Coating agent, coating film, laminate and surface-protected article

Abstract

Provided is a coating agent that can be formed into a surface layer having excellent self-restoring properties and stain-proof properties by applying the coating agent onto a surface of a base material (for example, thermoplastic polyurethane) and curing the resulting material. The coating agent according to the present application contains urethane (meth)acrylate-based resin (a), fluorine-based compound (b) and photopolymerization initiator (d). Urethane (meth)acrylate-based resin (a) has weight average molecular weight (Mw) of 10,000 to 800,000. Fluorine-based compound (b) has at least two polymerizable functional groups. The surface layer formed of the coating agent has excellent self-restoring properties of a scratch, stain-proof properties and stretchability.

What is claimed is: 
     
         1 . A coating agent, comprising urethane (meth)acrylate-based resin (a), fluorine-based compound (b) and photopolymerization initiator (d),
 wherein the urethane (meth)acrylate-based resin (a) has weight average molecular weight of 50,000 to 500,000,   the fluorine-based compound (b) has at least two polymerizable functional groups, and   the coating agent contains 1 to 9% by weight of the fluorine-based compound (b) based on a total amount of the urethane (meth)acrylate-based resin (a) and the fluorine-based compound (b).   
     
     
         2 . The coating agent according to  claim 1 , wherein the fluorine-based compound (b) is perfluoropolyether having a (meth)acryloyl group. 
     
     
         3 . The coating agent according to  claim 1 , further comprising fluorosilsesquioxane derivative (c),
 wherein the fluorosilsesquioxane derivative (c) has at least one polymerizable functional group.   
     
     
         4 . The coating agent according to  claim 3 , wherein the fluorosilsesquioxane derivative (c) is cage structure fluorosilsesquioxane. 
     
     
         5 . The coating agent according to  claim 3 , wherein the coating agent contains 0.1 to 10% by weight of the fluorosilsesquioxane derivative (c) based on a total amount of the urethane (meth)acrylate-based resin (a), the fluorine-based compound (b) and the fluorosilsesquioxane derivative (c). 
     
     
         6 . A coating film, obtained by curing the coating agent according to  claim 1 . 
     
     
         7 . A laminate, comprising:
 a base material film formed of thermoplastic polyurethane; and   a surface layer formed by curing the coating agent according to  claim 1  on a first surface side of the base material film.   
     
     
         8 . The laminate according to  claim 7 , comprising:
 an adhesive layer on a side opposite to the first surface side of the base material film; and   a release film on a surface opposite to the base material film of the adhesive layer,   wherein the adhesive layer is composed of at least one resin selected from an acrylic resin, a urethane-based resin, a rubber-based resin and a silicone-based resin, and at least one release agent selected from a fluorine-based resin, a silicone resin and long-chain-containing carbamate is applied onto a surface of the release film relative to the adhesive layer.   
     
     
         9 . A surface-protected article, comprising:
 the laminate according to  claim 8 , from which the release film is peeled off; and   an article prepared by attaching, on a surface thereof, the laminate from which the release film is peeled off, by the adhesive layer.