Pigmented materials

All paints consist of a binder (sometimes called a medium) and pigment. Materials consisting of binder only are called varnishes. Most paints and varnishes contain solvent in order to make the binder sufficiently liquid to be applied. The combination of binder and solvent is called the vehicle. Some paints are available without solvent (e.g. solventless epoxies) but these generally require special methods of application (e.g. application of heat) to reduce the viscosity. 

Thin coatings These pigmented materials, commonly known as floor paints, are often based on chlorinated rubber (see Section 12.3.2) or epoxy ester (see Section 12.3.1). They have limited life in heavy traffic but are easy to apply. 

Adsorption column chromatography has been employed to separate the constituents of pyrethrum. Florisil and aluminum oxide have been used as adsorption columns to retain much of the pigmented materials. The pyrethroids may be caused to elute with several solvents. In our experience mixtures of hexane with ethyl acetate, methanol, ethyl ether, dichloromethane, or acetone have provided different elution patterns. 

Generic fulvic acid Pigmented material in the fulvic acid fraction... 

X-rays can easily determine the presence of PVC via the chlorine atom. Single wavelength infrared is used to separate clear (PET and PVC), translucent (HDPE and PP), and opaque (all pigmented materials and colored HDPE) streams. Full-spectrum infrared can detect differences in... 

Colour technologists actually use three visual characteristics to describe the general characteristics of dyed or pigmented materials ... 

On the basis of an interlaboratory test of die method using viscous, heavily-pigmented materials which tended to form a surface film, the within-laboratory standard deviation was found to be 3F(1-7C) and the between-laboratory standard deviation was found to be 7 F(3-9C). Based on these standard deviations, the following criteria should be used for judging the acceptability of results at a 95% confidence level ... 

The correlation of line-broadening with the chemical conditions of preparation of materials also falls within our scope. Consider, for instance, pigment materials we are not concerned with the colour or other physical properties as such but the colour of a powder may depend not only on the crystal structure of the particles, but also orv their size and the size may depend on the chemical conditions of preparation. 

Evaluation of Color Changes (see Section 1.3.2). Color changes are differences in lightness, chroma, and hue such as exist between identical samples with different histories. Evaluation methods are particularly suitable for the determination and evaluation of color changes that occur following physical and chemical stresses on pigmented materials. The CIE tristimulus values X, Y, and Z of the samples or of different test locations on a sample are determined with a colorimeter. The CIELAB... 

However, the ground can be added to the support in preparation for the addition of pigmented material. 

Clapp TC, Umbreit TH, Meeker RJ, et al. 1991. Bioavailability of lead and chromium from encapsulated pigment materials. Bull Environ Contam Toxicol 46 271-275. 

Surface energy relationships between pigment materials and rubber." Ind. Eng. Chem, 26 1187-1190. 

Polymeric color is a term that has been recognized in the wine industries for many years. Condensation of anthocyanins and proanthocyanidins may contribute to the formation of polymeric color, although the structural characterization of the compounds that contribute to polymeric color are poorly defined. Studies using electrospray mass spectrometric analysis demonstrated the presence of pigmented material from grape skins that was chiefiy composed of direct condensation products of anthocyanins extending up to trimers (Vidal et al., 2004). Recent studies have evaluated the effects of processing of blueberries. 

Bleaching. The refined oils are usually dark in color owing to the presence of some pigmented materials such as chlorophyll or carotenoids and minor impurities like residual phosphatides, soaps, metals, and oxi-datin products. Bleaching reduces the color by absorbing these colorants on bleaching earth (bentonite clays), or activated charcoal, or both. In addition to decolorization, bleaching clay also absorbs suspended matter and other minor impurities. 

Some materials, by either their physicochemical or their toxicological natures, generate difficulties in the performance and evaluation of dermal irritation tests. The most commonly encountered of these problems are due to compound volatility, pigmented material, and systemic toxicity. 

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