CROSS REFERENCE TO REUTED APPLICATIONS

[0001] This application claims benefit of U.S. Provisional Applicatioπ No. 61/147,575 filed January 27, 2009.

BACKGROUND OF THE INVENTION Field of the Invention

[0002] The present invention relates to a method of producing a dspersion as well as to a coating that comprises the dispersion. Background Information

[0003] Over the past several years, there has been an effort to reduce atmospheric pollution caused by volatile solvents that are emitted during a painting process. However, it is oflen difficult to achieve high quality, smooth coaling finishes, such as are required in the automotive industry, without using organic solvents which contribute greatly to flow and leveling of a coating. Therefore, one of the goals of the coatings industry is to minimize the use of organic solvents by formulating waterbome coating compositions which provide a smooth, high gloss appearance, as well as good physical properties including, for example, resistance to add rain.

SUMMARY OF THE INVENTION

[0004] The present invention is directed to a method for producing a dispersion comprising: (a) reacting 0) a monomer comprising an ethylenlcally unsaturated double bond; (Ii) a carboxylic acid group-containing monomer; and (iii) a glycidyi ester compound to form a reaction product comprising a carboxylic acid group; and (b) reacting the reaction product of (a) with an amine compound; and wherein there is a molar excess of (ii) to (Ii); wherein steps (a) and (b) are conducted in a substantially solvent free environment and wherein the reaction product of (b) is not further reacted with a polyester polyol. The present invention is also directed to a coating composition comprising the dispersion. [0005] The present invention is also directed to a method for produdng an aqueous dispersion consisting essentially of: (a) reacting (i) a monomer comprising an ethylenically unsaturated double bond: (B) a carboxylic acid group-containing monomer; and (iii) a glyddyl ester compound to form a reaction product comprising a carboxylic acid group; (b) reacting the reaction product of (a) with an amine compound; and (c) dispersing the reaction product of (b) into water; wherein in step (a) there is a molar excess of (ii) to (iii) and a free radical polymerization initiator is used, and wherein steps (a) and (b) are conducted In a substantially solvent free environment and wherein the reaction product of (b) is not further reacted with a polyester polyol. The present invention is also directed to an aqueous coating composition comprising the dispersion.

DETAILED DESCRIPTION OF THE INVENTION

[0006] As used herein, unless otherwise expressly specified, all numbers such as those expressing values, ranges, amounts or percentages may be read as if prefaced by the word "about", even H the term does not expressly appear. Plural encompasses singular and vice versa. For example, although reference Is made herein to V monomer comprising an elhylentealy unsaturated double bond, "a" carboxylic acid group-containing monomer, "a" glycldyl ester compound, a combination (a pluralfy) ol these components can be used in the present invention.

10007] As used herein, TpiuraBty" means two or more.

[OOOβ] As used herein. Includes" and like terms means Including without Imitation."

[0009] When referring to any numerical range of values, such ranges are understood to include each and every number and/or fraction between the staled range minimum and maximum. For example, a range of "1 to 10" is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10.

[00101 As used herein, "molecular weight* means weight average molecular weight (Mw) as determined by Qei Permeation Chromatography.

[0011] As used herein, the term "cure* refers to a coating wherein any crossllnkable components of the composition are at least partially orosslinked. In certain embodiments, the crosslink density of the crosslinkable components (i.e., the degree of crosslinking) ranges from 5% to 100%, such as 35% to 65%, or, in some cases, 50% to 65% of complete crosslinWng. One skilled In the art will understand that the presence and degree of crosslinking, I.e., the crossBnk density, can be determined by a variety of methods, such as dynamic mechanical thermal analysis (DMTA) using a Polymer Laboratories MK III DMTA analyzer conducted under nlrogβn.

[0012] Reference to any monomer(s) herein refers generally to a monomer that can be polymerized with another poiymerizable component such as another monomer or polymer. Unless otherwise Indicated, it should be appreciated that once the monomer components react with one another to form a compound, the compound will comprise the residues of the monomer components.

Method _, tor Producing a Dispersion.

