Industrial Pitches
SourceIndustrial pitches comprise those coal-tar pitches that are used in the manufacture of other products, principally as saturants, plasticizers, or binders. They are produced by distillation from high-temperature coke-oven tars selected and blended to give the properties required in the finished product. To insure uniform performance under any of the widely diversified conditions of use, industrial pitches are rigidly specified and controlled.
The manufacture of the principal products in which industrial pitches are used are briefly described. In addition, the requirements for the pitches used in these products are given. Empirical tests that can vary in their procedure and thus produce variable results are now used to determine the commonly specified properties. A uniform code of nomenclature and evaluation procedures is needed to permit industry-wide standardization in specification writing.