Abstract:
An improved thickening composition for organic systems, including paints and coatings, is described. The additive provides paints and coatings more than adequate viscosity improvement without affecting intercoat adhesion characteristics. 
     REEXAMINATION RESULTS 
     The questions raised in reexamination request no. 90/007130, filed Jul. 21, 2004, have been considered and the results thereof are reflected in this reissue patent which constitutes the reexamination certificate required by 35 U. S. C. 307 as provided in 37 CFR 1.570(e), for  ex parte  reexamination, or the reexamination certificate required by 35 U. S. C. 316 as provided in 37 CFR 1.997(e) for  inter partes  reexamination.

Description:
BACKGROUND OF THE INVENTION 
     1. Brief Description of the Invention 
     The invention described herein involves improved thickening compositions often referred to as Theological additives, viscosity modifiers or thixotropes, used to impart rheological and viscosity modification properties to a wide range of oil and organic based systems used as paints and coatings. In many commercial applications, such a thickening Theological chemical is added to an oil or organic based paint or coating system, for example epoxy paint, to change or modify the rheological properties of the system. The invention also includes paints and coatings containing such additives. 
     In an important aspect the invention covers a Theological additive consisting of the reaction product of:
         a) a diamine selected from the group consisting of ethylene diamine and hexamethylene diamine;   b) one or more straight chain monocarboxylic acids having 4 to 8 carbon atoms; and   c) 12-hydroxystearic acid.       

     The invention is based on a discovery that certain castor based rheological additives, while imparting desirable rheology, impair recoatability and intercoat adhesion of the system in which they are utilized where such systems, after driving, is painted or coated over with a second paint or coating composition. The present invention shows that these undesirable side effects can be avoided by using the inventive additives. 
     Normally Theological additives should show no reactivity, so they do not react with any other ingredients in the systems in which they are used. Intercoat adhesion is defined as adhesion between adjacent layers of paint when more than one coat of paint or coating is applied to a substrate. Examples of such use are primer and topcoats in home painting and a series of paint coatings applied to automobiles and appliances. 
     We have concluded it is essential when using additives to structure their chemistry so that, at necessary dosage, they do not adversely affect paint and coating compositions used by customers in systems where more than one coat will be applied to a substrate. 
     2. Description of the Prior Art 
     It has been known in the art for many years to use various materials as rheological additives to, among other Theological properties, modify the viscosity of organic systems. Such systems can include paints and coatings, inks, construction materials and wood stains. Depending on the composition of the system, the products made with these thickeners are preferably useful as coatings and paints. 
     The present invention includes novel rheological additives as well as organic fluid composition containing such additives. 
     Rheology is defined as the science of the flow and deformation of matter. Rheological additives can be defined as substances added to liquid systems which change that system&#39;s flow and viscosity properties. Proper rheology for storage and application must be balanced with the requirement of many fluid systems to resist sagging and dripping during and following application. The term “thixotropy” describes a type of flow behavior in which a temporary reduction in a fluid&#39;s viscosity by the application of shear, such as through the use of a paintbrush or atomizing equipment; once the shear forces have been removed, such as following deposition of the liquid onto a surface), the system will regain its initial, higher viscosity. 
     For background, Japanese Patent Application No. 62-69957 describes a sag preventor for non-aqueous coating materials comprising a mixture of two different fatty acid amides wherein fatty acid amide (A) is obtained by reacting a mixture of at least one straight chain saturated fatty acid having 3-4 carbon atoms and 12-hydroxystearic acid (the molar ratio of the fatty acid and 12-hydroxystearic acid being 1:9-8:1) and ethylene diamine or hexamethylene diamine and fatty acid amide (B) is obtained by reacting a mixture of at least one straight chain saturated fatty acid having 6-22 carbon atoms and 12-hydroxystearic acid (the molar ratio of the fatty acid and 12-hydroxystearic acid being 0:10-8:2) and ethylene diamine, hexamethylene diamine, or xylyiene diamine wherein the weight ratio of fatty acid amide (A) to fatty acid amide (B) is 100:00-20:80. 
     Products believed to be the reaction product of ethylene diamine, a monocarboxylic acid having ten carbon atoms and 12-hydroxystearic acid have been sold for many years as Theological additives. A product, designated comparative X, using this chemistry has been used as a comparative example to the invention hereof in the below following examples. 
     OBJECT OF THE INVENTION 
     It is an object of the present invention to solve or substantially alleviate the problems created by prior art thickeners in thickening compositions for organic systems. It is, therefore, a more specific object of the present invention to an additive which will provide paints and coatings without affecting intercoat adhesion. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     This invention provides amide compositions having at least two amide moieties per molecule which comprises reacting preferably by known condensation reactions, a diamine selected from ethylene diamine, hexamethylene and mixtures thereof diamine and mixtures thereof, one or more monocarboxylic acid of the formula:
 
R 1 —COOH 
 
wherein R 1  is a straight chain saturated aliphatic hydrocarbon radical of 3 to 7 carbon atoms and 12-hydroxystearic acid. The inventors have found that the inventive composition provides improved rheological and suspension properties to non-aqueous coating systems and more importantly the inventive composition does not cause intercoat adhesion failures of topcoats subsequently applied to primers.
 
