Thermoplastic films for heat seaming roof sheeting and method for covering roofs
CA 2075599 A1 · Owner: Davis, James A. · Inventors: Davis, James A.; Valaitis, Joseph K.; Lohr, D. Frederick
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A laminate seam of flat rubber sheet material for roofing comprising two layers (10 11) of the sheet material at least one layer of which is uncured or cured and one layer of a thermoplastic film (14) interposed between the overlapped edges (12,13) of the two layers of sheeting material to form a seam without the use of an adhesive. A method for covering a roof comprises the steps of applying a thermoplastic film (14) to the edge (12) of at least one layer of a flat rubber sheet material (10); applying a second layer of flat rubber sheet material (11) overlapping the thermoplastic film and the edge of the first flat rubber sheet material; heating the overlapped area to a temperature …
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 August 7, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 7, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 7, 2014.
- 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.