Mordant red

Aminohydroxy-substituted xanthenes ate of Httle commercial importance. They are synthesized by condensing one mole of y -diaLkylaminophenol with phthahc anhydride, and then condensing that product with an appropriately substituted phenol. For example. Mordant Red 77 [6528-43 ] (Cl45300) (45) is prepared by condensing m- dim ethyl am in opb en o1 with phthaUc anhydride, and then condensing the product with 2,4-dihydroxybenzenesulfonic acid. 

Mordant Red 27 [6539-224] 45180 Brightener 74 Chromoxane 4.5 4.5 American Hoechst Corp. 

V,/V-dimethy1amino)pheno1 (177). In addition, 3-aminophenol may be methylated with dimethyl sulfate under neutral conditions, or its hydrochloride salt heated with methanol at 170°C under pressure for 8 h to give the desired product (178). The compound is used primarily as an intermediate in the production of basic (Red 3 and Red 11) and mordant (Red 77) dyes. 

In mordant dyes, phenols, naphthols, and enolizable carbonyl compounds, such as pyrazolones, are generally the couplers. As a rule, 2 1 metal complexes are formed ia the afterchroming process. A typical example of a mordant dye is Eriochrome Black T (18b) which is made from the important dyestuff iatermediate nitro-l,2,4-acid, 4-amiQO-3-hydroxy-7-nitro-l-naphthalenesulfonic acid [6259-63-8]. Eriochrome Red B [3618-63-1] (49) (Cl Mordant Red 7 Cl 18760) (1, 2,4-acid — l-phenyl-3-methyl-5-pyrazolone) is another example. The equiUbrium of the two tautomeric forms depends on the nature of the solvent. 

Mordant dyes have hydroxy groups in their molecular stmcture that are capable of forming complexes with metals. Although a variety of metals such as iron, copper, aluminum, and cobalt have been used, chromium is most preferable as a mordant. Alizarin or Cl Mordant Red 11 [72 8-0] (1) (Cl 58000), the principal component of the natural dye obtained from madder root, is the most typical mordant dye (see Dyes, natural). The aluminum mordant of alizarin is a well-known dye by the name of Turkey Red and was used to dye cotton and wool with excellent fastness. However, as is the case with many other mordant dyes, it gave way to the vat or the azoic dyes, which are applied by much simpler dyeing procedures. 

Synthetic alizarin (5.1), Cl Mordant Red 5 (5.2) and Cl Mordant Orange 1 (5.3), the first azo dye capable of forming a metal complex, in this case via the salicylic acid residue, are examples of the simple mordant dyes in widespread use at the time when Werner propounded his theory. The first metal-complex dyes to be prepared in substance, rather than within the fibre, were discovered by Bohn of BASF in 1912 by treating hydroxyanthraquinonesulphonic acids with a warm solution of a chromium(III) salt. In the... 

A simple spot test was used for the identification of procaine, and other drugs [30], The method uses one or more of the following reagents 0.4% Alizarin red S (C.I. Mordant Red 3) in 20% acetic acid, 0.3% indigo carmine (C.I. Acid Blue 74), 0.4% indigo carmine in 30% acetic acid,... 

Materials. The wool fabric was a plain-weave worsted wool, style 6561, from Burlington Industries. The silk fabric was a degummed silk crepe, style 601, from Testfabrics, Inc. The dyes were >95% pure and were from the following sources alizarin (C. I. Mordant Red 8) from Aldrich Chemical Co. brazilin (C. I. Natural Red 24) from J. T. Baker Chemical Co. and carminic acid (C. I. Natural Red 4) from H. Kohnstamm Co., Inc. The five reagent grade metal salts used were aluminum potassium sulfate, stannous chloride, cupric sulfate, ferrous sulfate, and potassium dichromate from J. T. Baker Chemical Co. 

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