HK1141547B

HK1141547B - Cationic electrodepositable coatings comprising rosin

Info

Publication number: HK1141547B
Application number: HK10107986.9A
Authority: HK
Inventors: D‧R‧芬; G‧J‧麦克拉姆
Original assignee: Ppg工业俄亥俄公司
Priority date: 2007-07-20
Filing date: 2008-06-24
Publication date: 2016-03-24

Description

Cationic electrodepositable coating comprising rosin

Technical Field

The present invention generally relates to cationic electrodepositable coatings comprising rosin, wherein the rosin forms part of the cationic resin backbone.

Background

The prices of the feedstocks used in many manufacturing processes continue to rise, particularly those feedstocks whose prices rise or fall with the price of petroleum. Because of this, and because of the predicted depletion of oil reserves, feedstocks derived from renewable or alternative resources may be desirable. The increased demand for environmentally friendly products, along with the uncertainty of the volatile and volatile (volatile) petrochemical market, has prompted the development of feedstocks from renewable and/or inexpensive resources.

Summary of The Invention

The present invention relates to cationic electrodepositable coatings comprising rosin, wherein the rosin forms part of the cationic resin backbone.

Detailed Description

The present invention relates to cationic electrodepositable coatings or "electrophoretic paints" (ecoats) comprising rosin. The rosin forms part of the cationic resin backbone.

It will be understood that rosin actually comprises a mixture of compounds in which rosin acid is often predominant (i.e., more rosin acid than any other component). Rosin is commercially available as, for example, gum rosin, wood rosin, and tall oil rosin. Rosin acid can be used in its natural form according to the present invention or it can be purified by techniques known to those skilled in the art. In its natural form as rosin or abietic acid, abietic acid may exist together with isomeric forms such as pimaric (pimaritype) resin acid and levopimaric (levopimaric acid). Oleoresin material may also be present, as may dihydroabietic acid and dehydroabietic acid. Since rosin is a complex mixture of fused ring monocarboxylic acids of predominantly 20 carbon atoms and small amounts of non-acidic components in which the resin acid molecules have double bonds and carboxylic acid groups, it is possible to use derivatives which retain the carboxylic acid groups. One suitable example of a rosin that can be used is SYLVAROS NCY, tall oil rosin available from Arizona Chemical, and Brazilian gum rosin available from Gehring-Montgomery.

As mentioned above, rosin forms part of the backbone of the cationic resin. That is, the components in the rosin or moieties on the rosin are modified so that they can polymerize with the other components of the coating and thus, during the preparation of the cationic resin. Thus, the rosin forms part of the backbone of the cationic resin. Therefore, the present invention is different from the invention in which rosin is used as an additive; when used as an additive, the rosin is not modified and does not react into the backbone of the coating.

As noted above, the rosin is modified or altered such that it will form part of the cationic backbone. These modified rosins are sometimes referred to herein as rosin adducts. Thus, "rosin" is intended to include rosin or any compound comprising rosin, or a rosin residue. In certain embodiments, the rosin is reacted with a dienophile comprising a carboxyl and/or anhydride group and then reacted with an epoxy resin. More specifically, rosin is reacted with a dienophile containing carboxyl and/or anhydride groups. Particularly suitable dienophiles include α, β -ethylenically unsaturated monocarboxylic or dicarboxylic acids or anhydrides such as fumaric acid, maleic acid, acrylic acid, methacrylic acid, itaconic acid, citraconic acid and maleic anhydride. Any other dienophile containing a carboxylic acid group may also be used.

The rosin and dienophile can be reacted in a Diels-Alder (Diels Alder) reaction under conditions well known in the art, for example, between the melting point of the rosin and the boiling point of the dienophile. The reaction may be carried out at elevated pressure in order to increase the boiling point of the dienophile. The DielsAlder reaction between rosin and a dienophile containing one or more carboxyl and/or anhydride groups is described, for example, in the following: polymer from Renewable Resources-13, Polymer from Rosin Acrylic Acid adapter, Roy, Kundu and Maiti, Eur. Polymer.J., 26(4), 471, 1990; and Diels-Alder polymers from research Acids, Mustata and Bicu, Journal of Polymer engineering, 25(3), 217, 2005, both of which are incorporated herein by reference. This reaction will produce a carboxylated Diels Alder adduct of rosin ("rosin adduct"). It will be appreciated that the rosin adduct will have an average of more than one carboxylic acid functional group per molecule. In certain embodiments, the rosin adduct has two carboxylic acid functional groups, one from the rosin and one from the dienophile. The number of carboxylic acid groups per molecule of rosin adduct can be controlled by varying the number of carboxylic acid groups per molecule of dienophile and/or by varying the ratio of rosin to dienophile. The use of dienophiles having one carboxylic acid group per molecule is particularly suitable. The molar ratio of abietic acid groups to dienophiles may be from 1: 0.25 to 1: 2, for example from 1: 0.5 to 1: 1.1 or from 1: 0.8 to 1: 1. When the rosin adduct contains more than two carboxylic acid and/or anhydride functional groups, some of the carboxylic acid and/or anhydride functional groups may be removed by modifying the rosin adduct with a compound having a functional group reactive with the carboxylic acid/anhydride, such as an epoxy group or a hydroxyl group. Examples of such modifying compounds include CARDURA E10 (glycidyl esters of tertiary carboxylic acids, from Hexion specialty Chemicals), propylene oxide, or octanol. The rosin may constitute 95 to 40 wt%, for example 90 to 70 wt%, of the total solids weight of the rosin adduct.

Rosin can also react with linker molecules. As used herein, a "linker molecule" is any multifunctional molecule (i.e., two or more functional groups and/or functional sites) that will react with rosin in a manner such that the rosin retains acid functionality. In certain embodiments, the linker molecule is not a dienophile, such as a compound that will undergo a Diels Alder reaction with rosin. Since the linker molecule has at least two functional groups and/or functional sites, it can react with at least two rosin molecules. This results in at least two rosin molecules being joined by reaction with the linker molecule ("rosin adduct").

Suitable linker molecules include, for example, formaldehyde or glyoxal. The reaction between rosin and dienophile may be carried out under any suitable conditions, such as those described in the following documents incorporated herein by reference: "Study of the Condensation Products of Abetic Acid with formaldehydes", Bicu and Mustata, die Angew. Makromol., 213, 169, 1993. The rosin adduct will comprise a molecule having at least two carboxylic acid functional groups attached to a linker molecule, one carboxylic acid functional group from each rosin molecule. The rosin may comprise 50 to 99.9 wt%, for example 80 to 98 wt% of the total solids weight of the rosin adduct.

Rosin adducts, such as those formed by the reaction of rosin with a dienophile or linker molecule, are then reacted with an epoxy resin. Alternatively, it will be understood that rosin having one or more epoxy-reactive functional groups may be reacted directly with an epoxy resin. In certain embodiments, particularly those in which the rosin is reacted directly with an epoxy resin, the epoxy resin has at least two epoxy functional groups. A portion of the epoxy functionality will react with one of the rosin adduct or the carboxylic acid functionality on the rosin itself to form the modified epoxy resin of the present invention and a portion of the epoxy functionality will remain unreacted. The reaction product of rosin and/or rosin adducts with epoxy resins is sometimes referred to herein as a modified epoxy or modified epoxy resin.

