Sealing assembly for a solid polymer ion exchange membrane

• US 5,945,192 A
• Filed: 11/04/1997
• Issued: 08/31/1999
• Est. Priority Date: 06/29/1995
• Status: Expired due to Term

• Current Assignee: Japan Gore-Tex Inc
• Original Assignee: Japan Gore-Tex Inc
• Inventors: Kato, Hiroshi, Torikai, Eiichi
• Primary Examiner(s): Chen, Vivian
• Application Number:
  US08/963,727
• Time in Patent Office: 665 Days
• Field of Search: 428/77, 428/78, 428/81, 428/79, 428/195, 428/198, 428/201, 428/304.4, 428/305.5, 428/306.6, 428/308.4, 428/310.5, 428/317.1, 428/317.3, 428/318.4 , 428/319.3, 428/421, 428/422, 204/518, 204/520, 204/527, 204/536, 204/630, 204/632, 204/633, 277/945, 277/946
• US Class Current: 428/77
• CPC Class Codes: B01D 61/52 Accessories; Auxiliary operation
• CPC Class Codes: B01D 65/003 Membrane bonding or sealing
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: C25B 13/00 Diaphragms; Spacing elements
• CPC Class Codes: C25B 13/08 based on organic materials
• CPC Class Codes: H01M 8/0271 Sealing or supporting means around electrodes, matrices or membranes
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10S 277/945 Containing fluorine
• CPC Class Codes: Y10S 277/946 PTFE
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]
• CPC Class Codes: Y10T 428/24826 Spot bonds connect components
• CPC Class Codes: Y10T 428/24851 Intermediate layer is discontinuous or differential
• CPC Class Codes: Y10T 428/249953 Composite having voids in a component [e.g., porous, cellular, etc.]
• CPC Class Codes: Y10T 428/249954 With chemically effective material or specified gas other than air, N, or carbon dioxide in void-containing component
• CPC Class Codes: Y10T 428/249955 Void-containing component partially impregnated with adjacent component
• CPC Class Codes: Y10T 428/249958 Void-containing component is synthetic resin or natural rubbers
• CPC Class Codes: Y10T 428/249961 With gradual property change within a component
• CPC Class Codes: Y10T 428/249982 With component specified as adhesive or bonding agent
• CPC Class Codes: Y10T 428/249983 As outermost component
• CPC Class Codes: Y10T 428/249987 : With nonvoid component of specified composition
• CPC Class Codes: Y10T 428/249991 : Synthetic resin or natural rubbers
• CPC Class Codes: Y10T 428/3154 : Of fluorinated addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31544 : Addition polymer is perhalogenated

Abstract

An assembly consisting of at least one seal layer and a solid polymer ion exchange layer wherein the seal layer covers essentially only the region of the ion exchange layer which is to be sealed. The seal layer is made of porous polytetrafluoroethylene film having one surface coated and partially impregnated with a solid polymer ion exchange material. The seal layer provides support and masking functions for the solid polymer ion exchange layer during intermediate manufacturing steps, and reinforcement and effective sealing when assembled in an electrochemical apparatus.

Claims

1. A unitary assembly for use in an electrochemical apparatus, said assembly comprising:

an ion exchange layer comprising a fluorine-containing solid polymer electrolyte membrane, said ion exchange layer having opposite facing planar surfaces;

at least one said planar surface having thereon a seal layer, said seal layer disposed so as to cover and adhere to essentially only the region to be sealed of said ion exchange layer;

said seal layer comprising a porous polytetrafluoroethylene film containing an amount of said solid polymer electrolyte, said seal layer also having opposite facing planar surfaces;

a portion of said solid polymer electrolyte disposed on the planar surface of said polytetrafluoroethylene film contiguous with said ion exchange layer, and a portion of said solid polymer electrolyte penetrating into, but not through, said porous polytetrafluoroethylene film so that the opposite facing surface of said porous polytetrafluoroethylene film is free of solid polymer electrolyte;

said ion exchange layer and said seal layer bonded at their adjoining surfaces by said solid polymer electrolyte.

2. The assembly as recited in claim 1 wherein the solid polymer electrolyte of the seal layer is disposed continuously to form a non-porous film completely covering said surface of the seal layer contiguous with said ion exchange layer.

3. The assembly as recited in claim 2 wherein the porous polytetrafluoroethylene film of the seal layer is a porous expanded polytetrafluoroethylene film.

4. The assembly as recited in claim 1 wherein the solid polymer electrolyte of the seal layer is disposed noncontinuously, in spots or lines, over the entirety of said surface of the seal layer contiguous with said ion exchange layer.

5. The assembly as recited in claim 4 wherein the porous polytetrafluoroethylene film of the seal layer is a porous expanded polytetrafluoroethylene film.

6. The assembly as recited in claim 1 wherein the porous polytetrafluoroethylene film of the seal layer is a porous expanded polytetrafluoroethylene film.