Electrodepositable coating composition

Abstract

The present disclosure relates to an electrodepositable coating composition comprising: (a) a hydroxyl-functionalized branched polymerization product; (b) an ionic salt group-containing film-forming polymer different from the hydroxyl-functionalized branched polymerization product; and (c) a curing agent. A method of coating a substrate, a coating, and a coated substrate are also disclosed.

Description

Technical Field

[0001] The present disclosure relates to an electrodepositable coating composition, a treated substrate, and a method of coating a substrate. Background Art

[0002] As a coating application method, electrodeposition involves depositing a film-forming composition onto a conductive substrate under the influence of an applied potential. Compared to non-electrophoretic coating methods, electrodeposition is becoming increasingly popular in the coating industry because it provides higher coating utilization, excellent corrosion resistance, and low environmental pollution. Both cationic and anionic electrodeposition processes are used commercially. It is desirable to provide an electrodepositable coating composition that provides pit control and edge coverage. Summary of the invention

[0003] The present disclosure provides an electrodepositable coating composition comprising: (a) a hydroxyl-functionalized branched polymeric product; (b) a film-forming polymer containing ionic salt groups different from the hydroxyl-functionalized branched polymeric product; and (c) a curing agent.

[0004] The present disclosure also provides a method for coating a substrate, comprising: electrophoretically applying a coating deposited from an electrodepositable coating composition to at least a portion of the substrate, the electrodepositable coating composition comprising: (a) a hydroxyl-functionalized branched polymer product; (b) a film-forming polymer containing ionic salt groups different from the hydroxyl-functionalized branched polymer product; and (c) a curing agent.

[0005] The present disclosure further provides a coating deposited from an electrodepositable coating composition comprising: (a) a hydroxyl-functionalized branched polymeric product; (b) a film-forming polymer containing ionic salt groups different from the hydroxyl-functionalized branched polymeric product; and (c) a curing agent.

[0006] The present disclosure further provides a coated substrate having a coating comprising: (a) a hydroxyl-functionalized branched polymeric product; (b) a film-forming polymer containing ionic salt groups different from the hydroxyl-functionalized branched polymeric product; and (c) a curing agent. DETAILED DESCRIPTION

[0007] The present disclosure relates to an electrodepositable coating composition comprising: (a) a hydroxyl-functionalized branched polymeric product; (b) a film-forming polymer containing ionic salt groups different from the hydroxyl-functionalized branched polymeric product; and (c) a curing agent.

[0008] According to the present disclosure, the term "electrodepositable coating composition" refers to a composition capable of being deposited onto a conductive substrate under the influence of an electric potential applied between two electrodes immersed in the electrodepositable coating composition, one of which is the substrate to be coated.

[0009] Hydroxyl functionalized branched polymers

[0010] According to the present disclosure, an electrodepositable coating composition comprises a hydroxyl-functionalized branched polymeric product.

[0011] As used herein, the term "hydroxy-functional branched polymer product" refers to a polymer having a main carbon-based polymer backbone from which carbon-based side chains extend, and at least a portion of the carbon-based side chains include hydroxyl functional groups. The hydroxy-functional branched polymer product can be obtained by polymerizing at least one alpha-olefin monomer having at least six carbon atoms per molecule with at least one hydroxy-functional unsaturated monomer under conditions effective to promote branching. As used herein, the term "polymer product" refers to the product of the polymerization of monomers (i.e., polymer).

[0012] The hydroxy-functionalized branched polymeric product may comprise a branched polyalphaolefin.The branched polyalphaolefin may comprise constitutional units comprising residues of: (i) an alpha-olefin monomer having at least 6 carbon atoms; and (ii) a hydroxy-functional unsaturated monomer.

[0013] The alpha-olefin monomer may include an olefinic unsaturated organic compound having at least six carbon atoms and a terminal carbon-carbon bond. The olefinic unsaturated organic compound may have a structure H2C=CH-R, wherein R is a hydrocarbon group having at least four carbon atoms (such as at least six carbon atoms, such as at least 10 carbon atoms). The alpha-olefin monomer includes C6-C50 alpha-olefins, such as C6 to C40 alpha-olefins, such as C6 to C30 alpha-olefins, such as C6 to C20 alpha-olefins. R may be an alkyl group. As used herein, "alkyl" refers to a hydrocarbon chain that may be linear or branched and may include one or more hydrocarbon rings that are not aromatic. For example, the alpha-olefin monomer may include 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, or any combination thereof and other monomers.

[0014] Based on the total weight of the hydroxyl-functionalized branched polymer product, the hydroxyl-functionalized branched polymer product may include constituent units of alpha-olefin monomers in an amount of at least 3 weight %, such as at least 5 weight %, such as at least 20 weight %, such as at least 33 weight %, such as at least 40 weight %, such as at least 50 weight %, such as at least 65 weight %, such as at least 80 weight %, such as at least 88 weight %, such as at least 90 weight %. Based on the total weight of the hydroxyl-functionalized branched polymer product, the hydroxyl-functionalized branched polymer product may include constituent units of alpha-olefin monomers in an amount of no more than 97 weight %, such as no more than 95 weight %, such as no more than 88 weight %, such as no more than 80 weight %, such as no more than 67 weight %, such as no more than 60 weight %, such as no more than 50 weight %, such as no more than 35 weight %, such as no more than 20 weight %, such as no more than 12 weight %, such as no more than 10 weight %.Based on the total weight of the hydroxyl-functionalized branched polymer product, the hydroxyl-functionalized branched polymer product may contain constituent units of α-olefin monomers in an amount of 3 wt % to 97 wt %, such as 3 wt % to 95 wt %, such as 3 wt % to 88 wt %, such as 3 wt % to 80 wt %, such as 3 wt % to 67 wt %, such as 3 wt % to 60 wt %, such as 3 wt % to 50 wt %, such as 3 wt % to 35 wt %, such as 3 wt % to 20 wt %, such as 3 wt % to 12 wt %, such as 3 wt % to 10 wt %, such as 5 wt % to 97 wt %, such as 5 wt % to 95 wt %, such as 5 wt % to 88 wt %. %, such as 5 wt % to 80 wt %, such as 5 wt % to 67 wt %, such as 5 wt % to 60 wt %, such as 5 wt % to 50 wt %, such as 5 wt % to 35 wt %, such as 5 wt % to 20 wt %, such as 5 wt % to 12 wt %, such as 5 wt % to 10 wt %, such as 20 wt % to 97 wt %, such as 20 wt % to 95 wt %, such as 20 wt % to 88 wt %, such as 20 wt % to 80 wt %, such as 20 wt % to 67 wt %, such as 20 wt % to 60 wt %, such as 20 wt % to 50 wt %, such as 20 wt % to 35 wt %, 33 wt % to 9 7 wt %, such as 33 wt % to 95 wt %, such as 33 wt % to 88 wt %, such as 33 wt % to 80 wt %, such as 33 wt % to 67 wt %, such as 33 wt % to 60 wt %, such as 33 wt % to 50 wt %, such as 33 wt % to 35 wt %, such as 40 wt % to 97 wt %, such as 40 wt % to 95 wt %, such as 40 wt % to 88 wt %, such as 40 wt % to 80 wt %, such as 40 wt % to 67 wt %, such as 40 wt % to 60 wt %, such as 40 wt % to 50 wt %, such as 50 wt % to 97 wt %, such as 50 wt % to 95 wt %. %, such as 50 wt % to 88 wt %, such as 50 wt % to 80 wt %, such as 50 wt % to 67 wt %, such as 50 wt % to 60 wt %, such as 65 wt % to 97 wt %, such as 65 wt % to 95 wt %, such as 85 wt % to 88 wt %, such as 65 wt % to 80 wt %, such as 65 wt % to 67 wt %, such as 80 wt % to 97 wt %, such as 80 wt % to 95 wt %, such as 80 wt % to 88 wt %, such as 88 wt % to 97 wt %, such as 88 wt % to 95 wt %, such as 90 wt % to 97 wt %, such as 90 wt % to 95 wt %.

[0015] The hydroxyl-functional unsaturated monomer may include α,β-unsaturated alcohols. The hydroxyl-functional unsaturated monomer may include, for example, allyl alcohol, 5-hexene-1-ol, 3-hexene-1-ol, 4-pentene-1-ol, 3-pentene-1-ol, 3-butene-1-ol, crotyl alcohol, 9-trans-octadecene-1-ol, eicosene alcohol (9-cis-eicosene-1-ol), 9-decene-1-ol, 9-dodecene-1-ol, 10-undecenol, oleyl alcohol (9-cis-octadecene-1-ol), erucyl alcohol (13-cis-eicosene-1-ol), basil alcohol (13-trans-eicosene-1-ol), ethoxylated and / or propoxylated derivatives thereof, acetates and formates of these alcohols, or any combination thereof, and other monomers.

[0016] Based on the total weight of the hydroxyl-functional branched polymeric product, the hydroxyl-functional branched polymeric product may include constituent units of hydroxyl-functional unsaturated monomers in an amount of at least 3 wt%, such as at least 5 wt%, such as at least 20 wt%, such as at least 33 wt%, such as at least 40 wt%, such as at least 50 wt%, such as at least 65 wt%, such as at least 80 wt%, such as at least 88 wt%, such as at least 90 wt%. Based on the total weight of the hydroxyl-functional branched polymeric product, the hydroxyl-functional branched polymeric product may include constituent units of hydroxyl-functional unsaturated monomers in an amount of no more than 97 wt%, such as no more than 95 wt%, such as no more than 88 wt%, such as no more than 80 wt%, such as no more than 67 wt%, such as no more than 60 wt%, such as no more than 50 wt%, such as no more than 35 wt%, such as no more than 20 wt%, such as no more than 12 wt%, such as no more than 10 wt%.The hydroxyl-functional branched polymeric product may comprise constituent units of hydroxyl-functional unsaturated monomers in an amount of 3 wt % to 97 wt %, such as 3 wt % to 95 wt %, such as 3 wt % to 88 wt %, such as 3 wt % to 80 wt %, such as 3 wt % to 67 wt %, such as 3 wt % to 60 wt %, such as 3 wt % to 50 wt %, such as 3 wt % to 35 wt %, such as 3 wt % to 20 wt %, such as 3 wt % to 12 wt %, such as 3 wt % to 10 wt %, such as 5 wt % to 97 wt %, such as 5 wt % to 95 wt %, such as 5 wt % to 8 8 wt %, such as 5 wt % to 80 wt %, such as 5 wt % to 67 wt %, such as 5 wt % to 60 wt %, such as 5 wt % to 50 wt %, such as 5 wt % to 35 wt %, such as 5 wt % to 20 wt %, such as 5 wt % to 12 wt %, such as 5 wt % to 10 wt %, such as 20 wt % to 97 wt %, such as 20 wt % to 95 wt %, such as 20 wt % to 88 wt %, such as 20 wt % to 80 wt %, such as 20 wt % to 67 wt %, such as 20 wt % to 60 wt %, such as 20 wt % to 50 wt %, such as 20 wt % to 35 wt %, 33 wt % to 97 wt %, such as 33 wt % to 95 wt %, such as 33 wt % to 88 wt %, such as 33 wt % to 80 wt %, such as 33 wt % to 67 wt %, such as 33 wt % to 60 wt %, such as 33 wt % to 50 wt %, such as 33 wt % to 35 wt %, such as 40 wt % to 97 wt %, such as 40 wt % to 95 wt %, such as 40 wt % to 88 wt %, such as 40 wt % to 80 wt %, such as 40 wt % to 67 wt %, such as 40 wt % to 60 wt %, such as 40 wt % to 50 wt %, such as 50 wt % to 97 wt %, such as 50 wt % to 95 wt %. %, such as 50 wt % to 88 wt %, such as 50 wt % to 80 wt %, such as 50 wt % to 67 wt %, such as 50 wt % to 60 wt %, such as 65 wt % to 97 wt %, such as 65 wt % to 95 wt %, such as 85 wt % to 88 wt %, such as 65 wt % to 80 wt %, such as 65 wt % to 67 wt %, such as 80 wt % to 97 wt %, such as 80 wt % to 95 wt %, such as 80 wt % to 88 wt %, such as 88 wt % to 97 wt %, such as 88 wt % to 95 wt %, such as 90 wt % to 97 wt %, such as 90 wt % to 95 wt %.