     In an important aspect the invention covers a rheological additive consisting of the reaction product of:
         a) a diamine selected from the group consisting of ethylene diamine and hexamethylene diamine;   b) one or more straight chain monocarboxylic acids having 3 to 7 carbon atoms in the straight chain saturated aliphatic hydrocarbon radical; and   c) 12-hydroxystearic acid.       

     The invention preferably relates to a composition, which is obtained by reacting
         a) 2 equivalents of a chemical selected from ethylene diamine, hexamethylene diamine and mixtures thereof;   b) from 0.4 to 1.8 equivalents of a straight chain monocarboxylic acid having 3 to 7 carbon atoms in the straight chain saturated aliphatic hydrocarbon radical; and   c) from 1.6 to 0.2 equivalents of 12-hydroxystearic acid, such that no essentially free acid and amine is left unreacted at the end of the condensation reaction.       

     A most preferably aspect of this invention relates to a rheological additive composition consisting of a reaction product of:
         1) ethylene diamine;   2) one or more straight chain monocarboxylic acids having 3-7 carbon atoms in the straight chain saturated aliphatic hydrocarbon radical; and   3) 12-hydroxystearic acid.
 
wherein the equivalent ratio of monocarboxylic acid and 12-hydroxystearic acid is 0.4:1.6 to 1.8:0.2 and there are 2 equivalents of ethylene diamine.
       

     The term “equivalent(s)” is used and is intended to have its standard meaning as employed in the art (see for example Hawley&#39;s Condensed Chemical Dictionary 1987, 11 th  Edition). However, for additional clarity, equivalents refer to the number of reactive groups present in a molar quantity of a molecule, such that a mole of a diamine (e.g. ethylene diamine) has two equivalents of amine and a mole of 12-hydroxystearic acid has one equivalent of carboxylic acid. Furthermore a monoacid has only one reactive group and a diamine has only two reactive groups (preferably both primary amines), and a monocarboxylic acid has one carboxylic acid group and these are preferable, although not necessarily, the only reactive materials present in the reaction mixture. 
     The diamines of component a) useful for the present invention include ethylene diamine and hexamethylene diamine with the most preferred being ethylene diamine. Hexamethylene diamine is often referred to as hexane diamine. These are common chemicals and can be obtained from a large number of chemical manufacturers. 
     The chemicals useful for component b) include monocarboxylic acids of the formula R 1 —COOH were R 1  is between 3 and 7. Such acids are commercially available and include butyric acid, pentanoic acid, hexanoic acid, heptanoic acid and octanoic acid. The monocarboxylic acid of the formula R 1 —COOH wherein R 1  is C 8  and above falls outside the preferred acids. A preferred acid is heptanoic acid with the most preferred hexanoic acid. These acids are commercially available for example from Acme Hardesty Company, Penta Manufacturing Company and Procter and Gamble Company and others. 
     Component (c) is 12-hydroxystearic acid. This acid is produced from hydrogenated castor oil and is a straight C 18  carbon chain saturated fatty acid with an OH group attached to the 12 th  carbon atom. Suppliers of such products include, for example, CASCHEM, Inc and Acme-Hardesty Company. 
     Generally the Theological additives of the present invention are preferably prepared according to known condensation reaction. The diamine, monocarboxylic acid and 12-hydroxystearic acid are reacted together in stoichiometric amounts so that no excess of the acid or the amine is left unreacted. The order of the addition of the co-reactants is not generally important and these can be added either at ambient temperature or at reaction temperature. For example, the reactants may be charged in increments to a suitable reaction vessel equipped with a mechanical stirrer, a thermometer, a Dean-Stark adapter or other water collector and a nitrogen inlet. The vessel containing the reactants is heated under a blanket of nitrogen. The reaction may be carried out under atmospheric pressure or under vacuum. The reaction temperature to be used in the synthesis may be varied, but preferably ranges from ambient temperature to 300° C. under normal pressure. More preferably, the temperature ranges from ambient to 250° C., and most preferably from 120 to 220° C. Water is removed as condensate as the reaction progresses. After the completion of the reaction, the additive is cooled to 140-150° C. and discharged into a release box and allowed to cool overnight. The product is then cooled with liquid nitrogen, dried and ground cryogenically to a fine powder using a Brinkmann centrifugal mill. 
     The rheological additives used in the present invention may be synthesized with or without a catalyst. The catalyst, if used, may be selected from those, which are normally used for condensation reactions. Examples of such catalysts include, but are not limited to, sulfuric acid, orthophosphoric acid, p-toluene sulfonic acid, dibutytin dilaurate, tetraalkyl tin or titanium compounds, metal hydrides and the like. A preferred catalyst is orthophosphoric acid. The catalyst should generally be used in an amount of from about 0.001 to 2.5 percent by weight based on the total weight of the reactants. 
     Inventive paints and coatings can be prepared using present standard and diverse paint and coatings base formulations by merely replacing existing Theological additives with the inventive additives described above. Amounts of additives used are normally between 0.5 to 3.5% of the base formulation. Alkyd enamel paints, air drying alkyd paints, long oil alkyd baking paints, two-pack epoxy polyamide primer paints and pvc topcoats are preferred paint coating systems. 
     EXAMPLES 
     The following examples are illustrations designed to assist those skilled in the art to practice the present invention, but are not intended to limit the invention. Changes can be made without departing from the spirit of the invention. The various chemicals used in the examples were commercially obtained materials. 
     Example 1 
     A number of additives were made using the teaching of this invention as follows. 
     To a 500-ml resin kettle equipped with a thermometer, a Dean-Stark adapter, a water-cooled condenser, a mechanical stirrer and a nitrogen inlet, 25.84 grams (0.43 mole, 0.86 equivalents) ethylene diamine, 49.95 grams (0.43 mole, 0.43 equivalents) hexanoic acid, 132.75 grams (0.43 mole, 0.43 equivalents) 12-hydroxystearic acid and 0.04 gram phosporic acid as catalyst were charged. The mixture was heated to 200° C. with stirring under a blanket of nitrogen with a steady flow of the inert gas. Water start to come off at 150°-155° C. After an hour at 200° C., aliquots are taken hourly and the acid and amine values are determined. The reaction is continued until the acid and amine values are below 10. The reaction product is cooled to 120° C. and is dischaged into a release box and allowed to cool to room temperature. The product is then cooled under liquid nitrogen and ground cryogenically to a fine powder using a Brinkmann centrifugal mill. 
     Examples 2-31 
     The general procedure outlined in Example 1 was used, except that the reacts we replaced as indicated in Table 1. 
     
