Colorimetry

Deane Brewster Judd

Jan 1950 · U.S. Government Printing Office

About this ebook

"The judgment of color permeates our industrial life. The farmer finds his vegetables and fruits often graded and priced according to color. Raw wool, cotton, and silk are graded and priced according to color. Only in this way can the textile manufacturer produce goods of uniform color at a price low enough to sell. Oils and resins used for paint have their colors measured with extreme care, and pigments and dyes likewise. Poor quality edible oils (cottonseed, coconut, olive, peanut) can often be detected by color ; and light-colored cooking oils bring a premium price apart from quality because bakers know they can sell the resulting light-colored cakes and pies without any trouble. Color measurement is especially vital in mass production. The assembly of parts from different sources to make a complicated machine like a refrigerator often requires a color specification for each of several parts. The white plastic door to the freezing unit must be related in color to the interior walls of the refrigerator by color tolerances no less important to the final sale than are the length and width tolerances that insure the fit of the door. There is scarcely a segment of industry untouched by color considerations. Precise judgment of color is made possible by color measurement, or colorimetry. During the past two decades the National Bureau of Standards has played a leading part in establishing practical working standards of color and in setting up and administering color tolerances. These standards and methods have been described in some scores of scientific and technical publications. It is the purpose of this Circular to bring together this information in concise form, and by giving the basis for each technique to show more clearly how they supplement each other than has been possible in the several separate descriptions of them now available. It is hoped that this information will still further facilitate the purchase and sale of commodities and manufactured goods on a fair basis. Conformity to a color requirement can now be determined with the same assurance as size, shape, or strength."--Preface.