Electrodepositable coating composition comprising a layered silicate pigment and a dispersant

Abstract

The present invention relates to an electrodepositable coating composition comprising: a cationic electrodepositable binder; a layered silicate pigment; and a dispersant. Also disclosed are methods of making the electrodepositable coating composition, coatings derived from the electrodepositable coating composition and substrates coated with the coatings derived from the electrodepositable coating composition.

Description

Technical Field

[0001] The present invention relates to an electrodepositable coating composition, a coating derived from said electrodepositable coating composition, and a method for applying such a coating. Background Technology

[0002] As a coating application method, electrodeposition involves depositing a film-forming composition onto a conductive substrate under the influence of an applied electric potential. Electrodeposition has become the standard in the coating industry because, compared to non-electrophoretic coating methods, it offers increased paint utilization, less waste, improved substrate corrosion protection, and minimal environmental pollution.

[0003] Electrodepositable coatings typically contain pigments with multiple uses, and coloring electrodeposition baths are usually supplied as two components: (i) a resin blend and (ii) a pigment paste. The pigment paste comprises pigments and abrasive resin or abrasive carriers. The pigments and resins are typically milled together by a milling process to disperse the pigments into the abrasive resin to form the pigment paste. The use of abrasive carriers reduces pigment agglomeration and allows for uniform dispersion of the pigments throughout the coating bulk, but it involves additional manufacturing and formulation steps, resulting in higher costs. It also makes it difficult to incorporate high levels of pigment into the coating and weakens the corrosion-inhibiting properties of the coating by reducing the pigment-to-binder (P:B) ratio and crosslinking density.

[0004] The coating industry still needs cost-effective electrodepositable compositions that allow for higher pigment loading to provide improved corrosion resistance to metal substrates. Summary of the Invention

[0005] A cationic electrodepositable coating composition is disclosed, comprising: a cationic electrodepositable binder; and a layered silicate pigment-dispersant composite, wherein the composite has anionic charge.

[0006] The present invention also discloses a cationic electrodepositable coating composition comprising: a cationic electrodepositable binder containing a film-forming polymer with cationic salt groups; a layered silicate pigment; and a dispersant, wherein the cationic electrodepositable coating composition is formed by a method comprising the following steps: (1) heating an unneutralized film-forming polymer containing cationic salt groups to a high temperature; (2) adding the dispersant to the unneutralized film-forming polymer containing cationic salt groups under stirring to form a mixture, the unneutralized film-forming polymer containing cationic salt groups comprising a cationic film-forming polymer; (3) adding the layered silicate pigment to the mixture under stirring at a high temperature; and (4) dispersing the mixture of the film-forming polymer containing cationic salt groups, the layered silicate pigment, and the dispersant under stirring in an aqueous medium comprising water and a resin neutralizing acid, wherein the cationic salt groups in the film-forming polymer containing cationic salt groups are neutralized by the resin neutralizing acid to form a film-forming polymer containing cationic salt groups.

[0007] The present invention also discloses a method for preparing an electrodepositable coating composition, the method comprising the following steps:

[0008] (1) Heating an unneutralized cationic film-forming binder comprising a film-forming polymer containing cationic salt-forming groups to a high temperature; (2) Adding the dispersant to the unneutralized film-forming polymer containing cationic salt-forming groups under stirring to form a mixture; (3) Adding the layered silicate pigment to the mixture under stirring at a high temperature; and (4) Dispersing the mixture of the film-forming polymer containing cationic salt-forming groups, the layered silicate pigment, and the dispersant under stirring in an aqueous medium comprising water and a resin neutralizing acid, wherein the cationic salt-forming groups in the film-forming polymer containing cationic salt-forming groups are neutralized by the resin neutralizing acid to form a film-forming polymer containing cationic salt-forming groups.

[0009] The present invention further discloses a method for coating a substrate, the method comprising electrodepositing a coating of a cationic electrodepositable coating composition derived from the present invention onto at least a portion of the substrate.

[0010] The present invention also discloses a substrate, which is at least partially coated with a coating deposited by the cationic electrodepositable coating composition of the present invention. Detailed Implementation

[0011] The present invention relates to a cationic electrodepositable coating composition comprising, essentially consisting of, or composed of: a cationic electrodepositable coating composition including a cationic electrodepositable binder; a layered silicate pigment; and a dispersant.

[0012] As used herein, the term "electroplated coating composition" refers to a composition capable of being deposited onto a conductive substrate under the influence of an applied potential. The term "cationically electrodeposited coating composition" refers to an electrodeposited coating composition capable of being deposited onto a conductive substrate by a cationically electrodeposited process, wherein during the electrodeposition process, a coating deposited by the cationically electrodeposited coating composition is deposited on a conductive substrate serving as a cathode.

[0013] Cationic electrodeposition adhesives

[0014] According to the present invention, the cationic electrodepositable coating composition includes a cationic electrodepositable binder.

[0015] As used herein, the term "cationically electrodepositable adhesive" refers to an organic film-forming polymer containing cationic salt groups or cationic salt-forming groups (which can be at least partially neutralized to form cationic salt groups), which imparts a positive charge to the polymer and enables the polymer to be deposited onto a conductive substrate by a cationic electrodeposition process.

[0016] Cationic electrodeposition adhesives may include film-forming polymers containing cationic salt groups and optionally curing agents.

[0017] As described above, the cationic electrodepositable adhesive comprises a film-forming polymer containing cationic salt groups. Film-forming polymers containing cationic salt groups can be used in cationic electrodepositable coating compositions. As used herein, the term "film-forming polymer containing cationic salt groups" refers to a polymer containing at least partially neutralized cationic salt groups, such as positively charged sulfonium, ammonium, or phosphonium groups.

[0018] Film-forming polymers containing cationic salt groups include functional groups. The functional groups of film-forming polymers containing cationic salt groups may include active hydrogen functional groups. The term "active hydrogen" refers to hydrogen that, according to the Zerewitinoff test, exhibits activity due to the position of said hydrogen in the molecule, as described in the *Journal of the American Chemical Society*, Vol. 49, p. 3181 (1927). Therefore, active hydrogen contains hydrogen atoms bonded to oxygen, nitrogen, or sulfur, and thus useful compounds will contain those having at least two hydroxyl, thiol, primary amine, and / or secondary amine groups (in any combination). Film-forming polymers containing cationic salt groups that include active hydrogen functional groups can be referred to as active hydrogen-containing, cationic salt-containing film-forming polymers.

[0019] Examples of polymers suitable for use as film-forming polymers containing cationic salt groups in this invention include, but are not limited to, alkyd resin polymers, acrylic acid, polyepoxides, polyamides, polyureas, polyethers, and polyesters.

[0020] More specific examples of suitable film-forming polymers containing active hydrogen and cationic salt groups include polyepoxide-amine adducts, such as adducts of polyglycidyl ethers of polyphenols like bisphenol A with primary and / or secondary amines, as described in U.S. Patent No. 4,031,050, column 3, lines 27 through 5, line 50; U.S. Patent No. 4,452,963, column 5, lines 58 through 6, line 66; and U.S. Patent No. 6,017,432, column 2, lines 66 through 6, line 26, portions of which are incorporated herein by reference. A portion of the amine reacting with the polyepoxide may be a ketoimine of the polyamine, as described in U.S. Patent No. 4,104,147, column 6, lines 23 through 7, line 23, portions of which are incorporated herein by reference. Also suitable are ungelled polyepoxide-polyoxyethylene polyamine resins, such as those described in column 2, lines 60 through 5, lines 58 of U.S. Patent No. 4,432,850, the referenced portion of which is incorporated herein by reference. Alternatively, cationic acrylic resins may be used, such as those described in column 2, lines 18 through 3, lines 61 of U.S. Patent No. 3,455,806 and in column 2, lines 29 through 3, lines 21 of U.S. Patent No. 3,928,157, the portions of which are incorporated herein by reference.

[0021] In addition to resins containing amine salt groups, resins containing quaternary ammonium salt groups can also be used as film-forming polymers containing cationic salt groups in this invention. Examples of such resins are those formed by reacting organic polyepoxides with tertiary ammonium salts. Such resins are described in U.S. Patent No. 3,962,165, column 2, line 3 through column 11, line 7; U.S. Patent No. 3,975,346, column 1, line 62 through column 17, line 25; and U.S. Patent No. 4,001,156, column 1, line 37 through column 16, line 7, portions of which are incorporated herein by reference.

[0022] Other suitable examples of cationic resins include resins containing ternary sulfonate groups, such as those described in column 1, line 32 through column 5, line 20 of U.S. Patent No. 3,793,278, this portion of which is incorporated herein by reference. Furthermore, cationic resins cured via a transesterification mechanism may also be used, as described in European Patent Application No. 12463B1, page 2, line 1 through page 6, line 25, this portion of which is incorporated herein by reference.

[0023] Other suitable film-forming polymers containing cationic salt groups include those that can form photodegradable electrodepositable coating compositions. Such polymers include polymers comprising cationic amine salt groups derived from the side-amino and / or terminal amino groups disclosed in paragraphs

[0064] through

[0088] of U.S. Patent Application Publication 2003 / 0054193A1, this portion of which is incorporated herein by reference. Also suitable are hydrogen-containing, cationic salt-containing resins derived from polyglycidyl ethers of polyphenols, bonded to one or more aromatic groups, as described in paragraphs

[0096] through

[0123] of U.S. Patent Application Publication 2003 / 0054193A1, this portion of which is incorporated herein by reference. Also suitable are polypropylene oxide resins, such as DER-732, commercially available from Palmer Holland.

[0024] By at least partially neutralizing with a neutralizing acid, a film-forming polymer containing active hydrogen and cationic salt groups becomes cationic and water-dispersible. Suitable neutralizing acids include organic and inorganic acids. Non-limiting examples of suitable organic neutralizing acids include formic acid, acetic acid, methanesulfonic acid, and lactic acid. Non-limiting examples of suitable inorganic neutralizing acids include aminosulfonic acids. "Aminosulfonic acid" means aminosulfonic acid itself or its derivatives, such as those aminosulfonic acids or their derivatives having the following formula:

[0025]

[0026] Wherein R is hydrogen or an alkyl group having 1 to 4 carbon atoms. Mixtures of the acids mentioned above can also be used in this invention.

[0027] The degree of neutralization of film-forming polymers containing cationic salt groups can vary depending on the specific polymer involved. However, sufficient neutralizing acid should be used to adequately neutralize the film-forming polymers containing cationic salt groups so that they can be dispersed in an aqueous dispersion medium. For example, the amount of neutralizing acid used may provide at least 20% of the total theoretical neutralization. An excess of neutralizing acid, exceeding 100% of the total theoretical neutralization, may also be used. For example, the amount of neutralizing acid used to neutralize the film-forming polymer containing cationic salt groups may be ≥0.1% based on the total amines in the film-forming polymer containing active hydrogen and cationic salt groups. Alternatively, the amount of neutralizing acid used to neutralize the film-forming polymer containing active hydrogen and cationic salt groups may be ≤100% based on the total amines in the film-forming polymer containing active hydrogen and cationic salt groups. The total amount of neutralizing acid used to neutralize the film-forming polymer containing cationic salt groups can range between any combination of the values ​​stated in the preceding sentences (inclusive). For example, based on the total amines in the film-forming polymer containing cationic salt groups, the total amount of neutralizing acid used to neutralize the film-forming polymer containing active hydrogen and cationic salt groups can be 20%, 35%, 50%, 60%, or 80%. Other acidic additives can be incorporated into the electrodepositable composition, resulting in an increase in the total theoretical neutralization relative to the amount of neutralizing acid added alone. When these acidic additives are present in the composition, the total theoretical neutralization (%TN) can be 60% to 250% TN, such as 65% to 200% TN, such as 70% to 175% TN, such as 75% to 150% TN.

[0028] According to the present invention, based on the total weight of the resin solids in the cationic electrodepositable coating composition, the film-forming polymer containing cationic salt groups may be present in the cationic electrodepositable coating composition in an amount of at least 40% by weight, such as at least 50% by weight, such as at least 60% by weight, such as at least 64% by weight, such as at least 66% by weight, and may be present in an amount not exceeding 90% by weight, such as not exceeding 80% by weight, such as not exceeding 77% by weight, such as not exceeding 74% by weight, such as not exceeding 72% by weight. Based on the total weight of the resin solids in the cationic electrodepositable coating composition, the film-forming polymer containing cationic salt groups may be present in the cationic electrodepositable coating composition in an amount of 40% by weight to 90% by weight, such as 50% by weight to 80% by weight, such as 60% by weight to 77% by weight, such as 64% by weight to 74% by weight, such as 66% by weight to 72% by weight.

[0029] According to the present invention, the cationic electrodepositable adhesive of the cationic electrodepositable coating composition may optionally further include a curing agent. The curing agent reacts with functional groups on the film-forming polymer. For example, the curing agent may react with reactive groups (such as active hydrogen groups) of the film-forming polymer containing cationic salt groups to achieve curing of the coating composition to form a coating. As used herein, the terms “cured,” “cured,” or similar terms used in conjunction with the cationic electrodepositable coating composition described herein mean that at least a portion of the components forming the cationic electrodepositable coating composition crosslinks to form a coating. Furthermore, curing of the cationic electrodepositable coating composition refers to subjecting the composition to curing conditions (e.g., elevated temperatures) that cause the reactive functional groups of the components of the cationic electrodepositable coating composition to react, and cause the components of the composition to crosslink and form a coating that is at least partially cured. Non-limiting examples of suitable curing agents are at least partially blocked polyisocyanates, amino plastic resins, and phenolic plastic resins, such as phenol-formaldehyde condensates, containing their allyl ether derivatives.

[0030] Suitable at least partially blocked polyisocyanates include aliphatic polyisocyanates, aromatic polyisocyanates, and mixtures thereof. Curing agents may include at least partially blocked aliphatic polyisocyanates. For example, suitable at least partially blocked aliphatic polyisocyanates include: fully blocked aliphatic polyisocyanates, such as those described in column 1, lines 57 through 3, lines 15 of U.S. Patent No. 3,984,299, this portion of which is incorporated herein by reference; or partially blocked aliphatic polyisocyanates that react with the polymer backbone, such as those described in column 2, lines 65 through 4, lines 30 of U.S. Patent No. 3,947,338, this portion of which is also incorporated herein by reference. "Blocked" means that the isocyanate groups have reacted with the compound, resulting in blocked isocyanate groups that are stable to active hydrogen at ambient temperature (i.e., about 23°C and atmospheric pressure), but react with active hydrogen in the film-forming polymer at elevated temperatures (e.g., between 90°C and 200°C). Polyisocyanate curing agents can be fully blocked polyisocyanates with virtually no free isocyanate groups.

[0031] Polyisocyanate curing agents may include diisocyanates, higher-functional polyisocyanates, or combinations thereof. For example, polyisocyanate curing agents may include aliphatic polyisocyanates and / or aromatic polyisocyanates. Aliphatic polyisocyanates may comprise (i) alkylene isocyanates, such as trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate (“HDI”), 1,2-propylene diisocyanate, 1,2-butene diisocyanate, 2,3-butene diisocyanate, 1,3-butene diisocyanate, ethylene diisocyanate, and butylene diisocyanate, and (ii) cycloalkylene isocyanates, such as 1,3-cyclopentane diisocyanate, 1,4-cyclohexane diisocyanate, 1,2-cyclohexane diisocyanate, isophorone diisocyanate, methylene bis(4-cyclohexyl) isocyanate (“HMDI”), and cyclotrimers of 1,6-hexamethylene diisocyanate (also known as isocyanurate trimers of HDI, which can be obtained from Covestro). AG) commercially available) and m-tetramethylxylene diisocyanate (can be obtained) (Obtained commercially from Allnex SA). Aromatic polyisocyanates may comprise (i) arylene isocyanates, such as m-phenylene diisocyanate, p-phenylene diisocyanate, 1,5-naphthalene diisocyanate and 1,4-naphthalene diisocyanate, and (ii) arylene alkyl isocyanates, such as 4,4'-diphenylmethane (“MDI”), 2,4-methylphenylene diisocyanate or 2,6-methylphenylene diisocyanate (“TDI”) or mixtures thereof, 4,4-toluidine diisocyanate and xylene diisocyanate. Triisocyanates, such as triphenylmethane-4,4',4”-triisocyanate, 1,3,5-triisocyanatobenzene, and 2,4,6-triisocyanatotoluene, can also be used; tetraisocyanates, such as 4,4'-diphenyldimethylmethane-2,2',5,5'-tetraisocyanate; and polymeric polyisocyanates, such as methyl phenylene diisocyanate dimers and trimers. The curing agent may include blocked polyisocyanates selected from polymeric polyisocyanates (such as polymeric HDI, polymeric MDI, polymeric isophorone diisocyanate, etc.). The curing agent may also include blocked trimers of hexamethylene diisocyanate, which can be Desmodur Available commercially from Covestro. Mixtures of polyisocyanate curing agents can also be used.