[0017] The molar ratio of the α-olefin monomer to the hydroxyl functional unsaturated monomer may be from 20:1 to 1:20, or from 10:1 to 1:10, or from 8:1 to 1:2.

[0018] The polymer product can be obtained, for example, by subjecting a mixture of an alpha-olefin monomer, a hydroxyl-functional unsaturated monomer, and at least one polymerization initiator to reaction conditions sufficient to copolymerize the alpha-olefin monomer and the hydroxyl-functional unsaturated monomer. The reaction conditions are not limited as long as the monomers can react to form a polymer product, and a non-limiting exemplary process is described below.

[0019] The polymerized product can be prepared by polymerizing an ethylenically unsaturated polymerizable monomer composition in a dispersion medium comprising water by techniques well known in the art. For example, the monomer composition can be dissolved or dispersed in water and subjected to addition polymerization conditions by heating in the presence of a free radical initiator. The monomer composition can optionally include a surfactant to assist in dispersing the monomer composition, and the surfactant can be a reactive surfactant or a non-reactive surfactant. Alternatively, the monomer composition can be substantially free of, essentially free of, or completely free of reactive and / or non-reactive surfactants. The time and temperature of the polymerization will depend on each other, the selected ingredients, and in some cases the scale of the reaction. The polymerization can be carried out for 2 to 20 hours at, for example, 40° C. to 100° C.

[0020] The free radical initiator used for the polymerization can be selected from any free radical initiator used in aqueous latex polymerization techniques, including redox couple initiators, organic peroxides, peroxides, hydroperoxides, peroxydicarbonates, azo compounds, and the like.

[0021] Alternatively, the polymer product can be prepared in an organic solution by techniques well known in the art. For example, the polymer product can be prepared by conventional free radical initiated solution polymerization techniques, wherein the ethylenically unsaturated monomer composition is dissolved in a solvent or a solvent mixture and polymerized in the presence of a free radical initiator to form a polymer product, the polymer product comprising a constituent unit, the constituent unit comprising the residue of an unsaturated monomer. Examples of suitable solvents that can be used for organic solution polymerization include alcohols, such as ethanol, tert-butyl alcohol and tert-amyl alcohol, tert-butyl alcohol and tert-amyl alcohol; ketones, such as acetone, methyl ethyl ketone; and ethers, such as dimethyl ether of ethylene glycol. Examples of suitable free radical initiators include free radical initiators soluble in a mixture of monomers, such as azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), azobis-(α, γ-dimethylvaleronitrile), tert-butyl perbenzoate, tert-butyl peracetate, benzoyl peroxide and di-tert-butyl peroxide. Based on the gross weight of polymerized product or monomer composition, free radical initiator can exist with the amount of 0.01 wt % to 6 wt % (such as 1.0 wt % to 4.0 wt %, such as 2.0 wt % to 3.5 wt %).In an example, solvent can be first heated to reflux, and the mixture of ethylenically unsaturated monomer composition and free radical initiator is slowly added to the reflux solvent.By the gross weight of ethylenically unsaturated monomer composition, reaction mixture can be maintained at polymerization temperature to reduce free monomer content to less than 1.0 wt %, such as less than 0.5 wt %.The time and temperature of polymerization can depend on each other, selected composition and the scale of reaction in some cases.For example, polymerization can be carried out at 40 ℃ to 100 ℃ for 2 hours to 20 hours.

[0022] The hydroxyl functionalized branched polymeric product may have a hydroxyl equivalent weight of at least 50 g / eq (such as at least 75 g / eq, such as at least 100 g / eq, such as at least 125 g / eq, such as at least 140 g / eq). The hydroxyl functionalized branched polymeric product may have a hydroxyl equivalent weight of no more than 3,000 g / mol (such as no more than 1,500 g / mol, such as no more than 750 g / mol, such as no more than 500 g / mol, such as no more than 250 g / mol, such as no more than 150 g / mol). The hydroxyl-functional branched polymer product may have a molecular weight of 50 to 3,000 g / eq (such as 50 to 1,500 g / eq, such as 50 to 750 g / eq, such as 50 to 500 g / eq, such as 50 to 250 g / eq, such as 50 to 150 g / eq, such as 75 to 3,000 g / eq, such as 75 to 1,500 g / eq, such as 75 to 750 g / eq, such as 75 to 500 g / eq, such as 75 to 250 g / eq, such as 75 to 150 g / eq, such as 100 to 3,000 g / eq, such as 100 to 1,500 g / eq, such as 100 to 750 g / eq, Such as 100 to 500 g / eq, such as 100 to 250 g / eq, such as 100 to 150 g / eq, such as 125 to 3,000 g / eq, such as 125 to 1,500 g / eq, such as 125 to 750 g / eq, such as 125 to 500 g / eq, such as 125 to 250 g / eq, such as 125 to 150 g / eq, such as 140 to 3,000 g / eq, such as 140 to 1,500 g / eq, such as 140 to 750 g / eq, such as 140 to 500 g / eq, such as 140 to 250 g / eq, such as 140 to 150 g / eq). As used herein, for a hydroxy-functional branched polymeric product, "hydroxy equivalent weight" is a theoretical number determined by dividing the molecular weight of the hydroxy-functional branched polymeric product by the number of hydroxyl groups present in the hydroxy-functional branched polymeric product.

[0023] The hydroxyl functionalized branched polymer product may have a number average molecular weight of at least 500 g / mol, such as at least 1,000 g / mol, such as at least 1,500 g / mol, such as at least 1,800 g / mol. The hydroxyl functionalized branched polymer product may have a number average molecular weight of no more than 10,000 g / mol, such as no more than 5,000 g / mol, such as no more than 3,000 g / mol, such as no more than 2,200 g / mol. The hydroxyl functionalized branched polymer product may have a molecular weight of 500 to 10,000 g / mol (such as 500 to 5,000 g / mol, such as 500 to 3,000 g / mol, such as 500 to 2,200 g / mol, such as 1,000 to 10,000 g / mol, such as 1,000 to 5,000 g / mol, such as 1,000 to 3,000 g / mol, such as 1,000 to 2,200 g / mol, such as 1,500 to 10,000 g / mol 0 g / mol, such as 1,500 to 5,000 g / mol, such as 1,500 to 3,000 g / mol, such as 1,500 to 2,200 g / mol, such as 1,800 to 10,000 g / mol, such as 1,800 to 5,000 g / mol, such as 1,800 to 3,000 g / mol, such as 1,800 to 2,200 g / mol) as determined by gel permeation chromatography using polystyrene calibration standards.

[0024] As used herein, unless otherwise indicated, the term "number average molecular weight (M)" n )" means the number average molecular weight (M) as determined by gel permeation chromatography using the following n ): A Waters 2695 separation module with a Waters 410 differential refractometer (RI detector), polystyrene standards with molecular weights ranging from approximately 500 g / mol to 900,000 g / mol, dimethylformamide (DMF) with 0.05 M lithium bromide (LiBr) as eluent at a flow rate of 0.5 mL / min, and an Asahipak GF-510HQ column were used for separation.

[0025] The hydroxyl functional branched polymer product may have a z-average molecular weight of at least 4,000 g / mol, such as at least 6,000 g / mol, such as at least 8,500 g / mol. The hydroxyl functional branched polymer product may have a z-average molecular weight of no more than 15,000 g / mol, such as no more than 12,000 g / mol, such as no more than 9,000 g / mol. The hydroxyl-functional branched polymeric product may have a z-average molecular weight of 4,000 to 15,000 g / mol, such as 4,000 to 12,000 g / mol, such as 4,000 to 9,000 g / mol, such as 6,000 to 15,000 g / mol, such as 6,000 to 12,000 g / mol, such as 6,000 to 9,000 g / mol, such as 8,500 to 15,000 g / mol, such as 8,500 to 12,000 g / mol, such as 8,500 to 9,000 g / mol, as determined by gel permeation chromatography using polystyrene calibration standards.

[0026] As used herein, unless otherwise indicated, the term "z-average molecular weight (M z )" means the z-average molecular weight (M) as determined by gel permeation chromatography using the following z ): A Waters 2695 separation module with a Waters 410 differential refractometer (RI detector), polystyrene standards with molecular weights ranging from approximately 500 g / mol to 900,000 g / mol, dimethylformamide (DMF) with 0.05 M lithium bromide (LiBr) as eluent at a flow rate of 0.5 mL / min, and an Asahipak GF-510HQ column for separation.

[0027] The hydroxyl-functional branched polymeric product can exist as the reaction product of the hydroxyl-functional branched polymeric product and a polyisocyanate. For example, the hydroxyl-functional branched polymeric product can be chain extended by reaction with a polyisocyanate, wherein the hydroxyl functional groups from the hydroxyl-functional branched polymeric product are in molar excess relative to the isocyanato functional groups of the polyisocyanate.

[0028] Based on the total weight of the reaction product, the polyisocyanate may constitute at least 2 wt % (such as at least 5 wt %, such as at least 10 wt %) of the reaction product, and the balance may comprise the hydroxyl-functional branched polymer product, for example, at least 80 wt %, such as at least 90 wt %, such as at least 95 wt %, such as at least 98 wt %).

[0029] The ratio of hydroxyl functional groups from the hydroxyl-functional branched polymeric product to isocyanato groups from the polyisocyanate may be at least 2.45:1, such as at least 4.9:1.

[0030] The hydroxy-functional branched polymer product may be present as a blocking agent for the polyisocyanate curing agent.

