Patent Description:
In recent years, there has been a growing desire for environmentally friendly coatings aimed at reducing or mitigating impacts on human beings and ecology and on the global environment. A need thus exists for coatings which do not contain specific volatile organic compounds (VOCs) such as toluene, xylene and ethylbenzene that generate photochemical smog and are in other ways deleterious to the environment and that are also a cause of sick building syndrome.

In general, organosiloxane-containing coatings often use solvents such as toluene and xylene (TX solvents) because of their high solvency. However, TX solvents have a large impact on the environment and, because of their high volatility, also tend to cause cracks and uneven coating to arise in the applied coat.

The environmentally friendly solvent ethylene glycol, owing to its low impact on humans and nature and the fact that it is easy to handle, is a TX-free solvent whose usage lately has been trending upwardly. Ethylene glycol also has a high boiling point, as a result of which the adverse effect on the human body due to exposure to solvent gases is limited. In addition, ethylene glycol has a low volatility and so is very easy to work with, and cracks and uneven coating do not readily arise in the applied coat, making it suitable for use as a solvent in coatings.

Separately, with regard to organopolysiloxanes that have polymerizable functional groups, from the standpoint of hardness and flexibility, organopolysiloxanes having divalent or trivalent siloxane bonds on the skeleton are often used as the chief raw material in coatings. In particular, trivalent siloxane bonds are essential in terms of hardness and adhesion to the underlying material.

The condition at the surface of the applied coat differs according to the molecular weight of the organopolysiloxane. When the molecular weight is small, the ratio of the number of polymerizable functional groups is large, which becomes a cause of crack formation over time. When the molecular weight is large, the ratio of the number of polymerizable functional groups is small, leading to poor adhesion and becoming a cause of low hardness and low scuff resistance.

<CIT> discloses examples of low-VOC aqueous latex coatings in which an oligomeric ethylene glycol derivative is used as the solvent. The oligomeric ethylene glycol functions both as a film-forming solvent and a thaw stabilizer. Coats having an excellent scuff resistance can reportedly be obtained from such coatings. <CIT> discloses that a good scuff resistance and adhesion can be obtained in silicone resin composition films for which the ratio of condensation-curable functional groups falls in a specific range. <CIT> discloses a composition for film formation comprising an organopolysiloxane compound and a propylene glycol monoalkyl ether solvent, such as propylene glycol monopropyl ether and propylene glycol monomethyl ether. <CIT> discloses a composition comprising a thermal crosslinking accelerator which is a polysiloxane compound and propylene glycol ethyl ether as a solvent in an amount of more than <NUM> wt% of the composition. <CIT> discloses a thermosetting composition comprising a solvent and at least one siloxane polymer, wherein the solvent is diethylene glycol methyl ethyl ether. <CIT> discloses a composition for forming an inverted pattern containing a polysiloxane and a solvent in an amount of more than <NUM> wt% of the composition, wherein the solvent contains polyhydric alcohol, such as propylene glycol monoethyl ether. <CIT> discloses a composition for film formation containing a polysiloxane and an alcohol solvent in an amount of more than <NUM> wt% of the composition, wherein the solvent is propylene glycol monopropyl ether. <CIT> discloses a liquid coating composition for the formation of a siliceous coating film, which is a uniform solution comprising a polysiloxane and an organic solvent, such as ethyleneglycol dimethyl ether, ethyleneglycol diethyl ether or propyleneglycol dimethyl ether.

In view of the above circumstances, the objects of the invention are to provide a composition which contains a TX-free environmentally friendly solvent (that is dipropylene glycol dimethyl ether) and an organopolysiloxane compound, a method for preparing such a composition, a coating material that has excellent coating properties and is able to give a smooth cured film having a good crack resistance and adhesion, and a coated article.

The inventors have conducted extensive investigations aimed at achieving these objects and have found as a result that the above objects can be achieved in a composition which includes, together with an organopolysiloxane having condensable functional groups, a glycol ether solvent (that is dipropylene glycol dimethyl ether). This discovery ultimately led to the present invention.

