Device for preventing drying of ink in writing instrument
CA 1231672 A · Owner: Sakura Color Products Corporation · Inventors: Ozu, Tatsuya; Yamamoto, Hiroyoshi; Inoue, Shigeyasu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A device for preventing drying of ink in the writing instrument using ink and, in particular the writing instru-, ment provided with a tubular holder made of synthetic resin. In the writing instrument internally provided with a tubular ink-cartridge containing ink, a liquid retainer impregnated with liquid whose vapor pressure is higher than that of ink in the ink-cartridge is provided in the inner space of the holder so as to control evaporation of ink from the cartridge by the use of vapor evaporating from the abovesaid liquid and to prevent total or partial loss of applicability of the writing instrument to writing even after the instrument is kept unused for a long time.
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 January 19, 1988. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 19, 2005.
- 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.