[0031] Based on the total weight of the resin solids of the electrodepositable coating composition, the above-mentioned hydroxyl-functionalized branched polymeric product can be present in the electrodepositable coating composition in an amount of at least 0.01 wt % (such as at least 0.1 wt %, such as at least 0.2 wt %, such as at least 0.4 wt %, such as at least 0.5 wt %, such as at least 1 wt %). Based on the total weight of the resin solids of the electrodepositable coating composition, the hydroxyl-functionalized branched polymeric product can be present in the electrodepositable coating composition in an amount of no more than 10 wt % (such as no more than 3 wt %, such as no more than 2 wt %, such as no more than 1 wt %, such as no more than 0.85 wt %). The hydroxyl-functional branched polymeric product may be present in an amount of 0.01 wt % to 10 wt % (such as 0.1 wt % to 10 wt %, such as 0.2 wt % to 10 wt %, such as 0.4 wt % to 10 wt %, such as 0.5 wt % to 10 wt %, such as 1 wt % to 10 wt %, such as 0.05 wt % to 3 wt %, such as 0.1 wt % to 3 wt %, such as 0.2 wt % to 3 wt %, such as 0.4 wt % to 3 wt %, such as 0.5 wt % to 3 wt %, such as 1 wt % to 3 wt %, such as 0.01 wt % to 2 wt %, such as 0.1 wt % to 2 wt %, such as 0.2 wt % to 2 wt %, such as 0.4 wt % to 2 wt %, such as 0.5 wt % to 2 wt %, such as 1 wt % to 2 wt %, 0.01 wt % to 1 wt %, such as 0.1 wt % to 1 wt %, such as 0.2 wt % to 1 wt %, such as 0.4 wt % to 1 wt %, such as 0.5 wt % to 1 wt %, 0.01 wt % to 0.85 wt %, such as 0.1 wt % to 0.85 wt %, such as 0.2 wt % to 0.85 wt %, such as 0.4 wt % to 0.85 wt %, such as 0.5 wt % to 0.85 wt %) is present in the electrodepositable coating composition.

[0032] It has surprisingly been found that the use of a hydroxy-functional branched polymeric product in an electrodepositable coating composition in the amounts taught herein results in a deposited coating having improved pitting resistance.

[0033] Compared to a substrate coated with a comparative electrodepositable coating composition that does not include a hydroxyl-functionalized branched polymeric product but otherwise has the same composition as an electrodepositable coating composition, the hydroxyl-functionalized branched polymeric product is present in the electrodepositable coating composition in an amount disclosed herein that can result in a reduction in the depth of the pits formed in the cured coating during the curing of the electrodepositable coating composition. For example, compared to a comparative electrodepositable coating composition having the same composition as an electrodepositable coating composition except that it does not include an addition polymer, the pit depth of the coating on the substrate can be reduced by at least 10%, such as at least 20%, such as at least 30%, such as at least 40%, such as at least 50%, such as at least 55%, such as at least 60%, as measured by a pit resistance test method. The pit depth of the coating on the substrate can be 15 microns or less, such as 12 microns or less, such as 10 microns or less, such as 9 microns or less, such as 8 microns or less, as measured by a pit depth test method. The pit depth test method is defined in the following embodiment section.

[0034] Film-forming polymers containing ionic salt groups

[0035] According to the present disclosure, the electrodepositable coating composition may further include a film-forming polymer containing an ionic salt group. The film-forming polymer containing an ionic salt group is different from the above-mentioned hydroxyl-functionalized branched polymer product.

[0036] According to the present disclosure, the film-forming polymer containing ionic salt groups may include film-forming polymers containing cationic salt groups. Film-forming polymers containing cationic salt groups can be used in coating compositions that can be electrodeposited by cations. As used herein, the term "film-forming polymer containing cationic salt groups" refers to polymers containing cationic groups that are at least partially neutralized, such as sulfonium groups and ammonium groups that impart positive charge. As used herein, the term "polymer" encompasses but is not limited to oligomers and both homopolymers and copolymers. Film-forming polymers containing cationic salt groups may include active hydrogen functional groups. As used herein, the term "active hydrogen functional group" refers to those groups that react with isocyanate as determined by the Zerevitenov test as discussed above, and includes, for example, hydroxyl, primary amino or secondary amino and thiol groups. Film-forming polymers containing cationic salt groups including active hydrogen functional groups may be referred to as film-forming polymers containing active hydrogen, containing cationic salt groups.

[0037] Examples of polymers suitable for use as the cationic salt group-containing film-forming polymer in the present disclosure include, but are not limited to, alkyd polymers, acrylics, polyepoxides, polyamides, polyurethanes, polyureas, polyethers, polyesters, and the like.

[0038] More specific examples of suitable active hydrogen-containing, cationic salt group-containing film-forming polymers include polyepoxide-amine adducts, such as adducts of polyglycidyl ethers of polyphenols (such as bisphenol A) with primary and / or secondary amines, as described in U.S. Pat. No. 4,031,050 at column 3, line 27 to column 5, line 50, U.S. Pat. No. 4,452,963 at column 5, line 58 to column 6, line 66, and U.S. Pat. No. 6,017,432 at column 2, line 66 to column 6, line 26, portions of which are incorporated herein by reference. A portion of the amine reacted with the polyepoxide may be a ketimine of a polyamine, such as described in U.S. Pat. No. 4,104,147 at column 6, line 23 to column 7, line 23, portions of which are incorporated herein by reference. Ungelled polyepoxide-polyoxyalkylene polyamine resins are also suitable, such as those described in U.S. Pat. No. 4,432,850 at column 2, line 60 to column 5, line 58, the cited portions of which are incorporated herein by reference. In addition, cationic acrylic resins such as those described in U.S. Pat. No. 3,455,806 at column 2, line 18 to column 3, line 61 and U.S. Pat. No. 3,928,157 at column 2, line 29 to column 3, line 21, both of which are incorporated herein by reference, may be used.

[0039] 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 the present disclosure. Examples of these resins are those formed by reacting organic polyepoxides with tertiary amine acid salts. Such resins are described in U.S. Pat. No. 3,962,165, Column 2, Line 3 to Column 11, Line 7; No. 3,975,346, Column 1, Line 62 to Column 17, Line 25, and U.S. Pat. No. 4,001,156, Column 1, Line 37 to Column 16, Line 7, and these portions of the U.S. Pat. No. are incorporated herein by reference. Examples of other suitable cationic resins include resins containing ternary sulfonium salt groups, such as those described in U.S. Pat. No. 3,793,278, Column 1, Line 32 to Column 5, Line 20, and this portion of the U.S. Pat. No. is incorporated herein by reference. Furthermore, it is also possible to employ cationic resins that cure by a transesterification mechanism, as described in European Patent Application No. 12463 B1, page 2, line 1 to page 6, line 25, this part of which is incorporated herein by reference.

[0040] Other suitable film-forming polymers containing cationic salt groups include those film-forming polymers that can form an electrodepositable coating composition that resists photodegradation. Such polymers include polymers containing cationic amine salt groups, which are derived from side groups and / or terminal amino groups disclosed in paragraphs

[0064] to

[0088] of U.S. Patent Application Publication No. 2003 / 0054193A1, which are incorporated herein by reference in this section. Also suitable are resins containing active hydrogen and cationic salt groups derived from polyglycidyl ethers of polyphenols that are substantially free of aliphatic carbon atoms bonded to more than one aromatic group, which are disclosed in side groups and / or terminal amino groups disclosed in paragraphs

[0096] to

[0123] of U.S. Patent Application Publication No. 2003 / 0054193A1, which are incorporated herein by reference in this section.

[0041] The active hydrogen-containing, cationic salt-containing film-forming polymer is made cationic and water-dispersible by at least partially neutralizing with an acid. Suitable acids include organic acids and inorganic acids. Non-limiting examples of suitable organic acids include formic acid, acetic acid, methanesulfonic acid, and lactic acid. Non-limiting examples of suitable inorganic acids include phosphoric acid and aminosulfonic acid. "Aminosulfonic acid" means aminosulfonic acid itself or a derivative thereof, such as aminosulfonic acid or a derivative thereof having the formula:

[0042]

[0043] wherein R is hydrogen or an alkyl group having 1 to 4 carbon atoms. Mixtures of the above mentioned acids may also be used in the present disclosure.

[0044] The degree of neutralization of the film-forming polymer containing cationic salt groups can vary with the specific polymer involved. However, sufficient acid should be used to fully neutralize the film-forming polymer containing cationic salt groups so that the film-forming polymer containing cationic salt groups can be dispersed in the aqueous dispersion medium. For example, the amount of acid used can provide at least 20% of the total theoretical neutralization. It is also possible to use an excess of acid exceeding 100% of the total theoretical neutralization required amount. For example, based on the total amine in the film-forming polymer containing active hydrogen and cationic salt groups, the amount of acid used to neutralize the film-forming polymer containing cationic salt groups can be ≧0.1%. Alternatively, based on the total amine in the film-forming polymer containing active hydrogen and cationic salt groups, the amount of acid used to neutralize the film-forming polymer containing active hydrogen and cationic salt groups can be ≦100%. The range of the total amount of acid used to neutralize the film-forming polymer containing cationic salt groups can be between any combination of the values ​​stated in the preceding sentence (including the stated values). For example, the total amount of acid used to neutralize the active hydrogen-containing, cationic salt group-containing film-forming polymer may be 20%, 35%, 50%, 60% or 80% based on the total amines in the cationic salt group-containing film-forming polymer.

[0045] According to the present disclosure, based on the total weight of the resin solids of the electrodepositable coating composition, the film-forming polymer containing cationic salt groups can 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), and can be present in an amount of no more than 89.99% by weight (such as no more than 80% by weight, such as no more than 75% by weight). Based on the total weight of the resin solids of the electrodepositable coating composition, the film-forming polymer containing cationic salt groups can be present in the cationic electrodepositable coating composition in an amount of 40% to 89.99% by weight (such as 50% to 80% by weight, such as 60% to 75% by weight). As used herein, "resin solids" include film-forming polymers containing ionic salt groups, curing agents, hydroxyl-functionalized branched polymer products, and any additional water-dispersible uncolored components present in the electrodepositable coating composition.

[0046] According to the present disclosure, the film-forming polymer containing ionic salt groups can include film-forming polymers containing anionic salt groups. As used herein, the term "film-forming polymer containing anionic salt groups" refers to anionic polymers containing anionic functional groups at least partially neutralized such as carboxylic acid groups and phosphoric acid groups that impart negative charge. As used herein, the term "polymer" encompasses but is not limited to both oligomers and homopolymers and copolymers. The film-forming polymer containing anionic salt groups can include active hydrogen functional groups. As used herein, the term "active hydrogen functional group" refers to those groups that react with isocyanate as determined by the Zerevitenov test as discussed above, and includes, for example, hydroxyl, primary amino or secondary amino and thiol groups. The film-forming polymer containing anionic salt groups including active hydrogen functional groups can be referred to as film-forming polymers containing active hydrogen, containing anionic salt groups. The film-forming polymer containing anionic salt groups can be used in anion electrodepositable coating compositions.

[0047] The film-forming polymer containing anionic salt groups may include alkali-soluble, carboxylic acid group-containing film-forming polymers, such as reaction products or adducts of drying oils or semi-drying fatty acid esters with dicarboxylic acids or anhydrides; and reaction products of fatty acid esters, unsaturated acids or anhydrides with any additional unsaturated modifying materials (which are further reacted with polyols). Also suitable are at least partially neutralized interpolymers of hydroxyalkyl esters of unsaturated carboxylic acids, unsaturated carboxylic acids and at least one other ethylenically unsaturated monomer. Still another suitable anionic electrodepositable resin comprises an alkyd resin-aminoplast vehicle, i.e., a vehicle containing an alkyd resin and an amine-aldehyde resin. Another suitable anionic electrodepositable resin composition includes mixed esters of resin polyols. Other acid-functional polymers may also be used, such as phosphorylated polyepoxides or phosphorylated acrylic polymers. Exemplary phosphorylated polyepoxides are disclosed in U.S. Patent Application Publication Nos. 2009-0045071

[0004] -

[0015] and U.S. Patent Application No. 13 / 232,093

[0014] -

[0040] , the cited portions of which are incorporated herein by reference. Also suitable are resins comprising one or more pendant carbamate functional groups, such as those described in U.S. Patent No. 6,165,338 at column 2, line 66 to column 7, line 26, the cited portions of which are incorporated herein by reference.

