Patent GB-827361-A (GB)
Title: Improvements in or relating to fatty condensation products
Inventor: MIKUSCH-BUCHBERG JOHANNES DONA
IPC: C11C3/00
Filed: 1954-11-30
Abstract: Drying compositions for use in paints comprise condensation products, of iodine value of at least 100, containing at least 20% of unsaponifiable matter obtainable by heating fatty acids of the formula RCOOH, where R is an unsubstituted hydrocarbon chain radical containing a methylene group by which it is attached directly to the carboxyl group and containing at least 5 carbon atoms at temperatures of 220 DEG  to 330 DEG  C. in the presence of an oxygen-containing compound of boron, water liberated in the process being continually removed and the reaction continued until the product contains not less than 20% of unsaponifiable matter of mean molecular weight not less than three times that of the initial fatty acid (see Group IV (b)).  The condensation products may be derived from the fatty acids of unsaturated vegetable or marine oils many of which are specified. Drying compositions are obtained by adding lead and manganese naphthenates to the condensation products obtained from the fatty acids derived from soya bean oil, herring oil, ground nut oil, tall oil and sunflower soapstock acid oil.  An oleo resinous varnish is prepared from a soya bean oil fatty acid condensation product, turpentine, mineral spirit and cobalt drier.ALSO:A process for preparing condensation products comprises heating fatty acids at temperatures of 220 DEG  to 330 DEG C. in the presence of a catalyst which is an oxygen-containing compound of boron, water liberated in the reaction being continually removed from the reaction zone while the loss of the major part of the acid is avoided, the reaction being continued at least until the product contains a substantial proportion (not less than 20% of its weight) of unsaponifiable matter of mean molecular weight not less than three times that of the initial fatty acid.  The initial reaction mixture may contain a fatty ketone in addition to the fatty acid.  The invention further comprises a condensation product of fatty acid containing at least 20% by weight of unsaponifiable matter, the molecule of which contains at least three hydrocarbon radicals, all being the hydrocarbon radicals of such acid or differing from such radicals only in having a chain shorter by one carbon atom, the said product being obtainable by the first process set forth above.  The term "fatty acid" is defined as an acid of the formula RCOOH where R is an unsubstituted hydrocarbon chain radical containing a methylene group by which it is attached directly to the carboxyl group and containing at least 5 carbon atoms and the term "fatty ketone" is defined as a ketone of the formula R.CO.R1, where R and R1 satisfy the definition of R given above.  The fatty ketones may be derived from the same or different fatty acids from those present in the mixture.  The fatty acids may contain one or more double bonds, e.g. as in linoleic or linolenic acid or the unsaturated acids occurring in herring, whale, pilchard, sardine, linseed, groundnut, cottonseed, safflower, sunflower, soyabean, rapeseed and tall oils.  Saturated fatty acids specified are caprylic, capric, lauric and stearic acids.  The starting materials may contain minor amounts of, e.g., mono-, di- or tri-glycerides or resin acids.  Catalysts specified include boric acid, boric oxide, esters of boric acid, e.g. boric acid trimethyl, triethyl and mannitol esters, the mixed anhydride of boric acid and acetic acid or higher fatty acids, e.g. that obtained from groundnut oil.  The catalyst may be supported, e.g. on an oxide of silicon, kieselguhr, diatomite or silica gel.  The process may be carried out in a current of inert gas or in the presence of an inert water-immiscible solvent or under vacuum. Preferably the process is carried out so that refluxing of the fatty acids and higher boiling compounds occurs.  Solvents specified for use in the process are xylene, tetra- and deca-hydronaphthalene and petrol fractions. Unchanged fatty acid may be extracted from the products, e.g. with alcohol, or may be distilled off under vacuum.  Condensation products of the invention with iodine values, determined by Wijs' method, of 100 or more are employed as drying materials (see Group III). Examples are furnished.  A ketone for use, in admixture with groundnut fatty acids as a starting material, is obtained by heating a fraction of groundnut oil fatty acids with magnesium oxide.