Self-adsorbing foam sheet

Abstract

Provided is a self-adsorbing foam sheet and a self-adsorbing laminated foam sheet which form almost no formaldehyde, have proper self adsorption strengths, and are excellent in smoothness; the self-adsorbing foam sheet being produced by the process comprising shaping foam that is obtained by foaming a resin composition for a self-adsorbing foam sheet, the resin composition comprising 100 parts by mass of a (meth)acrylic acid ester copolymer resin which includes an N-methylol group and whose glass transition temperature is −10° C. or less, and 1 to 20 parts by mass of a carbodiimide crosslinking agent, into a sheet, and after said shaping, carrying out crosslinking reaction on the (meth)acrylic acid ester copolymer resin; the self-adsorbing laminated foam sheet comprising an adsorbing layer consisting of the self-adsorbing foam sheet, and a supporting layer consisting of a base material.

1 . A resin composition for a self-adsorbing foam sheet, the resin composition comprising:
 100 parts by mass of a (meth)acrylic acid ester copolymer resin which includes an N-methylol group, and whose glass transition temperature is −10° C. or less; and   1 to 20 parts by mass of a carbodiimide crosslinking agent.   
     
     
         2 . The resin composition according to  claim 1 , wherein gel fraction of the (meth)acrylic acid ester copolymer resin is 70% or less. 
     
     
         3 . A self-adsorbing foam sheet produced by the process comprising:
 shaping foam that is obtained by foaming the resin composition according to  claim 1 , into a sheet; and   after said shaping, carrying out crosslinking reaction on the (meth)acrylic acid ester copolymer resin.   
     
     
         4 . A self-adsorbing laminated foam sheet comprising:
 an adsorbing layer consisting of the self-adsorbing foam sheet according to  claim 3 ; and   a supporting layer consisting of a base material.   
     
     
         5 . The self-adsorbing laminated foam sheet according to  claim 4 , wherein the base material is a resin film. 
     
     
         6 . A method for producing a self-adsorbing foam sheet, the method comprising:
 making a resin composition for a self-adsorbing foam sheet, the resin composition including: 100 parts by mass of a (meth)acrylic acid ester copolymer resin which includes an N-methylol group, and whose glass transition temperature is −10° C. or less; and 1 to 20 parts by mass of a carbodiimide crosslinking agent;   foaming the resin composition, to obtain foam of the resin composition; and   shaping the foam into a sheet and after that, carrying out crosslinking reaction on the (meth)acrylic acid ester copolymer resin.   
     
     
         7 . The method according to  claim 6 , wherein gel fraction of the (meth)acrylic acid ester copolymer resin is 70% or less. 
     
     
         8 . A method for producing a self-adsorbing laminated foam sheet that includes an adsorbing layer consisting of a self-adsorbing foam sheet and a supporting layer consisting of a base material, the method comprising:
 making a resin composition for a self-adsorbing foam sheet, the resin composition including: 100 parts by mass of a (meth)acrylic acid ester copolymer resin which includes an N-methylol group, and whose glass transition temperature is −10° C. or less; and 1 to 20 parts by mass of a carbodiimide crosslinking agent;   foaming the resin composition, to obtain foam of the resin composition; and   shaping the foam into a sheet on the base material, and after that, carrying out crosslinking reaction on the (meth)acrylic acid ester copolymer resin, to laminate the adsorbing layer to the supporting layer.   
     
     
         9 . The method according to  claim 8 , wherein gel fraction of the (meth)acrylic acid ester copolymer resin is 70% or less. 
     
     
         10 . The method according to  claim 9 , wherein the base material is a resin film.