[0048] According to the present disclosure, based on the total weight of the resin solids of the electrodepositable coating composition, the film-forming polymer containing anionic salt groups can be present in the anionic electrodepositable coating composition in an amount of at least 50 wt % (such as at least 55 wt %, such as at least 60 wt %), and can be present in an amount of no more than 90 wt % (such as no more than 80 wt %, such as no more than 75 wt %). Based on the total weight of the resin solids of the electrodepositable coating composition, the film-forming polymer containing anionic salt groups can be present in an anionic electrodepositable coating composition in an amount of 50% to 90%, such as 55% to 80%, such as 60% to 75%.

[0049] Curing agent

[0050] According to the present disclosure, the coating composition of the present disclosure that can be deposited can further include a curing agent. The curing agent can be reactive with a hydroxyl-functionalized branched polymer product and a film-forming polymer containing an ionic salt group. The curing agent can react with the reactive groups (such as active hydrogen groups) of the film-forming polymer containing an ionic salt group and the hydroxyl-functionalized branched polymer product to achieve the curing of the coating composition to form a coating. As used herein, the term "curing", "cured" or similar terms used in conjunction with the coating composition that can be deposited as described herein means that at least a portion of the components of the coating composition that can be deposited are crosslinked to form a coating. In addition, the curing of the coating composition that can be deposited refers to subjecting the composition to curing conditions (e.g., elevated temperature), thereby causing the reactive functional groups of the components of the coating composition that can be deposited to react, and causing 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, including allyl ether derivatives thereof.

[0051] Suitable at least partially blocked polyisocyanates include aliphatic polyisocyanates, aromatic polyisocyanates and mixtures thereof. The curing agent may include at least partially blocked aliphatic polyisocyanates. Suitable at least partially blocked aliphatic polyisocyanates include, for example, fully blocked aliphatic polyisocyanates, such as those described in U.S. Pat. No. 3,984,299, Column 1, Line 57 to Column 3, Line 15, which are incorporated herein by reference, or partially blocked aliphatic polyisocyanates that react with the polymer backbone, such as described in U.S. Pat. No. 3,947,338, Column 2, Line 65 to Column 4, Line 30, which are also incorporated herein by reference. "Blocked" means that the isocyanate group has reacted with a compound so that the resulting blocked isocyanate group is stable to active hydrogen at ambient temperature, but reacts with active hydrogen in the film-forming polymer at elevated temperatures (such as between 90° C. and 200° C.). The polyisocyanate curing agent may be a fully blocked polyisocyanate having substantially no free isocyanate groups.

[0052] The polyisocyanate curing agent may include diisocyanates, higher functional polyisocyanates, or combinations thereof. For example, the polyisocyanate curing agent may include aliphatic polyisocyanates and / or aromatic polyisocyanates. The aliphatic polyisocyanate may include (i) alkylene isocyanates such as trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate ("HDI"), 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene 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"), cyclotrimer of 1,6-hexamethylene diisocyanate (also known as isocyanurate trimer of HDI, available as Desmodur N3300 from Convestro AG commercially available) and m-tetramethylxylylene diisocyanate (can be Commercially available from Allnex SA). The aromatic polyisocyanate may comprise (i) an arylene isocyanate such as m-phenylene diisocyanate, p-phenylene diisocyanate, 1,5-naphthalene diisocyanate and 1,4-naphthalene diisocyanate, and (ii) an aralkylene isocyanate such as 4,4'-diphenylmethane ("MDI"), 2,4-tolylene diisocyanate or 2,6-tolylene diisocyanate ("TDI") or mixtures thereof, 4,4-toluidine diisocyanate and xylylene diisocyanate. Triisocyanates such as triphenylmethane-4,4',4"-triisocyanate, 1,3,5-triisocyanatobenzene and 2,4,6-triisocyanatotoluene; tetraisocyanates such as 4,4'-diphenyldimethylmethane-2,2',5,5'-tetraisocyanate; and polymeric polyisocyanates such as tolylene diisocyanate dimer and trimer, etc. can also be used. The curing agent can include a blocked polyisocyanate selected from polymeric polyisocyanates such as polymeric HDI, polymeric MDI, polymeric isophorone diisocyanate, etc. The curing agent can also include a blocked trimer of hexamethylene diisocyanate, which can be Desmodur Commercially available from Covestro AG. Mixtures of polyisocyanate curing agents may also be used.

[0053] The polyisocyanate curing agent may be at least partially blocked with at least one blocking agent selected from the following items: 1,2-alkanediol, for example, 1,2-propylene glycol; 1,3-alkanediol, for example, 1,3-butanediol; benzyl alcohol, for example, benzyl alcohol; allyl alcohol, for example, allyl alcohol; caprolactam; dialkylamine, for example, dibutylamine; and mixtures thereof. The polyisocyanate curing agent may be at least partially blocked with at least one 1,2-alkanediol having three or more carbon atoms (for example, 1,2-butanediol).

[0054] Other suitable end-capping agents include aliphatic, alicyclic or aromatic alkyl monoalcohols or phenolic compounds, including, for example, lower aliphatic alcohols, such as methanol, ethanol and n-butanol; alicyclic alcohols, such as cyclohexanol; aromatic alkyl alcohols, such as phenylcarbinol and methylphenylcarbinol; and phenolic compounds, such as phenol itself and substituted phenols, wherein the substituents do not affect the coating operation, such as cresol and nitrophenol. Ethylene glycol ethers and glycol amines can also be used as end-capping agents. Suitable glycol ethers include ethylene glycol butyl ether, diethylene glycol butyl ether, ethylene glycol methyl ether and propylene glycol methyl ether. Other suitable end-capping agents include oximes, such as methyl ethyl ketone oxime, acetone oxime and cyclohexanone oxime.

[0055] Curing agents may include aminoplast resins. Aminoplast resins are condensation products of aldehydes with materials carrying amino or amide groups. Condensation products obtained from the reaction of alcohols and aldehydes with melamine, urea or benzoguanamine may be used. However, condensation products of other amines and amides may also be used, for example, aldehyde condensates of alkyl and aryl substituted derivatives of triazines, diazines, triazoles, guanidines, guanamines and such compounds as alkyl-substituted and aryl-substituted ureas and alkyl-substituted 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, 3,4,6-tris(ethylamino)-1,3,5-triazine, etc. Suitable aldehydes include formaldehyde, acetaldehyde, crotonaldehyde, acrolein, benzaldehyde, furfural, glyoxal, etc.

[0056] The aminoplast resin may contain methylol 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 an organic solvent. For this purpose, any monohydric alcohol may be employed, including such alcohols as methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, and others, as well as benzyl alcohol and other aromatic alcohols, cyclic alcohols such as cyclohexanol, monoethers of ethylene glycol such as Cello solves and Carbitols, and halogen-substituted or other substituted alcohols such as 3-chloropropanol and butoxyethanol.

[0057] A non-limiting example of a commercially available aminoplast resin is the aminoplast resin sold under the trademark ANTI-TREAT® from Allnex Belgium SA / NV. (such as CYMEL 1130 and 1156) and products from INEOS Melamines under the trademark (such as RESIMENE 750 and 753) are commercially available aminoplast resins. Examples of suitable aminoplast resins also include those described in U.S. Pat. No. 3,937,679 at column 16, line 3 to column 17, line 47, which portion of the U.S. Pat. No. is hereby incorporated by reference. As disclosed in the foregoing portion of the '679 patent, aminoplasts can be used in combination with methylol phenol ethers.

[0058] Phenolic plastic resin is formed by condensation of aldehyde and phenol. 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, cresols or substituted phenols, in which hydrocarbon groups with straight, branched or cyclic structures replace hydrogen in the aromatic ring. Mixtures of these phenols can also be used. Some specific examples of suitable phenols are p-phenylphenol, p-tert-butylphenol, p-tert-amylphenol, cyclopentylphenol and phenols substituted with unsaturated hydrocarbons, such as monobutenylphenol containing butenyl in the ortho, meta or para position, and wherein double bonds appear in various positions of the hydrocarbon chain.

[0059] As described above, aminoplast resins and phenoplast resins are further described in US Pat. No. 4,812,215 at column 6, line 20 to column 7, line 12, the cited portions of which are incorporated herein by reference.

[0060] According to the total weight of the resin solids of the electrodepositable coating composition, the curing agent can be present in the cationic electrodepositable coating composition in an amount of at least 10 wt %, such as at least 20 wt %, such as at least 25 wt %, and can be present in an amount of no more than 60 wt %, such as no more than 59.95 wt %, such as no more than 50 wt %, such as no more than 40 wt %. According to the total weight of the resin solids of the electrodepositable coating composition, the curing agent can be present in the cationic electrodepositable coating composition in an amount of 10 wt % to 60 wt %, such as 10 wt % to 59.95 wt %, such as 20 wt % to 50 wt %, such as 25 wt % to 40 wt %.

[0061] Based on the total weight of the resin solids of the electrodepositable coating composition, the curing agent may be present in the anionic electrodepositable coating composition in an amount of at least 10 wt % (such as at least 20 wt %, such as at least 25 wt %), and may be present in an amount of no more than 50 wt % (such as no more than 45 wt %, such as no more than 40 wt %). Based on the total weight of the resin solids of the electrodepositable coating composition, the curing agent may be present in an anionic electrodepositable coating composition in an amount of 10 wt % to 50 wt % (such as 20 wt % to 45 wt %, such as 25 wt % to 40 wt %).

[0062] Other components of the electrodepositable coating composition

[0063] In addition to the hydroxy-functional branched polymeric product, the film-forming polymer containing ionic salt groups, and the curing agent described above, the electrodepositable coating composition according to the present disclosure may optionally comprise one or more additional components.

[0064] According to the present disclosure, the coating composition that can be electrodeposited can optionally include a catalyst for catalyzing the reaction between the curing agent and the polymer. Examples of catalysts suitable for cationic electrodeposited coating compositions include, but are not limited to, organotin compounds (e.g., dibutyltin oxide and dioctyltin oxide) and salts thereof (e.g., dibutyltin diacetate); other metal oxides (e.g., oxides of cerium, zirconium and bismuth) and salts thereof (e.g., bismuth sulfamate and bismuth lactate); or cyclic guanidines, such as the cyclic guanidines described in U.S. Pat. No. 7,842,762, Column 1, Line 53 to Column 4, Line 18 and Column 16, Line 62 to Column 19, Line 8, the cited portion of which is incorporated herein by reference. Examples of catalysts suitable for anionic electrodeposited coating compositions include latent acid catalysts, specific examples of which are identified in WO 2007 / 118024 (the cited portion of which is incorporated herein by reference) in paragraph

[0031] and include, but are not limited to, ammonium hexafluoroantimonate, quaternary salts of SbF6 (e.g., XC-7231), tertiary amine salts of SbF6 (e.g., XC-9223), Zn salts of trifluoromethanesulfonic acid (e.g., A202 and A218), quaternary salts of trifluoromethanesulfonic acid (e.g., XC-A230) and diethylamine salt of trifluoromethanesulfonic acid (e.g., A233) (all commercially available from King Industries) and / or mixtures thereof. Latent acid catalysts can be formed by preparing derivatives of acid catalysts such as p-toluenesulfonic acid (pTSA) or other sulfonic acids. For example, a well-known group of blocked acid catalysts are amine salts of aromatic sulfonic acids, such as pyridinium p-toluenesulfonate. Such sulfonates are not as active as the free acids in promoting crosslinking. During curing, the catalyst can be activated by heating.