Accordingly, the present invention provides a composition containing (A) an organopolysiloxane compound having a structure of average formula (I) and a specific amount of (B) dipropylene glycol dimethyl ether, a method for preparing such a composition, a coating material and a coated article thereof, as defined in the claims.

The inventive composition contains an organopolysiloxane having polymerizable functional groups and a glycol ether solvent (that is dipropylene glycol dimethyl ether). As a result, its impact on humans and ecology and on the global environment is reduced or mitigated, in addition to which cracks and uneven coating do not readily arise in cured films (coats) thereof, making the composition useful as an environmentally friendly coating.

Component (A) of the invention is an organopolysiloxane compound having a structure of average formula (I) below.

(SiO<NUM>/<NUM>)a(R<NUM>SiO<NUM>/<NUM>)b(R<NUM><NUM>SiO<NUM>/<NUM>)c(R<NUM><NUM>SiO<NUM>/<NUM>)d(R<NUM>O<NUM>/<NUM>)e     (I).

In formula (I), each R<NUM> is independently a hydrogen atom or an alkyl group, aralkyl group or aryl group of <NUM> to <NUM> carbon atoms which may be substituted with halogen atoms; R<NUM> is a hydrogen atom, methyl group, ethyl group, n-propyl group or i-propyl group; "a", "b", "c" and "d" are respectively numbers which satisfy the conditions <NUM> ≤ a < <NUM>, <NUM> < b ≤ <NUM>, <NUM> ≤ c < <NUM>, <NUM> ≤ d < <NUM> and a+b+c+d = <NUM>; and "e" is a number which satisfies the condition <NUM> < e ≤ <NUM>.

The subscript "a" is a number which satisfies the condition <NUM> ≤ a < <NUM>. From the standpoint of the crack suppressing effects in the resulting cured product (cured film), it is preferable for <NUM> ≤ a ≤ <NUM>.

The subscript "b" is a number which satisfies the condition <NUM> < b ≤ <NUM>. From the standpoint of the scuff resistance of the resulting cured product (cured film), it is preferable for <NUM> ≤ b ≤ <NUM>.

The subscript "c" is a number which satisfies the condition <NUM> ≤ c < <NUM>. From the standpoint of the curability of the composition and the hardness of the resulting cured product (cured film), it is preferable for <NUM> ≤ c ≤ <NUM>.

The subscript "d" is a number which satisfies the condition <NUM> ≤ d < <NUM>. From the standpoint of the curability of the composition and the hardness of the resulting cured product (cured film), it is preferable for <NUM> ≤ d ≤ <NUM>.

The subscript "e" is a number which satisfies the condition <NUM> < e ≤ <NUM>. To be effective in suppressing condensation reactions by the condensable functional groups, and also from the standpoint of the cracking resistance, water resistance and weather resistance of the resulting cured product, "e" is preferably a number that satisfies the condition <NUM> < e ≤ <NUM>.

The organopolysiloxane compound (A) of the invention may be a single organopolysiloxane compound or may be a mixture of a plurality of different organopolysiloxane compounds.

The weight-average molecular weight of the organopolysiloxane compound (A) of the invention is not particularly limited, although the polystyrene-equivalent weight-average molecular weight as determined by gel permeation chromatography (GPC) is preferably from <NUM>,<NUM> to <NUM>,<NUM>, and more preferably from <NUM>,<NUM> to <NUM>,<NUM>. At a weight-average molecular weight below <NUM>,<NUM>, condensation may not fully proceed and the shelf stability of the organopolysiloxane compound may decrease. Also, the condensation reaction may arise over time, and so there is a possibility that the cracking resistance may not be very good. At a high molecular weight greater than <NUM>,<NUM>, the organopolysiloxane compound becomes insoluble in solvents and defects such as hard spots and uneven coating may arise.

The organopolysiloxane compound of the invention preferably has, excluding the solvent, etc., a nonvolatiles content of at least <NUM> wt%. A higher level of volatiles may worsen the appearance due to void formation during curing of the composition or may cause a decrease in the mechanical properties.

