Pigment Blacks

Function Black pigmentation, high absorption of light 

Properties affected Colour carbon black also has useful anti-static properties, can provide electrical conductivity black pigments also give effective UV screening also used as a reinforcement in rubber compounds (the largest overall use) 

Materials/characteristics Carbon black different types according to manufacturing process, giving a wide range of particle sizes and shapes, governing the application. Black antimony sulphide is interesting as it is also a flame retardant 

Disadvantages High potential to contaminate other materials/equipment unless kept separate or used in dust-free/non-polluting form 

New developments improvement in stability, dispersabllity forms for easier use/faster mixing large use ofmasterbatch forms 

A number of chemical elements, mainly oxygen and carbon but also others, such as tin, phosphorus, and sulfur, occur naturally in more than one form. The various forms differ from one another in their physical properties and also, less frequently, in some of their chemical properties. The characteristic of some elements to exist in two or more modifications is known as allotropy, and the different modifications of each element are known as Its attotropes. The phenomenon of allotropy is generally attributed to dissimilarities in the way the component atoms bond to each other in each allotrope either variation in the number of atoms bonded to form a molecule, as in the allotropes oxygen and ozone, or to differences in the crystal structure of solids such as graphite and diamond, the allotropes of carbon. 

In the lower layers of the atmosphere, ozone occurs only In trace quantities. Some ozone, however, is also created In the lower atmosphere by lightning, during electric storms, accounting for the smell of rain that 

The allotropy of carbon is due to variations in the crystal structure of the element. There are three allotropes of carbon graphite, diamond, and 

Another element that exhibits allotropy because of variations in the crystal structure is tin. The common allotrope is tin metal, also known as a alpha) tin, which is stable at ambient temperatures. The other allotrope, which generally occurs as a gray powder and is known as p beta) tin, but also as tin pest, is formed only at very low temperatures when tin cools down to temperatures below -18°C, the ordinary allotrope, a tin, is converted to p tin, and the transformation is irreversible under ordinary temperatures. Tin objects exposed to temperatures below -18°C in very cold regions of the world, for example, are generally severely damaged when part of the tin converts to tin pest. In extreme cases, when exposure to low temperatures extends for long periods of time, the allotropic conversion may result in the transformation of tin objects into heaps of gray p-tin powder. 

Black pigments of vegetable origin have generally been made from various kinds of charred plant matter, mostly wood, but also leaves or seeds the charcoal formed during the charring process is then washed, to remove soluble matter, and finally ground to powder. Over 95% of well-burned char- 

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Black Pigments. The only black pigment used to an appreciable extent in inks is carbon black It is used in newsprinting, pubHcation, commercial and packaging printing therefore, in large quantities. Black pigments ate offered in fluffy or beaded forms and in a variety of particle sizes and physical properties. 

Pyrrole oxidizes in air to red or black pigments of uncertain composition. More usehil is the preparation of 2-oxo-A -pyrrolines, which is best carried out by oxidation of the appropriate pyrrole with in pyridine (37), eg, 3,5-dimethyl-ethyl-3-pyrrolin-2-one [4030-24-4] from... 

It is also common to distress the surface for resemblance to antique furniture. For example, spots of black pigment stain can simulate India ink spots dropped from quiH pens, and dark stains carefully appHed into corners simulate dirt accumulated over many years. When this "art work" is completed, a sanding sealer is appHed to immobilize the lower layers of the finish and to provide a surface that can be sanded smooth. Finally a top coat is appHed and poHshed smooth. 

Grayness of a fabric swatch is not directly proportional to its content of black pigment (or artificial sod). A basic formula relating reflectance to the pigment content or concentration can be appHed to the evaluation of detergency test swatches (51,99—101). In simple form, an adaptation of the Kubelka-Munk equation, it states that the quantity (1 — i ) /2R (where R is the fraction of light reflected from the sample) is a linear function of the sod content of the sample. 

Iron. This is a specialty drier that is considered active at temperatures of about 130°C. For this reason iron 2-ethyIhexanoate [19583-54-1] is used in bake coatings that require maximum hardness. The principal drawback of using iron driers is that iron contributes a characteristic brownish red color to the coating and should only be used in dark pigmented systems. It has been reported that iron aids the dispersion of carbon black pigment and reduces the tendency for orange peel film defects (6). 

Carbon black dominates as black pigment. It is a petrochemical made from natural gas or petroleum residues by incomplete combustion - cooking to split the hydrocarbon into hydrogen and carbon. Its primary use is in compounding rubber for making tires of which an average passenger... 

Most black pigments are made of carbon black formed by depositing carbon from a smoky flame of natural gas on a metal surface. Lampblack is made similarly by burning oik Bone blacks are made from charred bones. Graphite occurs naturally or can be prepared from coal in electric furnaces. Mineral blacks come from shale, peat, and coal dust. Iron oxide blacks are found in nature or prepared. Blue lead sulfate is a pigment for priming. Of these, carbon black is su[XTinr. 

This benign autosomal recessive disorder consists of conjugated hyperbilirubinemia in childhood or during adult life. The hyperbilirubinemia is caused by mutations in the gene encoding MRP-2 (see above), the protein involved in the secretion of conjugated bilirubin into bile. The centrilobular hepatocytes contain an abnormal black pigment that may be derived from epinephrine. 

Other spherical fillers include carbon black. This has several roles particularly in combination with elastomers, e.g., black pigment, anti-oxidant and UV stabiliser, reinforcing filler, and an electrical conductor when used at 60% concentration. Wood flour is particularly effective in phenol/formaldehyde and melamine or urea/formaldehyde thermoset resins because the phenolic lignin component in the wood reacts with the methylol groups (-CH2OH) in the growing polymer. 

An early form of carbon black produced by the burning of oils in a simple type of furnace. It was used in the compounding of rubber mainly as a black pigment it has little or no reinforcing effect. 

Carbon black pigments, 19 409-410 Carbon blacks, 10 713 11 316-317 as graphite filler materials, 12 724 production of, 19 385 Carbon—carbon bond cleavage, in lignin, 15 6... 

Chrome Iron Nickel Black, pigment for plastics, 7 369t... 

Copper Chromate Black, pigment for plastics, 7 369t Copper chromite, molecular formula, properties, and uses, 6 563t Copper chromite black spinel, formula and DCMA number, 7 348t Copper citrate, molecular formula, 6V638t Copper compounds, 7 767-783 analytical methods, 7 773-776 economic aspects, 7 773 health and safety factors, 7 776 properties and manufacture, 7 768-773 uses, 7 776-780... 

Inorganic pigments, 29 375-417 black pigments, 29 408-410 chemical properties of, 29 377-378 classification of, 29 402 colored pigments, 29 397-408 crystal structure of, 29 377-378 durability of, 29 382-384 environmental aspects of, 29 413-415 lead- and cadmium-containing, 29 414-415... 

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