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Chicago acid

Chicago acid (l,8-dihydroxy-naphthalene-2,4- disulfomc acid) [82-47-3... [Pg.192]

Direct Blue 218 had reported sales of 623 t valued at 4.4 million ia 1987. It is produced from Direct Blue 15 (76) by metallizing and elimination of methyl groups from the methoxide to form the copper complex. Direct Blue 15 (76) is prepared by coupling o-dianisidine [119-90-4] to two moles of H-acid (4-amiQO-5-hydroxy-2,7-naphthalenedisulfonic acid) under alkaline pH conditions. Other important direct blues iaclude Direct Blue 80 (74), (9-dianisidine coupled to two moles of R-acid (3-hydroxy-2,7-naphthalenedisulfonic acid [148-75-4]) followed by metallizing to form a bis copper complex, and Direct Blue 22 (77), an asymmetrical disazo dye, prepared by coupling o-dianisidine to Chicago acid [82-47-3] and 2-naphthol. Direct Blue 75 (78) is an example of a trisazo dye represented as metanilic acid — 1,6-Q.eve s acid — 1,6-Q.eve s acid — (alb) Ai-phenyl J-acid. [Pg.443]

Technical Observations. Tetrazotized benzidinedicarboxylic acid gives, with 2 moles of l,8-aminonaphthol-2,4-disulfonic acid (Chicago acid, see page 217), a disazo dye which, in tlie form of its copper compound on viscose silk, gives a bright blue shade having extraordinary light fastness. [Pg.350]

Amino-8-naphtliol-2,4-disulfonic acid (Chicago acid or S.S. acid)... [Pg.376]

COXnPLING OF o-TOLIDINE AND CHICAGO ACID (Prepaiatioa of a Salt-free Azo Dye)... [Pg.7]

The test for completeness of coupling involves testing for excess diazonium salt (o) and for excess Chicago acid (b) ... [Pg.63]

Throughout the coupling an alkaline reaction should be maintained and sodium carbonate added if the alkalinity falls. If the mixture gives tests for both diazonium compoimd and Chicago acid, insufficient time has elapsed for complete coupling. A little more Chicago add should be added (in alkaline solution) if a deficiency is shown. [Pg.63]

The red impiuity is another dye produced by coupling of the diazonium salt with an oxidation-product which is present in the technical Chicago acid. It is easier to free the blue dye of this red impurity by resalting than to purify the Chicago acid. However, in the case of Trypan blue (tolidine coupled with two moles of H acid) the red mpurity cannot be removed by salting. [Pg.63]

In a 3-I. beaker a paste is made from 82 g. (0.21 mole) of 88 per cent technical Chicago acid (i-amino-8-naphthol-2,4-disul-fonic acid) (Note 3) and 500 cc. of water, and solution effected by the addition of 8 g. (0.2 mole) of sodium hydroxide in 30 cc. of water, testing with litmus toward the end and leaving the reaction stiU acid (Note 4). The solution is cooled to 18° by the addition of ice, and just before the coupling 35 g. (0.33 mole) of anhydrous sodium carbonate is added. [Pg.13]

With dgorous mechanical agitation the diazonium salt solution is run into the Chicago acid solution rather rapidly. The blue dye which separates at first, gradually dissolves on fmther stirring. After one-half horn the solution is tested for alkalinity (Note s) nd for completeness of coupling (Notes 6 and 7). [Pg.13]

Broenner acid Casella s acid Chicago acid (SS acid) chromotropic acid Cleve s acid crocein (Bayer s acid) epsilon acid G acid... [Pg.115]

Chicago acid. (l-amino-8-naphthol-2,4-disul-fonic acid 8-amino-l-naphthol-5,7-disulfonic acid SS acid 1,8,2,4-acid 2-sulfur acid). [Pg.270]


See other pages where Chicago acid is mentioned: [Pg.192]    [Pg.495]    [Pg.502]    [Pg.291]    [Pg.96]    [Pg.93]    [Pg.192]    [Pg.1051]    [Pg.47]    [Pg.26]    [Pg.557]    [Pg.125]    [Pg.378]    [Pg.49]    [Pg.49]    [Pg.62]    [Pg.63]    [Pg.64]    [Pg.13]    [Pg.15]    [Pg.15]    [Pg.17]    [Pg.120]    [Pg.16]    [Pg.270]    [Pg.960]    [Pg.1102]    [Pg.1171]    [Pg.1194]    [Pg.125]   
See also in sourсe #XX -- [ Pg.13 , Pg.16 ]

See also in sourсe #XX -- [ Pg.13 ]

See also in sourсe #XX -- [ Pg.13 , Pg.16 ]

See also in sourсe #XX -- [ Pg.13 ]

See also in sourсe #XX -- [ Pg.13 , Pg.16 ]

See also in sourсe #XX -- [ Pg.897 ]




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Chicago

Tolidine and Chicago Acid

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