# Patent

## Title
Glass fiber forming compositions

## Abstract

Mathematical relationship for ingredients for fiber glass compositions are used to identify properties of the glass. In particular the forming temperature and delta T. In one embodiment, the mathematical relationship of the ingredients is of a generic quaternary SiO2, CaO, Al2O3 and MgO glass system. The relationship of SiO2, CaO, Al2O3 and MgO of interest include RO=CaO+MgO, SiO2/CaO, SiO2/RO, SiO2/Al2O3; Al2O3/CaO; SiO2+Al2O3; SiO2—RO and Al2O3/RO or RO/Al2O3 when other ingredients or components are added to the glass batch materials to alter the forming and/or liquidus temperatures of the glass, for example Na2O, Li2O, K2O and B2O3 the following mathematical relationships are of interest, (SiO2+Al2O3)/(R2O+RO+B2O3) where RO is as previously defined and R2O=Na2O+Li2O+K2O. Each of the compositional features of the glass identified above reflects the relative balance between the fluidity (i.e. viscosity) of the glass melt and its crystallization potential. Low boron or boron free fiber glass compositions having a low forming temperature, e.g. 1178 to 1240° C. and a delta T greater than 50° C. in order that the composition can be processed at a low temperature while reducing the possibility of devitrification of the molten glass in the bushing area during a glass fiber forming operation. Fiber glass compositions having low boron, e.g. less than 5.10 percent by weight has a low forming temperature, e.g. 1193 to 1240° C. and a delta T greater than 50° C.

## Background
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a divisional of U.S. patent application Ser. No. 10/164,468, filed Jun. 6, 2002 now U.S. Pat. No. 6,962,886, which claims benefit of U.S. Provisional Application Nos. 60/330,178, filed Oct. 18, 2001; 60/230,474, filed Sep. 6, 2000 and 60/136,538, filed May 28, 1999. U.S. patent application Ser. No. 10/363,609 is a 35 USC 371 of PCT application Serial No. PCT/US01/27451, filed Sep. 5, 2001 (now U.S. Pat. No. 6,818,575), which claims benefit of U.S. Provisional Application No. 60/230,474, filed Sep. 6, 2000, and which is a continuation in part of U.S. patent application Ser. No. 09/980,248, filed Nov. 28, 2001 (now U.S. Pat. No. 6,686,304 B1), which is a 35 USC 371 of PCT application Ser. No. PCT/US00/14155, filed May 23, 2000, and claims benefit of U.S. Provisional Application 60/136,538, filed May 28, 1999.


BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to glass compositions, and more particularly to (1) fiber glass compositions, and (2) mathematical relationships of the ingredients of the glass compositions to identify thermal properties of the glass compositions e.g., forming and liquidus temperatures with an acceptable temperature difference to prevent devitrification of the molten glass during forming of glass fibers.
2. Discussion of the Technology
In the art of forming glass fibers it is recognized that the difference between the forming temperature and liquidus temperature is maintained at a value to prevent devitrification of the molten glass during fiber forming. For example, the most common glass composition for making continuous glass fiber strands for textiles and glass fiber reinforcements is known in the trade as “E glass”. The requirements as to what type of composition constitutes an E-glass composition are included in ASTM D578-00. An advantage of using E-glass having 6–10 percent by weight B2O3 is that its liquidus temperature is well below its forming temperature, i.e. typically greater than 56° C. (100° F.) and usually in the range of 83 to 111° C. (150 to 200° F.). As used herein, the terms “forming temperature”, “TFORM”, “log 3 forming temperature” and “log 3 FT” mean the temperature of the glass at which the viscosity of the glass is log 3, or 1000 poise, and the terms “liquidus temperature”, “liquidus T” and “TLIQ” mean the temperature at which the solid phase (crystals) and liquid phase (melt) of the glass are in equilibrium. The difference between TFORM and TLIQ, referred to herein as “delta T” or “ΔT”, is a common measure of the crystallization potential of a given melt composition. The lower the ΔT, in other words the smaller the difference between the forming temperature and the liquidus temperature, the greater the crystallization potential. In the glass fiber forming industry, ΔT is typically maintained at a temperature of at least 50° C. (90° F.) in order to prevent devitrification of the molten glass during a glass fiber forming operation, in particular, in the bushing area.
It is appreciated by those skilled in the art of forming glass fibers, that it is desirable to operate the glass fiber forming operation at low temperatures because operating the glass fiber forming operation at high temperatures results in high-energy usage, along with associated high-energy costs. In addition, the high temperatures accelerate degradation of the refractories used in the glass melting furnace, as well as the bushings used to form the fibers. The bushings include precious metals that cannot be recovered from the glass as the bushings wear.
It is recognized that boron and fluorine in addition to contributing to the electrical properties of the E-glass, e.g. dissipation factor and dielectric constant, also lower the forming and liquidus temperatures of the glass while providing a ΔT of at least 50° C. (90° F.). The boron in the form of an oxide and fluorine in the form of a fluoride are included in the glass batch materials and act as fluxes during the glass melting operation. E-glass can include up to 10 wt % B2O3 and up to 1.0 wt % fluoride (see ASTM D 578-00 §4.2). Although the boron effectively lowers the forming and liquidus temperatures while providing an acceptable ΔT value and the fluoride or fluorine acts as a flux, there are drawbacks. More particularly, these materials volatilize during melting and move with the exhaust gases into the exhaust system. If the boron and fluorine in the exhaust gases are not removed they are released to the atmosphere. Since boron and fluorine are considered pollutants, these emissions are closely controlled by environmental regulations, which in turn require careful control of the furnace operations and/or the use of costly additional pollution control equipment. In response to these concerns, the boron and/or fluorine content in E-glasses were reduced. For example, U.S. Pat. Nos. 4,542,106 and 5,789,329 and WO 99/12858 disclose boron free or low boron e.g. 1.8 wt % glasses having a forming temperature in the range of about 1258 to 1263° C. As can be appreciated by those skilled in the art of glass making, reducing or removing the boron and/or fluorine content in the batch materials raises the forming temperature. More particularly, the silica content increases as the boron content decreases, resulting in an increase in the forming temperature. As mentioned above, increasing the forming temperature results in high-energy usage, high-energy costs, and acceleration of the degradation of furnace refractories and bushings used to form the fibers.
For additional information concerning glass compositions and methods for fiberizing the glass composition, see K. Loewenstein, The Manufacturing Technology of Continuous Glass Fibres, (3d Ed. 1993) at pages 30–44, 47–60, 115–122 and 126–135, and F. T. Wallenberger (editor), Advanced Inorganic Fibers: Processes, Structures, Properties, Applications, (1999) at pages 81–102 and 129–168, which documents are hereby incorporated by reference.
In general, glass compositions having particular properties, e.g. forming temperature and delta T are identified by weight percent and/or molar percent of the components or ingredients in the glass. As can be appreciated by those skilled in the art of glass making and/or glass fiber forming, it would be advantageous to identify the performance of the glass compositions not only by the amount of a particular ingredient in the glass but also by a relationship, e.g. a mathematical relationship of the ingredients in the glass. WO 01/32576A1 discloses fiber glass compositions and the mathematical relationship of several of the ingredients, e.g. the combined Wt % of CaO and MgO, and the ratio of Al2O3/CaO, in the glass. Using the combination of glass ingredients, e.g. the absolute weight percent of silica with the relationship of other ingredients in the glass, e.g. the ratio of silica to RO (combined Wt % of CaO and MgO) would provide information regarding the melt properties of the glass.
SUMMARY OF THE INVENTION
The present invention provides a low boron containing or a boron free glass fiber forming composition that has a forming temperature of no greater than 1240° C. (2262° F.), a ΔT of at least 50° C. (90° F.), and one or more or all of the following compositional features:
a ratio of SiO2 to RO (i.e. CaO+MgO) in the range of 1.9 to 2.55;
a ratio of SiO2 to CaO in the range of 2.1 to 2.8;
a ratio of SiO2 to Al2O3 in the range of 3.7 to 5.0;
a ratio of Al2O3 to CaO in the range of 0.5 to 0.6;
a sum of SiO2 and Al2O3 in the range of 66.0 to 73.7 wt %;
a ratio of (SiO2+Al2O3) to (R2O+RO+B2O3) in the range of 2.0 to 3.0;
a ratio of Al2O3 to RO in the range of 0.4 to 0.6; and
a difference between SiO2 and RO; in the range of 26.5 to 36.6 wt %.
In one nonlimiting embodiment of the present invention, the glass composition further has a SiO2 content of greater than 57 weight percent and B2O3 of no greater than 2 weight percent. In another nonlimiting embodiment of the invention, the SiO2+Al2O3 content of the glass composition is less than 70 weight percent. In still another nonlimiting embodiment of the invention, the glass composition contains at least 1 weight percent TiO2.
In the discussion under Description of the Preferred Embodiments are glass compositions and mathematical relationship of different types of glasses. One such glass composition has the following ingredients:
















SiO2
55.70 to 59 percent by weight;



Al2O3
12.35 to 13.94 percent by weight;



CaO
24.40 to 24.80 percent by weight;



MgO
2.55 to 2.80 percent by weight;



TiO2
0.05 to 0.55 percent by weight;



Na2O
0.40 to 0.50 percent by weight;



K2O
0.40 to 0.60 percent by weight;



Na2O + K2O
0.85 to 1.50 percent by weight;



Fe2O3
0.20 to 0.40 percent by weight, and



B2O3
1.25 to 1.55 percent by weight, and










the following relationship of ingredients

















RO
26.25 to 27.60 wt %



SiO2/CaO
2.20 to 2.40



SiO2/RO
2.00 to 2.20



SiO2/Al2O3
3.95 to 4.70



Al2O3/CaO
0.50 to 0.60



SiO2 + Al2O3
69.00 to 70.50 wt %



SiO2 − RO
28.00 to 31.00 wt %



Al2O3/RO
0.45 to 0.55



R2O + RO + B2O3
28.90 to 30.00 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.25 to 2.45 and










a log 3 forming temperature in the range of 1210 to 1225° C. and ΔT is in the range of 52 to 65° C. R2O is equal to the wt % of k2O and Na2O.

Reference should be made to the Description of the Preferred Embodiments thereto for a more detailed summary of the glass compositions of the invention and the relationship of the ingredients of the glass compositions.
The glass compositions meeting the mathematical relationships of the instant invention provide a glass having a forming temperature of less than 1240° C., preferably 1205 to 1220° C., and more preferably between 1211 to 1218° C. for boron free glass and more preferably between 1187 to 1205° C. for boron containing glasses.


DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following discussion, all numbers expressing dimensions, physical characteristics, and so forth, used in the specification and claims are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical values set forth in the following specification and claims can vary depending upon the desired properties obtained by the practice of the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Moreover, all ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein. For example, a stated range of 1 wt % to 10 wt % should be considered to include any and all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more and ending with a maximum value of 10 or less, e.g., 5.5 to 10.
It should be appreciated that, unless otherwise indicated, all numerical values discussed herein, such as but not limited to weight percent of materials or temperatures, are approximate and are subject to variations due to various factors well known to those skilled in the art such as, but not limited to, measurement standards, equipment and techniques. As a result, such values are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any recognized deviations and/or errors are discussed. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
In the following discussion and in the claims the limits of defining the range are included in the range. For example and not limiting to the discussion, “in the range of 1230 to 1240° C.” and “in the range of equal to and greater than 1230° C. and equal to and less than 1240° C.” define the same range. Further in the preceding discussion, in the following discussion and in the claims, the terms “weight percent”, “wt %” and “percent by weight” are used herein interchangeably.
In one embodiment of the present invention, the mathematical relationships of the ingredients of a generic quaternary glass system are disclosed. The quaternary system includes SiO2, CaO, Al2O3 and MgO. As can be appreciated by those skilled in the art of making glass, in particular making glass fibers, MgO if not added to the batch materials is found in the batch materials as a tramp material, e.g. MgO is found in clay at 0.3 to 0.5 percent by weight. In the practice of the invention, MgO is added to the batch material to attain a level in the glass greater than the tramp level. The relationship of SiO2, CaO, Al2O3 and MgO of interest include RO=CaO+MgO, SiO2/CaO, SiO2/RO, SiO2/Al2O3; Al203/CaO; SiO2+Al2O3; SiO2—RO and Al203/RO or RO/Al2O3. In the present invention when other ingredients or components are added to the glass batch materials to alter the forming and/or liquidus temperatures of the glass and/or are present in the glass, for example but not limiting to the invention Na2O, Li2O, K2O and B2O3 the following mathematical relationships are of interest, (SiO2+Al2O3)/(R2O+RO+B2O3) where RO is as previously defined and R2O=Na2O+Li2O+K2O. In Tables 1 through 22, the relationship (SiO2+Al2O3)/(R2O+RO+B2O3) is shown as (Si+Al)/(R2O+RO+B) to fit the formula into a reasonable column width. Each of the compositional features of the glass identified above reflects the relative balance between the fluidity (i.e. viscosity) of the glass melt and its crystallization potential, as will be discussed below in more detail. The physical melt properties of interest in the present discussion are the forming temperature and the liquidus temperature because embodiments of the present invention are to provide low boron or boron free glass compositions having a low forming temperature and a desired ΔT. In this manner, the glass can be processed, e.g. to form glass fibers at a low temperature while reducing the possibility of devitrification of the molten glass, e.g. in the bushing area. Without limiting the present invention, one embodiment of the invention includes a glass composition having a forming temperature of no greater than 1240° C. (2264° F.) and a ΔT of at least 50° C. (90° F.).
In the following discussion, the mathematical relationship is to the ingredients in the glass; however, the invention is not limited thereto and contemplates identifying and using the relationship of the ingredients to be added to the batch, e.g. mixing the batch prior to melting the batch to form the glass. Further, in the following discussion the mathematical relationship of the ingredients will be in wt % of the ingredients in the glass composition; however, the invention is not limited thereto and maybe the mole % or any measurement that identifies the amount of the ingredient in the batch materials and/or the glass composition.
In regards to the ingredients or constituents of the quaternary system presented above, it is known that pure silica is the highest melting glass former. A pure silica melt does not have a well defined melting point. At 2500° C. (4532° F.), it has a viscosity of greater than about log 4 (10,000) poise, and as it cools to room temperature, it gradually solidifies and forms a glass. Pure calcia, magnesia and alumina melts are known to have very low viscosities, e.g. in the range of 0.5–2.0 poise at their respective melting points. These materials do not solidify into a glass as the melt cools but rather crystallize instantly at their sharply defined melting point. In a typical quaternary SiO2—Al2O3—CaO—MgO glass composition with 55–60% SiO2 and 21–26% CaO, each oxide of the quaternary system contributes its unique characteristics toward its balance of melt properties.
Based on the material properties of the constituents of the quaternary system for a glass composition having these components, it can be inferred that as SiO2, which is the largest oxide component of the glass composition in terms of weight percent, is reduced in a given composition of this type, the melt viscosity and the resulting log 3 forming temperature drops. If CaO, which is the second largest component of the glass composition in terms of weight percent, or MgO is increased in such a composition, the effect of RO (CaO+MgO) on the glass properties will be twofold. More specifically, it will not only increase the fluidity of the resulting melt (i.e. decrease its viscosity and the forming temperature) but it will also increase the crystallizability of the resulting melt (i.e. increase its liquidus temperature), and therefore reduce the ΔT.
As a result, although not required, in one nonlimiting embodiment of the present invention, the glass compositions have (1) the lowest SiO2 content that will yield the lowest log 3 forming temperature, which in the present invention is below 1240° C., preferably below 1220° C. in combination with (2) the ratio of SiO2 to RO that yields the process-required ΔT, which in the present invention is at least 50° C. Based on the forgoing and although not required in the practice of the invention, in one nonlimiting embodiment of the present invention, the silica level is preferably no greater than 62 wt % SiO2, in order to promote a lower log 3 forming temperature. In other nonlimiting embodiments of the present invention, the glass compositions have no greater than 60 wt % SiO2 and no greater than 58 wt % SiO2.
In general, MgO is included in a glass fiber forming composition because it has been found that the heating and melting profile of a glass fiber composition, and in particular the liquidus temperature, can be controlled and in particular optimized by controlling the amount of MgO. More particularly, by regulating the amount of MgO, the liquidus temperature can be selected to provide a delta T of at least 50° C. In addition, it has been determined that a eutectic exists in a generic quaternary SiO2—Al2O3—CaO—MgO system at around 2.5–2.8 wt % MgO. For a discussion of the eutectic reference may be had to WO 00/73231 which document is hereby incorporated by reference.
The value of the SiO2/RO ratio can be manipulated by changing the amount of SiO2 and/or RO to produce a glass composition having a ΔT as close as possible to the minimum desire ΔT. A decrease in the value of SiO2/RO, which is indicative of a reduction in the wt % of SiO2 and/or an increase in the wt % of CaO and/or MgO, or any change or combination of changes in the wt % of the SiO2, CaO and/or MgO, will effect the melt viscosity and ΔT, and will increase the crystallization potential. Conversely, an increase in the value of SiO2/RO will effect the melt viscosity and ΔT, and will decrease the crystallization potential. It should be appreciated that if the value of SiO2/RO ratio drops too low, ΔT can drop to an unacceptable level. Although not required, in one nonlimiting embodiment of the present invention, SiO2/RO is no greater than 2.40. In other nonlimiting embodiments, SiO2/RO is no greater than 2.35, or no greater than 2.30, or no greater than 2.25, or no greater than 2.20. In still another nonlimiting embodiment of the invention, the value of SiO2/RO ranges from 1.9 to 2.55, e.g. from 2.1 to 2.55 for boron-free glasses and from 1.9 to 2.4 for boron containing glasses.
In addition to the SiO2 level and the SiO2/RO ratio, the following parameters also describe the compositional envelope level of a quaternary glass composition: the SiO2/CaO ratio, the SiO2/Al2O3 ratio, the Al2O3/CaO ratio, the sum of SiO2+Al2O3, the difference between SiO2—RO, and the Al2O3/RO ratio. The following parameters describe the compositional envelope level of a glass composition containing additional temperature modifying ingredients: the sum of R2O+RO+B2O3, where R2O=Na2O+K2O+Li2O and the (SiO2+Al2O3)/(R2O+RO+B2O3) ratio.
While the SiO2/RO ratio at a given silica level describes the compositional effect of RO on the crystallization potential and melt fluidity, the SiO2/CaO ratio shows only the effect of CaO on the crystallization potential. If the MgO and the SiO2 levels are kept constant in a comparison of various melts, a decrease in the value of SiO2/CaO will show an increase in crystallization potential due to the contribution of CaO and visa versa. The SiO2—RO difference serves as a similar indicator, i.e. a decrease in the difference or a smaller difference is typically indicative of a greater relative amount of RO and thus an increase in the crystallization potential. And conversely, an increase in the difference or a larger difference in SiO2—RO is indicative of a reduction in the crystallization potential. In one nonlimiting embodiment of the present invention, the SiO2/CaO ratio of the glass composition ranges from 2.1 to 2.8, e.g. from 2.3 to 2.8 for boron-free glasses and from 2.2 to 2.7 for boron containing glasses. In another nonlimiting embodiment of the present invention, the SiO2—RO difference of the glass composition ranges from 26.5 to 36.6 wt %, e.g. from 30.5 to 36.6 wt % for boron-free glasses and from 26.5 to 34.0 wt % for boron containing glasses.
The sum of SiO2+Al2O3 is another parameter that describes the compositional envelope of a given melt. Up to about an Al2O3 level of 14 to 15 wt %, Al2O3 is believed to be able to participate in the network formation with SiO2, and counteract the crystallization potential of RO that is always present. At higher Al2O3 levels, e.g. greater than 15 wt %, Al2O3 will begin to act much like RO and contribute to a rise of the crystallization potential of a given melt. Thus a lower value of SiO2+Al2O3, which is indicative of a lower Al2O3 level for a glass composition of a given wt % of SiO2, will typically result in a lower crystallization potential, and a greater value of SiO2+Al2O3 will typically result in a higher crystallization potential for a given melt. In one nonlimiting embodiment of the present invention, the SiO2+Al2O3 sum of the glass composition ranges from 66.0 to 73.7 wt %, e.g. from 70.8 to 73.7 wt % for boron-free glasses and from 66.0 to 72.1 wt % for boron containing glasses.
Similarly with respect to SiO2/Al2O3 and based on the characteristics of the melt provided by the amount of Al2O3, an increasing ratio value would be indicative of a reduction in the amount of Al2O3 and/or an increase in the amount of SiO2 and would be accompanied by a reduction in the crystallization potential of the melt. Conversely, a decreasing ratio value would be accompanied by an increase in the crystallization potential of the melt. In one nonlimiting embodiment of the present invention, the SiO2/Al2O3 ratio of the glass composition ranges from 3.7 to 5.0, e.g. from 4.2 to 5.0 for boron-free glasses and from 3.7 to 4.9 for boron containing glasses.
As mentioned above, other mathematical relationships of ingredients of glass compositions, e.g. the Al2O3/CaO ratio, the Al2O3/RO ratio, and the (SiO2+Al2O3)/(R2O+RO+B2O3) ratio may be developed to characterize a given melt. In one nonlimiting embodiment of the present invention, the value of the Al2O3/CaO ratio of the glass composition ranges from 0.5 to 0.6. In another nonlimiting embodiment of the present invention, the value of the Al2O3/RO ratio of the glass composition ranges from 0.4 to 0.6, e.g. from 0.46 to 0.53 for boron-free glasses and from 0.46 to 0.56 for boron containing glasses. In still another nonlimiting embodiment of the present invention, the value of the (SiO2+Al2O3)/(R2O+RO+B2O3) ratio of the glass composition ranges from 2.0 to 3.0, e.g. from 2.3 to 3.0 for boron-free glasses and from 2.0 to 2.7 for boron containing glasses. Reference may be had to WO 01/32576 for additional discussion on the Al2O3/CaO ratio, and the (SiO2+Al2O3)/(R2O+RO+B2O3) ratio.
The discussion will now be directed to additives to the batch materials to alter the forming temperature, the liquidus temperature and the delta T. As previously discussed, boron is a material that is added to glass fiber compositions to reduce the forming temperature and the liquidus temperature. However, as discussed earlier, the inclusion of boron oxide results in the production of particulate emissions that, depending on the particulate level, may have to be removed from a melting furnace exhaust stream before being released into the environment. Although the amount of B2O3 can be as high as 10 wt % in an E-glass composition, in the present invention, the glass composition has no boron or a low boron content, i.e. has a B2O3 content in the range of 0 to 5.10 wt %. In other nonlimiting embodiments of the present invention, the glass fiber composition has no greater than 4 wt %, or no greater than 3 wt %, or no greater than 2 wt % B2O3. In another nonlimiting embodiment of the present invention, the glass composition is boron-free or essentially boron-free. As the term “essentially free” is used herein, the glass composition does not include an ingredient purposely added to the glass but found in the glass in trace amounts. In the practice of the invention, a glass having up to 0.05 wt % B2O3 is considered a boron free glass.
Further, as previously discussed, fluorine is a material added to glass fiber compositions as a flux, however, because of the environmental concerns it is preferred not to include fluorine. Nevertheless because equipment is available to remove the fluorine from the exhaust gases, the invention may be practiced using fluorine. In one nonlimiting embodiment of the present invention, the glass composition has low fluorine content, in other words, a fluorine content no greater than 0.30 wt %. In another nonlimiting embodiment, the glass composition is essentially fluorine free, i.e. it includes no more than a trace amount of fluorine, which is considered herein to be up to 0.05 wt %. In still another nonlimiting embodiment, the glass composition does not include any fluorine. Except where otherwise indicated, the glass fiber forming compositions disclosed and discussed herein are essentially fluorine free and/or do not include any fluorine.
Additional materials that can be added to the glass fiber composition to modify the melt properties, e.g. to reduce forming temperature and/or liquidus temperature of the glass include without limiting the glass compositions disclosed herein, are Li2O, Na2O, ZnO, TiO2, MnO and/or MnO2. Alkali oxides are network terminators and tend to effect the melt properties. K2O an alkali oxide is found in levels up to 0.60 wt % in commercial clays and is not normally added as a separate ingredient to the batch materials; however, in the practice of the invention it may be added as a separate material. In the practice of the invention alkali oxides up to 2.00 wt %, preferably 1 wt % are present in the glass of one embodiment of the invention. In the instance where K2O is present in the clay, the difference is usually made up by additions of Na2O and Li2O. Li2O is more effective in reducing the melt properties than Na2O. In one non-limiting embodiment of the present invention, the glass composition includes 0 to 1.0 wt % Li2O and/or 0 to 1.00 wt % Na2O and/or 0 to 1 wt % K2O. Non-alkali oxide ingredients usually employed to reduce the melt properties are ZnO, TiO2, MnO and/or MnO2 in amounts of about 0 to 1.5 wt % ZnO, 0 to 1.5 wt % TiO2, 0 to 3 wt % MnO and/or 0 to 3 wt % MnO2. It is believed that levels of these materials less than 0.05 wt % would be considered either tramp amounts or so low that they will not materially impact the glass melt properties. As a result, in another non-limiting embodiment, 0.05 to 1.5 wt % Li2O and/or 0.05 to 1.0 wt % Na2O and/or 0.05 to 1.0 wt % K2O and/or 0.05 to 1.5 wt % ZnO and/or 0.05 to 1.5 wt % TiO2 and/or 0.05 to 3 wt % MnO and/or 0.05 to 3 wt % MnO2 are included in the glass composition. In still another nonlimiting embodiment of the invention, the glass composition includes 0.2 to 1 wt % Li2O and/or 0.30 to 1.0 wt % Na2O and/or 0.30 to 1.0 wt % K2O and/or 0.2 to 1 wt % ZnO and/or 0.05 to 1.1 wt % TiO2 and/or up to 1 wt % MnO and/or up to 1 wt % MnO2.
As mentioned above, the ratio (SiO2+Al2O3)/(R2O+RO+B2O3) takes into account the wt % of the additions of B2O3, Na2O, K2O and Li2O that is (are) measured in the glass or batch materials regardless of the amount. Tramp amounts of these materials in the glass and/or batch are to be used to determine the value of the ratio. If any or all of the additions of B2O3, Na2O, K2O and Li2O are not determined to be present in the glass and/or batch, the value of zero is used for that ingredient in determining the value of the ratio. For example but not limiting to the invention, if Na2O, K2O and Li2O are present and B2O3 is not, the ratio (SiO2+Al2O3)/(R2$$ O+RO+B2O3) becomes (SiO2+Al2O3)/(R2O+RO). If none of the ingredients B2O3, Na2O, K2O and Li2O are determined to be present, the ratio becomes (SiO2+Al2O3)/RO. In the claims when the ratio (SiO2+Al2O3)/(R2O+RO+B2O3) is recited in a claim, if the ingredient is not recited in the claim, it is not used to determine the value of the ratio even though it is determined to be present in a glass covered by the claim. The preceding discussion is applicable to the other mathematical relationships, e.g. but not limiting thereto (R2O+RO+B2O3).
It should be appreciated that glass fiber compositions can include other oxides that are present as tramp materials such as BaO, ZrO2, SrO and Cr2O3, which are usually present in amounts of up to 0.1 wt %.
Further, it should be appreciated that the glass compositions disclosed herein can also include small amounts of other materials, for example melting and refining aids, tramp materials or impurities. For example and without limiting the present invention, melting and fining aids, such as FeO, Fe2O3 and SO3, are useful during production of the glass, but their residual amounts in the glass can vary and typically have minimal, if any, material effect on the properties of the glass product. In addition, small amounts of the additives discussed above can enter the glass composition as tramp materials or impurities included in the raw materials of the main constituents, e.g. 0 to 0.5 wt % for SO3, FeO and Fe2O3.
Shown in Table 1 are several examples of glass compositions of an embodiment of the invention, which relates to the use of clay having high K2O and low TiO2 levels in glass batch materials and to glass compositions having high levels K20 and low levels of TiO2. K2O and TiO2 can be added to the batch materials but are not economically removed from the clays used as batch material. As can be appreciated by those skilled in the art of glass melting and as discussed above, high K2O levels, e.g. up to 0.70 wt % in the glass raises the forming temperature by as much as about 7 to 10° C. in relation to a glass made from clay that introduces 0.10 wt % K2O. One embodiment of the present invention relates to an improved E-type glass having low weight percent B2O3, a forming temperature no greater than 1230° C., preferably no greater than 1222° C. and a delta T of at least 50° C. and preferably up to 65° C. The following are the main constituents in wt % based on the total weight percent of the final glass composition. The K2O and TiO2 listed in the ranges below for commercial glasses may or may not be added to the batch as separate ingredient. If the K2O and TiO2 are not added, it is expected that they would be present in the clay in varying wt % depending on the geographical location of the clay. Although the K2O and TiO2 would be present in the clay, the invention contemplates separate additions of K2O and/or TiO2 to be within the ranges listed below.
In those instances when the clay has high wt % of K2O, e.g. 0.60 wt %, it is necessary to counteract the effect of the K2O. More particularly, the K2O increases the forming temperature; therefore, the ingredients in the batch materials have to be modified so as to maintain a low forming temperature, e.g. below 1240° C. In one embodiment of the invention such a glass is as follows.

















