Actinic radiation curable compositions and their use
View Patent ↗Actinic radiation curable compositions comprising at least one actinic radiation curable, cationically polymerizable compound and at least one cationic photoinitiator, may be stabilized by the use of a stabilizer which is a complex of a Lewis acid (other than a fluorine-containing boron compound) and a Lewis base.
1. An actinic radiation curable composition comprising:
(A) 40-80 weight % of at least one liquid epoxy resin having an epoxy functionality of 2 or greater;
(B) 0.1-10 weight % of at least one cationic photoinitiator;
(C) 5-40 weight % of at least one liquid diacrylate;
(D) 0-15 weight % of at least one liquid poly(meth) acrylate having a (meth)acrylate functionality of greater than 2;
(E) 0.1-15 weight % of at least one radical photoiniator;
(F) 5-40 weight % of at least one OH-terminated polyether, OH-terminated polyester or OH-terminated polyurethane; and
(G) 0.001-0.3 weight % of at least one stabilizer selected from the group consisting of borane ammoniac complex, borane triethylamine complex, borane tributylphosphine complex, borane trimethylamine complex, borane triphenylphosphine complex, borane tributylamine complex, borane N,N-diethylamine complex, borane N,N-diisopropyl ethylamine complex, borane dimethylamine complex, borane N-ethyl-N-isopropyl aniline complex, borane 4-methyl-morpholine complex, borane 4-ethylmorpholine complex, bis-(triethylborane) 1,6-diaminohexane complex, trichloroborane N,N-dimethyloctylamine complex, trichloroborane N,N-dimethyloctylamine complex, trichloroborane triethylamine complex, trichloroborane pyridine complex, trichloroborane benzylamine complex, irontrichloride triethylamine complex, irontrichloride pyridine complex, and irontrichloride N,N-dimethyloctylamine.
2. The actinic radiation curable composition of claim 1 wherein the stabilizer is selected from the group consisting of borane trimethylamine complex, borane tributylphosphine complex, borane ammoniac complex, bis-(triethylborane) 1,6-diaminohexane complex, trichloroborane triethylamine complex, trichloroborane pyridine complex, trichloroborane benzylamine complex, irontrichloride triethylamine complex, irontrichloride pyridine complex, and irontrichloride N,N-dimethyloctylamine.
3. The actinic radiation curable composition of claim 1 wherein the epoxy resin is a cycloaliphatic diepoxide.
4. The actinic radiation curable composition of claim 3 wherein the cycloaliphatic diepoxide has a monomer purity of 90% or higher.
5. The actinic radiation curable composition of claim 1 wherein two or more epoxy resins are present.
6. The actinic radiation curable composition of claim 5 wherein the two or more epoxy resins are cycloaliphatic diepoxides independently selected from the group consisting of bis(4-hydroxycyclohexyl)methane diglycidyl ether; 2,2-bis(4-hydroxycyclohexyl) propane diglycidyl ether; 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate; 3,4-epoxy-6-methyl-cyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate; di-(3,4-epoxycyclohexylmethyl) hexanedioate; di-(3,4-epoxy-6-methyl-cyclohexylmethyl) hexanediotate; ethylenebis(3,4-epoxycyclohexanecarboxylate), ethanediol di-(3,4-epoxycyclohexylmethyl) ether and 2-(3,4-epoxycyelohexyl-5,5,3-dioxane).
7. The actinic radiation curable composition of claim 1 wherein the cationic photoiniator is an onium salt with an anion of weak nucleophilicity.
8. The actinic radiation curable composition of claim 7 wherein the onium salt comprises an onium salt of formula (III), (IV) or (V):
wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 7 are independently selected from a C 6 -C 18 aryl which may be optionally substituted by appropriate radicals; A is CF 3 SO − 3 or an anion having the formula [LQ m ] − where L is selected from the group consisting of boron, phosphorus, arsenic and antimony; Q is a halogen or hydroxyl group; and m is an integer corresponding to the valency of L enlarged by 1.
9. The actinic radiation curable composition of claim 8 wherein the onium salt is a compound having formula (V) and R 5 , R 6 and R 7 are independently selected from the group of phenyl and biphenyl.
10. The actinic radiation curable composition of claim 1 wherein the OH-terminated polyether has a molecular weight ranging between 250 to 4000.
11. A method for producing a cured product comprising treating an actinic radiation curable composition according to claim 1 with actinic radiation.
12. A method for producing a stabilized actinic radiation curable composition comprising mixing:
(A) 40-80 weight % of at least one liquid epoxy resin having an epoxy functionality of 2 or greater;
(B) 0.1-10 weight % of at least one cationic photoinitiator;
(C) 5-40 weight % of at least one liquid diacrylate;
(D) 0-15 weight % of at least one liquid poly(meth)acrylate having a (meth)acrylate functionality of greater than 2;
(E) 0.1-15 weight % of at least one radical photoiniator;
(F) 5-40 weight % of at least one OH-terminated polyether, OH-terminated polyester or OH-terminated polyurethane; with
(G) 0.001-0.3 weight % of at least one stabilizer selected from the group consisting of borane ammoniac complex, borane triethylamine complex, borane tributylphosphine complex, borane trimethylamine complex, borane triphenylphosphine complex, borane tributylamine complex, borane N,N-diethylamine complex, borane N,N-diisopropyl ethylamine complex, borane dimethylamine complex, borane N-ethyl-N-isopropyl aniline complex, borane 4-methyl-morpholine complex, borane 4-ethylmorpholine complex, bis-(triethylborane)1,6-diaminohexane complex, trichloroborane N,N-dimethyloctylamine complex, trichloroborane N,N-dimethyloctylamine complex, trichloroborane triethylamine complex, trichloroborane pyridine complex, trichloroborane benzylamine complex, irontrichloride triethylamine complex, irontrichloride pyridine complex, and irontrichloride N,N-dimethyloctylamine.