Multilayer film, polarization plate, and multilayer film production method

Patent metadata

Field	Value
Publication number	US-2017038510-A1
Application number	US-201415107041-A
Country	US
Kind code	A1
Filing date	Dec 24, 2014
Priority date	Dec 27, 2013
Publication date	Feb 9, 2017
Grant date	—

Abstract

A multilayer film including: an A layer composed of a thermoplastic resin; and a B layer disposed on at least one of the surfaces of the A layer, the B layer being composed of a material Y that contains as a main component a polymer having a glass transition temperature of −50 to 40° C., and a thickness Ta of the A layer, a thickness Tb of the B layer, a planar orientation coefficient P of the A layer, a loss modulus Ea″ of the A layer, a loss modulus Eb″ of the B layer, a storage modulus Ea′ of the A layer, and a storage modulus Eb′ of the B layer satisfying following formulae (1) to (4): (1) 2.5×10 −3 <Tb/Ta<1.0×10 −1 (2) P>1.0×10 −3 (3) Eb″>Ea″+0.01 GPa (4) Eb′<Ea′−1 GPa.

First claim

1 . A multilayer film comprising: an A layer composed of a thermoplastic resin; and a B layer disposed on at least one of the surfaces of the A layer,
the B layer being composed of a material Y that contains as a main component a polymer having a glass transition temperature of −50 to 40° C., and a thickness Ta of the A layer, a thickness Tb of the B layer, a planar orientation coefficient P of the A layer, a loss modulus Ea″ of the A layer, a loss modulus Eb″ of the B layer, a storage modulus Ea′ of the A layer, and a storage modulus Eb′ of the B layer satisfying following formulae (1) to (4):
2.5×10 −3 <Tb/Ta< 1.0×10 −1   (1)

P> 1.0×10 −3   (2)

Eb″>Ea″+ 0.01 GPa  (3)

Eb′<Ea′− 1 GPa.  (4)

2 . The multilayer film according to claim 1 , wherein the thermoplastic resin contains a polymer having an alicyclic structure.

3 . The multilayer film according to claim 1 , wherein the polymer contained in the material Y is a polyurethane.

4 . The multilayer film according to claim 3 , wherein the polyurethane has a carbonate structure in the skeleton structure thereof.

5 . The multilayer film according to claim 1 , wherein the multilayer film has a two-layer structure having only one A layer and only one B layer.

6 . The multilayer film according to claim 1 , wherein the material Y is an aqueous emulsion substantially containing no organic solvent.

7 . A polarization plate comprising: the multilayer film according to claim 1 , and a polarizer film that contains a polyvinyl alcohol.

8 . The polarization plate according to claim 7 , wherein the polarizer film, the B layer, and the A layer are disposed in this order.

9 . A method for producing a multilayer film, the method comprising:
a step of forming a layer 2 with a material Y on a surface of a layer 1 composed of a thermoplastic resin, the material Y containing as a main component a polymer having a glass transition temperature of −50 to 40° C., to thereby form a multilayer film substrate; and a stretching step of stretching the multilayer film substrate to form a multilayer film that includes an A layer that is the layer 1 after stretching and a B layer that is the layer 2 after stretching, a thickness Ta of the A layer, a thickness Tb of the B layer, a planar orientation coefficient P of the A layer, a loss modulus Ea″ of the A layer, and a loss modulus Eb″ of the B layer satisfying, after the stretching step, following formulae (1) to (4):
2.5×10 −3 <Tb/Ta< 1.0×10 −1   (1)

P> 1.0×10 −3   (2)

Eb″>Ea″+ 0.01 GPa  (3)

Eb′<Ea′− 1 GPa.  (4)

10 . A method for producing a multilayer film, the method comprising:
a stretching step of stretching a layer 1 composed of a thermoplastic resin to form an A layer; and a step of forming a B layer with a material Y on a surface of the A layer, the material Y containing as a main component a polymer having a glass transition temperature of −50 to 40° C., a thickness Ta of the A layer, a thickness Tb of the B layer, a planar orientation coefficient P of the A layer, a loss modulus Ea″ of the A layer, and a loss modulus Eb″ of the B layer satisfying following formulae (1) to (4):
2.5×10 −3 <Tb/Ta< 1.0×10 −1   (1)

P> 1.0×10 −3   (2)

Eb″>Ea″+ 0.01 GPa  (3)

Eb′<Ea′− 1 GPa.  (4)

Assignees

• Zeon Corp

Inventors

• Sudeji Hironari

Classifications

• B32B2307/42

  Polarizing, birefringent, filtering · CPC title

• B29C55/023

  using multilayered plates or sheets · CPC title

• B32B2255/10

  on synthetic resin layer or on natural or synthetic rubber layer · CPC title

• G02F2413/01

  Number of plates being 1 · CPC title

• B29D11/0073

  Optical laminates · CPC title