Direct Orange

Stilbene dyes of importance aie mosdy direct yellow dyes for ceUulosic fibers, especially paper. There have been several red and blue stilbene-containing dyes reported, but they have not (ca 1996) been developed to commercial importance. There are brown leather dyes which are stilbene-based. The most important stilbene dyes are those known siace the 1880s. The commercial importance of Direct Yellow 11 (1883), Direct Orange 15 (1888), Direct Yellow 4 (1886), and Direct Yellow 106 (1936) attest to the value, properties, and durabiUty of stilbene yellow dyes. 

Condensation products of 4-nittotoluene-2-sulfonic acid or its detivatives together with aromatic amines. Direct Orange 28 (Cl 40065) (4) is an example. The amine in this case is i)i n -diaminoben2ene. 

Azo-stilbene dyes formed by condensation of 4,4 -dinitro-2,2 -stilbenedisulfonic acid or 4,4 -dinitro-2,2 -dibenzyldisulfonic acid (1) with aminoazo compounds. Direct Orange 34 (Cl 40215) [32651-66-4] (5) is a representative ... 

Direct Orange 15 (Cl 40003) [1325-35-5] (13), which is made by reducing the alkaline condensation product equivalent to Direct YeUow 11 with sulfide or formaldehyde, is an important paper dye used in dyeing brown paper for bags. 

The a2oxy and nitro groups in Direct YeUow 11 are reduced to a2o and amino groups in Direct Orange 15. Direct YeUow 6 (Cl 40006) (14) is a greener and brighter shade of yeUow than Direct YeUow 11 and is made by reductive a2o formation from 4,4 -dinitro-2,2 -stilbenedisulfonic acid to an a2o and a2oxy dye. 

Direct Yellow 4, Direct Yellow 11, Direct Yellow 106, and Direct Orange 15 are the most important stilbene dyes, accounting for most sales of this type. Estimated volumes and values for Hquid and powder forms appear in Table 3 (38). 

Direct Oranges. AU principal commercially produced direct oranges are of disazo or stUbene chemical composition (Table 5). Direct Orange 102 (65) (R = COO Na+ ), is manufactured by first coupling aniline to 6,6 -ureylenebis-l-naphthol-3-sulfonic acid foUowed by a second coupling with /)-aminobenzoic acid [150-13-0]. 6,6 -Ureylenebis-l-naphthol-3-sulfonic acid [134-47-4] is the coupling component in many of the most important direct colors. It is produced by phosgenation of two moles of J-acid (6-ainino-l-naphthol-3-sulfonic acid). 

Other commercially important direct oranges iaclude Direct Orange 26 (66) (R = H) (2 mol aniline coupled to 6,6 -ureylenebis-l-naphthol-3-sulfonic acid), and Direct Orange 72 (67) which is obtained by phosgenatiag two moles of 7-amiQO-l,3-naphthalenedisulfonic acid coupled to cresidine [120-71 -8]. 

Fig. 4. Carbocychc azo dyes. Disperse Yellow 3 [2832-40-8] (Cl 11855) (26) is used to dye polyester Reactive Orange 1 [6522-74-3] (Cl 17907) (27) is a cotton dye Direct Orange 26 [25188-23-2] (Cl 29150) (28) is a dye for paper Synacril Fast Red 2G [48222-26-0] (Cl 11085) (29) dyes acrylic fibers Acid...

Miscellaneous Dyes. Other classes of dyes that stiU have some importance are the stilbene dyes and the forma2an dyes. Stilbene ( es are in most cases mixtures of dyes of indeterminate constitution that are formed from the condensation of sulfonated nitroaromatic compounds ia aqueous caustic alkah either alone or with other aromatic compounds, typically arylarnines (5). The sulfonated nitrostilbene [128-42-7] (79) is the most important nitroaromatic, and the aminoa2oben2enes are the most important arylarnines. Cl Direct Orange 34 [2222-37-6] (Cl 40215-40220), the condensation product(s) of (79) and the aminoa2oben2ene [104-23-4] (80), is a typical stilbene dye. 

Strain L-25 (newly MnP Direct-Orange 26, Direct Red 31, Direct [25]... 

Direct Yellow 12 Direct Green 6 Direct Brown 2 Direct Black 38 Direct Blue 15 Direct Red 23 Congo Red Direct Orange 26 Tartrazine P. chrysosporium ZrOCl2-activated pumice [54]... 

Direct orange dyes, 9 402-403 Directories, standards and specifications, 15 769... 

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