The content of component (A) (pure component (A) including no solvent) is from <NUM> to <NUM> wt%, preferably from <NUM> to <NUM> wt%, and more preferably from <NUM> to <NUM> wt%, of the composition. When the component (A) content (as nonvolatile matter) is less than <NUM> wt%, a cured product with a sufficient thickness after coating may not be obtainable. When it exceeds <NUM> wt%, the composition may not give a smooth cured product.

The organopolysiloxane compound (A) of the invention can be produced by a general method for producing organopolysiloxanes. For example, the organopolysiloxane compound of the invention can be obtained by the hydrolytic condensation of a silane compound having hydrolysable groups. The hydrolysable group-containing silane compound and the amount thereof, the solvent, the degree of hydrolysis (e.g. temperature, time, type of catalyst) and the like are suitably adjusted so as to produce an organopolysiloxane compound having a structure of average formula (I) above.

The starting material used to produce the organopolysiloxane may be any hydrolysable group-containing silane compound in which the type of hydrolysable group is a chloro or alkoxy group and the number of hydrolysable groups is one, two, three or four, and which has organic substituents that satisfy the above conditions. Specific examples of silane compounds that may be used include tetrachlorosilane, tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, methyltrichlorosilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltributoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldiisopropoxysilane, trimethylchlorosilane, trimethylmethoxysilane, trimethylethoxysilane, trimethylisopropoxysilane, ethyltrichlorosilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrichlorosilane, propyltrimethoxysilane, propyltriethoxysilane, butyltrichlorosilane, butyltrimethoxysilane, butyltriethoxysilane, hexyltrichlorosilane, hexyltrimethoxysilane, hexyltriethoxysilane, phenyltrichlorosilane, phenyltrimethoxysilane, phenyltriethoxysilane, cyclohexyltrichlorosilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, propylmethyldichlorosilane, propylmethyldimethoxysilane, propylmethyldiethoxysilane, hexylmethyldichlorosilane, hexylmethyldimethoxysilane, hexylmethyldiethoxysilane, phenylmethyldichlorosilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, diphenyldichlorosilane, diphenyldimethoxysilane, diphenyldiethoxysilane, dimethylphenylchlorosilane, dimethylphenylmethoxysilane, dimethylphenylethoxysilane, and partial hydrolysates of these. However, the organosilicon compounds that may be used are not limited to these.

In terms of handleability, ease of distilling off by-products and availability of the starting material, the use of methoxysilane or ethoxysilane is more preferred. One of these silane compounds may be used alone or a mixture of two or more may be used together.

A hydrolysis catalyst may be used when carrying out hydrolysis. A known catalyst may be used as the hydrolysis catalyst, with the use of an aqueous solution thereof that has an acidity of pH <NUM> to <NUM> being desirable. In particular, acidic hydrogen halides, sulfonic acids, carboxylic acids, acidic or weakly acidic inorganic salts, and solid acids such as ion-exchange resins are preferred. Examples include hydrogen fluoride, hydrochloric acid, nitric acid, sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid, formic acid, acetic acid, maleic acid, benzoic acid, lactic acid, phosphoric acid, and cation-exchange resins having sulfonic acid or carboxylic acid groups on the surface.

The amount of hydrolysis catalyst used is not particularly limited. However, to have the reaction proceed quickly and also taking into account the ease of removing the catalyst after the reaction, an amount within the range of <NUM> to <NUM> mole per mole of hydrolysable silane is preferred.

The ratio between the amount of hydrolysable silane and the amount of water required for the hydrolytic condensation reaction is not particularly limited. However, to prevent catalyst deactivation and have the reaction proceed to a sufficient degree, and also taking into account the ease of removing water following the reaction, a ratio of from <NUM> to <NUM> moles of water per mole of hydrolysable silane is preferred.

The hydrolytic condensation reaction temperature is not particularly limited. However, to increase the rate of conversion and also prevent degradation of the organic functional groups on the hydrolysable silane, a temperature of between -<NUM> and <NUM> is preferred.