most preferred



broad range
preferred range
range



















SiO2 (wt %)
52 to 60
54 to 59
55 to 58


Al2O3 (wt %)
8 to 16
11 to 14
12 to 14


CaO (wt %)
21 to 26
22 to 25
23 to 25


MgO (wt %)
1 to 5
1 to 4
2 to 3


K2O (wt %)
up to 1.00
0.30 to 1.00
0.30 to 0.80


Na2O (wt %)
up to 1.00
0.30 to 1.00
0.30 to 0.90


K2O + Na2O (wt %)
0.70 to 2.00
0.80 to 1.5
0.90 to 1.20


B2O3 (wt %)
1.00 to 3.50
1.10 to 2.00
1.20 to 1.50


Fe2O3 (wt %)
0.10 to 0.50
0.15 to 0.45
0.20 to 0.40


TiO2
up to 2.0
Up to 1.5
Up to 1.3









The range provided for B2O3 is not limiting to the invention, and it is recommended the level of boron be adjusted to meet local environmental regulations. As such, the invention may be practiced having levels of B2O3 up to 3.5 wt %.
The glasses of the invention are further defined by one or more of the following relationships:














broad range
preferred range



















wt % of CaO and
26 to 28 wt %
26 to 27.70 wt %



MgO (“RO”)


SiO2/CaO
2.10 to 2.80
2.20 to 2.70


SiO2/RO
1.90 to 2.55
1.90 to 2.40


SiO2/Al2O3
3.70 to 5.00
3.7 to 4.90


Al2O3/CaO
0.45 to 0.65
0.50 to 0.60


SiO2 + Al2O3
66 to 73.70 wt %
66 to 72.10 wt %


SiO2 − RO
26.56 to 36.60 wt %
26.50 to 34 wt %


Al2O3/RO
0.40 to 0.60
0.46 to 0.56


R2O + RO + B2O3
28.00 to 32.00 wt %
28.00 to 31.00 wt %


(SiO2 + Al2O3)/
2.00 to 3.00
2.00 to 2.70


(R2O + RO + B2O3)








where R2O is equal to the sum of Na2O + K2O.









Table 1 contains experimental samples A–E and illustrative samples F and G of glass compositions incorporating features of the invention. The ranges for the glass compositions listed on Table 1 are the minimum and maximum values for the glass compositions recited on Table 1, and for examples A–E, and F and G. More particularly, Table 1 provides the following glass compositions. A glass composition having the following ingredients:
















SiO2
55.00 to 58 percent by weight;



Al2O3
12.00 to 14.00 percent by weight;



CaO
23.80 to 24.80 percent by weight;



MgO
2.50 to 3.00 percent by weight;



TiO2
up to 0.60 percent by weight;



Na2O
0.40 to 0.50 percent by weight;



K2O
0.40 to 0.60 percent by weight;



Na2O2 + K2O
0.85 to 1.50 percent by weight;



Fe2O3
0.20 to 0.40 percent by weight;



B2O3
1.25 to 1.55 percent by weight;










the following relationship of ingredients
















RO
26.25 to 27.60 wt %



SiO2/CaO
2.20 to 2.40



SiO2/RO
2.00 to 2.20



SiO2/Al2O3
3.95 to 4.70



Al2O3/CaO
0.50 to 0.60



SiO2 + Al2O3
69.00 to 70.50 wt %



SiO2 − RO
28.00 to 31.00 wt %



Al2O3/RO
0.45 to 0.55



R2O + RO + B2O3
28.90 to 30.00 wt %



(SiO2 + Al2O3)/
2.25 to 2.45



(R2O + RO + B2O3)










    
    
        where R2O is equal to the sum of Na2O+K2O has a log 3 forming temperature in the range of 1210 to 1225° C. and ΔT is in the range of 52 to 65° C.
    
    


Another glass composition defined by Examples A–E of Table 1 has the following ingredients
















SiO2
55.60 to 57.60 percent by weight;



Al2O3
12.35 to 13.94 percent by weight;



CaO
24.40 to 24.80 percent by weight;



MgO
2.55 to 2.80 percent by weight;



TiO2
0.55 percent by weight;



Na2O
0.45 percent by weight;



K2O
0.45 to 0.58 percent by weight;



Na2O + K2O
0.90 to 1.03 percent by weight;



Fe2O3
0.25 to 0.38 percent by weight;



B2O3
1.30 to 1.50 percent by weight, and










the following relationships:
















RO
26.95 to 27.56 wt %



SiO2/CaO
2.25 to 2.29



SiO2/RO
2.02 to 2.14



SiO2/Al2O3
4.00 to 4.66



Al2O3/CaO
0.51 to 0.56



SiO2 + Al2O3
69.18 to 69.95 wt %



SiO2 − RO
28.04 to 30.65 wt %



Al2O3/RO
0.46 to 0.51



R2O + RO + B2O3
29.15 to 29.89 wt %



(SiO2 + Al2O3)/
2.31 to 2.40



(R2O + RO + B2O3)










    
    
        where R2O is equal to the sum of Na2O+K2O. The glass composition has a log 3 forming temperature in the range of 1156 to 1164° C. and ΔT is in the range of 54 to 65° C.
    
    


Other glass compositions identified by Examples F and G of Table 1 have the following ingredients

















SiO2
56.70 to 57.85 percent by weight;




Al2O3
12.55 to 13.67 percent by weight;



CaO
23.87 to 24.45 percent by weight;



MgO
2.55 to 2.62 percent by weight;



TiO2
0.05 to 0.34 percent by weight;



Na2O
0.44 to 0.455 percent by weight;



K2O
0.45 to 0.51 percent by weight;



Na2O + K2O
0.90 to 1.03 percent by weight;



Fe2O3
0.30 to 0.40 percent by weight;



B2O3
1.30 to 1.50 percent by weight, and










the following relationships:
















RO
26.49 to 27.00 wt %



SiO2/CaO
2.37 to 2.38



SiO2/RO
2.10 to 2.14



SiO2/Al2O3
4.15 to 4.61



Al2O3/CaO
0.51 to 0.57



SiO2 + Al2O3
70.37 to 70.44 wt %



SiO2 − RO
30.21 to 30.85 wt %



Al2O3/RO
0.46 to 0.52



R2O + RO + B2O3
28.94 to 29.20 wt %



(SiO2 + Al2O3)/
2.41 to 2.43



(R2O + RO + B2O3)










where R2O is equal to the sum of Na2O+K2O. The glasses have a log 3 forming temperature in the range of 1218 to 1219° C. and ΔT is in the range of 52 to 58° C.
The experimental or laboratory examples or samples on Table 1 discussed above and on Tables 2 to 19 to be discussed below, unless indicated otherwise, were prepared from certified or reagent grade oxides (e.g., pure silica or calcia). Examples F and G on Table 1 and examples H and I on Table 2 are illustrative examples and were not prepared in the following manner. The batch size for each example was 1000 grams. The individual batch ingredients were weighed out, combined and placed in a tightly sealed glass jar or plastic container. The sealed jar or container was then placed in a paint shaker for 15 minutes or in a tubular mixer for 25 minutes to effectively mix the ingredients. A portion of the batch was then placed into a platinum crucible, filling no more than 3⁄4 of its volume. The crucible was then placed in a furnace and heated at 1427° C. (2600° F.) for 15 minutes. The remaining batch was then added to the hot crucible and heated at 1427° C. (2600° F.) for 15 to 30 minutes. The furnace temperature was then raised to 1482° C. (2700° F.) and held there for 2 hours. The molten glass was then fritted in water and dried. The fritted samples were reheated to a temperature of 1482° C. (2700° F.) and held at that temperature for 2 hours. The molten glass was then fritted again in water and dried.
The forming temperature, i.e. the glass temperature at a viscosity of 1000 poise, was determined by ASTM method C965-81, and the liquidus temperature by ASTM method C829-81. The log 3 forming temperature of the compositions reported in Tables 1–20 were determined by a comparison of the glass against physical standards supplied by the National Institute of Standards and Testing (NIST). In the Tables, the majority of the reported log 3 forming temperatures is based on comparison to NIST 710A. Several of the reported log 3 forming temperatures are originally based on NIST 717A which uses a borosilicate standard; in those instances the values were converted to correspond to NIST 710A. Therefore all the log 3 forming temperatures are considered to based on NIST 710A.
Selected samples had ingredients added that would be found in the clays used in the batch material. Such as K2O, TiO2, calcium fluoride, SrO and/or Cr2O3.
The weight percent of the constituents of the compositions shown in Tables 1–19 except for Examples F to I are based on the weight percent of each constituent in the batch. It is believed that the batch weight percent is generally about the same as the weight percent of the melted sample, except for glass batch materials that volatilize during melting, e.g. boron, fluorine and moisture absorbing materials. In the case of boron, it is believed that the weight percent of B2O3 in a laboratory sample will be 10 to 16 weight percent less than the weight percent of B2O3 in the batch composition, the precise loss depending on the composition and melting conditions. In the case of fluorine, it is believed that the weight percent of fluorine in a laboratory test sample will be about 50 percent less than the weight percent of fluorine in the batch composition, the precise loss depending on the composition and melting conditions. In the case of CaO, CaO has an certified ignition loss 3–5 wt % (an average of 4 wt %). The determination of the wt % of the batch materials for the samples listed on Tables 1–19 except for Examples F to I, through an oversight, did not take into account the ignition loss. Therefore in practicing the invention, this fact should be taken into account. Because the 4 wt % error is minimal, the recitation of the wt % of CaO recited in the claims covering the embodiments of the glass compositions listed on Tables 1–19 does not take into account the ignition loss. Table 20 has production samples; the analysis of the ingredients of the examples on Table 20 were measured using XRF analysis.
As can be appreciated by those skilled in the art of converting data from laboratory melt sample to data used to prepare batch materials for commercial glass production, the melting and fining conditions of the commercial furnace to be used to melt and fine the glass has to be taken into consideration. It is believed that glass fiber compositions made from commercial grade materials and melted under conventional operating conditions will have similar batch and melt weight percents as discussed above, with the precise loss depending, in part, on the furnace operating temperature, through-put and quality of commercial batch materials. The amount of boron and fluorine reported in the tables takes into consideration the expected loss of these materials and represents the expected amount of the material in the glass composition. It should further be appreciated that the glass compositions disclosed herein can also include small amounts of other materials, for example melting and refining aids, tramp materials or impurities. For example and without limiting the present invention, melting and fining aids, such as SO3, are useful during production of the glass, but their residual amounts in the glass can vary and have no material effect on the properties of the glass product. In addition, small amounts of the additives discussed above can enter the glass composition as tramp materials or impurities included in the raw materials of the main constituents.
With reference to Tables 1–20, in each column of each Table, the upper portion of the column lists the wt % of the ingredients in the glass composition based on the batch materials as was discussed above. The middle portion of the column lists the mathematical relationship of the ingredients discussed above for the particular glass composition in the same column to obtain the thermal properties listed in the bottom portion of the column e.g. forming temperature, liquidus temperature and delta T (except for certain compositions of Table 20 which is discussed below). Table 20 lists production glasses. The amount of each constituent of the commercial compositions shown in the Table 20 is the weight percent in the glass. The weight percent for the B2O3 was determined using Neutron Transmission analysis techniques and the weight percent for the remaining constituents was determined using X-ray fluorescence analysis (also referred to as “XRF analysis”), all of which are well known to those skilled in the art.
Tables 2 through 19 include, but are not limited to glass compositions disclosed in U.S. patent application Ser. No. 09/980,248, filed Nov. 28, 2001, in the name of Frederick T. Wallenberger for “Glass Fiber Compositions” (hereinafter “U.S. patent application Ser. No. 09/980,248”); in PCT International Application No. PCT/US01/27451, filed Sep. 5, 2001, in the name of Frederick T. Wallenberger for “Glass Fiber Forming Compositions” (hereinafter “USPCT No. 01/27451”); and in International Application No. PCT/US00/14155. U.S. patent application Ser. No. 09/980,248 and International Application No. PCT/US00/14155 are jointly referred to as “U.S. patent application Ser. No. 09/980,248 Combined”.
U.S. patent application Ser. No. 09/980,248 Combined and USPCT No. 01/27451 discloses base composition for the low boron glass fibers that are suitable for textiles and glass fiber reinforcements, that may be used in the practice of the present invention. In general, the base compositions of U.S. patent application Ser. No. 09/980,248 Combined and USPCT No. 01/27451 include the following main constituents in weight percent ranges based on the total weight of the final glass composition with the exception that USPCT No. 01/27451 glass compositions are boron free.















broad range
preferred range
most preferred range



















SiO2 (wt %)
52 to 62
52 to 61
53 to 59


Na2O (wt %)
0 to 2
up to 1.5
up to 1


CaO (wt %)
16 to 25
20 to 25
22 to 24


Al2O3 (wt %)
8 to 16
11 to 14
12 to 14


Fe2O3 (wt %)
0.05 to 0.80
up to 0.5
up to 0.4


K2O (wt %)
0 to 2
Up to 1
up to 0.1


B2O3 (wt %)
1 to 5
1 to 3.5
1 to 2.5









In one embodiment the glass comparison of U.S. patent application Ser. No. 09/980,248 Combined, the glass composition can include on or more of the following materials in the following amounts.














broad range
preferred range




















Li2O (wt %)
0.05 to 1.5
0.2 to 1



ZnO (wt %)
0.05 to 1.5
0.2 to 1



MnO (wt %)
0.05 to 3
up to 1



MnO2 (wt %)
0.05 to 3
up to 1










For a complete discussion of the glass compositions disclosed in U.S. patent application Ser. No. 09/980,248 Combined, and disclosed in USPCT No. 01/27451, reference should be made thereto.

As discussed above the examples of Table 1 incorporate features of one embodiment of the invention, a low boron glass composition (see the upper portion of the columns on Table 1) having a forming temperature below 1240° C., more preferably below 1225° C. and a delta T of greater than 50° C. (see the lower portion of the columns on Table 1). The examples of Tables 1–20 include another feature of the invention, mathematical relationship of the ingredients in the glass composition (see middle portion of the columns on Tables 1–20) to provide a forming temperature below 1240° C. and a delta T of greater than 50° C. (see the lower portion of the columns on Tables 1–20). The mathematical relationship of the ingredients of the glass compositions on Table 1 were discussed above. Tables 2–19 include, but are not limited to examples of glass compositions disclosed in U.S. patent application Ser. No. 09/980,248 Combined and/or in USPCT No. 01/27451. Additional examples within the scope of the inventions of U.S. patent application Ser. No. 09/980,248 Combined and/or in USPCT No. 01/27451 are included herein. For example, but not a complete relationship, examples 188–236 are selected from U.S. patent application Ser. No. 09/980,248 Combined and examples 7–24, 43–50,78–185, and 219–267 are selected from USPCT No. 01/27451. Examples A–E, 25, 30–32, 60–75 are examples, among others, presented by this application. The examples identified as selected from U.S. patent application Ser. No. 09/980,248 Combined and/or in USPCT No. 01/27451 and those added to the Tables by the instant disclosure are not complete. For a complete comparison reference may be had to U.S. patent application Ser. No. 09/980,248 Combined and/or in USPCT No. 01/27451.
For a better appreciation of the invention the samples on Tables 2–19 are categorized according to the following types of glass compositions.

    Type-1 Glasses boron-free (Table 2)
    Type-2 Glasses up to about 5.10 wt % B2O3 (Tables 3–11)
    Type-3 Glasses boron-free with lithium oxide (Tables 12 and 13)
    Type-4 Glasses boron-free with lithium and zinc oxide (Tables 14 and 15)
    Type-5 Glasses boron-free with zinc oxide (Table 16)
    Type-6 Glasses up to 5 wt % B2O3 with lithium oxide (Tables 17 and 18)
    Type-7 Glasses miscellaneous glass (Table 19)

Table 20, as previously discussed includes production glasses.



