Novel method for preparing precipitated silica, novel aluminium-containing precipitated silicas, and use thereof for reinforcing elastomers
CA 2191487 C · Owner: Rhone-Poulenc Chimie · Inventors: Cochet, Philippe; Chevallier, Yvonick; Bomal, Yves
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A novel method for preparing precipitated silica having a good dispersibility and highly satisfactory reinforcing properties is disclosed. Novel precipitated silicas in the form of a powder substantially spherical beads or granules are also disclosed. Said silicas are characterised in that they have a CTAB specific surface area of 100-240 m?2¿/g a DOP oil absorption of less than 300 ml/100g a pore distribution such that the pore volume consisting of pores with a diameter of 175-275 .ANG. is less than 50 % of the pore volume consisting of pores with a diameter of at most 400 .ANG. a mean diameter after ultrasonic disintegration of less than 5 µm and an aluminium content of at least 0.35 wt.% …
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 March 28, 1996 and granted January 16, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 28, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 28, 2018.
- 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.