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:
Feb. 25, 1997
Filed:
Oct. 06, 1994
John C Chang, Naperville, IL (US);
Wallace Computer Services, Inc., Hillside, IL (US);
Abstract
A pressure-sensitive, laser printer heat-resistant verification system for preventing unauthorized photoduplication of security documents comprising a support bearing an information area comprising a visible principal image, and a verification area comprising a localized, autogenous coating of a pressure-sensitive chromogenic composition for producing a visible colored image by external pressure. The chromogenic composition comprises (a) pressure-rupturable microcapsules containing a chromogen and (b) a color developer capable of reacting with the chromogen to form a visible image. The pressure-rupturable microcapsules and color developer are substantially coextensive on the support, and the verification area is spaced apart from the information area.