Suitable epoxy resins include, but are not limited to, those having a 1, 2-epoxy equivalent weight greater than 1, such as at least 2; that is, a polyepoxide having an average of two epoxide groups per molecule. Typically, the epoxide equivalent weight of the polyepoxide can be 100-2000, such as 180-1200 or 180-500. The epoxy resin may be saturated or unsaturated, cyclic or acyclic, aliphatic, cycloaliphatic, aromatic or heterocyclic. It may contain substituents such as halogen, hydroxyl and/or ether groups. Particularly suitable polyepoxides are polyglycidyl ethers of polyhydric alcohols, for example cyclic polyhydric alcohols, for example polyglycidyl ethers of polyhydric phenols such as bisphenol A. These polyepoxides can be prepared by etherification of a polyhydric phenol with an epihalohydrin or dihalopropanol (dihalohydrin), such as epichlorohydrin or dichloropropanol (dichlorhydramin), in the presence of a base. Other cyclic polyols may also be used to prepare polyglycidyl ethers of cyclic polyols. Examples of the other cyclic polyols include alicyclic polyols, particularly alicyclic polyols such as 1, 2-cyclohexanediol and 1, 2-bis (hydroxymethyl) cyclohexane. Epoxy group-containing acrylic polymers may also be used. These polymers typically have an epoxy equivalent weight of about 750-. The modified epoxy resin is epoxy functional in that a portion of the epoxy functional groups remain unreacted. As used herein, "epoxy-functional" and similar terms refer to a compound or polymer having at least one unreacted epoxy group. This epoxy group can be reacted with, for example, a carboxylic acid to form an ester bond or with a primary amine to form a secondary amine or with a secondary amine to form a tertiary amine. In this way, the modified epoxy resins used according to the invention can be crosslinked or can form at least part of a coating.

The modified epoxy resin may be prepared by any method known in the art, for example, the following: reacting together an epoxy resin and a rosin and/or rosin adduct, neat or in the presence of an inert organic solvent; any suitable solvent may be used, for example ketones, including methyl isobutyl ketone and methyl amyl ketone; aromatic compounds such as toluene and/or xylene; and/or glycol ethers such as dimethyl ether of diethylene glycol. The reaction is typically carried out at a temperature of 80 ℃ to 160 ℃ for 30 to 180 minutes until an epoxy group-containing resin reaction product is obtained. Alternatively, the reaction may be carried out in a continuous reactor and may be carried out at a temperature of 140 ℃ to 280 ℃ for 1 to 20 minutes. The equivalent ratio of reactants, i.e.epoxide groups to carboxylic acid groups, is typically in the range 1.00: 0.20 to 1.00: 0.80.

It will be appreciated that the reaction between the rosin and/or rosin adduct and the epoxy resin may actually produce a mixture comprising the reaction product of: a rosin adduct, an epoxy resin, and two epoxy groups containing molecule, a rosin adduct, an epoxy resin, and one epoxy group containing molecule, an unreacted epoxy resin, and/or an unreacted rosin adduct. The use of excess epoxy resin in the reaction minimizes, if not eliminates, the presence of unreacted rosin and/or rosin adducts in the reaction mixture. Conditions may be controlled to produce a reaction mixture that is predominantly a molecule containing rosin and/or rosin adduct, epoxy resin, and two epoxy groups.

It will be appreciated that when a modified epoxy is formed, the epoxy ring will open and a hydroxyl group will be formed. The hydroxyl group may be further reacted with a compound having one or more hydroxyl-reactive groups. A hydroxyl-reactive group is a group that reacts with a hydroxyl group. This increases the molecular weight of the modified epoxy resin. Increased molecular weight may result in improved properties, such as improved solvent resistance, corrosion resistance, hardness, and/or stability. The compound having one or more hydroxyl-reactive groups may be a polyisocyanate. Suitable polyisocyanates include, but are not limited to, aliphatic diisocyanates such as hexamethylene diisocyanate and isophorone diisocyanate and aromatic diisocyanates such as toluene diisocyanate and 4, 4' -diphenylmethane diisocyanate. Examples of other suitable polyisocyanates include, but are not limited to, uretdione (uretdione), isocyanurate trimer and allophanate of diisocyanates. Suitable polyisocyanates are well known in the art and are widely available. For example, suitable polyisocyanates are disclosed in U.S. Pat. No.6,316,119 at column 6, lines 19-36, incorporated herein by reference. Examples of commercially available polyisocyanates include LUPRANATEM20S sold by BASF Corporation, DESMODUR N3390 sold by Bayer Corporation, and TOLONATE HDT90 sold by Rhodia Organics. When rosin is reacted directly with epoxy, reaction with compounds having one or more hydroxyl-reactive groups is particularly suitable.

"coating" of the present invention will be generally understood to be a composition that, when cured, is capable of forming a substantially continuous film that forms a surface layer that provides a decorative and/or protective function, and in certain embodiments the film is not tacky (tack) or not tacky (tack) when cured. Thus, in certain embodiments, the coating of the present invention will not include a binder. In certain other embodiments, the coating of the present invention will not include a layered material.

It will be understood that rosin as described herein will form part of the cationic backbone when used in the coating of the present invention. That is, the rosin and/or its derivatives will be incorporated into the resin backbone, which in turn will react with a curing or crosslinking agent to form a coating. Those skilled in the art will appreciate that cured coatings in which rosin is used as a solvent, chain transfer agent, or tackifier or other additive will have a relatively low rosin content therein, unlike certain embodiments of the present invention. Thus, the rosin can comprise 5 to 75 weight percent, such as 20 to 60 weight percent, based on the total solids weight of the coating. In some embodiments, the coating comprises at least 20 wt%, such as at least 30 wt% rosin, the weight percent based on the total solids weight of the coating.

In certain embodiments, one or more additional film-forming resins are also used in the coating. For example, the coating composition may comprise any of a wide variety of thermoplastic and/or thermosetting compositions known in the art.

