Laminate

Patent metadata

Field	Value
Publication number	US-9429685-B2
Application number	US-201113697157-A
Country	US
Kind code	B2
Filing date	Apr 6, 2011
Priority date	May 25, 2010
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

The laminate of an embodiment is a laminate including an antireflection film and a protection film bonded onto the antireflection film, wherein the surface of the antireflection film includes a plurality of protrusions; the protection film includes a supporting film and an adhesive layer; the adhesive layer includes an adhesive agent, a copolymer, and a carboxyl group-containing monomer; the weight average molecular weight of the copolymer is 1000000 or more and 2000000 or less; the copolymer includes the (meth)acrylic acid alkyl ester with the alkyl group having 4 or less carbon atoms in the largest weight proportion among the monomer components; the acid number of the copolymer is 16 mg KOH/g or more and 120 mg KOH/g or less; and the mixing amount of the epoxy cross-linking agent in relation to 100 parts by weight of the copolymer is 1.5 parts by weight or more.

First claim

The invention claimed is:

1. A laminate comprising:
an antireflection film and a protection film bonded onto the antireflection film,
wherein a surface of the antireflection film comprises a plurality of protrusions wherein a width between the tops of adjacent protrusions is equal to or less than a wavelength of visible light;
the protection film comprises a supporting film and an adhesive layer in contact with the antireflection film;
the adhesive layer is constituted with an adhesive agent that has a gel fraction of 95% or more and is prepared by cross-linking with an epoxy cross-linking agent a copolymer obtained by polymerizing monomer components comprising as essential components a (meth)acrylic acid alkyl ester with the alkyl group having 4 or less carbon atoms, and a carboxyl group-containing monomer;
the monomer components including at least one of methyl (meth)acrylate and butyl (meth)acrylate as the (meth)acrylic acid alkyl ester and (meth)acrylic acid as the carboxyl group-containing monomer;
the weight average molecular weight of the copolymer is 1000000 or more and 2000000 or less;
the copolymer comprises the (meth)acrylic acid alkyl ester with the alkyl group having 4 or less carbon atoms in the largest weight proportion among the monomer components,
the acid number of the copolymer is 16 mg KOH/g or more and 46 mg KOH/g or less; and
the mixing amount of the epoxy cross-linking agent in relation to 100 parts by weight of the copolymer is 1.5 parts by weight or more and 5 parts by weight or less.

2. The laminate according to claim 1 , wherein the (meth)acrylic acid alkyl ester with the alkyl group having 1 to 4 carbon atoms accounts for a proportion of 60% by weight or more in relation to the whole monomers constituting the monomer components.

3. The laminate according to claim 1 , wherein the carboxyl group-containing monomer is a (meth)acrylic acid or a carboxyethyl (meth)acrylate.

4. The laminate according to claim 1 , wherein the monomer components do not comprise a monomer having a hydroxyl group, an amino group or an amide group, or comprise a monomer having a hydroxyl group, an amino group or an amide group and the concentration of the monomer having a hydroxyl group, an amino group or an amide group in relation to the whole monomer components is 0.5% by weight or less.

5. The laminate according to claim 1 wherein the molecular weight distribution of the copolymer falls within a range of 2 or more and 8 or less.

6. The laminate according to claim 1 , wherein the glass transition temperature of the copolymer falls within a range of −50° C. or higher and 0° C. or lower.

7. The laminate according to claim 1 , wherein the copolymer is a copolymer synthesized by solution polymerization.

8. The laminate according to claim 1 , wherein the gaps between the plurality of protrusions of the antireflection film each have a shape sharpened toward the inside of the antireflection film.

Assignees

• Minoura Kiyoshi
• Imaoku Takao
• Taguchi Tokio
• Shimizu Seiichi
• Ooka Ryuta
• Sharp Kk
• Soken Kagaku Kk

Inventors

• Minoura Kiyoshi
• Imaoku Takao
• Taguchi Tokio
• Shimizu Seiichi
• Ooka Ryuta

Classifications

• B32B2551/00

  Optical elements · CPC title

• B32B27/36

  comprising polyesters · CPC title

• B32B2367/00

  Polyesters, e.g. PET, i.e. polyethylene terephthalate · CPC title

• C09J2433/00

  Presence of (meth)acrylic polymer · CPC title

• C09J7/026

  Chemistry & Metallurgy · mapped topic