Multilayer film, laminate, airbag, and method of manufacturing laminate

Patent metadata

Field	Value
Publication number	US-11072152-B2
Application number	US-201916710458-A
Country	US
Kind code	B2
Filing date	Dec 11, 2019
Priority date	Jun 16, 2017
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

A multilayer film, which is used upon being adhered to a fabric, includes an adhesive layer to be a side of the multilayer film to be adhered to the fabric, the adhesive layer including a thermoplastic polyester elastomer and a polymer having a Shore D hardness of less than 80; and a barrier layer bonded to the adhesive layer, the barrier layer including a thermoplastic elastomer.

First claim

What is claimed is:

1. An airbag comprising:
a fabric formed to have a shape of a bag; and
a multilayer film including
an adhesive layer that includes a thermoplastic polyester elastomer and a polymer having a Shore D hardness of less than 80, the adhesive layer including at least a first layer and a second layer of different compositions; and
a barrier layer bonded to the adhesive layer, the barrier layer including a thermoplastic polyester elastomer, and having a melting point equal to or greater than 180° C., wherein
the fabric is adhered to the first layer of the adhesive layer;
the barrier layer is adhered to the second layer of the adhesive layer;
at least one layer of the first layer or the second layer includes the polymer having the Shore D hardness of less than 80; and
a content ratio of a soft segment in the thermoplastic polyester elastomer included in the barrier layer is 5% by weight to 60% by weight with respect to 100% by weight of the thermoplastic polyester elastomer included in the barrier layer.

2. The airbag according to claim 1 , wherein the polymer having the Shore D hardness of less than 80 includes one or more types selected from the group consisting of ethylene-vinyl acetate copolymer, polyethylene, a hydrogenated styrene thermoplastic elastomer, and an ethylene-butyl acrylate copolymer.

3. The airbag according to claim 1 , wherein
the melting point of the barrier layer is higher than a melting point of the adhesive layer.

4. The airbag according to claim 1 , wherein
the thermoplastic polyester elastomer included in the adhesive layer includes a soft segment including polyether and a hard segment including polyester.

5. The airbag according to claim 1 , wherein
a ratio value of a content ratio of a soft segment in the thermoplastic polyester elastomer in the adhesive layer with respect to a content ratio of a soft segment in the thermoplastic polyester elastomer in the barrier layer, is 5 or less.

6. The airbag according to claim 1 , wherein
a ratio value of a content ratio of a soft segment in the thermoplastic polyester elastomer in the adhesive layer with respect to a content ratio of a soft segment in the thermoplastic polyester elastomer in the barrier layer, is 1.2 or more.

7. The airbag according to claim 1 , wherein
a ratio value of a content ratio of a soft segment in the thermoplastic polyester elastomer in the adhesive layer with respect to a content ratio of a soft segment in the thermoplastic polyester elastomer in the barrier layer, is 1.2 to 5.

8. The airbag according to claim 1 , wherein
a content ratio of the polymer having the Shore D hardness of less than 80 in the adhesive layer, is 1% by weight to 60% by weight.

9. The airbag according to claim 1 , wherein
a content ratio of a soft segment in the thermoplastic polyester elastomer included in the adhesive layer is 50% by weight to 90% by weight with respect to 100% by weight of the thermoplastic polyester elastomer included in the adhesive layer.

10. The airbag according to claim 1 , wherein
the first layer of the adhesive layer includes the thermoplastic polyester elastomer and the polymer having the Shore D hardness of less than 80, and
the second layer of the adhesive layer includes the thermoplastic polyester elastomer.

11. The airbag according to claim 1 , wherein
the fabric includes polyester.

12. The airbag according to claim 1 , wherein
the adhesive layer includes 30 wt % to 60 wt % of the polymer having the Shore D hardness of less than 80.

13. The airbag according to claim 1 , wherein
a content ratio of the polymer having the Shore D hardness of less than 80 in the first adhesive layer is 1% by weight to 60% by weight.

14. The airbag according to claim 1 , wherein
the first adhesive layer includes the polymer having the Shore D hardness of less than 80, and
the polymer having the Shore D hardness of less than 80 is one or more polymers selected from the group consisting of an ethylene-vinyl acetate copolymer, polyethylene, a hydrogenated styrene thermoplastic elastomer, and an ethylene-butyl acrylate copolymer.

15. The airbag according to claim 1 , wherein
a second adhesive layer of the two or more adhesive layers is provided on a side of the multilayer film that is adhered to the barrier layer,
the polymer having the Shore D hardness of less than 80 is provided in one of either the first adhesive layer or the second adhesive layer, and
the polymer having the Shore D hardness of less than 80 is an ethylene-vinyl acetate copolymer.

16. The airbag according to claim 1 , wherein
the first adhesive layer includes the polymer having the Shore D hardness of less than 80, and
the polymer having the Shore D hardness of less than 80 is polyethylene.

Assignees

• Nitto Denko Corp
• Nitto Switzerland Ag

Inventors

• Yamada Yosuke
• Tagami Toru
• Ludwig Michael

Classifications

• B32B2307/714

  Inert, i.e. inert to chemical degradation, corrosion · CPC title

• B32B37/1207

  Heat-activated adhesive (B32B37/04 takes precedence) · CPC title

• B32B2307/308

  Heat stability · CPC title

• B32B2262/04

  Cellulosic plastic fibres, e.g. rayon · CPC title

• B32B27/32

  comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} · CPC title