Durable glass elements
CA 1105949 A · Owner: Minnesota Mining And Manufacturing Company · Inventors: Tung, Chi F.; Fellows, Benjamin T.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Glass microspheres and other glass elements based on B2O3, BaO, and TiO2 have an improved combination of crushing strength, index of refraction and, especially in, some formulations, chemical resistance. The microspheres are especially adapted for use as retroreflective elements in pavement markings. Summarizing, ingredients of the new glass elements, in weight-percentages are: B2O3 5-60, TiO2 20-50, BaO and/or SrO 10-35 Alkali-metal oxide, selected from Na2O and K2O 0-15 SiO2 0-40, All other ingredients 0-15.
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
- Granted July 28, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 28, 1998.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.