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:
Aug. 22, 1989
Filed:
Mar. 21, 1986
Applicant:
Inventors:
Fred K Suzuki, Arlington Heights, IL (US);
Sharon M Mead, Streamwood, IL (US);
Noble H Yoshida, Arlington Heights, IL (US);
Robert H Dobberstein, Arlington Heights, IL (US);
Assignee:
Biosynergy, Inc., Arlington Heights, IL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C09K / ; G01K / ;
U.S. Cl.
CPC ...
2522997 ; 2524081 ; 374106 ; 374162 ;
Abstract
Described are cholesteric liquid crystal formulations suitable for use as indicators of time and/or temperature, and methods for reliably characterizing and reproducing initial and subsequent batches of such cholesteric liquid crystal formulations. The formulations have a time-dependent, temperature-dependent limit in a pseudo-irreversible liquid crystal phase wherein when said limit is exceeded, the formulations exhibit a color change which is irreversible by cooling.