Processes for bleaching kaolin clay, and ummineral or other inorganic material, decaulim bleached clay or other mineral milled, and the paper substrate having a coating ouenchedor

摘要

Process for bleaching kaolin clay, and ummineral or other inorganic material, decaulim bleached clay or other mineral milled, and the paper substrate having a coating ouenchedor ".Improved processes for bleaching deargila kaolin and other minerals are provided.Maisparticularmente, processes of the present invention employ ummaterial of hydrosulfite or bisulfite and a second agent dereduu00e7u00e3o,Preferably a reducing agent which contains umelemento group III, as a boroidreto, to increase abrilhu00e2ncia of kaolin clay and other minerals and reduce the color presenteneles.The processes of this invention are particularmenteu00fateis in industries that use the kaolin clays.