       
         
               
               
               
               
             
               
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 Example 
                 Reagents 
                 Moles 
                 Equivalents 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 2 
                 Ethylene diamine 
                 0.43 
                 0.86 
               
               
                   
                 Hexanoic acid 
                 0.473 
                 0.473 
               
               
                   
                 12-Hydroxystearic acid 
                 0.387 
                 0.387 
               
               
                 3 
                 Ethylene diamine 
                 0.43 
                 0.86 
               
               
                   
                 Hexanoic acid 
                 0.387 
                 0.387 
               
               
                   
                 12-Hydroxystearic acid 
                 0.473 
                 0.473 
               
               
                 4 
                 Ethylene diamine 
                 0.6 
                 0.12 
               
               
                   
                 Hexanoic acid 
                 0.84 
                 0.84 
               
               
                   
                 12-Hydroxystearic acid 
                 0.36 
                 0.36 
               
               
                 5 
                 Ethylene diamine 
                 0.7 
                 1.4 
               
               
                   
                 Hexanoic acid 
                 1.05 
                 1.05 
               
               
                   
                 12-Hydroxystearic acid 
                 0.35 
                 0.35 
               
               
                 6 
                 Ethylene diamine 
                 0.7 
                 1.4 
               
               
                   
                 Hexanoic acid 
                 1.12 
                 1.12 
               
               
                   
                 12-Hydroxystearic acid 
                 0.28 
                 0.28 
               
               
                 7 
                 Ethylene diamine 
                 0.75 
                 1.5 
               
               
                   
                 Hexanoic acid 
                 1.275 
                 1.275 
               
               
                   
                 12-Hydroxystearic acid 
                 0.225 
                 0.225 
               
               
                 8 
                 Ethylene diamine 
                 0.5 
                 1.0 
               
               
                   
                 Hexanoic acid 
                 0.4 
                 0.4 
               
               
                   
                 12-Hydroxystearic acid 
                 0.6 
                 0.6 
               
               
                 9 
                 Ethylene diamine 
                 0.4 
                 0.8 
               
               
                   
                 Hexanoic acid 
                 0.28 
                 0.28 
               
               
                   
                 12-Hydroxystearic acid 
                 0.52 
                 0.52 
               
               
                 10 
                 Ethylene diamine 
                 0.4 
                 0.8 
               
               
                   
                 Hexanoic acid 
                 0.24 
                 0.24 
               
               
                   
                 12-Hydroxystearic acid 
                 0.56 
                 0.56 
               
               
                 11 
                 Ethylene diamine 
                 0.4 
                 0.8 
               
               
                   
                 Hexanoic acid 
                 0.2 
                 0.2 
               
               
                   
                 12-Hydroxystearic acid 
                 0.6 
                 0.6 
               
               
                 12 
                 Ethylene diamine 
                 0.35 
                 0.70 
               
               
                   
                 Hexanoic acid 
                 0.14 
                 0.14 
               
               
                   
                 12-Hydroxystearic acid 
                 0.56 
                 0.56 
               
               
                 13 
                 Ethylene diamine 
                 0.43 
                 0.86 
               
               
                   
                 Heptanoic acid 
                 0.43 
                 0.43 
               
               
                   
