Dianisidine-blue

The nitrous acid liberated at the anode reacts with the amine to form a diazonium compound, and this immediately condenses with the phenolic substance which is present to produce the azo-dye. Cooling is desirable though not so important as in the ordinary chemical method, since the diazonium compound couples with the phenol immediately it is formed but a diaphragm must be used to separate anode from cathode. Orange II, Congo red, dianisidine blue, and many other colours have been formed in this way. 

Results Orange II Congo Dianisidine- blue Chrvsamine " G Rocceline... 

Helidon Pink R Indanthrene Blue RS Fast Red G base Dianisidine Blue Indigo... 

Diamond Black 11 Dianisidine Blue, 445 Diazamine Blue Q 423 Diazamine Fast Green GL, 423 Diazo Brilliant Orange GR, 415 — Brown 3RNA.CF, 405 -Hi Fast Yellow 3GLL, 423 Diazophenyl Red FN, 423 Diphenyl Blue 5B, 414... 

Phloroglucinol is Hsted in the Colourindex as Cl Developer 19. It is particularly valuable in the dyeing of acetate fiber but also has been used as a coupler for azoic colors in viscose, Odon, cotton (qv), rayon, or nylon fibers, or in union fabrics containing these fibers (157). For example, cellulose acetate fabric is treated with an aromatic amine such as (9-dianisidine or a disperse dye such as A-hydroxyphenylazo-2-naphthylamine and the amine diazotizes on the fiber the fabric is then rinsed, freed of excess nitrite, and the azo color is developed in a phloroglucinol bath at pH 5—7. Depending on the diazo precursor used, intense blue to jet-black shades can be obtained with excellent light-, bleach-, and mbfastness. 

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. 

Many of the premetallised direct dyes are symmetrical structures in the form of bis-1 1 complexes with two copper(II) ions per disazo dye molecule. Scheme 5.12 illustrates conversion of the important unmetallised royal blue Cl Direct Blue 15 (5.43), derived from tetrazotised dianisidine coupled with two moles of H acid, to its much greener copper-complex Blue 218 (5.44) with demethylation of the methoxy groups as described above. Important symmetrical red disazo structures of high light fastness, such as Cl Direct Red 83 (5.45), contain two J acid residues linked via their imino groups. Unsymmetrical disazo blues derived from dianisidine often contain a J acid residue as one ligand and a different coupler as the other, such as Oxy Koch acid in Cl Direct Blue 77 (5.46), for example. 

F. Blue 2B 250% (C.I. Direct Blue 6, C.I. No. 22610), Direct Brown BRL 200% (C.I. Direct Brown 95, C.I. No. 30145) Fabricolor Inc. Evans Blue (C.I. Direct Blue 53, C.I. No. 23860), Benzo Azurine G (C.I. Direct Blue 8, C.I. No. 24140) Pfaltz and Bauer Inc. Benzidine was obtained from Sigma Chemical Co., o-tolidine from Fisher Scientific Corp. and 3,3 -dimethoxybenzidine (o-dianisidine) from Eastman Kodak Company. Aniline, -aminophenol, -phenylenediamine and -nitroaniline used in the interference study were obtained from Chem Service Inc. 

This system resolved the aniline peak (retention time (rt) = 2.67 min) from the benzidine peak (rt = 2.27 min) as can be seen in Figure 2. Other potential interferences were selected for study by looking at the expected fragments from the reduction of various dyes. Reduced dye samples were spiked with aniline (rt = 2.67 min), -aminophenol (rt = 1.97 min), -phenylenediamine (rt = 1.93 min) and -nitroaniline (rt = 3 16 min). None of these materials interfered with the detection of the benzidine peak. To determine if other types of dyes might interfere with the analysis, two sets of filters were spiked at low and high levels separately with C.I. Direct Red 28 (13 7 yg and 137 yg), C.I. Direct Blue 53 formulation (o-tolidine-based) (21.2 yg and 212 yg) and C.I. Direct Blue 8 formulation (o-dianisidine-based)(23.3 yg and 233 yg). 

Figure 3. Chromatogram of a 10- injection of reduction products of a mixture of C.l. Direct Red 28 (28.8 fig), C.l. Direct Blue 53 (28.6 fig) and C.l. Direct Blue 8 (34.4 fig) showing resolution of benzidine (retention time = 2.33 min), o-dianisidine (retention time = 4.02 min), and o-tolidine (retention time = 4.27 min). Chromatographic conditions as in Figure 2.