Thermosetting or curable coating compositions typically comprise a film-forming polymer or resin having functional groups reactive with itself or with a crosslinker. The film-forming resin may be selected from, for example, epoxy resins, acrylic polymers, polyester polymers, polyurethane polymers, polyamide polymers, polyether polymers, bisphenol a based epoxy polymers, polysiloxane polymers, copolymers thereof, and mixtures thereof. In certain particularly suitable embodiments, the cationic resin backbone comprises an aromatic-based or cyclic-based epoxy, such as a bisphenol a-based epoxy. "aromatic or cyclic based epoxy" refers to a compound containing an aromatic or cyclic moiety as well as an epoxy moiety. In general, these polymers may be any of these types of polymers made by any method known to those skilled in the art. These polymers may be solvent based or water dispersible, emulsifiable, or have limited water solubility. The functional groups on the film-forming resin may be selected from any of a number of reactive functional groups including, for example, carboxylic acid groups, amine groups, epoxide groups, hydroxyl groups, thiol groups (thiol groups), carbamate groups, amide groups, urea groups, isocyanate groups (including blocked isocyanate groups and trialkyl carbamoyl triazines), thiol groups (mercaptane groups), anhydride groups, acetoacetate acrylates (acetoacetate acrylates), isocyanate dimers (uretdiones), and combinations thereof. In certain embodiments, the acrylic resin is not the primary film former; that is, the resin that constitutes the predominant (i.e., more than any other) component of the resin is not an acrylic resin. Certain other embodiments are substantially free of acrylic resin. By "substantially free of acrylic resin" is meant that only trace amounts of acrylic resin, if any, are present, e.g., less than 5 wt%, 2 wt%, or 1 wt%.

Thermosetting coating compositions typically comprise a crosslinking agent, which may be selected from, for example, aminoplasts, polyisocyanates including blocked isocyanates, polyepoxides, beta-hydroxyalkylamides, polyacids, anhydrides, organometallic acid functional materials, polyamines, polyamides, and mixtures of any of the foregoing. In certain embodiments, the modified epoxy resin may be self-crosslinking. Self-crosslinking means that the reaction product contains functional groups capable of reacting with itself, such as alkoxysilane groups, or that the reaction product contains co-reactive functional groups, such as hydroxyl groups and blocked isocyanate groups. In certain embodiments, the blocked isocyanate groups may be introduced into the modified epoxy resin by reacting residual epoxy groups with the reaction product of a primary and secondary amine group-containing polyamine and an acrylic carbonate, as described in WO2006110515, incorporated herein by reference.

As noted above, the coatings of the present invention are electrodepositable and contain cationic salt groups. Thus, the modified epoxy and any other film-forming resin should be capable of being converted to cationic salt groups, or be reactive to another coating component capable of being converted to cationic salt groups. For example, the modified epoxy can have an epoxy functional group that can be converted to a cationic salt group. Cationic salt groups can be introduced by any means known in the art, for example by reacting an epoxy group-containing reaction product of the type described above with a suitable salt-forming compound. For example, sulfonium salt groups can be introduced by reacting sulfides in the presence of acids, as described in U.S. patents 3,959,106 and 4,715,898, incorporated herein by reference; the amine salt group may be derived from the reaction product of an epoxide function with a compound containing a primary or secondary amine group such as: methylamine, diethanolamine, ammonia, diisopropanolamine, N-methylethanolamine, diethylenetriamine, dipropylenetriamine, dihexamethylenetriamine, ketodiimine of diethylenetriamine (diketimine), ketodiimine of dipropylenetriamine, ketodiimine of dihexamethylenetriamine, and mixtures thereof. The cationic salt groups may be at least partially neutralized with an acid. Suitable acids include organic and inorganic acids such as formic acid, acetic acid, lactic acid, phosphoric acid, dimethylolpropionic acid and sulfamic acid. Mixtures of acids may be used. The resin may contain primary, secondary and/or tertiary amino groups.

It will be appreciated that in formulating the electrodepositable coating composition of the present invention, the modified epoxy, such as in the form described above, can be dispersed in a dispersing medium. The dispersion medium may be water. The dispersing step can be accomplished by combining the neutralized or partially neutralized modified epoxy with a dispersing medium. Neutralization and dispersion can be accomplished in one step by combining the modified epoxy and the dispersing medium. The above-mentioned reaction product may be added to the dispersion medium or the dispersion medium may be added to the reaction product (or a salt thereof). In certain embodiments, the pH of the dispersion is from 4 to 9. The dispersion may be formed at a solids level suitable for final coating, for example 5-15 wt%, or it may be formed at a higher solids content, for example 20-45 wt%, to minimize the weight and volume of material that needs to be stored and/or transported. The dispersion can then be adjusted to a solids level suitable for coating prior to use. Alternatively, the resin, optionally blended with a crosslinker, may be stored and transported as an organic solution and dispersed shortly before use. Suitable conditions for forming the stable dispersions described above include those described in the examples.

The rosin-containing cationic salt resins of the present invention can then be used in electrodeposition paints as can any other cationic salt known in the art. The rosin-containing cationic salt can comprise 10 to 90 wt%, for example 10 to 60 wt% of the electrodeposition paint. In certain embodiments, the electrophoretic paint may further comprise one or more other resins typically used in electrodepositable coatings. Examples include cationic acrylic resins, such as those derived from epoxy-functional acrylic resins, or the film-forming resins described above. In certain embodiments of the invention, the coating specifically excludes rubbers, such as olefin or modified olefin rubbers.

The coating composition may also include a solvent. Suitable solvents include water, organic solvents and/or mixtures thereof. Suitable solvents include glycols, glycol ether alcohols, ketones, aromatics such as xylene and toluene, acetates, mineral spirits, naphtha and/or mixtures thereof. "acetate" includes glycol ether acetates.

If desired, the coating composition may contain other optional materials well known in the art of formulating coatings, such as plasticizers, antioxidants, hindered amine light stabilizers, UV light absorbers and stabilizers, surfactants, flow control agents, thixotropic agents, colorants, fillers, organic cosolvents, reactive diluents, catalysts, and other conventional adjuvants.

As used herein, "colorant" and like terms refer to any substance that imparts color and/or other opacity and/or other visual effect to the composition. The colorant may be added to the coating in any suitable form, such as discrete particles, dispersions, solutions, and/or flakes. A single colorant or a mixture of two or more colorants can be used in the coating of the present invention.

Exemplary colorants include pigments, dyes, and tints, such as those used in the coatings industry and/or listed in the Dry Color Manufacturers Association (DCMA), as well as special effect compositions. The colorant may comprise, for example, a finely divided solid powder that is insoluble but wettable under the conditions of use. The colorant may be organic or inorganic and may be aggregated or non-aggregated. The colorant can be incorporated by utilizing a grind vehicle, such as an acrylic grind vehicle, the use of which is well known to those skilled in the art.

Exemplary pigments and/or pigment compositions include, but are not limited to, carbazole dioxazine crude pigment, azo, monoazo, disazo, naphthol AS, salts (lakes), benzimidazolone, metal complex, isoindolinone, isoindoline and polycyclic phthalocyanine, quinacridone, perylene, perinone, diketopyrrolopyrrole, thioindigo, anthraquinone, indanthrone, anthrapyrimidine, flavanthrone, pyranthrone, anthanthrone, dioxazine, triarylcarbonium, quinophthalone pigment, diketopyrrolopyrrole red ("DPPBO red"), titanium dioxide, carbon black, carbon fiber, graphite, other conductive pigments and/or fillers, and mixtures thereof. The terms "pigment" and "colored filler" may be used interchangeably.

Exemplary dyes include, but are not limited to, those that are solvent-based and/or water-based, such as phthalocyanine green or blue, iron oxide, bismuth vanadate, anthraquinone, perylene, aluminum, and quinacridone.