                 12-Hydroxystearic acid 
                 0.43 
                 0.43 
               
               
                 14 
                 Ethylene diamine 
                 0.44 
                 0.88 
               
               
                   
                 Heptanoic acid 
                 0.484 
                 0.484 
               
               
                   
                 12-Hydroxystearic acid 
                 0.396 
                 0.396 
               
               
                 15 
                 Ethylene diamine 
                 0.43 
                 0.86 
               
               
                   
                 Heptanoic acid 
                 0.387 
                 0.387 
               
               
                   
                 12-Hydroxystearic acid 
                 0.473 
                 0.473 
               
               
                 16 
                 Ethylene diamine 
                 0.5 
                 1.0 
               
               
                   
                 Heptanoic acid 
                 0.6 
                 0.6 
               
               
                   
                 12-Hydroxystearic acid 
                 0.4 
                 0.4 
               
               
                 17 
                 Ethylene diamine 
                 0.5 
                 1.0 
               
               
                   
                 Heptanoic acid 
                 0.4 
                 0.4 
               
               
                   
                 12-Hydroxystearic acid 
                 0.5 
                 0.6 
               
               
                 18 
                 Ethylene diamine 
                 0.5 
                 1.0 
               
               
                   
                 Heptanoic acid 
                 0.55 
                 0.55 
               
               
                   
                 12-Hydroxystearic acid 
                 0.45 
                 0.45 
               
               
                 19 
                 Ethylene diamine 
                 0.5 
                 1.0 
               
               
                   
                 Heptanoic acid 
                 0.45 
                 0.45 
               
               
                   
                 12-Hydroxystearic acid 
                 0.55 
                 0.55 
               
               
                 20 
                 Ethylene diamine 
                 0.6 
                 1.2 
               
               
                   
                 Heptanoic acid 
                 0.84 
                 0.84 
               
               
                   
                 12-Hydroxystearic acid 
                 0.36 
                 0.36 
               
               
                 21 
                 Ethylene diamine 
                 0.5 
                 1.0 
               
               
                   
                 Heptanoic acid 
                 0.3 
                 0.3 
               
               
                   
                 12-Hydroxystearic acid 
                 0.7 
                 0.7 
               
               
                 22 
                 Ethylene diamine 
                 0.6 
                 1.2 
               
               
                   
                 Heptanoic acid 
                 0.9 
                 0.9 
               
               
                   
                 12-Hydroxystearic acid 
                 0.3 
                 0.3 
               
               
                 23 
                 Ethylene diamine 
                 0.7 
                 1.4 
               
               
                   
                 Heptanoic acid 
                 1.12 
                 1.12 
               
               
                   
                 12-Hydroxystearic acid 
                 0.28 
                 0.28 
               
               
                 24 
                 Ethylene diamine 
                 0.7 
                 1.4 
               
               
                   
                 Heptanoic acid 
                 1.19 
                 1.19 
               
               
                   
                 12-Hydroxystearic acid 
                 0.21 
                 0.21 
               
               
                 25 
                 Ethylene diamine 
                 0.7 
                 1.4 
               
               
                   
                 Heptanoic acid 
                 1.26 
                 1.26 
               
               
                   
                 12-Hydroxystearic acid 
                 0.14 
                 0.14 
               
               
                 26 
                 Ethylene diamine 
                 0.7 
                 1.4 
               
               
                   
                 Heptanoic acid 
                 1.085 
                 1.085 
               
               
                   
                 12-Hydroxystearic acid 
                 0.315 
                 0.315 
               
               
                 27 
                 Ethylene diamine 
                 0.45 
                 0.90 
               
               
                   
                 Butyric acid 
                 0.45 
                 0.45 
               
               
                   
                 12-Hydroxystearic acid 
                 0.45 
                 0.45 
               
               
                 28 
                 Ethylene diamine 
                 0.45 
                 0.90 
               
               
                   
                 Pentanoic acid 
                 0.45 
                 0.45 
               
               
                   
                 12-Hydroxystearic acid 
                 0.45 
                 0.45 
               
               
                 29 
                 Ethylene diamine 
                 0.43 
                 0.86 
               
               
                   
                 Octanoic acid 
                 0.43 
                 0.43 
               
               
                   
                 12-Hydroxystearic acid 
                 0.43 
                 0.43 
               
               
                 30 
                 Hexane diamine 
                 0.5 
                 1.0 
               
               
                   
                 Hexanoic acid 
                 0.5 
                 0.5 
               
               
                   
                 12-Hydroxystearic acid 
                 0.5 
                 0.5 
               
               
                 31 
                 m-Xylylene Diamine 
                 0.45 
                 0.90 
               
               
                   
                 Hexanoic acid 
                 0.45 
                 0.45 
               
               
                   
                 12-Hydroxystearic acid 
                 0.45 
                 0.45 
               
               
                   
               
             
          
         
       
     