Table 2 (Type 1 Glasses) includes glass compositions of a quaternary system that includes SiO2 in the range of 57–60 wt %, preferably in the range of 57.25–59.50 wt % and more preferable in the range of 57.40–59.10; Al2O3 in the range of 12–14 wt %, preferably in the range of 12–13.50 wt % and more preferably in the range of 12.15–13.45 wt %; CaO in the range of 23–25 wt %, preferable in the range of 23.50–24.50 wt % and more preferable in the range of 23.70–24.20 wt %, and MgO in the range of 2–3 wt %, preferably in the range of 2.25–2.75 wt % and more preferably in the range of 2.50–2.60 wt %. The glass compositions of Table 2 further include TiO2 in the range of up to 1.25 wt %, preferably in the range of 0.25–1.20 wt % and more preferably in the range of 0.50–1.15 wt %; Na2O in the range of 0.75–1.25, preferably in the range of 0.75–1.00 wt % and more preferably in the range of 0.85–0.95 wt %; and Fe2O3 in the range of up to 0.50 wt %, preferably 0.10–0.50 wt % and more preferably in the range of 0.30–0.40 wt %. The compositions of Table 2 are boron free. Compositions 1–6 of Table 2 further include TiO2 in the range of 1.00–1.25 wt %, preferably in the range of 1.00–1.20 wt % and more preferably in the range of 1.05–1.15 wt %; Na2O in the range of 0.75–1.25, preferably in the range of 0.75–1.00 wt % and more preferably in the range of 0.85–0.95 wt %; and Fe2O3 in the range of up to 0.35 wt %, preferably 0.10–0.30 wt % and more preferably in the range of 0.20–0.30 wt %. Compositions H and I include TiO2 in the range of 0–0.9 wt %, preferably in the range of 0.25–0.75 wt % and more preferably in the range of 0,50–0.6 wt %; Na2O in the range of 0.75–1.25, preferably in the range of 0.75–1.00 wt % and more preferably in the range of 0.85–0.95 wt %; and Fe2O3 in the range of up to 0.50 wt %, preferably 0.10–0.40 wt % and more preferably in the range of 0.30–0.40 wt %.
A glass composition having the ingredients of Table 2 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1240° C. and a delta T of greater than 50° C., e.g.:















Relationship
Broad Range
Preferred Range









RO (CaO + MgO)
26 to 28 wt %
26.00 to 27.25 wt %



SiO2/CaO
2.10 to 2.80
2.30 to 2.80



SiO2/RO
1.90 to 2.55
1.90 to 2.40



SiO2/Al2O3
3.70 to 5.00;
4.20 to 5.00



Al2O3/CaO
0.40 to 0.75
0.50 to 0.60



SiO2 + Al2O3
66 to 73.7 wt %
70.80 to 73.7 wt %



R2O + RO
27 to 28.15 wt
27.15 to 20 wt %



(SiO2 + Al2O3)/
2.0 to 3.0
2.30 to 3.00



(R2O + RO)



SiO2 − RO
26.5 to 36.6 wt %
30.50 to 36.60 wt %



Al2O3/RO
0.4 to 0.6
0.46 to 0.56










The Type 1 glass compositions are not expected to have any Li2O or K2O, therefore R2O is equal to the wt % of Na2O.
As can be appreciated, Table 2 also provides ranges for the ingredients and the relationships. For example, but not limiting to the invention, the ranges for the ingredients of the glass compositions listed on Table 2 are as follows:
















SiO2
57.45 to 59.05 percent by weight;



Al2O3
12.20 to 13.40 percent by weight;



CaO
23.75 to 24.35 percent by weight;



MgO
2.55 percent by weight;



TiO2
1.10 percent by weight;



Na2O3
0.90 percent by weight, and



Fe2O3
0.25 percent by weight.










The range of the mathematical relationships of the ingredients from Table 2 for the glass compositions listed on Table 2 is found in Table 21 in the column entitled “Type 1 Glasses”. The glasses on Table 2 have a log 3 forming temperature in the range of 1232 to 1240° C. and a ΔT in the range of 58 to 74° C.
Table 2 also provides ranges for the Examples 1–6. More particularly, from Table 2 Example 1–6 glass compositions have the following ingredients and ranges:
















SiO2
57.45 to 59.05 percent by weight;



Al2O3
12.20 to 13.68 percent by weight;



CaO
23.75 to 24.50 percent by weight;



MgO
2.55 to 2.58 percent by weight;



TiO2
0.55 to 1.10 percent by weight;



Na2O3
0.90 to 0.91 percent by weight, and



Fe2O3
0.25 to 0.35 percent by weight.










The range of the mathematical relationship of the ingredients from Table 2 for the glass compositions of Examples 1–6 can be found on Table 21 under Type 1 Glasses. The glass compositions of Examples 1–6 have a log 3 forming temperature in the range of 1232 to 1240° C. and a ΔT in the range of 58 to 74° C.
Further, Table 2 provides ranges for the Examples H and I. More particularly, from Table 2 Examples H and I glass compositions have the following ingredients and ranges:
















SiO2
57.60 to 58.18 percent by weight;



Al2O3
13.55 to 13.68 percent by weight;



CaO
23.75 to 24.50 percent by weight;



MgO
2.55 to 2.58 percent by weight;



TiO2
0.55 percent by weight;



Na2O3
0.90 to 0.91 percent by weight, and



Fe2O3
0.35 percent by weight.










the ranges for the mathematical relationships of the ingredients from Table 2 are as follows:

















RO
26.33 to 27.05 wt %



SiO2/CaO
2.35 to 2.45



SiO2/RO
2.13 to 2.20



SiO2/Al2O3
4.25



Al2O3/CaO
0.55 to 0.58



SiO2 + Al2O3
71.15 to 71.86 wt %



SiO2 − RO
30.55 to 31.85 wt %



Al2O3/RO
0.50 to 0.52



R2O + RO
27.24 to 27.95 wt %



(SiO2 + Al2O3)/
2.55 to 2.64



(R2O + RO)










The glass compositions of Examples H and I have a log 3 forming temperature in the range of 1238 to 1240° C. and a ΔT of 55° C.
Tables 3–11 (Type 2 Glasses) include glass compositions of a quaternary system that includes SiO2 in the range of 50–60 wt %, preferably in the range of 52.25–59.00 wt % and more preferable in the range of 52.90–58.00 wt %; Al2O3 in the range of 10–14 wt %, preferably in the range of 11–14 wt % and more preferably in the range of 12–14 wt %; CaO in the range of 21–26 wt %, preferable in the range of 21.50–25.50 wt % and more preferable in the range of 22–25 wt %, and MgO in the range of 1–4 wt %, preferably in the range of 1.25–3.50 wt % and more preferably in the range of 1.45–3.25 wt %. The compositions of Tables 3–11 include B2O3 in an amount within the range of greater than 0 to 5.10 wt %, e.g. 0.90–5.10 wt %. The compositions of Table 3–11 further contemplate TiO2 in the range of 0.25–1.25 wt %, more likely in the range of 0.40–1.20 wt % and most likely in the range of 0.45–1.15 wt %; Na2O in the range of 0.25–1.25, preferably in the range of 0.35–1.00 wt % and more preferably in the range of 0.40–0.95 wt %; K2O expected in amounts up to 0.60 wt %; and Fe2O3 in the range of up to 0.50 wt %, preferably up to −0.45 wt % and more preferably up to 0.40 wt %. Other ingredients included in the glass compositions of Tables 3–11 but not limited thereto are fluorine in amounts up to 0.50 wt %; SrO in amounts up to 0.15 wt % and Cr2O3 in amounts up to 0.15 wt %.
A glass composition having ingredients of Tables 3–11 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1240° C. and a delta T of greater than 50° C.:















Relationship
Broad Range
Preferred Range









RO (CaO + MgO)
24 to 29 wt %
24.75 to 27.60 wt %



SiO2/CaO
2.10 to 2.80
2.15 to 2.75



SiO2/RO
1.95 to 2.55
1.90 to 2.40



SiO2/Al2O3
3.70 to 5.00
3.70 to 4.90



Al2O3/CaO
0.45 to 0.65
0.45 to 0.65



SiO2 + Al2O3
66 to 73.7 wt %
66 to 72.1 wt %



R2O + RO + B2O3
27.5 to 34 wt %
28 to 33 wt %



(SiO2 + Al2O3)/
2.00 to 3.00
2.00 to 2.70



(R2O + RO + B2O3)



SiO2 − RO
26.5 to 36.6 wt %
26.5 to 34 wt %



Al2O3/RO
0.40 to 0.60
0.46 to 0.56










Type 2 glasses of Tables 3–11 do not consider Li2O as an ingredient; therefore for Tables 3–11, R2O is equal to the sum of the wt % of K2O and Na2O. If one of the ingredients is not present in the glass it is given a 0 wt %. For the glasses listed on each of the Tables 3, 4, 6, 7, 10 and 11, only the addition of Na2O is considered; therefore for the glasses on the individual Tables 3, 4, 6, 7, 10 and 11, R2O is equal to the wt % of Na2O. For the glasses listed on the individual Tables 5, 8 and 9, Na2O and K2O are considered; therefore for the glasses on the individual Tables 5, 8 and 9, R2O is equal to the sum of the wt % of Na2O and K2O.
As can be appreciated, each of the Tables 3–11 provides ranges for the ingredients and the relationships. For example and not limiting to the invention, Tables 3–11 provide glass compositions having the following ingredients in the following ranges:
















SiO2
53.00 to 57.75 percent by weight;



Al2O3
12.20 to 14 percent by weight;



CaO
22.25 to 24.95 percent by weight;



MgO
1.50 to 3.00 percent by weight;



TiO2
0.50 to 1.10 percent by weight;



Na2O
0.45 to 0.90 percent by weight;



K2O
0 to 0.38 percent by weight;



Fe2O3
0 to 0.30 percent by weight;



B2O3
1.30 to 5.02 percent by weight;



F
0 to 0.50 percent by weight;



SrO
0 to 0.13 percent by weight, and



Cr2O3
0 to 0.13 percent by weight.










The mathematical relationship of the ingredients is found on Table 21 in the column entitled “Type 2 Glasses”.
Table 3 provides glass compositions having ingredients in the following ranges:
















SiO2
56.00 to 56.65 percent by weight;



Al2O3
13.05 to 13.60 percent by weight;



CaO
23.50 to 24.25 percent by weight;



MgO
2.50 to 2.55 percent by weight;



TiO2
0.50 to 1.10 percent by weight;



Na2O
0.90 percent by weight;



Fe2O3
0.25 percent by weight, and



B2O3
2.00 percent by weight.










The ranges for the mathematical relationships of ingredients of the glass compositions on Table 3 from Table 3 are as follows:
















RO
26.05 to 26.75 wt %



SiO2/CaO
2.31 to 2.41



SiO2/RO
2.09 to 2.17



SiO2/Al2O3
4.12 to 4.28



Al2O3/CaO
0.56 to 0.57



SiO2 + Al2O3
69.60 to 69.95 wt %



SiO2 − RO
29.25 to 30.60 wt %



Al2O3/RO
0.50 to 0.52



R2O + RO + B2O3
28.95 to 29.65 wt %



(SiO2 + Al2O3)/
2.35 to 2.41



(R2O + RO + B2O3)










The glass compositions of Table 3 have a log 3 forming temperature in the range of 1200 to 1220° C. and a ΔT is in the range of 56 to 69° C.
Table 4 provides glass compositions having Ingredients in the following ranges:
















SiO2 is
56.25 to 57.75 percent by weight;



Al2O3 is
12.20 to 13.20 percent by weight;



CaO
23.75 to 24.25 percent by weight;



MgO
2.55 percent by weight;



TiO2
1.10 percent by weight;



Na2O
0.90 percent by weight;



Fe2O3
0.25 percent by weight, and



B2O3
1.30 to 1.40 percent by weight.










The ranges for the mathematical relationships of the ingredients for the glass compositions of Table 4 from Table 4 are as follows:
















RO
26.30 to 26.80 wt %



SiO2/CaO
2.32 to 2.43



SiO2/RO
2.10 to 2.20



SiO2/Al2O3
4.26 to 4.73



Al2O3/CaO
0.51 to 0.56



SiO2 + Al2O3
69.45 to 69.95 wt %



SiO2 − RO
29.45 to 31.45 wt %



Al2O3/RO
0.46 to 0.50



R2O + RO + B2O3
28.50 to 29.00 wt %



(SiO2 + Al2O3)/
2.39 to 2.45.



(R2O + RO + B2O3)










The glass compositions of Table 4 have a log 3 forming temperature in the range of 1200 to 1218° C. and a ΔT in the range of 55° C. to 70° C.
The glass compositions of Table 5 have the following ingredients in the following ranges:
















SiO2
55.19 to 56.00 percent by weight;



Al2O3
13.10 to 13.80 percent by weight;



CaO
24.50 to 24.67 percent by weight;



MgO
2.55 to 2.95 percent by weight;



TiO2
1.10 percent by weight;



Na2O
0.45 percent by weight;



K2O
0.45 to 0.58 percent by weight;



Fe2O3
0.25 to 0.38 percent by weight, and



B2O3
1.30 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 5 from Table 5 are as follows:
















RO
27.08 to 27.45 wt %



SiO2/CaO
2.25 to 2.28



SiO2/RO
2.01 to 2.07



SiO2/Al2O3
4.01 to 4.19



Al2O3/CaO
0.53 to 0.56



SiO2 + Al2O3
68.75 to 69.37 wt %



SiO2 − RO
27.78 to 28.92 wt %



Al2O3/RO
0.48 to 0.51



R2O + RO + B2O3
29.28 to 29.74 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.31 to 2.37










The glass compositions of Table 5 have a log 3 forming temperature in the range of 1210 to 1222° C. and a ΔT in the range of 53 to 79° C.
Table 6 provides glass compositions having ingredients in the following ranges:
















SiO2
56.15 to 57.60 percent by weight;



Al2O3
13.25 to 13.95 percent by weight;



CaO
24.40 to 24.95 percent by weight;



MgO
2.55 percent by weight;



TiO2
0.55 percent by weight;



Na2O
0.90 percent by weight;



Fe2O3
0.25 to 0.35 percent by weight, and



B2O3
1.30 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 6 from Table 6 are as follows:
















RO
26.95 to 27.50 wt %



SiO2/CaO
2.25 to 2.36



SiO2/RO
2.04 to 2.14



SiO2/Al2O3
4.01 to 4.66



Al2O3/CaO
0.54 to 0.57



SiO2 + Al2O3
69.50 to 69.99 wt %



SiO2 − RO
28.65 to 30.65 wt %



Al2O3/RO
0.46 to 0.51



R2O + RO + B2O3
29.15 to 29.70 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.34 to 2.40.










The glass compositions of Table 6 have a log 3 forming temperature in the range of 1211 to 1220° C. and a ΔT is in the range of 52 to 66° C.
Table 7 provides glass compositions having ingredients in the following ranges:
















SiO2
55.25 to 56.15 percent by weight;



Al2O3
13.05 to 13.30 percent by weight;



CaO
23.00 to 24.20 percent by weight;



MgO
2.55 percent by weight;



TiO2
0.25 to 1.25 percent by weight;



Na2O
0.90 percent by weight;



Fe2O3
0.25 percent by weight; and



B2O3
3.00 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 7 from Table 7 are as follows:
















RO
25.55 to 26.75 wt %



SiO2/CaO
2.28 to 2.44



SiO2/RO
2.07 to 2.20



SiO2/Al2O3
4.15 to 4.30



Al2O3/CaO
0.55 to 0.56



SiO2 + Al2O3
68.20 to 69.20 wt %



SiO2 − RO
28.45 to 30.60 wt %



Al2O3/RO
0.50 to 0.51



R2O + RO + B2O3
29.45 to 30.65 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.24 to 2.35










The glass compositions of Table 7 have a log 3 forming temperature in the range of 1193 to 1212° C. and a ΔT is in the range of 64 to 90° C.
Table 8 provides glass compositions having ingredients in the following ranges:
















SiO2
54.12 to 55.25 percent by weight;



Al2O3
13.20 to 13.40 percent by weight;



CaO
24.20 to 24.55 percent by weight;



MgO
2.55 percent by weight;



TiO2
0.55 percent by weight;



Na2O
0.45 to 0.50 percent by weight;



K2O
0.45 to 0.55 percent by weight;



Fe2O3
0.25 to 0.28 percent by weight;



B2O3
3.00 percent by weight;



F
up to 0.20 percent by weight, and



SrO
up to 0.12 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 8 from Table 8 are as follows:
















RO
26.75 to 27.55 wt %



SiO2/CaO
2.20 to 2.28



SiO2/RO
1.96 to 2.07



SiO2/Al2O3
4.06 to 4.15



Al2O3/CaO
0.54 to 0.55



SiO2 + Al2O3
67.55 to 68.55 wt %



SiO2 − RO
26.57 to 28.30 wt %



Al2O3/RO
0.49 to 0.50



R2O + RO + B2O3
30.65 to 31.40 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.14 to 2.22










The glass compositions of Table 8 have a log 3 forming temperature in the range of 1190 to 1204° C. and a ΔT is in the range of 55 to 83° C.
Table 9 provides glass compositions having Ingredients in the following ranges:
















SiO2
53.00 to 53.50 percent by weight;



Al2O3
13.10 to 14.00 percent by weight;



CaO
24.00 percent by weight;



MgO
1.25 to 2.50 percent by weight;



TiO2
0.50 percent by weight;



Na2O
0.90 percent by weight;



K2O
0.37 percent by weight;



Fe2O3
0.10 percent by weight;



B2O3
4.93 to 5.02 percent by weight;



F
0.50 percent by weight;



SrO
0.13 percent by weight, and



Cr2O3
0.13 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 9 from Table 9 are as follows:
















RO
25.50 to 26.50 wt %



SiO2/CaO
2.21 to 2.23



SiO2/RO
2.00 to 2.10



SiO2/Al2O3
3.82 to 4.05



Al2O3/CaO
0.55 to 0.58



SiO2 + Al2O3
66.10 to 67.50 wt %



SiO2 − RO
26.50 to 28.00 wt %



Al2O3/RO
0.49 to 0.55



R2O + RO + B2O3
31.70 to 32.79 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.02 to 2.13










The glass compositions of Table 9 have a log 3 forming temperature in the range of 1167 to 1177 and a ΔT is in the range of 57 to 69° C.
Table 10 provides glass compositions having ingredients in the following ranges:
















SiO2
55.40 to 57.75 percent by weight;



Al2O3
12.20 to 13.80 percent by weight;



CaO
22.25 to 24.85 percent by weight;



MgO
2.05 to 2.60 percent by weight;



TiO2
0.50 to 1.10 percent by weight;



Na2O
0.90 percent by weight;



Fe2O3
0.25 percent by weight, and



B2O3
1.00 to 3.00 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 10 from Table 10 are as follows:
















RO
26.80 to 27.35 wt %



SiO2/CaO
2.23 to 2.55



SiO2/RO
2.05 to 2.27



SiO2/Al2O3
4.04 to 4.69



Al2O3/CaO
0.51 to 0.59



SiO2 + Al2O3
69.00 to 70.95 wt %



SiO2 − RO
28.05 to 32.55 wt %



Al2O3/RO
0.46 to 0.53



R2O + RO + B2O3
28.15 to 30.25 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.28 to 2.67










The glass compositions of Table 10 have a log 3 forming temperature in the range of 1202 to 1240° C. and a ΔT is in the range of 53 to 100° C.
The glass compositions listed on Table 10 and the glasses within the scope of the embodiment of Table 10 have a forming temperature in the range of 1202 to 1240° C. It should be noted that the measured delta T for Example 91 was 34° C.; it is believed that this is a measuring error the liquidus temperature because the glass composition of Example 90 has similar ingredients, a lower liquidus temperature and a delta T of 100° C. Therefore the delta T of Example 91 is considered to be about 90° C. The preferred glass compositions from Table 10 are those that provide the forming temperature range 1202 to 1219° C. and a delta T greater than 5° C., more particularly Examples 78–91.
The glass compositions of Examples 78–91 of Table 10 from Table 10 have the following ingredients in the following ranges:
















SiO2
55.40 to 56.65 percent by weight;



Al2O3
13.05 to 13.80 percent by weight;



CaO
23.00 to 24.85 percent by weight;



MgO
2.50 to 2.55 percent by weight;



TiO2
0.50 to 1.10 percent by weight;



Na2O
0.90 percent by weight;



Fe2O3
0.25 percent by weight, and



B2O3
2.00 to 3.00 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Examples 78–91 of Table 10 from Table are as follows:
















RO
25.55 to 27.35 wt %



SiO2/CaO
2.23 to 2.44



SiO2/RO
2.03 to 2.20



SiO2/Al2O3
4.06 to 4.34



Al2O3/CaO
0.54 to 0.57



SiO2 + Al2O3
68.95 to 69.95 wt %



SiO2 − RO
28.05 to 30.60 wt %



Al2O3/RO
0.49 to 0.53



R2O + RO + B2O3
28.95 to 30.25 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.28 to 2.41










The glass composition of Examples 78–91 have a log 3 forming temperature in the range of 1202 to 1219° C. and a ΔT is in the range of 53 to 100° C.
The glass compositions of Table 11 from Table 11 have the following ingredients in the following ranges:
















SiO2
56.10 to 57.75 percent by weight;



Al2O3
12.20 to 13.38 percent by weight;



CaO
23.75 to 24.42 percent by weight;



MgO
2.55 percent by weight;



TiO2
0.55 to 1.10 percent by weight;



Na2O
0.90 percent by weight;



Fe2O3
0.25 percent by weight; and



B2O3
1.30 to 1.40 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 11 from Table 11 are as follows:
















RO
26.30 to 26.97 wt %



SiO2/CaO
2.30 to 2.43



SiO2/RO
2.08 to 2.20



SiO2/Al2O3
4.19 to 4.73



Al2O3/CaO
0.51 to 0.54



SiO2 + Al2O3
69.48 to 69.95 wt %



SiO2 − RO
29.13 to 31.45 wt %



Al2O3/RO
0.46 to 0.50



R2O + RO + B2O3
28.60 to 29.17 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.38 to 2.44










The glass compositions of Table 11 have a log 3 forming temperature in the range of 1215 to 1218° C. and a ΔT in the range of 63° C. to 65° C.
Tables 12 and 13 (Type 3 Glasses) include glass compositions of a quaternary system that includes SiO2 in the range of 55–62 wt %, preferably in the range of 56–61 wt % and more preferably in the range of 57.5–61 wt %; Al2O3 in the range of 10–14 wt %, preferably in the range of 11–14 wt % and more preferably in the range of 11.75–13.75 wt %; CaO in the range of 20–26 wt %, preferable in the range of 21.50–25.00 wt % and more preferable in the range of 21.75–24.50 wt %, and MgO in the range of 1–4 wt %, preferably in the range of 1.35–3.50 wt % and more preferably in the range of 1.60–3.25 wt %. The compositions of Tables 12 and 13 are boron free. The compositions of Tables 12 and 13 contemplate a TiO2 in the range of 0.25–1.75 wt %, more likely in the range of 0.40–1.60 wt % and most likely more preferably in the range of 0.45–1.55 wt %; Na2O in amounts up to 0.75 wt %, preferably in amounts up to 0.70 wt % and more preferably in amounts up to 0.65 wt %; Li2O in amounts in the range of 0.10 to 1.25 wt %, preferably in the range of 0.20 to 1.10 wt %, and more preferably in the range of 0.30 to 1.00 wt %, and Fe2O3 in the range of up to 0.50 wt %, preferably up to 0.45 wt % and more preferably up to 0.30 wt %.
A glass composition having ingredients of Tables 12 and 13 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1240° C. and a delta T of greater than 50° C.:












Relationship
Broad Range
Preferred Range







RO (CaO + MgO)
23.50 to 27.50 wt %
23.75 to 27.00 wt %


SiO2/CaO
2.10 to 2.80
2.30 to 2.80


SiO2/RO
1.90 to 2.55
2.10 to 2.55


SiO2/Al2O3
3.70 to 5.00
4.20 to 5.00


Al2O3/CaO
0.45 to 0.65
0.45 to 0.60


SiO2 + Al2O3
66 to 73.7 wt %
70.8 to 73.7 wt %


R2O + RO
24.75 to 28 wt %
25 to 27.75 wt %


(SiO2 + Al2O3)/(R2O + RO)
2.00 to 3.00
2.30 to 3.00


SiO2 − RO
26.5 to 36.6 wt %
30.50 to 36.6 wt %


Al2O3/RO
0.40 to 0.60
0.46 to 0.53









The Type 3 Glasses do not consider the addition of K2O; therefore for Type 3 Glasses R2O is equal to the sum of the wt % of Na2O and Li2O.
As can be appreciated, each of the Tables 12 and 13 provides ranges for the ingredients and the relationships. More particularly, the glass compositions of Tables 12 and 13 from Tables 12 and 13 have the following ingredients in the following ranges:
















