释义 |
perborate Chem.|pɜːˈbɔəreɪt| [a. F. perborate (A. Étard 1880, in Compt. Rend. XCI. 932): see per-1 5 and borate.] Any of a number of strongly oxidizing derivatives of boric acid which contain peroxo-anions, and are usu. prepared by the action of hydrogen peroxide on borates; esp. the sodium salt, a white crystalline solid of empirical formula NaBO3.4H2O, which is widely used as a bleach and is a constituent of washing powders.
1881Chem. News 14 Jan. 25/2 He [sc. A. Étard] has obtained barium perborate,—Bo2O7BaH4 + H2O, a white amorphous insoluble salt. 1898Jrnl. Chem. Soc. LXXIV. ii. 427 The heat of decomposition by sulphuric acid was determined in the case of sodium perborate and ammonium perborate. 1916Chem. Abstr. X. 2803 Hereto⁓fore bleaching with persalts, such as perborate, has been more costly than bleaching with chloride of lime. 1959Observer 6 Sept. 18/4 Perborate bleach works only at high temperatures. 1959Guardian 28 Sept. 3/6 The woollen cardigan..had..changed colour..due to the perborate (a stain-removing bleach) added..to a soap powder. 1967E. L. Muetterties Chem. Boron & its Compounds iii. 192 The X-ray crystal structure determination of ‘sodium perborate’..reveals a dimeric tetrahedral configuration with dihedral angle equal to 64°:..and the anionic formula B2(O2)2(OH)42-·2Na+·6H2O. 1974Sci. Amer. Jan. 125/2 Sodium perborate is the cheapest and safest of all peroxy salts and is much used in detergents, particularly for very-hot-water washing. |