| definition |
- CFCs are very stable chemical compounds, used in refrigerants, solvent, and
(in the past in the U.S.) aerosols, which release chlorine (important) and fluorine (less important) into the upper atmosphere. In the stratosphere,
CFCs are photolyzed (by incoming solar UV) to form carbon dioxide, CO2,
hydrogen fluoride, HF, and ultimately (after multiple UV absorption events) chlorine radicals. These chlorine species are crucial in the destruction of the ozone layer over Antarctica and probably elsewhere (see chlorine). [Environmental Science and Technology; v 28; pages 1619-1622;
1994.]
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| Abstract from DBPedia | Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are fully or partly halogenated hydrocarbons that contain carbon (C), hydrogen (H), chlorine (Cl), and fluorine (F), produced as volatile derivatives of methane, ethane, and propane. They are also commonly known by the DuPont brand name Freon. The most common representative is dichlorodifluoromethane (R-12 or Freon-12). Many CFCs have been widely used as refrigerants, propellants (in aerosol applications), and solvents. Because CFCs contribute to ozone depletion in the upper atmosphere, the manufacture of such compounds has been phased out under the Montreal Protocol, and they are being replaced with other products such as hydrofluorocarbons (HFCs) including R-410A and R-134a.フロン類（フロンるい）は、炭素と水素の他、フッ素や塩素や臭素などハロゲンを多く含む化合物の総称。場合によって指す物質の範囲は異なる。 冷媒や溶剤として20世紀中盤に大量に使用されたが、オゾン層破壊の原因物質ならびに温室効果ガスであることが明らかとなり、今日ではモントリオール議定書をはじめ様々な国際協定・法律によって、先進国を中心に使用には大幅な制限がかけられている。 フロンという呼び方は、日本でつけられた俗称である。日本以外ではデュポン社の商品名であり、商標のフレオン (freon) で呼ばれることが多い。 (Source: http://dbpedia.org/resource/Chlorofluorocarbon) |