At the time of the hydrolytic condensation reaction, the subsequently described solvent (B) may be used or an organic solvent other than solvent (B) may be used. Examples of the organic solvent include methanol, ethanol, propanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, toluene and xylene. When an organic solvent other than solvent (B) has been used, it is preferable to replace it with a solvent (B) by treatment such as a stripping operation.

Following the hydrolytic condensation reaction, neutralization with an amount of synthetic hydrotalcite or the like sufficient for neutralization, followed by filtration, may be carried out.

Component (B) of the invention is dipropylene glycol dimethyl ether as a solvent.

The content of component (B) is <NUM> to <NUM> wt%, of the composition. At a component (B) content below <NUM> wt% of the composition, a smooth cured product might not be obtained.

It is preferable for the composition of the invention to include substantially no TX solvents. As used herein, "TX solvents" refers to aromatic hydrocarbon solvents such as toluene and xylene. Also, "to include substantially no TX solvents" means that the TX solvent content is <NUM> wt% or less of the composition. The TX solvent content is preferably <NUM> wt% or less, and may be <NUM> wt%.

Optional additives may be suitably included in the composition of the invention, within ranges that do not detract from the advantageous effects of the invention.

Specific examples of such additives include tackifiers such as non-reactive silicone oils, reactive silicone oils and silane coupling agents, antidegradants, rust inhibitors, colorants, surfactants, rheology modifiers, ultraviolet absorbers, infrared absorbers, fluorescent agents, abrasives, scents, loading materials, fillers, dyes and pigments, leveling agents, reactive diluents, non-reactive polymer resins, antioxidants, ultraviolet absorbers, light stabilizers, antifoaming agents, dispersants, antistatic agents and thixotropic agents. Each of these may be of one type used alone, or two or more types may be suitably combined and used in appropriate amounts.

The viscosity of the inventive composition is not particularly limited. However, for good molding and coating workability and to suppress the occurrence of streak-like unevenness, the viscosity at <NUM> as measured with a rotational viscometer is preferably not more than <NUM>,<NUM> mPa·s, and more preferably not more than <NUM>,<NUM> mPa·s. The lower limit, although not particularly defined, may be set to <NUM> mPa·s.

The inventive composition can be formed into a cured film by drying under room temperature and heating conditions. However, to accelerate the rate of cure or obtain excellent film properties, a curing catalyst such as a condensation curing catalyst may be added at the time that the composition is used, or a curing catalyst may additionally be included so as to give a curable composition.

The curing catalyst may be suitably selected from among known catalysts and used. Exemplary curing catalysts include organometallic compounds such as organotin compounds, organotitanium compounds, organozirconium compounds and organoaluminum compounds; inorganic acids such as hydrochloric acid and sulfuric acid; organic acids such as p-toluenesulfonic acid and various aliphatic or aromatic carboxylic acids; ammonia; inorganic bases such as sodium hydroxide; and organic bases such as tributylamine, <NUM>,<NUM>-diazabicyclo[<NUM>. <NUM>]-<NUM>-nonene (DBN) and <NUM>,<NUM>-diazabicyclo[<NUM>. <NUM>]-<NUM>-undecene (DBU). These may be used singly, or a plurality may be used together.

Of these, organometallic compounds selected from among organotin compounds, organotitanium compounds and organoaluminum compounds are preferred in the inventive composition. Preferred examples include dibutyltin dilaurate, dibutyltin dioctoate, dibutyltin diacetate, dioctyltin dilaurate, dioctyltin dioctoate, dioctyltin diacetate, dibutyltin bis(acetylacetate), dioctyltin bisacetyllaurate, tetrabutyl titanate, tetranonyl titanate, tetrakis(ethylene glycol) methyl ether titanate, tetrakis(ethylene glycol) ethyl ether titanate, bis(acetylacetonyl) dipropyl titanate, acetylacetone aluminum, aluminum (ethyl acetoacetate) mono-n-butyrate, aluminum ethyl acetoacetate di-n-butyrate and aluminum tris(ethyl acetoacetate). In particular, from the standpoint of the reactivity and solubility, tetrabutyl titanate, aluminum ethyl acetoacetate di-n-butyrate, aluminum bis(ethyl acetoacetate) mono-n-butyrate and hydrolysates of these are preferred.