SiO2
57.65 to 60.75 percent by weight;



Al2O3
12.00 to 13.64 percent by weight;



CaO
22 to 24.155 percent by weight;



MgO
1.70 to 3.40 percent by weight;



TiO2
0.50 to 1.50 percent by weight;



Na2O
0.30 to 0.60 percent by weight;



Li2O
0.30 to 1.00 percent by weight, and



Fe2O3
up to 0.25 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Tables 12 and 13 from Tables 12 and 13 are on Table 21 under the column entitled “Type 3 Glasses”. The glass compositions of Tables 12 and 13 have a log 3 forming temperature in the range of 1205 to 1240° C., and a ΔT in the range of 50 to 100° C.
The glass compositions of Table 12 from Table 12 have the following ingredients in the following ranges:
















SiO2
58.25 to 59.97 percent by weight;



Al2O3
12.19 to 13.64 percent by weight;



CaO
22.04 to 23.65 percent by weight;



MgO
2.50 to 3.12 percent by weight;



TiO2
0.50 to 1.50 percent by weight;



Na2O
up to 0.30 percent by weight;



Li2O
0.90 to 0.91 percent by weight, and



Fe2O3
0.20 to 0.25 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 12 are as follows:
















RO
24.94 to 26.20 wt %



SiO2/CaO
2.47 to 2.72



SiO2/RO
2.23 to 2.40



SiO2/Al2O3
4.31 to 4.92



Al2O3/CaO
0.55 to 0.59



SiO2 + Al2O3
71.55 to 73.03 wt %



SiO2 − RO
32.15 to 34.91 wt %



Al2O3/RO
0.48 to 0.52



R2O + RO
25.84 to 27.10 wt %



(SiO2 + Al2O3)/(R2O + RO)
2.64 to 2.79










The glass compositions of Table 12 have a log 3 forming temperature in the range of 1211° C. and to 1218° C., and a ΔT in the range of 56 to 68° C.
The glass compositions of Table 13 from Table 13 have the following ingredients in the following ranges:
















SiO2
57.65 to 60.75 percent by weight;



Al2O3
12.00 to 13.40 percent by weight;



CaO
22.00 to 24.15 percent by weight;



MgO
1.70 to 3.12 percent by weight;



TiO2
0.50 to 1.50 percent by weight;



Na2O
0.45 to 0.90 percent by weight;



Li2O
0.45 to 1.00 percent by weight, and



Fe2O3
up to 0.25 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 13 from Table 13 is as follows:
















RO
24.25 to 26.70 wt %



SiO2/CaO
2.39 to 2.72



SiO2/RO
2.16 to 2.51



SiO2/Al2O3
4.30 to 4.92



Al2O3/CaO
0.50 to 0.59



SiO2 + Al2O3
71.05 to 73.67 wt %



SiO2 − RO
31.35 to 36.56 wt %



Al2O3/RO
0.47 to 0.55



R2O + RO
24.91 to 27.90 wt %



(SiO2 + Al2O3)/(R2O + RO)
2.30 to 2.96










The glass compositions have a log 3 forming temperature in the range of 1205 to 1240° C. and a ΔT are in the range of 50 to 101° C.
The glass compositions listed on Table 13 and the glasses within the scope of the embodiment of Table 13 have a forming temperature in the range of 1205 to 1240° C. and a delta T in the range of 50–100° C.; however the preferred glass compositions from Table 13 are those that provide the forming temperature range of 1205 to 1220° C. and more preferably in the range of 1205–1218° C. more particularly Examples 123, 124, 125, 127–132, 147, 153, 155, 157, 160 and 161 with the appropriate delta T, e.g. 50° C. or greater.
The glass compositions of Examples 123, 124, 125, 127–132, 147, 153, 155, 157, 160 and 161 from Table 13 have the following ingredients in the following ranges:
















SiO2
57.65 to 60.33 percent by weight;



Al2O3
12.22 to 13.40 percent by weight;



CaO
22.00 to 24.15 percent by weight;



MgO
2.30 to 3.40 percent by weight;



TiO2
0.50 to 1.50 percent by weight;



Na2O
up to 0.45 percent by weight;



Li2O
0.45 to 1.00 percent by weight, and



Fe2O3
up to 0.25 percent by weight.










The ranges for the mathematical relationships of the ingredients of Examples 123, 124, 125, 127–132, 147, 153, 155, 157, 160 and 161 from Table 13 are as follows:
















RO
24.84 to 26.70 wt %



SiO2/CaO
2.39 to 2.72



SiO2/RO
2.16 to 2.42



SiO2/Al2O3
4.30 to 4.92



Al2O3/CaO
0.52 to 0.59



SiO2 + Al2O3
71.05 to 72.80 wt %



SiO2 − RO
31.35 to 35.37 wt %



Al2O3/RO
0.47 to 0.52



R2O + RO
25.74 to 27.60 wt %



(SiO2 + Al2O3)/(R2O + RO)
2.30 to 2.81










The glass compositions have a log 3 forming temperature in the range of 1205 to 1220° C. and in the range of 1205 to 1218° C., and a ΔT in the range of equal to and greater than 50° C. and equal to and less than 60° C.
The selection of the above examples is made based on the low forming temperature. As can be appreciated, if a high delta T is of interest then Examples 135-141, for example, would be of interest because they have a delta T in the range of 77-100° C.
The glass compositions of Examples 135–141 from Table 13 have the following ingredients in the following ranges:
















SiO2
59.55 to 60.57 percent by weight;



Al2O3
12.25 to 13.10 percent by weight;



CaO
22.31 to 23.85 percent by weight;



MgO
1.70 to 3.10 percent by weight;



Na2O
up to 0.30 percent by weight



TiO2
1.10 percent by weight, and



Li2O
up to 0.60 percent by weight.










The ranges for the mathematical relationships of the ingredients of Examples 135–141 from Table 13 is as follows:
















RO
24.01 to 25.95 wt %



SiO2/CaO
2.50 to 2.71



SiO2/RO
2.29 to 2.52



SiO2/Al2O3
4.62 to 4.88



Al2O3/CaO
0.52 to 0.59



SiO2 + Al2O3
71.80 to 73.67 wt %



SiO2 − RO
33.60 to 36.56 wt %



Al2O3/RO
0.47 to 0.55



R2O + RO
24.91 to 26.85 wt %



(SiO2 + Al2O3)/(R2O + RO)
2.67 to 2.96










The glass compositions have a log 3 forming temperature in the range of 1234 to 1240° C., and a ΔT is in the range of 61 to 100° C.
Tables 14 and 15 (Type 4 Glasses) include glass compositions of a quaternary system that includes SiO2 in the range of 55–62 wt %, preferably in the range of 56–61 wt % and more preferable in the range of 57–60 wt %; Al2O3 in the range of 10–14 wt %, preferably in the range of 11–14 wt % and more preferably in the range of 12–13.75 wt %; CaO in the range of 21–26 wt %, preferable in the range of 21.50–25.00 wt % and more preferable in the range of 21.75–24.50 wt %, and MgO in the range of 1–3.25 wt %, preferably in the range of 1.50–3.00 wt % and more preferably in the range of 1.75–2.75 wt %. The compositions of Tables 14 and 15 are boron free. The compositions of Tables 14 and 15 contemplate TiO2 in the range of 0.25–1.75 wt %, more likely in the range of 0.40–1.50 wt % and most likely in the range of 0.45–1.25 wt %; Li2O in amounts in the range of 0.25 to 1.25 wt %, preferably in the range of 0.30 to 1.10 wt %, and more preferably in the range of 0.40 to 1.00 wt %, ZnO in amounts in the range of 0.25 to 1.25 wt %, preferably in the range of 0.30 to 1.15 wt %, and more preferably in the range of 0.40 to 1.10 wt %, and Fe2O3 in the range of up to 0.50 wt %, preferably up to 0.35 wt % and more preferably up to 0.30 wt %.
A glass composition having ingredients of Tables 14 and 15 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1240° C. and a delta T of greater than 50° C.:












Relationship
Broad Range
Preferred Range







RO (CaO + MgO)
24 to 28 wt %
25.25 to 27.00 wt %


SiO2/CaO
2.10 to 2.80
2.30 to 2.60


SiO2/RO
1.90 to 2.55
2.10 to 2.55


SiO2/Al2O3
3.70 to 5.00
4.20 to 5.00


Al2O3/CaO
0.45 to 0.65
0.50 to 0.60


SiO2 + Al2O3
68 to 73.7 wt %
70.8 to 72 wt %


R2O + RO
25 to 30 wt %
26.0 to 28 wt %


(SiO2 + Al2O3)/(R2O + RO)
2.00 to 3.00
2.30 to 3.00


SiO2 − RO
26.5 to 36.60 wt %
30.5 to 36.60 wt %


Al2O3/RO
0.40 to 0.60
0.46 to 0.53









The Type 4 Glasses are shown only to have Li2O; therefore for Type 4 Glasses R2O is equal to the wt % of Li2O.
As can be appreciated, each of the Tables 14 and 15 provides ranges for the ingredients and the relationships. More particularly, the glass compositions of Tables 14 and 15 from Tables 14 and 15 have the following ingredients in the following ranges:
















SiO2
57.35 to 59.618.30 percent by weight;



Al2O3
12.16 to 13.63 percent by weight;



CaO
22.85 to 24.22 percent by weight;



MgO
1.90 to 2.55 percent by weight;



TiO2
0.50 to 1.10 percent by weight;



Li2O
0.45 to 0.90 percent by weight;



ZnO
0.45 to 1.00 percent by weight, and



Fe2O3
up to 0.25 percent by weight.










in the range of 1195 to 1229° C., and a ΔT is in the range of 54 to 71° C. The ranges for the mathematical relationships of the ingredients of the glass compositions of Tables 14 and 15 are found on Table 21 under the column entitled “Type 4 Glasses”. The glass compositions have a log 3 forming temperature.

The glass compositions of Table 14 from Table 14 have the following ingredients in the following ranges:
















SiO2
58.00 to 58.30 percent by weight;



Al2O3
13.03 to 13.33 percent by weight;



CaO
22.85 to 23.84 percent by weight;



MgO
2.50 to 2.55 percent by weight;



TiO2
0.50 to 1.10 percent by weight;



Li2O
0.90 percent by weight;



ZnO
1.00 percent by weight, and



Fe2O3
up to 0.25 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 14 from Table 14 are as follows:
















RO
25.40 to 26.34 wt %



SiO2/CaO
2.43 to 2.54



SiO2/RO
2.20 to 2.29



SiO2/Al2O3
4.36 to 4.47



Al2O3/CaO
0.55 to 0.58



SiO2 + Al2O3
71.13 to 71.58 wt %



SiO2 − RO
31.66 to 32.75 wt %



Al2O3/RO
0.49 to 0.52



R2O + RO
26.30 to 27.24 wt %



(SiO2 + Al2O3)/(R2O + RO)
2.61 to 2.71










The glass compositions have a log 3 forming temperature in the range of 1204 to 1213° C., and a ΔT in the range of 56 to 71° C.
The glass compositions of Table 15 from Table 15 have the following ingredients in the following ranges:
















SiO2
57.35 to 59.61 percent by weight;



Al2O3
12.16 to 13.63 percent by weight;



CaO
23.14 to 24.22 percent by weight;



MgO
1.90 to 2.55 percent by weight;



TiO2
0.50 to 1.10 percent by weight;



Li2O
0.45 to 0.90 percent by weight;



ZnO
0.45 to 1.00 percent by weight, and



Fe2O3
up to 0.25 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 15 from Table 15 are as follows:
















RO
25.64 to 26.60 wt %



SiO2/CaO
2.41 to 2.54



SiO2/RO
2.18 to 2.29



SiO2/Al2O3
4.26 to 4.90



Al2O3/CaO
0.50 to 0.59



SiO2 + Al2O3
70.55 to 71.77 wt %



SiO2 − RO
31.15 to 33.61 wt %



Al2O3/RO
0.47 to 0.53



R2O + RO
26.45 to 27.50 wt %



(SiO2 + Al2O3)/(R2O + RO)
2.60 to 2.71










The glass compositions of Table 15 have a log 3 forming temperature in the range of 1195 to 1229° C., and a ΔT in the range of 54 to 59° C.
Table 16 (Type 5 Glasses) include glass compositions of a quaternary system that includes SiO2 in the range of 55–62 wt %, preferably in the range of 56–61 wt % and more preferable in the range of 58–60 wt %; Al2O3 in the range of 10–14 wt %, preferably in the range of 11.00–13.5 wt % and more preferably in the range of 11.75–13.25 wt %; CaO in the range of 21–25 wt %, preferable in the range of 21.25–24.00 wt % and more preferable in the range of 21.25–23.00 wt %, and MgO in the range of 1–4.00 wt %, preferably in the range of 1.25–3.50 wt % and more preferably in the range of 1.50–3.50 wt %. The compositions of Table 16 are boron free. The compositions of Table 16 contemplate TiO2 in the range of 0.50–2.00 wt %, more likely in the range of 0.50–1.50 wt % and more preferably in the range of 0.75–1.25 wt %; Na2O in amounts in no greater than 2.00 wt %; preferably no greater than 1.50 wt %, and more preferably no greater than 1.25 wt %; ZnO in amounts in the range of 0.50 to 3.00 wt %, preferably in the range of 0.50 to 2.75 wt %, and more preferably in the range of 0.75 to 2.50 wt %, and Fe2O3 in the range of up to 0.50 wt %, preferably in the range of up to 0.35 wt % and more preferably in the range of up to 0.30 wt %.
A glass composition having ingredients of Table 16 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1240° C. and a delta T of greater than 50° C.:












Relationship
Broad Range
Preferred Range







RO (CaO + MgO)
23 to 28 wt %
24.0 to 27.0 wt %


SiO2/CaO
2.10 to 2.80
2.30 to 2.80


SiO2/RO
1.90 to 2.55
2.10 to 2.55


SiO2/Al2O3
3.70 to 5.00
4.20 to 5.00


Al2O3/CaO
0.45 to 0.65
0.45 to 0.60


SiO2 + Al2O3
66 to 73.7 wt %
70.8 to 73.7 wt %


R2O + RO
25 to 28 wt %
26.0 to 27.0 wt %


(SiO2 + Al2O3)/(R2O + RO)
2.00 to 3.00
2.30 to 3.0


SiO2 − RO
30 to 39 wt %
31.50 to 37. wt %


Al2O3/RO
0.40 to 0.60
0.46 o 0.53









Type 5 Glasses were considered having Na2O; therefore R2O is equal to the sum of Na2O in wt %.
As can be appreciated, Table 16 provides ranges for the ingredients and the relationships. More particularly, the glass compositions of Table 16 from Table 16 have the following ingredients in the following ranges:
















SiO2
58.70 to 59.00 percent by weight;



Al2O3
11.90 to 12.00 percent by weight;



CaO
22.40 to 22.50 percent by weight;



MgO
3.40 percent by weight;



TiO2
1.00 percent by weight;



Na2O
0.90 percent by weight;



ZnO
1.00 to 1.50 percent by weight, and



Fe2O3
up to 0.20 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 16 from Table 16 are on Table 21 under the column entitled “Type 5 Glasses”. The glass compositions of Table 16 have a log 3 forming temperature in the range of 1231 to 1234° C., and a ΔT in the range of 50 to 59° C.
Tables 17 and 18 (Type 6 Glasses) include glass compositions of a quaternary system that includes SiO2 in the range of 50–62 wt %, preferably in the range of 52–61 wt % and more preferable in the range of 53.50–60.25 wt %; Al2O3 in the range of 10–14 wt %, preferably in the range of 11.00–14.00 wt % and more preferably in the range of 11.90–13.75 wt %; CaO in the range of 21–26 wt %, preferable in the range of 22.00–25.00 wt % and more preferable in the range of 22.50–24.25 wt %, and MgO in the range of 1–4.00 wt %, preferably in the range of 1.50–3.00 wt % and more preferably in the range of 2.25–2.75 wt %. The compositions of Tables 17 and 18 have B2O3 in the range of 0.50–5.00 wt %, preferably in the range of 0.50–4.00 and more preferably in the range of 0.75–3.25 wt %. The compositions of Tables 17 and 18 contemplate further include TiO2 in the range of 0.25–2.00 wt %, more likely in the range of 0.35–1.50 wt % and most likely in the range of 0.40–1.25 wt %; Na2O in amounts no greater than 1.00 wt %; preferably no greater than 0.90 wt %, and more preferably no greater than 0.75 wt %; K2O in amounts no greater than 0.50 wt %; preferably no greater than 0.35 wt %, and more preferably no greater than 0.20 wt %; Li2O in amounts in the range of 0.10 to 1.25 wt %, preferably in the range of 0.20 to 1.10 wt %, and more preferably in the range of 0.25 to 1.00 wt %, and Fe2O3 in the range of 0.10–0.50 wt %, preferably in the range of 0.15–0.50 wt % and more preferably in the range of 0.20–0.40 wt %.
A glass composition having ingredients of Tables 17 and 18 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1240° C. and a delta T of greater than 50° C.:















Relationship
Broad Range
Preferred Range









RO (CaO + MgO)
24 to 28 wt %
25.0 to 27.20 wt %



SiO2/CaO
2.10 to 2.80
2.20 to 2.70



SiO2/RO
1.90 to 2.55
1.90 to 2.40



SiO2/Al2O3
3.50 to 5.00
4.00 to 5.00



Al2O3/CaO
0.50 to 0.60
0.50 to 0.60



SiO2 + Al2O3
66 to 73.7 wt %
67 to 72.1 wt %



R2O + RO + B2O3
25 to 32 wt %
26.50 to 32 wt %



(SiO2 + Al2O3)/
2.00 to 3.25
2.30 to 3.00



(R2O + RO + B2O3)



SiO2 − RO
26.5 to 36.6 wt %
27 to 36.6 wt %



Al2O3/RO
0.40 to 0.60
0.46 to 0.56










Type 6 Glasses of Tables 17 and 18 included Li2O, K2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O, K2O and Na2O. Individual Table 17 includes Li2O and Na2O; therefore R2O for Table 17 is equal to the sum in wt % of Li2O and Na2O. Individual Table 18 includes Li2O, K2O and Na2O; therefore R2O for Table 18 is equal to the sum in wt % of Li2O, K2O and Na2O.
As can be appreciated, Tables 17 and 18 provide ranges for the ingredients and the relationships. More particularly, the glass compositions of Tables 17 and 18 have the following ingredients in the following ranges:
















SiO2
54.60 to 59.53 percent by weight;



Al2O3
12.16 to 13.63 percent by weight;



CaO
22.87 to 24.05 percent by weight;



MgO
2.00 to 2.55 percent by weight;



TiO2
0.49 to 1.10 percent by weight;



Na2O
0 to 0.60 percent by weight;



K2O
0 to 0.10 percent by weight;



Li2O
0.30 to 0.91 percent by weight;



Fe2O3
0.23 to 0.30 percent by weight, and



B2O3
0.90 to 3.00 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Tables 17 and 18 are on Table 21 under the column entitled “Type 6 Glasses”. The glass compositions of Table 17 and 18 have a log 3 forming temperature in the range of 1187 to 1239° C., and a ΔT in the range of 50 to 142° C.
The glass compositions of Table 17 have the following ingredients in the following ranges:
















SiO2
57.60 to 58.50 percent by weight;



Al2O3
12.76 to 13.43 percent by weight;



CaO
23.40 to 23.84 percent by weight;



MgO
2.50 percent by weight;



TiO2
0.50 percent by weight;



Na2O
up to 0.60 percent by weight;



Li2O
0.90 percent by weight;



Fe2O3
0.23 percent by weight, and



B2O3
1.00 to 1.20 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Tables 17 are as follows:
















RO
25.90 to 26.34 wt %



SiO2/CaO
2.42 to 2.48



SiO2/RO
2.19 to 2.24



SiO2/Al2O3
4.30 to 4.47



Al2O3/CaO
0.54 to 0.57



SiO2 + Al2O3
70.83 to 71.47 wt %



SiO2 − RO
31.26 to 32.39 wt %



Al2O3/RO
0.49 to 0.52



R2O + RO + B2O3
27.80 to 28.44 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.49 to 2.57










Type 6 Glasses of Table 17 included Li2O, K2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O, K2O and Na2O.
The glass compositions of Table 17 have a log 3 forming temperature in the range of 1192 to 1198° C., and a ΔT in the range of 55 to 63° C.
The glass compositions of Table 18 have the following ingredients in the following ranges:
















SiO2
54.60 to 59.53 percent by weight;



Al2O3
12.16 to 13.63 percent by weight;



CaO
22.93 to 24.05 percent by weight;



MgO
2.00 to 2.55 percent by weight;



TiO2
0.49 to 1.10 percent by weight;



Na2O
up to 0.60 percent by weight;



K2O
up to 0.10 percent by weight;



Li2O
0.30 to 0.91 percent by weight;



Fe2O3
0.23 to 0.35 percent by weight, and



B2O3
0.60 to 3.00 percent by weight.