[0065] According to the present disclosure, the electrodepositable coating composition of the present disclosure may optionally include a pit control additive that can be incorporated into the coating composition, such as, for example, a polyalkylene oxide polymer that can include a copolymer of butylene oxide and propylene oxide. According to the present disclosure, the molar ratio of butylene oxide to propylene oxide in the monomer mixture used to prepare the polyalkylene oxide polymer and in the resulting polyalkylene oxide polymer may be at least 1:1, such as at least 3:1, such as at least 5:1, and in some cases, may be no more than 50:1, such as no more than 30:1, such as no more than 20:1. According to the present disclosure, the molar ratio of butylene oxide to propylene oxide in the monomer mixture used to prepare the polyalkylene oxide polymer and in the resulting polyalkylene oxide polymer may be 1:1 to 50:1, such as 3:1 to 30:1, such as 5:1 to 20:1.

[0066] The polyalkylene oxide polymer may contain at least two hydroxyl functional groups, and may be difunctional, trifunctional, or tetrafunctional. As used herein, "hydroxyl functional group" includes -OH groups. For clarity, the polyalkylene oxide polymer may include additional functional groups in addition to hydroxyl functional groups. As used herein, "monofunctional", when used with respect to the number of hydroxyl functional groups included in a specific monomer or polymer, means a monomer or polymer that includes one (1) hydroxyl functional group per molecule. As used herein, "difunctional", when used with respect to the number of hydroxyl functional groups included in a specific monomer or polymer, means a monomer or polymer that includes two (2) hydroxyl functional groups per molecule. As used herein, "trifunctional", when used with respect to the number of hydroxyl functional groups included in a specific monomer or polymer, means a monomer or polymer that includes three (3) hydroxyl functional groups per molecule. As used herein, "tetrafunctional," when used with respect to the number of hydroxyl functional groups included by a particular monomer or polymer, means a monomer or polymer that includes four (4) hydroxyl functional groups per molecule.

[0067] The hydroxyl equivalent weight of the polyalkylene oxide polymer may be at least 100 g / mol, such as at least 200 g / mol, such as at least 400 g / mol, and may be no more than 2,000 g / mol, such as no more than 1,000 g / mol, such as no more than 800 g / mol. The hydroxyl equivalent weight of the polyalkylene oxide polymer may be from 100 g / mol to 2,000 g / mol, such as from 200 g / mol to 1,000 g / mol, such as from 400 g / mol to 800 g / mol. As used herein, with respect to polyalkylene oxide polymers, the "hydroxyl equivalent weight" is determined by dividing the molecular weight of the polyalkylene oxide polymer by the number of hydroxyl groups present in the polyalkylene oxide polymer.

[0068] Alternatively, the z-average molecular weight (M z ) may be at least 200 g / mol, such as at least 400 g / mol, such as at least 600 g / mol, and may be no more than 5,000 g / mol, such as no more than 3,000 g / mol, such as no more than 2,000 g / mol. According to the present disclosure, the polyalkylene oxide polymer may have a z-average molecular weight of 200 g / mol to 5,000 g / mol (such as 400 g / mol to 3,000 g / mol, such as 600 g / mol to 2,000 g / mol). As used herein, for a polymer having a z-average molecular weight (M) of less than 900,000 z ) of a polyalkylene oxide polymer, the term “z-average molecular weight (M z )" means the z-average molecular weight (M) as determined by gel permeation chromatography using the following z ): A Waters 2695 separation module with a Waters 410 differential refractometer (RI detector), polystyrene standards with molecular weights ranging from approximately 500 g / mol to 900,000 g / mol, tetrahydrofuran (THF) with 0.05 M lithium bromide (LiBr) at a flow rate of 0.5 mL / min as eluent, and an Asahipak GF-510HQ column were used for separation.

[0069] The polyalkylene oxide polymer may be present in the electrodepositable coating composition in an amount of at least 0.1 wt %, such as at least 0.5 wt %, such as at least 0.75 wt %, based on the total weight of the resin blend solids, and in some cases, may be present in the electrodepositable coating composition in an amount of no more than 10 wt %, such as no more than 4 wt %, such as no more than 3 wt %, based on the total weight of the resin blend solids. The polyalkylene oxide polymer may be present in the electrodepositable coating composition in an amount of 0.1 wt % to 10 wt %, such as 0.5 wt % to 4 wt %, such as 0.75 wt % to 3 wt %, based on the total weight of the resin blend solids.

[0070] According to the present disclosure, the coating composition that can be electrodeposited can include other optional ingredients, such as pigment composition and various additives (if desired), such as fillers, plasticizers, antioxidants, biocides, UV light absorbers and stabilizers, hindered amine light stabilizers, defoamers, fungicides, dispersing aids, flow control agents, surfactants, wetting agents or combinations thereof. Alternatively, the coating composition that can be electrodeposited can be completely free of any optional ingredients, i.e., the optional ingredients are not present in the coating composition that can be electrodeposited. The pigment composition can include, for example, iron oxide, lead oxide, strontium chromate, carbon black, coal powder, titanium dioxide, talcum, barium sulfate and color pigments such as cadmium yellow, cadmium red, chrome yellow. When using pigment, the pigment content of the dispersion can be expressed as the weight ratio of pigment to resin, and can be in the range of 0.03 to 0.6. According to the total weight of the resin solids of the coating composition that can be electrodeposited, the above-mentioned other additives can be each independently present in the coating composition that can be electrodeposited with an amount of 0.01 weight % to 3 weight %.

[0071] According to the present disclosure, the coating composition that can be electrodeposited can include water and / or one or more organic solvents. Based on the gross weight of the coating composition that can be electrodeposited, water can be present in an amount of, for example, 40% to 90% by weight (such as 50% to 75% by weight). The example of a suitable organic solvent includes an oxygenated organic solvent, such as a monoalkyl ether containing 1 to 10 carbon atoms in an alkyl group of ethylene glycol, diethylene glycol, propylene glycol and dipropylene glycol, such as the monoethyl ether and monobutyl ether of these glycols. Other examples of water-miscible solvents at least partially include alcohols, such as ethanol, isopropanol, butanol and diacetone alcohol. If used, based on the gross weight of the coating composition that can be electrodeposited, the organic solvent can generally be present in an amount less than 10% by weight (such as less than 5% by weight). The coating composition that can be electrodeposited can be provided specifically in the form of a dispersion (such as an aqueous dispersion).

[0072] According to the present disclosure, the total solid content of the electrodepositable coating composition may be at least 1 wt %, such as at least 5 wt %, and may be no more than 50 wt %, such as no more than 40 wt %, such as no more than 20 wt %, based on the total weight of the electrodepositable coating composition. The total solid content of the electrodepositable coating composition may be from 1 wt % to 50 wt %, such as from 5 wt % to 40 wt %, such as from 5 wt % to 20 wt %, based on the total weight of the electrodepositable coating composition. As used herein, "total solids" refers to the non-volatile content of the electrodepositable coating composition, i.e., materials that will not volatilize when heated to 110° C. for 15 minutes.

[0073] Substrate

[0074] According to the present disclosure, the coating composition that can be electrodeposited can be applied to the substrate electrophoretically. The coating composition that can be electrodeposited by cation can be deposited electrophoretically on any conductive substrate. Suitable substrates include metal substrates, metal alloy substrates and / or metallized substrates, such as nickel-plated plastics. Additionally, the substrate can include non-metallic conductive materials, including composite materials, such as materials that include carbon fiber or conductive carbon, for example. According to the present disclosure, the metal or metal alloy can include cold-rolled steel, hot-rolled steel, steel coated with zinc metal, zinc compounds or zinc alloys, such as electrogalvanized steel, hot-dip galvanized steel, alloyed hot-dip galvanized steel (galvanealed steel) and steel plated with zinc alloys. Aluminum alloys of 2XXX, 5XXX, 6XXX or 7XXX series and clad aluminum alloys and cast aluminum alloys of A356 series can also be used as substrates. Magnesium alloys of AZ31B, AZ91C, AM60B or EV31A series can also be used as substrates. The substrate used in the present disclosure can also include titanium and / or titanium alloys. Other suitable non-ferrous metals include copper and magnesium and alloys of these materials. Suitable metal substrates for use in the present disclosure include metal substrates commonly used in the following: vehicle body assemblies (such as, but not limited to, doors, body panels, trunk lids, roof panels, hoods, roofs and / or stringers, rivets, landing gear components and / or skins used on aircraft), vehicle frames, vehicle parts, motorcycles, wheels, industrial structures and components, such as household appliances including washers, dryers, refrigerators, stoves, dishwashers, etc., agricultural equipment, lawn and garden equipment, air conditioning units, heat pump units, lawn furniture and other articles. 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 metal substrate can also be in the form of, for example, metal sheets or prefabricated parts. It should also be understood that the substrate can be pretreated with a pretreatment solution comprising a zinc phosphate pretreatment solution, such as, for example, the zinc phosphate pretreatment solutions described in U.S. Pat. Nos. 4,793,867 and 5,588,989, each of which is incorporated herein by reference, or a zirconium-containing pretreatment solution, such as, for example, those described in U.S. Pat. Nos. 7,749,368 and 8,673,091, each of which is incorporated herein by reference.

[0075] Coating method, coating and coated substrate

[0076] The present disclosure also relates to a method for coating a substrate (such as any of the conductive substrates mentioned above). The method may include electrophoretically applying an electrodepositable coating composition as described above to at least a portion of the substrate and curing the coating composition to form an at least partially cured coating on the substrate. The method may include: (a) electrophoretically depositing the electrodepositable coating composition of the present disclosure onto at least a portion of the substrate; and (b) heating the coated substrate to a temperature and for a time sufficient to cure the electrodeposited coating on the substrate. The method may optionally further include: (c) directly applying one or more pigmented coating compositions and / or one or more non-pigmented coating compositions to the at least partially cured electrodeposited coating to form a top coating on at least a portion of the at least partially cured electrodeposited coating; and (d) heating the coated substrate of step (c) to a temperature and for a time sufficient to cure the top coating.

[0077] The composition can be deposited on a conductive substrate by contacting a coating composition that can be electrodeposited with a conductive cathode and a conductive anode, wherein the surface to be coated is a cathode. After contacting the composition, when enough voltages are applied between electrodes, the adhesion film of the coating composition is deposited on the cathode. The conditions for electrodeposition are similar to the conditions used in the electrodeposition of other types of coatings. The voltage applied can vary and can be, for example, as low as one volt to as high as several thousand volts, such as between 50 volts and 500 volts. The current density can be between 0.5 ampere and 15 amperes per square foot, and tends to reduce during electrodeposition, which shows that an insulating film has been formed.

[0078] Once the cationic electrodepositable coating composition is electrodeposited on at least a portion of the conductive substrate, the coated substrate is heated to a temperature and 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 the coating refers to forming a coating by subjecting the coating composition to curing conditions that chemically react at least a portion of the reactive groups of the components of the coating composition to form a coating. The coated substrate can be heated to a temperature ranging from 250°F to 450°F (121.1°C to 232.2°C), such as 275°F to 400°F (135°C to 204.4°C), such as 300°F to 360°F (149°C to 180°C). The curing time can depend on the curing temperature and other variables, for example, the film thickness of the electrodeposited coating, the level and type of the catalyst present in the composition, etc. For the purposes of this disclosure, all that is necessary is that the time is sufficient to achieve the curing of the coating on the substrate. For example, the curing time may range from 10 minutes to 60 minutes, such as 20 to 40 minutes. The thickness of the resulting cured electrodeposition coating may range from 15 to 50 microns.