     EVALUATION OF RHEOLOGICAL ADDITIVES 
     Test One 
     All the materials prepared according to Examples 1-31 were incorporated by dispersing into a long oil alkyd baking enamel paint system at a loading of 7.2 pounds per hundred gallons (pphg) and a number of tests were conducted to demonstrate the effectiveness of the respective rheological additive as to common rheological properties of the type shown below. 
     After the paints were made, they were allowed to equilibrate at room temperature overnight, and the paint properties were measured as described below:
         (1) Fineness of grind (indicative of dispersibility) was measured in Hegman units using a wide path Hegman gauge in accordance with ASTM D1210-79.   (2) Brookfield viscosities at 10 and 100 RPM were measured with a Brookfield Model RVT viscometer in accordance with ASTM D2196-81. From viscosity data, a Thixotropic Index (TI) was calculated as follows:
 
Thixotropic Index (TI)=10 RPM Viscosity+100 RPM Viscosity 
   (3) Sag resistance was measured in mils using a Leneta Sag multi notch applicator at room temperature in accordance with ASTM D4400-84.   (4) In some instances Stormer viscosities were measured in Krebs Units (KU) with a Thomas Stormer Instrument, Model #09730-G15, in accordance with ASTM D562-81.       

     Gloss measurements were measured at 60° and/or 20° in accordance with ASTM D523-80. Drawdowns were prepared of paints according to Formulation A, and the 60° and/or 20° gloss determined after curing the film for 24 hours at room temperature. The preparation and components of the long oil alkyd baking enamel paint system are described in Formulation A. The results are set forth in Table 2. 
     Additionally, samples of rheological additives of the present invention were evaluated for Brookfield viscosities and intercoat adhesion in a two-pack epoxy primer. The preparation and components of the epoxy primer two component paint system are described in Formulation B. The results of the tests in a two-pack epoxy primer are set forth in Table 3. PVC topcoat formulation used for intercoat adhesion test is described in Formulation C. The intercoat adhesion test method and the spray conditions are described below. 
     The results of the intercoat adhesion in the two-pack epoxy primer are set forth in Table 4. The spray conditions used for intercoat adhesion test are set forth in Table 5. 
     Additionally, the samples of the rheological additives of the invention were evaluated in an air drying short oil alkyd paint system. The preparation and components of the short oil alkyd paint system are described in Formulation D. The results are set forth in Table 6. 
     In order to compare the rheological properties of the inventive additives with common prior art additives, several comparative examples were made and tested. 
     Comparative Example 1 
     A long oil alkyd enamel paint was prepared according to the procedure described in Formulation A to which was added a rheological additive designated as Comparative X which uses the chemistry described above. The paint properties were evaluated and set forth in Table 2. 
     Comparative Example 2 
     A two-pack epoxy primer was prepared according to the procedure described in Formulation B without a rheological additive. The intercoat adhesion properties were evaluated and are set forth in Table 4. 
     Comparative Example 3 
     A two-pack epoxy primer was prepared according to the procedure described in Formulation B with Comparative X rheological additive. The paint properties were evaluated and are set forth in Table 3 and intercoat adhesion properties were evaluated and set forth in Table 4. 
     Comparative Example 4 
     An air drying short oil alkyd paint was prepared according to the procedure described in Formulation D without a rheological additive. The paint properties were evaluated and set forth in Table 6. 
     Comparative Example 5 
     An air drying short oil alkyd enamel paint was prepared according to the procedure described in Formulation D with Comparative X rheological additive. The paint properties were evaluated and set forth in Table 6. 
     
       
         
               
             
               
               
               
               
             
               
               
               
               
             
           
               
                   
               
               
                 FORMULATION A 
               
               
                 LONG OIL ALKYD BAKING ENAMEL PAINT 
               
             
          
           
               
                 Component 
                 Function 
                 Pounds 
                 Gallons 
               
               
                   
               
             
          
           
               
                 Beckosol 10-060 
                 Alkyd binder, 
                 105.76 
                 13.22 
               
               
                   
                 Reichhold Chemicals 
               
               
                 Mineral Spirits 66/3 
                 Solvent 
                 70.60 
                 10.91 
               
               
                 Rheological additive 
                 Rheological additive 
                 7.20 
                 0.51 
               
               
                 Mix 3 minutes @ 
               
               
                 3000 RPM, then add 
               
               
                 Methanol 95/5 
                 Solvent 
                 2.38 
                 0.35 
               
               
                 Mix 2 minutes # 
               
               
                 3000 RPM, then add 
               
               
                 KRONOS 2101 
                 Titanium dioxide 
                 325.00 
                 9.37 
               
               
                 Disperse 15 minutes @ 
               
               
                 5000 RPM 
               
               
                 Let down: 
               
               
                 Beckosol 10-060 
                 Alkyd binder, 
                 445.90 
                 55.74 
               
               
                   
                 Reichhold Chemicals 
               
               
                 Mineral Spirits 66/3 
                 Solvent 
                 54.70 
                 8.45 
               
               
                 6% Zirconium Nuxtra 
                 Drier, Hüls 
                 5.40 
                 0.75 
               
               
                 6% Calcium Nuxtra 
                 Drier, Hüls 
                 4.00 
                 0.51 
               
