GB309383A - Paper sizing agents - Google Patents

Abstract

309,383. Marks, E. C. R., (Alox Chemical Corporation). Oct. 6, 1927. Drawings to Specification. Sizing and weighting.-Organic hydroxy-acids of high molecular weight, insoluble in petroleum and suitable for use in sizing paper are produced continuously from a petroleum distillate which may be of 36-40‹ BÚ. and mostly distilling between 260 and 360‹ C. by oxidizing the oil in liquid phase with air or other oxidizing gas at 120-155‹ C. and under pressure (200-350 lb.), with or without a catalyst such as a manganese copper or iron compound (manganese oleate being mentioned) until a material quantity not greater than 10 per cent of the hydroxy acids are produced, the acids being separated treated with steam at above 150‹ C., and converted into soaps. The soaps are added to the paper stock with the addition of a salt such as an, aluminium salt. The oxidized material passing to the still consists mainly of carboxylic and hydroxycarboxylic acids and ketones of high molecular weight. It is heated to about 150‹ C. for instance by a steam coil (water and ketones, passing off) and steam is then passed through the material to expel all volatile matter. After cooling, some heavy sludge may separate and is carefully drawn off from the " size acid." The " size acid " is dissolved in aqueous caustic soda or sodium carbonate. The soap solution is added to the paper pulp in the beating-engine, followed by a suitable precipitant such as aluminium sulphate or alum. If desired the soaps may be made with an excess of alkali and bleached with chlorine, the excess of alkali being then neutralized by an acid. The process may be continuous.