Microporous waterproof and moisture vapor permeable structures, processes of manufacture and useful articles thereof

• US 5,066,683 A
• Filed: 05/01/1990
• Issued: 11/19/1991
• Est. Priority Date: 01/05/1987
• Status: Expired due to Term

• Current Assignee: Donaldson Company Incorporated
• Original Assignee: Tetratec Corporation
• Inventors: Dillon, Mark E., Dillon, Joseph E.
• Primary Examiner(s): Foelak, Morton
• Application Number:
  US07/518,435
• Time in Patent Office: 567 Days
• Field of Search: 55/16, 55/158, 521/54, 521/55, 521/134, 521/154, 521/145, 525/104, 524/427
• US Class Current: 521/54
• CPC Class Codes: B29C 48/022 characterised by the choice of material
• CPC Class Codes: B29C 48/08 flexible, e.g. films
• CPC Class Codes: B29K 2027/18 PTFE, i.e. polytetrafluorethene , e.g. ePTFE, i.e. expanded polytetrafluorethene
• CPC Class Codes: C08F 230/08 containing silicon
• CPC Class Codes: C08F 259/08 on to polymers containing fluorine
• CPC Class Codes: C08G 77/04 Polysiloxanes
• CPC Class Codes: C08G 77/80 Siloxanes having aromatic substituents, e.g. phenyl side groups
• CPC Class Codes: C08J 2327/18 Homopolymers or copolymers of tetrafluoroethylene
• CPC Class Codes: C08J 2427/00 Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers
• CPC Class Codes: C08J 2483/00 Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen, or carbon only; Derivatives of such polymers
• CPC Class Codes: C08J 9/365 Coating
• CPC Class Codes: C08J 9/42 with macromolecular compounds
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 2666/14 Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
• CPC Class Codes: C08L 27/18 Homopolymers or copolymers or tetrafluoroethene
• CPC Class Codes: C08L 83/04 Polysiloxanes
• CPC Class Codes: Y10S 525/903 Interpenetrating network

Abstract

Microporous waterproof and moisture vapor permeable products are described which are formed from a matrix having an internal microstructure which is coated with a hydrophobic material. A process is described including the steps of (1) applying to the surface of the matrix a liquid hydrophobic material, (2) allowing the liquid to penetrate into the microstructure and then (3) drying, vulcanizing or curing the product.

Claims

1. A microporous film consisting essentially of a matrix of microporous biaxially fibrillated semi-interpenetrating polymer networks of polytetrafluoroethylene and silicone, said matrix having an internal microstructure consisting of nodes interconnected by fibrils, wherein said internal microstructure is coated with a sufficient amount of a hydrophobic material so as to increase resistance to surfactant activity and wherein the hydrophobic material is selected from the group consisting of cured silicone compositions, non-cured silicone compositions and compositions resulting from the curing of a mixture of a curable silicone composition and a non-curable silicone composition.

2. A microporous film consisting essentially of a matrix of microporous biaxially fibrillated semi-interpenetrating polymer networks of polytetrafluoroethylene and silicone, said matrix having nodes interconnected by fibrils, wherein the internal microstructure is coated with a sufficient amount of a cured silicone composition effective to provide increased optical transparency of the film.