Photocurable compositions for articles having stable tensile properties
View Patent ↗A photocurable composition comprising cationically curable compound, an acrylate-containing compound; a hydroxyl-containing compound; a cationic photoinitiator; and a free radical photoinitiator; wherein said composition has less than 0.54 equivalents of cationically curable groups, less than 0.10 equivalents of acrylate groups and less than 0.10 equivalents of hydroxyl groups per 100 grams of said composition.
1. A photocurable composition comprising:
(a) an cationically curable compound;
(b) an acrylate-containing compound;
(c) a hydroxyl-containing compound;
(d) a cationic photoinitiator; and
(e) a free radical photoinitiator;
wherein said composition has less than 0.54 equivalents of cationically curable groups, less than 0.10 equivalents of acrylate groups and between less than 0.10 to about 0.03 equivalents of hydroxyl groups per 100 grams of said composition.
2. The photocurable composition of claim 1 , wherein said cationically curable compound is an epoxy-containing compound, and said cationically curable groups are epoxy groups.
3. The photocurable composition of claim 2 , wherein said epoxy-containing compound is a difunctional non-glycidyl epoxy.
4. The photocurable composition of claim 3 , wherein said difunctional non-glycidyl epoxy is cycloaliphatic.
5. The photocurable composition of claim 4 , wherein said cycloaliphatic difunctional non-glycidyl epoxy is 3,4-epoxycyclohexylmethyl-3′,3′-epoxycclohexanecarboxylate.
6. The photocurable composition of claim 1 , wherein said acrylate-containing compound is a difunctional (meth)acrylate.
7. The photocurable composition of claim 6 , wherein said difunctional (meth)acrylate is aliphatic or aromatic.
8. The photocurable composition of claim 7 , wherein said difunctional (meth)acrylate is a bisphenol A-based epoxy diacrylate.
9. The photocurable composition of claim 1 , wherein said hydroxyl-containing compound is difunctional.
10. The photocurable composition of claim 9 , wherein said difunctional hydroxyl-containing compound is polyether polyol.
11. The photocurable composition of claim 10 , wherein said polyether polyol is a polytetramethylene glycol having a molecular weight of between 250 and 2000.
12. The photocurable composition of claim 1 , wherein said cationic photoinitiator is a mixture of S,S,S,S′-tetraphenylthiobis(4,1-phenylene)disulfonium dihexafluoroantimonate and diphenyl(4phenylthiophenyl)sulfonium hexafluoroantimonate.
13. The photocurable composition of claim 1 , wherein said free radical photoinitiator is a cyclohexyl phenyl ketone.
14. The photocurable composition of claim 13 , wherein said cyclohexyl phenyl ketone is 1-hydroxycyclohexyl phenyl ketone.
15. The photocurable composition of claim 1 , further comprising a reactive filler.
16. The photocurable composition of claim 15 , wherein said filler has a crosslinked polysiloxane core.
17. The photocurable composition of claim 1 , further comprising a stabilizer.
18. The photocurable composition of claim 17 , wherein said stabilizer is 2,6-di-tert-butyl-4-hydroxytoluene and/or N,N-dimethylbenzylamine.
19. The photocurable composition of claim 1 , which does not comprise any tn-functional or higher acrylates.
20. The photocurable composition of claim 1 , wherein said composition after imaging, curing and storage at 25° C. and 50% relative humidity has a tensile strength that increases by less than about 21% over 51 days.
21. The photocurable composition of claim 1 , wherein said composition after imaging, curing and storage at 25° C. and 50% relative humidity has a tensile modulus that increases by less than about 14% over 5.1 days.
22. The photocurable composition of claim 1 , wherein said composition after imaging, curing and storage at 25° C. and 50% relative humidity has an elongation at break that decreases by less than 47% over 51 days.
23. The photocurable composition of claim 1 , wherein said composition has about 0.46 to about 0.51 equivalents of cationically curable groups per 100 grams of said composition.
24. The photocurable composition of claim 1 , wherein said composition has about 0.048 to about 0.080 equivalents of acrylate groups per 100 grams of said composition.
25. The photocurable composition of claim 1 , wherein said composition has about 0.03 equivalents of hydroxyl groups per 100 grams of said composition.
26. A photocurable composition comprising:
(a) about 40% to about 80% by weight of a difunctional non-glycidyl epoxy;
(b) about 15% to about 35% by weight of a difunctional (meth)acrylate;
(c) about 10% to about 20% by weight of a difunctional hydroxyl-containing compound;
(d) a cationic photoinitiator; and
(e) a free radical photoinitiator
wherein said composition has less than 0.54 equivalents of cationically curable groups, less than 0.10 equivalents of acrylate groups and between less than 0.10 to about 0.03 equivalents of hydroxyl groups per 100 grams of said composition.
27. The photocurable composition of claim 26 , wherein said difunctional non-glycidyl epoxy is a cycloaliphatic epoxy.
28. The photocurable composition of claim 27 , wherein said cycloaliphatic difunctional non-glycidyl epoxy is 3,4-epoxycyclohexylmethyl-3′,3′-epoxycclohexanecarboxylate.
29. The photocurable composition of claim 26 , wherein said difunctional (meth)acrylate is aliphatic or aromatic.
30. The photocurable composition of claim 29 , wherein said difunctional (meth)acrylate is a bisphenol A-based epoxy diacrylate.
31. The photocurable composition of claim 26 , wherein said difunctional hydroxyl-containing compound is polyether polyol.
32. The photocurable composition of claim 31 , wherein said polyether polyoi is a polytetramethylene glycol having a molecular weight of between 250 and 2000.
33. The photocurable composition of claim 26 , wherein said cationic photoinitiator is a mixture of S,S,S,S′-tetraphenyhhiobis(4,1-phenylene)disulfonium dihexafluoroantimonate and diphenyl(4phenylthiophenyl)sulfonium hexafluoroantimonate.
34. The photocurable composition of claim 26 , wherein said free radical photoinitiator is a cyclohexyl phenyl ketone.
35. The photocurable composition of claim 34 , wherein said cyclohexyl phenyl ketone is 1-hydroxycyclohexyl phenyl ketone.
36. The photocurable composition of claim 26 , further comprising 0 to 12% by weight of a glycidyl ether.
37. The photocurable composition of claim 26 , further comprising 0 to 10% by weight of a reactive filler.
38. The photocurable composition of claim 37 , wherein said filler has a crosslinked polysiloxane core.
39. The photocurable composition of claim 26 , further comprising a stabilizer.
40. The photocurable composition of claim 39 , wherein said stabilizer is 2,6-di-tert-butyl-4-hydroxytoluene and/or N,N-dimethylbenzylamine.
41. The photocurable composition of claim 26 , which does not comprise any tn-functional or higher acrylates.
42. The photocurable composition of claim 26 , wherein said composition after imaging, curing and storage at 25° C. and 50% relative humidity has a tensile strength that increases by less than about 21% over 51 days.
43. The photocurable composition of claim 26 , wherein said composition after imaging, curing and storage at 25° C. and 50% relative humidity has a tensile modulus that increases by less than about 14% over 51 days.
44. The photocurable composition of claim 26 , wherein said composition after imaging, curing and storage at 25° C. and 50% relative humidity has an elongation at break that decreases by less than 47% over 51 days.
45. A paste comprising a curable reactive wax and the photocurable composition of claim 1 .
46. The paste of claim 45 , wherein the curable, reactive wax includes a reactive moiety selected from the group consisting of hydroxyl, carboxyl, isocyanate, thiol, amino, epoxy, and vinyl.