               
                 6% Cobalt Nuxtra 
                 Drier, Hüls 
                 5.22 
                 0.70 
               
               
                 Exkin #2 
                 Antiskinning agent, 
                 1.10 
                 0.14 
               
               
                   
                 Hüls 
               
               
                 Mix 10 minutes @ low speed 
                   
                   
               
               
                   
                   
                 1027.26 
                 100.65 
               
               
                   
               
             
          
         
       
     
                                                                         TABLE 2                   Results in a long oil alkyd baking enamel paint system       Rheological additive: 7.2 pphg                    Brookfield       Leneta               Stormer   viscosity, cP       Sag   Gloss,       Example   Viscosity, KU   10/100 rpm   T.I.   (mils)   60°                    Comparative X   97   4800/1920   2.50   13   85       Inventive   100.8   4640/2156   2.15   11   84       Example 1       Inventive   95   4200/1652   2.54   11.4   83       Example 4       Inventive   101   6480/2084   3.11   15   86       Example 5       Inventive   98   5320/1876   2.84   13.6   87       Example 6       Inventive   92   3440/1472   2.34   8   82       Example 7       Inventive   95.7   3000/1692   1.77   6.9   85       Example 8       Inventive   92.7   2160/1424   1.52   5.9   85       Example 9       Inventive   90.6   1680/1276   1.32   4.8   84       Example 10       Inventive   88.7   1280.1136   1.13   3.8   84       Example 11       Inventive   88.2   1160/1076   1.08   3.7   88       Example 12       Inventive   89   2200/1212   1.82   5   80       Example 17       Inventive   95   4080/1600   2.55   11   79       Example 18       Inventive   84   1320/956    1.38   4   81       Example 19       Inventive   104   7840/2260   3.47   15   79       Example 20       Inventive   91   2520/1360   1.85   6   79       Example 21       Inventive   106   9680/2632   3.68   18   84       Example 22       Inventive   105   9440/2631   3.59   17   85       Example 23       Inventive   100   6160/2080   2.96   12   80       Example 24       Inventive   103   7289/2232   3.26   14   80       Example 25       Inventive   107.4   9840/2692   3.65   20   85       Example 26       Inventive   92   2520/1444   1.75   6   84       Example 27       Inventive   98.9   3326/1884   1.76   7   81       Example 28       Inventive   89   2320/1348   1.72   5   81       Example 30       Inventive   93   2240/1444   1.55   4.4   81       Example 31                    
Discussion of Results: As may be seen from the data set forth above, the rheological additives of the present invention as described in the Inventive Examples are effective Theological additives providing excellent properties of high viscosity, anti-sagging and high thixotropic index and maintaining good gloss.
 
     
       
         
               
             
               
               
               
             
               
               
               
             
           
               
                   
               
               
                 FORMULATION B 
               
               
                 TWO PACK EPOXY-POLYAMIDE PRIMER 
               
             
          
           
               
                 Component 
                 Function 
                 Weight 
               
               
                   
               
             
          
           
               
                 Epikote 1001/75X 
                 Binder, Shell Chemicals Europe 
                 19.85 
               
               
                 Antiterm U 
                 Wetting agent, Byk Chemie 
                 0.20 
               
               
                   
                 Rheological agent 
                 0.50 
               
               
                 Methyl Isobutyl Ketone 
                 Solvent 
                 6.96 
               
               
                 Xylene 
                 Solvent 
                 13.94 
               
               
                 n-Butanol 
                 Solvent 
                 3.98 
               
               
                 KRONOS 2059 
                 Titanium dioxide, KRONOS Titan 
                 6.96 
               
               
                 Blank Fixe micro 
                 Filler, Sachtleben Chemie 
                 35.65 
               
               
                 Talkum IT extra 
                 Filler, Grolman GmbH 
                 11.96 
               
               
                   
                   
                 100.00 
               
               
                 Component A 
                 Disperse for 30 minutes. 18 m/s, 
               
               
                   
                 50° C. 
               
               
                 Component B 
               
               
                 Versamid 115X70 
                 Hardener 
                 31.00 
               
               
                 Component A + B 
                 Slow stirring for 5 minutes 
                   
               
               
                   
                   
                 131.00 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
             
               
               
               
             
               
             
               
               
               
             
               
             
               
               
               
             
           
               
                   
               
               
                 FORMULATION C 
               
               
                 PVC TOPCOAT 
               
             
          
           
               
                 Component 
                 Function 
                 Weight % 
               
               
                   
               
             
          
           
               
                 Laroflex 
                 PVC-binder, BASF (35% in xylene) 
                 34.75 
               
               
                 MP 35 
               
               
                 Xylene 
                 Solvent 
                 3.84 
               
               
                 BENTONE 38 
                 Rheological additive, Elementis Specialties 
                 0.80 
               
             
          
           
               
                 Disperse for 5 minutes at 18 m/s tooth blade 
               
             
          
           
               
                 KRONOS 2310 
                 Titanium dioxide, KRONOS Titan GmbH 
                 30.35 
               