Exemplary tints include, but are not limited to, pigments dispersed in an aqueous-based or water-miscible carrier such as AQUA-CHEM 896 available from Degussa inc, CHARISMA COLORANTS and maxitorer INDUSTRIAL COLORANTS available from Accurate Dispersions department of eastman chemical, inc.

As noted above, the colorant can be in the form of a dispersion, including but not limited to in the form of a nanoparticle dispersion. Nanoparticle dispersions can include one or more highly dispersed nanoparticle colorants and/or colorant particles that produce a desired visible color and/or opacity and/or visual effect. The nanoparticle dispersion may include a colorant such as a pigment or dye having a particle size of less than 150nm, such as less than 70nm or less than 30 nm. Nanoparticles can be produced by milling raw organic or inorganic pigments with grinding media having a particle size of less than 0.5 mm. Examples of nanoparticle dispersions and their methods of manufacture are described in U.S. Pat. No.6,875,800B 2, incorporated herein by reference. Nanoparticle dispersions can also be produced by crystallization, precipitation, gas phase condensation, and chemical attrition (i.e., partial dissolution). To minimize re-aggregation of the nanoparticles in the coating, a dispersion of resin-coated nanoparticles may be used. As used herein, a "dispersion of resin-coated nanoparticles" refers to a continuous phase in which are dispersed discrete "composite particles" comprising nanoparticles and a resin coating on the nanoparticles. Examples of dispersions of resin-coated nanoparticles and methods of making the same are described in U.S. application 10/876,031 filed on 24.6.2004, which is incorporated by reference herein, and in U.S. provisional application 60/482,167 filed on 24.6.2003, which is also incorporated by reference herein.

Exemplary special effect compositions that can be used in the coatings of the present invention include pigments and/or compositions that produce one or more appearance effects such as reflectance, pearlescence, metallic sheen, phosphorescence, fluorescence, photochromism, photosensitivity, thermochromism, goniochromism (goniochromism), and/or color change. Additional special effect compositions may provide other perceptible properties such as opacity or texture. In one non-limiting embodiment, the special effect composition can produce a color shift such that the color of the coating changes when the coating is viewed at different angles. Exemplary color effect compositions are described in U.S. Pat. No.6,894,086, which is incorporated herein by reference. Additional color effect compositions can include transparent coated mica and/or synthetic mica, coated silica, coated alumina, transparent liquid crystal pigments, liquid crystal coatings, and/or any composition in which interference is caused by refractive index differences within the material and not due to refractive index differences between the surface of the material and the air.

The coatings of the present invention may be substantially transparent. As used herein, "substantially transparent" means that the coating can be seen through and that objects seen through the coating will be visible without significant distortion. It will be appreciated that the use of certain colorants will still result in a substantially clear coating.

In certain non-limiting embodiments, photosensitive compositions and/or photochromic compositions that reversibly change their color when exposed to one or more light sources can be used in the coatings of the present invention. Photochromic and/or photosensitive compositions can be activated by exposure to radiation of a particular wavelength. When the composition is excited, the molecular structure is altered 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 static state, wherein the original color of the composition is restored. In one non-limiting embodiment, the photochromic and/or photosensitive composition can be colorless in a non-excited state and exhibit color in an excited state. Complete discoloration can occur in milliseconds to several minutes, for example 20 seconds to 60 seconds. Exemplary photochromic and/or photosensitive compositions include photochromic dyes.

In one non-limiting embodiment, the photosensitive composition and/or photochromic composition can be associated with and/or at least partially associated with, for example by covalent bonding, with a polymer and/or polymeric material of the polymerizable component. In contrast to some coatings in which the photosensitive composition may migrate out of the coating and crystallize into the substrate, photosensitive compositions and/or photochromic compositions associated with and/or at least partially bound to polymers and/or polymerizable components according to non-limiting embodiments of the present invention have minimal migration out of the coating. Exemplary photosensitive and/or photochromic compositions and methods for their preparation are described in U.S. application No.10/892,919, filed on 7, 16, 2004, which is incorporated herein by reference.

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

The coating of the present invention can be applied to any substrate known in the art, such as automotive substrates and industrial substrates. These substrates are electrically conductive, such as metal, or treated to be electrically conductive, such as by application of a conductive paint.

The coating may be applied to a dry film thickness of 0.1 to 5 mils, e.g., 0.5 to 3.0 or 0.9 to 2.0 mils. Even thicker coatings, such as 20 to 100 mils, or up to 150 mils, are contemplated in certain embodiments of the invention. The coatings of the present invention may be used alone or in combination with other coatings. For example, the coating may be pigmented or unpigmented, and may be used in conjunction with a primer, basecoat, and/or topcoat.

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 if the term does not expressly appear. Additionally, any numerical range recited herein is intended to include all sub-ranges subsumed therein. Singular forms include plural forms and vice versa. For example, although reference is made herein, including the claims, to "a" rosin, "a" dienophile, "a" linker molecule, "an" epoxy resin, "a" rosin-containing compound, "a" modified epoxy, "an" epoxy resin, "a" compound having one or more reactive hydroxyl groups, and the like, one or more of each of these and any other components may be used. The term "polymer" as used herein refers to oligomers as well as homopolymers and copolymers, and the prefix "poly" refers to two or more.

Examples

The following examples are intended to illustrate the invention and should not be construed as limiting the invention in any way.

Example 1

		Mass (/ g)
			A	Gum rosin¹	496.25
B	Acrylic acid	102.72
			C	4-methoxyphenol	1.03

¹Brazilian gum rosin, available from Gehring-Montgomery.

Components A, B and C were fed into a flask equipped with an air inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 1 hour. The temperature was then raised to 170 ℃ and then held for 3 hours. The reaction mixture was then poured onto a foil-lined pan and allowed to cool before breaking into small pieces. The product had an acid value of 222.5 mgKOH/g.

Example 2

		Mass (/ g)
			A	SYLVAROS NCY²	165.1
B	Acrylic acid	34.55
			C	Hydroquinone	0.55

²Tall oil rosin from Arizona Chemical.

Components A, B and C were fed into a flask equipped with an air inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 1 hour. The temperature was then raised to 170 ℃ and then held for 3 hours. The reaction mixture was then poured onto a foil-lined pan and allowed to cool before breaking into small pieces. The product had an acid value of 225.1 mgKOH/g.

Example 3

		Mass (/ g)
			A	Gum rosin	518.67
B	Acrylic acid	80.52
			C	4-methoxyphenol	0.80

Components A, B and C were fed into a flask equipped with an air inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 1 hour. The temperature was then raised to 170 ℃ and then held for 3 hours. The reaction mixture was then poured onto a foil-lined pan and allowed to cool before breaking into small pieces. The product had an acid value of 213.2 mgKOH/g.