[0032] The polyisocyanate curing agent may be at least partially blocked by at least one blocking agent selected from the following: 1,2-alkanediol, such as 1,2-propanediol; 1,3-alkanediol, such as 1,3-butanediol; benzyl alcohol, such as benzyl alcohol; allyl alcohol, such as allyl alcohol; caprolactam; dialkylamine, such as dibutylamine; and mixtures thereof. The polyisocyanate curing agent may be at least partially blocked by at least one 1,2-alkanediol having three or more carbon atoms (e.g., 1,2-butanediol).

[0033] Other suitable blocking agents include aliphatic, alicyclic, or aromatic alkyl monohydric alcohols or phenolic compounds, including, for example, low aliphatic alcohols such as methanol, ethanol, and n-butanol; alicyclic alcohols such as cyclohexanol; aromatic alkyl alcohols such as benzyl alcohol and methylphenylmethanol; and phenolic compounds such as phenol itself and substituted phenols such as cresol and nitrophenol, wherein the substituents do not affect the coating operation. Ethylene glycol ethers and ethylene glycol amines can also be used as blocking agents. Suitable glycol ethers include ethylene glycol butyl ether, diethylene glycol butyl ether, ethylene glycol methyl ether, and propylene glycol methyl ether. Other suitable blocking agents include oximes such as methyl ethyl ketone oxime, acetone oxime, and cyclohexanone oxime.

[0034] For example, blocking agents may include ethers or polyethers comprising hydroxyl groups and terminal groups having the structure -OR, wherein R is a C1 to C4 alkyl group, such as a C1 to C3 alkyl group or two terminal hydroxyl groups. Polyethers may include homopolymers, block copolymers, or random copolymers. For example, polyethers may include homopolymers of ethylene oxide or propylene oxide, or polyethers may include block or random copolymers comprising combinations of block or random ethylene oxide and propylene oxide. Such organic solvents may include the aforementioned structures. Such blocking groups may include the following structures:

[0035]

[0036] Wherein R1 and R2 are each hydrogen, or one of R1 and R2 is hydrogen and the other is methyl; R3 is H or C1 to C4 alkyl, such as C1 to C3 alkyl; and n is an integer from 1 to 50, such as 1 to 40, such as 1 to 30, such as 1 to 20, such as 1 to 12, such as 1 to 8, such as 1 to 6, such as 1 to 4, such as 2 to 50, such as 2 to 40, such as 2 to 30, such as 2 to 20, such as 2 to 12, such as 2 to 8, such as 2 to 6, such as 2 to 4, such as 2 to 50, such as 1 ...

[0037] The curing agent may optionally include high molecular weight volatile groups. As used herein, the term "high molecular weight volatile group" refers to a blocking agent and other organic byproduct that are generated and volatilized during the curing reaction of the electrodeposable coating composition, wherein the molecular weight of the high molecular weight volatile group is at least 70 g / mol, such as at least 125 g / mol, such as at least 160 g / mol, such as at least 195 g / mol, such as at least 400 g / mol, such as at least 700 g / mol, such as at least 1000 g / mol or higher, and may be in the range of 70 to 1,000 g / mol, such as 160 to 1,000 g / mol, such as 195 to 1,000 g / mol, such as 400 to 1,000 g / mol, such as 700 to 1,000 g / mol. For example, organic byproducts may include alcohol byproducts generated from the reaction of the film-forming polymer and the curing agent of amino or phenolic plastics, and the blocking agent may contain organic compounds, including alcohols, for blocking the isocyanate groups of the polyisocyanate that are not blocked during curing. For clarity, the high molecular weight volatile groups are covalently bonded to the curing agent prior to curing, and any organic solvents that may be present in the electrodepositable coating composition are explicitly excluded. During curing, the pigment-to-binder ratio of the deposited film may increase relative to the ratio of uncured pigment to binder deposited in the electrodepositable coating composition, due to the loss of higher quality blocking agents and other organic matter derived from the curing agent volatilizing during curing. Based on the total weight of the film-forming binder, the high molecular weight volatile groups may account for 5% to 50% by weight of the film-forming binder, such as 7% to 45% by weight, such as 9% to 40% by weight, such as 11% to 35% by weight, such as 13% to 30% by weight. Based on the total weight of the film-forming adhesive before and after curing, the high molecular weight volatile groups and other low molecular weight volatile organic compounds generated during curing, such as low molecular weight sealants and organic byproducts generated during curing, may be present in an amount such that the relative weight loss of the film-forming adhesive deposited on the substrate relative to the weight of the cured film-forming adhesive is 5% to 50% by weight, such as 7% to 45% by weight, such as 9% to 40% by weight, such as 11% to 35% by weight, such as 13% to 30% by weight of the film-forming adhesive dosage.

[0038] Curing agents may include amino plastic resins. Amino plastic resins are condensation products of aldehydes and substances carrying amino or amide groups. Condensation products obtained from the reaction of alcohols and aldehydes with melamine, urea, or benzomelamine can be used. However, condensation products of other amines and amides can also be used, such as aldehyde condensates of alkyl and aryl substituted derivatives of triazine, diazine, triazole, guanidine, guanidineamine, and alkyl and aryl substituted ureas and alkyl and aryl substituted melamines. Some examples of such compounds are N,N'-dimethylurea, benzourea, dicyandiamide, formaguanamine, acetoguanamine, ammeline, 2-chloro-4,6-diamino-1,3,5-triazine, 6-methyl-2,4-diamino-1,3,5-triazine, 3,5-diaminotriazole, triaminopyrimidine, 2-mercapto-4,6-diaminopyrimidine, and 3,4,6-tris(ethylamino)-1,3,5-triazine. Suitable aldehydes include formaldehyde, acetaldehyde, crotonaldehyde, acrolein, benzaldehyde, furfural, and glyoxal.

[0039] Amino plastic resins may contain methanol groups or similar alkyl alcohol groups, and at least a portion of these alkyl alcohol groups may be etherified by reaction with an alcohol to provide a resin soluble in organic solvents. For this purpose, any monohydric alcohol may be used, including alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, and other alcohols, as well as benzyl alcohol and other aromatic alcohols, cyclic alcohols such as cyclohexanol, monoethers of ethylene glycol such as cellolsolvers and carbitols, and halogenated or other substituted alcohols such as 3-chloropropanol and butoxyethanol.

[0040] A non-limiting example of commercially available amino plastic resins is the trademarked product of Allnex Belgium SA / NV. (such as CYMEL 1130 and 1156) and trademarked products from INEOS Melamines. Commercially available amino plastic resins (such as RESIMENE 750 and 753). Examples of suitable amino plastic resins are also included in the amino plastic resins described in column 16, line 3 through column 17, line 47 of U.S. Patent No. 3,937,679, this portion of which is hereby incorporated by reference. As disclosed in the foregoing portion of the '679 patent, amino plastics can be used in combination with methanol phenol ethers.

[0041] Phenolic resins are formed by the condensation of aldehydes and phenols. Suitable aldehydes include formaldehyde and acetaldehyde. Methylene releasers and aldehyde releasers (such as paraformaldehyde and hexamethylenetetramine) can also be used as aldehyde agents. Various phenols can be used, such as phenol itself, cresol, or substituted phenols, wherein a hydrocarbon group having a straight-chain, branched, or cyclic structure replaces hydrogen in an aromatic ring. Mixtures of these phenols can also be used. Some specific examples of suitable phenols are p-phenylphenol, p-tert-butylphenol, p-tert-pentylphenol, cyclopentylphenol, and unsaturated hydrocarbon-substituted phenols, such as monobutenylphenol containing a butenyl group at the ortho, meta, or para position, wherein the double bond appears at various positions in the hydrocarbon chain.

[0042] As described above, amino plastic resins and phenolic plastic resins are described in column 6, lines 20 through 7, lines 12 of U.S. Patent No. 4,812,215, the reference portion of which is incorporated herein by reference.

[0043] Based on the total weight of the resin solids in the electrodepositable coating composition, the curing agent may be present in the cationic electrodepositable coating composition in an amount of at least 10% by weight, such as at least 20% by weight, such as at least 25% by weight, and may be present in an amount not exceeding 60% by weight, such as not exceeding 50% by weight, such as not exceeding 40% by weight. Based on the total weight of the resin solids in the electrodepositable coating composition, the curing agent may be present in the cationic electrodepositable coating composition in an amount of 10% by weight to 60% by weight (such as 20% by weight to 50% by weight, such as 25% by weight to 40% by weight). As used herein, the weight attributable to the curing agent includes any blocking agents (including those that may volatilize during curing).

[0044] Layered silicate pigments and dispersants

[0045] According to the present invention, the cationic electrodepositable coating composition further comprises layered silicate pigments and dispersants.

[0046] As used herein, the term "layered silicate" refers to a group of minerals with silicate lamellae, whose basic structure is based on interconnected SiO4. -4 A tetrahedral six-membered ring, wherein the six-membered ring extends outward in infinite layers, wherein three of the four oxygen atoms in each tetrahedron are shared with the other tetrahedra, thus producing a basic structural unit of Si2O5. -2 Layered silicates. Layered silicates may include hydroxide ions and / or cations located at the center of the tetrahedron, such as Fe. +2 Mg +2 Or Al +3The ions form a cation layer between silicate layers, wherein the cations can coordinate with oxygen and / or hydroxide ions in the silicate layers. The term "layered silicate pigment" refers to a pigment material comprising layered silicates. Non-limiting examples of layered silicate pigments include mica, chlorite, serpentine, talc, and clay minerals. Clay minerals include, for example, kaolin clay and montmorillonite clay. The lamellar structure of layered silicate pigments tends to give the pigment a plate-like structure, but the pigment can be manipulated (e.g., by mechanical means) to have other particulate structures. These pigments may or may not swell upon exposure to a liquid medium and may or may not have leachable components (e.g., ions that may be attracted to the liquid medium).

[0047] As discussed above, layered silicate pigments can have a generally plate-like structure due to the lamellar stacked structure of layered silicates. The surfaces or faces of plate-like layered silicate pigments can have a negative charge, while the ends or edges of the plates can have a positive charge, and the layered silicate pigment as a whole typically has an overall negative charge. The total charge of a layered silicate pigment can depend on the pH of the medium in which it is dispersed. For example, kaolin clay can have an overall positive charge due to the protonation of metal oxides and hydroxides at pH values ​​below 2.2, and the magnitude of the negative charge increases at pH values ​​above 2.2 to 4.5 as acidic protons dissociate from the clay structure.

[0048] Layered silicate pigments may include plate-shaped pigments. For example, layered silicate pigments may include plate-shaped mica pigments, plate-shaped chlorite pigments, plate-shaped serpentine pigments, plate-shaped talc pigments, and / or plate-shaped clay pigments. The plate-shaped clay pigments may include kaolin clay, montmorillonite clay, or combinations thereof.

[0049] As used herein, the term "dispersant" refers to a material that can form a chemical complex with layered silicate pigments and can help promote the dispersion of layered silicate pigments.

[0050] Layered silicate pigments and dispersants can optionally form complexes, and the layered silicate pigment-dispersant complexes of the present invention can optionally have a total anionic charge. As used herein, the term "complex" refers to a substance formed by chemical interactions between two different chemical substances, such as ionic bonding, covalent bonding, and / or hydrogen bonding. As used herein, the term "total anionic charge" with respect to a complex means that the complex is at least partially negatively charged and may have some positively charged portions, but the negative charge is greater than the positive charge, such that the complex has an anionic charge. These substances will typically be part of a dispersed phase having one or more components insoluble in the bulk medium and other components soluble in the bulk material.

[0051] Dispersants may include dispersible acids. Dispersible acids may be monocarboxylic or polycarboxylic acids. As used herein, the term "polycarboxylic acid" refers to a chemical compound having more than one acid proton. As used herein, the term "acid proton" refers to a proton that forms part of an acid group, including but not limited to oxyacids of phosphorus, carboxylic acids, oxyacids of sulfur, etc.

[0052] Dispersive acids may include first acidic protons with a pKa of at least 1.1, such as at least 1.5, such as at least 1.8. Dispersive acids may include first acidic protons with a pKa of no more than 4.6, such as no more than 4.0, such as no more than 3.5. Dispersive acids may include first acidic protons with a pKa of 1.1 to 4.6, such as 1.5 to 4.0, such as 1.8 to 3.5.

[0053] Dispersed acids may include carboxylic acids, oxyacids of phosphorus (such as phosphoric acid or phosphonic acid), or combinations thereof.

[0054] Dispersing acids can form complexes with layered silicate pigments, and layered silicate pigment-dispersant complexes can include layered silicate pigment-dispersing acid complexes. The dispersing acid can be deprotonated in an aqueous medium of the composition to form a negative (or more negative) charge, and the deprotonated acid dispersant can form a complex with the positively charged edges of the plate-like layered silicate pigment. Optionally, the complex can have a more negative overall charge than the layered silicate pigment itself; that is, the layered silicate pigment-dispersant complex can have an overall anionic charge.

[0055] The weight-to-molar ratio of the layered silicate pigment to the dispersant can be at least 0.25 g / mmol, such as at least 0.5 g / mmol, such as at least 1.0 g / mmol, such as at least 1.5 g / mmol, such as at least 1.75 g / mmol. The weight-to-molar ratio of the layered silicate pigment to the dispersant can not exceed 25 g / mmol, such as not exceeding 15 g / mmol, such as not exceeding 10 g / mmol, such as not exceeding 8.25 g / mmol, such as not exceeding 6.5 g / mmol, such as not exceeding 5.0 g / mmol. The weight ratio of layered silicate pigment to molar dispersant can be as follows: 0.25 to 25 g / mmol, 0.25 to 15 g / mmol, 0.25 to 10 g / mmol, 0.25 to 8.25 g / mmol, 0.25 to 6.5 g / mmol, 0.25 to 5.0 g / mmol, 0.5 to 25 g / mmol, 0.5 to 15 g / mmol, 0.5 to 10 g / mmol, 0.5 to 8.25 g / mmol, 0.5 to 6.5 g / mmol, 0.5 to 5.0 g / mmol, 1 to 25 g / mmol, 1 to 15 g / mmol, etc. 1 to 10 g / mmol, such as 1 to 8.25 g / mmol, such as 1 to 6.5 g / mmol, such as 1 to 5.0 g / mmol, such as 1.5 to 25 g / mmol, such as 1.5 to 15 g / mmol, such as 1.5 to 10 g / mmol, such as 1.5 to 8.25 g / mmol, such as 1.5 to 6.5 g / mmol, such as 1.5 to 5.0 g / mmol, such as 1.75 to 25 g / mmol, such as 1.75 to 15 g / mmol, such as 1.75 to 10 g / mmol, such as 1.75 to 8.25 g / mmol, such as 1.75 to 6.5 g / mmol, such as 1.75 to 5.0 g / mmol.

