Pigment manufacturing process

Inorganic Pigments-Manufacturing Process-Chemical Technology, Review No. 166, ed. M.H. Gutcho, Noyes Data Corporation, U.S.A. 

Water According to latest German wastewater legislation [3.142] for inorganic pigment manufacturing processes discharging directly into public streams of water, mass Umits for lead and chromium related to approved tormes of armual production... 

In a number of cases, identifications have been extremely difficult, because the materials were synthetic and knowledge of their existence had actually been lost. For example, several rather commonly encountered synthetic pigments, such as the lead-tin yellow often found in Renaissance and Baroque paintings, were originally misidentified or left unidentifiable until extensive research, including analyses of elemental composition and chemical and physical properties, and repHcation experiments, led to proper identification of the material and its manufacturing process. 

Phosphoms trichloride is also used in the manufacture of antifoam agents, catalysts, dyes and pigments, as well as pharmaceutical and quaternary compounds, and is commonly used as a chlorinating agent. Phosphoms trichloride is used to make phosphoms oxychloride, which is used in the manufacture of adsorbents for air filters, antifoam agents, dyes and pigments, mineral-processing materials, pharmaceuticals (qv), and solvents. These uses represented 32,000 t of PCl in 1988 and 30,000 t in 1994. 

In the process of testing, color deviations are expressed ia the CIELAB system which projects total color differences either on the axes of the rectangular LAB or the equivalent polar LHC system (26). In either case tested samples must fall within acceptable ranges or limits estabhshed versus a standard by the pigment manufacturer and accepted by the pigment user. 

The basic manufacturing process involves thorough blending of the components, especially the pigments, and comminution with the aid of a variety of mills to reduce the particle size. Loose powders ate filled without additional processing. 

TSR (2) [Tiomin synthetic rutile] A process for removing much of the iron from ilmenite in order to make a feedstock for titanium pigment manufacture. Developed by Tiomin Resources, Canada, in the 1990s. 

For surface energy reasons, the tendency of these small particles to agglomerate and form crystallites increases with decreasing particle size. This is particularly true for the final phase of pigment manufacture, the drying and milling processes. 

Manufacturing processes afford azo pigments with, for instance, certain defined physical forms. Thermal treatment usually increases the particle size, reduces the tinctorial strength, and may improve the hiding power of a pigment. Reversal of... 

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