Example 4

		Mass (/ g)
			A	Gum rosin	496.25
B	Acrylic acid	102.72
			C	4-methoxyphenol	1.03

Components A, B and C were fed to a 1 liter agitated stainless steel pressure reactor. The stirring on the reactor was set to 500rpm and the reactor temperature was adjusted to 140 ℃. The temperature was then raised to 200 ℃ and the pressure was adjusted to 1000PSI with nitrogen. These conditions were maintained for 1 hour. The reactor was then cooled to 120 ℃ and vented, and the reaction mixture was poured onto a foil-lined pan and allowed to cool before breaking into small pieces. The product had an acid number of 231.7mg KOH/g.

Example 5

		Mass (/ g)
			1	EPON 828³	244.21
2	Rosin adduct of example 1	202.38
			3	Ethyl triphenyl phosphonium iodide	0.30
4	Methyl isobutyl ketone	26.01
			5	Methyl isobutyl ketone	0.73
6	Crosslinking agents, prepared as described below	194.84
			7	DETA Ketimine⁴	15.22
8	N-methylethanolamine	3.05

³Glycidyl ethers of bisphenol A, from Resolution.

⁴Ketimine formed from diethylenetriamine and methyl isobutyl ketone (72.69% solids in methyl isobutyl ketone).

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 1 hour. 5 was added and the temperature was adjusted to 127 ℃. Add 6 and 7, 1 minute later 8. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The modified epoxy resin mixture (618.1g) was dispersed in the aqueous medium by adding it to a mixture of 25.54g of sulfamic acid and 337.74g of deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, 5.32g of a 30% solution of gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 493.33g of deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with 27.8% solids. The reaction product had a Z-average molecular weight of 156783 (determined by gel permeation chromatography in DMF with polystyrene as a standard).

Example 6

		Mass (/ g)
			1	EPON 828	219.81
2	Rosin adduct of example 2	183.80
			3	Ethyl triphenyl phosphonium iodide	0.28
4	Methyl isobutyl ketone	23.51
			5	Methyl isobutyl ketone	0.66
6	Crosslinking agent	176.08
			7	DETA Ketimine	13.76
8	N-methylethanolamine	2.76

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 1 hour. 5 was added and the temperature was adjusted to 127 ℃. Add 6 and 7, 1 minute later 8. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The modified epoxy resin mixture (558.6g) was dispersed in an aqueous medium by adding it to a mixture of 23.08g sulfamic acid and 305.23g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, 4.80g of a 30% solution of gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 445.85g of deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with 31.0% solids. The reaction product had a Z-average molecular weight of 48876 (determined by gel permeation chromatography in DMF with polystyrene as a standard).

Example 7

		Mass (/ g)
			1	EPON 828	238.50
2	Rosin adduct of example 3	208.10
			3	Ethyl triphenyl phosphonium iodide	0.30
4	Methyl isobutyl ketone	26.01
			5	Methyl isobutyl ketone	0.73
6	Crosslinking agent	194.84
			7	DETA Ketimine	15.22
8	N-methylethanolamine	3.05

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 1 hour. 5 was added and the temperature was adjusted to 127 ℃. Add 6 and 7, 1 minute later 8. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The modified epoxy resin mixture (618.07g) was dispersed in the aqueous medium by adding it to a mixture of 25.54g sulfamic acid and 337.74g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, 5.32g of a 30% solution of gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 493.33g of deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with a solids content of 35.5%. The reaction product had a Z-average molecular weight of 33896 (determined by gel permeation chromatography in DMF using polystyrene as a standard).

Example 8

		Mass (/ g)
			1	EPON 828	245.76
2	Rosin adduct of example 4	200.84
			3	Ethyl triphenyl phosphonium iodide	0.30
4	Methyl isobutyl ketone	26.01
			5	Methyl isobutyl ketone	0.73
6	Crosslinking agent	194.84
			7	DETA Ketone DiImine(s)	15.22
8	N-methylethanolamine	3.05

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 1 hour. 5 was added and the temperature was adjusted to 127 ℃. Add 6 and 7, 1 minute later 8. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The modified epoxy resin mixture (618.07g) was dispersed in the aqueous medium by adding it to a mixture of 25.54g sulfamic acid and 337.74g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, 5.32g of a 30% solution of gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 493.33g of deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with 32.0% solids. The reaction product had a Z-average molecular weight of 47612 (determined by gel permeation chromatography in DMF with polystyrene as a standard).

The cross-linking agent is prepared from the following components:

composition (I)	Parts by weight
		Bis (hexamethylene) triamine⁵	1938.51
Propylene carbonate	1840.68
		Methyl isobutyl ketone	1619.65

⁵DYTEK BHMT-HP from Invista.

Bis (hexamethylene) triamine was fed to the reaction vessel and heated in a nitrogen atmosphere. The propylene carbonate was added over 3 hours. The reaction mixture exothermed to 68 ℃ and was then cooled and held at 60 ℃. The mixture was kept at 60 ℃ for another 2 hours and then methyl isobutyl ketone was added.

Example 9

This example describes the preparation of electrodeposition bath compositions. The electrodeposition bath was prepared from a mixture of the following components:

composition (I)	Parts by weight
		Resin and deionized water	See the following Table
Plasticizer⁶	7.3
		Toughening agent⁷	96.7
Flow additive⁸	74.8
		Ethylene glycol monohexyl ether	12.0
Propylene glycol monomethyl ether	5.7
		Pigment paste prepared as described below	140.8

⁶Mazo-1651, a plasticizer based on butyl carbitol and formaldehyde, from BASF.

⁷Aqueous dispersions of tougheners/flow control agents generally in accordance with U.S. Pat. No. 4,423,166. The toughening/flow control agent was prepared from polyepoxide (EPON 828) and polyoxyalkylene polyamine (JEFFAMINE D2000, from Texaco Chemical Co.). The toughening/flow control agent was dispersed in an aqueous medium with the aid of lactic acid and the dispersion had a resin solids content of 46.2 wt%.

⁸Cationic microgels were prepared as generally described in examples a and B of U.S. patent 5,096,556, except that acetic acid was used instead of lactic acid to disperse the soap of example a, and EPON 828 solution was added after stripping, rather than before, in example B. The resin had a final solids content of 17.9%.

Cationic dispersions	Weight parts of dispersion	Deionized water weight portion
			Example 7	987.5	1087.1
Example 8	1094.6	968.0

The coating is prepared by adding the plasticizer, toughening agent, flow additive and solvent to the cationic dispersion. The blend was then diluted with 500 parts deionized water. The pigment paste is diluted with 300 parts of deionized water and then mixed into the diluted resin mixture with stirring. The remainder of the deionized water was then added with stirring. The final bath solids was about 20% with a pigment to resin ratio of 0.12: 1.0. The coating was stirred for at least 2 hours. 30% of the total coating weight was removed by ultrafiltration and replaced with deionized water.

The pigment pastes used above were prepared from mixtures of the following components:

composition (I)	Parts by weight
		Cationic grinding resin⁹	525.3
SURFYNOL GA¹⁰	1.4
		Catalyst paste, prepared as described below	175.3
ASP-200¹¹	316.6
		CSX-333¹²	4.3
TRONOX CR800E¹³	40.3
		Deionized water	50.3

⁹As described in example 2 of US 4,715,898.

