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:
Jan. 27, 1981
Filed:
Jan. 30, 1979
Chi C Lee, Richmond, VA (US);
Richard E Ludwig, Newtown Square, PA (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
A security paper is provided in which identifying material is contained in a plane within the thickness of a bonded, nonwoven polyethylene film-fibril sheet having an opacity of at least 70% and a determination resistance of at least 60 grams per centimeter. A process for making such paper includes forming an assembly of two unbonded, lightly consolidated, nonwoven, polyethylene film-fibril sheets containing identifying material between them, compressing the assembly in an unheated nip at 17 to 85 kilograms per centimeter of assembly width and then self-bonding the compressed assembly while under restraint by contact with a heated drum. Such security paper is useful for bank notes, stock certificates, paper currency and the like.