Color effects

Color Matching. Color matching is a process in which a technician prepares a formulation, ie, a mixture of pigments in a desired medium, that has the color effects desired by the customer. A good color match in one medium, eg, plastic, is not always a good match in another medium, eg, ceramic glaze. Thus the medium as well as the processing conditions have to be identical to those used by the customer. 

The color and effect produced by NGR stains and any stain mixture depend on several factors other than the colors or type of dyes used. Those factors include strength of the mixture, the amount appHed, the type of substrate, and the solvent system used for the stain. The role of the wood stain is not to provide protection rather, the primary function of the stain is to impart color effects by accentuating grain patterns. The transparency and brightness needed to enhance the natural beauty of the wood are optimized by using dye-type stains for wood. 

Tetracalcium aluminoferrite acts as a processing aid by reducing the clinkering temperature. It hydrates rapidly but does Htde for any performance property of the cured concrete. It does, however, cause most of the color effects in the cured concrete. 

Colorants can only be used ia those medical devices cited. Colorants without specific restrictions regarding quantity can be used ia amounts not to exceed the minimum reasonably required to accomplish the iatended coloring effect. 

Colorability is another reason IDs select plastics for many products. Molding color into a product eliminates finishing and painting operations, thus reducing costs. Beyond cost, integral color also masks the nicks, chips and scratches that impair appearance during the life of the product. Color effects are almost limitless. Transparent, translucent, pearlescent, fluorescent, or marbleized colors are readily available for use in plastics. 

Figure 12,4.1 The multiple reflection of light from microscopic oxide layers of different dimensions leads to constructive and destructive interference of light waves, producing a particular color effect. Different thicknesses reflect different colors.

The red colorizing effects of RIF on urine, other secretions, and contact lenses should be discussed with the patient. 

Because coloristic assessments are essentially judgments of color effects, coloristic practice long rested solely on the colorist s trained eye. Today, the measurement of color is a mature field of science, and colorists employ theories of the optical behavior of pigmented layers. 

MicroChannel plate photomultipliers are preferred to standard photomultipliers, but they are much more expensive. They exhibit faster time responses (10- to 20-fold faster) and do not show a significant color effect (see below). 

Dependence of the instrument response on wavelength. Color effect... 

When normal photomultipliers that exhibit a color effect (see above) are used, the compounds of Table 6.2 that have a short lifetime (e.g. POPOP, PPO) can be used in place of a scattering solution in order to remove this effect (this method is valid for both pulse and phase fluorometries). Such a reference fluorophore must... 

Liquid crystals are mainly used for decorative purposes in cosmetics. Cholesteric liquid crystals are particularly suitable because of their iridescent color effects, and find applications in nail varnish, eye shadow, and lipsticks. The structure of these thermotropic liquid crystals changes as a result of body temperature, resulting in the desired color effect. In recent times, such thermotropic cholesteric liquid crystals have been included in body care cosmetics, where they are dispersed in a hydrogel. Depending whether this dispersion requires stirring or a special spraying process, the iridescent liquid crystalline particles are distributed statistically in the gel (Estee Lau-... 

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