Jet ink and ink jet printing process
An ink jet-printable composition, which comprises a compound having a reactive silyl group and which is suitable for printing on non-porous substrates such as a glass or ceramic, and a process of decorating non-porous substrates involving ink jet printing the composition onto the substrate, exposing the printed composition to actinic or electron beam radiation to initiate curing and heating the printed composition to a temperature of at least 100° C.
1. A process of decorating a glass or ceramic substrate, comprising:
a) ink jet printing a curable composition comprising (i) a compound having a reactive silyl group; (ii) a polymerizable monomer that does not include a reactive silyl group; and iii) an acidic component having an acid value of 50 to 300 mg KOH/g onto a substrate;
b) exposing the printed composition on the substrate to electron beam or actinic radiation to initiate curing; and
c) heating the exposed composition on the substrate to a temperature of 100° C. to 400° C. to provide a printed and cured ink;
wherein the printed and cured ink is resistant to removal from the substrate by exposure to alkali; and
wherein resistance to removal by exposure to alkali means that the printed and cured ink is not removed with greater than 100 alkali rubs.
2. The process of claim 1 , wherein the exposed composition is heated in step (c) to a temperature of at least 140° C.
3. The process of claim 1 , wherein the polymerizable monomer that does not include a reactive silyl group is a free radical-curable monomer.
4. The process of claim 1 , wherein the curable composition comprises a free radical photoinitiator and the printed composition is exposed to actinic radiation in step (b) to activate the photoinitiator.
5. The process of claim 1 , wherein the curable composition comprises a colorant.
6. The process of claim 5 , wherein the colorant is an inorganic pigment.
7. The process of claim 1 , wherein the exposed composition is heated in step (c) to a temperature of less than 400° C.
8. The process of claim 1 , wherein the curable composition is free of an acid-generating catalyst.
9. The process of claim 1 , wherein the curable composition comprises an epoxy monomer containing an epoxide functional group.
10. The process of claim 1 , wherein the compound having a reactive silyl group has a single reactive silyl group.
11. A process of decorating a glass or ceramic substrate comprising the steps of:
a) ink jet printing a curable composition comprising a compound having a reactive silyl group, a polymerizable monomer that does not include a reactive silyl group, and an acidic component having an acid value of 50 to 300 mg KOH/g onto a substrate;
b) exposing the printed composition on the substrate to electron beam or actinic radiation to initiate curing; and
c) heating the exposed composition on the substrate to a temperature of 100° C. to 400° C. to provide a printed and cured ink,
wherein the curable composition has a viscosity less than or equal to 50 cP at 25° C.;
wherein the printed and cured ink is resistant to removal from the substrate by exposure to alkali; and
wherein resistance to removal by exposure to alkali means that the printed and cured ink is not removed with greater than 100 alkali rubs.
12. The process of claim 11 , wherein the polymerizable monomer that does not include a reactive silyl group is a free radical-curable monomer.
13. The process of claim 11 , wherein the curable composition comprises a free radical photoinitiator and the printed composition is exposed to actinic radiation in step (b) to activate the photoinitiator.
14. The process of claim 11 , wherein the composition comprises a colorant, the colorant optionally comprising an inorganic pigment.
15. The process of claim 11 , wherein the curable composition is free of an acid-generating catalyst.
16. The process of claim 11 , wherein the curable composition comprises an epoxy monomer containing an epoxide functional group.
17. The process of claim 11 , wherein the compound having a reactive silyl group has a single reactive silyl group.