The ranges for the mathematical relationships of the ingredients of the glass compositions of Tables 17 are as follows:
















RO
25.80 to 26.60 wt %



SiO2/CaO
2.22 to 2.66



SiO2/RO
2.01 to 2.39



SiO2/Al2O3
4.09 to 4.90



Al2O3/CaO
0.51 to 0.59



SiO2 + Al2O3
67.95 to 72.05 wt %



SiO2 − RO
27.50 to 33.84 wt %



Al2O3/RO
0.46 to 0.53



R2O + RO + B2O3
26.70 to 31.10 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.18 to 2.68










The glass compositions of Table 18 have a log 3 forming temperature in the range of 1187 to 1239° C., and a ΔT in the range of 50 to 42° C.
The glass compositions listed on Table 18 and the glasses within the scope of the embodiment of Table 18 have a forming temperature in the range of 1187 to 1239° C. and a delta T in the range of 50–142° C.; however the preferred glass compositions from Table 18 are those that provide the forming temperature range 1187 to 1220° C. (Examples 188–213, 215–229, 213–235, 238–240, 242–260 and 262–267) and more preferably in the range of 1187–1205° C. (Examples 188–191, 194, 195, 198, 200, 201, 202–205, 208, 209, 211–213, 215–219, 221–223, 225–229, 233–235, 239, 242, 257 and 260).
A glass composition having the ingredients in the ranges mentioned above for Table 18 and having the following relationships will provide glass compositions having a log 3 forming temperature in the range of 1187 to 1220° C., and a ΔT is in the range of 50 to 139° C.:
















RO
25.80 to 26.60 wt %



SiO2/CaO
2.22 to 2.66



SiO2/RO
2.01 to 2.39



SiO2/Al2O3
4.09 to 4.87



Al2O3/CaO
0.51 to 0.59



SiO2 + Al2O3 
67.95 to 72.05 wt %



SiO2 − RO
27.50 to 33.84 wt %



Al2O3/RO
0.46 to 0.53



R2O + RO + B2O3
26.70 to 31.10 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.18 to 2.68










The glass compositions from Table 18 having a log 3 forming temperature in the range of 1187 to 1205° C., and a ΔT in the range of 50 to 124° C. have the following ingredients and the following ranges:
















SiO2
57.60 to 59.21 percent by weight;



Al2O3
12.16 to 13.63 percent by weight;



CaO
22.87 to 24.06 percent by weight;



MgO
2.36 to 2.50 percent by weight;



TiO2
0.49 to 1.10 percent by weight;



Na2O
up to 0.30 percent by weight;



K2O
up to 0.09 percent by weight;



Li2O
0.70 to 0.90 percent by weight;



Fe2O3
0.23 to 0.29 percent by weight, and



B2O3
1.00 to 1.20 percent by weight;










And the following relationships:

















RO
25.23 to 26.54 wt %



SiO2/CaO
2.40 to 2.57



SiO2/RO
2.17 to 2.32



SiO2/Al2O3
4.26 to 4.87



Al2O3/CaO
0.52 to 0.59



SiO2 + Al2O3
70.63 to 71.73 wt %



SiO2 − RO
31.06 to 33.61 wt %



Al2O3/RO
0.47 to 0.53



R2O + RO + B2O3
27.23 to 28.64 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.47 to 2.63










The selection of these examples is made based on the low forming temperature. Further examples 266–268 are glass compositions that have a low forming temperature with 0.30 wt % Li2O. Examples 265–268 define a range of ingredients and relationship of the ingredients to provide a low Li2O containing glass with low forming temperature. As can be appreciated and as previously discussed, if a high delta T is of interest then Examples from Table 18 have a high delta T, e.g. above 75° C. may be selected to define glass compositions.
Table 19 (Type 7 Misc. Glasses) includes glass compositions of a quaternary system that includes SiO2 in the range of 56–60 wt %, preferably in the range of 57–59 wt % and more preferable in the range of 57.50–59 wt %; Al2O3 in the range of 10–14 wt %, preferably in the range of 11.00–14.00 wt % and more preferably in the range of 11.50–14.00 wt %; CaO in the range of 21–25 wt %, preferable in the range of 22.00–24.00 wt % and more preferable in the range of 22.50–24.00 wt %, and MgO in the range of 2.00–4.00 wt %, preferably in the range of 2.00–3.00 wt % and more preferably in the range of 2.25–2.75 wt %. The compositions of Table 19 include B2O3 in the range of 0–1.50 wt %, preferably in the range of 0–1.25 wt % and more preferably in the range of 0–1.10 wt %. The compositions of Table 19 contemplates further includes TiO2 in the range of 0.25–1.50 wt %, more likely preferably in the range of 0.25–1.35 wt % and most likely in the range of 0.40–1.25 wt %; Na2O in amounts no greater than 1.25 wt %; preferably no greater than 1.10 wt %, and more preferably no greater than 1.00 wt %; ZnO in amounts no greater than 0.50 wt %; preferably no greater than 0.40 wt %, and more preferably no greater than 0.35 wt %; MnO in amounts no greater than 4.00 wt %; preferably no greater than 3.50 wt %, and more preferably no greater than 3.25 wt %; MnO2 in amounts no greater than 4.00 wt %; preferably no greater than 3.50 wt %, and more preferably no greater than 3.25 wt %, and Fe2O3 in the range of 0.10–0.50 wt %, preferably in the range of 0.15–0.50 wt % and more preferably in the range of 0.20–0.40 wt %.
A glass composition having ingredients of Tables 19 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1240° C. and a delta T of greater than 50° C.:












Relationship
Broad Range
Preferred Range







RO (CaO + MgO)
24 to 27 wt %
25.00 to 26.50 wt %


SiO2/CaO
2.10 to 2.80
2.20 to 2.70


SiO2/RO
1.90 to 2.55
1.90 to 2.40


SiO2/Al2O3
3.70 to 5.00
3.70 to 4.90


Al2O3/CaO
0.45 to 0.65
0.55 to 0.60


SiO2 + Al2O3
66 to 73.7 wt %
66 to 72.1 wt %


R2O + RO + B2O3
25 to 28 wt %
25.75 to 27.50 wt %


(SiO2 + Al2O3)/
2.00 to 3.00
2.00 to 2.75


(R2O + RO + B2O3)


SiO2 − RO
26.50 to 36.6 wt %
26.5 to 34.00 wt %


Al2O3/RO
0.40 to 0.60
0.46 to 0.56









The Misc. Glasses included Li2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O and Na2O.

Table 19 provides the following ranges for the following ingredients:
















SiO2
57.72 to 58.70 percent by weight;



Al2O3
11.88 to 13.35 percent by weight;



CaO
22.80 to 23.50 percent by weight;



MgO
2.43 to 2.50 percent by weight;



TiO2
0.50 to 1.10 percent by weight;



Na2O3
0.87–0.90 percent by weight;



Li2O
0 to 0.30 percent by weight;



ZnO
0 to 0.30 percent by weight;



Fe2O3
0.22–0.25 percent by weight;



MnO
0.30 to 3.00 percent by weight;



MnO2
0 to 3.00 percent by weight, and



B2O3
0 to 1.00 percent by weight.










The relationships for the ingredients of the glass compositions on Table 19 are as follows:
















RO
25.23 to 26.00 wt %



SiO2/CaO
2.49 to 2.54



SiO2/RO
2.25 to 2.29



SiO2/Al2O3
4.40 to 4.90



Al2O3/CaO
0.52 to 0.57



SiO2 + Al2O3
69.52 to 72.05 wt %



SiO2 − RO
32.40 to 32.70 wt %



Al2O3/RO
0.47 to 0.51



R2O + RO + B2O3
26.10 to 27.30 wt %



(SiO2 + Al2O3)/(R2O + RO + B2O3)
2.59 to 2.74










The glass compositions have a log 3 forming temperature of in the range of 1219 to 1241° C., and a ΔT in the range of 52 to 76° C.

Table 20 (Production Glasses) Table 20 is a representation of commercial glasses having embodiments of the invention similar to the embodiment of the glass compositions of Table 4. The glass compositions are of a quaternary system that includes SiO2 in the range of 55.97–57.07 wt %; Al2O3 in the range of 12.68–12.86 wt %; CaO in the range of 23.91–24.69 wt % and MgO in the range of 2.42–2.60 wt %. The compositions of Table 20 include B2O3 in the range of 1.15–1.70 wt %; TiO2 in the range of 0.94–1.09 wt %; Na2O in the range of 0.87–0.93 wt %; K2O in the range of greater than 0.050–0.070 wt %; SrO in the range of 0.040–0.050 wt %; Cr2O3 in the range of 0.002–0.008 wt %; SO3 in the range of 0.018–0.032 wt %, and Fe2O3 in the range of 0.255–0.278 wt %.
A glass composition having ingredients of Tables 20 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature in the range of 1203–1217° C. and a delta T in the range of 55–83° C. Several of the glass compositions do not have the forming and liquidus temperatures, and the delta T. The glass compositions without the temperatures and delta T were glass compositions made between glass compositions whose forming temperature, liquidus temperature and delta T were measured. As indicated by the position on the Table which is in general in chronological order, it is expected that the glass compositions not measured would have temperature performances similar to those that were measured. The mathematical relationships of the ingredients of the glass compositions on Table 20 are listed on Table 22 in the column entitled “Production Glasses (contain boron)”. The R2O from the listed Production Glasses is equal to the sum in wt % of Li2O and Na2O.
As can now be appreciated, a range for each of the ingredients of the glass compositions of Types 1 and 2 glasses (Tables 2–11) can be determined from Tables. More particularly, Tables 1 and 2 provide a quaternary system including SiO2, Al203, CaO and MgO and the ingredients of the glass having the relationship as shown in Table 22 under the column entitled “Types 1 & 2 Glasses”. Types 1 & 2 Glasses included K2O and Na2O; therefore R2O is equal to the sum in wt % of K2O and Na2O.
The glass compositions having the following ingredients in the following ranges has a log 3 forming temperature in the range of 1167 to 1240° C. and a ΔT in the range of 50 to 100° C.:
















SiO2
53.00 to 59.05 percent by weight;



Al2O3
12.20 to 14.00 percent by weight;



CaO
22.25 to 24.95 percent by weight, and



MgO
1.50 to 3.00 percent by weight, and










the composition may further include:

















TiO2
0.50 to 1.10 percent by weight;



Na2O
0.45 to 0.90 percent by weight;



K2O
0 to 0.58 percent by weight;



Fe2O3
0 to 0.50 percent by weight, and



B2O3
0 to 5.02 percent by weight.










Further as can be appreciated, a range for each of the ingredients for Type 3–6 glasses on Tables 12–19 can be determined by selecting the lowest and highest values to define the range for an ingredient and/or relationship on Tables 12–19. More particularly Tables 12–19 provide glass compositions having a quaternary system including SiO2, Al2O3, CaO and Mgo with the ingredients of the glass having the relationship shown on Table 22 under the column entitled “Types 3–6 Glasses”. Types 3–6 Glasses included Li2O, K2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O, K2O and Na2O.
The glass composition having the following ingredients in the following ranges has a log 3 forming temperature in the range of 1187 to 1240° C. and a delta T in the range of 50 to 142° C.:
















SiO2
54.60 to 60.75 percent by weight;



Al2O3
11.90 to 13.64 percent by weight;



CaO
22.00 to 24.22 percent by weight, and



MgO
1.90 to 3.40 percent by weight, and










the composition may further include:

















TiO2
0.49 to 1.50 percent by weight;



Na2O
0 to 0.90 percent by weight;



K2O
0 to 0.10 percent by weight;



ZnO
0.45 to 1.50 percent by weight;



Li2O
0.30 to 1.00 percent by weight;



Fe2O3
0 to 0.35 percent by weight, and



B2O3
0 to 3.00 percent by weight.










Still further as can be appreciated, a range for each of the ingredients for boron free glasses: Type 1 Glasses (Table 2), Type 3 Glasses (Tables 12 and 13); Type 4 Glasses (Tables 14 and 15); Type 5 Glasses (Table 16) and their relationship can be determined from Tables 2 and 12–16. More particularly, Tables 2 and 12–16 glass compositions having a quaternary system including SiO2, Al2O3, CaO and Mgo with the ingredients of the glass having the relationship shown on Table 22 under the column entitled “Types 1 & 3–5 Glasses”. Types 1 & 3–5 Glasses included Li2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O and Na2O. Further Types 13&5 Glasses are boron free, therefore the formula “R2O+RO+B2O3” becomes “R2O+RO”.
The glass compositions having the following ingredients in the following ranges has a log 3 forming temperature in the range of 1195 to 1240° C. and a delta T in the range of 50 to 100° C.:
















SiO2
57.45 to 60.75 percent by weight;



Al2O3
12.00 to 13.68 percent by weight;



CaO
22.00 to 24.50 percent by weight;



MgO
1.70 to 3.10 percent by weight, and










the composition may further include:

















TiO2
0.50 to 1.50 percent by weight;



Na2O
0 to 0.91 percent by weight;



ZnO
0 to 1.00 percent by weight;



Li2O
0 to 1.00 percent by weight, and



Fe2O3
0 to 0.35 percent by weight.










Still further as can be appreciated, a range for each of the ingredients for boron containing: Type 2 Glasses (Tables 3–11) and Type 6 Glasses (Tables 17 and 18) and their relationship can be determined from Tables 3–11, 17 and 18. More particularly, Tables 3–11, 17 and 18 glass compositions having a boron containing (for example up to 5.05 wt %) quaternary system including SiO2, Al2O3, CaO and MgO with the ingredients of the glass having the relationship shown on Table 22 under the column entitled “Types 2 & 6 Glasses”. Types 2 & 6 Glasses included Li2O, K2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O, K2O and Na2O.
The glass compositions having the following ingredients in the following ranges has a log 3 forming temperature in the range of 1167 to 1240° C. and a delta T in the range of 50 to 142° C.:
















SiO2
53.00 to 59.53 percent by weight;



Al2O3
12.00 to 14.00 percent by weight;



CaO
22.25 to 24.95 percent by weight, and



MgO
1.50 to 3.00 percent by weight, and










the composition may further include:

















TiO2
0.40 to 1.10 percent by weight;



Na2O
0 to 0.90 percent by weight;



K2O
0 to 0.30 percent by weight;



F
0 to 0.50 percent by weight;



SrO
0 to 0.13 percent by weight;



Cr2O3
0 to 0.13 percent by weight;



Li2O
0 to 0.91 percent by weight, and



Fe2O3
0 to 0.30 percent by weight.










It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. For example, but not limiting thereto, one, two, three or more or all of the formulas discussed above setting forth the mathematical relationship of the ingredients may be used to identify properties of a glass composition. Based on the description of the embodiments of the invention, it can be appreciated that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications that are within the spirit and scope of the invention, as defined by the appended claims.









TABLE 1









Examples














Components (wt %)
A
B
C
D
E
F
G

















SiO2
55.60
56.45
55.70
57.60
56.35
56.70
57.85


Al2O3
13.58
13.25
13.94
12.35
13.45
13.67
12.55


CaO
24.76
24.75
24.80
24.40
24.65
23.87
24.45


MgO
2.80
2.55
2.55
2.55
2.55
2.62
2.55


TiO2
0.55
0.55
0.55
0.55
0.55
0.34
0.05


Na2O
0.45
0.45
0.45
0.45
0.45
0.44
0.45


K2O
0.58
0.45
0.45
0.45
0.45
0.51
0.45


Fe2O3
0.38
0.25
0.25
0.25
0.25
0.35
0.35


B2O3
1.30
1.30
1.30
1.30
1.30
1.50
1.30


RO (CaO + MgO)
27.56
27.30
27.35
26.95
27.20
26.49
27.00


SiO2/CaO
2.25
2.28
2.25
2.36
2.29
2.38
2.37


SiO2/RO
2.02
2.07
2.04
2.14
2.07
2.14
2.14


SiO2/Al2O3
4.09
4.26
4.00
4.66
4.19
4.15
4.61


Al2O3/CaO
0.55
0.54
0.56
0.51
0.55
0.57
0.51


SiO2 + Al2O3
69.18
69.70
69.64
69.95
69.80
70.37
70.44


R2O + RO + B2O3
29.89
29.50
29.55
29.15
29.40
28.94
29.20


(Si + Al)/(R2O + RO + B)
2.31
2.36
2.36
2.40
2.37
2.43
2.41


SiO2 − RO
28.04
29.15
28.35
30.65
29.15
30.21
30.85


Al2O3/RO
0.49
0.49
0.51
0.46
0.49
0.52
0.46


Log3 FT, ° C.
1213
1220
1220
1221
1221
1218
1219


Liquidus T, ° C.
1159
1160
1165
1164
1156
1160
1167


Delta T, ° C.
54
60
55
57
65
58
52
















TABLE 2







Type 1 Glasses









Examples















Components (wt %)
H
I
1
2
3
4
5
6


















SiO2
57.60
58.18
57.75
57.45
57.65
58.05
57.95
59.05


Al2O3
13.55
13.68
13.20
13.40
13.40
13.40
13.20
12.20


CaO
24.50
23.75
24.25
24.35
24.15
23.75
24.05
23.95


MgO
2.55
2.58
2.55
2.55
2.55
2.55
2.55
2.55


TiO2
0.55
0.55
1.10
1.10
1.10
1.10
1.10
1.10


Na2O
0.90
0.91
0.90
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.35
0.35
0.25
0.25
0.25
0.25
0.25
0.25


B2O3
—
—
—
—
—
—
—
—


RO (CaO + MgO)
27.05
26.33
26.80
26.90
26.70
26.30
26.60
26.50


SiO2/CaO
2.35
2.45
2.38
2.36
2.39
2.44
2.41
2.47


SiO2/RO
2.13
2.20
2.15
2.14
2.16
2.21
2.18
2.23


SiO2/Al2O3
4.25
4.25
4.38
4.29
4.30
4.33
4.39
4.84


Al2O3/CaO
0.55
0.58
0.54
0.55
0.56
0.56
0.55
0.51


SiO2 + Al2O3
71.15
71.86
70.95
70.85
71.05
71.45
71.15
71.25


R2O + RO + B2O3
27.95
27.24
27.70
27.80
27.60
27.20
27.50
27.40


(Si + Al)/(R2O + RO + B)
2.55
2.64
2.56
2.55
2.57
2.63
2.59
2.60


SiO2 − RO
30.55
31.85
30.95
30.55
30.95
31.75
31.35
32.55


Al2O3/RO
0.50
0.52
0.49
0.50
0.50
0.51
0.50
0.46


Log3 FT, ° C.
1240
1238
1232
1238
1240
1240
1235
1239


Liquidus T, ° C.
1185
1183
1166
1165
1166
1167
1164
1181


Delta T, ° C.
55
55
66
73
74
73
71
58
















TABLE 3







Type 2 Glasses









Examples













Components (wt %)
7
8
9
10
11
12
















SiO2
56.00
56.40
56.35
56.65
56.20
56.50


Al2O3
13.60
13.40
13.60
13.05
13.60
13.20


CaO
24.25
24.05
23.85
23.50
24.05
23.50


MgO
2.50
2.50
2.55
2.55
2.50
2.55


TiO2
0.50
0.50
0.50
1.10
0.50
1.10


Na2O
0.90
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.25
0.25
0.25
0.25
0.25
0.25


B2O3
2.00
2.00
2.00
2.00
2.00
2.00


RO (CaO + MgO)
26.75
26.55
26.40
26.05
26.55
26.05


SiO2/CaO
2.31
2.35
2.36
2.41
2.34
2.40


SiO2/RO
2.09
2.12
2.13
2.17
2.12
2.17


SiO2/Al2O3
4.12
4.21
4.14
4.34
4.13
4.28


Al2O3/CaO
0.56
0.56
0.57
0.56
0.57
0.56


SiO2 + Al2O3
69.60
69.80
69.95
69.70
69.80
69.70


R2O + RO + B2O3
29.65
29.45
29.30
28.95
29.45
28.95


(Si + Al)/(R2O + RO + B)
2.35
2.37
2.39
2.41
2.37
2.41


SiO2 − RO
29.25
29.85
29.95
30.60
29.65
30.45


Al2O3/RO
0.51
0.50
0.52
0.50
0.51
0.51


Log3 FT, ° C.
1213
1216
1218
1218
1219
1220


Liquidus T, ° C.
1136
1143
1138
1131
1136
1133


Delta T, ° C.
59
56
62
69
65
69
















TABLE 4







Type 2 Glasses









Examples

















Components (wt %)
13
14
15
16
17
18
19
20
21
22




















SiO2
56.25
56.45
56.75
56.50
56.75
57.5
56.75
57.75
57.75
57.75


Al2O3
13.2
13.20
13.20
13.20
13.20
12.2
13.2
12.2
12.2
12.2


CaO
24.25
24.25
23.95
24.00
23.75
24
23.95
23.75
23.75
23.95


MgO
2.55
2.55
2.55
2.55
2.55
2.55
2.55
2.55
2.55
2.55


TiO2
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10


Na2O
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25


B2O3
1.30
1.30
1.30
1.30
1.40
1.30
1.20
1.40
1.30
1.40


RO (CaO + MgO)
26.80
26.80
26.50
26.55
26.30
26.55
26.50
26.30
26.30
26.50


SiO2/CaO
2.32
2.33
2.37
2.35
2.39
2.40
2.37
2.43
2.43
2.41


SiO2/RO
2.10
2.11
2.14
2.13
2.16
2.17
2.14
2.20
2.20
2.18


SiO2/Al2O3
4.26
4.28
4.30
4.28
4.30
4.71
4.30
4.73
4.73
4.73


Al2O3/CaO
0.54
0.54
0.55
0.55
0.56
0.51
0.55
0.51
0.51
0.51


SiO2 + Al2O3
69.45
69.65
69.95
69.70
69.95
69.70
69.95
69.95
69.95
69.95


R2O + RO + B2O3
29.00
29.00
28.70
28.75
28.60
28.75
28.60
28.60
28.50
28.80


(Si + Al)/(R2O + RO + B)
2.39
2.40
2.44
2.42
2.45
2.42
2.45
2.45
2.45
2.43


SiO2 − RO
29.45
29.65
30.25
29.95
30.45
30.95
30.25
31.45
31.45
31.25


Al2O3/RO
0.49
0.49
0.50
0.50
0.50
0.46
0.50
0.46
0.46
0.46


Log3 FT, ° C.
1210
1214
1215
1215
1215
1216
1216
1217
1217
1218


Liquidus T, ° C.
1154
1159
1154
1154
1160
1152
1147
1151
1147
1155


Delta T, ° C.
56
55
61
61
55
64
69
66
70
63
















TABLE 5







Type 2 Glasses









Examples

















Components (wt %)
23
24
25
26
27
28
29
30
31
32




















SiO2
55.40
55.40
55.19
55.40
56.05
55.85
56.00
55.90
55.40
55.19


Al2O3
13.60
13.60
13.59
13.60
13.10
13.38
13.37
13.37
13.80
13.59


CaO
24.50
24.50
24.55
24.50
24.55
24.67
24.53
24.63
24.50
24.55


MgO
2.95
2.95
2.86
2.95
2.75
2.55
2.55
2.55
2.75
2.86


TiO2
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10


Na2O
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45


K2O
0.45
0.45
0.58
0.45
0.45
0.45
0.45
0.45
0.45
0.58


Fe2O3
0.25
0.25
0.38
0.25
0.25
0.25
0.25
0.25
0.25
0.38


B2O3
1.30
1.30
1.30
1.30
1.30
1.30
1.30
1.30
1.30
1.30


RO (CaO + MgO)
27.45
27.45
27.41
27.45
27.30
27.22
27.08
27.18
27.25
27.41


SiO2/CaO
2.26
2.26
2.25
2.26
2.28
2.26
2.28
2.27
2.26
2.25


SiO2/RO
2.02
2.02
2.01
2.02
2.05
2.05
2.07
2.06
2.03
2.01


SiO2/Al2O3
4.07
4.07
4.06
4.07
4.28
4.17
4.19
4.18
4.01
4.06


Al2O3/CaO
0.56
0.56
0.55
0.56
0.53
0.54
0.55
0.54
0.56
0.55


SiO2 + Al2O3
69.00
69.00
68.78
69.00
69.15
69.23
69.37
69.27
69.20
68.78


R2O + RO + B2O3
29.65
29.65
29.74
29.65
29.50
29.42
29.28
29.38
29.45
29.74


(Si + Al)/(R2O + RO + B)
2.33
2.33
2.31
2.33
2.34
2.35
2.37
2.36
2.35
2.31


SiO2 − RO
27.95
27.95
27.78
27.95
28.75
28.63
28.92
28.72
28.15
27.78


Al2O3/RO
0.50
0.50
0.50
0.50
0.48
0.49
0.49
0.49
0.51
0.50


Log3 FT, ° C.
1210
1211
1216
1217
1218
1220
1221
1221
1221
1222


Liquidus T, ° C.
1157
1151
1154
1167
1156
1148
1157
1142
1167
1154


Delta T, ° C.
53
60
62
56
62
72
64
79
54
63
















TABLE 6







Type 2 Glasses









Examples

















Components (wt %)
33
34
35
36
37
38
39
40
41
42




















SiO2
56.60
56.50
56.50
55.95
57.60
56.50
56.45
56.50
56.55
56.15


Al2O3
13.25
13.45
13.45
13.95
12.35
13.49
13.48
13.45
13.35
13.35


CaO
24.60
24.50
24.50
24.55
24.40
24.46
24.52
24.50
24.55
24.95


MgO
2.55
2.55
2.55
2.55
2.55
2.55
2.55
2.55
2.55
2.55


TiO2
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55


Na2O
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.25
0.25
0.25
0.25
0.35
0.25
0.25
0.25
0.25
0.25


