The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 06, 1987
Filed:
Sep. 09, 1985
Arthur Z Moss, Wilmington, DE (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
Microporous polymeric films having good water vapor transmission rates and hydrostatic resistance to the penetration of liquid water are obtained by stretching a composition consisting of a matrix of a thermoplastic orientable polymer having a hydrophobic surface, a glass transition temperature of less than 25.degree. C., a Vicat softening point of more than about 25.degree. C., an ultimate elongation between those two temperatures of at least 100%, and a flexural modulus of less than 200 MPa and a particulate filler having an aspect ratio of less than 3, an average diameter of 0.05-50 m, a negligible attraction to the matrix polymer, and a surface tension no higher than that of the matrix polymer at the latter's melting temperature. Such films are useful in applications involving separation of liquids and vapors, e.g., in making 'breathing' waterproof garments or linings.