The curing catalyst content per <NUM> parts by weight of the organopolysiloxane compound (A) is preferably from <NUM> to <NUM> parts by weight, and more preferably from <NUM> to <NUM> parts by weight.

The method of preparing the composition of the invention is not particularly limited. The composition can be obtained by mixing together above components (A) and (B) and also any optional ingredients. In particular, in cases where a solvent that includes solvent (B) is used during hydrolytic condensation when preparing component (A), the method preferably includes, for example, the step of hydrolytically condensing a silane compound having a hydrolysable group within a solvent that includes solvent (B) so as to obtain a liquid mixture containing (A) an organopolysiloxane compound having a structure of average formula (I) and solvent (B).

The proportion of the solvent (B) within the solvent containing the solvent (B) is preferably from <NUM> to <NUM> wt%, and more preferably from <NUM> to <NUM> wt%, although the solvent used may consist solely of the solvent (B). Specific examples of organic solvents other than solvent (B) include methanol, ethanol, propanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, toluene and xylene. When an organic solvent other than solvent (B) is used, the method of preparing the inventive composition may include the step of replacing the organic solvent with solvent (B) by treatment such as a stripping operation.

The above-described composition of the invention can be suitably used as a coating material, particularly in exterior wall coating applications, and may be used in other applications as well. For example, by applying the inventive composition onto at least one side of a substrate --and when applying it to one side doing so either directly or over one or more other layer-- and then curing the applied composition so as to form a film, a coated article having a cured film of the coating material formed on at least one side of the substrate, either directly or over one or more other layer, can be obtained.

Examples of the substrate include, but are not particularly limited to, glass, silicon wafers, metals, plastic molded bodies, ceramics, and composites of these.

Use can also be made of any of these substrates in which the surface has been chemical conversion treated, corona discharge treated, plasma treated or treated with an acid or alkali solution, and decorative plywood in which the substrate main body and surface layer are covered with different types of coatings. The other layer or layers are exemplified by layers obtained by polyester resin coating, polyurethane resin coating, amino alkyd resin coating, lacquer coating, spray coating and aqueous wax coating.

A known technique may be suitably selected as the method for applying the coating material onto a substrate. Various types of coating methods may be used, including, for example, flow coating, spin coating, bar coating, wire bar coating, brush coating, spraying, dip coating, roll coating, curtain coating and knife coating. The coating amount is not particularly limited, although an amount such that the thickness of the film after drying is preferably from <NUM> to <NUM>,<NUM>, and more preferably from <NUM> to <NUM>, is generally desirable.

Examples of methods for curing the composition include room-temperature curing and heat curing.

The heating temperature, although not particularly limited, is preferably between <NUM> and <NUM>, and more preferably between <NUM> and <NUM>.

Examples and Comparative Examples are given below to more concretely illustrate the invention.

In the Examples below, the nonvolatile content is a value measured in accordance with JIS C2133. The weight-average molecular weight is a value measured with a gel permeation chromatography (GPC) system (HLC-<NUM>, from Tosoh Corporation) and using tetrahydrofuran (THF) as the developing solvent. Also, the values of "a" to "e" in average formula (I) were calculated from <NUM>H-NMR and <NUM>Si-NMR measurement results.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of phenyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of diethylene glycol diethyl ether (Nippon Nyukazai Co. ) were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Volatile constituents such as methanol were distilled off under reduced pressure, and filtration under pressure was carried out.

