Adhesive composition, optical member, and surface protective sheet

Abstract

An adhesive composition includes a copolymer (A), the copolymer (A) being a copolymer of: a hydroxyl group-containing (meth)acrylamide (a1), the hydroxyl group-containing (meth)acrylamide (a1) including at least one of a hydroxyl group-containing acrylamide and a hydroxyl group-containing methacrylamide, and a (meth)acrylate (a2), the (meth)acrylate (a2) including at least one of an acrylic ester and a methacrylic ester; and an antistatic agent (B), the antistatic agent (B) including an ionic compound.

1 - 21 . (canceled) 
     
     
         22 . An optical member, comprising:
 an optical sheet; and   an adhesive layer formed on one or both sides of the optical sheet from an adhesive composition that includes:   a copolymer (A), the copolymer (A) being a copolymer of:
 a hydroxyl group-containing (meth)acrylamide (a1), the hydroxyl group-containing (meth)acrylamide (a1) including at least one of a hydroxyl group-containing acrylamide and a hydroxyl group-containing methacrylamide, and 
 a (meth)acrylate (a2), the (meth)acrylate (a2) including at least one of an acrylic ester and a methacrylic ester; 
   an antistatic agent (B), the antistatic agent (B) including an ionic compound; and   a crosslinking agent,   wherein the adhesive layer has a gel fraction, at 3 days at 23° C. under a relative humidity of 50%, of about 50 to about 80% as a crosslinking degree.   
     
     
         23 . The optical member as claimed in  claim 22 , wherein the hydroxyl group-containing (meth)acrylamide (a1) is represented by the following formula:
 H 2 C═C(R1)ACONHCH 2 CH 2 OH, in which:   R1 is H or CH 3 ,   A is a linking group, the linking group being (COOCH 2 CH 2 ) n , COOCH 2 CH 2 OOC—CH 2 CH 2 , a single bond, or Compound 1 represented by Chemical Formula 1:   
       
         
           
           
               
               
           
         
       
       and
 n is 1 or 2. 
 
     
     
         24 . The optical member as claimed in  claim 22 , wherein the copolymer (A) includes about 0.1 to about 5% by weight of the hydroxyl group-containing (meth)acrylamide (a1) based on a total weight of the copolymer (A). 
     
     
         25 . The optical member as claimed in  claim 22 , wherein the copolymer (A) includes about 50 to about 99.1% by weight of the (meth)acrylate (a2) based on a total weight of the copolymer (A). 
     
     
         26 . The optical member as claimed in  claim 22 , wherein the (meth)acrylate (a2) includes at least one of methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, isobutyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-dodecyl (meth)acrylate, n-tridecyl (meth)acrylate, n-tetradecyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, cyclohexyl (meth)acrylate, t-butylcyclohexyl (meth)acrylate, phenoxyethyl (meth)acrylate, nonylphenoxy polyethylene glycol (meth)acrylate, benzyl (meth)acrylate, isobornyl (meth)acrylate, and tetrahydrofurfuryl (meth)acrylate. 
     
     
         27 . The optical member as claimed in  claim 22 , wherein the copolymer (A) includes about 80 to about 99.89% by weight of n-butyl acrylate as the (meth)acrylate (a2) based on a total weight of the copolymer (A). 
     
     
         28 . The optical member as claimed in  claim 22 , wherein the copolymer (A) includes about 0.1 to about 5% by weight of hydroxyethylacrylamide as the hydroxyl group-containing (meth)acrylamide (a1) based on a total weight of the copolymer (A). 
     
     
         29 . The optical member as claimed in  claim 22 , wherein the copolymer (A) has a polystyrene conversion weight-average molecular weight of about 1,000,000 to about 2,000,000 as determined by gel permeation chromatography. 
     
     
         30 . The optical member as claimed in  claim 22 , wherein the copolymer (A) has a glass transition temperature (Tg) of about 0° C. or less. 
     
     
         31 . The optical member as claimed in  claim 22 , wherein the ionic compound includes at least one of an imidazolium salt, a pyridinium salt, an alkyl ammonium salt, an alkyl pyrrolidium salt, and an alkyl phosphonium salt. 
     
     
         32 . The optical member as claimed in  claim 22 , wherein the copolymer (A) is crosslinked. 
     
     
         33 . The optical member as claimed in  claim 22 , wherein the gel fraction has a stabilizing period of about 3 days or less. 
     
