30 декабря, 2015 
Pokraskin These pigments, also termed core pigments, such as phosphate silicates (see Section 5.2.5.3), consist of a complex composite of alkaline earth silicates, like calcium silicate. Available commercial grades differ primarily in their B2O3-content and oil absorption value (Table 5.9) [5.53].
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Tab. 5.9: Typical properties of calcium borate silicates [5.53].
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They are mainly recommended for application in protective coatings based on solvent-borne alkyd resins [5.83].
5.2.7.2
Barium Metaborates
Commercially available pigments are characterized as modified barium metaborates. In this case, the meaning of the term modified is a silicon modification, which is used to reduce the solubility of the barium metaborate. Unmodified barium metaborates would not be suitable as pigments due to their high solubility [5.55]. Barium metaborate pigments can be produced by precipitation of a mixture of barium sulfide (BaS) and borax (Na2B4O7 • 5H2O) in the presence of sodium silicate (Na2SiO3) [5.90]. Modified barium metaborates have a neutral white color and are mainly recommended for use in industrial solvent-borne coatings [5.55].
5.2.8
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