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. 06, 1981
Filed:
Oct. 23, 1978
Donald E Van Arnam, Ontario, CA (US);
Avery International Corporation, San Marino, CA (US);
Abstract
A method is disclosed for forming a retroreflective sheeting having a plurality of retroreflective cube-corner prisms distributed over one of its surfaces such that the prisms are disposed in a planar array having a plurality of zones of prisms having differing angular orientations such that the zones have differing retroreflective brightness when illuminated by a light beam at a high angle of incidence. The method comprises clamping a plurality of pins together such that the ends of the pins form a substantially planar surface, inscribing the planar surface for forming thereon a continuous pattern of solid trigonal pyramids with internal dihedral angles of 90 degrees, releasing the bundle of pins and rotating the individual pins for changing the angular orientation of the formed trigonal pyramids on adjacent pins, reclamping the pins together and using the inscribed surface of the bundle of pins for forming a mold containing cube-corner prism cavities, and producing prismatic retroreflective sheeting by embossing, molding or casting in such mold.