Colour mixtures

Physical properties of Fullerene Cyg It does not melt below 360°, and starts to sublime at 350° in vacuo. A reddish-brown solid, greenish black in thicker films. Solns are port-wine red in colour. Mixtures of Csq and C70 are red due to C70 being more intensely coloured. It is less soluble than Cso in but also dissolves... 

A colour mixture containing the 3 components ignited spontaneously. Oxidation products in the air-blown oil may have reacted exothermally with the complex cyanide, a reducant. 

Oxidation of phenol with chromic acid produces a conjugated dlketone known as benzoquinone. In the presence of air, phenols are slowly oxidised to dark coloured mixtures containing quinones. 

The mass is now introduced into a metal retort (made of iron or copper), which is connected with a long condenser tube. The retort must not be filled more than two-thirds full. It is heated over a powerful gas burner, so that the dry distillation of the salt proceeds as quickly as possible. A pale brownish coloured mixture of benzene, benzophenone and aromatic products first distils over. The distillation is stopped when the distillate becomes brown and viscous. The distillate is dried with calcium chloride, and then fractionated. The fraction 250°—310° contains the benzophenone. The product sometimes solidifies quickly, but more frequently remains syrupy for days. Crystallisation begins, however, at once, when a small quantity of solid benzophenone is added. The crystals are freed from the oily mother liquor by pressing between filter paper, or by spreading on a porous tile, and are recrystallised from ligroin. 

Attach the bromotrifluoroethylene cylinder to the condenser with rubber tubing and condense approx. 20 g <0.1 mol) of the bromotrifluoroethylene into the reaction flask. Stir the mixture at room temperature until the reaction initiates, as evidenced by an exotherm and formation of a dark brown coloured mixture. If initiation does not occur within 1 h at room temperature, warm the flask gently to 50-60°C with a heat gun to initiate metallation. 

The composition and quantity of each substance of an ingredient consisting of a mixture of substances (e.g., as in coatings, syrups, colour mixtures). 

The following formulae have been found upon actual trial to yield satisfactory green and red colour mixtures respectively ( . G. Clayton)... 

Occasionally during the assay of a medicinal product, excipients present in the formulation mask the absorbance of the active drug. This often occurs in liquid formulations such as syrups and linctuses where a small amount of a highly coloured dye is used to colour the mixture. If a simple dilution of a coloured mixture was carried out, the resulting absorbance measurements would not obey Beer s law and a non-linear graph of absorbance vs concentration would result. 

Of the above product, 18.3 g (30 mmol) is carefully ground and suspended in acetone (95 mL). The suspension is vigorously stirred at -15°C while Cu powder (11.5 g, 180 mmol) is added over 40 min (the temperature must not exceed -10°C). The mixture is stirred for a further 20 min and is then allowed to warm at 20°C. The dark-coloured mixture is filtered to remove CuCl, the filter cake is washed with acetone and the filtrate and washings are combined. The acetone solution is warmed at 20°C until a grey precipitate forms. The precipitate is collected and extracted repeatedly with boiling toluene. Activated charcoal is added to the toluene extracts, the mixture is heated at reflux and filtered and most of the toluene is distilled from the filtrate. Petroleum ether is added to precipitate the product (p-MeOCgH4)2TeCl2, which is recrystallized from benzene (6.8 g (52%) m.p. 182°C). 

COHEN J B (1988) Colour and colour mixture Scalar and vector fundamentals. 

As mentioned previously, the difficulties in obtaining colourable blends from bitumen mixtures have forced the research and production of synthetic substances which are easily colourable, with mechanical properties similar to those of bitumen, allowing their use in most applications where coloured mixtures are advised. These products, known as binders or light synthetic binders, because of their light tones, are a mixture of substances that form a macroscopically compatible system. The colouring is easy and with 1-2% w/w pigment, colour shades are obtained which meet most of the desired colour range [5]. 

Klingenberg, A. Method for manufacturing a colour mixture for use in food products, pharmaceuticals and cosmetics, and colour mixture obtained according to this method. U.S. Pat. Appl. Publ. US 2005084462, 2005 Chem. Abstr. 2005,142, 379428. 

These colorants are nsed to colour mixtures in lotions, perfumes, emulsions, soaps and bath products, where a covering effect is not necessary. These are molecules which contain one or more water-solnble groups such as sulfonic (-SO3 Na" ) or carboxylic ( COO NaO moieties. 

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