The resulting composition was a liquid that had a viscosity of <NUM>,<NUM> mPa·s, a nonvolatiles content of <NUM> wt%, a component (B) content within the composition of from <NUM> to <NUM> wt% (at least <NUM> wt% of the nonvolatiles content being component (B); the same applies below) and a silicone component (exclusive of the solvent) weight-average molecular weight of <NUM>,<NUM>, and was viscous at <NUM>. The values of "a" to "e" in average formula (I) were respectively a = <NUM>, b = <NUM>, c = <NUM>, d = <NUM> and e = <NUM>.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of dimethyldimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> (<NUM> mol) of phenyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of diethylene glycol diethyl ether (Nippon Nyukazai Co. ) were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Volatile constituents such as methanol were distilled off under reduced pressure, and filtration under pressure was carried out.

The resulting composition was a liquid that had a viscosity of <NUM>,<NUM> mPa·s, a nonvolatiles content of <NUM> wt%, a component (B) content within the composition of from <NUM> to <NUM> wt% and a silicone component (exclusive of the solvent) weight-average molecular weight of <NUM>,<NUM>, and was viscous at <NUM>. The values of "a" to "e" in average formula (I) were respectively a = <NUM>, b = <NUM>, c = <NUM>, d = <NUM> and e = <NUM>.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of phenyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> (<NUM> mol) of diphenyldimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of diethylene glycol diethyl ether (Nippon Nyukazai Co. ) were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Volatile constituents such as methanol were distilled off under reduced pressure, and filtration under pressure was carried out.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of dimethyldimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> (<NUM> mol) of phenyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> (<NUM> mol) of diphenyldimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of diethylene glycol diethyl ether (Nippon Nyukazai Co. ) were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Volatile constituents such as methanol were distilled off under reduced pressure, and filtration under pressure was carried out.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of phenyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of dipropylene glycol dimethyl ether (Nippon Nyukazai Co. ) were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Volatile constituents such as methanol were distilled off under reduced pressure, and filtration under pressure was carried out.

Tetramethoxysilane in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> (<NUM> mol) of hexamethyldisiloxane, <NUM> of methanesulfonic acid and <NUM> of dipropylene glycol dimethyl ether (Nippon Nyukazai Co. ) were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Volatile constituents such as methanol were distilled off under reduced pressure, and filtration under pressure was carried out.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of vinyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of dipropylene glycol dimethyl ether (Nippon Nyukazai Co. ) were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Volatile constituents such as methanol were distilled off under reduced pressure, and filtration under pressure was carried out.

The resulting composition was a liquid that had a viscosity of <NUM> mPa·s, a nonvolatiles content of <NUM> wt%, a component (B) content within the composition of from <NUM> to <NUM> wt% and a silicone component (exclusive of the solvent) weight-average molecular weight of <NUM>,<NUM>. The values of "a" to "e" in average formula (I) were respectively a = <NUM>, b = <NUM>, c = <NUM> d = <NUM> and e = <NUM>.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of octyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of dipropylene glycol dimethyl ether (Nippon Nyukazai Co. ) were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Volatile constituents such as methanol were distilled off under reduced pressure, and filtration under pressure was carried out.

The resulting composition was a liquid that had a viscosity of <NUM>,<NUM> mPa·s, a nonvolatiles content of <NUM> wt%, a component (B) content within the composition of from <NUM> to <NUM> wt% and a silicone component (exclusive of the solvent) weight-average molecular weight of <NUM>,<NUM>. The values of "a" to "e" in average formula (I) were respectively a = <NUM>, b = <NUM>, c = <NUM>, d = <NUM> and e = <NUM>.

The composition was prepared by adding <NUM> parts by weight of the aluminum alkoxide compound DX-<NUM> (from Shin-Etsu Chemical Co. ; a mixture of aluminum ethyl acetoacetate di-n-butyrate and aluminum bis(ethyl acetoacetate) mono-n-butyrate) as the curing catalyst to <NUM> parts by weight of the organopolysiloxane composition obtained in Reference Example <NUM>-<NUM>.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of phenyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of toluene were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Following filtration, methanol was removed by a water-washing step, and purification was carried out by filtration under pressure.