[0013] The present invention is dtocted to a method for producing a dispersion, such as an aqueous dispersion, which comprises a one stage reaction product that does not contain a polyester polyoi residue. In certain embodiments, the one stage reaction product is a one stage polymer. That is, all the monomers are combined and polymerized In a single step. In some embodiments, one or more of the steps in the method Is performed in a substantially solvent free environment. As used herein, a "substantially solvent free environment" means that trace or incidental amounts of organic solvent, such as ≤ 5 weight % or ≤ 3 weight % or ≤ 1 weight % based on the total weight of the reaction mixture, can be present.

[0014] The method begins by (a) reacting: (i) a monomer comprising an elhylenicaly unsaturated double bond; (B) a carboxyllc acid group-containing monomer, and (iii) a glycidyl ester compound to form a carboxylc add functional reaction product. A molar excess of (ii) to (iii) is used during this step. Accordingly, in certain embodiments, the molar ratio of (ii) the carboxylic add group-containing monomer when compared to (Ii) the glycidyl ester compound is 1.3:1 to 1.7:1 such as 1.5:1. Other ratios may also be suitable depending on the needs of the user.

[0015] Any suitable monomer comprising an ethylenically unsaturated double bond may be used as component (i), so long as it may be polymerized under the conditions described therein. Suitable monomers that may be used include, without limitation, (meth)acryiate, vinyl aromatic compounds (e.g. styrene, vinyl toluene), nitrite (e.g., (meth)acrylonitrile), vinyl and/or vlnylkleno halides (e.g., vinyl chloride, vinylidene fluoride), vinyl esters (e.g., vinyl acetate), or combinations thereof.

[0016] Suitable <meth)acrylatβ monomers include, without limitation, the C _I -CM aliphatic alkyl esters of (meth)acryflc add such as methyl(meth)acrylate, βthyl(meth)aorylate, propyl(meth)aorylate, N-butyl(meth)acrylate, t-butyi(meth)acrylate, 2- ethylhexyl(meth)acrylate, lsobomyl (meth)acrylate. glyddyl (meth)acrylate, dimethylamJnøethyl (melh)acryiate, N-butoxy methyl (meth)acrylamlde, lauryl (meth)acrylate, cyclohexyl (meth)acrylatβ. 3,3,5-trimethylcvclohexyl (meth)acrylate, hydroxy functional (meth)acrylates (e.g., hydroxyefrtyl (melh)acrylate, hydroxy butyl (melh)acrylate, hydroxy propyl (meth)acrylale), or combinations thereof.

[0017] Any suitable carboxylic acid group-containing monomer may be used as component (Ii) ₁ so long as it may be polymerized under the conditions described herein. Suitable monomers that may be used include, without Imitation, (meth)acrvilc add, maleic add and its corresponoϊng anhydride, ftaconic add, aconitic add, fumade add, alpha-halo acry ^β o acid, vinyl acetic add, beta-carboxymethyl (meth)acrylale, or combinations thereof.

[0018] Suitable monomers that may be used as component (III) the glycidyl ester compound Include, without limitation, the glyckJyf esters of carboxyllc acids such as VERSATIC ACIO 911 and CARDURA E, each of which is commercially available from Resolution Performance Products. [0019] A tree radical polymerization initiator iβ typicaly used to Initiate the reaction between components (I). P). and/or (IS). Suitable compounds that may be used as the free radical polymerization initiator include, without limitation, thermal initiators, photoinitialors, oxidation-reduction initiators, or combinations thereof. Examples of thermal initiators include, without limitation, azo compounds, peroxides, persulfates, or combinations thereof. Suitable persulfates include, without limitation, sodium pβrsutfate, ammonium persulfate, or combinations thereof. Oxidation-reduction initiators include, without limitation, persulfate- bisulfite systems, systems utilizing thermal initiators In combination with appropriate metal ions such as iron or copper, or combinations thereof.

