C.I. acid yellow

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 ... 

Many yellow dyes were of the azopyrazolone type, but these have now been largely superseded by azopyridone dyes. Azopyridone yellow dyes are brighter, stronger and generally have better fastness properties than azopyrazolone dyes. Both azopyrazolone and azopyridone dyes exist in the hydrazone tautomeric form. Typical dyes are the azopyrazolone C.I. Acid Yellow 23 (88) and the azopyridone (89). 

These dyes are now of only minor commercial importance, but are of interest for their small molecular structures. The early nitro dyes were acid dyes used for dyeing natural animal fibers such as wool and silk. They are nitro derivatives of phenols, e.g., picric acid (4) or naphthols, e.g., C.I. Acid Yellow 1, 10316 [846-70-8] (5). 

Phenyl-5-Pyrazolones as Coupling Components. Especially lightfast yellow shades are obtained by using l-phenyl-5-pyrazolone coupling components. The first representative of the class to appear was Tartrazine, C.I. Acid Yellow 23, 19140 [1934-21-0], which is prepared today from l-(phenyl-4 -sulfonic acid)-3-car-boxy-5-pyrazolone as the starting compound, obtained from oxaloacetic ester and phenylhydrazine-4-sulfonic acid and coupling with diazotized sulfanilic acid. 

C.I. Acid Yellow 76, 18850 [6359-88-2] (14), is obtained by coupling diazotized 4-aminophenol onto the pyrazolone component and then esterifying with -toluene-sulfonic acid chloride in an alkaline medium. The toluenesulfonic ester group substantially improves the fastness to milling and makes the shade obtained largely independent of pH the lightfastness is not quite as good as that of C.I. Acid Yellow 17. 

An important discovery was the realization that diaminodiphenyls substituted in the 2,2 -positions are outstandingly suitable for the manufacture of very wash-fast and millingfast wool dyes, while the substantivity toward cellulosic fibers is reduced. A number of important acid wool dyes have been developed on this basis, for example, C.I. Acid Yellow 44, 23900 [2429-76-7] (15). 

In the manufacture of this dye bis-diazotized 5,5 -dimethylbenzidine-2,2 -di-sulfonic acid is coupled to two equivalents of /V - a c et o ac et y 1 a n i 1 i n c. The clear, intense, greenish yellow dyeing obtained on wool is millingfast and exhibits excellent wetfastness but only moderate lightfastness. C.I. Acid Yellow 42 is a further member of this series (see Section 3.9.3). 

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). 

Group B dyes are used almost exclusively for clothing textiles, for which more stringent requirements are placed on wetfastness. Some of the typical azo dyes of this type are C.I. Acid Yellow 65, 14170 [6408-90-8] (34) and C.I. Acid Blue 113, 26360 [3351-05-1] (35). 

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. 

In contrast, 1 2 complexes contain one metal ion and two dye ligands and tend more towards dyeing the surface. This system is characterized by five- or six-membered rings, with the metal in the center of the octahedral structure. Metals are the trivalent, six-coordinated chromium, cobalt, and iron ions. Today, the principles underlying the structure and syntheses of metal-complex dyes are well known. Examples are C.I. Acid Blue 193, 15707 (1 2 Chrome) [12392-64-2] (11) and C.I. Acid Yellow 151, 13906 (1 2 Chrome) [12715-61-6] (12). 

Currently used water soluble yellow ink-jet dyes include monoazo dyes C.I. Acid Yellow 17, 18965 [6359-98-4] and C.I. Acid Yellow 23, 19140, [1934-21-0] which exhibit symmetrical narrow absorption bands, as well as the disazo dyes C.I. Direct Yellow86, 29325 [50925-42-3] and C.I. Direct Yellow 132 [61968-26-1]. Recently developed, improved yellow dyes include disazo dye 5 of the type C.I. Direct Yellow 86, 29325, but modified by introducing carboxyl groups. Similar to C.I. Direct Black 195, this dye shows a high waterfastness on uncoated paper due to differential, pH-dependant solubility [3,12],... 

As the name suggests, this very small class of organic dyes has at least one nitro group as the chromophore. Nitro dyes invariably are yellow or orange and are important for their economical cost and good lightfastness. Examples include the dyes shown in Fig. 13.78-C.I. Acid Orange 3 (A), C.I. Disperse Yellow 42 (B), C.I. Acid Yellow 1 (C), and... 

Type E1 D-+E1 Synthesis. Dyes of this type require the conversion of an aryldiamine to a tetrazonium compound (one that has two diazonium groups), in a process know as tetra-zotization. See Fig. 13.93, which involves environmentally friendly alternatives to benzidine. Following tetrazotization, one tetrazonium molecule reacts with two coupler molecules to produce the target dye, examples of which are provided in Fig. 13.94 (11 C.I. Direct Red 28 (Congo Red), 12 C.I. Direct Yellow 12, and 13 C.I. Acid Yellow 42). Disazo dyes prepared this way include dye 14 (C.I. Direct Blue 15), which is converted to the important bis-copper complex, C.I. Direct Blue 218 (see Fig. 13.95). 

