Heat-shrinkable multi-layered film

Patent metadata

Field	Value
Publication number	US-11345126-B2
Application number	US-201917263077-A
Country	US
Kind code	B2
Filing date	Sep 19, 2019
Priority date	Oct 16, 2018
Publication date	May 31, 2022
Grant date	May 31, 2022

Abstract

The present invention aims to provide a heat shrinkable multilayer film capable of providing a heat shrinkable label that can be easily torn along the perforation in both the TD and MD and also has excellent impact resistance and transparency. Provided is a heat shrinkable multilayer film including: front and back layers; an interlayer; and adhesive layers, wherein the front and back layers and the interlayer are stacked with the adhesive layers interposed therebetween, the front and back layers each contain a polyester resin, and the interlayer contains a polystyrene resin in an amount of 80 to 99% by weight and a polyester resin in an amount of 1 to 20% by weight.

First claim

The invention claimed is:

1. A heat shrinkable multilayer film comprising:
front and back layers;
an interlayer; and
adhesive layers,
wherein the front and back layers and the interlayer are stacked with the adhesive layers interposed therebetween,
the front and back layers each contain a polyester resin,
the interlayer contains an aromatic vinyl hydrocarbon-conjugated diene copolymer in an amount of 80 to 99% by weight and a polyester resin in an amount of 1 to 20% by weight,
the aromatic vinyl hydrocarbon-conjugated diene copolymer in the interlayer represents all of a styrene-containing polymer in the interlayer, and
the aromatic vinyl hydrocarbon-conjugated diene copolymer constituting the interlayer is a mixed resin of 50 to 99% by weight of an aromatic vinyl hydrocarbon-conjugated diene copolymer having a Vicat softening temperature of lower than 80° C. and 1 to 50% by weight of an aromatic vinyl hydrocarbon-conjugated diene copolymer having a Vicat softening temperature of 80° C. or higher.

2. The heat shrinkable multilayer film according to claim 1 ,
wherein the adhesive layers each contain a polystyrene resin, a polyester resin, a styrene elastomer, or a polyester elastomer.

3. The heat shrinkable multilayer film according to claim 1 ,
wherein the interlayer further contains a styrene elastomer or a polyester elastomer.

4. The heat shrinkable multilayer film according to claim 1 ,
wherein the polyester resin constituting the interlayer has a glass transition temperature of 30° C. to 95° C.

5. A heat shrinkable label comprising
the heat shrinkable multilayer film according to claim 1 .

Assignees

• Gunze Kk

Inventors

• Onishi Yusuke

Classifications

• B32B27/302

  comprising aromatic vinyl (co)polymers, e.g. styrenic (co)polymers · CPC title

• C09J167/00

  Adhesives based on polyesters obtained by reactions forming a carboxylic ester link in the main chain (based on polyester-amides C09J177/12; based on polyester-imides C09J179/08); Adhesives based on derivatives of such polymers · CPC title

• B32B2307/514

  Oriented · CPC title

• B32B2307/736

  Shrinkable · CPC title

• B32B2519/00

  Labels, badges · CPC title