Bookbinding and the Conservation of Books
A Dictionary of Descriptive Terminology

 Previous item  Up One Level Next item

acid dyes

A very large class of dyes containing acidic groups, such as the sodium salts of sulfonic acids or phenolic groups. They are more soluble and have less tinctorial value than BASIC DYES but they also have greater light fastness. See: FAST COLORS . They do not form lakes with tannin. Acid dyes are used in dyeing leather, paper, etc., and their particular value lies in their ability to produce brighter, more uniform colors. They are normally applied from an acid dye liquor (acetic, formic, or sulfuric acid); however, unless applied from a neutral or only slightly acid dyebath, i.e., pH of 6.0 to 7.0, their use is likely to result in acid degradation of the material dyed. See also: FUGITIVE COLORS ; LAKE .

(17 , 67 , 72 , 363 )

[Search all CoOL documents]