[0020] Suitable azo compounds include, but are not Smiled to non-water-soluble azo compounds such as M'-azoblβcyctohexanβcaiboπitnTe, 2-2'-azobJsisobutyronltπϊβ, 2-2*- azobis(2-melhylbutyronitrite), 2-2*-azobis(proplonitrile), 2-2 ^> -azobi8(2,4-dimethytvalen>nitrtle), 2-2 ^> -azobis(valeronilrile), 2*{caibamoylazo)-l8Obutyronitrile and mixtures thereof; and water- soluble βzo compounds such as azobis tertiary afcyl compounds including, but not limited to, 4-4'-azobis(4-cyanovaleric acid), 2-2*-azobis(2-methy|propionamkSne)dihydrochlorlde. 2,2 ^* - azobis[2-mβUiyl-N-(2-hydroxyβthyl)prcpionamldβ], 4,4'-azobfs(4-cyanopentanoic add), 2.2 ¹ - azobl8(N,N'-dlmethylenel80butyramidine) ₁ 2,2'-azobis(2-amlolnopropane} ^hydrochloride, 2,2'-azobis(N,N'-dimethyleneisobutyramidlne) dhydrocNoride, or combinations thereof.

[0021] The reaction product of siep (a) will comprise acid functionality (e.g., carboxyHc add functionality). Additionally, depending on the monomers used in step (a), the reaction produot that is formed during step (a) may comprise a reactive functional group in addition to the carboxylkj add functional group. As used herein, the phrase "reactive functional group* also means hydroxy!, carbamate, epoxy, isooyanate, aceto acetate, amine, mercaptan, or combinations thereof.

[0022] Step (a) can be conducted via free radical polymerization techniques known in the art For example, in certain embodiments, step (a) is conducted at a temperature ≥ 100°C, such as 160*C, to drive the polymerization process. In other embodiments, step (a) is conducted at a temperature ≤ 20O ⁴ C. In some embodiments, the temperature can range between any combination of values, which were recited in the preceding sentences, inclusive of the recited values. For example, in certain embodiments, the temperature can range from 1S0°C to 170 ⁴ C or from 160°C to 180°C.

[0023] The reaction product of step (a) is then reacted with an amine compound (step (b)). In certain embodiments, step (b) is conducted at a temperature that is below the boding point temperature of the amine compound. For example, in some embodiments, step (b) is conducted at a temperature of ≤ 120°C, such as ≤ 80 ^β C. The amine compound that is added during this step is typically added in an amount suffident to provide a pH of 7 to 10 when the reaction product oi this stop te dispersed in water. Suitable amines that may be used in INs step include, without limitation, dimethylethanolamlne, ammonia, triethyl amine, diethyl propanol amine, or combinations thereof.

[0024] As stated above, the reaction product of step (a) nor the reaction product of step (b) Is not further reacted with a polyester poiyol. Therefore, the final reaction product does not contain a polyester poiyol residue.

[0025] Following step (b), the polymer can be dispersed in a water using techniques known in the art in order to form an aqueous dispersion. For example, water can be introduced into the reaction vessel containing the reaction product oi step (b) or the polymer can be added into another reactor or container that contains water. The water can contain other water dispersed components that can be added either prior to or alter the reaction product of step (b) Ie dispersed in the water.

Coating Composition

[0026] The dispersion described above can be incorporated into a coating composition, such as a waterbome coating composition, which can be used in a variety of coating applications. Accordingly, in one embodiment, the present invention is directed to a coating composition comprising the dispersion that was prepared by the method described above, in certain embedments, the coating composition can further comprise a crosslnking agent (curing agent) that is reactive with a reactive functional group on the reaction product of step (b) above. Suitable crossfinking agents include, without limitation, aminoplasts, polyisocyanates øndυdlng blocked isocyanates), polyepoxides, beta-riydroxyalkylamkfβs, polyadds, anhydrides, organometalHc acid-functional materials, poryamines, polyamides, cyclic carbonates, sβoxaneβ, or combinations thereof.

[0027] In certain embodiments, the croβsβnking agent comprises * 10% by weight of the total resin solids o< the coating composition. In other embodiments, the crosslinking agent comprises ≤ 45% by weight of the total resin solids of the coating composition. In certain embodiments, the total amount of crosslinking agent in the coating composition can range between any combination of values, which were recited in the preceding sentences, inclusive of the recited values. For example, in certain embodiments, the total amount of crosslinking agent can range from 25% by weight to 35% by weight, such as 28% by weight, of the total resin solids oi the coating composition.