             
          
           
               
                 Disperse for 20 minutes 18 m/s tooth blade 
               
             
          
           
               
                 Laroflex 
                 PVC-binder, BASF (35% in xylene) 
                 21.26 
               
               
                 MP 35 
               
               
                 Chloroparaffin 
                 Plasticizer 
                 2.68 
               
               
                 50 
               
               
                 Shellsol A 
                 Solvent 
                 6.32 
               
               
                   
                   
                 100.00 
               
               
                   
               
             
          
         
       
     
                                                             TABLE 3                   Results in a two pack epoxy primer       Rheological additive: 0.5%                 Brookfield RVT viscosities (mPa s)                after 1 day            rpm            Example   10   20   50   100   T.I.               Comparative Example 3   26000   14000   7000   4000   6.50       Inventive Example 1   29500   16500   7600   4400   6.70       Inventive Example 4   34000   19000   8500   4800   7.08       Inventive Example 5   34000   18500   8000   4700   7.23       Inventive Example 6   19000   10500   5300   3200   5.94       Inventive Example 7   37000   20000   9200   5100   7.25                    
Discussion of Results: As can be seen from the data set forth above, the additives of the present invention are effective paint additives yielding excellent viscosity results and thixotropic index in the two pack epoxy primer.
 
Tests 2 and 3
 
     One important aspect of this invention is to match prior art compositions in paint properties without affecting intercoat adhesion properties. Prior art compositions show poor intercoat adhesion whereas the inventive example exhibits no intercoat adhesion failures. 
     Test 2 and 3 were run to show the improved intercoat adhesion properties of this invention. It used the below-described method. 
     INTERCOAT ADHESION TEST METHOD 
     1. Equipment and system 
                                                 Test system:   2 part epoxy primer               2 part epoxy primer, commercial system           Top coat:   2 part epoxy primer               PVC top coat               PVC top coat, commercial system           Spraying equipment:   Pneumatic           Spraying conditions:   Spray nozzle with 1.2 mm               Pressure 4-5 bar           Spraying viscosity:   40 s, DIN 4 cup           Substrate:   Steel panel, 30 × 20 cm                        
2. Conditions
 
                                     Application and storage temperatures:   10° C., room temperature, 40° C.       Primer applied:   1 and 3 spray passes       Top coat:   1 and 3 spray passes                    
3. Method
         1. Application of the primer under the above-mentioned conditions with 1 and 3 spray passes.   2. Evaporation of solvents is controlled by covering areas of the sprayed surface directly after the last spray pass, for example with a watch glass or laboratory weight dish. Subsequently and depending on temperature, other areas of the coating are also covered to inhibit solvent evaporation.   3. The primed panels are left to dry for the necessary time at each temperature.   4. The topcoat is then applied under the above conditions also with 1 and 3 spray passes.   5. The panels are then stored at room temperature until dry.   6. Tests by cross hatch and tape method.
 
Test 2
       
                                                                                                                                                                                     TABLE 4                   Results of intercoat adhesion in the two-pack epoxy primer after 1 week storage,       second recoating.                               5° C.   23° C.   40° C.                               1 spray   3 spray   1 spray   3 spray   1 spray   3 spray                          pass   passes   passes   pass   passes   pass            Example   GT   TT   GT   TT   GT   TT   GT   TT   GT   TT   GT   TT            Comparative   1. tin lid   0   0   0   1   0   0   0   0   0   0   0   0       Example 2   2. tin lid   0   0   0   0   0   0   0   0   0   0   0   0           3. tin lid   0   0   1   0   0   0   0   0   0   0   0   0       Comparative   1. tin lid   5   5   3   5   5   5   5   5   5   5   5   5       Example 3   2. tin lid   0   0   0   0   1   0   0   0   1   0   0   0           3. tin lid   1   0   0   0   0   0   0   0   1   0   0   0       Inventive   1. tin lid   1   0   0   0   0   0   0   0   1   0   0   0       Example 1   2. tin lid   1   0   0   0   0   0   0   0   1   0   0   0           3. tin lid   1   0   0   0   0   0   0   0   1   0   1   0               GT (cross hatch):         0 = Good, the cutting lines are totally smooth. No part of the coating is flaked off.         1 = At the cutting intersections about 5% of the surface of the coating is flaked off.         2 = At the cutting lines and at the cutting intersections about 15% of the coating is flaked off.         3 = About 35% of the coating is in small of big stripes flaked off.         4 = At the cutting lines about 65% of the coating is flaked off.         5 = More that 65% of the coating is flaked off.         TT (tape test): 0 = good/5 = poor, coat is totally peeled off.              
Discussion of Results: As can be seen from the data set forth above, the rheological additive of the present invention shows no intercoat adhesion failures using the cross hatch test as compared with the Comparative Example 3 where Comparative X was used and are equal to the Comparative Example 2 where no rheological additive at all was added to the primer formulation. In the tape test, the rheological additive of the present invention shows excellent intercoat adhesion properties as compared to the Comparative Example 2.
 
