Laundry evaluation piece including bleaching activity indicator
CA 2055152 A1 · Owner: Anderson, Terry K. · Inventors: Howard, Eugene R.; Anderson, Terry K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The effect of chlorine concentration in laundry solutions on the life of the laundered fabrics is signalled by a chlorine concentration indicator swatch, in which contrastingly hued dyes including one whose chlorine resistance is measurably stronger than the other, are combined to dye fabric test swatches an initial color. Including such fabric test swatches in chlorinecontaining laundry solutions causes visually discernable changes in the hues of the swatches as the bleaching action progressively subtracts those dyes of lesser resistance. Chlorine concentration which, if excessive, seriously impairs laundered fabrics may be, determined by visually inspecting the swatches.
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 November 7, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 7, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 7, 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.
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.