B2O3
1.30
1.30
1.30
1.30
1.30
1.30
1.30
1.30
1.30
1.30


RO (CaO + MgO)
27.15
27.05
27.05
27.10
26.95
27.01
27.07
27.05
27.10
27.50


SiO2/CaO
2.30
2.31
2.31
2.28
2.36
2.31
2.30
2.31
2.30
2.25


SiO2/RO
2.08
2.09
2.09
2.06
2.14
2.09
2.09
2.09
2.09
2.04


SiO2/Al2O3
4.27
4.20
4.20
4.01
4.66
4.19
4.19
4.20
4.24
4.21


Al2O3/CaO
0.54
0.55
0.55
0.57
0.51
0.55
0.55
0.55
0.54
0.54


SiO2 + Al2O3
69.85
69.95
69.95
69.90
69.95
69.99
69.93
69.95
69.90
69.50


R2O + RO + B2O3
29.35
29.25
29.25
29.30
29.15
29.21
29.27
29.25
29.30
29.70


(Si + Al)/(R2O + RO + B)
2.38
2.39
2.39
2.39
2.40
2.40
2.39
2.39
2.39
2.34


SiO2 − RO
29.45
29.45
29.45
28.85
30.65
29.49
29.38
29.45
29.45
28.65


Al2O3/RO
0.49
0.50
0.50
0.51
0.46
0.50
0.50
0.50
0.49
0.49


Log3 FT, ° C.
1211
1212
1215
1216
1216
1218
1219
1220
1220
1220


Liquidus T, ° C.
1153
1158
1157
1162
1164
1161
1158
1160
1155
1154


Delta T, ° C.
58
54
58
54
52
57
61
60
65
66
















TABLE 7







Type 2 Glasses









Examples

















Components (wt %)
43
44
45
46
47
48
49
50
51
52




















SiO2
55.50
55.25
55.25
55.5
55.00
55.75
55.75
55.75
56.00
56.15


Al2O3
13.20
13.20
13.30
13.30
13.20
13.30
13.20
13.20
13.30
13.05


CaO
23.50
23.75
24.20
23.95
24.00
23.70
23.25
23.25
23.45
23.00


MgO
2.55
2.55
2.55
2.55
2.55
2.55
2.55
2.55
2.55
2.55


TiO2
1.10
1.10
0.55
0.55
1.10
0.55
1.10
1.10
0.55
1.10


Na2O
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25


B2O3
3.00
3.00
3.00
3.00
3.00
3.00
3.00
3.00
3.00
3.00


RO (CaO + MgO)
26.05
26.30
26.75
26.50
26.55
26.25
25.80
25.80
26.00
25.55


SiO2/CaO
2.36
2.33
2.28
2.32
2.29
2.35
2.40
2.40
2.39
2.44


SiO2/RO
2.13
2.10
2.07
2.09
2.07
2.12
2.16
2.16
2.15
2.20


SiO2/Al2O3
4.20
4.19
4.15
4.17
4.17
4.19
4.22
4.22
4.21
4.30


Al2O3/CaO
0.56
0.56
0.55
0.56
0.55
0.56
0.57
0.57
0.57
0.57


SiO2 + Al2O3
68.70
68.45
68.55
68.80
68.20
69.05
68.95
68.95
69.30
69.20


R2O + RO + B2O3
29.95
30.20
30.65
30.40
30.45
30.15
29.70
29.70
29.90
29.45


(Si + Al)/(R2O + RO + B)
2.29
2.27
2.24
2.26
2.24
2.29
2.32
2.32
2.32
2.35


SiO2 − RO
29.45
28.95
28.50
29.00
28.45
29.50
29.95
29.95
30.00
30.60


Al2O3/RO
0.51
0.50
0.50
0.50
0.50
0.51
0.51
0.51
0.51
0.51


Log3 FT, ° C.
1193
1198
1198
1200
1201
1201
1204
1204
1207
1212


Liquidus T, ° C.
1129
1122
1128
1129
1127
1127
1127
1123
1127
1122


Delta T, ° C.
64
76
70
71
74
74
77
81
80
90
















TABLE 8





Type 2 Glasses

















Examples


















Components (wt %)
53
54
55
56
57
58
59
60
61
62
63





SiO2
54.20
54.50
54.12
55.00
54.5
54.5
54.7
54.50
54.20
54.50
54.80


Al2O3
13.35
13.25
13.30
13.25
13.25
13.25
13.2
13.25
13.35
13.25
13.25


CaO
24.55
24.55
24.55
24.25
24.55
24.55
24.5
24.55
24.55
24.55
24.25


MgO
2.55
2.55
3.00
2.55
2.67
2.67
2.55
2.65
2.85
2.65
2.55


TiO2
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55


Na2O
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45


K2O
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55


Fe2O3
0.28
0.28
0.28
0.28
0.28
0.28
0.28
0.28
0.28
0.28
0.28


B2O3
3.00
3.00
3.00
3.00
3.00
3.00
3.00
3.00
3.00
3.00
3.00


F
0.20
0.20
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.20


SrO
0.12
0.12
0.10
0.12
0.10
0.10
0.12
0.12
0.12
0.12
0.12


RO (CaO + MgO)
27.10
27.10
27.55
26.80
27.22
27.22
27.05
27.20
27.40
27.20
26.80


SiO2/CaO
2.21
2.22
2.20
2.27
2.22
2.22
2.23
2.22
2.21
2.22
2.26


SiO2/RO
2.00
2.01
1.96
2.05
2.00
2.00
2.02
2.00
1.98
2.00
2.04


SiO2/Al2O3
4.06
4.11
4.07
4.15
4.11
4.11
4.14
4.11
4.06
4.11
4.14


Al2O3/CaO
0.54
0.54
0.54
0.55
0.54
0.54
0.54
0.54
0.54
0.54
0.55


SiO2 + Al2O3
67.55
67.75
67.42
68.25
67.75
67.75
67.90
67.75
67.55
67.75
68.05


R2O + RO + B2O3
31.10
31.10
31.55
30.80
31.22
31.22
31.05
31.20
31.40
31.20
30.80


(Si + Al)/(R2O + RO + B)
2.17
2.18
2.14
2.22
2.17
2.17
2.19
2.17
2.15
2.17
2.21


SiO2 − RO
27.10
27.40
26.57
28.20
27.28
27.28
27.65
27.30
26.80
27.30
28.00


Al2O3/RO
0.49
0.49
0.48
0.49
0.49
0.49
0.49
0.49
0.49
0.49
0.49


Log3 FT, ° C.
1190
1194
1196
1197
1201
1199
1201
1196
1196
1197
1197


Liquidus T, ° C.
1120
1124
1132
1124
1131
1137
1119
1130
1130
1127
1121


Delta T, ° C.
70
70
64
73
70
62
82
66
66
70
76












Examples


















Components (wt %)
64
65
66
67
68
69
70
71
721
73
74





SiO2
55.05
54.95
54.20
55.25
54.8
55.25
54.95
54.75
54.55
54.80
54.70


Al2O3
13.25
13.25
13.35
13.30
13.25
13.30
13.25
13.20
13.40
13.20
13.30


CaO
24.20
24.3
24.55
24.20
24.25
24.20
24.30
24.45
24.45
24.40
24.40


MgO
2.55
2.55
2.85
2.55
2.55
2.55
2.55
2.55
2.55
2.55
2.55


TiO2
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55
0.55


Na2O
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45
0.45


K2O
0.55
0.55
0.55
0.45
0.55
0.45
0.55
0.55
0.55
0.55
0.55


Fe2O3
0.28
0.28
0.28
0.25
0.28
0.25
0.28
0.28
0.28
0.28
0.28


B2O3
3.00
3.00
3.00
3.00
3.00
3.00
3.00
3.00
3.00
3.00
3.00


F
0.10
0.10
0.10
—
0.20
—
—
0.10
0.10
0.10
0.10


SrO
0.12
0.12
0.12
—
0.12
—
0.12
0.12
0.12
0.12
0.12


RO (CaO + MgO)
26.75
26.85
27.40
26.75
26.80
26.75
26.85
27.00
27.00
26.95
26.95


SiO2/CaO
2.27
2.26
2.21
2.28
2.26
2.28
2.26
2.24
2.23
2.25
2.24


SiO2/RO
2.06
2.05
1.98
2.07
2.04
2.07
2.05
2.03
2.02
2.03
2.03


SiO2/Al2O3
4.15
4.15
4.06
4.15
4.14
4.15
4.15
4.15
4.07
4.15
4.11


Al2O3/CaO
0.55
0.55
0.54
0.55
0.55
0.55
0.55
0.54
0.55
0.54
0.55


SiO2 + Al2O3
68.30
68.20
67.55
68.55
68.05
68.55
68.20
67.95
67.95
68.00
68.00


R2O + RO + B2O3
30.75
30.85
31.40
30.65
30.80
30.65
30.85
31.00
31.00
30.95
30.95


(Si + Al)/(R2O + RO + B)
2.22
2.21
2.15
2.24
2.21
2.24
2.21
2.19
2.19
2.20
2.20


SiO2 − RO
28.30
28.10
26.80
28.50
28.00
28.50
28.10
27.75
27.55
27.85
27.75


Al2O3/RO
0.50
0.49
0.49
0.50
0.49
0.50
0.49
0.49
0.50
0.49
0.49


Log3 FT, ° C.
1198
1198
1199
1202
1202
1203
1203
1203
1203
1204
1204


Liquidus T, ° C.
1127
1123
1137
1126
1147
1124
1125
1125
1124
1121
1122


Delta T, ° C.
71
75
62
76
55
79
78
78
79
83
82
















TABLE 9







Type 2 Glasses









Examples












Components (wt %)
75
76
77
















SiO2
53.00
53.00
53.50



Al2O3
13.10
13.50
14.00



CaO
24.00
24.00
24.00



MgO
2.50
2.50
1.50



TiO2
0.50
0.50
0.50



Na2O
0.90
0.90
0.90



K2O
0.37
0.37
0.37



Fe2O3
0.10
0.10
0.10



B2O3
5.02
4.93
4.94



F
0.50
0.50
0.50



SrO
0.13
0.13
0.13



Cr2O3
0.13
0.13
0.13



RO (CaO + MgO)
26.50
26.50
25.50



SiO2/CaO
2.21
2.21
2.23



SiO2/RO
2.00
2.00
2.10



SiO2/Al2O3
4.05
3.93
3.82



Al2O3/CaO
0.55
0.56
0.58



SiO2 + Al2O3
66.10
66.50
67.50



R2O + RO + B2O3
32.79
32.70
31.71



(Si + Al)/
2.02
2.03
2.13



(R2O + RO + B)



SiO2 − RO
26.50
26.50
28.00



Al2O3/RO
0.49
0.51
0.55



Log3 FT, ° C.
1167
1172
1177



Liquidus T, ° C.
1110
1103
1122



Delta T, ° C.
57
69
57

















TABLE 10





Type 2 Glasses

















Examples



















Components (wt %)
78
79
80
81
82
83
84
85
86
87
88
89





SiO2
55.40
55.80
56.20
55.75
56.35
55.60
55.80
56.40
56.0
56.00
56.00
56.65


Al2O3
13.60
13.40
13.60
13.20
13.60
13.60
13.60
13.40
13.60
13.80
13.60
13.05


CaO
24.85
24.65
24.05
23.25
23.85
24.65
24.45
24.05
24.25
24.05
24.25
23.50


MgO
2.50
2.50
2.50
2.55
2.55
2.50
2.50
2.50
2.50
2.50
2.50
2.55


TiO2
0.50
0.50
0.50
1.10
0.50
0.50
0.50
0.50
0.50
0.50
0.50
1.10


Na2O
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25


B2O3
2.00
2.00
2.00
3.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00


RO
27.35
27.15
26.55
25.80
26.40
27.15
26.95
26.55
26.75
26.55
26.75
26.05


SiO2/CaO
2.23
2.25
2.34
2.40
2.36
2.26
2.28
2.35
2.31
2.33
2.31
2.41


SiO2/RO
2.03
2.06
2.12
2.16
2.13
2.05
2.07
2.12
2.09
2.11
2.09
2.17


SiO2/Al2O3
4.07
4.16
4.13
4.22
4.14
4.09
4.10
4.21
4.12
4.06
4.11
4.34


Al2O3/CaO
0.54
0.54
0.57
0.57
0.57
0.55
0.56
0.55
0.56
0.57
0.56
0.56


SiO2 + Al2O3
69.00
69.20
69.80
68.95
69.95
69.20
69.40
69.80
69.60
69.80
69.60
69.70


R2O + RO + B2O3
30.25
30.05
29.45
29.70
29.30
30.05
29.85
29.45
29.65
29.45
29.65
28.95


(Si + Al)/(R2O + RO + B)
2.28
2.30
2.37
2.32
2.39
2.30
2.32
2.37
2.35
2.37
2.35
2.41


SiO2 − RO
28.05
28.65
29.65
29.95
29.95
28.45
28.85
29.85
29.25
29.45
29.25
30.60


Al2O3/RO
0.50
0.49
0.51
0.51
0.51
0.50
0.50
0.50
0.51
0.52
0.51
0.50


Log3 FT, ° C.
1217
1211
1219
1204
1218
1211
1209
1216
1213
1219
1202
1218


Liquidus T, ° C.
1153
1156
1136
1127
1138
1154
1156
1143
1136
1151
1137
1131


Delta T, ° C.
64
55
83
77
80
57
53
73
77
68
65
87













Examples


















Components (wt %)
90
91
92
93
94
95
96
97
98
99





SiO2
56.25
56.15
57.75
57.75
56.75
57.15
57.25
58.55
57.25
56.25


Al2O3
13.20
13.05
13.20
12.20
13.20
13.05
13.20
12.20
12.20
13.20


CaO
23.25
23.00
24.25
24.25
24.25
24.00
24.25
23.45
23.75
23.75


MgO
2.55
2.55
2.50
2.50
2.50
2.55
2.50
2.55
2.50
2.50


TiO2
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10


Na2O
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25


B2O3
3.00
3.00
1.00
1.00
1.00
1.00
1.00
1.00
2.00
2.00


RO
25.80
25.55
26.75
26.75
26.75
26.55
26.75
26.00
26.25
26.25


SiO2/CaO
2.41
2.44
2.38
2.38
2.34
2.38
2.36
2.50
2.41
2.37


SiO2/RO
2.18
2.20
2.16
2.16
2.12
2.15
2.14
2.25
2.18
2.14


SiO2/Al2O3
4.26
4.30
4.38
4.73
4.30
4.38
4.33
4.80
4.69
4.26


Al2O3/CaO
0.56
0.56
0.54
0.50
0.54
0.54
0.54
0.52
0.51
0.56


SiO2 + Al2O3
69.45
69.20
70.95
69.95
69.95
70.20
70.45
70.75
69.45
69.45


R2O + RO + B2O3
29.70
29.45
28.65
28.65
28.65
28.45
28.65
27.90
29.15
29.15


(Si + Al)/(R2O + RO + B)
2.34
2.34
2.67
2.44
2.44
2.47
2.47
2.54
2.38
2.38


SiO2 − RO
30.45
30.60
31.00
31.00
30.00
30.60
30.50
32.55
31.00
30.00


Al2O3/RO
0.51
0.51
0.49
0.46
0.49
0.49
0.49
0.47
0.46
0.50


Log3 FT, ° C.
1214
1212
1240
1227
1228
1235
1239
1236
1227
1224


Liquidus T, ° C.
1114
1178
1178
1164
1161
1154
1159
1159
1148
1149


Delta T, ° C.
100
34
62
63
67
81
80
77
79
75













Examples


















Components (wt %)
100
101
102
103
104
105
106
107
108
109





SiO2
56.65
56.75
58.05
55.80
57.25
56.75
56.25
56.50
55.80
56.75


Al2O3
13.05
13.20
12.20
13.60
13.20
13.20
13.20
13.20
13.80
13.20


CaO
23.50
23.25
22.95
24.45
22.75
23.75
23.75
23.50
24.25
22.25


MgO
2.55
2.55
2.55
2.50
2.50
2.05
2.55
2.55
2.50
2.55


TiO2
1.10
1.10
1.10
0.50
1.10
1.10
1.10
1.10
0.50
1.10


Na2O
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25


B2O3
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
3.00


RO
26.05
25.80
25.50
26.95
25.25
25.80
26.30
26.05
26.75
24.80


SiO2/CaO
2.41
2.44
2.53
2.28
2.52
2.39
2.37
2.40
2.30
2.55


SiO2/RO
2.17
2.20
2.28
2.07
2.27
2.20
2.14
2.16
2.09
2.29


SiO2/Al2O3
4.34
4.30
4.76
4.10
4.34
4.30
4.26
4.28
4.04
4.30


Al2O3/CaO
0.56
0.57
0.53
0.56
0.58
0.56
0.55
0.56
0.57
0.59


SiO2 + Al2O3
69.70
69.95
70.25
69.40
70.45
69.95
69.45
69.70
69.60
69.95


R2O + RO + B2O3
28.95
28.70
28.40
29.85
28.15
28.70
29.20
28.95
29.65
28.70


(Si + Al)/(R2O + RO + B)
2.41
2.44
2.47
2.32
2.50
2.44
2.38
2.41
2.35
2.44


SiO2 − RO
30.60
30.95
32.55
28.85
32.00
30.95
29.95
30.45
29.05
31.95


Al2O3/RO
0.50
0.51
0.48
0.50
0.52
0.51
0.50
0.51
0.52
0.53


Log3 FT, ° C.
1225
1225
1225
1222
1237
1230
1220
1220
1222
1221


Liquidus T, ° C.
1145
1147
1142
1153
1149
1141
1131
1133
1137
1121


Delta T, ° C.
80
78
83
69
86
89
89
87
85
100
















TABLE 11







Type 2 Glasses









Examples












Components (wt %)
110
111
112
















SiO2
57.75
57.75
56.10



Al2O3
12.2
12.2
13.38



CaO
23.75
23.95
24.42



MgO
2.55
2.55
2.55



TiO2
1.10
1.10
0.55



Na2O
0.90
0.90
0.90



K2O
—
—
—



Fe2O3
0.25
0.25
0.25



B2O3
1.40
1.40
1.30



RO (CaO + MgO)
26.30
26.50
26.97



SiO2/CaO
2.43
2.41
2.30



SiO2/RO
2.20
2.18
2.08



SiO2/Al2O3
4.73
4.73
4.19



Al2O3/CaO
0.51
0.51
0.54



SiO2 + Al2O3
69.95
69.95
69.48



R2O + RO + B2O3
28.60
28.80
29.17



(Si + Al)/
2.44
2.43
2.38



(R2O + RO + B)



SiO2 − RO
31.45
31.25
29.13



Al2O3/RO
0.46
0.46
0.50



Log3 FT, ° C.
1217
1218
1215



Liquidus T, ° C.
1151
1155
1150



Delta T, ° C.
66
63
65

















TABLE 12







Type 3 Glasses









Examples
















Components (wt %)
113
114
115
116
117
118
119
120
121



















SiO2
58.70
57.95
58.35
60.05
58.25
58.86
59.97
59.16
58.76


Al2O3
13.35
13.20
13.20
12.98
13.40
13.44
12.19
13.24
13.64


CaO
23.50
24.05
23.65
22.14
23.55
23.55
22.25
23.45
23.45


MgO
2.50
2.55
2.55
3.12
2.55
2.50
2.90
2.50
2.50


TiO2
0.50
1.10
1.10
0.55
1.10
0.50
1.50
0.50
0.50


Na2O
0.30
—
—
—
—
—
—
—
—


K2O
—
—
—
—
—
—
—
—
—


Li2O
0.90
0.90
0.90
0.91
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.20
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25


B2O3
—
—
—
—
—
—
—
—
—


RO (CaO + MgO)
26.00
26.60
26.20
25.26
26.10
26.05
25.15
25.95
25.95


SiO2/CaO
2.50
2.41
2.47
2.71
2.47
2.50
2.70
2.52
2.51


SiO2/RO
2.26
2.18
2.23
2.38
2.23
2.26
2.38
2.28
2.26


SiO2/Al2O3
4.40
4.39
4.42
4.63
4.35
4.38
4.92
4.47
4.31


Al2O3/CaO
0.57
0.55
0.56
0.59
0.57
0.57
0.55
0.56
0.58


SiO2 + Al2O3
72.05
71.15
71.55
73.03
71.65
72.30
72.16
72.40
72.40


R2O + RO + B2O3
27.20
27.50
27.10
26.17
27.00
26.95
26.05
26.85
26.85


(Si + Al)/(R2O + RO + B)
2.65
2.59
2.64
2.79
2.65
2.68
2.77
2.70
2.70


SiO2 − RO
32.70
31.35
32.15
34.79
32.15
32.81
34.82
33.21
32.81


Al2O3/RO
0.51
0.50
0.50
0.51
0.51
0.52
0.48
0.51
0.53


Log3 FT, ° C.
1211
1205
1211
1214
1215
1216
1217
1218
1218


Liquidus T, ° C.
1153
1151
1146
1159
1153
1153
1161
1156
1150


Delta T, ° C.
58
54
65
55
62
63
56
62
68
















TABLE 13





Type 3 Glasses

















Examples

















Components (wt %)
122
123
124
125
126
127
128
129
130
131





SiO2
58.70
59.30
57.65
58.96
58.15
60.09
60.21
60.33
59.73
59.85


Al2O3
13.35
12.10
13.40
13.24
13.20
12.22
12.24
12.27
12.92
12.95


CaO
23.50
22.60
24.15
23.65
23.85
23.31
23.35
23.40
22.00
22.04


MgO
2.50
3.40
2.55
2.50
2.55
2.70
2.50
2.30
3.10
2.90


TiO2
0.50
1.50
1.10
0.50
1.10
0.50
0.50
0.50
1.10
1.10


Na2O
0.60
0.45
—
—
—
—
—
—
—
—


Li2O
0.60
0.45
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.25
0.20
0.25
0.25
0.25
0.25
0.25
0.25
0.25
0.25