[0056] The pigment to binder (P:B) ratio described in this invention can refer to the weight ratio of pigment to binder in the electrophoretic coating bath composition, and / or the weight ratio of pigment to binder in the deposited wet film, and / or the weight ratio of pigment to binder in the dried uncured deposited film, and / or the weight ratio of pigment to binder in the cured film. The pigment to binder (P:B) ratio of layered silicate pigment to cationic electrodepositable binder can be at least 0.20:1, such as at least 0.25:1, such as at least 0.30:1, such as at least 0.35:1, such as at least 0.40:1, such as at least 0.50:1, such as at least 0.60:1, such as at least 0.75:1, such as at least 1:1, such as at least 1.25:1, such as at least 1.5:1. The pigment to binder (P:B) ratio of layered silicate pigments to cationic electrodepositable binders may not exceed 2.0:1, such as not exceeding 1.75:1, not exceeding 1.5:1, not exceeding 1.25:1, not exceeding 1:1, not exceeding 0.75:1, not exceeding 0.70:1, not exceeding 0.60:1, not exceeding 0.55:1, or not exceeding 0.50:1. The pigment to binder (P:B) ratio of layered silicate pigments to cationic electrodepositable binders can be from 0.2:1 to 2.0:1, such as 0.2:1 to 1.75:1, such as 0.2:1 to 1.50:1, such as 0.2:1 to 1.25:1, such as 0.2:1 to 1:1, such as 0.2:1 to 0.75:1, such as 0.2:1 to 0.70:1, such as 0.2:1 to 0.60:1, such as 0.2:1 to 0.5... 5:1, such as 0.2:1 to 0.50:1, such as 0.25:1 to 2.0:1, such as 0.25:1 to 1.75:1, such as 0.25:1 to 1.50:1, such as 0.25:1 to 1.25:1, such as 0.25:1 to 1:1, such as 0.25:1 to 0.75:1, such as 0.25:1 to 0.70:1, such as 0.25:1 to 0.60:1, such as 0.25:1 to 0.55:1, such as 0.25 :1 to 0.50:1, e.g., 0.3:1 to 2.0:1, e.g., 0.3:1 to 1.75:1, e.g., 0.3:1 to 1.50:1, e.g., 0.3:1 to 1.25:1, e.g., 0.3:1 to 1:1, e.g., 0.3:1 to 0.75:1, e.g., 0.3:1 to 0.70:1, e.g., 0.3:1 to 0.60:1, e.g., 0.3:1 to 0.55:1, e.g., 0.3:1 to 0.50:1, e.g., 0.35:1 to 2.0:1, such as 0.35:1 to 1.75:1, such as 0.35:1 to 1.50:1, such as 0.35:1 to 1.25:1, such as 0.35:1 to 1:1, such as 0.35:1 to 0.75:1, such as 0.35:1 to 0.70:1, such as 0.35:1 to 0.60:1, such as 0.35:1 to 0.55:1, such as 0.35:1 to 0.50:1, such as 0.4:1 to 2.0:1, such as 0.4:1 to 1.75:1, such as 0.4:1 to 1.50:1, such as 0.4:1 to 1.25:1, such as 0.4:1 to 1:1, such as 0.4:1 to 0.75:1, such as 0.4:1 to 0.70:1, such as 0.4:1 to 0.60:1, such as 0.4:1 to 0.55:1, such as 0.4:1 to 0.50:1, such as 0.5:1 to 2.0: 1, e.g., 0.5:1 to 1.75:1, 0.5:1 to 1.50:1, 0.5:1 to 1.25:1, 0.5:1 to 1:1, 0.5:1 to 0.75:1, 0.5:1 to 0.70:1, 0.5:1 to 0.60:1, 0.5:1 to 0.55:1, 0.6:1 to 2.0:1, 0.6:1 to 1 0.75:1, such as 0.6:1 to 1.50:1, such as 0.6:1 to 1.25:1, such as 0.6:1 to 1:1, such as 0.6:1 to 0.75:1, such as 0.6:1 to 0.70:1, such as 0.75:1 to 2.0:1, such as 0.75:1 to 1.75:1, such as 0.75:1 to 1.50:1, such as 0.75:1 to 1.25:1, Examples of ratios include: 0.75:1 to 1:1; 1:1 to 2.0:1; 1:1 to 1.75:1; 1:1 to 1.50:1; 1:1 to 1.25:1; 1.25:1 to 2.0:1; 1.25:1 to 1.75:1; 1.25:1 to 1.50:1; 1.50:1 to 2.0:1; and 1.50:1 to 1.75:1.

[0057] Based on the total solid weight of the composition, the dispersant may be present in an amount of at least 0.1% by weight, such as at least 0.3% by weight, such as at least 0.5% by weight, such as at least 0.7% by weight, such as at least 0.8% by weight, such as 1% by weight. Based on the total solid weight of the composition, the dispersant may be present in an amount of not more than 10% by weight, such as not more than 7.5% by weight, such as not more than 5% by weight, such as not more than 3% by weight, such as not more than 2% by weight, such as not more than 1.5% by weight, such as not more than 1% by weight, such as not more than 0.8% by weight. Based on the total solid weight of the composition, the dispersant may be present in an amount of 0.1% by weight to 10% by weight, such as 0.1% by weight to 7.5% by weight, such as 0.1% by weight to 5% by weight, such as 0.1% by weight to 3% by weight, such as 0.1% by weight to 2% by weight, such as 0.1% by weight to 1.5% by weight, such as 0.1% by weight to 1% by weight, such as 0.1% by weight to 0.8% by weight, such as 0.3% by weight to 10% by weight, such as 0.3% by weight to 7.5% by weight, such as 0.3% by weight. Up to 5% by weight, e.g., 0.3% by weight to 3% by weight, e.g., 0.3% by weight to 2% by weight, e.g., 0.3% by weight to 1.5% by weight, e.g., 0.3% by weight to 1% by weight, e.g., 0.3% by weight to 0.8% by weight, e.g., 0.5% by weight to 10% by weight, e.g., 0.5% by weight to 7.5% by weight, e.g., 0.5% by weight to 5% by weight, e.g., 0.5% by weight to 3% by weight, e.g., 0.5% by weight to 2% by weight, e.g., 0.5% by weight to 1.5% by weight, e.g., 0.5% by weight % to 1% by weight, e.g., 0.5% to 0.8% by weight, e.g., 0.7% to 10% by weight, e.g., 0.7% to 7.5% by weight, e.g., 0.7% to 5% by weight, e.g., 0.7% to 3% by weight, e.g., 0.7% to 2% by weight, e.g., 0.7% to 1.5% by weight, e.g., 0.7% to 1% by weight, e.g., 0.7% to 0.8% by weight, e.g., 0.8% to 10% by weight, e.g., 0.8% to 7.5% by weight, e.g., 0% to 1% by weight. The amount present is 0.8% to 5% by weight, such as 0.8% to 3% by weight, such as 0.8% to 2% by weight, such as 0.8% to 1.5% by weight, such as 0.8% to 1% by weight, such as 1% to 10% by weight, such as 1% to 7.5% by weight, such as 1% to 5% by weight, such as 1% to 3% by weight, such as 1% to 2% by weight, such as 1% to 1.5% by weight, such as 1% to 1% by weight, such as 1% to 0.8% by weight.

[0058] The present invention also relates to a cationic electrodepositable coating composition comprising: a cationic electrodepositable binder containing a film-forming polymer with cationic salt groups; a layered silicate pigment; and a dispersant, wherein the cationic electrodepositable coating composition is formed by a method comprising the following steps: (1) heating an unneutralized film-forming polymer containing cationic salt groups to a high temperature; (2) adding the dispersant to the unneutralized film-forming polymer containing cationic salt groups under stirring to form a mixture, the unneutralized film-forming polymer containing cationic salt groups comprising a cationic film-forming polymer; (3) adding the layered silicate pigment to the mixture under stirring at a high temperature; and (4) dispersing the mixture of the film-forming polymer containing cationic salt groups, the layered silicate pigment, and the dispersant under stirring in an aqueous medium comprising water and a resin neutralizing acid, wherein the cationic salt groups in the film-forming polymer containing cationic salt groups are neutralized by the resin neutralizing acid to form the film-forming polymer containing cationic salt groups. The cationic binder may optionally further include a curing agent, which may be added during or after any of steps 1 to 4. The layered silicate pigment and dispersant may optionally form a layered silicate pigment-dispersant composite, and / or the layered silicate pigment, dispersant, and film-forming polymer containing cationic salt groups may optionally form a layered silicate pigment-dispersant-film-forming polymer composite containing cationic salt groups.

[0059] Other components of the cationic electrodepositable coating composition

[0060] In addition to the cationic electrodepositable binders, layered silicate pigments and dispersants described above, the cationic electrodepositable coating compositions according to the present invention may optionally include one or more additional components.

[0061] According to the present invention, the cationic electrodepositable coating composition comprises an aqueous medium containing water and optionally one or more organic solvents. Based on the total weight of the electrodepositable coating composition, the aqueous medium may be present, for example, in an amount from 40% to 90% by weight, such as from 50% to 75% by weight. Examples of suitable organic solvents include oxygen-containing organic solvents such as monoalkyl ethers of ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol containing 1 to 10 carbon atoms in the alkyl group, such as monoethyl ethers and monobutyl ethers of these glycols. Examples of other at least partially water-miscible solvents include alcohols such as ethanol, isopropanol, butanol, and diacetone alcohol. If used, the organic solvent may generally be present in an amount of less than 10% by weight, such as less than 5% by weight, based on the total weight of the electrodepositable coating composition. The electrodepositable coating composition may be specifically provided in the form of a dispersion, such as an aqueous dispersion.

[0062] For example, organic solvents may include ethers or polyethers comprising hydroxyl groups and terminal groups having the structure -OR, wherein R is a C1 to C4 alkyl group, such as a C1 to C3 alkyl group or two terminal hydroxyl groups. Polyethers may include homopolymers, block copolymers, or random copolymers. For example, polyethers may include homopolymers of ethylene oxide or propylene oxide, or polyethers may include block or random copolymers comprising combinations of block or random ethylene oxide and propylene oxide. Such organic solvents may include the following structures:

[0063]

[0064] Wherein R1 and R2 are each hydrogen, or one of R1 and R2 is hydrogen and the other is methyl; R3 is H or C1 to C4 alkyl, such as C1 to C3 alkyl; and n is an integer from 1 to 50, such as 1 to 40, such as 1 to 30, such as 1 to 20, such as 1 to 12, such as 1 to 8, such as 1 to 6, such as 1 to 4, such as 2 to 50, such as 2 to 40, such as 2 to 30, such as 2 to 20, such as 2 to 12, such as 2 to 8, such as 2 to 6, such as 2 to 4, such as 2 to 50, such as 1 ...

[0065] According to the present invention, based on the total weight of the electrodeposable coating composition, the total solids content of the cationic electrodeposable coating composition can be at least 1% by weight, such as at least 5% by weight, and can not exceed 50% by weight, such as not exceeding 40% by weight, or not exceeding 20% ​​by weight. Based on the total weight of the electrodeposable coating composition, the total solids content of the cationic electrodeposable coating composition can be from 1% by weight to 50% by weight, such as from 5% by weight to 40% by weight, or from 5% by weight to 20% by weight. As used herein, “total solids” refers to the non-volatile contents of the cationic electrodeposable coating composition, i.e., materials that will not volatilize when heated to 110°C for 15 minutes.

[0066] The pH of the cationic electrodepositable coating composition can be 3.0 to 6.5, 3.0 to 6.0, such as 3.0 to 5.5, such as 3.0 to 5.0, such as 3.0 to 4.5, such as 3.0 to 4.0, such as 3.0 to 3.5, such as 3.5 to 6.5, such as 3.5 to 6.0, such as 3.5 to 5.5, such as 3.5 to 5.0, such as 3.5 to 4.5, such as 3.5 to 4.0, such as 4.0 to 6.5, such as 4.0 to 6.0, such as 4.0 to 5.5, such as 4.0 to 5.0, such as 4.0 to 4.5.

[0067] According to the present invention, the electrodepositable coating composition may optionally include a catalyst for catalyzing a reaction between, for example, a curing agent and a binder component of a film-forming polymer. Examples of catalysts suitable for cationic electrodepositable coating compositions include, but are not limited to, organotin compounds (e.g., dibutyltin oxide and dioctyltin oxide) and their salts (e.g., dibutyltin diacetate); other metal oxides (e.g., oxides of cerium, zirconium, and bismuth) and their salts (e.g., bismuth sulfamate and bismuth lactate); or cyclic guanidines as described in column 1, lines 53 through 4, lines 18 and 16, lines 62 through 19, lines 8 of U.S. Patent No. 7,842,762, the referenced portion of which is incorporated herein by reference. During curing, the catalyst may be activated by external energy such as thermal energy from heating.

[0068] According to the present invention, the cationic electrodepositable coating composition may include other optional components, such as non-layered silicate pigments and various additives (if desired), such as fillers, plasticizers, antioxidants, biocides, UV light absorbers and stabilizers, hindered amine light stabilizers, defoamers, fungicides, dispersants, flow control agents, surfactants, wetting agents, or combinations thereof. Alternatively, the cationic electrodepositable coating composition may be completely free of any optional components, i.e., the optional components are not present in the cationic electrodepositable coating composition. Non-layered silicate pigments may include, for example, iron oxide, lead oxide, strontium chromate, carbon black, coal powder, titanium dioxide, barium sulfate, and colored pigments such as cadmium yellow, cadmium red, and chrome yellow. Based on the total weight of the resin solids in the electrodepositable coating composition, the other additives mentioned above may be present in the cationic electrodepositable coating composition in an amount from 0.01% by weight to 3% by weight.

[0069] According to the present invention, the cationic electrodepositable coating composition may be substantially free of, essentially free of, or completely free of tin. As used herein, a cationic electrodepositable coating composition is substantially free of tin if tin is present in an amount of less than 0.1% by weight based on the total weight of the resin blend solids. As used herein, a cationic electrodepositable coating composition may be essentially free of tin if tin is present in an amount of less than 0.01% by weight based on the total weight of the resin blend solids. As used herein, a cationic electrodepositable coating composition is completely free of tin if tin is not present in the composition based on the total resin blend solids, i.e., 0.00% by weight.

[0070] According to the present invention, the cationic electrodepositable coating composition may be substantially free of, essentially free of, or completely free of bismuth. As used herein, a cationic electrodepositable coating composition is substantially free of bismuth if bismuth is present in an amount of less than 0.1% by weight based on the total weight of the resin blend solids. As used herein, a cationic electrodepositable coating composition may be essentially free of bismuth if bismuth is present in an amount of less than 0.01% by weight based on the total weight of the resin blend solids. As used herein, a cationic electrodepositable coating composition is completely free of bismuth if bismuth is not present in the composition based on the total resin blend solids, i.e., 0.00% by weight.

[0071] According to the present invention, the cationic electrodepositable coating composition may be substantially free of, essentially free of, or completely free of metallic pigments. As used herein, the term "metallic pigment" refers to metallic and metal alloy pigments that consist primarily of metals in their elemental (zero valence) state. Metal particles may comprise zinc, aluminum, cadmium, magnesium, beryllium, copper, silver, gold, iron, titanium, nickel, manganese, chromium, scandium, yttrium, zirconium, platinum, tin, and their alloys, as well as various grades of steel. As used herein, the cationic electrodepositable coating composition is substantially free of metallic pigments if the metallic pigment is present in an amount of less than 5% by weight based on the total weight of the pigments in the composition. As used herein, the cationic electrodepositable coating composition is essentially free of metallic pigments if the metallic pigment is present in an amount of less than 1% by weight based on the total weight of the pigments in the composition. As used herein, the cationic electrodepositable coating composition is completely free of metallic pigments if the metallic pigment is not present in the composition based on the total weight of the pigments in the composition, i.e., 0.00% by weight.

[0072] According to the present invention, the cationic electrodepositable coating composition may be substantially free of, essentially free of, or completely free of silane dispersants. As used herein, a cationic electrodepositable coating composition is substantially free of silane dispersants if, based on the total solid weight of the composition, the silane dispersant (if present) is present in an amount of less than 1% by weight. As used herein, a cationic electrodepositable coating composition is essentially free of silane dispersants if, based on the total solid weight of the composition, the silane dispersant (if present) is present in an amount of less than 0.1% by weight. As used herein, a cationic electrodepositable coating composition is completely free of silane dispersants if, based on the total solid weight of the composition, the silane dispersant is not present in the composition, i.e., 0.00% by weight.

[0073] Method for preparing cationic electrodepositable coating compositions

[0074] The present invention also relates to a method for preparing an electrodepositable coating composition. The method comprises the following steps: (1) heating an unneutralized cationic film-forming binder comprising a film-forming polymer containing cationic salt-forming groups to a high temperature; (2) adding the dispersant to the unneutralized film-forming polymer containing cationic salt-forming groups under stirring to form a mixture; (3) adding the layered silicate pigment to the mixture under stirring at a high temperature; and (4) dispersing the mixture of the film-forming polymer containing cationic salt-forming groups, the layered silicate pigment, and the dispersant under stirring in an aqueous medium comprising water and a resin-neutralizing acid, wherein the cationic salt-forming groups in the film-forming polymer containing cationic salt-forming groups are neutralized by the resin-neutralizing acid to form a film-forming polymer containing cationic salt-forming groups. The cationic binder may optionally further comprise a curing agent, and the curing agent may be added during or after any of steps 1 to 4. The layered silicate pigment and the dispersant may form a layered silicate pigment-dispersant composite. Layered silicate pigments, dispersants, and film-forming polymers containing cationic salt groups can also form layered silicate pigment-dispersant-film-forming polymer complexes containing cationic salt groups.

[0075] The method of the present invention eliminates the need for preparing separate pigment compositions (e.g., pigment pastes or grinding carriers) by allowing pigment incorporation, without requiring conventional grinding and / or conventional grinding of resins into commercially viable electrophoretic coating feeds. Currently, electrodeposable coating compositions are commercially available as two-component (2K) or one-component (1K) products. In the case of a 2K system, separate resin blends and separate pigment pastes are sold to the customer. The customer then combines these materials with water in a specified ratio to form a stable electrophoretic coating bath. Electrophoretic coating suppliers also supply some customers with one-component systems. However, these 1K systems are still produced from two separate components, but these components are combined by the electrophoretic coating supplier into a single electrophoretic coating feed before being shipped to the customer. Thus, these 1K systems are effectively still manufactured from two components. In contrast, the cationic electrodeposable coating compositions of the present invention can be truly one-component electrodeposable coating compositions, which are produced without the use of separately milled pigment pastes. As used herein, "single-component electrodepositable coating composition" refers to a colored electrodepositable coating composition manufactured as a single component of a dispersing binder and pigment, without a separate pigment-containing composition.