[0028] The coating composition described herein may further comprise additional ingredients such as colorants. As used herein, the term "colorant" means any substance that Imparts color and/or other opacity and/or other visual effect to the composition. The colorant can be added to the coating In any suitable lorm, such as discrete particles, dispersions, solutions and/or flakes (e.g., aluminum flakes). A single colorant or a mixture of two or more colorants can be used In the coaling composition described herein.

[0029] Example colorants include pigments, dyes and tints, such as those used in the paint Industry and/or listed in the Dry Color Manufacturers Association (DCMA), as well as special effect compositions. A colorant may include, for example, a finely divided solid powder that is insoluble but wettable under the conditions of use. A colorant can be organic or inorganic and can be agglomerated or non-agglomerated. Colorants can be incorporated Into me coatings by use of a grind vehicle, such as an acrylic grind vehicle, the use of which will be familiar to one skMed in the art.

[0030] Example pigments and/or pigment compositions Include, but are not limited to, carbazole dloxazine crude pigment, azo, monoazo. cfisazo, naphthoi AS, salt type (lakes), benzbnidazolone, condensation, metal complex, isoindolimne, isoindoline and poiycycfic phthalocyaninβ, quinaorfdone, perylene, perlnone. cRketopyrrolo pyrrole, thioindigo, anthraquinone, indanthrone, anthrapyrimidine, flavanthrone, pyranthrone, anthanthrone, dloxazine, triarylcarbonium, quinophthalone pigments, diketo pyrrolo pyrrole red ("DPPBO red"), titanium dioxide, carbon black, or mixtures thereof. The terms "pigment" and "colored filer" can be used interchangeably.

[0031] Example dyes Include, but are not limited to, those that are solvent and/or aqueous based such as phthalo green or blue, iron oxide, bismuth vanadate, anthraquinone, perylene, aluminum and qulnacridone.

[0032] Example tints include, but are not limited to, pigments dispersed in water-based or water miscible carriers such as AQUA-CHEM 896 commerciafy available from Degussa, Inc., CHARISMA COLORANTS and MAXITONER INDUSTRIAL COLORANTS commerdaly available from Accurate Dispersions division of Eastman Chemical, Inc.

[0033] As noted above, the colorant can be In the form of a dispersion including, but not Brnltod to, a nanopariicle dispersion. Nanoparlicle dispersions can include one or more highly dispersed nanoparttøβ colorants and/or colorant particles that produce a desired visible color and/or opacity and/or visual effect. Nanopartfcle dispersions can include colorants such as pigments or dyes having a particle size of less than f 50 nm, such as less than 70 nm, or less than 90 nm. Nanoparticles can be produced by miUng stock organic or inorganic pigments with grinding media having a particle size oi less than 0.5 mm. Example nanopariicle dispersions and methods for making them are identified in U.S. Patent No. 6,875,800. Nanopartide dispersions can also be produced by crystallization, precipitation, gas phase condensation, and chemical attrition (i.e., partial dissolution). In order to minimize rβ-agglomeratlon ol nanoparticles within the coating, a dispersion of resin-coated nanoparticles can be used. As used herein, a "dispersion of resin-coated nanoparticles" refers to a continuous phase in which discreet "composite micropaticles ", which comprise a nanoparticle and a resin coating on the nanoparticle, is dispersed. Example dispersions of resin-coated nanoparticles and methods (or making them are identified in United States Patent Application Publication 2005-0287348. filed June 24, 2004, U.S. Provisional Application No.60/482,167, filed June 24, 2003. and United States Patent Application Serial No. 11/337,062, fled January 20.2006.