B2O3
—
—
—
—
—
—
—
—
—
—


RO (CaO + MgO)
26.00
26.00
26.70
26.15
26.40
26.01
25.85
25.70
25.10
24.94


SiO2/CaO
2.50
2.62
2.39
2.49
2.44
2.58
2.58
2.58
2.70
2.72


SiO2/RO
2.26
2.28
2.16
2.25
2.20
2.31
2.33
2.35
2.38
2.40


SiO2/Al2O3
4.40
4.90
4.30
4.45
4.41
4.92
4.92
4.92
4.62
4.62


Al2O3/CaO
0.57
0.54
0.55
0.56
0.55
0.52
0.52
0.52
0.59
0.59


SiO2 + Al2O3
72.05
71.40
71.05
72.20
71.35
72.31
72.45
72.60
72.65
72.80


R2O + RO + B2O3
27.20
27.45
27.60
27.05
27.30
26.91
26.75
26.60
26.00
25.84


(Si + Al)/(R2O + RO + B)
2.65
2.70
2.57
2.67
2.61
2.69
2.71
2.73
2.30
2.32


SiO2 − RO
32.7
33.30
30.95
32.81
31.75
34.08
34.36
34.63
34.63
34.91


Al2O3/RO
0.51
0.47
0.50
0.51
0.50
0.47
0.47
0.48
0.51
0.52


Log3 FT, ° C.
1226
1205
1206
1212
1237
1217
1213
1216
1214
1214


Liquidus T, ° C.
1157
1151
1154
1158
1172
1163
1162
1166
1164
1161


Delta T, ° C.
69
54
52
54
65
54
51
50
50
53












Examples

















Components (wt %)
132
133
134
135
136
137
138
139
140
141





SiO2
59.97
60.09
60.21
60.00
60.57
59.80
59.75
59.65
59.60
59.55


Al2O3
12.97
13.00
13.02
12.50
13.10
12.25
12.25
12.25
12.25
12.25


CaO
22.09
22.13
22.18
23.70
22.31
22.60
22.85
23.35
23.60
23.85


MgO
2.70
2.50
2.30
1.90
1.70
3.10
2.90
2.50
2.30
2.10


TiO2
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10
1.10


Na2O
—
—
—
—
—
0.30
0.30
0.30
0.30
0.30


Li2O
0.90
0.90
0.90
0.90
0.90
0.60
0.60
0.60
0.60
0.60


Fe2O3
0.25
0.25
0.25
0.25
0.25
—
—
—
—
—


B2O3
—
—
—
—
—
—
—
—
—
—


RO (CaO + MgO)
24.79
24.63
24.48
25.60
24.01
25.70
25.75
25.85
25.90
25.95


SiO2/CaO
2.71
2.71
2.71
2.53
2.71
2.64
2.61
2.57
2.52
2.50


SiO2/RO
2.42
2.44
2.46
2.34
2.52
2.33
2.32
2.31
2.30
2.29


SiO2/Al2O3
4.62
4.62
4.82
4.80
4.62
4.88
4.88
4.87
4.87
4.86


Al2O3/CaO
0.59
0.59
0.59
0.53
0.59
0.54
0.54
0.52
0.52
0.51


SiO2 + Al2O3
72.87
73.09
73.23
72.50
73.67
72.05
72.00
71.90
71.85
71.80


R2O + RO + B2O3
25.69
25.53
25.38
26.50
24.91
26.60
26.65
26.75
26.80
26.85


(Si + Al)/(R2O + RO + B)
2.33
2.86
2.89
2.74
2.96
2.71
2.70
2.69
2.68
2.67


SiO2 − RO
35.18
35.46
35.73
34.40
36.56
34.10
34.00
33.80
33.7
33.60


Al2O3/RO
0.47
0.53
0.53
0.49
0.55
0.47
0.48
0.47
0.47
0.47


Log3 FT, ° C.
1219
1223
1233
1239
1239
1240
1236
1236
1238
1234


Liquidus T, ° C.
1160
1155
1142
1139
1141
1156
1156
1159
1167
1173


Delta T, ° C.
59
68
91
100
98
94
80
77
71
61












Examples

















Components (wt %)
142
143
144
145
146
147
148
149
150
151





SiO2
59.50
60.00
59.95
59.90
59.85
60.21
60.33
60.75
60.21
59.71


Al2O3
12.25
12.40
12.40
12.40
12.0
12.24
12.27
12.35
13.02
13.24


CaO
24.10
22.05
23.30
23.55
23.80
22.34
22.39
22.55
22.52
22.90


MgO
1.90
2.30
2.10
1.90
1.70
2.50
2.30
1.70
2.50
2.50


TiO2
1.10
1.10
1.10
1.10
1.10
1.50
1.50
1.50
0.50
0.50


Na2O
0.30
—
—
—
—
—
—
—
—
—


Li2O
0.60
0.90
0.90
0.90
0.90
0.90
0.90
0.90
1.00
0.90


Fe2O3
—
0.25
0.25
0.26
0.25
0.25
0.25
0.25
0.25
0.25


B2O3
—
—
—
—
—
—
—
—
—
—


RO (CaO + MgO)
26.00
24.35
25.40
25.45
25.50
24.84
24.69
24.25
25.02
25.40


SiO2/CaO
2.47
2.72
2.57
2.54
2.51
2.70
2.69
2.69
2.67
2.61


SiO2/RO
2.29
2.46
2.36
2.35
2.35
2.42
2.44
2.51
2.41
2.35


SiO2/Al2O3
4.86
4.84
4.83
4.83
4.99
4.92
4.92
4.92
4.62
4.51


Al2O3/CaO
0.51
0.56
0.53
0.53
0.50
0.55
0.55
0.55
0.58
0.58


SiO2 + Al2O3
71.75
72.40
72.35
72.30
71.85
72.45
72.60
73.10
73.23
72.95


R2O + RO + B2O3
26.90
25.23
26.30
26.35
26.40
25.74
25.59
25.15
26.02
26.30


(Si + Al)/(R2O + RO + B)
2.67
2.87
2.75
2.74
2.72
2.81
2.83
2.91
2.81
2.77


SiO2 − RO
33.50
35.65
36.55
34.45
34.35
35.37
35.64
36.50
35.19
34.31


Al2O3/RO
0.47
0.51
0.53
0.49
0.47
0.49
0.50
0.50
0.52
0.52


Log3 FT, ° C.
1234
1230
1231
1224
1224
1215
1231
1240
1231
1227


Liquidus T, ° C.
1181
1146
1152
1156
1156
1162
1160
1166
1143
1142


Delta T, ° C.
53
84
79
68
68
53
71
74
88
85












Examples


















Components (wt %)
152
153
154
155
156
157
158
159
160
161
162





SiO2
59.46
60.02
60.26
60.14
60.10
60.23
60.10
60.23
60.14
60.05
60.05


Al2O3
13.24
12.35
12.40
12.37
13.00
12.25
13.00
12.25
12.37
12.98
12.98


CaO
23.15
23.35
23.45
23.40
22.15
23.36
22.15
23.36
23.40
22.14
22.14


MgO
2.50
2.54
2.55
2.54
2.50
2.50
2.50
2.50
2.54
3.12
3.12


TiO2
0.50
0.50
0.51
0.51
1.10
0.51
1.10
0.51
0.51
0.55
0.55


Na2O
—
—
—
—
—
—
—
—
—
—
—


Li2O
0.90
1.00
0.60
0.80
0.90
0.90
0.90
0.90
0.80
0.91
0.91


Fe2O3
0.25
0.23
0.23
0.23
0.25
0.25
0.25
0.25
0.23
0.25
0.25


B2O3
—
—
—
—
—
—
—
—
—
—
—


RO (CaO + MgO)
26.65
25.89
26.00
25.94
24.65
25.86
24.65
25.86
25.94
25.26
25.26


SiO2/CaO
2.57
2.57
2.57
2.57
2.71
2.58
2.71
2.58
2.57
2.71
2.71


SiO2/RO
2.32
2.32
2.32
2.32
2.44
2.33
2.44
2.33
2.32
2.38
2.38


SiO2/Al2O3
4.49
4.86
4.89
4.86
4.62
4.92
4.62
4.92
4.86
4.63
4.63


Al2O3/CaO
0.57
0.53
0.53
0.53
0.59
0.52
0.59
0.52
0.53
0.59
0.59


SiO2 + Al2O3
72.70
72.37
72.66
72.51
73.10
72.48
73.10
72.48
72.51
73.03
73.03


R2O + RO + B2O3
26.50
26.85
26.60
26.74
25.55
26.76
25.55
26.76
26.74
26.17
26.17


(Si + Al)/(R2O + RO + B)
2.74
2.70
2.73
2.71
2.86
2.71
2.86
2.71
2.71
2.79
2.79


SiO2 − RO
33.81
34.13
34.26
34.20
34.45
34.37
35.45
34.44
34.20
34.79
34.79


Al2O3/RO
0.52
0.48
0.48
0.48
0.53
0.47
0.53
0.47
0.48
0.51
0.51


Log3 FT, ° C.
1226
1209
1230
1219
1235
1220
1237
1224
1219
1219
1223


Liquidus T, ° C.
1147
1159
1158
1159
1133
1160
1136
1158
1159
1164
1163


Delta T, ° C.
79
50
72
60
102
60
101
66
60
55
60
















TABLE 14







Type 4 Glasses









Examples














Components (wt %)
163
164
165
166
167
168
169

















SiO2
58.30
58.20
58.10
58.15
58.15
58.00
58.25


Al2O3
13.03
13.03
13.03
13.20
13.33
13.03
13.33


CaO
23.54
23.64
23.74
22.85
23.39
23.84
23.29


MgO
2.50
2.50
2.50
2.55
2.50
2.50
2.50


TiO2
0.50
0.50
0.50
1.10
0.50
0.50
0.50


Li2O
0.90
0.90
0.90
0.90
0.90
0.90
0.90


ZnO
1.00
1.00
1.00
1.00
1.00
1.00
1.00


Fe2O3
0.23
0.23
0.23
0.25
0.23
0.23
0.23


B2O3
—
—
—
—
—
—
—


RO (CaO + MgO)
26.04
26.14
26.24
25.40
25.89
26.34
25.79


SiO2/CaO
2.48
2.46
2.45
2.54
2.49
2.43
2.50


SiO2/RO
2.24
2.23
2.21
2.29
2.25
2.20
2.26


SiO2/Al2O3
4.47
4.47
4.46
4.41
4.36
4.45
4.37


Al2O3/CaO
0.55
0.55
0.55
0.58
0.57
0.55
0.57


SiO2 + Al2O3
71.33
71.23
71.13
71.35
71.48
71.03
71.58


R2O + RO + B2O3
26.94
27.04
27.14
26.30
26.79
27.24
26.69


(Si + Al)/(R2O + RO + B)
2.65
2.63
2.62
2.71
2.67
2.61
2.68


SiO2 − RO
32.26
32.06
31.86
32.75
32.26
31.66
32.46


Al2O3/RO
0.50
0.50
0.50
0.52
0.51
0.49
0.52


Log3 FT, ° C.
1204
1205
1206
1207
1208
1208
1213


Liquidus T, ° C.
1147
1148
1144
1136
1152
1152
1146


Delta T, ° C.
57
57
62
71
56
56
67
















TABLE 15







Type 4 Glasses









Examples













Components (wt %)
170
171
172
173
174
175
















SiO2
58.00
58.10
57.35
57.95
59.61
59.47


Al2O3
13.03
13.63
13.20
13.20
12.16
12.16


CaO
23.84
23.14
23.65
24.05
23.50
24.22


MgO
2.50
2.50
2.55
2.55
2.50
1.90


TiO2
0.50
0.50
1.10
1.10
1.10
1.10


Li2O
0.90
0.90
0.90
0.90
0.45
0.45


ZnO
1.00
1.00
1.00
1.00
0.45
0.45


Fe2O3
0.23
0.23
0.25
0.25
—
—


B2O3
—
—
—
—
—
—


RO (CaO + MgO)
26.34
25.64
26.20
26.60
26.00
26.12


SiO2/CaO
2.43
2.51
2.42
2.41
2.54
2.46


SiO2/RO
2.20
2.26
2.19
2.18
2.29
2.28


SiO2/Al2O3
4.45
4.26
4.34
4.39
4.90
4.89


Al2O3/CaO
0.55
0.59
0.56
0.55
0.52
0.50


SiO2 + Al2O3
71.03
71.73
70.55
71.15
71.77
71.63


R2O + RO + B2O3
27.24
26.54
27.10
27.50
26.45
26.57


(Si + Al)/(R2O + RO + B)
2.61
2.70
2.60
2.60
2.71
2.70


SiO2 − RO
31.66
32.46
31.15
31.30
33.61
33.35


Al2O3/RO
0.49
0.53
0.50
0.50
0.47
0.47


Log3 FT, ° C.
1208
1212
1195
1195
1229
1218


Liquidus T, ° C.
1149
1157
1141
1140
1154
1159


Delta T, ° C.
59
55
54
55
75
59
















TABLE 16







Type 5 Glasses










Example












Components (wt %)
176
177















SiO2
59.00
58.70



Al2O3
12.00
11.90



CaO
22.50
22.4



MgO
3.40
3.40



TiO2
1.00
1.00



Na2O
0.90
0.90



ZnO
1.00
1.50



K2O
—
—



Fe2O3
0.20
0.20



B2O3
—
—



RO
25.90
25.80



SiO2/CaO
2.62
2.62



SiO2/RO
2.28
2.28



SiO2/Al2O3
4.92
4.93



Al2O3/CaO
0.53
0.53



SiO2 + Al2O3
71.00
70.60



R2O + RO + B2O3
26.80
26.70



(Si + Al)/
2.65
2.64



(R2O + RO + B)



