WCO Explanatory Notes reproduced for reference. © World Customs Organization. Verify against official WCO publication.
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.
1.- This Chapter does not cover : (a) Separate chemically defined elements or compounds with the exception of the following : (1) Artificial graphite (heading 38.01); (2) Insecticides, rodenticides, fungicides, herbicides, anti-sprouting products and plant-growth regulators, disinfectants and similar products, put up as described in heading 38.08; (3) Products put up as charges for fire-extinguishers or put up in fire-extinguishing grenades (heading 38.13); (4) Certified reference materials specified in Note 2 below; (5) Products specified in Note 3 (a) or 3 (c) below; (b) Mixtures of chemicals with foodstuffs or other substances with nutritive value, of a kind used in the preparation of human foodstuffs (generally heading 21.06); (c) Products of heading 24.04; (d) Slag, ash and residues (including sludges, other than sewage sludge), containing metals, arsenic or their mixtures and meeting the requirements of Note 3 (a) or 3 (b) to Chapter 26 (heading 26.20); (e) Medicaments (heading 30.03 or 30.04); or (f) Spent catalysts of a kind used for the extraction of base metals or for the manufacture of chemical compounds of base metals (heading 26.20), spent catalysts of a kind used principally for the recovery of precious metal (heading 71.12) or catalysts consisting of metals or metal alloys in the form of, for example, finely divided powder or woven gauze (Section XIV or XV). 2.- (A) For the purpose of heading 38.22, the expression “certified reference materials” means reference materials which are accompanied by a certificate which indicates the values of the certified properties, the methods used to determine these values and the degree of certainty associated with each value and which are suitable for analytical, calibrating or referencing purposes. (B) With the exception of the products of Chapter 28 or 29, for the classification of certified reference materials, heading 38.22 shall take precedence over any other heading in the Nomenclature. 3.- Heading 38.24 includes the following goods which are not to be classified in any other heading of the Nomenclature : (a) Cultured crystals (other than optical elements) weighing not less than 2.5 g each, of magnesium oxide or of the halides of the alkali or alkaline-earth metals; (b) Fusel oil; Dippel's oil; (c) Ink removers put up in packings for retail sale; (d) Stencil correctors, other correcting fluids and correction tapes (other than those of heading 96.12), put up in packings for retail sale; and (e) Ceramic firing testers, fusible (for example, Seger cones). 4.- Throughout the Nomenclature, “municipal waste” means waste of a kind collected from households, hotels, restaurants, hospitals, shops, offices, etc., road and pavement sweepings, as well as construction and demolition waste. Municipal waste generally contains a large variety of materials such as plastics, rubber, wood, paper, textiles, glass, metals, food materials, broken furniture and other damaged or discarded articles. The term “municipal waste”, however, does not cover : (a) Individual materials or articles segregated from the waste, for example wastes of plastics, rubber, wood, paper, textiles, glass or metals, electrical and electronic waste and scrap (including spent batteries) which fall in their appropriate headings of the Nomenclature; (b) Industrial waste;