[0079] The composition can be deposited on a conductive substrate by contacting an anion electro-depositable coating composition with a conductive cathode and a conductive anode, wherein the surface to be coated is an anode. After contacting the composition, when enough voltages are applied between electrodes, the adhesion film of the coating composition is deposited on the anode. The conditions for electrodeposition are similar to the conditions used in the electrodeposition of other types of coatings. The voltage applied can vary and can be, for example, as low as one volt to as high as several thousand volts, such as between 50 volts and 500 volts. The current density can be between 0.5 ampere and 15 amperes per square foot, and tends to reduce during electrodeposition, which shows that an insulating film has been formed.

[0080] Once the anionic electrodepositable coating composition is electrodeposited on at least a portion of the conductive substrate, the coated substrate can be heated to a temperature and 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 the coating refers to forming a coating by subjecting the coating composition to curing conditions that chemically react at least a portion of the reactive groups of the components of the coating composition to form a coating. The coated substrate can be heated to a temperature ranging from 200°F to 450°F (93°C to 232.2°C), such as 275°F to 400°F (135°C to 204.4°C), such as 300°F to 360°F (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 the catalyst present in the composition, etc. For the purposes of this disclosure, all that is necessary is that the time is sufficient to achieve the curing of the coating on the substrate. For example, the curing time can range from 10 to 60 minutes, such as 20 to 40 minutes. The thickness of the resulting cured electrodeposited coating may range from 15 to 50 microns.

[0081] If desired, the electrodepositable coating compositions of the present disclosure may also be applied to substrates using non-electrophoretic coating application techniques such as flow coating, dipping, spraying, and roller coating. For non-electrophoretic coating applications, the coating compositions may be applied to conductive substrates as well as non-conductive substrates such as glass, wood, and plastic.

[0082] The present disclosure further relates to coatings formed by at least partially curing the electrodepositable coating compositions described herein.

[0083] The present disclosure further relates to a substrate at least partially coated with an electrodepositable coating composition described herein in an at least partially cured state.

[0084] Multilayer coating composites

[0085] The electrodepositable coating composition of the present disclosure can be used for electrophoretic coating, which is a part of a multilayer coating composite material including a substrate with various coatings. The coating can include a pre-treatment layer, such as a phosphate layer (e.g., a zinc phosphate layer), an electrophoretic coating produced by an aqueous resin dispersion of the present disclosure, and a suitable top coating (e.g., a base coating, a clear coating, a pigmented monocoat and a color plus clear coating composite composition). It should be understood that suitable top coatings include any coatings in those coatings known in the art, and can be independently water-based, solvent-based, in the form of solid particles (i.e., a powder coating composition) or in the form of a powder slurry. The topcoat generally comprises a film-forming polymer, a cross-linking material, and one or more pigments (if it is a colored base coating or a monocoat). According to the present disclosure, a primer layer is placed between the electrophoretic coating and the base coating. According to the present disclosure, one or more top coatings in the top coating are applied to a substantially uncured bottom layer. For example, a clear coating can be applied to at least a portion of a substantially uncured base coating (wet-on-wet), and two layers can be cured simultaneously in a downstream process.

[0086] In addition, the top coating can be applied directly to the electrodepositable coating. In other words, the substrate lacks a primer layer. For example, the base coating can be applied directly to at least a portion of the electrodepositable coating.

[0087] It will also be understood that the topcoat can be applied to the bottom layer despite the fact that the bottom layer has not yet been fully cured. For example, a clearcoat can be applied to the basecoat even if the basecoat has not been subjected to a curing step. The two layers can then be cured during a subsequent curing step, thereby eliminating the need to separately cure the basecoat and the clearcoat.

[0088] According to the present disclosure, additional ingredients (such as colorants and fillers) may be present in various coating compositions that produce topcoats. Any suitable colorants and fillers may be used. For example, colorants may be added to the coating in any suitable form such as discrete particles, dispersions, solutions and / or flakes. Single colorants or mixtures of two or more colorants may be used in the coating of the present disclosure. It should be noted that colorants may be present in a certain layer of a multilayer composite material in any amount sufficient to impart desired properties, visual and / or color effects.

[0089] The electrodepositable coating compositions of the present disclosure may be substantially free, essentially free, or completely free of silica microspheres and / or silica nanospheres. As used herein, the electrodepositable coating composition is "substantially free" of silica microspheres and / or silica nanospheres if the silica microspheres and / or silica nanospheres, if any, are present in the electrodepositable coating composition in an amount of less than 3% by weight, based on the total weight of the resin solids. As used herein, the electrodepositable coating composition is "essentially free" of silica microspheres and / or silica nanospheres if the silica microspheres and / or silica nanospheres, if any, are present in the electrodepositable coating composition in an amount of less than 1% by weight, based on the total weight of the electrodepositable coating composition. As used herein, the electrodepositable coating composition is "completely free" of silica microspheres and / or silica nanospheres if the silica microspheres and / or silica nanospheres are not present in the electrodepositable coating composition, i.e., 0% by weight.

[0090] As used herein, unless otherwise defined, the term "substantially free" means that a component, if any, is present in an amount of less than 5 weight %, based on the total weight of the slurry composition.

[0091] As used herein, unless otherwise defined, the term "substantially free" means that a component, if any, is present in an amount of less than 1 wt %, based on the total weight of the slurry composition.

[0092] As used herein, unless otherwise defined, the term "completely free of" means that the component is not present in the electrodepositable coating composition, ie, 0.00 wt %, based on the total weight of the slurry composition.

[0093] For the purpose of this detailed description, it should be understood that the present disclosure may take alternative variations and step sequences except where explicitly stated to the contrary. In addition, except in any operating examples or where otherwise indicated, all numerals representing the amount of ingredients used in the specification and claims should be understood to be modified by the term "about" in all cases. Therefore, unless otherwise indicated, the numerical parameters set forth in the following specification and the appended claims are approximate values ​​that can be changed according to the desired properties to be obtained by the present disclosure. At least, and not attempting to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be interpreted according to the number of reported significant figures and by applying common rounding techniques.

[0094]

[0013] While the numerical ranges and parameters setting forth the broad scope of the present disclosure are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0095] Furthermore, it should be understood that any numerical range recited herein is intended to include all subranges subsumed therein. For example, a range of "1 to 10" is intended to include all subranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, i.e., having a minimum value equal to or greater than 1 and a maximum value equal to or less than 10.

[0096] As used herein, "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 unrecited elements, materials, ingredients, or method steps. As used herein, "consisting of" is understood in the context of this application to exclude the presence of any unspecified elements, ingredients, or method steps. As used herein, "consisting essentially of" is understood in the context of this application to include the specified elements, materials, ingredients, or method steps "as well as those elements, materials, ingredients, or method steps that do not materially affect the basic and novel characteristics of what is described."

[0097] As used herein, the terms "on", "onto", "appliedon", "applied onto", "formed on", "deposited on", "deposited onto" mean formed, covered, deposited or provided on a surface but not necessarily in contact with the surface. For example, a composition "deposited onto" a substrate does not exclude the presence of one or more other intermediate coatings of the same or different composition positioned between the electrodepositable coating composition and the substrate.

[0098] In this application, unless otherwise specifically stated, the use of the singular includes the plural, and the plural encompasses the singular. For example, although "a" hydroxyl-functionalized branched polymer product is mentioned herein, "a" film-forming polymer containing ionic salt groups, a combination of these components (i.e., a plurality of these components) different from the hydroxyl-functionalized branched polymer product may be used. In addition, in this application, unless otherwise specifically stated, the use of "or" means "and / or", even though "and / or" may be explicitly used in some cases.

[0099] Although specific aspects of the present disclosure have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details may be developed based on the overall teachings of the present disclosure. Therefore, the particular arrangements disclosed are intended to be illustrative only and not to limit the scope of the present disclosure, which is given by the full scope of the appended claims and any and all equivalent forms thereof.

[0100] The following examples illustrate the disclosure, which, however, should not be considered to limit the disclosure to its details. Unless otherwise indicated, all parts and percentages in the following examples and throughout the specification are by weight.

[0101] Examples Example 1: Blocked polyisocyanate crosslinker (crosslinker I) for electrodepositable coating compositions preparation .

[0102] The blocked polyisocyanate crosslinking agent (crosslinking agent I) suitable for electrodepositable coating resins is prepared in the following manner. Components 2-5 listed in the following table 1 are mixed in a flask set to total reflux by stirring under nitrogen. The mixture is heated to a temperature of 35°C, and component 1 is added dropwise so that the temperature rises and remains below 100°C due to the exothermic heat of reaction. After the addition of component 1 is completed, a temperature of 110°C is established in the reaction mixture, and the reaction mixture is maintained at this temperature until no residual isocyanate is detected by IR spectroscopy. Component 6 is then added and the reaction mixture is allowed to stir for 30 minutes and cooled to ambient temperature.

[0103] Table 1

[0104]

[0105]

[0106] 1 Rubinate M, available from Huntsman Corporation.

[0107] Example 2: Preparation of a cationic amine functionalized polyepoxide-based resin without additives (Comparative Resin Dispersion A) Preparation .

[0108] The cationic amine functionalized polyepoxide-based polymer resin suitable for the deployment of electrodepositable coating compositions is prepared in the following manner. By stirring under nitrogen, the components 1-5 listed in the following table 2 are mixed in a flask set to total reflux. The mixture is heated to 130°C and allowed to release heat (maximum 175°C). A temperature of 145°C is established in the reaction mixture, and the reaction mixture is then kept for 2 hours. Component 6 is introduced while allowing the mixture to cool to 125°C, and components 7 and 8 are then added. Components 9 and 10 are then quickly added to the reaction mixture, and the reaction mixture is made to release heat. A temperature of 122°C is established and the reaction mixture is kept for 1 hour to obtain a resin synthesis product A.

[0109] Table 2

[0110]

[0111]

[0112] 1 EPON 828, available from Hexion Corporation.

[0113] 2 See Example 1 above.

[0114] 3 The diketimine reaction product of 1 equivalent of diethylenetriamine and 2 equivalents of MIBK, 72.7 wt% (in MIBK).

[0115] A portion of the resin synthesis product A (component 11) was then poured into the premixed solution of components 12 and 13 to form a resin dispersion. Component 14 was then quickly added and the resin dispersion was stirred for 1 hour. Component 15 was then introduced over 30 minutes to further dilute the resin dispersion, followed by the addition of component 16. Free MIBK in the resin dispersion was removed from the dispersion under vacuum at a temperature of 60-70°C.