[0076] According to the present invention, the electrodepositable coating composition may optionally be substantially free of, essentially free of, or completely free of abrasive resin. As used herein, the term "abrasive resin" refers to a resin that is chemically different from the main film-forming polymer used during the milling of pigments to form a pigment paste. As used herein, the electrodepositable coating composition is substantially free of abrasive resin if the abrasive resin (if present) is present in an amount not exceeding 5% by weight based on the total resin solids of the composition. As used herein, the electrodepositable coating composition is essentially free of abrasive resin if the abrasive resin (if present) is present in an amount not exceeding 3% by weight based on the total resin solids of the composition. As used herein, the electrodepositable coating composition is completely free of abrasive resin if the abrasive resin is not present in the composition based on the total resin solids of the composition, i.e., 0.00% by weight.

[0077] Not intended to be bound by any theory, it is believed that the interaction between layered silicate pigments, dispersants, and resins, such as through layered silicate pigment-dispersant complexes or layered silicate pigment-dispersant-film-forming polymer complexes containing cationic salt groups, allows the dispersion of layered silicate pigments into resins without milling. Agglomeration typically occurs through the interaction of negatively charged pigment faces with positively charged pigment edges, resulting in a “house of cards” type stacking of pigment particles (i.e., a network of edge-to-face stacked plate-like pigment particles). It is believed that the interaction between dispersants and / or film-forming polymers containing cationic salt groups and layered silicate pigments, such as through composites, occurs at the edges of the pigment, resulting in fewer positively charged edges (and the overall particle) and / or more negatively charged. The neutralization of positively charged edges leads to less or no ionic attraction and may even result in ionic repulsion of pigment particles, thereby reducing the tendency for pigment agglomeration.

[0078] According to the present invention, the method for preparing an electrodeposable coating composition may further include a grinding and / or milling step, followed by dispersing the mixture of the film-forming polymer containing cationic salt-forming groups, the layered silicate pigment, and the dispersant under stirring in an aqueous medium comprising water and a resin-neutralizing acid, wherein the cationic salt-forming groups in the film-forming polymer containing cationic salt-forming groups are neutralized by the resin-neutralizing acid to form the film-forming polymer containing cationic salt-forming groups. The optional grinding and / or milling step can produce a more stable electrophoretic coating bath.

[0079] With or without grinding, layered silicate pigments can also be incorporated into the electrodeposable coating compositions of the present invention using standard methods employed in industry, such as the preparation of pigment pastes or grinding carriers.

[0080] substrate

[0081] The cationic electrodepositable coating compositions of the present invention can be applied to a variety of substrates. Therefore, the present invention further relates to a substrate at least partially coated with a coating deposited by the cationic electrodepositable coating compositions described herein. It should be understood that the cationic electrodepositable coating compositions can be applied to the substrate as a single coating or as a coating in a multilayer coating composite. The cationic electrodepositable coating compositions can be electrophoretically deposited on any conductive substrate. Suitable substrates include metallic substrates, metallic alloy substrates, and / or metallized substrates, such as nickel-plated plastics. Alternatively, the substrate may include non-metallic conductive materials, including composites comprising, for example, materials comprising carbon fibers or conductive carbon. According to the present invention, the metal or metallic alloy may include cold-rolled steel, hot-rolled steel, zinc-coated steel, zinc compounds, or zinc alloys, such as electro-galvanized steel, hot-dip galvanized steel, galvanized hot-dip galvanized steel, and zinc-plated steel. Aluminum alloys of the 2XXX, 5XXX, 6XXX, or 7XXX series, as well as clad aluminum alloys and cast aluminum alloys of the A356 series, may also be used as substrates. Magnesium alloys from the AZ31B, AZ91C, AM60B, or EV31A series can also be used as the substrate. The substrate used in this invention may also include titanium and / or titanium alloys. Other suitable non-ferrous metals include copper and magnesium, as well as alloys of these materials. Suitable metallic substrates for use in this invention include those commonly used in: vehicle body assemblies (e.g., but not limited to doors, body panels, trunk lids, top panels, hoods, top and / or longitudinal beams, rivets, landing gear assemblies, and / or skins used on aircraft), vehicle frames, vehicle components, motorcycles, wheels, industrial structures and components such as household appliances including washing machines, dryers, refrigerators, stoves, dishwashers, etc., agricultural equipment, lawn and garden equipment, air conditioning units, heat pump units, lawn furniture, and other articles of manufacture. As used herein, “vehicle” or variations thereof include, but are not limited to, civil, commercial, and military aircraft and / or land vehicles, such as automobiles, motorcycles, and / or trucks. The metallic substrate may also be in the form of, for example, sheet metal or manufactured parts. It should also be understood that the substrate can be pretreated with a pretreatment solution comprising a zinc phosphate pretreatment solution, such as those described in U.S. Patent Nos. 4,793,867 and 5,588,989, or a zirconium-containing pretreatment solution, such as those described in U.S. Patent Nos. 7,749,368 and 8,673,091.

[0082] Coating methods, coatings, and coated substrates

[0083] The present invention also relates to a method for coating a substrate (such as any of the conductive substrates described above). According to the invention, such a method may include electrodepositing a coating derived from a cationic electrodepositable coating composition as described above onto at least a portion of the substrate. The method may optionally further include subjecting the coating to curing conditions (e.g., heating) to form a coating that is at least partially cured on the substrate. According to the invention, the method may include (a) electrodepositing a coating from a cationic electrodepositable coating composition of the present invention onto at least a portion of the substrate, and may optionally include (b) heating the coated substrate to a temperature and time sufficient to at least partially cure the electrodeposited coating on the substrate. According to the invention, the method may optionally further include (c) directly applying one or more pigment-containing coating compositions and / or one or more pigment-free coating compositions to the at least partially cured electrodeposited coating to form a primer and / or topcoat over at least a portion of the at least partially cured electrodeposited coating, and (d) heating the coated substrate from step (c) to a temperature and time sufficient to cure the primer and / or topcoat. The primer and / or topcoat may also be applied to the electrodeposited coating prior to the heating step (b), and the individual layers in the coating may be cured simultaneously by heating the coating for a time sufficient to cure the coating according to the heating step (d).

[0084] According to the present invention, the composition can be deposited on a conductive substrate by contacting the cationic electrodepositable coating composition of the invention with a conductive cathode and a conductive anode, wherein the surface to be coated is the cathode. Upon contact with the composition, an adhesive film of the coating composition is deposited on the cathode when a sufficient voltage is applied between the electrodes. The conditions for electrodeposition are generally similar to those used in the electrodeposition of other types of coatings. The applied voltage can vary and can be, for example, from as low as one volt to as high as several kilovolts, such as between 50 volts and 500 volts. The current density can be between 0.5 amperes per square foot and 15 amperes per square foot, and tends to decrease during electrodeposition, indicating the formation of an insulating film.

[0085] Once the cationic electrodepositable coating composition is electrodeposited onto at least a portion of a conductive substrate, the coated substrate is heated to a temperature and held for a time sufficient to at least partially cure the electrodeposited coating on the substrate. As used herein, the term "at least partially cured" with respect to a coating means the formation of a coating by subjecting the coating composition to curing conditions that cause at least a portion of the reactive groups of the components of the coating composition to chemically react to form the coating. The coated substrate can be heated to temperatures ranging from 250℉ to 450℉ (121.1°C to 232.2°C), such as 275℉ to 400℉ (135°C to 204.4°C) or 300℉ to 360℉ (149°C to 180°C). The curing time can depend on the curing temperature and other variables, such as the film thickness of the electrodeposited coating, the level and type of catalyst present in the composition, etc. For the purposes of this invention, all that is necessary is sufficient time to allow the coating on the substrate to cure. For example, the curing time can range from 10 minutes to 60 minutes, such as 20 to 40 minutes. The thickness of the resulting cured electrodeposited coating can range from 15 to 50 micrometers.

[0086] If desired, the electrodeposable coating composition of the present invention can also be applied to a substrate using non-electrophoretic coating techniques such as flow coating, dip coating, spray coating, and roll coating. For non-electrophoretic coating, the coating composition can be applied to conductive substrates as well as non-conductive substrates such as glass, wood, and plastics.

[0087] The present invention further relates to a coating formed by depositing a coating from a cationic electrodepositable coating composition described herein onto a substrate. The coating may be in a cured state or at least partially cured. Thus, a substrate may be coated with a coating comprising at least partially cured cationic electrodepositable binder and layered silicate pigment, and a dispersant. The layered silicate pigment may optionally be present as a layered silicate pigment-dispersant composite and / or a layered silicate pigment-dispersant-film-forming polymer composite containing cationic salt groups. Either composite may optionally have a total anionic charge.

[0088] The present invention further relates to a substrate at least partially coated with a coating deposited by the cationic electrodepositable coating composition described herein. The coating on the substrate may be in a cured state or at least partially cured. The coating comprises at least partially cured cationic electrodepositable binder and layered silicate pigments, as well as a dispersant. The layered silicate pigments may optionally be present as layered silicate pigment-dispersant composites and / or layered silicate pigment-dispersant-film-forming polymer composites containing cationic salt groups. Either composite may optionally have a total anionic charge.

[0089] Multi-layer coated composite materials

[0090] As described herein, the cationic electrodepositable coating compositions of the present invention can be used for electrophoretic coatings, which are part of a multilayer coating composite comprising a substrate having various coatings. The coating may comprise a pretreatment layer, such as a phosphate layer (e.g., a zinc phosphate layer or an iron phosphate layer) or a zirconium oxide layer, an electrophoretic coating produced by the cationic electrodepositable coating compositions of the present invention, optionally a primer layer, and a suitable topcoat layer (e.g., a base coating, a clear coating, a colored single coating, and a colored plus clear coating composite composition). It should be understood that a suitable topcoat layer comprises any of those coatings known in the art, and each may independently be water-based, solvent-based, in the form of solid particles (i.e., a powder coating composition), or in the form of a powder paste. Topcoats typically comprise a film-forming polymer, a crosslinking material, and one or more pigments (if it is a colored base coating or a single coating). According to the invention, a primer layer is disposed between the electrophoretic coating and the base coating. According to the invention, one or more topcoat layers may be applied to a substantially uncured substrate. For example, a clear coating may be applied to at least a portion of a substantially uncured base coating (wet-on-wet), and both layers may be cured simultaneously in a downstream process.

[0091] Furthermore, the topcoat layer can be applied directly onto the electrodepositable coating. In other words, the substrate may lack a primer layer. For example, the base coating can be applied directly onto at least a portion of the electrodepositable coating.

[0092] It will also be understood that a topcoat layer can be applied over the substrate, even if the substrate is not fully cured. For example, a clear coat can be applied over the base coat even if the base coat has not undergone a curing step. The two layers can then be cured during a subsequent curing step, thereby eliminating the need to separately cure the base coat and the clear coat.

[0093] According to the present invention, additional components may be present in various coating compositions that produce the topcoat layer, such as colorants and fillers. Any suitable colorant and filler can be used. For example, the colorant can be added to the coating in any suitable form (e.g., discrete particles, dispersions, solutions, and / or flakes). A single colorant or a mixture of two or more colorants can be used in the coatings of the present invention. It should be noted that, generally, the colorant can be present in any amount sufficient to impart the desired properties, visual and / or color effects in one layer of a multilayer composite material.

[0094] Example colorants include pigments, dyes, and colorants, such as those used in the paint industry and / or listed in the Dry Color Manufacturers Association (DCMA), as well as special effects compositions. Colorants may comprise, for example, finely divided solid powders that are insoluble but wettable under operating conditions. Colorants may be organic or inorganic, and may be agglomerated or non-agglomerated. Colorants can be incorporated into the coating by grinding or simple mixing. Colorants can be incorporated into the coating by grinding with an abrasive medium (such as an acrylic abrasive medium), the use of which is well known to those skilled in the art.

[0095] Example pigments and / or pigment compositions include, but are not limited to, carbazole dioxazine crude pigments, azo, monoazo, diazo, naphthol AS, salts (salt lakes), benzimidazolone, condensates, metal complexes, isoindolineone, isoindoline and polycyclic phthalocyanine, quinacridone, perylene, perinone, diketopyrrolopyrrole, thioindigo, anthraquinone, indigoanthraquinone, anthraquinone pyrimidine, flavinthrone, pinanthraquinone, anthraquinone, dioxazine, triaryl cations, quinophthalone pigments, pyrrolopyrrole dione red (“DPP Red BO”), titanium dioxide, carbon black, zinc oxide, antimony oxide, etc., as well as organic or inorganic UV opaque pigments (such as iron oxide), transparent red or yellow iron oxide, phthalocyanine blue and mixtures thereof. The terms “pigment” and “colored filler” may be used interchangeably.

[0096] Example dyes include, but are not limited to, solvent-based and / or water-based dyes, such as acid dyes, azo dyes, basic dyes, direct dyes, disperse dyes, reactive dyes, solvent dyes, sulfur dyes, mordant dyes, for example, bismuth vanadate, anthraquinone, perylene, aluminum, quinacridone, thiazole, thiazide, azo, indigo derivatives, nitro, nitroso, oxazine, phthalocyanine, quinoline, symmetrical diphenylethylene, and triphenylmethane.

[0097] Example colorants include, but are not limited to, pigments dispersed in a water-based or water-miscible carrier, such as AQUA-CHEM 896 available from Degussa, CHARISMA COLORANTS and MAXITONERINDUSTRIAL COLORANTS available from Eastman Chemical Company’s Precision Dispersions division.

[0098] Colorants can be in dispersion form, including, but not limited to, nanoparticle dispersions. Nanoparticle dispersions can contain one or more highly dispersed nanoparticle colorants and / or colorant particles that produce a desired visible color and / or opacity and / or visual effect. Nanoparticle dispersions can contain colorants such as pigments or dyes with particle sizes less than 150 nm, such as less than 70 nm or less than 30 nm. Nanoparticles can be produced from organic or inorganic pigments in milling feedstocks having abrasive media with a particle size less than 0.5 mm. Example nanoparticle dispersions and methods of their manufacture are identified in U.S. Patent No. 6,875,800B2, which is incorporated herein by reference. Nanoparticle dispersions can also be produced by crystallization, precipitation, vapor-phase condensation, and chemical abrasion (i.e., partial dissolution). To minimize reagglomeration of nanoparticles within a coating, resin-coated nanoparticle dispersions can be used. As used herein, a "resin-coated nanoparticle dispersion" refers to a continuous phase comprising finely dispersed "composite microparticles" including nanoparticles and a resin coating on the nanoparticles. Example resin-coated nanoparticle dispersions and methods for their manufacture are determined in U.S. Application No. 10 / 876,031, filed June 24, 2004 (which is incorporated herein by reference) and U.S. Provisional Application No. 60 / 482,167, filed June 24, 2003 (which is incorporated herein by reference).

[0099] According to the present invention, special effect compositions that can be used in one or more layers of a multilayer coated composite material comprise pigments and / or compositions that produce one or more appearance effects, such as reflection, pearlescent, metallic luster, phosphorescence, fluorescence, photochromism, photosensitivity, thermochromism, iridescence, and / or color change. Additional special effect compositions may provide other perceptible properties, such as reflectivity, opacity, or texture. For example, a special effect composition may produce color transfer, such that the color of the coating changes when viewed from different angles. Example color effect compositions are identified in U.S. Patent No. 6,894,086, which is incorporated herein by reference. Additional color effect compositions may comprise transparently coated mica and / or synthetic mica, coated silica, coated alumina, transparent liquid crystal pigments, liquid crystal coatings, and / or any composition, wherein interference arises from a difference in refractive index within the material rather than from a difference in refractive index between the material surface and air.

[0100] According to the present invention, photosensitive compositions and / or photochromic compositions, which reversibly change color when exposed to one or more light sources, can be used in many layers of a multilayer composite material. The photochromic and / or photosensitive compositions can be activated by exposure to radiation of a specific wavelength. When the composition is excited, its molecular structure changes, and the altered structure exhibits a new color different from the original color of the composition. When the radiation exposure is removed, the photochromic and / or photosensitive composition can revert to a resting state, where the original color of the composition is restored. For example, the photochromic and / or photosensitive composition may be colorless in the unexcited state and exhibit color in the excited state. The complete color change can occur within milliseconds to several minutes (e.g., 20 to 60 seconds). Example photochromic and / or photosensitive compositions contain photochromic dyes.

