Curable composition, cured coating film prepared from curable composition, and printed wiring board including the cured film
A curable composition to be used for a printed wiring board is disclosed, which has an excellent flexibility and an excellent adhesive property with respect to both a plastic substrate and a conductive layer in the printed wiring board. The curable composition includes (A) a (meth)acrylate compound having a polyene structure, (B) a (meth)acrylate compound having a hydroxyl group; and (C) a photopolymerization initiator. From the curable composition, a cured coating film, and a printed wiring board including the cured coating film in the form of a predetermined pattern are obtained.
1. A curable composition for a printed wiring board, comprising:
(A) a (meth)acrylate compound having a polyene structure;
(B) a (meth)acrylate compound having a hydroxyl group;
(C) a photopolymerization initiator; and
(D) at least one diol diacrylate having an alkylene chain selected from the group consisting of 1,9-nonanediol diacrylate and 1,10-decanediol diacrylate.
2. The curable composition for a printed wiring board as claimed in claim 1 , wherein the polyene structure in the (meth)acrylate compound (A) is prepared by homopolymerization of butadiene or isoprene, or copolymerization of butadiene with isoprene.
3. The curable composition for a printed wiring board as claimed in claim 2 , wherein the polyene structure contained in the (meth)acrylate compound (A) as a repeating unit is represented by general formula (I):
wherein n is an integer in the range of 10 to 300.
4. The curable composition for a printed wiring board as claimed in claim 1 , further comprising a thermosetting component.
5. The curable composition for a printed wiring board as claimed in claim 1 , wherein the curable composition has a viscosity at 50° C. in the range of 5 to 50 mPa·s.
6. A cured coating film obtained by irradiating light to the curable composition according to claim 1 .
7. A printed wiring board comprising:
a substrate; and
a cured coating film in the form of a predetermined pattern, prepared by printing the substrate with the curable composition according to claim 1 , and
irradiating a light to the curable composition.
8. The printed wiring board as claimed in claim 7 , wherein the printing is performed by inkjet printing method.
9. The printed wiring board as claimed in claim 7 , wherein the substrate is made of a plastic.
10. The curable composition for a printed wiring board as claimed in claim 1 , wherein (D) the at least one diol diacrylate is 1,10-decanediol diacrylate.
11. The curable composition for a printed wiring board as claimed in claim 1 , wherein (D) the at least one diol diacrylate comprises 1,9-nonanediol diacrylate and 1,10-decanediol diacrylate.
12. The curable composition for a printed wiring board as claimed in claim 1 , wherein (D) the at least one diol diacrylate is 1,9-nonanediol diacrylate.
13. The curable composition for a printed wiring board as claimed in claim 1 , wherein (A) the (meth)acrylate compound comprises at least one of isophorone isocyanate-modified urethane acrylate and acrylic modified butadiene, (B) the (meth)acrylate compound comprises at least one of 2-hydroxyethyl methacrylate and 4-hydroxybutyl acrylate, (C) the photopolymerization initiator comprises at least one of 2-hydroxy-2-methyl-1-phenyl-propane-1-one, 2-ethyl anthraquinone and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, and (D) the at least one diol diacrylate comprises 1,9-nonanediol diacrylate.
14. The curable composition for a printed wiring board as claimed in claim 13 , wherein (A) the (meth)acrylate compound is included in an amount of 10 to 45 wt. %.
15. The curable composition for a printed wiring board as claimed in claim 14 , wherein (B) the (meth)acrylate compound is included in an amount of 10 to 30 parts by weight based on 100 parts by weight of the curable composition.
16. The curable composition for a printed wiring board as claimed in claim 15 , wherein (C) the photopolymerization initiator is included in an amount of 0.5 to 10 wt. % with respect to the curable composition.
17. The curable composition for a printed wiring board as claimed in claim 16 , wherein (D) the at least one diol diacrylate is included in an amount of 20 to 80 parts by weight based on 100 parts by weight of the composition.
18. The curable composition for a printed wiring board as claimed in claim 17 , wherein (D) the at least one diol diacrylate is included in an amount of 40 to 70 parts by weight based on 100 parts by weight of the composition.
19. The curable composition for a printed wiring board as claimed in claim 17 , wherein (D) the at least one diol diacrylate is included in an amount of 40 to 60 parts by weight based on 100 parts by weight of the composition.
20. The curable composition for a printed wiring board as claimed in claim 17 , wherein (D) the at least one diol diacrylate is included in an amount of 50 to 55 parts by weight based on 100 parts by weight of the composition.