Salts of rosin, of resin acids or of derivatives of rosin or resin

38.06 - Rosin and resin acids, and derivatives thereof; rosin spirit and rosin oils; run gums. 3806. I0 - Rosin and resin acids 3806.20 - Salts of rosin, of resin acids or of derivatives of rosin or resin acids, other than salts of rosin adducts 3806.30 3806.90 - Ester gums - Other (A) ROSIN AND RESIN ACIDS Both rosin and resin acids consist essentially of corn lex mixtures of abietic acid and allied acids with small amounts of non-acidic com onents. ?hey are solids, usually transparent and vitreous. Their colour may vary from pale ye ow to dark brown according to the amount of the impurities present. R Rosin and resin acids are obtained by the following processes : entine and similar terpenic solvents) (1) Separation of volatile terpenic products (spirits of during the distillation of oleoresinous matter obtaine in the form of an exudate from pine or other coniferous trees (pine resin, galipot, barras resin, etc.). (2) Solvent extraction from pine stump wood. (3) Fractional distillation of tall oil, a by-product of the pulp and paper industry. Rosin and resin acids are used in the e u f a c t u r e of certain soaps, for sizin paper, in the reparat~on of varnishes, polishes, mast~cs,inks, sealing-wax, binders for oundry cores, &ewers7 pitch, etc., and as raw material for the preparation of the derivatives and rosin oils described in Parts (B) to (D). f (El) SALTS OF ROSIN, OF RESIN ACIDS OR OF DERIVATIVES OF ROSIN OR RESIN ACIDS, OTHER THAN SALTS OF ROSIN ADDUCTS Resinates are used to increase the drying roperties of the oils used in the manufacture of varnishes or paints, and in the preparation o fungicides, disinfectants, etc. ? This group also includes hardened rosin which is obtained b treatin rosin or resin acids with, for example, calcium hydroxide (in a pro ortion of about 6 whic hardens it and renders it more suitable for use in the preparation o varnishes. 6) f P The heading excludes : (a) Precious metal resinates (heading 28.43) and the resinates of headings 28.44 to 28.46. (b) Prepared driers based on resinates (heading 32.11). (c) Resin soaps obtained by saponifying mixtures of higher fatty acids and rosin or resin acids (heading 34.01), and other washing preparations with a basis of resinates (heading 34.02). (C)ESTER GUMS Ester are obtained by esterification, with ethylene lycol, glycerol or other polyhydric i ortionated ~ a l c o b o c f rosin or resin acids or, of their oxidise , hydrogenated, d (dehydro enated) or polymerised derivatives. These ester gums are more plastic ti! an natural resins an this makes them suitable for mixing with pigments and other materials. % (D) OTHER (I) Derivatives of rosin and resin acids (1) Oxidised rosin and resin acids are usually obtained as a residual product of the distillation of extracts of the stumps of coniferous trees which have been left in the ground for a long time resulting in natural oxidation of their resin acid content. Rosin or resin acids may also be oxihsed artificially. Oxidised rosin and resin acids are used in the preparation of glues, emulsions, varnishes, paints, inks and for electrical insulation, etc. (2) Hydrogenated rosin and resin acids are obtained by treating rosin or resin acids with hydrogen in the resence of a catalyst. They are more resistant to oxidation than ordinary rosin an resin acids and discolour less readily under the action of light. They are used in the preparation of varnishes, soap, etc. d' (3) Disproportionated (dehydrogenated) rosin and resin acids are prepared, for example, by heating rosln or resin acids to a moderate temperature or, at hi tem erature, by the use of acid catalysis; sulphur and selenium are also use cata ysts. They are used in the preparation of varnishes, etc. ?i d (4) Polymerised rosin and resin acids are obtained by treating rosin or resin acids with sul huric acid, and used, in articular, in the preparation of varnishes of high viscosity an stability. The degree o! i polymerisation is very low. Polymerised rosin and resin acids are generally composed of dimer and unpolymerised acids and may also be referred to as dimerised rosin. ‘f (5) Monohydric alcohol esters of rosin or resin acids. The esters classified here include those known as " resinates or " abietates ", e.g., the methyl, ethyl and benzyl esters " and " methyl hydroabietate ", which are used, in particular, as plasticisers for cel~ulose lacquers. (6) Mixtures of di4ydmabiety1, tetrahydroabietyl and dehydroabietyl alcohols ('( abietyl alcohol ). (7) Rosin adducts and derivatives thereof. Rosin or resin acids modified with fumaric acid, maleic acid or its anhydride, used in the pr aration of allcyd resin, rosin size and inks. These adducts ma be subsequently esteri led wtth ethylene glycol, gl cerol or as salts other polyh dric alcoho s. This grou also includes salts of rosin adducts of rosin-m eic or of rosin-fumartc a ducts. r B "P SUCK (11) Rosin spirit and rosin oils These products are obtained, usually from rosin or resin acids, by distillation with superheated steam and a catalyst, or by destructive distillation. They are essentially complex mixtures of hydrocarbons and may contain organic acids in quantities varying according to distilling conditions. (1) Rosin spirit, which is the most volatile fraction, is a mobile, straw-coloured li uid with a pungent smell, used as a solvent for resins, in the manufacture of varnis es, paints, etc. % B d (2) Rosin oils are more or less thick, varying in colour and uality golden oils, white, green or brown oils) and have a smoky odour. They are chie y use for the preparation of lubricants, cutting oils, printing inks, ointments, varnishes, paints, etc. The heading does not cover : (a) Sulphonated rosin oils (heading 34.02). (b) The volatile constituents of the distillation of the oleoresinous exudates of living pine trees or other living coniferous trees (heading 38.05). (c) Rosin pitch (heading 38.07). (111) Run gums Run ms are obtained fiom the oleoresinous exudates of tropical forest trees by a process calleFgum running "which involves heating the exudates to render them soluble in drying oils. The most common source of run gums is copal.