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Bleach refers to a number of chemicals which remove color, whiten or disinfect, often by oxidation. The bleaching process has been known for millennia, but the chemicals currently used for bleaching resulted from the work of several 18th century scientists. Chlorine is the basis for the most commonly used bleaches, for example, the solution of sodium hypochlorite, which is so ubiquitous that most simply call it "bleach", and calcium hypochlorite, the active compound in "bleaching powder". Oxidizing bleaching agents that do not contain chlorine most often are based on peroxides, such as hydrogen peroxide, sodium percarbonate and sodium perborate. While most bleaches are oxidizing agents, some are reducing agents such as sodium dithionite and sodium borohydride. Bleaches are used as household chemicals to whiten clothes and remove stains and as disinfectants, primarily in the bathroom and kitchen. Many bleaches have strong bactericidal properties, and are used for disinfecting and sterilizing and thus are used in swimming pool sanitation to control bacteria, viruses and algae and in any institution where sterile conditions are needed. They are also used in many industrial processes, notably in the bleaching of wood pulp. Bleach is also used for removing mildew, killing weeds and increasing the longevity of flowers.〔http://www.rd.com/home/cleaning-organizing/12-smart-ways-to-use-bleach/〕 == History == The earliest form of bleaching involved spreading fabrics and cloth out in a bleachfield to be whitened by the action of the sun and water.〔 Modern bleaches resulted from the work of 18th century scientists including Swedish chemist Carl Wilhelm Scheele, who discovered chlorine,〔 French scientists Claude Berthollet, who recognized that chlorine could be used to bleach fabrics〔 and who first made sodium hypochlorite (''Eau de Javel'', or Javel water, named after a quarter in Paris where it was produced) and Antoine Germain Labarraque, who discovered the disinfecting ability of hypochlorites. Scottish chemist and industrialist Charles Tennant first produced a solution of calcium hypochlorite, then solid calcium hypochlorite (bleaching powder).〔 Louis Jacques Thénard first produced hydrogen peroxide in 1818 by reacting barium peroxide with nitric acid. Hydrogen peroxide was first used for bleaching in 1882, but did not become commercially important until after 1930. Sodium perborate as a laundry bleach had been used in Europe since the early twentieth century, but did not become popular in North America until the 1980s. 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「Bleach」の詳細全文を読む スポンサード リンク
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