[0101] According to the present invention, photosensitive compositions and / or photochromic compositions can be associated with and / or at least partially bonded to polymeric materials of polymers and / or polymerizable components, such as by covalent bonding. Unlike some coatings in which photosensitive compositions can migrate out of the coating and crystallize into the substrate, the migration outside the coating of photosensitive compositions and / or photochromic compositions associated with and / or at least partially bonded to polymers and / or polymerizable components according to the present invention is minimal. Example photosensitive compositions and / or photochromic compositions and methods of their manufacture are identified in U.S. Application Serial No. 10 / 892,919, filed July 16, 2004, and are incorporated herein by reference.

[0102] As used herein, unless otherwise defined, the term “substantially free” means, based on the total resin solids weight of the composition, that the component, if present, is present in an amount of less than 1% by weight.

[0103] As used herein, unless otherwise defined, the term “substantially free” means, based on the total resin solids weight of the composition, that the component, if present, is present in an amount of less than 0.1% by weight.

[0104] As used herein, unless otherwise defined, the term “completely free” means, based on the total resin solids weight of the composition, that the component is not present in the electrodeposable coating composition, i.e., 0.00 wt%.

[0105] For the purposes of detailed description, it should be understood that the invention may take various alternative variations and sequences of steps unless explicitly stated otherwise. Furthermore, all numbers, such as those representing values, quantities, percentages, ranges, subranges, or fractions, can be interpreted as if they begin with the word "about," even if the term is not explicitly stated. Therefore, unless indicated otherwise, the numerical parameters set forth in the following description and the appended claims are approximations that may vary depending on the desired properties to be obtained by the invention. At least, and without attempt to limit the application of the doctrine of equivalence to the scope of the claims, each numerical parameter should be interpreted at least according to the number of significant figures reported and by applying ordinary rounding techniques. In the case of closed or open numerical ranges described herein, all numbers, values, quantities, percentages, subranges, and fractions within or covered by said numerical ranges should be considered as specifically included in and belonging to the original disclosure of this application, as if such numbers, values, quantities, percentages, subranges, and fractions had been fully and explicitly stated.

[0106] Although the numerical ranges and parameters illustrating the broad scope of the invention are approximate, the values ​​described in the specific examples are reported as accurately as possible. However, any numerical value inherently contains some error that is necessarily caused by the standard deviation found in its corresponding test measurement results.

[0107] As used herein, unless otherwise stated, plural terms may cover their singular counterparts and vice versa, unless otherwise stated. For example, although this document refers to “a” layered silicate pigment, “a” dispersant, “a” film-forming polymer containing cationic salt groups, and “a” curing agent, combinations of these components (i.e., multiple) may be used. Additionally, in this application, unless otherwise specifically stated, the use of “or” means “and / or”, even if “and / or” may be explicitly used in certain circumstances.

[0108] As used herein, the terms “comprising,” “containing,” and similar terms are understood in the context of this application to be synonymous with “comprising” and are therefore open-ended and do not exclude the presence of additional undescribed or unstated elements, materials, components, or method steps. As used herein, “consisting of” is understood in the context of this application to exclude the presence of any unstated elements, components, or method steps. As used herein, “essentially consisting of” is understood in the context of this application to include the specified elements, materials, components, or method steps “as well as elements, materials, components, or method steps that do not materially affect the essential and novel characteristics of the described content.”

[0109] As used herein, the terms “on,” “to,” “applied on,” “applied to,” “formed on,” “deposited on,” and “deposited onto” mean to form, cover, deposit, or provide on a surface but not necessarily in contact with said surface. For example, an electrodepositable coating composition “deposited on a substrate” does not exclude the presence of one or more other intermediate coatings of the same or different compositions positioned between the electrodepositable coating composition and the substrate.

[0110] As used herein, the term "polymer" broadly refers to both prepolymers, oligomers, and homopolymers and copolymers. It should be noted that the prefix "polymer" indicates two or more.

[0111] As used in this article, "adduct" refers to the product of the direct addition of two or more different molecules, producing a single reaction product containing all atoms of all the components.

[0112] As used herein, the term "resin solids" or "resin blend solids" includes cationic electrodepositable binders and any additional water-dispersible, non-coloring components.

[0113] While specific embodiments of the invention have been described in detail, those skilled in the art will understand that various modifications and alternatives to those details can be developed based on the general teachings of this disclosure. Therefore, the specific arrangements disclosed are intended to be illustrative only and not to limit the scope of the invention, which is defined by the full scope of the appended claims and any and all their equivalents.

[0114] The following examples illustrate the invention; however, these examples should not be construed as limiting the invention to its details. Unless otherwise indicated, all parts and percentages in the following examples and throughout the specification are by weight.

[0115] Example

[0116] Resin preparation

[0117] Prepare the following resin systems (or electrodepositable adhesives) for use in the examples described more fully below, as indicated.

[0118] Resin System I: Resin system used for comparative examples

[0119] Preparation of Crosslinking Agent I: A blocked polyisocyanate crosslinking agent suitable for electrodepositable coating resins was prepared as follows. Components 2-5 listed in Table 2 below were mixed in a flask set to total reflux under nitrogen atmosphere. The mixture was heated to 35°C, and component 1 was added dropwise, causing the temperature to rise due to the exothermic reaction and remain below 100°C. After the addition of component 1 was complete, a temperature of 110°C was established in the reaction mixture, and the reaction mixture was maintained at this temperature until no residual isocyanate was detected by IR spectroscopy. Component 6 was then added, and the reaction mixture was stirred at 100°C for 30 minutes, then removed from the flask and allowed to cool to ambient temperature.

[0120] Table 2. Components used to prepare crosslinking agent I

[0121] serial number Components Parts by weight (grams) 1 <![CDATA[Polymethylene diphenyl diisocyanate 1 > 1340.00 2 Dibutyltin dilaurate 2.61 3 Methyl isobutyl ketone 200.00 4 Diethylene glycol monobutyl ether 324.46 5 Ethylene glycol monobutyl ether 945.44 6 Methyl isobutyl ketone 122.85

[0122] 1 Rubinate M is available from Huntsman Corporation.

[0123] Preparation of cationic amine-functionalized polyepoxide-based resin (resin system I). The cationic amine-functionalized polyepoxide-based polymeric resin suitable for formulating electrodepositable coating compositions was prepared as follows: Components 3-5 listed in Table 1 below were combined in a flask set to total reflux under nitrogen stirring. The mixture was heated to 130°C and allowed to exotherm (up to 175°C). A temperature of 145°C was established in the reaction mixture, which was then maintained for 2 hours. Components 6-8 were then introduced into the reaction mixture, and a temperature of 110°C was established. Components 9 and 10 were then rapidly added to the reaction mixture, and the reaction mixture was allowed to exotherm. A temperature of 121°C was established in the reaction mixture, which was maintained for 1 hour. After maintenance, the heat source was removed from the reaction mixture, and component 11 was slowly introduced. The contents of the flask were poured into a container and allowed to cool. The resulting resin synthesis product I had a solid content of 65% by weight.

[0124] Table 3. Components used to prepare resin system I

[0125]

[0126] 1 EPON 828 is available from Hexion Corporation.

[0127] 2 See the synthesis of crosslinking agent I above.

[0128] 3The reaction product of 1 equivalent of diethylenetriamine and 72.7 wt% (in MIBK) of 2 equivalents of MIBK diketimine.

[0129] Resin System II: Resin systems for Examples 2 to 23

[0130] Crosslinker II was prepared as follows: a blocked polyisocyanate crosslinker suitable for electrodepositable coating resins was prepared. Components 2 and 3, listed in Table 4 below, were added to a flask set to total reflux under stirring under nitrogen. The contents of the flask were heated to 35°C, and component 1 was added dropwise, causing the temperature to rise due to the exothermic reaction and remain below 100°C. After the addition of component 1 was complete, a temperature of 100°C was established in the reaction mixture, and the reaction mixture was maintained at this temperature until no residual isocyanate was detected by IR spectroscopy. Components 4 and 5 were then added, and the reaction mixture was stirred at 100°C for 30 minutes. The mixture was then removed from the flask and allowed to cool to ambient temperature.

[0131] Table 4. Components used in the preparation of crosslinking agent II

[0132] serial number Components Parts by weight (grams) 1 <![CDATA[Polymethylene diphenyl diisocyanate 1 > 1422.05 2 <![CDATA[K Kat XK 620 (zinc amidine) 2 > 3.49 3 Diethylene glycol monobutyl ether 1721.64 4 Butylcarbidol formaldehyde 12.73 5 Bisphenol A–ethylene oxide adduct (1 / 6 molar ratio BPA / EtO) 140.08

[0133] 1 Rubinate M is available from Huntsman Corporation.

[0134] 2 Available from King Industries

[0135] Preparation of cationic amine-functionalized polyepoxide-based resins (Resin System II). The cationic amine-functionalized polyepoxide-based polymeric resins suitable for formulating electrodepositable coating compositions were prepared as follows: Components 5-4 listed in Table 1 below were combined in a flask set to total reflux under nitrogen stirring. The mixture was heated to 130°C and allowed to exotherm (up to 175°C). A temperature of 145°C was established in the reaction mixture, which was then maintained for 1 hour. Component 5 was then introduced into the flask, followed by components 6-7, and a temperature of 100°C was established in the reaction mixture. Premixed components 8 and 9 were then rapidly added to the reaction mixture, and the reaction mixture was allowed to exotherm. A temperature of 110°C was established, and the reaction mixture was maintained for 1 hour. After maintenance, the contents of the flask were discarded and cooled to room temperature.

[0136] Table 5. Components used in the preparation of resin system II

[0137]

[0138] 1EPON 828 is available from Hansen Corporation.

[0139] 2 See the synthesis of crosslinking agent II above.

[0140] 3 Available from Huntsman or Air Products.

[0141] Resin System III: Resin System for Example 24

[0142] Crosslinker III was prepared as follows: a blocked polyisocyanate crosslinker suitable for electrodepositable coating resins was prepared. Components 2 and 3, listed in Table 6 below, were added to a flask set to total reflux under nitrogen atmosphere. The contents of the flask were heated to 35°C, and component 1 was added dropwise, causing the temperature to rise exothermically and remain below 100°C. After the addition of component 1 was complete, a temperature of 100°C was established in the reaction mixture, and the reaction mixture was maintained at this temperature until no residual isocyanate was detected by IR spectroscopy. Components 4 and 5 were then added, and the reaction mixture was stirred at 100°C for 30 minutes. The mixture was then removed from the flask and allowed to cool to ambient temperature.

[0143] Table 6. Components used in the preparation of crosslinking agent III

[0144]

[0145]

[0146] 1 Rubinate M is available from Huntsman Corporation.

[0147] 2 Available from Aldrich.

[0148] Preparation of cationic amine-functionalized polyepoxide-based resins (Resin System III). The cationic amine-functionalized polyepoxide-based polymeric resins suitable for formulating electrodepositable coating compositions were prepared as follows: Components 7-4 listed in Table 1 below were combined in a flask set to total reflux under nitrogen stirring. The mixture was heated to 130°C and allowed to exotherm (up to 175°C). A temperature of 145°C was established in the reaction mixture, which was then maintained for 1 hour. Component 5 was then introduced into the flask, followed by components 6-7, and a temperature of 100°C was established in the reaction mixture. Premixed components 8 and 9 were then rapidly added to the reaction mixture, and the reaction mixture was allowed to exotherm. A temperature of 110°C was established, and the reaction mixture was maintained for 1 hour. After maintenance, the contents of the flask were discarded and cooled to room temperature.

[0149] Table 7. Components used in the preparation of resin system III

[0150]

[0151] 1 EPON 828 is available from Hansen Corporation.

[0152] 2 See the synthesis of crosslinking agent III above.

[0153] 3 Available from Huntsman or Air Products.

[0154] Resin System IV: Resin System for Example 25

[0155] Crosslinker IV was prepared as follows: A blocked polyisocyanate crosslinker suitable for electrodepositable coating resins was prepared by adding components 2 and 3, listed in Table 8 below, to a flask set to total reflux under stirring under nitrogen. The contents of the flask were heated to 35°C, and component 1 was added dropwise, causing the temperature to rise due to the exothermic reaction and remain below 100°C. After the addition of component 1 was complete, a temperature of 100°C was established in the reaction mixture, and the reaction mixture was maintained at this temperature until no residual isocyanate was detected by IR spectroscopy. Components 4 and 5 were then added, and the reaction mixture was stirred at 100°C for 30 minutes. The mixture was then removed from the flask and allowed to cool to ambient temperature.

[0156] Table 8. Components used in the preparation of crosslinking agent IV

[0157] serial number Components Parts by weight (grams) 1 <![CDATA[Polymethylene diphenyl diisocyanate 1 > 402.00 2 K Kat XK 620 (Zinc Amidone) 1.04 3 <![CDATA[Triethylene glycol monoethyl ether 2 > 534.69 4 Butylcarbidol formaldehyde 3.60 5 Bisphenol A–ethylene oxide adduct (1 / 6 molar ratio BPA / EtO) 39.60

[0158] 1 Rubinate M is available from Huntsman Corporation.

[0159] 2 Available from Aldrich.

[0160] Preparation of cationic amine-functionalized polyepoxide-based resins (Resin System IV). The cationic amine-functionalized polyepoxide-based polymeric resins suitable for formulating electrodepositable coating compositions were prepared as follows: Components 9-4 listed in Table 1 below were combined in a flask set to total reflux under stirring under nitrogen. The mixture was heated to 130°C and allowed to exotherm (up to 175°C). A temperature of 145°C was established in the reaction mixture, which was then maintained for 1 hour. Component 5 was then introduced into the flask, followed by components 6-7, and a temperature of 100°C was established in the reaction mixture. Premixed components 8 and 9 were then rapidly added to the reaction mixture, and the reaction mixture was allowed to exotherm. A temperature of 110°C was established, and the reaction mixture was maintained for 1 hour. After maintenance, the contents of the flask were discarded and cooled to room temperature.

[0161] Table 9. Components used in the preparation of resin system IV

[0162]

[0163] 1 EPON 828 is available from Hansen Corporation.

[0164] 2 See the synthesis of crosslinking agent IV above.

[0165] 3 Available from Huntsman or Air Products.

[0166] Resin System V: Resin system for Example 26

[0167] Preparation of Crosslinking Agent V: A blocked polyisocyanate crosslinking agent suitable for electrodepositable coating resins was prepared as follows. Components 2 and 3, listed in Table 10 below, were added to a flask set to total reflux under nitrogen atmosphere. The contents of the flask were heated to 35°C, and component 1 was added dropwise until the temperature rose due to the exothermic reaction and remained below 100°C. After the addition of component 1 was complete, a temperature of 100°C was established in the reaction mixture, and the reaction mixture was maintained at this temperature until no residual isocyanate was detected by IR spectroscopy. Components 4 and 5 were then added, and the reaction mixture was stirred at 100°C for 30 minutes. The mixture was then removed from the flask and allowed to cool to ambient temperature.

[0168] Table 10. Components used to prepare crosslinking agent V

[0169] serial number Components Parts by weight (grams) 1 <![CDATA[Polymethylene diphenyl diisocyanate 1 > 361.80 2 K Kat XK 620 (Zinc Amidone) 1.02 3 <![CDATA[Triethylene glycol monobutyl ether 2 > 556.96 4 Butylcarbidol formaldehyde 3.24 5 Bisphenol A–ethylene oxide adduct (1 / 6 molar ratio BPA / EtO) 35.64

[0170] 1 Rubinate M is available from Huntsman Corporation.

[0171] 2 Available from Aldrich

[0172] Preparation of cationic amine-functionalized polyepoxide-based resins (resin system V). The cationic amine-functionalized polyepoxide-based polymeric resins suitable for formulating electrodepositable coating compositions were prepared as follows: Components 11-4 listed in Table 1 below were combined in a flask set to total reflux under stirring under nitrogen. The mixture was heated to 130°C and allowed to exotherm (up to 175°C). A temperature of 145°C was established in the reaction mixture, which was then maintained for 1 hour. Component 5 was then introduced into the flask, followed by components 6-7, and a temperature of 100°C was established in the reaction mixture. Premixed components 8 and 9 were then rapidly added to the reaction mixture, and the reaction mixture was allowed to exotherm. A temperature of 110°C was established, and the reaction mixture was maintained for 1 hour. After maintenance, the contents of the flask were discarded and cooled to room temperature.

[0173] Table 11. Components used to prepare resin system V

[0174]

[0175] 1 EPON 828 is available from Hansen Corporation.

[0176] 2 See the above section on the synthesis of crosslinking agent V.

[0177] 3 Available from Huntsman or Air Products.

[0178] Resin System VI: Resin System for Example 27

[0179] Crosslinker VI was prepared as follows: A blocked polyisocyanate crosslinker (crosslinker V) suitable for electrodepositable coating resins was prepared. Components 2 and 3, listed in Table 12 below, were added to a flask set to total reflux under nitrogen atmosphere with stirring. The contents of the flask were heated to 35°C, and component 1 was added dropwise, causing the temperature to rise due to the exothermic reaction and remain below 100°C. After the addition of component 1 was complete, a temperature of 100°C was established in the reaction mixture, and the reaction mixture was maintained at this temperature until no residual isocyanate was detected by IR spectroscopy. Components 4 and 5 were then added, and the reaction mixture was stirred at 100°C for 30 minutes. The mixture was then removed from the flask and allowed to cool to ambient temperature.

