Ultraviolet-curable resin composition, ultraviolet-curable coating and coated article
The present invention is to provides an ultraviolet-curable resin composition which contains a composite resin (A) having a polysiloxane segment (a1) having a silanol group and/or a hydrolytic silyl group as well as a polymerizable double bond and a polymer segment (a2) other than the polysiloxane segment (a1), and a photo initiator (B). The ultraviolet-curable resin composition is able to form a cured coating film excellent in weatherability such as scratch resistance, acid resistance, alkali resistance and solvent resistance, without heating.
1. An ultraviolet-curable resin composition which comprises
a composite resin (A) which has a polysiloxane segment (a1) having a silanol group and/or a hydrolytic silyl group, as well as a polymerizable double bond and a polymer segment (a2) other than the polysiloxane segment (a1);
a photo initiator (B); and
a polyfunctional (meta) acrylate,
wherein the polysiloxane segment (a1) is a polysiloxane segment having a structural unit expressed by the following general formula (S-2) and (S-3),
(in the general formulae (S-2) and (S-3), R 3 , R 4 and R 5 each independently denotes an alkyl group of 1 to 6 carbon atoms, a cycloalkyl group or an aryl group of 3 to 8 carbon atoms and an aralkyl group of 7 to 12 of carbon atoms), and
wherein the composite resin (A) is a composite resin in which the polysiloxane segment (a1) is bonded to the polymer segment (a2) in a structure expressed by the formula (S-5)
(in the formula, the carbon atom is a carbon atom constituting the polymer segment (a2), and two silicon atoms are silicon atoms constituting the polysiloxane segment (a1)).
2. The ultraviolet-curable resin composition according to claim 1 , wherein the polysiloxane segment (a1) is a polysiloxane segment in which polymerizable double bonds are contained from 1 to 40% by weight on the basis of the weight of the polysiloxane segment.
3. The ultraviolet-curable resin composition according to claim 1 , wherein the polysiloxane segment (a1) is contained from 10 to 95% by weight with respect to the composite resin (A).
4. The ultraviolet-curable resin composition according to claim 1 , wherein the polymer segment (a2) is a vinyl polymer segment and/or a polyurethane polymer segment.
5. The ultraviolet-curable resin composition according to claim 1 , further comprises an organic solvent.
6. The ultraviolet-curable resin composition according to claim 1 , wherein the composite resin (A) is a composite resin having an anionic group.
7. The ultraviolet-curable resin composition according to claim 6 , wherein the anionic group is a neutralized carboxyl group.
8. The ultraviolet-curable resin composition according to claim 6 , wherein the anionic group is contained from 0.1 to 20% by weight on the basis of the weight of the composite resin (A).
9. The ultraviolet-curable resin composition according to claim 6 , further comprises water.
10. The ultraviolet-curable resin composition according to claim 1 , wherein the photo initiator (B) is one or more photo initiators which are selected from the group consisting of acetophenones, benzyl ketals, benzophenones and benzoins.
11. The ultraviolet-curable resin composition according to claim 10 , wherein the photo initiator (B) is contained from 0.1 to 20% by weight with respect to a total weight of the composite resin (A) and the photo initiator (B).
12. An ultraviolet-curable coating which contains the ultraviolet-curable resin composition described in any one of claim 1 .
13. A coated article which is obtained by coating the ultraviolet-curable coating medium described in claim 12 .