Pigments supply form

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. 

Because of their small particle size and their resulting large surface area, pigment blacks are classed as pigments, which are more difficult to disperse. Depending on the supplied form, pigment blacks can be dispersed with all grinding machines, for example sand mill, pearl mill, ball mill, triple roll mill and others. 

Preferred supplied forms are powders (gold bronze), pastes (aluminum) in plasticizers (like white oil, DINP etc.) and pellets in polyethylene. Due to the chemical nature of gold bronze, there are special coated pigments for use in high temperature processes (tarnish- or heat-resistant gold bronze). Also for use in PVC, special chemically resistant aluminum and gold bronze pigments are available. 

In sorghum ergot, Claviceps africana, the sclerotia were thought to be rounded, 3-5 mm in diameter, with reddish brown spots, until another population of this fungus specialized on Hyparrhenia spp. was discovered (D. Frederickson and S. Pazoutova, unpublished), whose sclerotia are cylindrical and brown to black, 2-4 mm in length, and 0.5-1 mm wide. Here, the sclerotium is shaped only by floral cavity, and even the color is influenced by the pigments supplied by the host. Sclerotia formed on sorghum cultivars with dark seeds are more... 

Corrosion control by pigments relies on well-known principles of corrosion inhibition. Iron and steel exposed to air are quickly covered by an oxide film aqueous electrolytes tend to break down this film, and further oxidation of the metal surface ensues. The role of anodic corrosion inhibitors is to supplement or to aid in the repair of the surface oxide film. Basic pigments may form soaps, for example, with linseed oil autoxidation of these soaps may yield soluble inhibitors in the film. Some other pigments of limited solubility act directly as inhibitors. Active metal pigments supply electrons to the iron substrate and thus lower its potential and prevent metal dissolution. 

Formulating Considerations Melting point 20-30°C. Add to oil phase of emulsions. Disperse in oils/waxes of pigmented products Form Supplied Semisolid wax Regulatory Status Nonhazardous... 

Within the pigments industry itself, there has been a growing realisation that the physical state of pigments is of the greatest importance to pigment users. Most suppliers now offer several products based on the same chemical structure and the physical form in which it is supplied is chosen to suit the intended application. Thus, the 1997 edition of Pigments and... 

Most plastics e.g. polyolefins and polystyrenes and their derivatives such as ABS (acrylonitrile-butadiene-styrene) and SAN (styrene-acrylonitrile) are supplied by the manufacturers in ready-to-use form with most of the above-mentioned stabilizers or simply need to be additionally stabilized with other additives, e.g. antistatic agents and HALS stabilizers, as required. On the other hand, in the case of other materials (e.g. PVC) it is the end user who adds the additives, pigments or preparations. This is normally done on fluid or high-speed mixers, although in the past gravity mixers or tumble mixers were also used. The mixture is then homogenized on mixing rolls, kneaders, planetary extruders or twin-screw kneaders and further processed. 

Polyolefins are produced in a variety of forms HDPE and PP are produced as powders, while LDPE emerges from the melt preferably in the form of lenticular granules. All types, however, are supplied primarily as granules. As a rule, any thermoplastic transformation of a polymer powder to a granulate is carried out in the presence of additives. This is also partly true for pigments. 

Pigment Red 57, discovered in 1903 by R. Gley and O. Siebert at AGFA, developed into one of the most important organic pigments in the market. It was first supplied in the form of its yellowish red sodium salt, to be converted to the calcium or barium salt by the consumer. 

The main field of application for P.R.48 1 is in printing inks and plastics. In order to enhance the transparency in print and to reduce the strong tendency of the prints to bronze, pigments that are targeted for use in printing inks are frequently supplied in resinated form. 

In the presence of a solvent, the crude pigment generally evolves in much purer form than if it is prepared by baking. Higher degrees of purity, i.e., up to 98%, are achieved by additional alkaline and/or acidic treatment. Commercially available types of crude Copper Phthalocyanine Blue typically contain more than 90% pure pigment. This preliminary product is also commonly supplied to and finished by companies who do not manufacture crude pigment themselves. 

The a- and (i-types of Copper Phthalocyanine Blue reign supreme among commercially available phthalocyanine pigments. There is also an increasing amount of interest in the phase-stabilized form of the a-crystal modification. Both modifications are also supplied as flocculation resistant types. 

In Europe, Copper Phthalocyanine Blue is usually supplied as a powder or as a granulate. The granulated product is somewhat less dusty but also more difficult to disperse. In the USA, P.B.15 3 also continues to be offered in the form of flushed pastes to be incorporated into oil-based printing inks. These pastes offer improved pigment dispersion and frequently afford more glossy and transparent prints. 

Dichloroisoviolanthrone was supplied by the pigment industry in the form of a pigment preparation, which was a specialty product for use in spin dyed viscose fibers. This pigment preparation has only recently been withdrawn from the market. The shade of P.V.31 is a reddish violet, which is distinctly redder than that of the known... 

P.Br.22 is offered in the form of a variety of pigment preparations, designed for industrial finishes, packaging gravure printing inks, or wood stains. The pigment is not supplied as a powder. 

Paprika contains capsombin and capsanthin (Fig. 8.3) which occur mainly as the lauric acid esters, and about 20 other carotenoid pigments. Paprika is produced in many countries which have developed their own specialties. Cayenne or cayenne pepper, produced from a different cultivar of C. annum, is usually more pungent. C. frutescens is the source of the very pungent Tabasco sauce. Paprika oleoresin is produced by solvent extraction of the ground powder. Obviously paprika supplies both flavor and color and its use is limited to those products compatible with the flavor. The recent rise in demand for tomato products in the form of pizza, salsa, etc., has increased the demand for paprika. Paprika is used in meat products, soups, sauces, salad dressings, processed cheese, snacks, confectionery and baked goods.1018... 

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