[0180] Table 12. Components used to prepare crosslinking agent VI

[0181] serial number Components Parts by weight (grams) 1 <![CDATA[Polymethylene diphenyl diisocyanate 1 > 402.00 2 K Kat XK 620 (Zinc Amidone) 1.03 3 Eastman EEH (Ethylene Glycol 2-Ethylhexyl Ether) 522.84 4 Butylcarbidol formaldehyde 3.60 5 Bisphenol A–ethylene oxide adduct (1 / 6 molar ratio BPA / EtO) 39.60

[0182] 1 Rubinate M is available from Huntsman Corporation.

[0183] 2 Eastman EEH is available from Eastman Chemical Company.

[0184] Preparation of cationic amine-functionalized polyepoxide-based resins (resin system VI). The cationic amine-functionalized polyepoxide-based polymeric resins suitable for formulating electrodepositable coating compositions were prepared as follows: Components 13-4 listed in Table 1 below were combined in a flask set to total reflux under nitrogen stirring. The mixture was heated to 130°C and allowed to exotherm (up to 175°C). A temperature of 145°C was established in the reaction mixture, which was then maintained for 1 hour. Component 5 was then introduced into the flask, followed by components 6-7, and a temperature of 100°C was established in the reaction mixture. Premixed components 8 and 9 were then rapidly added to the reaction mixture, and the reaction mixture was allowed to exotherm. A temperature of 110°C was established, and the reaction mixture was maintained for 1 hour. After maintenance, the contents of the flask were discarded and cooled to room temperature.

[0185] Table 13. Components used to prepare resin system VI

[0186]

[0187]

[0188] 1 EPON 828 is available from Hansen Corporation.

[0189] 2 See example crosslinker VI above.

[0190] 3 Available from Huntsman or Air Products.

[0191] Resin System VII: Resin System for Examples 28 and 29

[0192] Preparation of Crosslinking Agent VII: A blocked polyisocyanate crosslinking agent suitable for electrodepositable coating resins was prepared as follows. Components 14-5 listed in Table 2 below were mixed in a flask set to total reflux under nitrogen atmosphere with stirring. The mixture was heated to 35°C, and component 1 was added dropwise such that the temperature increased due to the exothermic reaction and was maintained below 100°C. After the addition of component 1 was complete, a temperature of 110°C was established in the reaction mixture, and the reaction mixture was maintained at this temperature until no residual isocyanate was detected by IR spectroscopy. Component 6 was then added, and the reaction mixture was stirred at 100°C for 30 minutes, then removed from the flask and allowed to cool to ambient temperature.

[0193] Table 14. Components used in the preparation of crosslinking agent VII

[0194] serial number Components Parts by weight (grams) 1 Polymethylene diphenyl diisocyanate 1340.00 2 K Kat XK 620 (Zinc Amidone) 2.77 3 Triethylene glycol monomethyl ether 1149.40 4 <![CDATA[Polyethylene glycol 400 1 > 600.00 5 Butylcarbidol formaldehyde 12.00 6 Bisphenol A–ethylene oxide adduct (1 / 6 molar ratio BPA / EtO) 132.00

[0195] 1 Polyethylene glycol 400 is available from Aldrich.

[0196] Preparation of cationic amine-functionalized polyepoxide-based resins (resin system X). The cationic amine-functionalized polyepoxide-based polymeric resins suitable for formulating electrodepositable coating compositions were prepared as follows: Components 15-4 listed in Table 1 below were combined in a flask set to total reflux under nitrogen stirring. The mixture was heated to 130°C and allowed to exotherm (up to 175°C). A temperature of 145°C was established in the reaction mixture, which was then maintained for 2 hours. Components 5-6 were then introduced into the reaction mixture, and a temperature of 110°C was established. Components 7-9 were then rapidly added to the reaction mixture, and the reaction mixture was allowed to exotherm. A temperature of 121°C was established in the reaction mixture, which was then maintained for 1 hour. After maintenance, the heat source was removed from the reaction mixture, and the contents of the flask were poured into a container and allowed to cool.

[0197] Table 15. Components used in the preparation of resin system VII

[0198]

[0199]

[0200] 1 See the synthesis of crosslinking agent VII above.

[0201] Examples of electrodepositable coating compositions

[0202] Sources of additives and chemicals used in formulation: Chemicals used in the formulation of the electrophoretic coating bath were obtained from various suppliers. MAZON 1651 (butyl carbitol formaldehyde or diethylene glycol monobutyl ether formaldehyde adduct) (98% purity), i.e., a plasticizer, was commercially available from BASF Corporation. Ethylene glycol monobutyl ether (butyl cellosolve) was commercially available from Millipore Signa / Sigma-Aldrich Corporation. The following solvents were obtained from Dow Chemical Company at 98% purity: Dowanol PM, butyl carbitol, and Dowanol PNB glycol ether (Propasol B). Triethylene glycol monomethyl ether (TGME), triethylene glycol monoethyl ether (TGEE), and triethylene glycol monobutyl ether (TGBE) were all obtained from Sigma-Aldrich Corporation at 98% purity. Phosphoric acid (85 wt.% active in water) was obtained from PPG Industries, trisodium phosphate dodecahydrate (98+% purity) from Acros Organics, and monosodium phosphate dihydrate (98+% purity) from AlfaAesar. Sulfamic acid was obtained from PPG Industries. Citric acid, glacial acetic acid (99.7% purity), and oxalic acid (technical grade, 90% purity) were all obtained from Fisher Scientific.

[0203] Evaluation of bath stability of highly colored electrophoretic coatings

[0204] Comparative Example 1 with High Coloration: Clay (390.0 g, ASP 200 available from BASF) was added to Resin I (800.0 g), and mixing was initiated in a metal beaker at 25°C under high shear (2500 RPM, using a 1.5-inch Cowles blade) for 10 minutes. The temperature of the container was not controlled during this process. E6278I (21.4 g, dibutyltin dioxide paste available from PPG), Dynasylan 4148 (7.8 g, available from Evonik Industries), and diethylene glycol monobutyl ether-formaldehyde adduct (10.4 g) were added to the resin / clay mixture. High-shear mixing continued for an additional 50 minutes. A portion of this clay / resin paste (80%, 983.0 g) was added to a solution of sulfamic acid (12.5 g) dissolved in deionized water (413.8 g). This material was mixed for over twenty minutes. The resulting 1K high-solids feed had a P:B ratio of 0.75:1 and 54 wt.% bath solids. This material was diluted with deionized water to a total weight of 3800 g, with a final bath solids content of 20%. The final bath had a pH of 5.01 and a conductivity of 868 μS / cm. For each example, pH and conductivity were measured using a Thermo Fisher Scientific Orion Star A215 benchtop pH / conductivity meter equipped with an Orion 013005MD conductivity cell and an Orion 8157BNUMD Ross Ultra pH / ATC transistor, all commercially available from Thermo Fisher Scientific, Inc.

[0205] Compare with A This electrophoretic coating is available from PPG under the name Powercron 590-534 as a 1K feedstock (product code: CF590-534). Deionized water (2312.6 g) was added to 1487.4 g of CF590-534 with stirring for one hour. This material was then used for electrophoretic coating of the panel. The P:B ratio of this coating is 0.15:1.0. Control A was used according to the technical bulletin.

[0206] Bath stability assessmentA CRS panel pretreated with zinc phosphate (C700 / DI; part number: 28630, available from ACT, Hillsdale, MI.) was cut in half to obtain a 4” x 6” panel. Then, 0.25 inches were removed from each side of the panel, resulting in a 3.5” x 6” panel. This panel was then bent into an “L” shape to obtain a 4” vertical surface and a 2” horizontal surface. This panel was immersed in an electrophoretic coating and agitation was stopped. After standing in an unstirred bath for three minutes, electrodeposition began. The electrodeposable coating was applied using a DC-powered rectifier (Xantrax XFR600-2, Elkhart, Indiana, or Sorensen XG 300-5.6, Ameteck, Berwyn, Pennsylvania). The target film thickness on the vertical surface was 0.5 to 0.7 mils (12.7 to 17.8 micrometers). For a DFT of 25.4 micrometers, this film thickness was deposited using voltage / temperature / current conditions (two-minute conditions), but for one minute. The exact coating conditions for each coating are shown in Table 16. After the panels were electrophoretically coated, they were rinsed with deionized water and baked in an electric oven (Despatch LFD-1-42 type) at 350°F for 30 minutes. The roughness of the horizontal and vertical surfaces was measured using a Precision Surtronic 25 surface photometer, available from Taylor Hobson. The instrument was referenced using a 3-inch silicon wafer (product number 16013), available from Ted Pella Inc., which showed a roughness of 1.0 ± 0.7 microinches after 10 repeated measurements.

[0207] Table 16. Comparison of electrodeposition conditions and cured film roughness

[0208]

[0209] Because electrodeposable coating compositions are typically applied to components with complex shapes and both horizontal and vertical surfaces, comparable roughness is desirable, regardless of the orientation of the surfaces to be coated. The significant difference in vertical and horizontal surface roughness in Comparative Example 1, which uses silane as a dispersant and exhibits high coloration, indicates a lack of bath stability and an inability to provide performance close to that of standard electrodeposable coating compositions, as shown in Control A.

[0210] Example of corrosion testing using Resin II

[0211] Resin System II was prepared to avoid the need for ketamine in the resin. Excessive MIBK in the final electrophoretic coating formulation will also increase the measured volatile organic compound (VOC) content. Resin II was designed as a high-solids material with the lowest VOC content.

[0212] 9100HE (Control B): This material is available from PPG Industries under the product name Powercron 686-470 as a 1K import. This coating was applied according to PPG's published process references and product data sheets. The P / B ratio of this electrophoretic coating is 0.1:1.0.

[0213] Compare Examples 2 to 7 Examples 2 through 7 were prepared according to the following general procedure. 450 g of Resin II was placed in a stainless steel beaker (1200 mL) and heated to 85°C using a thermocouple (J-KEM Technology 410A) and a heating mantle. The resin was stirred at 2500 RPM using a 1.5-inch Coulomb blade powered by a Fawcett pneumatic motor (103A). The following components were added in the listed order. Specific amounts not specified in the text are listed in Table 17. Butyl cellosolve (72.0 g) was added to the resin and mixed for five minutes. Next, clay (available from BASF as ASP 200 or ASP 900) was added within five minutes, followed by Dynasylan 4148 (1.7 g) and deionized water (17.0 g), available from Evonik. This mixture was stirred for one hour, and the degree of dispersion was then determined using a Hegman gauge. A minimum reading of 5 was required for adequate dispersion.

[0214] Table 17. Electrophoretic coating baths P:B and the amount of clay added in Examples 2 to 7.

[0215] Example Bath P:B ratio clay Mass of clay (g) Comparison 2 0.75:1 ASP 900 337.5 Comparison 3 0.4:1.0 ASP 900 180.0 Comparison 4 0.2:1.0 ASP 900 90.0 Compare 5 0.1:1.0 ASP 900 45.0 Compare 6 0.75:1.0 ASP 200 337.5 Compare 7 0.2:1.0 ASP 200 90.0

[0216] For the dispersion step, clay / resin II paste is added to a mixture of acid and water. For Examples 2 to 7, 80% (by weight) of the clay / resin II dispersion is added to another stainless steel beaker containing deionized water maintained at 25°C and sulfamic acid (4.7 g) to obtain a feed with a high solids content of 1K. The mass, amount of water, and droplet solids content, representing 80% by weight, are reported in Table 18.

[0217] Table 18. Material quality used to prepare high solids content 1K formulations for Examples 2 to 7.

[0218]

[0219] For Examples 2 through 7, an electrophoretic coating bath with a 20% solids content was prepared by adding deionized water to a high-solids-content 1K feed, with sufficient deionized water added to bring the total bath weight to 3800 g. Half of the water reported in Table 18 was added, followed by the solder paste, and finally the remaining water. A tin catalyst was added using E6278I (dibutyltin oxide [DBTO] paste available from PPG Industries, containing 7.2 wt.% DBTO) to provide 0.7 wt% Sn loading on the resin solids.

[0220] Controls B and Comparative Examples 2 through 7 were used for electrophoretic coating of zinc phosphate CRS. Panels were cut in half to a size of 4” × 6”. Electrodepositable coatings were applied using a DC-powered rectifier (Xantrax XFR600-2, Elckhart, Indiana or Sorensen XG 300-5.6, Ametek, Berwin, PA) at 90℉. After electrophoretic coating, the panels were rinsed with deionized water and baked in an oven (Despatch LFD-1-42) at 350℉ for 30 minutes. The target dry film thickness was 25.4 micrometers (1 mil). Precise deposition conditions for each run are shown in Table 19. Three panels coated with each electrophoretic coating composition were scribed down to the metal substrate in a 3-inch vertical line from the center of the panel. The panels were then placed in a GMW14872 test for a total of 40 cycles (days). After testing, the panels were rinsed with deionized water and allowed to air dry. The amount of corrosion in the scribing area is then measured and reported in Table 19. Scibing creep refers to the area of ​​paint loss around the scribing area caused by corrosion or peeling (e.g., from affected paint to affected paint).

[0221] Table 19. Electrodeposition conditions and corrosion results for Control B and Examples 2 to 7

[0222] Example Voltage (V) Electric current (amperes) Time (minutes) Streak creep (mm) Compare with B 200V 0.5 amperes 1.5 minutes 6.2 Comparison 2 115V 0.5 amperes 1.5 minutes 4.5 Comparison 3 75V 0.5 amperes 1.5 minutes 3.2 Comparison 4 50V 0.5 amperes 1.5 minutes 5.5 Compare 5 50V 0.5 amperes 1.5 minutes 6.1 Compare 6 265V 0.5 amperes 1.5 minutes 3.5 Compare 7 50V 0.5 amperes 1.5 minutes 5.6

[0223] As described above, compared to control composition B, the modified resins using the silane dispersants of comparative examples 2 to 7 and the higher coloring load produced coatings that maintained or improved corrosion resistance. The stability of these compositions was further investigated.

[0224] Pump stability of reconstituted paint

[0225] Comparison Example 8680 g of Resin II was placed in a 2-liter stainless steel beaker and heated to 85°C using a thermocouple and heating mantle. The resin was stirred at 2500 RPM using a 1.5-inch Coles blade powered by a Fawcett pneumatic motor (Model 103A). The following ingredients were added in the listed order. 98.9 g of Dowanol PM was added to the resin and mixed for five minutes. Next, 340.0 g of ASP 200 was added over five minutes, followed by Dynasylan 4148 (5.1 g) and deionized water (51.0 g). This mixture was stirred for one hour and the degree of dispersion was then determined using a Hergmann meter. A minimum reading of 5 was required for adequate dispersion. For the dispersion step, the clay / resin II paste was added to the mixture of acid and water. For Example 8, a portion of the clay / resin dispersion (822.5 g) was added to another stainless steel beaker containing deionized water (613.2 g) and aminosulfonic acid (6.2 g) maintained at 60°C to obtain a 1K feed with a solids content of 55 wt.%. An electrophoretic coating bath with a solids content of 20 wt.% was prepared by adding deionized water to the high-solids 1K feed to bring the total bath weight to 3800 g. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 through 7. The final bath pH was 4.87, and the conductivity was 277 μS / cm.

[0226] Comparison Example 9: 580 g of Resin II was placed in a 2-liter stainless steel beaker and heated to 85°C using a thermocouple and heating mantle. The resin was stirred at 2500 RPM using a 1.5-inch Coles blade powered by a Fawcett pneumatic motor (Model 103A). The following ingredients were added in the listed order. 84.4 g of Dowanol PM was added to the resin and mixed for five minutes. Next, 435.0 g of ASP 200 was added over five minutes, followed by Dynasylan 4148 (6.5 g) and deionized water (65.3 g). This mixture was stirred for one hour, and the degree of dispersion was then determined using a Hergmann meter. A minimum reading of 5 was required for adequate dispersion. For the dispersion step, the clay / resin II paste was added to the mixture of acid and water. For Example 9, a portion of the clay / resin dispersion (819.8 g) was added to another stainless steel beaker containing deionized water (592.1 g) and aminosulfonic acid (5.3 g) maintained at 60°C to obtain a 1K feed with a solids content of 55 wt.%. An electrophoretic coating bath with a solids content of 20 wt.% was prepared by adding deionized water to the high-solids 1K feed to bring the total bath weight to 3800 g. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 through 7. The final bath pH was 5.17, and the conductivity was 285 μS / cm.

