Auxiliary pigments

Emerson, R., and Rabinowitch, E. 1960. Red drop and role of auxiliary pigments in photosynthesis. Plant Physiol. 35 477 185. 

B. Accessory (or auxiliary) pigments, presumably carotenoids, which are isopre-noids. 

Use Anticorrosive pigment for solvent-based epoxies and as auxiliary pigment for 1-package zinc-rich coatings. Also used in water-based coatings. 

Uses Pigment wetting and dispersing agent detergent emulsifier and acid cleaner additive for metals textile antistatic agent, softener, and auxiliary pigment dispersant for paints filler dispersant in rubber Properties Lt. brn. solid in winter, liq. in summer amine no. 80 5 cloud pt. 95 C min. 

Absorbance spectra of extracts from Synechoooccus (not shown) indicate the presence of large amounts of the auxiliary pigment allophyoocyanin (APC). From peak values at 655 nm and at 675 nm we estimate a molar ratio of 3 Oil/APC. Together with the results from table I one obtains the ratio Chl-ajj (P680) Chl APC = 1 100 33. Hierefore/ we conclude that an almost complete jAiyoobiliscme core is attached to the PS II complex. 

The initial objective of this series of books has been to establish a coherent body of explanatory information on the principles and application technology of relevance for students preparing to take the Associateship examinations of the Society. This particular book has been directed specifically to the subject areas covered by Section A of Paper B the organic chemistry and application of dyes and pigments and of the auxiliaries used with them in textile coloration processes. However, many qualified chemists and colourists interested in the properties of colorants and their auxiliaries have found the First Edition useful as a work of reference. For several reasons it has been convenient to divide the material into two separate volumes 1. Colorants, 2. Auxiliaries. Although fluorescent brighteners share some features in common with colorants, they have been treated as auxiliary products in this book. 

Another example is the influence of the electrical resistance of PVC cable insulation. This is caused not by the organic pigment itself but by ethoxylated surfactants, which are added as auxiliaries in the manufacture of these pigments, especially azo pigments. Contrary to a repeatedly expressed view, a possible electrolyte content, which laked azo pigments for example can have, has no effect on the dielectric properties of PVC [34]. Some pigment manufacturers offer special product ranges with verified dielectric properties for this purpose. 

Opaque perylene pigment varieties are treated in ball mills, either in the presence or absence of milling auxiliaries. The pigments are typically heated to 80 to 150°C in solvents such as methyl ethyl ketone, isobutanol, diethylene glycol, N-methylpyrrolidone, possibly in the presence of water. 

Publications summarizing the results of studies on the effect of pigments on the skin and mucous membrane (conjunctiva of eyes) of rabbits describe similar observations. These sources refer to pigments as trade products which may contain auxiliaries (Table 37). 

Size-exclusion chromatography combined with RP-HPLC-MS was employed for the separation of pyranoanthocyanins from red wine. Wine samples (10 ml) were acidified with 3 M HC1 to pH 1 then sodium bisulphite was added at a concentration of 400 g/1. After 15 min reaction time the treated wine was loaded into a gel column (200 X 15 mm i.d.). Pigments were eluted with 95 per cent ethanol followed with 100 per cent methanol. The various fractions were acidified to pH 1, concentrated and redissolved in water. HPLC-DAD was carried out in an ODS column (150 X 4.6 mm i.d. particle size 5 /nn) at 35°C. Solvents were 0.1 per cent aqueous TFA (A) and ACN (B). The gradient started with 10 per cent B for 5 min to 15 per cent B for 15 min isocratic for 5 min to 18 per cent B for 5 min to 35 per cent B for 20 min. The flow rate was 0.5 ml/min and analytes were detected at 520 nm. MS conditions were sheath and auxiliary gas were a mixture of nitrogen and... 

Table 41 Application of the H-point standard addition method to a mixture of a commercial madder pigment (Kremer, 0.03325 g) plus silica (0.25836 g) and moiin (0.02486 g), this last acting as an auxiliary reference compound... 

The chemicals used for coating and laminating are polymeric materials, either naturally occurring or produced synthetically. These include natural and synthetic rubbers, polyvinyl chloride, polyvinyl alcohol, acrylic, phenohc resins, polyurethanes, silicones, fluorochemicals, epoxy resins and polyesters." Coating formulations typically include auxiliaries such as plasticizers, adhesion promoters, viscosity regulators, pigments, fillers, flame retardants, catalysts and the like. ... 

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