[0034] Example special effect compositions that may be used include pigments and/or compositions that produce one or more appearance effects such as reflectance, peariescence, metallic sheen, phosphorescence, fluorescence, photochrornism, photosensitivity, thermochromism. goniochromism and/or color-change. Additional special eflect compositions can provide other perceptible properties, such as opacity or texture. In a non-limiting embodiment, special effect compositions can produce a color shift, such that the color of the coaling changes when the coating Is viewed at different angles. Example color elfect compositions are identified in U.S. Patent No. 6,894,086. Additional color effect compositions can Include transparent coated mica and/or synthetic mica, coated silica, coated alumina, a transparent liquid crystal pigment, a liquid crystal coating, and/or any composition wherein interference results from a refractive index differential within the material and not because of the refractive index differential between the surface of the material and the air.

[0035] In certain non-limiting embodiments, a photosensitive composition and/or photochromio composition, which reversbly alters Its color when exposed to one or more light sources, can be used in the coating composition described herein. Photochromic and/or photosensitive compositions can be activated by exposure to radiation of a specified wavelength. When the composition becomes ex cited, the molecular structure is changed and the altered structure exhibits a new color that is different from the original color of the composition. When the exposure to radiation is removed, the photochromic and/or photosensitive composition can return to a state of rest, in which the original color of the composition returns. In one non-limiting embodiment, the photochromic and/or photosensitive composition can be colorless in a non-excited state and exhibit a color in an excited state. Full color-change can appear within milliseconds to several minutes, such as from 20 seconds to 60 seconds. Example photochromic and/or photosensitive compositions include pholochromic dyes.

[0036] In a non-limiting embodiment, the photosensitive composition and/or photochromio composition can be associated with and/or at least partially bound to, such as by covalent bonding, a polymer and/or polymeric materials of a polymerizable component. In contrast to some coatings in which the photosensitive composition may migrate out of the coating and cryβtaizβ into the substrate, the photosensitive composition and/or photochrome composition associated with and/or at least partially bound to a polymer and/or polymerizable component in accordance with a non-limiting embodiment ot the present invention, have minimal migration out of (he coating. Example photosensitive compositions and/or photochrome compositions and methods for making them are identified in U.S. Application Serial No. 10/892,919. fled July 16, 2004.

[0037] In general, the colorant can be present in any amount sufficient to impart the desired visual and/or color effect. The colorant may comprise from 1 to 65 weight percent of the present compositions, such as from 3 to 40 weight percent or 5 to 35 weight percent with weight percent based on the total weight of the compositions.

[0038] The coating compositions can comprise other optional materials well known in the art of formulated surface coatings, such as plasticizers, anti-oxktentβ, hindered amine light stablizers, UV Rght absorbers and stabilizers, surfactants, flow control agents, thixotropic agents such as bentonfte clay, pigments, flers, catalysts, including phosphoric adds and other customary auxiliaries.

Substrate with a Coaling System

[0039] The coating composition descrbed above may be appfiθd alone or as part of a coating system that can be deposited onto a number of different substrates. The coating system typically comprises a number of coating layers. A coating layer is typically formed when a coating composition that is deposited onto the substrate is substantialy cured by methods known in the art (e.g., by thermal heating). It is noted that the coating composition described above can be used In one or more of the coating layers described in the lolowing paragraphs.

[0040] Suitable substrates that can be coated with the coating composition include, without Omitalion, metal substrates, metal alloy substrates, substrates that have been metallized, such as nickel plated plastic and/or plastic substrates. In some embodiments, the metal or metal alloy can be aluminum and/or steel. For example, the steel substrate could be cold roled steel, electrogalvanized steel, and/or hot dipped galvanized steel. Moreover, in some embodiments, the substrate may comprise a portion of a vehicle such as a vehicular body (e.g., without limitation, door, body panel, trunk deck Id, roof panel, hood, and/or roof) and/or a vehicular frame. As used herein, "vehicle" or variations thereof includes, but is not limited to, civilian, commercial, and miltary land vehicles such as cars, motorcycles, and trucks. K will also be understood that, in some embodiments, the substrate may be pretreated with a pretreatment solution, such as a zinc phosphate solution as described in U.S. Pat. Nos. 4,793,867 and 5,580,989 or not pretreated with a pretreatment solution. [0041] In a conventional coating system used In the automotive industry, a pretreated substrate is coated with an electrodepoβitable coaling composition. After the eiectrodepositable coating composition is cured, a primer-surfacer coating composition is applied onto a least a portion of the electrodβpositabie coating composition. The primer- surfacer coaling composition is typically applied to the electrodepoβitaJMe coating layer and cured prior to a subsequent coating composition being applied over the primer-surfacer coating composition. However, K should be noted that In some embodiments, the substrate is not coated with an etectrodepoδltable coating composition. Accordingly, in these embodiments, the primer-surfacer coating composition is applied directly onto the substrate.