¹⁰Nonionic surfactants, available from Air Products and Chemicals, Inc.

¹¹Aluminum silicate, available from Engelhard Corporation.

¹²Pellets of carbon black, ex Cabot Corp.

¹³Titanium dioxide pigment from Tronox Inc.

The above ingredients were added sequentially with high shear stirring. After the ingredients were thoroughly mixed, the pigment paste was transferred to a vertical sand mill and ground to a Hegman value of about 7.25. The pigment paste is then collected. The solids content measured after 1 hour at 110 ℃ was 55%.

The catalyst paste was prepared from a mixture of the following ingredients:

composition (I)	Parts by weight
		Cationic grinding resin¹⁴	527.7
N-butoxy propanol	6.9
		FASCAT 4201¹⁵	312.0
Deionized water	59.8

¹⁴As described in example 2 of US 4,715,898, plus 2 wt% icoment-2 by solids, which is from BASF.

¹⁵From Arkema, inc.

The catalyst paste was prepared by sequentially adding the above ingredients under high shear stirring. After the ingredients were thoroughly mixed, the pigment paste was transferred to a vertical sand mill and ground to a Hegman value of about 7.25. The catalyst paste was then collected. The solids content measured after 1 hour at 110 ℃ was 51%.

Electrocoating procedure:

the bath composition prepared as described above was electrodeposited onto phosphated cold rolled steel panels available from ACT Laboratories. This phosphate salt, commercially available from PPG Industries, inc, is CHEMFOS 700 along with a deionized water rinse. Cationic electrodeposition conditions were 2 minutes at 92 ° F, with voltages listed in the table below, specifically for each resin, to produce a cured dry film thickness of about 0.80 mils. The electrocoated substrate was cured in an electric oven at 350 ° F for 25 minutes. The electrocoated panels were tested against standard electrocoat formulations and the results are reported in table 1. The control product was an ED-6280 electrophoretic paint from PPG Industries Inc.

TABLE 1

	Test coatings based on the dispersions of example 7	Test coatings based on the dispersions of example 8	ED6280 control coating
				Applying a voltage	150	200	175
Scribe creep-20 cycle corrosion test¹⁶	4.0mm	3.5mm	3.25mm
				Solvent resistance¹⁷	Very slight damage	Very slight damage	Has no influence on
Wet adhesion of QCT¹⁸	10	10	10

¹⁶Each coated panel was scribed through the coating to the metal substrate in an X pattern. The panels were then subjected to cyclic corrosion testing by rotating the test panels through a salt solution, drying at room temperature, and humidity and low temperature according to general automotive test method GM TM 54-26. Scribe creep is reported as the maximum width (in millimeters) of corrosion on the scribe mark.

¹⁷A piece of cloth soaked in acetone was rubbed back and forth over the plate for 100 double strokes (doublystrokes). The amount of surface damage that occurred was then rated.

¹⁸Cross-hatch adhesion tests were performed on a QCT condensation tester (Q-Panel Company, Cleveland, OH) before and after 16 hours of condensation humidity exposure (condensation humidity exposure) at 140F. A rating of 10 indicates no attachment failure.

Example 10

		Mass (/ g)
			1	Gum rosin	807.19
2	Toluene	200.48
			3	Paraformaldehyde (p-formaldehyde)	83.36
4	P-toluenesulfonic acid	8.97

Components 1-3 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 95 ℃ and held at this temperature for 90 minutes. The flask was then fitted with a Dean & Stark trap filled with toluene and warmed until reflux started. After 60 minutes toluene was removed from the Dean & Stark trap until the reflux temperature rose to 150 ℃. Reflux was continued for 3 hours and the water of reaction and toluene were removed as needed to maintain 150 ℃. The reaction mixture was then poured onto a foil-lined pan and allowed to cool before breaking into small pieces. The product had an acid number of 124.6mg KOH/g.

Example 11

		Mass (/ g)
			1	Gum rosin	204.64
2	Toluene	50.82
			3	Paraformaldehyde (p-formaldehyde)	42.26
4	P-toluenesulfonic acid	2.27

Components 1-3 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 95 ℃ and held at this temperature for 90 minutes. The flask was then fitted with a Dean & Stark trap filled with toluene and warmed until reflux started. After 60 minutes toluene was removed from the Dean & Stark trap until the reflux temperature rose to 150 ℃. Reflux was continued for 3 hours and the water of reaction and toluene were removed as needed to maintain 150 ℃. The reaction mixture was then poured onto a foil-lined pan and allowed to cool before breaking into small pieces. The product had an acid number of 122.2mg KOH/g.

Example 12

		Mass (/ g)
			1	Gum rosin	382.34
2	Toluene	94.96
			3	Paraformaldehyde (p-formaldehyde)	118.45
4	P-toluenesulfonic acid	4.25

Components 1-3 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 95 ℃ and held at this temperature for 90 minutes. The flask was then fitted with a Dean & Stark trap filled with toluene and warmed until reflux started. After 60 minutes toluene was removed from the Dean & Stark trap until the reflux temperature rose to 150 ℃. Reflux was continued for 3 hours and the water of reaction and toluene were removed as needed to maintain 150 ℃. The reaction mixture was then poured onto a foil-lined pan and allowed to cool before breaking into small pieces. The product had an acid number of 111.5mg KOH/g.

Example 13

		Mass (/ g)
			1	Rosin adduct of example 10	248.82
2	EPON 828	197.78
			3	Ethyl triphenyl phosphonium iodide	0.30
4	Methyl isobutyl ketone	20.30
			5	Methyl isobutyl ketone	6.44
6	Crosslinking agent prepared as described below	194.84
			7	DETA Ketimine	15.22
8	N-methylethanolamine	3.05

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 135 ℃ and then held at that temperature for 2 hours. 5 was added and the temperature was adjusted to 127 ℃. Add 6 and 7, 1 minute later 8. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The resin mixture (618.1g) was dispersed in the aqueous medium by adding it to a mixture of 25.54g sulfamic acid and 337.74g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, 5.32g of a 30% solution of gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 493.33g of deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with 30.4% solids. The reaction product had a Z-average molecular weight of 9852 (determined by gel permeation chromatography in DMF with polystyrene as a standard).

Example 14

		Mass (/ g)
			1	Rosin adduct of example 10	269.43
2	EPON 828³	196.57
			3	Ethyl triphenyl phosphonium iodide	0.32
4	Methyl isobutyl ketone	21.18
			5	Methyl isobutyl ketone	13.92
6	Crosslinking agent	172.81
			7	DETA Ketimine	13.50
8	N-methylethanolamine	2.70

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 135 ℃ and then held at that temperature for 2 hours. 5 was added and the temperature was adjusted to 127 ℃. Add 6 and 7, 1 minute later 8. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The resin mixture (621.4g) was dispersed in the aqueous medium by adding it to a mixture of 22.66g sulfamic acid and 337.27g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, a 30% solution of 5.34g gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 493.33g deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with 32.0% solids. The reaction product had a Z average molecular weight of 11238 (determined by gel permeation chromatography in DMF using polystyrene as a standard).