[0116] The solids content of the resulting cationic amine functionalized polyepoxide-based polymer resin dispersion (Comparative Resin Dispersion A) was determined by adding a certain amount of the resin dispersion to a tared aluminum pan, recording the initial weight of the resin dispersion, heating the resin dispersion in the pan at 110° C. in an oven for 60 minutes, allowing the pan to cool to ambient temperature, reweighing the pan to determine the amount of remaining non-volatile content, and calculating the solids content by dividing the weight of the remaining non-volatile content by the initial resin dispersion weight and multiplying by 100. (Note that this procedure was used to determine the solids content in each of the resin dispersion examples described below.) Comparative Resin Dispersion A had a solids content of 38.79 wt %. Example 3: Containing aliphatic Preparation of cationic amine functionalized polyepoxide based resins of polyols (experimental resin dispersions B and C) .

[0117] Cationic amine functionalized polyepoxide-based polymer resins suitable for preparing electrodepositable coating compositions are prepared in the following manner. Components 1-5 listed in Table 3 below are mixed in a flask set to total reflux by stirring under nitrogen. The mixture is heated to 130°C and allowed to release heat (maximum 175°C). A temperature of 145°C is established in the reaction mixture, and the reaction mixture is then kept for 2 hours. Component 6 is introduced while the mixture is allowed to cool to 125°C, and components 7 and 8 are then added. Components 9 and 10 are then quickly added to the reaction mixture, and the reaction mixture is made to release heat. A temperature of 122°C is established and the reaction mixture is kept for 1 hour to obtain resin synthesis products B and C, respectively.

[0118] Table 3

[0119]

[0120]

[0121] 1 EPON 828, available from Hexion Corporation.

[0122] 2 Vybar H-6164 / 6175 is a hydroxyl functionalized branched polymeric product commercially available from Baker Hughes.

[0123] 3 See Example 1 above.

[0124] 4 The diketimine reaction product of 1 equivalent of diethylenetriamine and 2 equivalents of MIBK, 72.7 wt% (in MIBK).

[0125] A portion of the resin synthesis product (B and C) (component 11) was then poured into the premixed solution of components 12 and 13 to form a resin dispersion. Component 14 was then quickly added and the resin dispersion was stirred for 1 hour. Component 15 was then introduced over 30 minutes to further dilute the resin dispersion, followed by the addition of component 16. Free MIBK in the resin dispersion was removed from the dispersion under vacuum at a temperature of 60-70°C.

[0126] The solids content of the resulting cationic amine functionalized resin dispersions was determined as described above in Example 2. Experimental resin dispersions B and C had solids contents of 38.79 wt % and 40.8 wt %, respectively.

[0127] Example 4: Preparation of cationic resin containing Jeffamine D400 (cationic resin D)

[0128] Table 4

[0129] serial number Components Weight (g) 1 <![CDATA[DER 732 1 ]]> 639.87 2 Bisphenol A 156.05 3 Butyl Carbitol Formaldehyde 7.96 4 Benzyl dimethylamine 1.50 5 Butyl Carbitol Formaldehyde 3.12 6 Butyl Carbitol Formaldehyde 49.46 7 <![CDATA[JEFFAMINE D400 2 ]]> 160.85 8 Butyl Carbitol Formaldehyde 7.96 9 <![CDATA[Diglycidyl Ether of Bisphenol A 3 > 17.38 10 Butyl Carbitol Formaldehyde 6.20 11 lactic acid 54.92 12 Deionized water 1225.50 13 <![CDATA[Rhodameen C5 4 ]]> 68.19 14 Deionized water 1132.45

[0130] 1 Aliphatic epoxy resin, available from Dow Chemical Co.

[0131] 2 Polypropylene oxide resin terminated with primary amines, available from Huntsman Chemical

[0132] 3 EPON 828, available from Hexion Corporation.

[0133] 4 Surfactants, available from Solvay

[0134] Cationic resins were prepared from the materials in Table 4 in the following manner: Materials 1-3 were added to a suitably equipped round-bottom flask. The mixture was then heated to 130°C. Materials 4-5 were then added. The reaction mixture was allowed to exotherm and maintained at 135°C until the epoxy equivalent reached 1230. The epoxy equivalent (EEW) was measured by potentiometric titration using 0.1N perchloric acid acetic acid solution as a titrant. A portion (~1 g) was sampled from the reaction mixture and dissolved in a 1:2 w / w mixture of dichloromethane / acetic acid (~30 mL). Tetraethylammonium bromide (~1 g) was then added to the solution and completely dissolved. The epoxy equivalent was then evaluated using a pre-programmed potentiometer equipped with an automatic titrant dispenser unit, a stirring plate, and a glass combination pH electrode, such as the Titrando series titrator available from Metrohm. 0.1N perchloric acid titrant was added under continuous pH monitoring until the pH of the sample dropped rapidly to a strongly acidic pH value and then stabilized, indicating that the titration was complete. EEW is calculated based on the determined endpoint, the mass of the aliquot and the equivalent of the titrant solution. Component 6 is then introduced while the contents of the flask are cooled to 100°C. Components 7-8 are added to the flask, the reaction mixture is allowed to exotherm and maintained at 90-95°C until a stable Gardner-Holdt viscosity GK is reached (10 g reaction mixture in 8.7 g 1-methoxy-2-propanol). The Gardner-Holdt viscosity is measured by filling a sample of the composition into a Gardern-Holdt tube (available from BYK-Gardner), leaving ~1 cm of air and sealing with a stopper. The tube is then placed in a 23°C water bath until the sample reaches this temperature. The sample is then placed in a stand with a reference tube (available from BYK-Gardner) and inverted. The viscosity is determined by a reference tube with a matching bubble rise rate. Components 9-10 are then introduced, and the reaction mixture is maintained at 90-95°C until a Gardner-Holdt viscosity of P is reached. The contents of the flask were dissolved into the premixed feeds 11-12 and mixed for 30 minutes. Feed 13 was then introduced and the resulting dispersion was mixed for an additional 30 minutes. At the end of the hold, component 14 was slowly added. The resulting cationic resin dispersion D had a solids content of 33.36%.

[0135] Example 5: Preparation of cationic resin intermediate (cationic resin intermediate I)

[0136] Table 5

[0137] serial number Components Weight (g) 1 Epon 828 8940.2 2 <![CDATA[Bisphenol A - ethylene oxide adduct 1 > 3242.1 3 Bisphenol A 2795.8 4 Methyl isobutyl ketone 781.8 5 <![CDATA[Tetronic 150R1 2 ]]> 8.1 6 Benzyl dimethylamine 12.4 7 Benzyl dimethylamine 18.24 8 <![CDATA[Diketone imine 3 > 1623.6 9 N-Methylethanolamine 758.7 10 Sulfamic acid 1524.4 11 Deionized water 12561 12 Deionized water 7170.3 13 Deionized water 11267.7 14 Deionized water 8450.7

[0138] 1 Bisphenol A 6 mole ethoxylate

[0139] 2Tetronic 150R1 is a nonionic surfactant available from BASF.

[0140] 3 The diketimine is the reaction product of diethylenetriamine and methyl isobutyl ketone in methyl isobutyl ketone at 72.3% solids.

[0141] Cationic resin intermediate I was prepared in the following manner using the components listed in Table 5. Materials 1-5 (Epon828, bisphenol A-ethylene oxide adduct, bisphenol A, methyl isobutyl ketone and Tetronic 150R1) were charged into a reaction vessel and heated to 125°C under a nitrogen atmosphere. The first portion of benzyl dimethylamine, i.e., material 6, was added and the reaction was allowed to exotherm to about 180°C. When the reaction reached 160°C, it was held for one hour. After the exothermic peak, the resin was allowed to cool back to 160°C and continued to be held. After holding, the reaction was then cooled to 130°C and the second portion of benzyl dimethylamine, i.e., material 7, was added. The reaction was held at 130°C until the extrapolated epoxy equivalent weight was 1070. At the expected epoxy equivalent weight, materials 8 and 9 (diketimine and N-methylethanolamine) were added continuously and the mixture was allowed to exotherm to about 150°C. At the exothermic peak, it was held for one hour while the reaction was allowed to cool to 125°C. After one hour of holding, the resin was dispersed in an aqueous medium consisting of aminosulfonic acid and the first portion of deionized water. The dispersion was subsequently reduced with the second, third, and fourth portions of deionized water. The resulting cationic soap was vacuum stripped until the methyl isobutyl ketone content was less than 0.05%.

[0142] Example 6: Preparation of cationic resin additive E

[0143] Table 6

[0144] serial number Components Weight (g) 1 Cationic resin intermediate I (Example 5) 50.10 2 Propylene glycol monopropyl ether 1.34 3 Deionized water 1.47 4 <![CDATA[Epon 828 solution 1 > 781.8 5 Ethylene glycol monobutyl ether 1.34 6 <![CDATA[Rhoadameen C5 2 ]]> 1.98 7 Deionized water 0.93 8 Deionized water 4.00 9 Deionized water 14.97

[0145] 1 85% Epon 828 (epoxy resin, available from Hexion Chemicals) + 15% propylene glycol methyl ether.

[0146] 2 Surfactants, available from Rhodia Chemicals

[0147] Cationic resin additive E was prepared in the following manner using the components listed in Table 6. Material 1 was charged to a reactor and heated to 70°C. Components 2 and 3 were introduced sequentially, and then material 4 was added over 15 minutes. Component 5 was added to the reaction mixture and held at 70°C for 45 minutes. The contents of the flask were then heated to 88°C and held for 3 hours. After a holding time of two and a half hours, components 6 and 7 were added. The heat source was removed from the reactor and material 8 was introduced. At 32°C, feed 9 was added and the mixture was held for 1 hour to obtain cationic resin additive E.

[0148] Preparation of electrodepositable coatings

[0149] Table 7

[0150]

[0151] 1 Available from BASF as MAZON 1651

[0152] 2 The slurry was supplied by PPG Industries and had a solids content of 52% and a pigment to binder weight ratio of 1.817, containing 1.6% dibutyltin oxide based on the total slurry weight.

[0153] For each coating composition, feeds 1-5 were added sequentially to a plastic container at room temperature with stirring, wherein each addition was followed by stirring for 10 minutes. The mixture was stirred at room temperature for at least 30 minutes. Feeds 6 and 7 were then added, and the coating was allowed to stir for a minimum of 30 minutes until uniform. Charge 8 was added, and the coating was allowed to stir for a minimum of 30 minutes until uniform. The resulting cationic electrodepositable coating composition had a solids content of 20.5%, determined as previously described, and a pigment to binder weight ratio of 0.12 / 1.0.

[0154] Coated panels were prepared from baths containing the respective cationic electrodepositable coating compositions after 20% ultrafiltration (and reconstitution with deionized water) and evaluated for pitting resistance. The results are reported below.

[0155] Oil stain resistance test

[0156] The above-described electrodepositable coating compositions were then electrodeposited onto cold rolled steel test panels, 4 x 6 x 0.031 inches, pretreated with CHEMFOS C700 / DI (CHEMFOS C700 is a zinc phosphate immersion pretreatment composition available from PPG Industries, Inc.). These panels are available from ACT Laboratories in Hillside, Mich. The panels were electrophoretically coated in a manner well known in the art by immersing the panels in a stirred bath at 32°C, connecting the cathode of a DC rectifier to the panels, and connecting the anode of the rectifier to a stainless steel tube for circulating cooling water for bath temperature control. The voltage was increased from 0 to a set point voltage between 160V-190V over a 30 second period, and then maintained at that voltage for an additional 120 seconds. This combination of time, temperature, and voltage provided a cured dry film thickness of 20 microns for all coatings.

[0157] After electrodeposition, the panels were removed from the bath and rinsed vigorously with a deionized water spray and cured by baking in an electric oven at 177 °C for 25 min.

