Curable Resin Composition, Surface Protection Method, Temporary Fixation Method, and Separation Method

Abstract

To provide an environmentally-friendly curable resin composition for surface protection, having a high adhesive strength and being capable of forming a protective film which will readily be removed in the film form without adhesive residue in water on a member to be processed, a photocurable adhesive using it, a method for temporarily fixing a member, and a method for removing a protective film. A curable resin composition for surface protection, comprising (A) a polyfunctional (meth)acrylate, (B) a monofunctional (meth)acrylate, and (C) a resin having a cyclopentadiene skeleton. Further, a curable resin composition for surface protection, comprising (A) a polyfunctional (meth)acrylate, (B) a monofunctional (meth)acrylate, (C) a resin having a cyclopentadiene skeleton, and (D) a photopolymerization initiator. Still further, a curable resin composition for surface protection, comprising (A) a polyfunctional (meth)acrylate, (B) a monofunctional (meth)acrylate, (C) a resin having a cyclopentadiene skeleton, (D) a photopolymerization initiator, and (E) a polar organic solvent.

1 . A curable resin composition for surface protection, comprising (A) a polyfunctional (meth)acrylate, (B) a monofunctional (meth)acrylate, and (C) a resin having a cyclopentadiene skeleton. 
   
   
       2 . The curable resin composition according to  claim 1 , further comprising (D) a photopolymerization initiator. 
   
   
       3 . The curable resin composition according to  claim 2 , further comprising (E) a polar organic solvent. 
   
   
       4 . The curable resin composition for surface protection according to  claim 1 , wherein (C) has an ester group or a hydroxyl group in its molecule. 
   
   
       5 . A curable resin composition for surface protection, comprising (F) a (meth)acrylate having at least one (meth)acryloyl group at the terminal or in the side chain of its molecule and having a molecular weight of at least 500, (G) a (meth)acrylate other than (F), and (D) a photopolymerization initiator. 
   
   
       6 . The curable resin composition for surface protection according to  claim 5 , wherein (F) is at least one member selected from the group consisting of polybutadiene, polyisoprene, and a hydrogenated product of polybutadiene or polyisoprene. 
   
   
       7 . The curable resin composition for surface protection according to  claim 5 , further comprising (H) an inorganic filler. 
   
   
       8 . The curable resin composition for surface protection according to  claim 7 , wherein (H) is silica. 
   
   
       9 . The curable resin composition for surface protection according to  claim 5 , wherein each of (A), (B), (F) and (G) is a hydrophobic (meth)acrylate. 
   
   
       10 . The curable resin composition for surface protection according to  claim 1 , which comprises from 1 to 50 parts by mass of (A), from 5 to 95 parts by mass of (B), and from 0.1 to 50 parts by mass of (C). 
   
   
       11 . The curable resin composition for surface protection according to  claim 2 , which comprises from 1 to 50 parts by mass of (A), from 5 to 95 parts by mass of (B), from 0.1 to 50 parts by mass of (C), and from 0.1 to 20 parts by mass of (D). 
   
   
       12 . The curable resin composition for surface protection according to  claim 3 , which comprises from 1 to 50 parts by mass of (A), from 5 to 95 parts by mass of (B), from 0.1 to 50 parts by mass of (C), from 0.1 to 20 parts by mass of (D), and from 0.5 to 10 parts by mass of (E). 
   
   
       13 . The curable resin composition for surface protection according to  claim 5 , which comprises from 20 to 90 parts by mass of (F), from 10 to 80 parts by mass of (G), and from 0.1 to 20 parts by mass of (D). 
   
   
       14 . An adhesive comprising the curable resin composition for surface protection as defined in  claim 1 . 
   
   
       15 . A member to be processed, comprising a cured product of the curable resin composition for surface protection, as defined in  claim 1 , provided on its surface. 
   
   
       16 . A method for protecting the surface of a member to be processed, which comprises providing a protective film made of a cured product of the curable resin composition for surface protection as defined in  claim 1  on the surface of the member to be processed, processing the member to be processed, and removing the protective film from the member to be processed. 
   
   
       17 . A method for temporarily fixing a member to be processed, which comprises bonding the member to be processed to a substrate by means of the curable resin composition for surface protection as defined in  claim 1 , curing the composition, processing the member to be processed, and immersing the processed member in warm water of at most 90° C., thereby to remove a cured product of the curable resin composition for surface protection. 
   
   
       18 . A method for removing a protective film, which comprises providing a protective film made of the curable resin composition for surface protection as defined in  claim 1  on the surface of a member to be processed, processing the member to be processed, and removing the protective film from the member to be processed, wherein a sheet is bonded to the surface of the member to be processed and/or the protective film, and the member to be processed is separated from the protective film and the sheet, or the protective film is separated from the member to be processed and the sheet.