Test 3
 
                                                         TABLE 5                   Spray Conditions                5° C.   23° C.   40° C.                        1. tin lid putting on   direct   direct   direct       2. tin lid putting on   After 3-4 hours   After 2 hours   After ½ hour       3. tin lid putting on   After 6-8 hours   After 4 hours   After 1½ hour       First recoating after   72 hours   48 hours   24 hours       Second recoating after   1 week   1 week   1 week                    
Panels were cured at 5°, 23°or 40° C. before overcoating (spraying at room temperature). Also the primer and the substrate were temperature controlled before the first spraying and the first recoating. Spray pressure: 4-5 bar, spray nozzle: 1.2 mm
 
     
       
         
               
             
               
               
               
               
             
               
               
               
               
             
               
             
               
               
               
               
             
               
             
               
               
               
               
             
               
               
             
           
               
                   
               
               
                 FORMULATION D 
               
               
                 SHORT OIL AIR DRYING ALKYD SYSTEM 
               
             
          
           
               
                   
                 Component 
                 Function 
                 Weight % 
               
               
                   
                   
               
             
          
           
               
                   
                 Mill-base: 
                   
                   
               
               
                   
                 Jägalyd FS 48, 55% 
                 Alkyd binder 
                 15.00 
               
               
                   
                 K21 (white spirit) 
                 Solvent 
                 2.00 
               
               
                   
                 Xylene 
                 Solvent 
                 2.00 
               
               
                   
                 Rheological additive 
                 Rheological additive 
                 1.00 
               
             
          
           
               
                 Predisperse at 16 m/s (4 cm tooth blade) for 5 minutes 
               
             
          
           
               
                   
                 Sojalecithin STA 
                 Wetting agent 
                 0.40 
               
               
                   
                 KRONOS 2190 
                 Titanium dioxide 
                 24.50 
               
             
          
           
               
                 Disperse at 18 m/s for 30 minutes (temperature is controlled) 
               
             
          
           
               
                   
                 Let down: 
                   
                   
               
               
                   
                 Jägalyd FS 48, 55% 
                 Alkyd binder 
                 48.00 
               
               
                   
                 Exkin 2 
                 Anti-skinning agent 
                 0.20 
               
               
                   
                 Byk 301 
                 Scratch resistance additive 
                 0.40 
               
               
                   
                 Jäger drier 3.3 
                 Drier 
                 2.00 
               
               
                   
                 K21 
                 Solvent 
                 2.50 
               
               
                   
                 Xylene 
                 Solvent 
                 2.00 
               
             
          
           
               
                 Mix at low speed for 5 minutes 
                   
               
               
                   
                 100.00 
               
               
                   
               
             
          
         
       
     
                                                                                                               TABLE 6                   Results in an air drying short oil alkyd paint       Rheological additive: 1.0%                 Brookfield RVT viscosities                        (mPa s) after 1 day            rpm   Hegman Grind   Sag (mm) 4 mm groove,            Example   10   20   50   100   after 30 min.   length of runners   T.I.                    Comparative   1200   1200   1160   1140   7.0A   132    1.05       Example 4       Comparative   6400   4800   3320   2600   7.0A   17   2.46       Example 5*       Inventive   6000   4600   3200   2580   6.5B   20   2.33       Example 1*       Inventive   7200   5200   3480   2680   2.5B   16   2.69       Example 4*       Inventive   5200   4000   2960   2400   3.5B   22   2.17       Example 5*       Inventive   4400   3600   2800   2320   2.0B   24   1.90       Example 6*       Inventive   5400   4200   2960   2400   2.0B   21   2.25       Example 7*       Inventive   7000   6750   6000   5500   6.5B   116†   1.27       Example 13       Inventive   8000   6750   5500   4900   4.5B    76†   1.63       Example 20       Inventive   11500   9250   7000   6000   3.0B    37†   1.92       Example 22       Inventive   13000   11000   8200   6750   4.0B    28†   1.93       Example 23       Inventive   16500   12500   9200   7550   6.5B    8†   2.19       Example 24               *Values after diluted with 5% xylene         †Sag 6 mm groove              
Discussion of Results: As may be seen from the data set forth above, the rheological additives of the present invention show high viscosity increase and excellent anti-sagging properties as compared to the comparative example containing no rheological additive. The inventive additives show comparable viscosity increase and anti-sag properties as compared to the comparative Example 5.
 
     SUMMARY OF THE PRECEDING EXAMPLES AND TESTS 
     The above results demonstrate the ability of the current invention to make paint and coating products without affecting intercoat adhesion as compared with prior art Comparative X. The above results also demonstrate that making the product in this manner does not detract from its effectiveness in thickening an organic based paint. 
     In this regard, the inventive rheological additives of this invention do not adversely affect intercoat adhesion properties of topcoats, which are subsequently applied to primers. The rheological additives of the present invention also provide acceptable and adequate increases in viscosity, improved sag resistance and suspending properties when incorporated in various coating systems. 
     The foregoing description and examples have been set forth merely to illustrate the invention and are not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.