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Linseed oil, also known as flaxseed oil, is a colourless to yellowish oil obtained from the dried, ripened seeds of the flax plant (''Linum usitatissimum''). The oil is obtained by pressing, sometimes followed by solvent extraction. Linseed oil is a ''drying oil'', meaning it can polymerize into a solid form. Due to its polymer-forming properties, linseed oil can be used on its own or blended with combinations of other oils, resins or solvents as an impregnator, drying oil finish or varnish in wood finishing, as a pigment binder in oil paints, as a plasticizer and hardener in putty, and in the manufacture of linoleum. Linseed oil use has declined over the past several decades with increased availability of synthetic alkyd resins—which function similarly but resist yellowing. Linseed oil is an edible oil in demand as a nutritional supplement, as a source of α-Linolenic acid, (an omega-3 fatty acid). In parts of Europe, it is traditionally eaten with potatoes and quark. It is regarded as a delicacy due to its hearty taste, which enhances the flavour of quark, which is otherwise bland. ==Chemical aspects== Linseed oil is a triglyceride, like other fats. Linseed oil is distinctive for its unusually large amount of α-linolenic acid, which has a distinctive reaction with oxygen in air. Specifically, the fatty acids in a typical linseed oil are of the following types:〔A. G. Vereshagin and G. V. Novitskaya (1965) The triglyceride composition of linseed oil. Journal of the American Oil Chemists' Society 42, 970-974. ()〕 *The triply unsaturated α-linolenic acid (51.9-55.2%), *The saturated acids palmitic acid (about 7%) and stearic acid (3.4-4.6%), *The monounsaturated oleic acid (18.5-22.6%), *The doubly unsaturated linoleic acid (14.2-17%). Having a high content of di- and triunsaturated esters, linseed oil is particularly susceptible to polymerization reactions upon exposure to oxygen in air. This polymerization, which is called ''drying,'' results in the rigidification of the material. The drying process can be so exothermic as to pose a fire hazard under certain circumstances. To prevent premature drying, linseed oil-based products (oil paints, putty) should be stored in air-tight containers. Like some other drying oils, linseed oil exhibits fluorescence under UV light after degradation.〔E. René de la Rie, (Fluorescence of Paint and Varnish Layers (Part II) ), Studies in Conservation Vol. 27, No. 2 (1982), pp65-69〕 : 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「linseed oil」の詳細全文を読む スポンサード リンク
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