[0227] Bath stability assessment For Comparative Examples 8 and 9, the L-panel was coated in the same manner as in Comparative Example 1. For coating the L-panel, the electrodeposition conditions for Example 8 were 200V / 90°F / 60 seconds / 0.5 Amperes, and for Example 9, they were 250V / 90℉ / 60 seconds / 0.5 Amperes. The roughness of the horizontal and vertical surfaces was measured using a Precision Surtronic 25 surface photometer, available from Taylor Hopson, and is reported in Table 20.

[0228] Control A (3800g bath) and Example 10 (3800g bath) were pumped at 95℉ for 16 hours using a Little Giant 4-MD magnetically driven pump (SKU 582002, 1 / 12HP, 115V). After pumping, the materials were passed through a 335-mesh sieve. The pumped material was then used to coat panel L. To pass the pump test, less than 1g of material must be collected on the 335-mesh sieve, and the appearance of the coating before and after pumping must be similar. Table 20 summarizes the results of the pump stability test.

[0229] Table 20. Effects of Resin II and Silane Dispersant on Bath Stability

[0230]

[0231] 1 The coated panel of Comparative Example 9 has a very poor appearance, with many pits and microbubbles in the cured film.

[0232] Modified resins with silane pigment dispersants do not result in acceptable stability of compositions capable of cationic electrodeposition.

[0233] Dispersant modification of highly colored electrophoretic coatings

[0234] Example 10 and comparison examples 11 and 12These electrophoretic coating baths were prepared according to the following general procedure. 600 g of Resin II was placed in a 2-liter stainless steel beaker and heated to 85°C using a thermocouple and heating mantle. The resin was stirred at 2500 RPM using a 1.5-inch Coulomb blade powered by a Fawcett pneumatic motor (Model 103A). The following ingredients were added in the listed order. Specific amounts not specified in the text are listed in Table 21. Butyl cellosolve (48.0 g) and Dowanol PM (48.0 g) were added to Resin II and mixed for five minutes. Then, the phosphate derivative was added to the diluted resin and mixed for five minutes. Next, ASP 200 (240.0 g, available from BASF) was added over five minutes. This mixture was milled for one hour, and the degree of dispersion was then determined using a Hergmann meter. A minimum reading of 5 was required for adequate dispersion. The neutralization of the clay / Resin II paste with sulfamic acid is described below for each example.

[0235] Table 21. Phosphate Derivative Dispersants

[0236]

[0237] 1 Source: Chemistry the Central Science, 12th edition. pKa values ​​are derived from Ka values ​​in Appendix D.

[0238] Example 10: 8.1 g of phosphoric acid (85 wt.% active) was used as a dispersant. A portion (755.3 g, 80% of the total weight) of the clay / resin paste was added to a mixture of water (325.0 g) and aminosulfonic acid (6.3 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. For Example 10, the electrodeposition conditions for coating the L panel were 225 volts / 60 seconds / 90℉ / 0.5 amps, with no voltage ramp. The roughness of the cured L panel is listed in Table 22.

[0239] Comparison Example 11: 10.8 g of sodium dihydrogen phosphate dihydrate was used as a dispersant. A portion (757.4 g, 80% of the total weight) of the clay / resin II paste was added to a mixture of water (327.3 g) and aminosulfonic acid (6.3 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed, but water could not be incorporated into the 1K feed. No feasible electrophoretic coating bath was formulated using the composition of Example 11. No panels were electrophoretically coated.

[0240] Comparison Example 12: 25.2 g of trisodium phosphate dodecahydrate was used as a dispersant. A portion (769.0 g, 80% of the total weight) of the clay / resin paste was added to a mixture of water (332.2 g) and aminosulfonic acid (6.3 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. However, neutralization of the clay / resin paste was ineffective, and poor paste incorporation was observed in acidic water. No feasible electrophoretic coating bath was prepared using the composition of Example 12. No panels were electrophoretically coated.

[0241] Table 22. Summary of the effects of phosphate derivatives on the stability of electrophoretic coating baths

[0242]

[0243] These examples demonstrate that the pKa of the first acidic proton of a dispersant can affect the stability of the resulting electrodepositable coating composition. As shown in Table 22, Example 10 contains phosphoric acid as a dispersant with a first acidic proton pKa of 2.12 and produces a stable composition. In contrast, Comparative Example 11 contains sodium dihydrogen phosphate dihydrate with a first acidic proton pKa of 7.21 and does not produce a viable composition. Similarly, Comparative Example 12 contains trisodium phosphate dodecahydrate, which does not have an acidic proton, and does not produce a viable composition.

[0244] Evaluation of shear stress resistance (pump stability) of high P / B electrophoretic coatings

[0245] Control A (3800g bath) and Example 10 (3800g bath) were pumped at 95℉ for 16 hours using a Little Giant 4-MD magnetically driven pump (SKU 582002, 1 / 12HP, 115V). After pumping, the coatings were passed through a 335-mesh sieve by gravity. The pumped material was then used to coat panel L as described in Comparative Example 1. To pass the pump test, less than 1g of material must be collected on the sieve, and the appearance of the deposited film of the coating before and after pumping must be similar. Table 23 summarizes the results of the pump stability test.

[0246] Table 23. Summary of the effects of phosphate derivatives on the stability of electrophoretic coating baths

[0247]

[0248] The results in Table 23 show that Example 10, which contains phosphoric acid as a dispersant, produces a composition with improved pump stability compared to Comparative Example 8, which contains silane as a dispersant (see Table 2). Furthermore, these results also demonstrate a significant improvement in the L-panel appearance compared to the highly colored composition of Comparative Example 8, given Example 10. These results indicate that the pKa of the first acidic proton of the dispersant can indicate improved stability of layered silicate pigments such as kaolin clay.

[0249] Comparison of bath stability of dispersants with different pKa

[0250] Other acid dispersants with pKa values ​​indicated in Table 24 below were also investigated as potential dispersants.

[0251] Table 24. Acid strength of dispersants

[0252]

[0253] 1 Source: *Kirk-Othmer Encyclopedia of Chemical Technology*, "Sulfamic Acids and Sulfamates". pKa values ​​are derived from K at 25°C. a .

[0254] 2 Source: Chemistry: Central Science, 12th edition. pKa values ​​are from Ka values ​​at 25°C in Appendix D.

[0255] Compare Examples 13 and 16 with Examples 14 and 15 These electrophoretic coating baths were prepared according to the following general procedure. Resin II was loaded into a 2-liter stainless steel beaker and heated to 85°C using a thermocouple and heating mantle. The resin was stirred at 2500 RPM using a 1.5-inch Coulomb blade powered by a Fawcett pneumatic motor (Model 103A). The following ingredients were added in the listed order. Specific amounts not specified in the text are listed in Table 25. Butyl cellosolve was added to the resin and mixed for five minutes. Then, the dispersant was added to the diluted resin and mixed for five minutes. Next, ASP 200 kaolin clay was added over five minutes. This mixture was ground for one hour, and the degree of dispersion was then determined using a Hergmann meter. A minimum reading of 5 was required for adequate dispersion. The neutralization of acidic water in the clay / resin II paste is described in detail below for each example.

[0256] Table 25. Amount of materials added for preparing Examples 13 to 16

[0257] Comparative Example 13 Example 14 Example 15 Comparative Example 16 Electrophoretic coating bath P:B ratio 0.75:1.0 0.4:1.0 0.4:1 0.75:1.0 dispersant Aminosulfonic acid oxalic acid Citric acid Acetic acid Mass of dispersant (g) 6.1g 13.2g 13.2g 3.7g Mass of Resin II (g) 550.0g 600.0g 600.0g 520.0g diluent Butyl cellosolve / water Butyl cellosolve Butyl cellosolve Butyl cellosolve / water Mass of diluent (g) 88.0g / 60.5g 96.0g 96.0g 83.7g / 19.5g Quality of ASP 200 clay 412.5g 240.0g 240.0g 390.0g

[0258] Comparison Example 13: A portion of 408.9 g (80% of the total weight) of the clay / resin II paste was added to a mixture of water (144.9 g) and aminosulfonic acid (2.6 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. Deionized water was added to this 1K feed, but water could not be incorporated into the 1K feed. No feasible electrophoretic coating bath was formulated using the composition of Example 13. No panels were electrophoretically coated.

[0259] Example 14: A portion of the clay / resin paste, 759.4 g (80% of the total weight), was added to a mixture of water (328.1 g) and aminosulfonic acid (6.3 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner described in Examples 2 through 7. The pH of this composition was 3.3, and the conductivity was 982 μS / cm. As previously described, this composition was used for electrophoretic coating of L-panels. The electrodeposition parameters were 140 V / 60 s / 90°F / 0.5 A, with no voltage ramp. The roughness of the cured L-panels is listed in Table 26. The shear stability of this composition (pump-free test) was not evaluated.

[0260] Example 15: A portion of the clay / resin paste, 759.4 g (80% of the total weight), was added to a mixture of water (328.1 g) and aminosulfonic acid (6.3 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner described in Examples 2 through 7. The pH of this composition was 3.0, and the conductivity was 1037 μS / cm. As previously described, this composition was used for electrophoretic coating of L-panels. The electrodeposition parameters were 100 volts / 60 seconds / 90°F / 0.5 amperes, with no voltage ramp. The roughness of the cured L-panels is listed in Table 26. The shear stability of this composition was not tested (no-pump test).

[0261] Comparison Example 16:A portion of 813.5 g (80% of total weight) of the clay / resin II paste was added to a mixture of water (329.4 g) and aminosulfonic acid (7.1 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. Adding deionized water to this 1K feed; however, upon standing, a significant amount of clay detached from the dispersion. The stable composition of Example 16 could not be formulated. No panels were electrophoretically coated.

[0262] Table 26. Amount of materials added for preparing Examples 11 to 14

[0263]

[0264] The results in Table 26 indicate that dispersants with a first pKa between about 1.1 and about 4.6 provide better antisettling properties than dispersants with a higher (e.g., acetic acid, sodium dihydrogen phosphate, silane) or lower (e.g., aminosulfonic acid) pKa.

[0265] Evaluation of the effect of dilution solvent on bath stability

[0266] Examples 17 to 24 These electrophoretic coating compositions were prepared according to the following general procedure. Resin II was loaded into a 2-liter stainless steel beaker and heated to 85°C using a thermocouple and heating mantle. The resin was stirred at 2500 RPM using a 1.5-inch Coulomb blade powered by a Fawcett pneumatic motor (Model 103A). The following ingredients were added in the listed order. Specific amounts not specified in the text are listed in Table 27. A diluent was added to the resin, and the mixture was allowed to mix for five minutes. Then, the dispersant (phosphoric acid) was added to the diluted resin, and the mixture was allowed to mix for five minutes. Next, ASP 200 kaolin clay was added over five minutes. This mixture was ground for one hour, and the degree of dispersion was then determined using a Hergmann meter. A minimum reading of 5 was required for adequate dispersion. The neutralization of the resin / clay II paste with acidic water is described in detail below for each example.

[0267] Table 27. Amount of materials added for preparing Examples 17 to 23

[0268]

[0269] Example 17:A portion of 755.3 g (80% of total weight) of the clay / resin II paste was added to a mixture of water (325.0 g) and aminosulfonic acid (6.3 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. The pH of this composition was 3.4, and the conductivity was 620 μS / cm. The L panel was coated in the same manner as in Comparative Example 1. The electrodeposition parameters for the L panel were 250 V / 60 s / 90°F / 0.5 A, with no voltage ramp. The roughness of the cured L panel is listed in Table 28.

[0270] Example 18: A portion of 812.9 g (70% of total weight) of the clay / resin II paste was added to a mixture of water (668.0 g) and aminosulfonic acid (6.4 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 55 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. The pH of this composition was 4.23, and the conductivity was 530 μS / cm. The L panel was coated in the same manner as in Comparative Example 1. The electrodeposition parameters were 298 V / 60 s / 90℉ / 0.5 A, with no voltage ramp. The roughness of the cured L panel is listed in Table 28.

[0271] Example 19: A portion of 755.3 g (80% of total weight) of the clay / resin II paste was added to a mixture of water (325.0 g) and aminosulfonic acid (6.3 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. The pH of this composition was 3.2, and the conductivity was 595 μS / cm. The L panel was coated in the same manner as in Comparative Example 1. The electrodeposition parameters were 250 volts / 60 seconds / 90℉ / 0.5 amperes, with no voltage ramp. The roughness of the cured L panel is listed in Table 28.

[0272] Example 20:A portion of 763.9 g (70% of total weight) of clay / resin II paste was added to a mixture of water (328.7 g) and aminosulfonic acid (6.4 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. The pH of this composition was 3.59, and the conductivity was 741 μS / cm. The L panel was coated in the same manner as in Comparative Example 1. The electrodeposition parameters were 260 V / 60 s / 90 °F / 0.5 A, with no voltage ramp. The roughness of the cured L panel is listed in Table 28.

[0273] Example 21: A portion of the clay / resin II paste, 763.9 g (70% of the total weight), was added to a mixture of water (328.7 g) and aminosulfonic acid (6.4 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. The pH of this composition was 3.71, and the conductivity was 799 μS / cm. The L panel was coated in the same manner as in Comparative Example 1. The electrodeposition parameters were 140 V / 60 s / 90 °F / 0.5 A, with no voltage ramp. The roughness of the cured L panel is listed in Table 28.

[0274] Example 22: A portion of 755.3 g (80% of total weight) of the clay / resin II paste was added to a mixture of water (325.0 g) and aminosulfonic acid (5.5 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. The pH of this composition was 3.9, and the conductivity was 658 μS / cm. The L panel was coated in the same manner as in Comparative Example 1. The electrodeposition parameters were 250 volts / 60 seconds / 90℉ / 0.5 amperes, with no voltage ramp. The roughness of the cured L panel is listed in Table 28.

[0275] Example 23:A portion of 786.5 g (70% of total weight) of clay / resin II paste was added to a mixture of water (647.7 g) and aminosulfonic acid (6.2 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 55 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. The pH of this composition was 4.19, and the conductivity was 504 μS / cm. The L panel was coated in the same manner as in Comparative Example 1. The electrodeposition parameters were 298 V / 60 s / 90℉ / 0.5 A, with no voltage ramp. The roughness of the cured L panel is listed in Table 28.

[0276] Pump stability test: Examples 17 to 23 (3800g bath) were pumped at 95℉ for 16 hours using a Little Giant 4-MD magnetically driven pump (SKU 582002, 1 / 12HP, 115V). After pumping, the materials were passed through a 335-mesh sieve. The pumped material was then used to coat the L panel. To pass the pump test, less than 1g of material must be collected on the 335-mesh sieve, and the appearance of the deposited film of the coating before and after pumping must be similar. Table 28 summarizes the results of the pump stability test.

[0277] Table 28. Summary of the effect of dilution solvent modification on the stability of electrophoretic coating bath

[0278]

[0279] The results in Table 28 indicate that diluents with more hydrophilic groups and shorter alkyl chains generally improve anti-settling behavior (L panel roughness) and improve pump stability (e.g., Dowanol PM and TGME with butyl carbitol and butyl cellosolve).

[0280] Effects of blocking groups on the stability and pH of the final electrophoretic coating bath

[0281] Examples 24 to 27These electrophoretic coating baths were prepared according to the following general procedure. The resin specified in Table 29 was loaded into a stainless steel beaker (2 liters) and heated to 85°C using a thermocouple and heating mantle. The resin was stirred at 2500 RPM using a 1.5-inch Coulomb blade powered by a Fawcett pneumatic motor (Model 103A). The following components were added in the listed order. Specific amounts not specified in the text are listed in Table 29. A diluent was added to the resin, and the mixture was allowed to mix for five minutes. Then, the dispersant (phosphoric acid) was added to the diluted resin, and the mixture was allowed to mix for five minutes. Next, ASP 200 kaolin clay was added over five minutes. This mixture was ground for one hour, and the degree of dispersion was then determined using a Hergmann meter. A minimum reading of 5 was required for adequate dispersion. The neutralization of the resin / clay paste with acidic water is described in detail below for each example.

[0282] Table 29. Amount of materials added for preparing Examples 24 to 27

[0283] Example 24 Example 25 Example 26 Example 27 Electrophoretic coating bath P:B ratio 0.4:1 0.4:1 0.4:1 0.4:1 resin Resin III Resin IV Resin V Resin VI The sealing group in the X-connector TGME TGEE TGBE Eastman EEH Mass of Resin II (g) 600.0g 600.0g 600.0g 600.0g dispersant Phosphoric acid Phosphoric acid Phosphoric acid Phosphoric acid Mass of dispersant (g) 8.1g 8.1g 8.1g 8.1g diluent DowanolPM DowanolPM DowanolPM Dowanol PM Mass of diluent (g) 96.0g 96.0g 96.0g 96.0g ASP 200 quality 240.0g 240.0g 240.0g 240.0g

[0284] Example 24: A portion of 755.3 g (80% of the total weight) of the clay / resin III paste was added to a mixture of water (755.3 g) and aminosulfonic acid (6.3 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. The pH of this composition was 5.34, and the conductivity was 483 μS / cm.