[0158] The oil spot contamination resistance of the substrate panel containing the electrodeposited coating was tested, and the oil spot contamination resistance evaluated the ability of the electrodeposited coating to resist pit formation when solidified. The oil spot pitting resistance of the electrodeposited coating was tested by local contamination of the dried coating using three common oils: Ferrocote 6130 (Quaker Chemical Corporation, F), LubeCon Series O lubricant (Castrol Industrial North America Inc., L) or Molub-Alloy chain oil 22 spray (Castrol Industrial North America Inc., M). The oil was deposited on the dried coating in the form of droplets (<0.1 μL) using a 40 wt % solution of LubeCon Series O lubricant in isopropanol, a 40 wt % solution of Molub-Alloy chain oil 22 spray in isopropanol or a 40 wt % solution of Ferrocote 6130 in isopropanol / butanol (75 wt % / 25 wt %) and a micropipette (Scilogex). The oily patch substrate panels were then cured as described above (baked in an electric oven at 177°C for 20 minutes).

[0159] Each substrate panel was scanned using a Keyence VR-3200 optical measurement system to check the depth of the pit defects in the cured coating. The difference between the highest peak and the lowest pit point of each resulting pit in each coating (pit depth, Δ) was averaged (at least 4 pits per coating) to quantify the results of the oil spot test. Lower values ​​indicate improved performance. This test is referred to herein as the pit depth test method. The results show that both Vybar H-6164 and Vybar H-6175 showed improved performance in the pit depth test method compared to the comparative examples.

[0160] Table 8

[0161]

[0162] Alkyd Adhesion Testing

[0163] The white alkyd resin adhesion test evaluates the ability of the second cured coating to adhere to the cured electrodeposited coating below. The viscosity of the white alkyd resin coating C354-W404 available from PPG Industries, Inc. was reduced to 100 centipoise, as measured at room temperature (23°C) by a Brookfield DV-IPrime viscometer equipped with a cone and plate attachment at 20 rpm. The reducing solvent was butyl acetate. The electrophoretically coated test panels were prepared as described and baked in an electric oven at 155°C, 175°C, and 195°C for 25 minutes. The wet white alkyd resin coating was applied to the cured electrophoretic coating using a #55 (0.055 inch diameter wire) wound coating rod available from RD Specialties. After allowing the white alkyd resin coating to flash for 10 minutes under ambient conditions, the board was cured by baking horizontally in an electric oven at 150°C for 30 minutes. After the panels cooled to ambient temperature (about 25°C), they were subjected to a cross-hatch test.

[0164] The cross-hatch test uses a scribing tool with a tooth pitch set to 2 mm to cut the coating system into the metal substrate. By two such vertical cuts, a "cross-hatch" is produced, which is then tested with Scotch 898 tape. Failure is equivalent to the loss of adhesion between the alkyd coating and the electrodeposited coating. The cross-hatch adhesion results are tested on a scale of 0 to 10, with 0 being the worst and 10 being the best, and are reported in the table below. A score of 0 indicates that the cured alkyd coating has been completely removed from the scribing area by the tape. A score between 0 and 10 indicates that the tape gradually removes the less cured alkyd coating from the scribing area, and the coating is usually removed from the corner where the two scribing lines intersect. A score of 10 indicates that there is no evidence that the cured alkyd coating is removed by the tape from any corner where the two scribing lines intersect. A rating of 9 or 10 is considered to be a pass performance. As used herein, the test is referred to as the "white alkyd adhesion test". The results show that the comparative and experimental compositions performed similarly in the white alkyd test, while the experimental composition still showed improved performance in the above-described pit control test.

[0165] Table 9

[0166]

[0167] Those skilled in the art will appreciate that, based on the above disclosure, many modifications and variations are possible without departing from the broad inventive concepts described and illustrated herein. Therefore, it should be understood that the foregoing disclosure is only an illustration of various illustrative aspects of the present application, and those skilled in the art can easily make many modifications and variations within the spirit and scope of the present application and the appended claims.

Claims

1. An electrodepositable coating composition comprising: (a) hydroxyl-functionalized branched polymer products; (b) a film-forming polymer containing ionic salt groups different from the hydroxy-functional branched polymer product; and (c) Curing agent.

2. The electrodepositable coating composition of claim 1, wherein the hydroxyl-functionalized branched polymeric product comprises a branched poly-alpha-olefin.

3. The electrodepositable coating composition of claim 2, wherein the branched poly-alpha-olefin comprises constituent units comprising the residues of: (i) an alpha-olefin monomer having at least 6 carbon atoms; and (ii) Hydroxy-functional unsaturated monomers.

4. The electrodepositable coating composition of claim 3, wherein the branched poly-alpha-olefin comprises a polymerization product comprising the residue of: (i) an alpha-olefin monomer having at least 10 carbon atoms; and (ii) Hydroxy-functional unsaturated monomers.

5. The electrodepositable coating composition of claim 3, wherein the alpha-olefin monomer comprises an ethylenically unsaturated organic compound having at least six carbon atoms and a terminal carbon-carbon bond.

6. The electrodepositable coating composition of claim 5, wherein the ethylenically unsaturated organic compound has the structure H2C=CH-R, wherein R is a hydrocarbon group having at least four carbon atoms.

7. An electrodepositable coating composition according to claim 6, wherein R is an alkyl group.

8. The electrodepositable coating composition according to any one of claims 3 to 7, wherein the α-olefin monomer comprises a C6-C50 α-olefin.

9. The electrodepositable coating composition of any one of claims 4 to 8, wherein the α-olefin monomer comprises 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, or any combination thereof.

10. An electrodepositable coating composition according to any one of claims 3 to 9, wherein the hydroxyl functional unsaturated monomer comprises an α,β-unsaturated alcohol.

11. The electrodepositable coating composition of any one of claims 3 to 10, wherein the hydroxyl-functional unsaturated monomer comprises allyl alcohol, 5-hexen-1-ol, 3-hexen-1-ol, 4-penten-1-ol, 3-penten-1-ol, 3-buten-1-ol, crotyl alcohol, elaidic alcohol (9-trans-octadecene-1-ol), eicosanol (9-cis-eicosanol), 9-decen-1-ol, 9-dodecen-1-ol, 10-undecenol, oleyl alcohol (9-cis-octadecene-1-ol), erucyl alcohol (13-cis-eicosanol), basil alcohol (13-trans-eicosanol), ethoxylated and / or propoxylated derivatives thereof, acetates and formates of these alcohols, or any combination thereof.

12. The electrodepositable coating composition of any one of claims 3 to 11, wherein the molar ratio of alpha-olefin monomer to the hydroxyl functional unsaturated monomer is from 20:1 to 1:20, or from 10:1 to 1:10, or from 8:1 to 1:

2.

13. An electrodepositable coating composition according to any one of claims 3 to 12, wherein the polymer product is obtained by subjecting a mixture of the α-olefin monomer, the hydroxy-functional unsaturated monomer and at least one polymerization initiator to reaction conditions sufficient to copolymerize the α-olefin monomer and the hydroxy-functional unsaturated monomer.

14. The electrodepositable coating composition of claim 13, wherein the polymerization initiator comprises a free radical initiator comprising an organic peroxide.

15. An electrodepositable coating composition according to any one of the preceding claims, wherein the hydroxyl functionalized branched polymeric product has a hydroxyl equivalent weight of 50 to 3,000 g / eq.

16. An electrodepositable coating composition according to any one of the preceding claims, wherein the hydroxyl-functional branched polymeric product has a z-average molecular weight of 4,000 to 15,000 g / mol as determined by gel permeation chromatography using polystyrene calibration standards.

17. An electrodepositable coating composition according to any one of the preceding claims, wherein the hydroxyl-functional branched polymeric product has a number average molecular weight of 500 g / mol to 10,000 g / mol as determined by gel permeation chromatography using polystyrene calibration standards.

18. An electrodepositable coating composition according to any one of the preceding claims, wherein the film-forming polymer containing ionic salt groups comprises a film-forming polymer containing cationic salt groups.

19. An electrodepositable coating composition according to any one of the preceding claims 1 to 18, wherein the film-forming polymer containing ionic salt groups comprises a film-forming polymer containing anionic salt groups.

20. An electrodepositable coating composition according to any one of the preceding claims, wherein (a) the hydroxyl-functional branched polymeric product is present in an amount of 0.01 wt % to 10 wt %; (b) the film-forming polymer containing ionic salt groups is present in an amount of 40 wt % to 89.99 wt %; and (c) the curing agent is present in an amount of 10 wt % to 60 wt %, the wt % being based on the total weight of resin solids of the electrodepositable coating composition.

21. An electrodepositable coating composition according to any one of the preceding claims, wherein the curing agent comprises a polyisocyanate curing agent and the hydroxyl-functional branched polymeric product comprises a capping agent for the polyisocyanate curing agent.

22. An electrodepositable coating composition comprising: (a) the reaction product of a hydroxyl-functional branched polymer and a polyisocyanate; (b) a film-forming polymer containing ionic salt groups different from the hydroxy-functional branched polymer product; and (c) Optionally, (1) a curing agent different from the polyisocyanate, and / or (2) a polyisocyanate that does not include the hydroxy-functional branched polymer product as a capping agent.

23. An electrodepositable coating composition according to claim 21 or 22, wherein the hydroxyl-functional branched polymeric product comprises the hydroxyl-functional branched polymeric product of any one of the preceding claims 1 to 20.

24. An electrodepositable coating composition according to any one of claims 21 to 23, wherein the polyisocyanate has two isocyanate functional groups.

25. An electrodepositable coating composition according to any one of claims 21 to 24, wherein the ratio of hydroxyl functional groups from the hydroxyl functional branched polymeric product to isocyanato groups from the polyisocyanate is at least 2.45:1, such as at least 4.9:

1.

26. An electrodepositable coating composition comprising: (a) a film-forming polymer containing ionic salt groups; and (b) a polyisocyanate curing agent, wherein the polyisocyanate curing agent is at least partially end-capped with a hydroxyl-functional branched polymeric product.

27. The electrodepositable coating composition of claim 26, wherein the hydroxyl-functionalized branched polymeric product comprises the hydroxyl-functionalized branched polymeric product of any one of the preceding claims 1 to 20.

28. A method of coating a substrate comprising electrophoretically applying an electrodepositable coating composition according to any one of the preceding claims to at least a portion of the substrate.

29. A coated substrate having a coating, the coating comprising: (a) hydroxyl-functionalized branched polymer products; (b) a film-forming polymer containing ionic salt groups different from the hydroxy-functional branched polymer product; and (c) Curing agent.

30. The coated substrate of claim 29, wherein the coating is deposited from an electrodepositable coating composition according to any one of the preceding claims 1 to 27.

31. A coated substrate according to claim 29 or 30, wherein the coating on the substrate has a pit depth reduced by at least 10% as measured by the Pit Depth Test Method compared to a comparative electrodepositable coating composition having the same composition as the electrodepositable coating composition except that the hydroxyl-functionalized branched polymeric product is not included.

32. The coated substrate of any preceding claim 29 to 31, wherein the coating on the substrate has a pit depth of 15 microns or less as measured by the Pit Depth Test Method.

33. The coated substrate of any preceding claim 29 to 32, wherein the coating on the substrate has an adhesion rating of at least 9 as measured by the White Alkyd Adhesion Test.

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