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. 

SYNS AIZEN URANINE CALCOCID URANINE B4315 9-o-CARBOXYPHEN iX-6-HYDROXY-3-ISOX.ANTHONE, DISODIUM SALT CERTIQUAL FLUORESCEINE C.I. 766 C.I. ACID YELLOW 73 C.I. 45350 DISODIUM S.M.T D C YELLOW No. 8 DISODIUM-6-HY DROXY-3-OXO-9-XANTHENE-o-BENZOATE FLUORESCEIN SODIUM B.P FLUORESCEIN, soluble FLUOR-I-STRIP A.T. FUL-GLO FUNDUSCEIN FURANIUM HIDACID UIL XINE NCI-C54706 RESORCINOL PHTHALEIN... 

SYNS ACIDIC METANIL YELLOW ACID LEATHER YELLOW PRW ACID LEATHER YELLOW R ACID METANIL YELLOW ACID YELLOW 36 AIZEN METANIL YELLOW AMACID YELLOW M BRASILAN METANIL YELLOW BUCACID METANIL YELLOW CALCOCID YELLOW MXXX C.I. 13065 C.I. ACID YELLOW 36 C.I. ACID YELLOW 36 MONOSODIUM SALT DIACID METANIL YELLOW ENIACID METANIL YELLOW GN EXT D C YELLOW No. 1 FENAZO YELLOW M HIDACID METANIL YELLOW HISPACID YELLOW MG JAVA METANIL YELLOW G KITON ORANGE MNO KITON YELLOW MS METANILE YELLOW O METANIL YELLOW 1955 METANIL YELLOW C METANIL YELLOW E METANIL YELLOW EXTRA METANIL YELLOW F METANIL YET. LOW G METANIL YELLOW GRIESBACH METANIL YELLOW K METANIL YELLOW KRSU METANIL YELLOW M3X METANIL YELLOW O METANIL YELLOW PL METANIL YELLOW S METANIL YELLOW SUPRA P METANIL YELLOW VS xMETANTL YELLOW W S METANIL YELLOW Y METANIL YELLOW YK MITSUI METANIL YELLOW MONOAZO REMADERM YELLOW HPR SHIKISO METANIL YELLOW SYMULON METANIL YELLOW ... 

Supramine Yellow GW/C.I. Acid Yellow 61, replaceable by Telon Yellow GW micro (DyStar)... 

Nitro dyes are nitrated aromatic compounds which dye protein fibres and are classified as acid dyes. Naphthol Yellow (C.I. acid yellow 1), formula (6), is an example ... 

C.I. ACID YELLOW 13 C.I. ACID YELLOW 41 C.I. ACID YELLOW 27 C.I. ACID YELLOW 17... 

The most significant assistant in the application of these dyes is the acid added to the dyebath. Many acid dyes will not exhaust on wool at all unless the dyebath has been acidified. If, for example, wool is boiled gently for half an hour with 5 per cent of Acid Magenta, it is only faintlystained. When 4 to 5 per cent of sulphuric acid is also added, however, the wool is dyed a heavy shade, and exhaustion is virtually complete. Some experiments reported by Lister (J.S.D.C., 1949, 98) show the relationship between acid and exhaustion of Azo Rhodine 2G (C.I. acid red 1) and Xylene Fast Yellow P (C.I. ACID YELLOW 61) on purified wool. 

Particularly bright pinks require Lissamine Rhodamine G (C.I. acid red 50) or Lissamine Rhodamine B (C.I. acid red 52), and for extremely vivid yellows Lissamine Flavine FF (C.I. acid yellow 7) is used. Most of the dyes in this group can be used in combination with each other in shades where mixtures are necessary for matching. With the fast acid dyes it is not so easy to match shades with mixtures. Their tendency is towards uneven adsorption, and if the distribution of two or more components is not uniform, the differences in tone of the colour are much more apparent than equivalent differences in depth. The best results are, therefore, obtained by selecting a self-colour which matches the pattern or, if this is impossible, one which is so close that only a very small proportion of another dye is necessary. 

Synonyms C.I. acid yellow d c yellow no. 10 acid yellow 3 food yellow 13... 

Synonyms acid yellow 36 C.I. 13065 3-[[4-(phenylamino)phenyl]azo]-benzenesulfonic acid monosodium salt C.I. acid yellow 36 m-[(p-anilinophenyl)azo]benzenesulfonic acid sodium salt sodium salt of metanilyazodiphenylamine tropaeolin G extract D and C Yellow Number 1 Uses dye used in leather as indicator (pH) in laboratories A... 

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