[0285] Example 25: A portion 755.3 g (80% of the total weight) of the clay / resin IV paste was added to a mixture of water (755.3 g) and aminosulfonic acid (6.3 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. The pH of this composition was 3.72, and the conductivity was 342 μS / cm.

[0286] Example 26:A portion 748.0 g (80% of the total weight) of the clay / resin V paste was added to a mixture of water (325.0 g) and aminosulfonic acid (6.2 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. The pH of this composition was 5.02, and the conductivity was 871 μS / cm.

[0287] Example 27: A portion 755.3 g (80% of the total weight) of the clay / resin VI paste was added to a mixture of water (755.3 g) and aminosulfonic acid (6.3 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 70 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner as described in Examples 2 to 7. The pH of this composition was 4.32, and the conductivity was 659 μS / cm.

[0288] Table 30. Effect of blocked alcohol groups in crosslinking agents on final bath pH

[0289]

[0290] The results in Table 30 indicate that the blocking groups of the curing agent may affect the bath pH, ​​which can manipulate bath stability in combination with the dispersant. Materials with lower hydrophobicity (TGME and TGEE) have a maximum pH of at least half a pH unit.

[0291] Example 28523.5 g of Resin VII (as described above) and 126.5 g of Crosslinking Agent VII (as described above) were placed in a 2-liter stainless steel beaker and heated to 85°C using a thermocouple and heating mantle. The resin was stirred at 2500 RPM using a 1.5-inch Coulomb blade powered by a Fawcett pneumatic motor (Model 103A). Dowanol PM (94.3 g), followed by phosphoric acid (85% aqueous solution, 6.1 g) and DI water (74.8 g) were added to Resin VII and mixed for ten minutes. Next, ASP 200 (487.5 g, available from BASF) was added over five minutes. This mixture was ground for one hour and the degree of dispersion was then determined using a Hergmann meter. A minimum reading of 5 was required for adequate dispersion. A portion (918.8 g, 70% of the total weight) of the clay / resin paste was added to a mixture of water (1012.8 g) and aminosulfonic acid (6.12 g) in a large stainless steel beaker to obtain a 1K feed with a solids content of 45 wt.%. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner described in Examples 2 through 7. Butylcarbidol formaldehyde (45.5 g) was then added to the bath, and the bath was allowed to mix with gentle stirring for 24 hours. The final bath had a pH of 5.01 and a P:B ratio of 0.75:1.

[0292] Compare with C This electrophoretic coating is available from PPG under the name POWERCRON 590-534 as a 1K feedstock (product code: CF590-534). Deionized water (2312.6 g) was added to 1487.4 g of CF590-534 with stirring for one hour. This material was then used for electrophoretic coating of the panel. The P:B ratio of this coating is 0.15:1.0. Reference C was used according to the technical bulletin.

[0293] Evaluation of the stability of Example 28 and Control Bath CA CRS panel pretreated with zinc phosphate (C700 part number: 28630, available from ACT, Hillsdale, .M.) was cut in half to obtain a 4” x 6” panel. Then, 0.25 inches were removed from each side of the panel, resulting in a 3.5” x 6” panel. This panel was then bent into an “L” shape to obtain a 4” vertical surface and a 2” horizontal surface. This panel was immersed in an electrophoretic coating and agitation was stopped. After standing in an unstirred bath for three minutes, electrodeposition began. The electrodepositable coating was applied using a DC-powered rectifier (Xantrax XFR600-2, Elckhart, .IN., or Sorensen XG 300-5.6, Ametek, .P., Berwin, .IN.). The target film thickness on the vertical surface was 0.5 to 0.7 mils (12.7 to 17.8 micrometers). For a DFT of 25.4 microns, this film thickness was deposited using voltage / temperature / current conditions (two-minute conditions), but for one minute. The exact coating conditions for each coating are shown in the table below. After the panels were electrophoretically coated, they were rinsed with deionized water and baked in an electric oven (Despatch LFD-1-42 type) at 350℉ for 30 minutes. The roughness of the horizontal and vertical surfaces was measured using a PrecisionSurtronic 25 surface photometer, available from Taylor Hopson. The instrument was referenced using a 3-inch silicon wafer (product number 16013), available from Ted Peller, which yielded a roughness of 1.0 ± 0.7 microns after 10 repeated measurements.

[0294] Table 31. Comparison of electrodeposition conditions and cured film roughness

[0295]

[0296] As demonstrated in highly colored Example 28, a similar vertical to horizontal appearance ratio can be achieved in highly colored systems using a glycol-blocked crosslinking agent. This is desirable because electrodepositable coating compositions are typically applied to parts with complex shapes having both horizontal and vertical surfaces. The appearance should be substantially similar regardless of the orientation of the coated surfaces.

[0297] Example 29In a 2-liter stainless steel beaker, add 428.6 g of Resin VII (as described above) and 40.9 g of Crosslinking Agent VII (as described above), and heat the resin to 85°C using a thermocouple and heating mantle. Stir the resin at 2500 RPM using a 1.5-inch Coulomb blade powered by a Fawcett pneumatic motor (Type 103A). Add phosphoric acid (85% aqueous solution, 3.8 g) to the mixture of Resin VII and Crosslinking Agent VII, followed by DI water (46 g), and mix for ten minutes. Next, add ASP 200 (800.0 g, available from BASF) in 100 g increments. Dowanol PM is added between each ASP 200 increment. The total amount of Dowanol PM added is 120 g. Grind this mixture for one hour. A portion (923.5 g, 70% of the total weight) of the clay / resin paste was added to a mixture of water (482.9 g) and aminosulfonic acid (3.72 g) in a large stainless steel beaker heated to 60°C. Deionized water was added to this 1K feed to obtain a total of 3800 g of electrophoretic coating bath. The 1K feed material was diluted with DI water and solder paste was added in the same manner described in Examples 2 through 7. The final bath had a pH of 5.08 and a P:B ratio of 2.0:1.

[0298] Example 29 shows that the blocking groups of the curing agent may affect the bath pH, ​​which, even at very high pigment loadings, can be used in conjunction with the dispersant to control bath stability.

[0299] Those skilled in the art will understand that, based on the foregoing disclosure, many modifications and variations are possible without departing from the broad inventive concept described and illustrated herein. Therefore, it should be understood that the foregoing disclosure is merely an illustration of various exemplary aspects of this application, and that many modifications and variations can be readily made by those skilled in the art within the spirit and scope of this application and the appended claims.

Claims

1. A cationic electrodepositable coating composition comprising: Cationic electrodeposition adhesives; And layered silicate pigment-dispersed acid complexes, wherein the complexes have anionic charges, and wherein the layered silicate pigments in the layered silicate pigment-dispersed acid complexes include kaolin clay. The dispersed acid in the layered silicate pigment-dispersed acid composite comprises a first acid proton with a pKa of 1.1 to 4.

6. The cationic electrodepositable binder comprises a film-forming polymer containing cationic salt groups, wherein the weight molar ratio of the layered silicate pigment to the dispersing acid is 0.25 to 25 g / mmol. The pigment to binder (P:B) ratio of the layered silicate pigment to the cationic electrodepositable binder is from 0.2:1 to 2.0:

1.

2. The cationic electrodepositable coating composition according to claim 1, wherein the layered silicate pigment in the layered silicate pigment-dispersed acid composite further comprises mica, chlorite, serpentine, talc, or a combination thereof.

3. The cationic electrodepositable coating composition according to any one of the preceding claims, wherein the layered silicate pigment comprises a plate-like layered silicate pigment.

4. The cationic electrodepositable coating composition according to claim 3, wherein the plate-like layered silicate pigment comprises plate-like kaolin clay pigment and optionally further comprises plate-like mica pigment, plate-like chlorite pigment, plate-like serpentine pigment, plate-like talc pigment, or a combination thereof.

5. The cationic electrodepositable coating composition according to claim 1, wherein the dispersing acid comprises a monobasic acid, a polybasic acid, or a combination thereof.

6. The cationic electrodepositable coating composition according to claim 1, wherein the dispersing acid comprises an oxyacid of phosphorus, a carboxylic acid, an oxyacid of sulfur, or a combination thereof.

7. The cationic electrodepositable coating composition according to claim 5, wherein the dispersing acid comprises an oxyacid of phosphorus, a carboxylic acid, an oxyacid of sulfur, or a combination thereof.

8. The cationic electrodepositable coating composition according to any one of claims 1, 2 or 5-7, wherein the dispersing acid comprises phosphoric acid, and the layered silicate pigment-dispersing acid composite comprises a layered silicate pigment-phosphoric acid composite.

9. The cationic electrodepositable coating composition according to any one of claims 1, 2 or 5-7, wherein the dispersive acid is present in an amount of 0.1% to 10% by weight based on the total solid weight of the composition.

10. The cationic electrodepositable coating composition of claim 1, wherein the film-forming polymer containing cationic salt groups comprises active hydrogen functional groups, and the film-forming polymer containing cationic salt groups comprises a film-forming polymer containing active hydrogen and cationic salt groups.

11. The cationic electrodepositable coating composition according to any one of claims 1, 2, 5-7 or 10, wherein the film-forming polymer containing cationic salt groups comprises alkyd resin polymers, acrylic polymers, polyepoxide polymers, polyamide polymers, polyurethane polymers, polyurea polymers, polyester polymers or combinations thereof.

12. The cationic electrodepositable coating composition according to any one of claims 1, 2, 5-7 or 10, wherein the film-forming polymer containing cationic salt groups comprises alkyd resin polymers, acrylic polymers, polyamide polymers, polyurethane polymers, polyurea polymers, polyether polymers, polyester polymers or combinations thereof.

13. The cationic electrodepositable coating composition according to claim 1 or 10, wherein the film-forming polymer containing cationic salt groups is at least partially neutralized with a neutralizing acid.

14. The cationic electrodepositable coating composition according to any one of claims 1, 2, 5-7 or 10, wherein the cationic electrodepositable binder further comprises a curing agent.

15. The cationic electrodepositable coating composition of claim 14, wherein the curing agent comprises at least partially blocked polyisocyanates, amino plastic resins, phenolic plastic resins, or combinations thereof.

16. The cationic electrodepositable coating composition of claim 15, wherein the curing agent comprises at least partially blocked polyisocyanate, said at least partially blocked polyisocyanate being blocked with a blocking agent comprising the following structure: R1 and R2 are each hydrogen, or one of R1 and R2 is hydrogen and the other is methyl; R3 is H or C1 to C4 alkyl; and n is an integer from 1 to 50.

17. The cationic electrodepositable coating composition according to claim 16, wherein R3 is a C1 to C3 alkyl group.

18. The cationic electrodepositable coating composition of claim 14, wherein the curing agent comprises a volatile group having a molecular weight of at least 70 g / mol, wherein the volatile group comprises a blocking agent and other organic byproducts generated and volatilized during the curing reaction of the electrodepositable coating composition, and wherein the volatile group is covalently bonded to the curing agent prior to curing.

19. The cationic electrodepositable coating composition according to claim 1 or 10, wherein the film-forming polymer containing cationic salt groups is present in the cationic electrodepositable coating composition in an amount of 40% to 90% by weight, based on the total weight of the resin solids of the cationic electrodepositable coating composition.

20. The cationic electrodepositable coating composition of claim 14, wherein the curing agent is present in the cationic electrodepositable coating composition in an amount of 10% to 60% by weight, based on the total weight of the resin solids of the cationic electrodepositable coating composition.

21. The cationic electrodepositable coating composition according to any one of claims 1, 2, 5-7 or 10, further comprising an aqueous medium comprising water and optionally one or more organic solvents.

22. The cationic electrodepositable coating composition of claim 21, wherein the aqueous medium comprises an organic solvent, the organic solvent comprising the following structure: R1 and R2 are each hydrogen, or one of R1 and R2 is hydrogen and the other is methyl; R3 is H or C1 to C4 alkyl; and n is an integer from 1 to 50.

23. The cationic electrodepositable coating composition according to claim 22, wherein R3 is a C1 to C3 alkyl group.

24. The cationic electrodepositable coating composition according to any one of claims 1, 2, 5-7 or 10, wherein the pH of the cationic electrodepositable coating composition is from 3.0 to 6.

5.

25. The cationic electrodepositable coating composition according to any one of claims 1, 2, 5-7 or 10, wherein the cationic electrodepositable coating composition comprises less than 0.1% by weight of tin and / or no more than 5% by weight of abrasive resin, based on the total solid weight of the resin in the electrodepositable coating composition.

26. The cationic electrodepositable coating composition according to any one of claims 1, 2, 5-7 or 10, wherein the cationic electrodepositable coating composition comprises less than 1% by weight of metallic pigment, based on the total weight of the pigment in the composition.

27. A cationic electrodepositable coating composition comprising: Cationic electrodepositable binders containing film-forming polymers with cationic salt groups; layered silicate pigments including kaolin clay; And a dispersible acid comprising a first acidic proton having a pKa of 1.1 to 4.6, wherein the cationic electrodepositable coating composition is formed by a method comprising the steps of: (1) heating an unneutralized film-forming polymer containing cationic salt-forming groups to a high temperature; (2) adding the dispersible acid to the unneutralized film-forming polymer containing cationic salt-forming groups under stirring to form a mixture; (3) adding the layered silicate pigment to the mixture under stirring at a high temperature; and (4) adding the film-forming polymer containing cationic salt-forming groups under stirring. The mixture of the layered silicate pigment and the dispersing acid is dispersed in an aqueous medium comprising water and a resin neutralizing acid, wherein the cationic salt-forming groups of the film-forming polymer containing cationic salt groups are at least partially neutralized by the resin neutralizing acid to form the film-forming polymer containing cationic salt groups; wherein the weight-to-molar ratio of the layered silicate pigment to the dispersing acid is 0.25 to 25 g / mmol, and wherein the pigment-to-binder (P:B) ratio of the layered silicate pigment to the cationic electrodepositable binder is 0.2:1 to 2.0:

1.

28. The cationic electrodepositable coating composition of claim 27, further comprising a curing agent.

29. The cationic electrodepositable coating composition according to claim 27 or 28, wherein the layered silicate pigment and the dispersive acid optionally form a layered silicate pigment-dispersive acid composite, and / or the layered silicate pigment, the dispersive acid, and the cationic film-forming polymer optionally form a layered silicate pigment-dispersive acid-film-forming polymer composite containing cationic salt groups.

30. A method for preparing an electrodeposable coating composition according to any one of claims 1 to 28, the method comprising the steps of: (1) Heating the unneutralized film-forming polymer containing cationic salt-forming groups to a high temperature; (2) Adding a dispersing acid to the unneutralized film-forming polymer containing cationic salt-forming groups under stirring to form a mixture; (3) Adding a layered silicate pigment, including kaolin clay, to the mixture; and (4) Dispersing the mixture of the film-forming polymer containing cationic salt-forming groups, the layered silicate pigment, and the dispersing acid under stirring in an aqueous medium comprising water and a resin neutralizing acid, wherein the cationic salt-forming groups in the film-forming polymer containing cationic salt-forming groups are neutralized by the resin neutralizing acid to form a film-forming polymer containing cationic salt-forming groups.

31. The method according to claim 30, wherein steps (1) to (4) are performed sequentially.

32. The method according to claim 30 or 31, wherein the method further comprises adding a curing agent during or after any step (1) to (4).

33. A method for coating a substrate, the method comprising electrodepositing a coating onto at least a portion of the substrate, the coating being derived from a cationic electrodepositable coating composition according to any one of claims 1 to 29.

34. The method of claim 33, further comprising subjecting the coating to curing conditions to form a coating that is at least partially cured on the substrate.

35. A coating formed by depositing the coating onto a substrate, said coating being derived from a cationic electrodepositable coating composition according to any one of claims 1 to 29, said coating comprising at least partially cured cationic electrodepositable binder and layered silicate pigment-dispersed acid complex.

36. A substrate having at least partially coated with a coating deposited by a cationic electrodepositable coating composition according to any one of claims 1 to 29.

37. The substrate of claim 36, wherein the substrate further comprises a pretreatment layer beneath the coating deposited by the cationic electrodeposable coating composition.

38. The substrate according to claim 36 or 37, wherein the substrate further comprises a topcoat layer on top of the coating deposited by the cationic electrodeposable coating composition.

39. The cationic electrodepositable coating composition according to any one of claims 1, 2, 5-7, 10, 27 or 28, wherein the pigment to binder (P:B) ratio of the layered silicate pigment to the cationic electrodepositable binder is at least 0.35:1.

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