Patent · US Expired

Release coating for gaskets and manufacturing method

US4635948A · kind A · utility

17Cited by
5References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 18, 1986
Grant dateJan 13, 1987
Priority date
Expiry dateFeb 18, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S277/936
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A soft material, flat gasket having a release coating adhered thereto prepared by a process which includes: perparing a release coating composition which is a suspension including: from 69.5 to 93 parts by weight of an oil having a viscosity in excess of 100 m Pa.times.s and a fire point in excess of 230.degree. C., which oil is one of a mineral oil, a nonreactive silicone oil, and a mixture thereof; from 5 to 20 parts by weight of a polytetrafluoroethylene powder which has a particle size of less than 5.mu.; from 0.5 to 10 parts by weight of an aqueous latex; and from 0.5 to 2 parts by weight of a wetting agent; and applying the release coating composition by coating at least a predetermined portion of at least one surface of the soft material, flat gasket therewith. In spite of the notoriously poor bonding capability of PTFE materials, the release coatings produced in this manner exhibit unexpectedly good adhesion to the gasket so that the gaskets do not release PTFE and give off their color when handled, do not loose their non-stick properties when stored over long periods of time, and can be stacked harmlessly on top of one another immediately after application of the coating.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.