Eriochrome Azurol

Chloro-2-aminophenol is used chiefly for the preparation of blue azo dyes which can be after-chromed. Its combinations with chromotropic acid and with acetyl-H acid were the purest chrome blues known before the discovery of the chroming triphenylmethane dyes (eriochrome azurol). The latter dyes are superior in depth and brilliance of color, but are not as fast to light as the azo dyes from 4-chloro.2-aminophenol and chromotropic acid or acetyl-H acid. 

Salicylic and cresotinic acids are used in the preparation of azo dyes and of tri-phenylmethane dyes of the aurine type (eriochrome azurol B). These acids confer upon the dyes the property of going onto metal mordants, particularly chromium mordants, and also of forming complex compounds, in substance, with suitable metal salts. Salicylic acid is also widely used in the pharmaceutical industry. 

Eastman Fast Blue GFI 514 Eclipse Brilliant Blue 2RL, 467 Eriochrome Azurole B, 436... 

A considerable increase in the sensitivity of methods for palladium determination has been found with triphenylmethane reagents in ternary systems that include cationic surfactants, e.g., Eriochrome Cyanine R with CP [79], Chromal Blue G with CTA (e = 1.0-10 ) [80], Chrome Azurol S-CTA (or -CP) [81], Eriochrome Azurol B-CTA (e = 1.15-10 ) [82], and Eriochrome Azurol G-CTA [83]. 

Triphenylmethane reagents have gained considerable importance in the determination of uranium [110]. In this group it is worth mentioning Chrome Azurol S, especially if used in the presence of cationic surfactants (CP, CTA, Septonex, etc.) (pH 4-5, e = 1.010 -1.2-10 at -630 nm) [111-115]. Other reagents suggested include Eriochrome Cyanine R (with CP) [116], Eriochrome Azurol B (pH 4-7 with CTA or CP, e = 1.3510 ) [114], and Chromal Blue G (with CTA) [117]. 

Eriochrome cyanine (R), chrome azurol (S), and eriochrome azurol (B) Eight mixtures of a reactive dye (4 1) (monochloro-1,3, 5-triazene) and a direct dye... 

Strictly, the name Eriochrome azurol G applies to the disodium salt. 

Carboxy-5-methyl-4-oxo-2,5-cyclohexadien-l-ylidene) (2,6-dichloropheny[)methy[ -2 hydroxy-3-methylbenzoic acid, 9CI. Pontachrome azure blue B. Chrome fast pure blue B. C.I. 43830. C.I. Mordant blue I. Eriochrome azurol B. Acid chrome pure blue [15012-28-9]... 

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