     
         34 . The optical member as claimed in  claim 22 , wherein the adhesive composition includes about 0.01 to about 2.0% by weight of the antistatic agent (B). 
     
     
         35 . The optical member as claimed in  claim 22 , wherein the adhesive layer has a sheet resistance of about 1×10 8  to about 1×10 11  Ω/cm 2 . 
     
     
         36 . A surface protection sheet, comprising:
 a protective film; and   an adhesive layer formed on one or both sides of the protective film from an adhesive composition that includes:   a copolymer (A), the copolymer (A) being a copolymer of:
 a hydroxyl group-containing (meth)acrylamide (a1), the hydroxyl group-containing (meth)acrylamide (a1) including at least one of a hydroxyl group-containing acrylamide and a hydroxyl group-containing methacrylamide, and 
 a (meth)acrylate (a2), the (meth)acrylate (a2) including at least one of an acrylic ester and a methacrylic ester; 
   an antistatic agent (B), the antistatic agent (B) including an ionic compound; and   a crosslinking agent,   wherein the adhesive layer has a gel fraction, at 3 days at 23° C. under a relative humidity of 50%, of about 90 to about 100% as a crosslinking degree.   
     
     
         37 . The surface protection sheet as claimed in  claim 36 , wherein the hydroxyl group-containing (meth)acrylamide (a1) is represented by the following formula: H 2 C═C(R1)ACONHCH 2 CH 2 OH, in which:
 R1 is H or CH 3 , 
 A is a linking group, the linking group being (COOCH 2 CH 2 ) n , COOCH 2 CH 2 OOC—CH 2 CH 2 , a single bond, or Compound 1 represented by Chemical Formula 1: 
 
       
         
           
           
               
               
           
         
       
       and
 n is 1 or 2. 
 
     
     
         38 . The surface protection sheet as claimed in  claim 36 , wherein the copolymer (A) includes about 0.1 to about 10% by weight of the hydroxyl group-containing (meth)acrylamide (a1) based on a total weight of the copolymer (A). 
     
     
         39 . The surface protection sheet as claimed in  claim 36 , wherein the copolymer (A) includes about 50 to about 99.1% by weight of the (meth)acrylate (a2) based on a total weight of the copolymer (A). 
     
     
         40 . The surface protection sheet as claimed in  claim 36 , wherein the (meth)acrylate (a2) includes at least one of methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, isobutyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-dodecyl (meth)acrylate, n-tridecyl (meth)acrylate, n-tetradecyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, cyclohexyl (meth)acrylate, t-butylcyclohexyl (meth)acrylate, phenoxyethyl (meth)acrylate, nonylphenoxy polyethylene glycol (meth)acrylate, benzyl (meth)acrylate, isobornyl (meth)acrylate, and tetrahydrofurfuryl (meth)acrylate. 
     
     
         41 . The surface protection sheet as claimed in  claim 36 , wherein the copolymer (A) includes about 50 to about 99.89% by weight of 2-ethylhexylacrylate as the (meth)acrylate (a2) based on a total weight of the copolymer (A). 
     
     
         42 . The surface protection sheet as claimed in  claim 36 , wherein the copolymer (A) has a polystyrene conversion weight-average molecular weight of about 300,000 to about 1,000,000 as determined by gel permeation chromatography. 
     
     
         43 . The surface protection sheet as claimed in  claim 36 , wherein the copolymer (A) has a glass transition temperature (Tg) of about 0° C. or less. 
     
     
         44 . The surface protection sheet as claimed in  claim 36 , wherein the ionic compound includes at least one of an imidazolium salt, a pyridinium salt, an alkyl ammonium salt, an alkyl pyrrolidium salt, and an alkyl phosphonium salt. 
     
     
         45 . The surface protection sheet as claimed in  claim 36 , wherein the copolymer (A) is crosslinked. 
     
     
         46 . The surface protection sheet as claimed in  claim 36 , wherein the adhesive composition includes about 0.01 to about 2.0% by weight of the antistatic agent (B). 
     
     
         47 . The surface protection sheet as claimed in  claim 36 , wherein the adhesive layer has a sheet resistance of about 1×10 8  to about 1×10 11  Ω/cm 2 . 
     
     
         48 . The surface protection sheet as claimed in  claim 36 , wherein the gel fraction has a stabilizing period of about 3 days or less.