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:
Oct. 13, 1998
Filed:
Dec. 30, 1996
Yoshiyuki Nagaoka, Yamagata, JP;
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
A retroreflective sheeting have a multitude of retroreflective elements that include a layer of optical elements and a reflective element(s) that is positioned functionally behind the optical elements. The retroreflective elements are supported by a polymeric layer, and an adhesive layer positioned below the support layer. The adhesive layer contains a polyurethane crosslinked by at least an isocyanate compound. The polyurethane is polymerized from a component containing a polyol having at least one alkyl side chain in a molecule, and the adhesive has (i) a storage modulus of about 2.times.10.sup.7 to 8.times.10.sup.7 dyne per square centimeter when measured in a tensile mode at a frequency of 35 Hz and 25.degree. C., and (ii) a softening point of about 80.degree. C. to less than 200.degree. C.