Black dye

TuU Chemical Co. (Oxford, Alabama) is the only producer of sodium fluoroacetate. It is sometimes colored with the black dye nigrosine. It is usually packed in 8 oz (227 g) or 5 kg cans and is almost exclusively exported. There is very limited use in the United States. 

Tendering Effects. CeUulosic materials dyed with sulfur black have been known to suffer degradation by acid tendering when stored under moist warm conditions. This effect may result from the Hberation of small quantities of sulfuric acid which occurs when some of the polysulfide links of the sulfur dye are mptured. A buffer, such as sodium acetate, or a dilute alkaH in the final rinse, especially after oxidation in acidic conditions, may prevent this occurrence. Copper salts should never be used with sulfur black dyes because they cataly2e sulfuric acid generation. Few instances of tendering with sulfur dyes other than black occur and the problem is largely confined to cotton. 

Minor uses of vanadium chemicals are preparation of vanadium metal from refined pentoxide or vanadium tetrachloride Hquid-phase organic oxidation reactions, eg, production of aniline black dyes for textile use and printing inks color modifiers in mercury-vapor lamps vanadyl fatty acids as driers in paints and varnish and ammonium or sodium vanadates as corrosion inhibitors in flue-gas scmbbers. 

Blown and black dyes are generally disazo with exceptions for metallized or polycyclic stmctuies (7). Two disazo dyes are Reactive Brown 11 [70161-17-0] (26) and Reactive Black 5 [17095-24-8] Cl 20505) (27). 

Methyl-l-phenyl-3-pyrazolin-5-one gives a green-black dye (736) with 4-nitroso- or 4-amino-dimethylaniline and silver chlorides in the presence of light, a process of great importance in colour photography (B-76MI40403). 

Ferrous gluconate is a black dye. It is composed of iron bound to two molecules of gluconic acid, which is the acid form of glucose. 

Ferrous gluconate is the black dye used to color ripe olives. It is also used as an iron supplement to treat iron-deficiency anemia. 

For environmental reasons, other attempts have been made to reduce the amount of conventional electrolyte added. Lowering the liquor ratio will in itself reduce the amount of electrolyte required. In one commercially feasible system [72], a range of direct dyes was successfully screened to select members that could be applied efficiently to give 95-100% exhaustion using significantly less electrolyte than usual. Thus at applied depths up to 2-3%, only 2-5 g/1 salt is required navy and black dyeings can be produced with only 7.5-10 g/1 salt compared with the conventional 25 g/1 addition. 

Various methods have been used for the reoxidation of vat leuco dyeings atmospheric skying, hypochlorite, chlorite and acidified dichromate are now rarely employed. Atmospheric oxidation can be difficult to control and thus uneven with some dyes it is also too slow, particularly for continuous methods. Sodium hypochlorite is used only for those few black dyes that tend to become dark green when oxidised with peroxide obviously hypochlorite should be avoided with the many chlorine-sensitive dyes. Similarly sodium chlorite, acidified to below pH 5 with acetic acid, can only be used with certain dyes, although with these it certainly gives rapid oxidation. Dye selectivity is also a drawback with... 

The less important positive CCAs are metal-free cationic molecules, such as the black dye nigrosine and the colorless quaternary compound cetyl pyridinium chloride.35,36... 

There have also been attempts to obtain a black phthalocyanine dye for ink jet printing. Thus, a patent47 from Nippon Kayaku describes reacting the amino phthalocyanine (59) with acrylic or methacrylic acid to produce the black dyes (60). 

Solvent-soluble metal complex azo black dyes are used in both industrial ink jet printing and hot melt ink jet printing. Cl Solvent Black 35 (61) is a typical dye.48... 

Baxter, A. G. W. Bostock, S. Greenwood, D. (ICI). Water-Soluble Phthalocyanine Black Dyes from Cellulose Reactive Groups and Suitable for Use in Inks. U.S. Patent 4,705,528, November 10,1987. 

