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US 4,788,009 AGranted
Method of preparing rosin esters of improved thermal stability with inorganic salt of phosphorous or hypophosphorous acid
AssigneeUnion Camp Corporation
InventorRobert W. Johnson, Jr.
Life of this patent
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Abstract
Alkali metal and alkaline earth metal salts of hypophosphorous and phosphorous acid are used to catalyze the esterification of rosin with a polyol. The method is an improvement in that reaction time is shortened and the ester product exhibits improved color and thermal stability.
Claims12
A method of preparing a polyol ester of rosin, which comprises;
- esterifying the rosin with the polyol in the presence of a catalytic proportion of a catalyst compound selected from the group consisting of alkali metal salts of phosphorous acid, alkaline earth metal salts of phosphorous acid, alkali metal salts of hypophosphorous acid or alkaline earth metal salts of hypophosphorous acid.
Dependencies are inferred from the claim text.