Foreword

The volume of publications concerned with metal cleaning continues at a level comparable with previous years, but the emphasis has gradually changed. New metals present new cleaning problems which are solved by advanced technics or combinations of older methods. Ultrasonic cleaning, in-place cleaning of equipment in plants or of pipe lines, and the cleaning of electronic components are receiving much consideration for the special problems involved. Over 100 references prior to 1958 have been found, those from 1958 to early 1960 totalling 114. As before, indices of subject, author, specification and patent numbers have been provided. While the references are numbered consecutively, additional references that fall within the dates previously covered have capital letters appended to the numbers to indicate their correct position, while still later references to be inserted where capital letters are already assigned have been given lower case letters (for example 72, 72A, 72Aa) to indicate reference priority. Covered are the fields of practical application, laboratory evaluation, theory, and references from other fields applicable to the subject.