Lapping composition

摘要

A lapping composition which contains abrasive grains which are commercially available and which consists of plate alumina-powder prepared by milling and class:trying a sintered body of plate alumina obtained by calcinating aluminum hydroxide, and other plate alumina powder classified and prepared separately from but similarly to the first-mentioned plate alumina powder having average grain size which is in a range of from 1.3 times to 2.3 times as large as the average grain size of the first-mentioned plate alumina powder. Further provided is a lapping method with such a lapping composition by which the removal rate is improved and a lapped surface excellent in quality can be obtained.