[0042] The primer-surfacer layer that results from the primer-surfacer coating composition serves to enhance chip resistance of subsequently applied coating layers (e.g., color imparting coating composition and/or substantially clear coating composition) as well as to aid in the appearance of the subsequently applied layers. As used herein, ^• primer-surfacer" refers to a primer composition for use under a subsequently applied coating composition, and includes such materials as thermoplastic and/or crossUnking {o.g., thermosetting) film- forming resins generally known In the art of organic coating compositions. Suitable primers and primer-suriacβr coating compositions include spray applied primers, as are known to those skilled in the art. Examples of suitable primers Include several available from PPQ Industries, Inc., Pittsburgh, Pa., as DPX-1791. DPX- 1804, DSPX-J 537, GPXH-5379, OPP- 2645, PCV-70118, and 1177-225A. Another suitable primer-surfacer coating composition that can be utlized in the present invention Is the primer-surfacer described In U.S. Pat Application No. 11/773,462.

[0043] It should be noted that in some embodiments, the primer-surfacer coating composition is not used in the coaling system. Therefore, a color imparting basecoat coating composition can be applied drectly onto the cured eiectrodepositable coating composition.

[0044] In some embodiments, a color imparting coaling composition (hereinafter, "basecoat") is deposited onto at least a portion of the primer surfacer coating layer (if present). Any basecoat coating composition known in the art may be used in the present Invention. It should be noted that these basecoat coating compositions typically comprise a colorant.

[004S] In certain embodiments, a substantially clear coating composition (hereinafter, "dearcoat") is deposited onto at least a portion of the basecoat coating layer. As used herein, a "substantially clear" coating layer is substantially transparent and not opaque. In certain embodiments, the substantialy dear coating composition can comprise a colorant but not in an amount such as to render the dear coating composition opaque (not substantially transparent) after ft haβ been cured. Any dearcoat coaling composition known in the art may be used in the present invention. For example, the dearcoat coating composition that is described in U.S. Patent Nos. 5,989,642, 6.245,855, 637,519, and 7,005,472 can be used in the coating system. In certain embodiments, the substantially clear coating composition can also comprise a particle, such as a sMca particle, that is dispersed in the dearcoat coaling composition (such as at the surface of the dearcoat coating composition after curing). In some embodiments, the coating composition comprising the polymer described herein can be used as the dβarooat coating composition. 10046] One or more of the coaiinø compositions described in the preceding paragraphs can comprise the colorants and the other optional materials (which are Known In the art of formulated surface coatings) described above.

[0047] It will be further appreciated that one or more of the coating compositions that form the various coating layers described herein can be either "one component" ('1K"), "two component" C2KT). or even multi-component compositions. A IK composition wil be understood as referring to a composition wherein aβ of the coating components are maintained in the same container after manufacture, during storage, etc. A 2K composition or mufti-component composition will be understood as referring to a composition wherein various components are maintained separately until just prior to application. A 1K or 2K coating composition can be applied to a substrata and cured by any conventional means, such as by heating, forced air, and the like.

[0048] The ooating compositions that form the various coating layers described herein can be deposited or applied onto the substrate using any technique that is known in the art. For example, the coating compositions can be applied to the substrate by any of a variety of methods including, without limitation, spraying, brushing, dipping, andtor roll coating, among other methods. When a plυraBty of coating compositions are applied onto a substrate, it should be noted that one coating composition may be applied onto at least a portion of an underlying coating composition either after the underlying coating composition has been cured or prior to the underlying coating composition being cured. If the coating composition is applied onto an underlying coating composition that has not been cured, one or more of the uncured coating compositions may be cured simultaneously.

