Polyvinyl ester-based latex coating compositions
View Patent ↗Embodiments of the present disclosure include a polyvinyl ester-based latex having polyvinyl ester-based particles with vinyl ester groups that have been partially hydrolyzed to a predetermined degree, and methods of modifying and forming the polyvinyl ester-based latex of the present disclosure. Embodiments of the present disclosure also include coating compositions that include the polyvinyl ester-based latex of the present disclosure and an optical brightening agent (OBA), where the polyvinyl ester-based particles act as a carrier for the OBA in a coating composition for a print media substrate.
1. A coating composition, comprising:
a polyvinyl ester-based latex comprising polyvinyl ester-based particles with vinyl ester groups partially hydrolyzed to a predetermined degree, wherein the predetermined degree of hydrolysis is from about 10 to about 50 percent of the vinyl ester groups; and
an optical brightening agent, wherein the polyvinyl ester-based particles act as a carrier for the optical brightening agent.
2. The composition of claim 1 wherein the polyvinyl ester-based latex comprises a polyvinyl acetate-based latex comprising acetate groups partially hydrolyzed to a predetermined degree.
3. The coating composition of claim 1 , further comprising a binder, wherein the polyvinyl ester-based particles and the binder are present in an amount from about 0.125 to about 3 parts of polyvinyl ester-based particles to binder, and the binder is selected from the group consisting of styrene butadiene, carboxylated styrene butadiene, styrene butadiene acrylonitrile, carboxylated styrene butadiene acrylonitrile, styrene acrylate, carboxylated styrene acrylate, (carboxymethyl)cellulose, starch, polyvinyl alcohol, polyvinyl acetate homopolymers and copolymers, ethylene vinyl acetate copolymers, and combinations thereof.
4. The coating composition claim 3 , further comprising a pigment, wherein the polyvinyl ester-based particles and the binder are present in an amount from about 3 parts to about 25 parts of combined polyvinyl ester-based particles and binder per 100 parts pigment.
5. The coating composition of claim 1 , wherein the polyvinyl ester-based particles comprise homopolymers or copolymers formed from monomers selected from the group consisting of vinyl acetate, vinyl propionate, and vinyl butyrate.
6. The coating composition of claim 1 , wherein the polyvinyl ester-based particles comprise copolymers formed from monomers selected from the group consisting of vinyl acetate, vinyl propionate, vinyl butyrate, and at least one other dissimilar monomer.
7. A method of preparing the coating composition of claim 1 , comprising:
providing a polyvinyl ester-based latex comprising polyvinyl ester-based particles that comprise vinyl ester groups; and
partially hydrolyzing a predetermined percentage of the vinyl ester groups of the polyvinyl ester-based particles.
8. The coating composition of claim 1 , wherein the coating composition is substantially free of polyvinyl alcohol.