Aqueous coating composition and process

Claim 2

A coating composition in aqueous dispersion for forming a curable film thereof on a substrate comprising: (a) a water-solubilized positively charged polymer produced from one having at least about 5% by weight pendant mercaptan groups; and (b) at least about 5% by weight of said polymer of an alpha-, beta-ethylenically unsaturated carbonyl cross-linking agent having at least two pendant alpha-, beta-ethylenically unsaturated carbonyl groups, said cross-linking agent for cross-linking said polymer by addition polymerization upon subsequent curing of said curable film on said substrate.

Claim 3

The coating composition of claim 1 wherein said curable film on said substrate cures upon heating.

Claim 4

The coating composition of claim 1 wherein said composition contains at least about 0.5% by weight of said polymer of an ultraviolet photosensitizer and said curable film cures upon exposure to ultraviolet radiation.

Claim 5

The coating composition of claim 1 wherein said curable film cures upon exposure to ionizing radiation.

Claim 6

The coating composition of claim 1 wherein said polymer also has a minor proportion of pendant amine groups which are protonated with proton-donating acid for water solubilizing said polymer.

Claim 7

The coating composition of claim 1 wherein said cross-linking agent is an acrylate cross-linking agent having at least two pendant acrylate groups.

Claim 8

The coating composition of claim 1 wherein said cross-linking agent is an acrylamide cross-linking agent having at least two pendant acrylamide groups.

Claim 9

A cathodic electrocoating composition dispersed in an aqueous electrocoating bath for electrodeposition onto a cathode substrate disposed within said bath for forming a curable electrodeposited coating on said cathode substrate, comprising: (a) a water-solubilized positively charged polymer produced from one having at least about 5% by weight pendant mercaptan groups; and (b) at least about 5% by weight of said polymer of an alpha-, beta-ethylenically unsaturated carbonyl cross-linking agent having at least two pendant alpha-, beta-ethylenically unsaturated carbonyl groups, said cross-linking agent for cross-linking said polymer by addition polymerization upon subsequent curing of said curable coating on said cathode substrate.

Claim 10

A cathodic electrocoating composition dispersed in an aqueous electrocoating bath for electrodeposition onto a cathode substrate disposed within said bath for forming a curable electrodeposited coating on said cathode substrate, comprising: (a) a water-solubilized positively charged polymer produced from one having at least about 5% by weight pendant mercaptan groups; and (b) at least about 5% by weight of said polymer of an alpha-, beta-ethylenically unsaturated carbonyl cross-linking agent having at least two pendant alpha-, beta-ethylenically unsaturated carbonyl groups, said cross-linking agent for cross-linking said polymer by addition polymerization upon subsequent curing of said curable coating on said cathode substrate.

Claim 11

The cathodic electrocoating composition of claim 8 wherein said electrodeposited coating on said cathode substrate cures upon heating.

Claim 12

The cathodic electrocoating composition of claim 8 wherein said composition contains at least about 0.5% by weight of said polymer of an ultraviolet photosensitizer and said electrodeposited coating cures upon exposure to ultraviolet radiation.

Claim 13

The cathodic electrocoating composition of claim 8 wherein said electrodeposited coating cures upon exposure to ionizing radiation.

Claim 14

The cathodic electrocoating composition of claim 8 wherein said electrocoating polymer also has pendant amine groups which are protonated with proton-donating acid for solubilizing said polymer on said aqueous bath, said protonated amine groups adapted to become deprotonated by electrodeposition of said polymer onto said cathode substrate.

Claim 15

A cathodic electrocoating composition dispersed in an aqueous electrocoating bath for electrodeposition onto a cathode substrate disposed within said bath for forming a curable electrodeposited coating on said cathode substrate, comprising: (a) a water-solubilized positively charged polymer produced from one having at least about 5% by weight pendant mercaptan groups; and (b) at least about 5% by weight of said polymer of an acrylate cross-linking agent having at least two pendant acrylate groups; and said cross-linking agent for cross-linking said polymer by addition polymerization upon subsequent curing of said curable coating on said cathode substrate.

Claim 16

A cathodic electrocoating composition dispersed in an aqueous electrocoating bath for electrodeposition onto a cathode substrate disposed within said bath for forming a curable electrodeposited coating on said cathode substrate, comprising: (a) a water-solubilized positively charged polymer produced from one having at least about 5% by weight pendant mercaptan groups; and (b) at least about 5% by weight of said polymer of an acrylate cross-linking agent having at least two pendant acrylate groups; and said cross-linking agent for cross-linking said polymer by addition polymerization upon subsequent curing of said curable coating on said cathode substrate.

Claim 17

A cathodic electrocoating composition dispersed in an aqueous electrocoating bath for electrodeposition onto a cathode substrate diposed within said bath for forming a curable electrodeposited coating on said cathode substrate, comprising: (a) a water-solubilized positively charged polymer produced from one having at least about 5% by weight pendant mercaptan groups; and (b) at least about 5% by weight of said polymer of an acrylamide cross-linking agent having at least two pendant acrylamide groups; and said cross-linking agent for cross-linking said polymer by addition polymerization upon subsequent curing of said curable coating on said cathode substrate.

Claim 18

A cathodic electrocoating composition dispersed in an aqueous electrocoating bath for electrodeposition onto a cathode substrate diposed within said bath for forming a curable electrodeposited coating on said cathode substrate, comprising: (a) a water-solubilized positively charged polymer produced from one having at least about 5% by weight pendant mercaptan groups; and (b) at least about 5% by weight of said polymer of an acrylamide cross-linking agent having at least two pendant acrylamide groups; and said cross-linking agent for cross-linking said polymer by addition polymerization upon subsequent curing of said curable coating on said cathode substrate.

Claim 19

The coating composition of claim 1 wherein said polymer contains sulfonium ion groups for water solubilizing said polymer.

Claim 20

The cathodic electrocating composition of claim 13 wherein said electrocoating polymer contains sulfonium ion groups for water solubilizing said polymer.