Patent Yard Sign in
Expired Canadian patentCanada

Method for making flexible retroreflective sheet material

CA 2040711 C · Owner: Martin, David Charles · Inventors: Martin, David Charles

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

Open the CIPO record

Abstract From the Canadian patent

A flexible retroreflective sheet material is formed by adhering a first face of a first flexible synthetic resin sheet material to a synthetic resin second sheet material by a first adhesive which preferentially adheres to the second sheet material. On the second face of said first sheet material are thereafter formed closely spaced retroreflective microprisms having a height of 0.001-0.010 inches. A second adhesive is applied to the second face of said first sheet and firmly engages therewith. A flexible backing material is adhered to the second adhesive over the second face. Lastly the second sheet material and first adhesive are stripped from the first sheet material to produce a firmly …

Read the whole patent

Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Filed April 17, 1991 and granted January 2, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 17, 2011.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 17, 2013.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledApril 17, 1991
GrantedJanuary 2, 1996
Term endedApril 17, 2011
Patent numberCA 2040711 C
Classification (IPC)G02B5/12 +2 more

Timeline

Timeline From CIPO dates

1992199419961998200020022004200620082010Application filedApril 17, 1991Patent grantedJan 2, 1996Term endedApril 17, 2011

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.