Patent GB-600705-A (GB)
Title: Improvements in or relating to the production of compositions containing modified castor oil fatty acid radicles
IPC: C09F5/06
Filed: 1944-03-31
Abstract: A drying oil composition is obtained by heating a castor oil fatty acid or a polyhydric alcohol ester thereof with an acidic varnish resin at a temperature between 500 DEG  and 630 DEG  F. for a period of time sufficient to effect at least partial dehydration of the fatty acid or ester.  Suitable esters of castor oil fatty acids are the pentaerythritol, mannitol and sorbitol esters and castor oil itself while suitable resins are rosin, Kauri and Congo copal, and rosin- or copal-modified phenol-formaldehyde resins. Gel formation during the reaction is minimized by melting the resin before adding the castor oil fatty acid or ester thereof or by adding a drying oil fatty acid such as linseed oil fatty acids. Any residual carboxyl groups may be esterified following the heat treatments by reaction with a polyhydric alcohol such as glycerol, ethylene glycol or pentaerythritol.  The drying oil composition may be blended with other drying oils such as linseed oil or alternatively drying oil fatty acids such as linseed oil fatty acids may be added after the heat treatment, but before the final esterification with a polyhydric alcohol.  In examples: (a) rosin and castor oil are heated together; (b) Congo copal and castor oil are heated together and the reaction mixture esterified with glycerine, and (c) Congo copal, castor oil and linseed oil fatty acids are heated together and, if desired, the reaction mixture is esterified with glycerine.  Varnishes are produced by dissolving the products of the examples in xylol with addition if desired of cobalt and lead naphthenate driers. Specification 533,593 is referred to.ALSO:A composition having air-drying properties is obtained by heating a castor oil fatty acid or a polyhydric alcohol ester thereof with an acidic varnish resin at a temperature between 500 DEG  and 630 DEG  F. for a period of time sufficient to effect at least partial dehydration of the fatty acid or ester.  Suitable esters of castor oil fatty acids are the pentaerythritol, mannitol and sorbitol esters and castor oil itself, while suitable resins are rosin, Kauri and Congo copal, and rosin- or copal-modified phenol-formaldehyde resins.  Gel formation during the reaction is minimized by melting the resin before adding the castor oil fatty acid or ester thereof or by adding a drying oil fatty acid such as linseed oil fatty acids.  Any residual carboxyl groups may be esterified following the heat treatment by reaction with a polyhydric alcohol such as glycerol, ethylene glycol or pentaerythritol.  The drying oil composition may be blended with other drying oils such as linseed oil or alternatively drying oil fatty acids such as linseed oil fatty acids may be added after the heat treatment, but before the final esterification with a polyhydric alcohol.  In examples: (a) rosin and castor oil are heated together; (b) Congo copal and castor oil are heated together and the reaction mixture esterified with glycerine; and (c) Congo copal, castor oil and linseed oil fatty acids are heated together and, if desired, the reaction mixture is esterified with glycerine.  Varnishes are produced by dissolving the products of the examples in xylol with addition, if desired, of cobalt and lead naphthenate driers.  Specification 533,593 is referred to.