C.I. Acid Red

Behnajady, M.A., Modirshahla, N., Daneshvar, N. and Rabbani, M. (2007) Photocatalytic degradation of C.I. Acid Red 27 by immobilized ZnO on glass plates in continuous-mode. Journal of Hazardous materials, 140, 257-263. 

Ibrahim et al. [30] described a fluorimetric method for the determination primaquine and two other aminoquinoline antimalarial drugs using eosin. Powdered tablets or ampule contents containing the equivalent of 50 mg of the drug was extracted with or dissolved in water (100 mL). A 10 mL aliquot was mixed with 10 mL of aqueous ammonia, 1 mL of 0.001% eosin (C.I. acid red 87) in dichloro-ethane, and dichloroethane was added to volume. Primaquine was determined fluorimetrically at 450 nm (excitation at 368 nm). Calibration graphs were rectilinear for 0.1-5 pg/mL of primaquine. Recoveries were quantitative. The method could be readily adapted for determination of the drug in biological fluids. 

Khehra MS, Saini HS, Sharma DK (2006) Biodegradation of azo dye C.I. Acid Red 88 by an anoxic-aerobic sequential bioreactor. Dyes Pigm 70 1-7... 

The C.I. (Colour Index) name for a dye is derived from the application class to which the dye belongs, the color or hue of the dye and a sequential number, e.g., C.I. Acid Yellow 3, C.I. Acid Red 266, C.I. Basic Blue 41, and C.I. Vat Black 7. A five digit C.I. (Constitution) number is assigned to a dye when its chemical structure has been disclosed by the manufacturer. The following example illustrates these points ... 

Naphthols and Naphtholsulfonic Acids as Coupling Components. This series includes two important acid dyes with very similar structures C.I. Acid Red 88 (see Section 3.9.3), derived from diazotized naphthionic acid and 2-naphthol, and C.I. Acid Red 13, 16045 [2302-96-7] (2), from naphthionic acid and Schaffer s acid. Both are all-purpose dyes which, because of their attractive red shades, are still in use today in many areas of textile dyeing and also for leather and paper dyes. Wool dyeings produced with these dyes exhibit moderate fastness levels. 

A previously much used red wool dye is C.I. Acid Red 14 (see Section 3.9.3), which is now used to a limited extent in wool dyeing for inexpensive articles. 

Further examples are C.I. Acid Red 32, 17065 (8) [6360-10-7], and C.I. Acid Blue 117, 17055 [10169-12-7] (9). On wool both dyes exhibit quite good wetfastness and high leveling power. 

To achieve valuable dyes with alkaline coupling to y acid, the amino group must be acylated or arylated. Example C.I. Acid Red 68, 17920 [6369-40-0] (10). On wool it exhibits high leveling power and yields light- and wetfast dyeings. 

An interesting development is achieved by incorporating long hydrophobic hydrocarbon radicals, which yields dyes with neutral affinity to wool and very good wetfastness properties [6], Example C.I. Acid Red 138, 18073 [15792-43-5] (13) ... 

Dyes based on these compounds possess, in addition to good lightfastness, excellent wetfastness and are usually neutral-dyeing on wool. This, although of no importance for dyeing pure wool, plays an important role in dyeing blended spun yam and blended fabrics of wool and cotton or wool and viscose staple. The neutral-dyeing acid dye can be used in combination with direct dyes (union wool recipes). Examples are C.I. Acid Yellow 56, 24825 [6548-24-9] (17), and C.I. Acid Red 154, 24800 [6507-79-5] (18 R = CH3). 

The main area of application for the acid polyamide dyes of group A is in carpet dyeing, but they are also used in other areas of textile dyeing where the fastness requirements are not too stringent. A few structures are presented below to illustrate the types of azo dyes used C.I. Acid Yellow25, 18835 [6359-85-9] (31), C.I. Acid Red 42, 17070 [6245-60-9] (32), C.I. Acid Red 32, 17065 [6360-10-7] (33). 

Yellow, red, and navy blue for leather can be obtained with monoazo dyes. Generally speaking, azo dyes with naphthalene moieties give deeper shades than those with phenyl residues. These classical acid dyes were developed for wool, silk, and polyamide fibers, and suitable ranges are applied to leather. The molecular weight for penetration dyes is below 500. Typical leather penetration dyes are C.I. Acid Yellow 11 18820 [6359-82-6] (7) and C.I. Acid Red 7, 14895 [5 5 -61-7] (8 Orange II), which are still used today. 

C.I. Acid Blue 138 and C.I. Acid Red 138. Because it is well known that azo dyes derived from naphthol and pyrazolone intermediates exist predominantly in the hydra-zone form, this tautomeric form is given for Acid Yellow 42, Acid Red 151, Acid Red 138, and for the appropriate dyes that follow in this chapter. 

Like phenolphthalein, xanthene dyes are prepared in a condensation reaction involving phthalic anhydride. However, resorcinol is employed instead of phenol. The simplest representative of this family is C.I. Acid Yellow 73 (fluorescein), which is made via the sequence of steps shown in Fig. 13.109. Similarly, C.I. Acid Red 92 is made by the condensation of tetrachlorophthalic anhydride and resorcinol followed by bromination. 

W4 Red H2Or si. sol, C2H5OH insol. cone. CH3COOH si. sol. cone. NH3 soln. yellow, fiber colorless + C2H5OH pale red cone. H2S04 soln. red-violet, fiber dark red + H20 soln. si. yellow, fiber bright red. Indicative of Ponceau RR (C. I. Acid Red 26)... 

Wll Red H20 n.r. C2H5OH soln. pink, fiber, n.r. cone. CH3COOH n.r. cone. NH3 sol. pink, fiber colorless + cone. CH3COOH Sol. colorless, fiber colorless Indicative of Fast Red AV (C. I. Acid Red 88)... 

SYNS AIZEN ACID PHLOXINE PB C.I. 45410 C.I. ACID RED 92 CYANOSIN CYANOSIN (ACID DYE)... 

SYNS C.1.13020 C.I. ACID RED 2 p-piMETHYLAMINO)AZOBENZENE-o-CARBOXYLIC ACID 4 -DIMETHYLAMIN0AZ0BENZENE-2-CARBOXYLIC ACID o-((p-(DIMETHYLAMINO)-PHENYL)AZ0)BENZ0IC ACID 2-((4-DIMETHYL-AiMINO)PHENYLAZO)BENZOIC ACID METHYL RED... 

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