GB341012A - Improvement in synthetic resin - Google Patents

Abstract

Paints.--A modified alkyl resin prepared by esterifying a polyhydric alcohol with a polybasic acid and pure beta-eleostearic acid with or without a resin acid is used as a component of a paint or coating composition. In an example, a mixture of glycerol, phthalic anhydride, raw Congo gum and beta-eleostearic acid is heated gradually to 180 DEG C. and subsequently heated to 250 DEG C. for a short period; it is then cut hot in high flash-point solvent naphtha. In place of glycerol, other polyhydric alcohols may be used, such as glycol, mannitol, penta-erythritol; as examples of other polybasic acids, malic, succinic, camphoric, tartaric and citric acids are specified. A resin solution prepared according to the Example may have a liquid cobalt dryer incorporated to form a quick drying varnish. The liquid cobalt dryer may be a 10 per cent solution of cobalt linoleate in turpentine and may contain 0,75 per cent of cobalt as metal, based upon the weight of liquid dryer. Beta-eleostearic acid is prepared from china wood oil by treatment with ,03 to ,05 per cent by weight of iodine in a dilute alcoholic solution (2,5 to 5 per cent). The solution is allowed to stand until it has set to a substantially solid mass, usually for several days, then mixed with about one-third its weight of acetone and centrifuged to remove the liquid residue. The solid residue in the centrifugue is washed several times with acetone and a yield obtained of approximately 50 per cent of solid beta-eleostearin of the raw oil used. The acid is obtained by treating the beta-eleostearin with a solution of sodium hydroxide and subsequently treating the sodium eleostearate with dilute hydrochloric acid.ALSO:Ester condensation products.-A modified alkyd resin is prepared by esterifying a polyhydric alcohol with a polybasic acid and pure betaeleostearic acid with or without a resin acid. In an example, a mixture of glycerol, phthalic anhydride, raw Congo gum and betaeleostearic acid is heated gradually to 180 DEG C. and subsequently heated to 250 DEG C. for a short period. It is then cut hot in high flash-point solvent naphtha. In place of glycerol, other polyhydric alcohols may be used, such as glycol, mannitol, pentaerythritol; as examples of other polybasic acids, malic, succinic, camphoric, tartaric and citric acids are specified. A resin solution prepared according to the example may have a liquid cobalt dryer incorporated to form a quick drying varnish. The liquid cobalt dryer may be a 10 per cent solution of cobalt linoleate in turpentine and may contain 0,75 per cent of cobalt as metal, based upon the weight of liquid dryer. Beta-eleostearic acid is prepared from china wood oil by treatment with ,03 to ,05 per cent by weight of iodine in a dilute alcoholic solution (2,5 to 5 per cent). The solution is allowed to stand until it has set to a substantially solid mass, usually for several days, then mixed with about one-third its weight of acetone and centrifuged to remove the liquid residue. The solid residue in the centrifuge is washed several times with acetone and a yield obtained of approximately 50 per cent of solid beta-elaeostearin of the raw oil used. The acid is obtained by treating the beta-elaeostearin with a solution of sodium hydroxide and subsequently treating the sodium eleostearate with dilute hydrochloric acid.