Example 15

		Mass (/ g)
			1	Rosin adduct of example 11	113.0
2	EPON 828	86.27
			3	Ethyl triphenyl phosphonium iodide	0.14
4	Methyl isobutyl ketone	9.06

5	Methyl isobutyl ketone	2.87
			6	Crosslinking agent	86.94
7	DETA Ketimine	6.79
			8	N-methylethanolamine	1.36

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 135 ℃ and then held at that temperature for 2 hours. 5 was added and the temperature was adjusted to 127 ℃. Add 6 and 7, 1 minute later 8. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The resin mixture (275.8g) was dispersed in the aqueous medium by adding it to a mixture of 11.4g sulfamic acid and 150.7g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, a 30% solution of 2.37g gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 220.12g deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with 23.0% solids. The reaction product had a Z-average molecular weight of 12204 (determined by gel permeation chromatography in DMF using polystyrene as a standard).

Example 16

		Mass (/ g)
			1	Rosin adduct of example 12	258.8
2	EPON 828	187.79
			3	Ethyl triphenyl phosphonium iodide	0.30
4	Methyl isobutyl ketone	20.30
			5	Methyl isobutyl ketone	6.44
6	Crosslinking agent	194.84
			7	DETA Ketimine	15.22
8	N-methylethanolamine	3.05

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 135 ℃ and then held at that temperature for 2 hours. 5 was added and the temperature was adjusted to 127 ℃. Add 6 and 7, 1 minute later 8. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The resin mixture (618.07g) was dispersed in the aqueous medium by adding it to a mixture of 25.54g sulfamic acid and 831.07g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, 5.32g of a 30% solution of gum rosin in butyl carbitol formaldehyde was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with a solids content of 33.0%. The reaction product had a Z-average molecular weight of 10474 (determined by gel permeation chromatography in DMF with polystyrene as a standard).

The crosslinker was prepared as described above in example 8.

Example 17

This example describes the preparation of an electrodeposition bath composition of the present invention. The electrodeposition bath was prepared from a mixture of the following components:

composition (I)	Parts by weight
		Cationic dispersion and deionized water	See the following Table
Plasticizer	8.3
		Toughening agent	121.9
Flow additive	80.6
		Ethylene glycol monohexyl ether	12.4
Propylene glycol monomethyl ether	6.2
		Pigment paste prepared as described above in example 9	140.8

Cationic dispersions	Weight parts of dispersion	Deionized water weight portion
			Example 13	1090.9	938.8

The coating is prepared by adding the plasticizer, toughening agent, flow additive and solvent to the cationic dispersion with agitation. The blend was then diluted with 500 parts deionized water. The pigment paste is diluted with 300 parts of deionized water and then blended into the diluted resin mixture with stirring. The remainder of the deionized water was then added with stirring. The final bath solids was about 20% with a pigment to resin ratio of 0.12: 1.0. The coating was stirred for at least 2 hours. 30% of the total coating weight was removed by ultrafiltration and replaced with deionized water.

Pigment paste and catalyst paste were prepared as described above in example 9.

Electrocoating procedure:

the bath composition prepared as described above was electrodeposited onto phosphated cold rolled steel panels available from ACT Laboratories. This phosphate salt is available from PPG Industries, inc. as Chemfos 700 along with a deionized water rinse. Cationic electrodeposition conditions were 2 minutes at 92 ° F, with voltages listed in the table below, specifically for each resin, to produce a cured dry film thickness of about 0.80 mils. The electrocoated substrate was cured in an electric oven at 325 ℃ F. for 25 minutes. The electrocoated panels were tested against standard electrocoat formulations and the results are reported in the table below. The control product was ED-6280 from PPG Industries Inc.

	Test coating based on the electrophoretic paint of example 17	ED6280 control coating
			Applying a voltage	210	175
Scribe creep-30 cycle corrosion test	5.5mm	5.0mm
			Solvent resistance	Very slight damage	Has no influence on
Wet adhesion of QCT	10	10

The above results demonstrate that the compositions of the invention, derived in part from low cost renewable resources, have similar performance to standard market-approved electrophoretic paints.

Example 18

		Mass (/ g)
			1	EPON 828	483.61
2	Gum rosin	528.92
			3	Ethyl triphenyl phosphonium iodide	0.69
4	Methyl isobutyl ketone	58.97
			5	MDI¹⁹	52.03
6	Methyl isobutyl ketone	63.03
			7	Crosslinking agent prepared as described below	389.77
8	DETA Ketimine	30.46
			9	N-methylethanolamine	6.10
10	Methyl isobutyl ketone	2.30

¹⁹LUPRANATE M20S from BASF Corp.

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 45 minutes. The temperature was adjusted to 132 ℃ and then 5 and 6 were added. The temperature was lowered to 127 ℃ and held for 30 minutes. Addition 7 and 8, 1 minute later 9 and 10. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The resin mixture (727.1g) was dispersed in the aqueous medium by adding it to a mixture of 21.29g sulfamic acid and 361.45g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, 6.09g of a 30% solution of gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 557.99g of deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with a solids content of 45.7%. The reaction product had a Z average molecular weight of 28358 (determined by gel permeation chromatography in DMF using polystyrene as a standard).

Example 19

		Mass (/ g)
			1	EPON 828	479.14
2	Gum rosin	524.02
			3	Ethyl triphenyl phosphonium iodide	0.68
4	Methyl isobutyl ketone	58.42
			5	MDI	64.43
6	Methyl isobutyl ketone	77.34
			7	Crosslinking agent	386.16
8	DETA Ketimine	30.18
			9	N-methylethanolamine	6.04
10	Methyl isobutyl ketone	2.28

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 45 minutes. The temperature was adjusted to 132 ℃ and then 5 and 6 were added. The temperature was lowered to 127 ℃ and held for 30 minutes. Addition 7 and 8, 1 minute later 9 and 10. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The resin mixture (732.9g) was dispersed in the aqueous medium by adding it to a mixture of 21.09g sulfamic acid and 355.82g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, 6.09g of a 30% solution of gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 557.96g of deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with 42.7% solids. The reaction product had a Z-average molecular weight of 43489 (determined by gel permeation chromatography in DMF using polystyrene as a standard).

Example 20

		Mass (/ g)
			1	EPON 828	473.88
2	Gum rosin	518.28
			3	Ethyl triphenyl phosphonium iodide	0.68
4	Methyl isobutyl ketone	57.78
			5	MDI	76.61
6	Methyl isobutyl ketone	91.77
			7	Crosslinking agent	381.93
8	DETA Ketimine	29.84
			9	N-methylethanolamine	8.36
10	Methyl isobutyl ketone	2.25

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 45 minutes. The temperature was adjusted to 132 ℃ and then 5 and 6 were added. The temperature was lowered to 127 ℃ and held for 30 minutes. Addition 7 and 8, 1 minute later 9 and 10. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The resin mixture (738.6g) was dispersed in an aqueous medium by adding it to a mixture of 20.86g sulfamic acid and 350.28g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, 6.09g of a 30% solution of gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 557.93g of deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with 40.2% solids. The reaction product had a Z-average molecular weight of 72971 (determined by gel permeation chromatography in DMF with polystyrene as a standard).