SiO2 − RO
33.10
32.90



Al2O3/RO
0.46
0.46



Log3 FT ° C.
1234
1231



Liquidus T ° C.
1175
1181



Delta(T3-TL) ° C.
59
50

















TABLE 17







Type 6 Glasses









Examples

















Components (wt %)
178
179
180
181
182
183
184
185
186
187




















SiO2
58.00
58.10
58.30
57.90
58.11
57.60
58.50
57.80
58.00
57.80


Al2O3
13.03
13.03
13.03
13.23
13.36
13.23
12.76
13.43
13.03
13.03


CaO
23.84
23.74
23.54
23.74
23.40
23.84
23.61
23.64
23.84
23.84


MgO
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50


TiO2
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50


Na2O
—
—
—
—
—
0.10
—
—
—
—


K2O
—
—
—
—
—
—
—
—
—
—


Li2O
0.90
0.90
0.90
0.90
0.90
0.80
0.90
0.90
0.90
0.90


Fe2O3
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23


B2O3
1.00
1.00
1.00
1.00
1.00
1.20
1.00
1.00
1.00
1.20


RO (CaO + MgO)
26.34
26.24
26.04
26.24
25.90
26.34
26.11
26.14
26.34
26.34


SiO2/CaO
2.43
2.45
2.48
2.44
2.48
2.42
2.48
2.45
2.43
2.42


SiO2/RO
2.20
2.21
2.24
2.21
2.24
2.19
2.24
2.21
2.20
2.19


SiO2/Al2O3
4.45
4.46
4.47
4.38
4.35
4.35
4.58
4.30
4.45
4.44


Al2O3/CaO
0.55
0.55
0.55
0.56
0.57
0.55
0.54
0.57
0.55
0.55


SiO2 + Al2O3
71.03
71.13
71.33
71.13
71.47
70.83
71.26
71.23
71.03
70.83


R2O + RO + B2O3
28.24
28.14
27.94
28.14
27.80
28.44
28.01
28.04
28.24
28.44


(Si + Al)/(R2O + RO + B)
2.52
2.53
2.55
2.53
2.57
2.49
2.54
2.54
2.52
2.49


SiO2 − RO
31.66
31.86
32.26
31.66
32.21
31.26
32.39
31.66
31.66
31.46


Al2O3/RO
0.49
0.50
0.50
0.50
0.52
0.50
0.49
0.51
0.49
0.49


Log3 FT, ° C.
1192
1194
1195
1195
1196
1196
1197
1197
1198
1198


Liquidus T, ° C.
1137
1135
1140
1137
1133
1133
1139
1139
1138
1135


Delta T, ° C.
55
59
55
58
63
63
58
58
60
63
















TABLE 18





Type 6 Glasses

















Examples

















Components (wt %)
188
189
190
191
192
193
194
195
196*
197*





SiO2
58.00
57.90
58.15
58.25
58.00
58.10
58.30
58.20
58.74
58.64


Al2O3
13.43
13.43
13.33
13.33
13.63
13.63
13.03
13.03
13.05
13.15


CaO
23.44
23.54
23.39
23.29
23.24
23.14
23.54
23.64
22.97
22.97


MgO
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.36
2.36


TiO2
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.49
0.49


Na2O
—
—
—
—
—
—
—
—
—
—


K2O
—
—
—
—
—
—
—
—
0.09
0.09


Li2O
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.91
0.91


Fe2O3
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.29
0.29


B2O3
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00


RO (CaO + MgO)
25.94
26.04
25.89
25.79
25.74
25.64
26.04
26.14
25.33
25.33


SiO2/CaO
2.47
2.45
2.49
2.51
2.50
2.51
2.48
2.46
2.56
2.55


SiO2/RO
2.24
2.22
2.25
2.26
2.25
2.27
2.24
2.23
2.32
2.32


SiO2/Al2O3
4.32
4.31
4.36
4.37
4.26
4.26
4.47
4.47
4.50
4.46


Al2O3/CaO
0.57
0.57
0.57
0.57
0.59
0.59
0.55
0.55
0.57
0.57


SiO2 + Al2O3
71.43
71.33
71.48
71.58
71.63
71.73
71.33
71.23
71.79
71.79


R2O + RO + B2O3
27.84
27.94
27.79
27.69
27.14
27.54
27.94
28.04
27.33
27.33


(Si + Al)/(R2O + RO + B)
2.57
2.55
2.57
2.59
2.64
2.60
2.55
2.54
2.63
2.63


SiO2 − RO
32.06
31.86
32.26
32.46
32.26
32.46
32.26
32.06
33.41
33.31


Al2O3/RO
0.51
0.52
0.51
0.52
0.53
0.53
0.50
0.50
0.52
0.52


Log3 FT, ° C.
1202
1203
1203
1202
1207
1212
1200
1201
1210
1209


Liquidus T, ° C.
1139
1137
1136
1145
1144
1146
1132
1137
1145
1151


Delta T, ° C.
63
66
67
57
63
66
68
64
65
58












Examples

















Components (wt %)
198*
199
200
201
202
203
204
205
206
207





SiO2
58.64
58.75
57.80
57.60
57.60
57.60
58.50
58.40
58.30
58.40


Al2O3
12.95
12.93
13.23
13.23
13.23
13.03
12.76
12.76
13.03
13.03


CaO
22.87
22.93
23.84
23.84
23.84
24.04
23.61
23.71
23.54
23.44


MgO
2.36
2.36
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50


TiO2
0.49
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50


Na2O
—
0.04
—
—
0.20
0.20
—
—
—
—


K2O
0.09
0.10
—
—
—
—
—
—
—
—


Li2O
0.91
0.90
0.90
0.90
0.70
0.70
0.90
0.90
0.90
0.90


Fe2O3
0.29
0.29
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23


B2O3
1.00
1.20
1.00
1.20
1.20
1.20
1.00
1.00
1.00
1.00


RO (CaO + MgO)
25.23
25.29
26.34
26.34
26.34
26.54
26.11
26.21
26.04
25.94


SiO2/CaO
2.56
2.56
2.42
2.42
2.42
2.40
2.48
2.46
2.48
2.49


SiO2/RO
2.32
2.32
2.19
2.19
2.19
2.17
2.24
2.23
2.24
2.25


SiO2/Al2O3
4.53
4.54
4.37
4.35
4.35
4.37
4.58
4.58
4.47
4.48


Al2O3/CaO
0.57
0.56
0.55
0.55
0.55
0.54
0.54
0.54
0.55
0.56


SiO2 + Al2O3
71.59
71.68
71.03
70.83
70.83
70.63
71.26
71.16
71.33
71.43


R2O + RO + B2O3
27.23
27.53
28.24
28.44
28.44
28.64
28.01
28.11
27.94
27.84


(Si + Al)/(R2O + RO + B)
2.63
2.60
2.51
2.49
2.49
2.47
2.54
2.53
2.55
2.57


SiO2 − RO
33.41
33.46
31.46
31.26
31.26
31.06
32.39
32.19
32.26
32.36


Al2O3/RO
0.51
0.51
0.50
0.50
0.50
0.49
0.49
0.49
0.50
0.51


Log3 FT, ° C.
1204
1210
1201
1200
1208
1201
1202
1203
1201
1208


Liquidus T, ° C.
1142
1127
1126
1125
1135
1145
1141
1145
1138
1137


Delta T, ° C.
62
83
75
75
73
56
61
58
63
71












Examples

















Components (wt %)
208
209
210
211
212
213
214
215
216
217





SiO2
58.15
58.25
58.70
58.00
57.60
58.61
58.61
58.00
58.40
58.40


Al2O3
13.33
13.33
12.75
13.03
13.03
12.16
12.16
13.23
13.36
13.03


CaO
23.39
23.29
23.50
23.84
24.04
23.50
23.50
23.64
23.11
23.44


MgO
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50


TiO2
0.50
0.50
0.50
0.50
0.50
1.10
1.10
0.50
0.50
0.50


Na2O
—
—
0.60
—
—
—
0.45
—
—
—


K2O
—
—
—
—
—
—
—
—
—
—


Li2O
0.90
0.90
0.60
0.90
0.90
0.90
0.45
0.90
0.90
0.90


Fe2O3
0.25
0.25
0.25
0.23
0.23
0.23
0.23
0.23
0.23
0.23


B2O3
1.00
1.00
0.60
1.00
1.20
1.00
1.00
1.00
1.00
1.00


RO (CaO + MgO)
25.89
25.79
26.00
26.34
26.54
26.00
26.00
26.14
25.61
25.94


SiO2/CaO
2.49
2.50
2.50
2.43
2.40
2.49
2.49
2.45
2.52
2.49


SiO2/RO
2.25
2.26
2.26
2.20
2.17
2.25
2.25
2.22
2.28
2.25


SiO2/Al2O3
4.36
4.37
4.60
4.45
4.42
4.82
4.82
4.38
4.37
4.48


Al2O3/CaO
0.57
0.57
0.54
0.55
0.54
0.52
0.52
0.56
0.58
0.56


SiO2 + Al2O3
71.48
71.58
71.45
71.03
70.63
70.77
70.77
71.23
71.76
71.43


R2O + RO + B2O3
27.79
27.69
27.80
28.24
28.64
27.90
27.90
28.04
27.51
27.84


(Si + Al)/(R2O + RO + B)
2.57
2.59
2.57
2.52
2.47
2.54
2.54
2.54
2.61
2.57


SiO2 − RO
32.26
32.46
32.70
31.66
31.06
32.61
32.61
31.86
32.79
32.46


Al2O3/RO
0.51
0.52
0.49
0.49
0.49
0.47
0.47
0.51
0.52
0.50


Log3 FT, ° C.
1197
1200
1216
1202
1194
1201
1227
1201
1204
1201


Liquidus T, ° C.
1130
1134
1160
1137
1142
1142
1159
1135
1133
1136


Delta T, ° C.
67
66
56
65
52
59
68
66
71
65












Examples

















Components (wt %)
218
219
220
221
222
223
224
225
226
227





SiO2
58.50
58.60
58.00
58.10
58.10
58.70
58.70
58.70
58.61
58.40


Al2O3
13.03
13.03
13.63
13.23
13.43
12.75
12.35
12.35
12.16
12.76


CaO
23.34
23.24
23.24
23.54
23.34
23.50
23.50
23.50
23.50
23.71


MgO
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50


TiO2
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
1.10
0.50


Na2O
—
—
—
—
—
0.30
0.60
0.30
—
—


K2O
—
—
—
—
—
—
—
—
—
—


Li2O
0.90
0.90
0.90
0.90
0.90
0.90
0.60
0.90
0.90
0.90


Fe2O3
0.23
0.23
0.23
0.23
0.23
0.25
0.25
0.25
0.23
0.23


B2O3
1.00
1.00
1.00
1.00
1.00
0.60
1.00
1.00
1.00
1.00


RO (CaO + MgO)
25.84
25.74
25.74
26.04
25.84
26.00
26.00
26.00
26.00
26.21


SiO2/CaO
2.51
2.51
2.50
2.47
2.49
2.50
2.50
2.50
2.49
2.46


SiO2/RO
2.26
2.28
2.25
2.23
2.25
2.26
2.26
2.26
2.25
2.23


SiO2/Al2O3
4.49
4.50
4.26
4.39
4.33
4.60
4.75
4.75
4.82
4.58


Al2O3/CaO
0.56
0.56
0.59
0.56
0.58
0.54
0.53
0.53
0.52
0.54


SiO2 + Al2O3
71.53
71.63
71.63
71.33
71.53
71.45
71.05
71.05
70.77
71.16


R2O + RO + B2O3
27.74
27.64
27.64
27.94
27.74
27.80
28.20
28.20
27.90
28.11


(Si + Al)/(R2O + RO + B)
2.58
2.59
2.59
2.55
2.58
2.57
2.52
2.52
2.54
2.53


SiO2 − RO
32.66
32.86
32.26
32.06
32.26
32.70
32.70
32.70
32.61
32.19


Al2O3/RO
0.50
0.51
0.53
0.51
0.52
0.49
0.48
0.48
0.47
0.49


Log3 FT, ° C.
1204
1204
1206
1199
1204
1204
1207
1202
1194
1194


Liquidus T, ° C.
1133
1135
1136
1133
1134
1153
1157
1149
1141
1144


Delta T, ° C.
71
69
70
63
70
51
50
53
53
50












Examples

















Components (wt %)
228
229
230
231
232
233
234
235
236
237





SiO2
58.80
57.60
58.11
58.91
58.11
58.30
58.20
58.10
58.70
58.70


Al2O3
12.46
13.03
13.36
12.16
13.36
13.03
13.03
13.03
13.35
13.35


CaO
23.61
24.04
23.40
23.80
23.40
23.54
23.64
23.74
23.50
23.50


MgO
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50


TiO2
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50
0.50


Na2O
—
0.10
—
—
—
—
—
—
—
—


K2O
—
—
—
—
—
—
—
—
—
—


Li2O
0.90
0.80
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.60


Fe2O3
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.25
0.25


B2O3
1.00
1.20
1.00
1.00
1.00
1.00
1.00
1.00
0.30
0.60


RO (CaO + MgO)
26.11
26.54
25.90
26.30
25.90
26.04
26.14
26.24
26.00
26.00


SiO2/CaO
2.49
2.40
2.48
2.48
2.48
2.48
2.46
2.45
2.50
2.50


SiO2/RO
2.25
2.17
2.24
2.24
2.24
2.24
2.23
2.21
2.26
2.26


SiO2/Al2O3
4.70
4.42
4.35
4.84
4.35
4.47
4.47
4.46
4.40
4.40


Al2O3/CaO
0.53
0.54
0.57
0.51
0.57
0.55
0.55
0.55
0.57
0.57


SiO2 + Al2O3
71.26
70.63
71.47
71.07
71.47
71.23
71.23
71.13
72.05
72.05


R2O + RO + B2O3
28.01
28.64
27.80
28.20
27.80
27.94
28.04
28.14
27.20
27.20


(Si + Al)/(R2O + RO + B)
2.54
2.47
2.57
2.52
2.57
2.55
2.54
2.53
2.65
2.65


SiO2 − RO
32.69
31.06
32.21
32.61
32.21
32.26
32.06
31.86
32.70
32.70


Al2O3/RO
0.48
0.49
0.52
0.46
0.52
0.50
0.50
0.50
0.51
0.51


Log3 FT, ° C.
1195
1196
1229
1216
1213
1202
1202
1205
1207
1224


Liquidus T, ° C.
1145
1145
1155
1148
1142
1136
1136
1137
1144
1145


Delta T, ° C.
50
51
133
123
126
120
119
122
114
142












Examples

















Components (wt %)
238
239
240
241
242
243
244
245
246
247





SiO2
58.11
58.20
59.53
59.61
59.11
59.11
59.16
59.21
59.11
59.36


Al2O3
13.36
13.23
12.25
12.16
12.16
12.16
12.16
12.16
12.16
12.41


CaO
23.40
23.44
23.17
23.50
23.00
23.00
23.20
23.40
23.50
23.60


MgO
2.50
2.50
2.52
2.50
2.50
2.50
2.25
2.00
2.00
2.00


TiO2
0.50
0.50
0.50
1.10
1.10
1.10
1.10
1.10
1.10
0.50


Na2O
—
—
—
—
—
—
—
—
—
—


K2O
—
—
—
—
—
—
—
—
—
—


Li2O
0.90
0.90
0.80
0.45
0.90
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23


B2O3
1.00
1.00
1.00
0.45
1.00
1.00
1.00
1.00
1.00
1.00


RO (CaO + MgO)
25.90
25.94
25.69
26.00
25.50
25.50
25.45
25.40
25.50
25.60


SiO2/CaO
2.48
2.48
2.57
2.54
2.57
2.57
2.55
2.53
2.51
2.51


SiO2/RO
2.24
2.24
2.32
2.29
2.32
2.32
2.32
2.33
2.32
2.32


SiO2/Al2O3
4.35
4.40
4.86
4.90
4.86
4.86
4.87
4.87
4.87
4.78


Al2O3/CaO
0.57
0.56
0.53
0.52
0.53
0.53
0.52
0.52
0.52
0.53


SiO2 + Al2O3
71.47
71.43
71.78
71.77
71.27
71.27
71.32
71.37
71.27
71.77


R2O + RO + B2O3
27.80
27.84
27.49
26.90
27.40
27.40
27.35
27.30
27.40
27.50


(Si + Al)/(R2O + RO + B)
2.57
2.57
2.61
2.67
2.60
2.60
2.61
2.61
2.60
2.61


SiO2 − RO
32.21
32.26
33.84
33.61
33.61
33.61
33.71
33.81
33.61
33.76


Al2O3/RO
0.52
0.51
0.48
0.47
0.48
0.48
0.48
0.48
0.48
0.53


Log3 FT, ° C.
1212
1204
1214
1230
1205
1216
1218
1213
1209
1216


Liquidus T, ° C.
1135
1135
1143
1155
1142
1143
1147
1153
1153
1153


Delta T, ° C.
139
124
71
75
63
73
71
60
56
63












Examples

















Component (wt %)
248
249
250
251
252
253
254
255
256
257





SiO2
59.31
59.36
59.41
59.11
59.16
59.21
59.16
59.11
59.01
59.21


Al2O3
12.56
12.51
12.46
12.16
12.16
12.16
12.26
12.26
12.36
12.16


CaO
23.50
23.50
23.50
23.00
23.20
23.40
23.45
23.50
23.50
23.50


MgO
2.00
2.00
2.00
2.50
2.25
2.00
2.50
2.50
2.50
2.50


TiO2
0.50
0.50
0.50
1.10
1.10
1.10
0.50
0.50
0.50
0.50


Na2O
—
—
—
—
—
—
—
—
—
—


K2O
—
—
—
—
—
—
—
—
—
—


Li2O
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90
0.90


Fe2O3
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23
0.23


B2O3
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00


RO (CaO + MgO)
25.50
25.50
25.50
25.50
25.45
25.40
25.95
26.00
26.00
26.00


SiO2/CaO
2.52
2.53
2.53
2.57
2.55
2.53
2.52
2.52
2.51
2.52


SiO2/RO
2.33
2.33
2.33
2.32
2.32
2.33
2.28
2.27
2.27
2.28


SiO2/Al2O3
4.72
4.75
4.77
4.86
4.87
4.87
4.83
4.82
4.77
4.87


Al2O3/CaO
0.53
0.53
0.53
0.53
0.52
0.52
0.52
0.52
0.53
0.52


SiO2 + Al2O3
71.87
71.87
71.87
71.27
71.32
71.37
71.42
71.37
71.37
71.37


R2O + RO + B2O3
27.40
27.40
27.40
27.40
27.35
27.30
27.85
27.90
27.90
27.90


(Si + Al)/(R2O + RO + B)
2.62
2.62
2.62
2.60
2.61
2.61
2.56
2.56
2.56
2.56


SiO2 − RO
33.81
33.86
33.91
33.61
33.71
33.81
33.21
33.11
33.01
33.21


Al2O3/RO
0.49
0.49
0.49
0.48
0.48
0.48
0.47
0.47
0.48
0.47


Log3 FT, ° C.
1220
1220
1220
1216
1214
1220
1209
1210
1210
1201


Liquidus T, ° C.
1153
1158
1155
1144
1147
1158
1150
1152
1152
1143


Delta T, ° C.
67
62
65
72
67
62
59
58
58
58












Examples

















Components (wt %)
258
259
260
261
262
263
264
265
266
267





SiO2
58.75
58.75
58.10
58.70
59.11
59.31
59.21
54.60
56.75
57.85


Al2O3
12.93
12.93
13.63
13.35
12.16
12.26
12.26
13.35
13.20
12.45


CaO
22.93
22.93
23.14
23.50
23.50
22.30
23.40
24.55
23.95
24.05


MgO
2.36
2.36
2.50
2.50
2.00
2.50
2.50
2.55
2.55
2.55


TiO2
0.50
0.50
0.50
0.50
1.10
0.50
0.50
0.35
1.10
0.55


Na2O
0.14
0.24
—
—
—
—
—
0.15
0.60
0.60


K2O
0.10
0.10
—
—
—
—
—
0.55
—
—


Li2O
0.80
0.70
0.90
0.30
0.90
0.90
0.90
0.30
0.30
0.30


Fe2O3
0.29
0.29
0.23
0.25
0.23
0.23
0.23
0.28
0.25
0.35


B2O3
1.20
1.20
1.00
0.90
1.00
1.00
1.00
3.00
1.40
1.30


F
—
—
—
—
—
—
—
0.20
—
—


SrO
—
—
—
—
—
—
—
0.12
—
—


RO (CaO + MgO)
25.29
25.29
25.64
26.00
25.50
24.80
25.90
27.10
26.50
26.60


SiO2/CaO
2.56
2.56
2.51
2.50
2.52
2.66
2.53
2.22
2.37
2.39


SiO2/RO
2.32
2.32
2.27
2.26
2.32
2.39
2.29
2.01
2.14
2.35


SiO2/Al2O3
4.54
4.54
4.26
4.40
4.86
4.84
4.83
4.09
4.30
4.65


Al2O3/CaO
0.56
0.56
0.59
0.57
0.52
0.55
0.52
0.54
0.55
0.52


SiO2 + Al2O3
71.68
71.68
71.73
72.05
71.27
71.57
71.47
67.95
69.95
71.30


R2O + RO + B2O3
27.53
27.53
27.54
27.20
27.40
26.70
27.80
31.10
28.80
28.80


(Si + Al)/(R2O + RO + B)
2.60
2.60
2.60
2.65
2.60
2.68
2.57
2.18
2.43
2.48


SiO2 − RO
33.46
33.46
32.46
32.70
33.61
34.51
33.31
27.50
30.25
31.25


Al2O3/RO
0.51
0.51
0.53
0.51
0.48
0.49
0.47
0.49
0.50
0.47


Log3 FT, ° C.
1211
1218
1204
1239
1215
1209
1210
1187
1206
1208


Liquidus T, ° C.
1127
1129
1115
1143
1155
1148
1156
1133
1152
1154


Delta T, ° C.
84
89
89
96
60
61
54
54
54
54





*compositions include 0.05 wt % SrO and 0.08 wt % SO3













TABLE 19







Misc. Glasses









Examples












Components (wt %)
268
269
270
271
272















SiO2
57.82
58.70
58.70
57.72
58.61


Al2O3
11.80
13.35
13.35
11.80
12.16


CaO
22.80
23.50
23.50
22.80
23.50


MgO
2.43
2.50
2.50
2.52
2.50


TiO2
1.07
0.50
0.50
1.07
1.10


Na2O
0.87
—
0.90
0.87
—


Li2O
—
0.30
0.30
—
0.30


ZnO
—
—
—
—
0.30


MnO
3.00
—
—
—
0.30


MnO2
—
—
—
3.00
—


Fe2O3
0.22
0.25
0.25
0.22
0.23


B2O3
—
0.90
—
—
1.00


RO
25.23
26.00
26.00
25.32
26.00


SiO2/CaO
2.54
2.50
2.50
2.53
2.49


SiO2/RO
2.29
2.26
2.26
2.28
2.25


SiO2/Al2O3
4.90
4.40
4.40
4.89
4.82


Al2O3/CaO
0.52
0.57
0.57
0.52
0.52


SiO2 + Al2O3
69.62
72.05
72.05
69.52
70.77


RO2 + RO + B2O3
26.10
27.20
26.30
26.19
27.30


(Si + Al)/
2.67
2.65
2.74
2.65
2.59


(R2O + RO + B)


SiO2 − RO
32.59
32.70
32.70
32.40
32.61


Al2O3/RO
0.47
0.51
0.51
0.47
0.47


Log3 FT, ° C.
1219
1239
1241
1222
1223


Liquidus T, ° C.
1163
1143
1165
1161
1139


Delta T, ° C.
52
96
76
61
94
















TABLE 20





Production Glasses

















Examples














Components (wt %)
273
274
275
276
277
278
279





SiO2
57.07
57.21
56.94
56.68
56.71
56.53
55.97


Al2O3
12.69
12.77
12.72
12.68
12.95
12.84
12.68


CaO
23.91
24.15
24.00
24.11
24.56
24.42
24.00


MgO
2.53
2.57
2.56
2.58
2.44
2.42
2.45


TiO2
1.09
1.12
1.12
1.09
1.07
1.07
1.05


Na2O
0.89
0.90
0.87
0.90
0.92
0.92
0.88


K2O
0.060
0.050
0.050
0.060
0.070
0.060
0.060


Fe2O3
0.255
0.271
0.255
0.263
0.278
0.267
0.265


B2O3
1.37
1.36
1.42
1.40
1.54
1.70
1.36


SO3
0.029
0.032
0.032
0.031
0.028
0.024
0.025


SrO
0.040
0.040
0.050
0.050
0.050
0.050
0.050


Cr2O3
0.002
0.002
0.002
0.002
0.009
0.008
0.007


RO
26.44
26.72
26.56
26.69
27.00
26.84
26.45


SiO2/CaO
2.39
2.37
2.37
2.35
2.31
2.31
2.33


SiO2/RO
2.16
2.14
2.14
2.12
2.10
2.11
2.12


SiO2/Al2O3
4.50
4.48
4.48
4.47
4.38
4.40
4.41


Al2O3/CaO
0.53
0.53
0.53
0.53
0.53
0.53
0.53


SiO2 + Al2O3
69.76
69.98
69.66
69.36
69.66
69.37
68.65


RO2 + RO + B2O3
28.96
29.25
29.11
29.25
29.74
29.73
28.96


(Si + Al)/(R2O + RO + B)
2.41
2.39
2.39
2.37
2.34
2.33
2.37


SiO2 − RO
30.63
30.49
30.38
29.99
29.71
29.69
29.52


Al2O3/RO
0.48
0.48
0.48
0.48
0.48
0.48
0.48


Log3 FT, ° C.
1214

1217

1203
1212
1212


Liquidus T, ° C.
1147

1134

1145
1147
1134


Delta T, ° C.
67

83

58
65
76













Examples














Components (wt %)
280
281
282
283
284
285





SiO2
56.70
56.66
56.63
56.54
56.43
56.61


Al2O3
12.91
12.86
12.85
12.79
12.75
12.83


CaO
24.61
24.53
24.69
24.53
24.44
25.24


MgO
2.54
2.56
2.60
2.54
2.54
2.55


TiO2
1.10
1.09
0.94
0.94
1.09
1.20


Na2O
0.91
0.90
0.93
0.90
0.90
0.92


K2O
0.060
0.060
0.070
0.070
0.050
0.050


Fe2O3
0.260
0.265
0.267
0.268
0.270
0.279


B2O3
1.32
1.15
1.34
1.27
1.24
1.29


SO3
0.018
0.020
0.018
0.016
0.014
0.016


SrO
0.040
0.040
0.040
0.040
0.040
0.040


Cr2O3
0.004
0.004
0.003
0.002
0.008
0.004


RO
27.15
27.09
27.29
27.07
26.98
27.79


SiO2/CaO
2.30
2.31
2.29
2.30
2.31
2.24


SiO2/RO
2.09
2.09
2.08
2.09
2.09
2.04


SiO2/Al2O3
4.39
4.41
4.41
4.42
4.43
4.41


Al2O3/CaO
0.52
0.52
0.52
0.52
0.52
0.51


SiO2 + Al2O3
69.61
69.52
69.48
69.33
69.18
69.44


RO2 + RO + B2O3
29.64
29.41
29.83
29.51
29.39
30.28


(Si + Al)/(R2O + RO + B)
2.35
2.36
2.33
2.35
2.35
2.29


SiO2 − RO
29.55
29.57
29.34
29.47
29.45
28.82


Al2O3/RO
0.48
0.47
0.47
0.47
0.47
0.46


Log3 FT, ° C.

1213
1214


Liquidus T, ° C.

1149
1158


Delta T, ° C.

64
55
















TABLE 21







Summary Sheet














Type 1 Glasses
Type 2 Glasses
Type 3 Glasses
Type 4 Glasses
Type 5 Glasses
Type 6 Glasses




















Low
High
Low
High
Low
High
Low
High
Low
High
Low
High























RO (CaO + MgO)
26.30
27.05
24.80
27.56
24.01
26.70
25.40
26.60
25.80
25.90
25.29
26.60


SiO2/CaO
2.35
2.47
2.20
2.55
2.39
2.71
2.41
2.54
2.62
2.62
2.22
2.66


SiO2/RO
2.13
2.23
1.96
2.29
2.16
2.52
2.18
2.29
2.28
2.28
2.01
2.39


SiO2/Al2O3
4.25
4.84
3.79
4.76
4.30
4.99
4.26
4.90
4.92
4.93
4.09
4.90


Al2O3/CaO
0.51
0.58
0.51
0.59
0.50
0.59
0.50
0.59
0.53
0.53
0.51
0.59


SiO2 + Al2O3
70.85
71.86
66.10
70.95
71.05
73.67
71.03
71.73
70.60
71.00
67.95
72.05


R2O + RO + B2O3
27.20
27.95
28.15
32.79
25.15
27.60
26.30
27.50
26.70
26.80
26.70
31.10


(Si + Al)/(R2O + RO + B)
2.55
2.64
2.02
2.67
2.30
2.96
2.60
2.71
2.64
2.65
2.18
2.68


SiO2 − RO
30.55
32.55
26.50
32.55
30.95
36.56
31.15
33.61
32.90
33.10
27.50
33.91


Al2O3/RO
0.46
0.52
0.46
0.56
0.47
0.53
0.47
0.53
0.46
0.46
0.46
0.53
















TABLE 22







Summary Sheet















Types 1 &, 3–5, Glasses
Types 2 & 6 Glasses
Production Glasses



Types 1 & 2 Glasses
Types 3–6 Glasses
(boron-free)
(contains boron)
(contains boron)


















Low
High
Low
High
Low
High
Low
High
Low
High





















RO (CaO + MgO)
24.80
27.56
24.01
26.70
24.01
26.90
24.80
27.56
26.44
27.79


SiO2/CaO
2.20
2.55
2.39
2.71
2.36
2.73
2.20
2.66
2.24
2.37


SiO2/RO
1.96
2.29
2.16
2.52
2.14
2.52
1.96
2.39
2.08
2.16


SiO2/Al2O3
3.79
4.84
4.26
4.99
4.26
4.99
3.79
4.90
4.38
4.50


Al2O3/CaO
0.51
0.59
0.50
0.59
0.50
0.59
0.51
0.59
0.51
0.53


SiO2 + Al2O3
66.10
71.45
70.60
73.67
70.85
73.67
66.10
72.05
68.65
69.98


R2O + RO + B2O3
27.20
32.79
25.15
28.64
25.15
27.80
26.90
32.79
28.96
30.28


(Si + Al)/(R2O + RO + B)
2.02
2.67
2.30
2.96
2.30
2.96
2.02
2.68
2.29
2.41


SiO2 − RO
26.50
32.55
30.95
36.56
30.55
36.56
26.50
33.91
28.82
30.63


Al2O3/RO
0.46
0.56
0.46
0.53
0.46
0.53
0.46
0.56
0.46
0.48

## Claims

1. A glass composition comprising:
















SiO2
57 to 58.2 percent by weight;



Al2O3
12 to 13.7 percent by weight;



CaO
23.5 to 24.5 percent by weight;



MgO
2 to 3 percent by weight;



TiO2
0.5 to 2 percent by weight;



Na2O
0 to 1 percent by weight;



Li2O
0 to less than 0.1 percent by weight;



Na2O + K2O + Li2O
0 to 1 percent by weight;



Fe2O3
0.05 to 0.4 percent by weight;



B2O3
0 to 0.05 percent by weight;



fluorine
no greater than 0.30 percent by weight;










wherein the glass composition has a log 3 forming temperature no greater than 1240° C., and the difference between the log 3 forming temperature and the liquidus temperature is at least 50° C.

2. A glass composition comprising:
















SiO2
57 to less than 59 percent by weight;



Al2O3
12 to 14 percent by weight;



CaO
23 to 25 percent by weight;



MgO
1 to 3 percent by weight;



TiO2
0 to 2 percent by weight;



Na2O
0 to 1.25 percent by weight;



Li2O
0 to less than 0.1 percent by weight;



Na2O + K2O + Li2O
0 to 1.25 percent by weight;



Fe2O3
up to 0.5 percent by weight;



B2O3
0 to 0.05 percent by weight;



fluorine
no greater than 0.30 percent by weight;










wherein the glass composition has a log 3 forming temperature no greater than 1240° C., and the difference between the log 3 forming temperature and the liquidus temperature is at least 50° C.

3. The glass composition according to claim 2, wherein the TiO2 content is 0.5 to 1.5 percent by weight.

4. The glass composition according to claim 2, wherein the glass composition is essentially free of B2O3.

5. The glass composition according to claim 2, wherein the Fe2O3 content is 0.1 to 0.4 percent by weight.

6. The glass composition according to claim 2, wherein the ratio of SiO2 to (CaO+MgO) is no greater than 2.55.

7. The glass composition according to claim 2, wherein the ratio of SiO2 to (CaO+MgO) is from 1.9 to 2.4.

8. The glass composition according to claim 2, wherein (CaO+MgO) is from 26 to 28 percent by weight.

9. The glass composition according to claim 2, wherein the composition is essentially free of Li2O.

10. The glass composition according to claim 2, wherein (Na2O+K2O+Li2O) is no greater about 1.03 percent by weight.

11. The glass composition according to claim 2, wherein (Na2O+K2O+Li2O) is no greater than 1 percent by weight.

12. The glass composition according to claim 2, wherein the difference between the log 3 forming temperature and the liquidus temperature is at least 60° C.

13. The glass composition according to claim 1 wherein the SiO2 is less than 58 percent by weight.