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|Section2= |Section3= |Section6= |Section7= |Section8= }} Formaldehyde is a naturally-occurring organic compound with the formula CH2O. It is the simplest aldehyde and is also known by its systematic name methanal. The common name of this substance comes from its similarity and relation to formic acid. Formaldehyde is an important precursor to many other materials and chemical compounds. In 1996, the installed capacity for the production of formaldehyde was estimated to be 8.7 million tons per year.〔Günther Reuss, Walter Disteldorf, Armin Otto Gamer, Albrecht Hilt "Formaldehyde" in ''Ullmann's Encyclopedia of Industrial Chemistry'', 2002, Wiley-VCH, Weinheim. 〕 It is mainly used in the production of industrial resins, e.g., for particle board and coatings. In view of its widespread use, toxicity, and volatility, formaldehyde is a significant consideration for human health.〔 〕 In 2011, the US National Toxicology Program described formaldehyde as "known to be a human carcinogen". ==Forms of formaldehyde== Formaldehyde is more complicated than many simple carbon compounds in that it adopts several different forms. As a gas, formaldehyde is colorless and has a characteristic pungent, irritating odor. Upon condensation, the gas converts to various other forms of formaldehyde (with different chemical formulas) that are of more practical value. One important derivative is the cyclic trimer metaformaldehyde or 1,3,5-trioxane with the formula (CH2O)3. There is also a linear polymer called paraformaldehyde. These compounds have similar chemical properties and are often used interchangeably. When dissolved in water, formaldehyde also forms a hydrate, methanediol, with the formula H2C(OH)2. This compound also exists in equilibrium with various oligomers (short polymers), depending on the concentration and temperature. A saturated water solution, of about 40% formaldehyde by volume or 37% by mass, is called "100% formalin". A small amount of stabilizer, such as methanol, is usually added to suppress oxidation and polymerization. A typical commercial grade formalin may contain 10–12% methanol in addition to various metallic impurities. Aqueous formaldehyde is also called 'formalin'. 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「formaldehyde」の詳細全文を読む スポンサード リンク
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