Pigments special-effect

Dow Coming Z-6070 Silane pigment, special effect paints... 

Colorants have been developed for special effects. Pearlescent or iridescent give an attractive appearance. They are often used for coating paper (e.g., cosmetic packaging). The pigment consists of thin platelets, less than 1 pm thickness, which have a high refractive index, e.g., mica coated with Ti02. 

This chapter deals with pigments that produce special effects magnetic pigments (Section 5.1), anticorrosive pigments (Section 5.2), luster pigments (Section 5.3), transparent pigments (Section 5.4), and luminescent pigments (Section 5.5). 

Fluorescent and afterglow products are used to attain special effects in cinema films, on the stage, and in works of art. These effect pigments are physiologically harmless phosphors, mainly based on zinc sulfides. 

For the end user the appearance of the pigment is of interest as well as how it handles under specific conditions. For this reason for many years a variety of versions have been available that combine ease and safety of handling. Lately product cost has become more influential than in the past when selecting supply forms. However, special effects also play a very strong role which often makes cost secondary if it means gaining a market advantage. 

R. Glausch, M. Kieser, R. Maisch, G. Pfaff and J. Weitzel, Special Effect Pigments , Vincentz Verlag, Hannover, Germany, 1998. 

Colorant A pigment, dye, or other chemical that imparts color (including black and white) or any special effect appearance to a polymer. These special appearances could be metallic, pearlescent, stone and fleck, flourescent, phosphorescent, thermochromatic, or photochromatic. 

Bismuth-containing special effect pigments based on platelet-shaped crystals of bismuth oxide chloride (bismuth oxychloride, BiOCl) have been known for a long time (see Section 5.3.1.3). 

Special effect pigments, which can be natural or synthetic, show outstanding qualities of luster, brilliance and iridescent color effects based upon optically thin layers [5.122-5.125]. This visual impression develops by reflection and scattering of light on thin multiple layers. In nature this is not limited to pearls and mussel shells alone there are a multitude of birds, fish, precious stones and minerals, even insects, that... 

The total market for effect pigments can be estimated to be about 50,000 tons per year. Half of this amount can be calculated to be special effect pigments, the other half to be metal effect pigments. 

Special effect pigments suitable for outdoor applications must meet the highest standards for color fastness and weather resistance. These pigments are coated additionally with thin layers of transparent and colorless oxidic compounds. These layers increase the light resistance by reducing the photoactivity of the titanium dioxide surface. In addition, the interaction between pigment and binder is optimized. 

Special effect pigments are used as colorants or part of color formulations for all systems where traditional pigments are applied, but where additional color depth, brilliance, iridescence, color travel, and other spectacular effects are required [5.122, 5.123]. Mica-based pigments dominate their combination of pearl and interference effects, brilliance, stability and behavior in different application systems is as yet unsurpassed. Pearl luster pigments require transparent or at least translucent binders. Formulations with absorption pigments have to take their transparency and color mixing rules into account... 

Today, special effect pigments are a standard component of solvent and water-based automotive and industrial coatings. The main reasons are both the decorative effect and the technical quality. The automotive designer has a wide range of color and composition possibilities at his disposal. Attractive and individual paint is provided not only by the various colors of special effect pigments, but also by using different particle sizes in combination with other absorption pigments [5.122, 5.137, 5.161]. 

Industrial paint applications for special effect pigments are e.g. furniture, bicycles, airplanes, rail wagons, cans and containers, building exteriors, interior decoration, artificial pearls and jewelry. The main reasons for their use are the achievable special effects, the attractiveness of the colors and the good application behavior [5.122]. 

Cosmetic applications require specific effect pigments that are approved for use according to cosmetic regulations. The applications of these pigments include color cosmetics (lipsticks, eyeshadows, blushers, eye pencils, make-up, mascaras, nail lacquers), personal care products (shampoos, body washes, lotions, creams, oral care products, hair gels), and special effect items (theatrical and costume make-up, temporary hair color sprays) [5.164]. 

Glausch, R., Kieser, M., Maisch, R., Peaee, G., Weitzel, J., Special Effect Pigments, Vincentz Verlag, Hannover, 1998... 

Special effect pigments based on mica are regarded as toxicologically harmless. Their economic importance has arisen steadily production amounted to ca. 15 000 t in 1996. 

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