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:
Jun. 01, 1982
Filed:
Feb. 17, 1981
John McCartney, Chester County, PA (US);
Norwood Industries, Inc., Malvern, PA (US);
Abstract
An aqueous polyurethane composition capable of thermal coagulation is disclosed. The polyurethane composition is comprised of an aqueous polyurethane dispersion having anionic groups covalently bonded to the polymer chain and solubilized by the addition of a cationic compound which forms a salt with the anionic group. The composition also includes a compound which, when heated in an aqueous solution, generates acid which causes displacement of the cationic compound from the covalently bonded anionic groups. A method of forming a composite sheet material is also disclosed. The composite sheet material is formed by impregnating a porous sheet material with the polyurethane composition and heating the impregnant to generate acid causing coagulation of the polyurethane dispersion in the porous sheet material. The impregnant is dried to form a composite sheet material.