Transparent multilayer film containing poly(meth)acrylimide-based resin layer, and method for producing said transparent multilayer film

Patent metadata

Field	Value
Publication number	US-10112369-B2
Application number	US-201415022889-A
Country	US
Kind code	B2
Filing date	Jul 4, 2014
Priority date	Sep 20, 2013
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

Embodiments of the invention provide a transparent poly(meth)acrylimide-based resin multilayer film exhibiting excellent surface smoothness, transparency, outer appearance, and resistance to puchability. According to at least one embodiment, there is provided a method for producing said transparent multilayer film, in which the transparent multilayer film in which a first poly(meth)acrylimide-based resin layer (α1), an aromatic polycarbonate-based resin layer (β), and a second poly(meth)acrylimide-based resin layer (α2) are directly laminated in said order, and in that the total light transmittance exceeds 90% and the haze is 2.0% or lower. The transparent multilayer film is produced by continuously coextruding, from a T die, a molten film of the transparent multilayer film in which the aforementioned layers were directly laminated in the aforementioned order, and by supplying and then pressing the molten film between a first mirror body that has a surface temperature between 100 and 200° C. and a second mirror body that has a surface temperature between 20 and 200° C.

First claim

The invention claimed is:

1. A transparent multilayer film, comprising:
a first poly(meth)acrylimide resin layer (α1);
an aromatic polycarbonate resin layer ((β); and
a second poly(meth)acrylimide resin layer (α2), the layers being laminated directly in this order,
wherein the transparent multilayer film satisfies the following requirements (i), (ii) and (iii):
(i) a total light transmittance of higher than 90%;
(ii) (ii) a haze of 2.0% or lower; and
(iii) a retardation of 50 nm or lower.

2. A hard coat-laminated film, comprising a transparent multilayer film according to claim 1 , and a hard coat formed on at least one surface the transparent multilayer film.

3. An image display apparatus member, comprising a film according to claim 1 .

4. A method for producing a transparent multilayer film, comprising the steps of:
continuously coextruding, with a coextrusion apparatus equipped with an extruder and a T die, a molten film of a transparent multilayer film from the T die, wherein the transparent multilayer film has a first poly(meth)acrylimide resin layer (α1), an aromatic polycarbonate resin layer (β), and a second poly(meth)acrylimide resin layer (α2), the layers being laminated directly in this order;
feeding and pressing the molten film of the transparent multilayer film between a first rotating or circulating mirror-finished body and a second rotating or circulating mirror-finished body; and
delivering the molten film to a following transfer roll while making the molten film to be held on the first rotating or circulating mirror-finished body,
wherein the first rotating or circulating mirror-finished body has a surface temperature of 100° C. or higher and 200° C. or lower, the second rotating or circulating mirror-finished body has a surface temperature of 20° C. or higher and less than 200° C., and the surface temperature of the first rotating or circulating mirror-finished body is higher than the surface temperature of the second rotating or circulating mirror-finished body.

5. A method for producing a hard coat-laminated film, comprising the steps of:
(1) producing a transparent multilayer film by a method according to claims 4 ; and
(2) forming a hard coat on at least one surface of the transparent multilayer film obtained in the step (1).

6. A transparent multilayer film according to claim 1 , wherein the transparent multilayer film has a retardation of 12 nm or lower.

7. A method according to claim 4 , wherein the surface temperature of the first mirror-finished body is 10 to 90° C. higher than the surface temperature of the second mirror-finished body.

8. A method according to claim 4 , wherein the surface temperature of the first mirror-finished body ranges from 120 to 200° C.; and the surface temperature of the second mirror-finished body ranges from 20° C. or higher and less than 200° C.

9. A method for producing an image display apparatus, which comprises incorporating a film obtained by the method according to any one of claim 4 , 5 , or 7 into the image display apparatus as a member of the image display apparatus.

Assignees

• Riken Technos Corp

Inventors

• Nakashima Kohei
• NEGIMOTO Shintaro

Classifications

• B32B2307/554

  Wear resistance · CPC title

• B29C48/0011

  combined with compression moulding · CPC title

• B32B27/365

  comprising polycarbonates · CPC title

• B32B2307/412

  Transparent · CPC title

• B32B2379/08

  Polyimides · CPC title