Cationically photocurable epoxy resin compositions
View Patent ↗The present invention provides a cationically photocurable epoxy resin composition, which contains (a) an epoxy resin component comprising an alicyclic epoxy resin and an aromatic-ring containing epoxy resin, (b) a cationic photoinitiator component, and (c) a filler selected from oxides, hydroxides and carbonates containing a Group II element. This composition exhibits improved adhesive strength to a glass such as an alkali glass, particularly a sodium-containing glass, or a metal.
1. A cationically photocurable epoxy resin composition comprising:
(a) an epoxy resin component comprising the combination of an alicyclic epoxy resin in an amount of about 1% to about 40% by weight of the epoxy resin component and non-fluorinated aromatic-ring containing epoxy resin in an amount of at least 60% by weight of the epoxy resin component;
(b) a cationic photoinitiator component;
(c) a filler having a particle size in the range of 0.5 to 15 μm selected from the group consisting of talc, Mg(OH) 2 and mixtures thereof; and
(d) silica.
2. The composition as claimed in claim 1 wherein (b) the cationic photoinitiator component comprises a salt represented by A + B − in which the anion B − is SbF 6 − or B(aryl) 4 − .
3. The composition as claimed in claim 2 wherein (b) the cationic photoinitiator component further comprises an initiator represented by A + B 31 in which the anion B − is other than SbF 6 − or B(aryl) 4 − ,in addition to the initiator represented by A + B − in which the anion B − is SbF 6 − or B(aryl) 4 − .
4. The composition as claimed in claim 3 , wherein the initiator in which the anion B − is other than SbF 6 − or B(aryl) 4 − is an initiator in which the anion B − is selected from the group consisting of PF 6 − , AsF 6 − and BF 4 − .
5. The composition as claimed in claim 1 , wherein the filler in (c) is talc.
6. The composition as claimed in claim 5 , wherein the silica is present in an amount greater than an amount of talc.
7. The composition as claimed in claim 1 , further comprising a silane coupling agent.
8. The composition as claimed in claim 1 , wherein the aromatic-ring containing epoxy resin comprises at least one selected from the group consisting of bisphenol epoxy resins, novolac epoxy resins and biphenyl epoxy resins; and the alicyclic epoxy resin comprises at least one selected from the compounds having cyclohexene oxide or cyclopentene oxide structure in molecule.
9. The composition as claimed in claim 1 , wherein the epoxy resin component consists essentially of non-fluorinated resins.
10. The composition as claimed in claim 1 , disposed as an adhesive between two substrates, at least one of which is an alkali glass or metal.
11. The composition as claimed in claim 1 , disposed as an adhesive between two substrates, at least one of which is an alkali glass.
12. The composition as claimed in claim 1 , wherein the epoxy resin component further comprises a diluent.
13. A cationically photocurable epoxy resin composition comprising:
(a) an epoxy resin component comprising the combination of an alicyclic epoxy resin in an amount of about 1% to about 40% by weight of the epoxy resin component and an aromatic-ring containing epoxy resin in an amount of at least 60% by weight of the epoxy resin component;
(b) a cationic photoinitiator component comprising a first initiator represented by A + B − , in which the anion B − is SbF 6 − or B(aryl) 4 − and a second initiator represented by A + B − in which the anion B − is other than SbF 6 − or B(aryl) 4 − ;
(c) a filler having a particle size in the range of 0.5 to 15 μm selected from the group consisting of talc, Mg(OH) 2 and mixtures thereof; and
(d) silica.
14. The composition as claimed in claim 13 , wherein the epoxy resin component consists essentially of non-fluorinated resins.
15. A cationically photocurable epoxy resin composition comprising:
(a) an epoxy resin component comprising the combination of an alicyclic epoxy resin in an amount of about 1% to about 40% by weight of the epoxy resin component and an aromatic-ring containing epoxy resin in an amount of at least 60% by weight of the epoxy resin component;
(b) a cationic photoinitiator component comprising a first initiator represented by A + B − in which the anion B − is SbF 6 − or B(aryl) 4 − and a second initiator represented by A + B − in which the anion B − is selected from the group consisting of PF 6 − , AsF 6 − and BF 4 − ;
(c) a filler having a particle size in the range of 0.5 to 15 μm selected from the group consisting of talc, Mg(OH) 2 and mixtures thereof; and
(d) silica.
16. The composition as claimed in claim 15 , wherein the epoxy resin component consists essentially of non-fluorinated resins.