The resulting composition was a liquid that had a viscosity of <NUM> mPa·s, a nonvolatiles content of <NUM> wt%, a component (B) content within the composition of <NUM> wt% and a silicone component (exclusive of the solvent) weight-average molecular weight of <NUM>,<NUM>. The values of "a" to "e" in average formula (I) were respectively a = <NUM>, b = <NUM>, c = <NUM>, d = <NUM> and e = <NUM>.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of dimethyldimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> (<NUM> mol) of phenyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of toluene were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Following filtration, methanol was removed by a water-washing step, and purification was carried out by filtration under pressure.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of phenyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> (<NUM> mol) of diphenyldimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of toluene were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Following filtration, methanol was removed by a water-washing step, and purification was carried out by filtration under pressure.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of dimethyldimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> (<NUM> mol) of phenyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> (<NUM> mol) of diphenyldimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of toluene were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Following filtration, methanol was removed by a water-washing step, and purification was carried out by filtration under pressure.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of phenyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of toluene were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Following filtration, methanol and toluene were removed by distillation under reduced pressure and <NUM> of methyl ethyl ketone was added, after which purification was carried out by filtration under pressure.

Methyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ) in an amount of <NUM> (<NUM> mol), <NUM> (<NUM> mol) of phenyltrimethoxysilane (KBM-<NUM>, from Shin-Etsu Chemical Co. ), <NUM> of methanesulfonic acid and <NUM> of toluene were blended in a reactor until uniform, at which point <NUM> of deionized water was added and the mixture was stirred at <NUM> for <NUM> hours. Neutralization was then carried out by adding <NUM> of magnesium aluminum hydroxide carbonate hydrate (Kyowaad 500SH (Kyowa Chemical Industry Co. ) and stirring for <NUM> hours. Following filtration, methanol and toluene were removed by distillation under reduced pressure and <NUM> of ethyl acetate was added, after which purification was carried out by filtration under pressure.

The compositions obtained in Reference Examples <NUM>-<NUM> to <NUM>-<NUM>, <NUM>-<NUM> and <NUM>-<NUM>, Examples <NUM>-<NUM>, <NUM>-<NUM> and <NUM>-<NUM>, and Comparative Examples <NUM>-<NUM> to <NUM>-<NUM> were applied onto glass substrates by flow coating, and baking was carried out by heating for <NUM> hours in a <NUM> dryer. The content of component (B) within the compositions of the Examples was <NUM> wt% or more.

In the resulting coated articles, the appearance of the cured film (coat) was visually evaluated and the adhesion was measured. The results are shown in Table <NUM>.

Cured films for which the film surface when visually examined was uniform and free of hard spots and cracking were rated as "OK"; those in which cracking or hard spots arose were rated as "NG.

A cross-cut test with <NUM> squares was carried out in accordance with JIS K5600-<NUM>-<NUM>. The results are shown in the table as (number of squares that remain and do not peel off)/<NUM>.

Claim 1:
A composition comprising (A) an organopolysiloxane compound having a structure of the average formula (I) below and (B) <NUM> to <NUM> wt% of dipropylene glycol dimethyl ether

        (SiO<NUM>/<NUM>)a(R<NUM>SiO<NUM>/<NUM>)b(R<NUM><NUM>SiO<NUM>/<NUM>)c(R<NUM><NUM>SiO<NUM>/<NUM>)d(R<NUM>O<NUM>/<NUM>)e     (I)

wherein each R<NUM> independently is a hydrogen atom or an alkyl group, aralkyl group or aryl group of <NUM> to <NUM> carbon atoms which may be substituted with halogen atoms; R<NUM> is a hydrogen atom, methyl group, ethyl group, n-propyl group or i-propyl group; "a", "b", "c" and "d" are respectively numbers which satisfy the conditions <NUM> ≤ a < <NUM>, <NUM> < b ≤ <NUM>, <NUM> ≤ c < <NUM>, <NUM> ≤ d < <NUM> and a+b+c+d = <NUM>; and "e" is a number which satisfies the condition <NUM> < e ≤ <NUM>.