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. 03, 1978
Filed:
Feb. 04, 1976
Mortimer M Labes, Philadelphia, PA (US);
Temple University, Philadelphia, PA (US);
Abstract
Cumulative temperature dosimeter utilizes a temperature dependent reaction in a cholesteric liquid crystal composition to produce a color change indicative of temperature exposure over a period of time. Typically, the composition includes, as a solvent, a cholesteric liquid crystal, such as a mixture of p-methoxy-p'-n-butyl-azoxybenzene, cholesteryl nonanoate, cholestyl chloride, and cholesteryl oleyl carbonate. One or more solutes are included, the solutes being reactive at a rate which is temperature dependent, to cause either generation or consumption of mesogenic compounds. In turn, the pitch of the solvent, observable as a visible color change, is affected in proportion to the cumulative temperature exposure of the composition.