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. 21, 1997
Filed:
Nov. 16, 1994
John C Chang, Naperville, IL (US);
Richard H Johnson, Lemont, IL (US);
Wallace Computer Services, Inc., Hillside, IL (US);
Abstract
A pressure and heat-sensitive composition comprising chromogen-containing pressure-rupturable microcapsules and heat-sensitive color developer useful for verification of document authenticity system when applied as a localized coating on documents, such as checks and prescriptions. Quickly striking the chromogenic composition with a fingernail or blunt object to generate pressure and heat in the coating produces a colored image by friction. The chromogenic composition possesses a fugitive characteristic, whereby the colored image gradually disappears and can be made to reappear when the chromogenic coating is again subjected to external pressure and heat. This feature can be used for repeated verification of the authenticity of the document.