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:
Jul. 11, 1995
Filed:
Aug. 23, 1993
John C Chang, Naperville, IL (US);
Donald Hoffmann, Elmhurst, IL (US);
Wallace Computer Services, Inc., Hillside, IL (US);
Abstract
A hidden entry system comprises a document having a first substrate bearing a localized latent image spaced apart from a removable image-developing device comprising a second substrate having a first surface and a second surface, the first surface of the second substrate bearing a chromogenic composition comprising an image-forming co-reactant, the image-forming co-reactant being a chromogen or a color developer, the second surface of the second substrate bearing a pressure-sensitive adhesive. The image developing device is in superposed relation with the first substrate with the pressure sensitive coating being releasably attached to the first substrate.