[0049] The coating compositions may be cured using any technique known in the art such as, without limitation, thermal energy, infrared, ionizing or actinic radiation, or by any combination thereof. In certain embodiments, the curing operation can be carried out at temperatures * 1O"C. In other embodiments, the curing operation can be carried out at temperature s 246*C. In certain embodiments, the curing operation can carried out at temperatures ranging between any combination of values, which were recited in the preceding sentences, inclusive of the recited values. For example, the curing operation can be carried out at temperatures ranging from 120*C - IS0°C. It should be noted, however, that lower or higher temperatures may be used as necessary to activate the curing mechanisms.

[0050] In certain embedments, the coating compositions described herein are a low temperature, moisture curable coating compositions. As used herein, the term low temperature, moisture curable" refers to coating compositions that, following application to a substrate, are capable of curing in the presence ol ambient air, the air having a relative humidity of 10 % to 100 %, such as 25 % to 80 %, and a temperature in the range of -10O to 120 ⁴ C ₁ such as 6°C to 80*C, in some cases 10°C to 60 "C and, in yet other cases, 15 ⁴ C to

40 ^« C.

[005J] The dry fflm thickness of the coating layers described herein can range from 0.1 micron to 500 microns. In other embedments, the dry film thickness can be ≤ 125 microns, such as s 80 microns. For example, the dry film thickness can range from 15 microns to 60 microns.

[0052] While specific embodments of the Invention have been described in detail, it will be appreciated by those skilled In the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the dsdosure. Accordingly, the particular arrangements disclosed are meant to be Wustratfve only and not limiting as to the scope of the invention which Ia to be given the full breadth of the claims appended and any and all equivalents thereof.

EXAMPLES

[0053] Example 1

This example demonstrates the synthesis of the stable aqueous dispersion of a combination of carboxylic add containing acrylic polymer pofyof of the present invention.

[0054] The synthesis uses the Ingredients shown in Table 1.

Table 1

[0055] Charge 1 was added to a reaction vessel equipped with a reflux condenser and nitrogen blanket and heated to 160°C. Charge 3 was added to the reaction vessel over a four hour period. Beginning at the same time as the charge 3, charge 2 was added to the reaction vessel over a 4.5 hour (h) period, folowed by their respective rinses. The resulting product continued to be mixed In the vessel at 160°C tor an hour. The product was cooled to 120°C and charge 4 was added over a 30 minute period of time. Charge 5 was pre-heated to 70°C and added to the vessel over a 30 minute period. The product was mixed for one hour at 100°C and decanted. The resulting product had total solids of 38.3 weight percent (1 -hour at 110°C) ₁ pH of 8.6 and viscosity of 44cps (Brookfield. RVT spindle #1.30 rpm at 22.3°C).

Coatlng Examples

[0056] Coating Example 1:

[0057] The two components are mixed by addition of the B-pack into the A-Pack under moderate stirring using a lab stirrer. Stirring time is between 30-60 seconds (s), depend on the amount of paint. The two components can also be mixed by using a KENICS static mixer.

[0059] The clearcoat coatings in Table 2 were appied by hand or automatic electrostatic technique over a commercial waterbome basecoat which had been dehydrated for 10 minutes at 80°C. The clearcoat compositions were flashed for 8-12 minutes at ambient temperature, dehydrated for 8-12 minutes at 50-80°C and then baked for thirty minutes at 140°C. The results of evaluations of the coated panels for appearance are summarized in Table 2 above.

[0060] The cured coatings gave on different baseooats systems good scratch and chemical resistance.

[0062] Coated panels were subjected to scratch testing by linearly scratching the coated surface with a weighted abrasive paper for ten double rubs using an Atlas AATCC Scratch Tester, Model CM-5, available from Atlas Electrical Devices Company of Chicago, Illinois. The abrasive paper used was 3M 281 Q WETORDRY™ PRODUCTION™ 2 micron and 9 micron polishing paper sheets, which are commercially available from 3M Company of St. Paul, Minnesota. Panels were then rinsed with tap water and carefully patted dry with a paper towel. The 20* gloss was measured on the scratched area of each test panel.