Process For The Production Of A Structured Film

Patent metadata

Field	Value
Publication number	US-2016167291-A1
Application number	US-201414907668-A
Country	US
Kind code	A1
Filing date	Aug 21, 2014
Priority date	Aug 23, 2013
Publication date	Jun 16, 2016
Grant date	—

Abstract

The present invention relates to a process for the formation of a structured film, a structured film as such, an article comprising the structured film, a device for the continuous formation of such a structured film and a composite comprising the structured film.

First claim

1 . A process for the formation of a structured porous film comprising:
a) applying a porous film onto an elastic substrate in a stretched state such that a reversible adhesion of the porous film on the stretched substrate occurs, and b) relaxing the substrate with the applied film thereon to obtain a structured porous film.

2 . The process according to claim 1 , further comprising applying a backer material to the structured porous film.

3 . The process according to claim 1 , wherein the porous film comprises a member selected from fluoropolymer, a polyvinylalcohol, a polyurethane and combinations thereof.

4 . The process according to claim 3 , wherein the porous film comprises a member selected from polytetrafluoroethylene (PTFE), a modified PTFE, a fluorothermoplastic, fluoroelastomer and combinations thereof.

5 . The process according to claim 1 , wherein the porous film has a thickness of between 0.5 μm and 250 μm.

6 . The process according to claim 1 , wherein the substrate comprises a member selected from a polysiloxane, fluorosilicone rubber and combinations thereof.

7 . The process according to, claim 1 , wherein the substrate is stretched at a processing ratio of at least 110% in at least one direction.

8 . The process according to claim 1 , wherein the elastic substrate is stretched at a processing ratio of at most 1100% in at least one direction.

9 . A structured film obtained by the process according to claim 1 .

10 . The structured film according to claim 9 , wherein structures in the structured film have a height of at least two times the thickness of a non-structured film, and wherein the structure density in at least one direction is at least 1/mm.

11 . A structured porous film comprising a porous film reversibly adhered to an elastic substrate, wherein structures in the porous film have a height at least two times the thickness of a non-structured film and the structure density in at least one direction is at least 1/mm.

12 . The film according to claim 11 , wherein the structure density in at least one direction is at least 2/mm, preferably at least 5 per mm.

13 . The film according to claim 12 , wherein the structure height is from 2 μm to 2000 μm.

14 . The film according to claim 13 , wherein the area increase factor of the structured film is at least 1.8.

15 . An article comprising a structured film according to claim 11 .

16 . The article according to claim 15 , wherein the article is a vent or a filter.

17 . A device for the continuous formation of a structured film according to the process of claim 1 , the device comprising:
a) a moveable elastic substrate belt arranged such that at least a portion of the elastic substrate belt is transformed from a stretched state to a relaxed state during movement of the belt, and b) a means to apply a film onto said elastic substrate belt in the stretched state such that adhesion of the film on the stretched substrate occurs,
wherein the structured film is obtained through the transformation of the elastic belt from the stretched to the relaxed state with the film applied thereto.

18 . A composite comprising a structured film applied to a backer material and having an asymmetric airflow of at least 30%.

Assignees

• Gore W L & Ass Gmbh

Inventors

• Zagl Alexander
• Heller Bernadette
• Hartmann Andre

Classifications

• B29C55/00

  Shaping by stretching, e.g. drawing through a die; Apparatus therefor (B29C61/08 takes precedence) · CPC title

• B29C66/45

  Joining of substantially the whole surface of the articles (methods or apparatus for laminating B32B37/00) · CPC title

• B32B25/08

  of synthetic resin · CPC title

• B32B27/08

  of synthetic resin · CPC title

• B32B2305/026

  Porous · CPC title