Лако-красочные материалы — производство

Ultramarine pigments can be used in inks for most printing processes including hot-foil stamping. Letterpress, flexography and gravure need high-strength grades; lithography needs water-repellent grades; any grade is suitable for screen inks, fabric printing and hot-foil stamping. Improved strength grades presented in a high solids aqueous dispersion are finding increasing use in flexographic printing applications […]

Ultramarine pigments are used in decorative paints, stoving finishes, transparent lac­quers, industrial paints, and powder coatings. The transparent nature of the pigment leads to some impressive flamboyant coatings in combination with effect pigments such as mica [3.166]. 3.5.4.3

Blue ultramarine can be used in any polymer; violet ultramarine has a maximum processing temperature of 280 °C, and pink ultramarine has a maximum process­ing temperature of 220 °C. With PVC, acid-resistant grades are commonly used ifcolor fades during processing. Surface-treated grades are available for enhanced dispersibility. Ultramarines do not cause shrinkage or warping of […]

The stability and safety of ultramarine pigments are the basis of their wide range of applications, which include the following: — Plastics — Paints and powder coatings — Printing inks — Paper and paper coatings — Rubber and thermoplastic elastomers — Latex products — Detergents — Cosmetics and soaps — Artists’ colors — Toys and […]

The purification and refinement operations can be batch or continuous. The raw blue is crushed and ground, slurried in warm water, then filtered and washed to remove the sulfoxides. Reslurrying and wet grinding release the sulfurous impurities and reduce the ultramarine particle size, often to 0.1-10.0 gm. The impurities are floated off by boiling or […]

The furnace is allowed to cool to 500 °C when air is admitted in controlled amounts. The oxygen reacts with excess sulfur to form sulfur dioxide, which exothermically oxidizes the di — and triatomic polysulfide ions to S2- and S3- free radicals, leaving sodium sulfoxides and sulfur as by-products. When oxidation is complete, the furnace […]

The activated clay is blended with the other raw materials and dry-ground, usually in batch or continuous ball mills, to a mean size approaching 15 pm. Typical recipes (in wt.%) are: Green Shade Red Shade Calcined clay 32.0 30.0 Feldspar 7.0 Sodium carbonate 29.0 27.0 Sulfur 34.5 33.0 Reducing agent 4.5 3.0 The ground mixture […]

Ultramarine is made from simple, relatively cheap materials, typically china clay, feldspar, anhydrous sodium carbonate, sulfur, and a reducing agent (oil, pitch, coal etc.). 3.5.3.1 Clay Activation The transformation of kaolinite to metakaolinite is brought about by heating the clay to about 700 °C causing hydroxyl ions to be removed as water. The rate of […]

The basic ultramarine color is a rich, bright reddish blue, the red-green tone vary­ing with chemical composition. The violet and pink derivatives have weaker, less saturated colors (see Figures 3.15-3.17 for reflectance spectra). The color quality of commercial pigments is developed by grinding to reduce particle size and thus enhance tinting strength. Mean particle size […]

Reviews of work on the structure of ultramarine are given in Refs. [3.154-3.156]. Ultramarine is essentially a three-dimensional aluminosilicate lattice with entrapped sodium ions and ionic sulfur groups. A simplified structure is shown in Figure 3.14. The lattice has the sodalite structure with a cubic unit cell dimension of 9.10 A [3.157]. In synthetic ultramarine […]