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. 12, 1988
Filed:
Apr. 24, 1987
Bruce A Lent, Oak Park, IL (US);
Paul N Elue, Chicago, IL (US);
Videojet Systems International, Inc., Elk Grove Village, IL (US);
Abstract
The thermochromic jet ink compositions of the present invention undergo color changes in response to changes in thermal environment. Additionally, the inks comprise a combination of solvent, dyes and other essential ingredients which make them suitable for ink jet printing, or printing which is effected without contact between the printing device and the substrate on which the printed characters are deposited. The present invention provides thermochromic ink compositions with enhanced thermal specificity. Moreover, these inks are capable of indicating that the substrate has been exposed to such a specific thermal environment for at least a specified minimal period of time. The color change so effected is irreversible and does not require steam or moisture to leach out selected components of the composition thereby providing a more rapid and distinct color change. The most notable use of the present invention is to indicate completion of pasteurization or sterilization of the substrate or its contents.