Sectioning material for immunocytochemistry with glass and diamond knives is identical to the process used for conventional EM. One difficulty frequently encountered is that unosmicated tissue embedded in plastic is sufficiently cleared by the solvent and embedding process as to be almost invisible. This makes orientation of the tissue in the trimming of the blocks difficult and increases the chances of mistakes of cutting too much. A small amount of Sudan Black dye can be added to... 

Mordant dyes are notoriously troublesome from the viewpoint of colour matching because the hue of the chromium complex usually differs greatly from that of the unmetallised parent dye (section 5.4.1). If other metal ions are present in the treatment bath or on the fibre during chroming, the colour obtained is likely to differ from that of the pure chromium complex. Certain important chrome dyes, including Cl Mordant Black 11 (3.29) and Black 17 (3.30), are particularly sensitive to traces of iron or copper. The hue of the black dyeings obtained is redder in the presence of copper and browner with iron contamination. The fastness to light and wet treatments may also prove inferior under these conditions. Even certain 1 2 metal-complex acid dyes show similar effects in the presence of these impurities,... 

Cl Sulphur Black 1, which is produced from the relatively simple intermediate 2,4-dinitrophenol and aqueous sodium polysulphide. A similar product (Cl Sulphur Black 2) is obtained from a mixture of 2,4-dinitrophenol and either picric acid (6.148 X = N02) or picramic acid (6.148 X = NH2). A black dye possessing superior fastness to chlorine when on the fibre (Cl Sulphur Black 11) can be made from the naphthalene intermediate 6.149 by heating it in a solution of sodium polysulphide in butanol. An equivalent reaction using the carbazole intermediate 6.150 gives rise to the reddish blue Cl Vat Blue 43 (Hydron blue). This important compound, which also possesses superior fastness properties, is classified as a sulphurised vat dye because it is normally applied from an alkaline sodium dithionite bath. Interestingly, inclusion of copper(II) sulphate in the sulphurisation of intermediate 6.150 leads to the formation of the bluish black Cl Sulphur Black 4. 

TLC separation of the components of black dye commercial product (BDCP) was performed on silica layers. The chemical structures of the dye components are shown in Fig. 3.17. Dyes were extracted from the effluent of the dye processing plant, from the untreated river water and from the drinking water treatment plant. The organic extracts were further concentrated and purified using a copolymer of styrene divinyl benzene. The mobile phase for TLC separation consisted of toluene-ethyl acetate (8 1, v/v). The Rp values of dye components were 0.43 (C. I. Disperse Violet 93), 0.48 (C. I. Disperse Orange 37) and 0.59 (C. I. Disperse Blue 373), respectively. 

Reduction of Hazardous Sulfide in Effluent from Sulfur Black Dyeing at Century Textiles, Bombay, India... 

Copper(II) sulfide is used in antifouling paints in andine black dye for dyeing of fabrics and in the preparation of catalysts for organic reactions. It occurs in nature as the mineral coveUite. 

Amido black dye Two years later, Grassman and Hanning developed another organic dye to be used on filter paper after electrophoresis amido black stain. It has moderate sensitivity. Today, amido black dye is used for colorimetric determination of electroblotted proteins on PVDF (poly-vinylidene difluoride) and nitrocellulose membranes. 

Figure 5 Light absorption properties of N3 dye, black dye, and their Ti02 photoelectrodes represented by absorbance and light-harvesting efficiency.

Photovoltaic performance of the DSSC is described as follows Figure 8 shows the external spectral response curve of the photocurrent for nanocrystalline Ti02 solar cells sensitized by N3 and black dyes with the I /If redox mediator, where the incident photon-to-current conversion efficiency (IPCE) is represented as a function of wavelength. IPCE is obtained by the following equation ... 

Figure 8 Spectral responses (IPCE) of N3- and black dye-sensitized 2 solar cells. IPCE is plotted as a function of wavelength. (Data from Ref. 20.)...

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