Polysaccharide derivatives containing aldehyde groups, their preparation from the corresponding acetals and use as paper additives
CA 1292986 C · Owner: National Starch And Chemical Corporation · Inventors: Solarek, Daniel B.; Jobe, Patrick G.; Billmers, Robert L.
Overview
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Polysaccharide aldehydes having the formula Sacch-O-CH2-CH=CH-CHO Saach-O-CH2-C=C-CHO, , , , , , , such as , ;, starch, cellulose, and gum aldehydes are useful for imparting wet, dry,-, or temporary wet strength to paper. They are prepared by a non-oxidative method which involves reacting the polysaccharide base in the presence of, alkali, with a derivatizing acetal reagent of general formula , R19 being a divalent organic group, and then hydrolyzing the acetal by adjusting the pH to less than 7, preferably 2 4. In the formulas n is, 1-3; R11 and R12 are independently an alkyl aryl, aralkyl, or alkaryl, group when n is 1 R11 or R12 is one of the groups when n is 2 or R11 and, R12 are not …
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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 December 10, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 10, 2008.
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