Example 21

		Mass (/ g)
			1	EPON 828	470.62
2	Gum rosin	557.14
			3	Ethyl triphenyl phosphonium iodide	0.70
4	Methyl isobutyl ketone	59.86
			5	MDI	76.72
6	Methyl isobutyl ketone	96.79
			7	Crosslinking agent	336.28
8	DETA Ketimine	39.42
			9	N-methylethanolamine	3.68
10	Methyl isobutyl ketone	2.34

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 45 minutes. The temperature was adjusted to 132 ℃ and then 5 and 6 were added. The temperature was lowered to 127 ℃ and held for 30 minutes. Addition 7 and 8, 1 minute later 9 and 10. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The resin mixture (739.6g) was dispersed in an aqueous medium by adding it to a mixture of 16.72g sulfamic acid and 347.59g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, 6.10g of a 30% solution of gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 555.00g of deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with 44.0% solids. The reaction product had a Z-average molecular weight of 55815 (determined by gel permeation chromatography in DMF with polystyrene as a standard).

Example 22

		Mass (/ g)
			1	EPON 828	313.18
2	Rosin S²⁰	342.52
			3	Ethyl triphenyl phosphonium iodide	0.45
4	Methyl isobutyl ketone	38.19
			5	MDI	42.75
6	Methyl isobutyl ketone	47.84
			7	Crosslinking agent	270.49
8	DETA Ketimine	19.72
			9	N-methylethanolamine	3.95
10	Methyl isobutyl ketone	1.49

²⁰Tall oil rosin from MeadWestvaco.

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 45 minutes. The temperature was adjusted to 132 ℃ and then 5 and 6 were added. The temperature was lowered to 127 ℃ and held for 30 minutes. Addition 7 and 8, 1 minute later 9 and 10. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The resin mixture (972.51g) was dispersed in an aqueous medium by adding it to a mixture of 27.58g sulfamic acid and 471.83g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, a 30% solution of 8.08g gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 740.00g deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with a solids content of 38.1%. The reaction product had a Z average molecular weight of 11710 (determined by gel permeation chromatography in DMF using polystyrene as a standard).

Example 23

		Mass (/ g)
			1	EPON 828	316.89
2	SYLVAROS NCY	338.80
			3	Ethyl triphenyl phosphonium iodide	0.45
4	Methyl isobutyl ketone	38.19
			5	MDI	42.75
6	Methyl isobutyl ketone	47.84
			7	Crosslinking agent	270.49
8	DETA Ketimine	19.72
			9	N-methylethanolamine	3.95
10	Methyl isobutyl ketone	1.49

Components 1-4 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 45 minutes. The temperature was adjusted to 132 ℃ and then 5 and 6 were added. The temperature was lowered to 127 ℃ and held for 30 minutes. Addition 7 and 8, 1 minute later 9 and 10. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The resin mixture (972.51g) was dispersed in an aqueous medium by adding it to a mixture of 27.58g sulfamic acid and 471.83g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, a 30% solution of 8.08g gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 740.00g deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with 41.3% solids. The reaction product had a Z average molecular weight of 16728 (determined by gel permeation chromatography in DMF with polystyrene as a standard).

Example 24

		Mass (/ g)
			1	EPON 828	310.56
2	Gum rosin	339.65
			3	Ethyl triphenyl phosphonium iodide	0.44
4	Methyl isobutyl ketone	38.30
			5	Trimethylolpropane	7.39
6	MDI	42.76
			7	Methyl isobutyl ketone	48.59
8	Crosslinking agent	268.23
			9	DETA Ketimine	19.56
10	N-methylethanolamine	3.92
			11	Methyl isobutyl ketone	1.48

Components 1-5 were fed to a flask equipped with a nitrogen inlet, stirrer, condenser and thermocouple. The flask contents were heated slowly until they reached 140 ℃ and then held at that temperature for 45 minutes. The temperature was adjusted to 132 ℃ and then 6 and 7 were added. The temperature was lowered to 127 ℃ and held for 30 minutes. Addition was 8 and 9, and after 1 minute 10 and 11 were added. After the exotherm, the temperature was adjusted to 116 ℃ and held at that temperature for 2 hours. The resin mixture (972.8g) was dispersed in the aqueous medium by adding it to a mixture of 27.34g sulfamic acid and 471.78g deionized water warmed to 30 ℃ with vigorous stirring. After 30 minutes, a 30% solution of 8.08g gum rosin in butyl carbitol formaldehyde was added, and after 45 minutes 740.00g deionized water was added. The dispersion was diluted with more deionized water and vacuum stripped to remove the organic solvent, resulting in a dispersion with 42.1% solids. The reaction product had a Z-average molecular weight of 44382 (determined by gel permeation chromatography in DMF using polystyrene as a standard).

While specific embodiments of the invention have been described above for purposes of illustration, it will be apparent to those skilled in the art that numerous variations of the details of the present invention may be made without departing from the invention as defined in the appended claims.

Claims

1. A cationic electrodepositable coating comprising rosin, wherein the rosin is reacted with an epoxy resin and the reaction product of the rosin and the epoxy resin having an epoxide equivalent weight of 180-

Wherein the rosin is reacted with a linker molecule, and further reacted with an epoxy resin, the linker molecule being formaldehyde.

2. The coating of claim 1, wherein the rosin is reacted with a carboxyl-containing dienophile, and further reacted with an epoxy resin.

3. The coating of claim 2, wherein the dienophile comprises acrylic acid.

4. The coating of claim 2, wherein the epoxy resin comprises a diglycidyl ether of bisphenol a.

5. The coating of claim 1, wherein the epoxy resin comprises a diglycidyl ether of bisphenol a.

6. The coating of claim 1, wherein the rosin comprises 10 to 90 weight percent of the coating based on total solids weight.

7. The coating of claim 1, wherein the rosin comprises 10 to 60 weight percent of the coating based on total solids weight.

8. The coating of claim 1, wherein the coating comprises a colorant.

9. The coating of claim 1, wherein the coating is substantially transparent.

10. The coating of claim 2, wherein at least some of the epoxy groups are reacted with a cationic salt forming compound.

11. The coating of claim 1, wherein at least some of the epoxy groups are reacted with a cationic salt forming compound.

12. The coating of claim 1, further comprising an aromatic-based or cyclic-based epoxy.

13. The coating of claim 12, wherein the aromatic-based epoxy is a bisphenol a-based epoxy.

14. The coating of claim 1, wherein the acrylic resin is not the primary film former.

15. The coating of claim 1, wherein the coating contains less than 5 weight percent acrylic resin.

16. The coating of claim 1, wherein the reaction product of the rosin and the epoxy resin is further reacted with a compound having one or more hydroxyl-reactive groups.

17. The coating of claim 16, wherein the compound having one or more hydroxyl-reactive groups comprises an isocyanate.