As a rule many of these dyes only have moderate lightfastness on paper. To improve this metal complexes are used, particularly with the blue azo dyes. Because planarity of the dye molecule is advantageous for a good dyeing, virtually only Cu2+ complexes such as C.I. DirectBlue 218,24401 28407-37-6] (18) are of interest for paper. 3.3 -Dimcthoxy-4,4 -biphcnyldiaminc (o-dianisidine) has proved particularly suitable, because after coupling with a 1-naphthol derivative demethylative copperization can take place. 

By linking heterocyclic ring systems such as triphenbisoxazine with 1,3,5-tri-chlorotriazine brilliant blue and lightfast dyes 20 were developed which are completely metal-free, contain no dianisidine, and have high substantivity on paper. [9]. 

Benzidine derivatives like 3,3 -dimethylbenzidine and 3,3 -dimethoxybenzidine (o-dianisidine) (Figure 27), are used as dyes or intermediates for dyestuffs or pigments (e.g.. Trypan Blue, Acid Red 14, and Direct... 

At the same time /9-hydroxynaphthoic acid was being used, to some extent, in the textile industry for printing because, when coupled with diazotized dianisidine, (4), below, it gave a blue not dissimilar to indigo. 

The rate at which dyes disappear from the blood may depend on the dissociation constants of dye-plasma protein and dye-cellular protein complexes. The excretion route also may be influenced by the affinity of a dye for plasma proteins. In a study (G20) of four related diazo dyes— Evans blue (ditoluidine), trypan blue (ditoluidine), Niagara sky blue (dianisidine), and Niagara sky blue 6B (dianisidine)—dianisidine dyes disappeared at a faster rate from the circulation than ditoluidine dyes. The position of the four sulfonic acid groups in these dyes is also important shifting the groups from the 2,4 to the 3,6 positions increases the disappearance rate. These relative disappearance rates could be related to the protein binding of the dyes Evans blue, which disappears at a slow rate, is most firmly bound whereas Niagara sky blue, which disappears most quickly, is least firmly bound (R2). 

SYNONYMS Acetamine diazo black RD, azoene fast blue base, spectrolene blue B, setacyl diazo navy R, diacelliton fast grey G 3,3 -dimethoxybenzidine, o-dianisidine. 

Benzidine-based dyes such as Congo red, Amanil blue 2BX, Direct brown 95, Direct black 38, and o-tolidine- and o-dianisidine-based dyes in air may be analyzed by NIOSH Method 5013 (NIOSH 1984). The method involves passing 120-500 L of air through a... 

Blue 6B. See Direct blue 1 Blue anthraquinone pigment. See Indanthrone Blue base. See Dianisidine Bluebonnet extract Blue bottle extract. See Cornflower (Centaurea cyanus) extract Blue chamomile flower oil. See Chamomile (Matricaria chamomilla) flower oil Blue chamomile oil. See Matricaria (Chamomilla recutita) oil... 

Cl direct green 1 Cl direct green 1, disodium salt. See Direct green 1 Cl direct orange 6. See Direct orange 6 Cl direct red 2. See Direct red 2 Cl direct red 39. See Direct red 39 Cl direct violet 32 Cl direct violet 32 disodium salt. See Direct violet 32 Cl disperse black 6. See Dianisidine Cl disperse blue 7. See Disperse blue 7 Cl disperse blue 27. See Disperse blue 27 Cl dispersed red 71. See Disperse red 60 Cl disperse orange 11. See 1-Amino-2-methylanthraquinone... 

Dimethoxy-4,4 -biphenylene diisocyanate 3,3 -Dimethoxy-4,4 -biphenylene isocyanic acid ester. See Dianisidine diisocyanate 3,3 -((3,3 -Dimethoxy-4,4 -biphenylylene) bis (azo)) bis (5-amino-4-hydroxy-2,7-naphthalenedisulfonic acid), tetrasodium salt. See Direct blue 15 3,3 -Dimethoxy-4,4 -biphenylylene diisocyanate. See Dianisidine diisocyanate 1,2-Di-(3-methoxycarbonyl-2-thioureido) benzene. See Thiophanate-methyl... 

Farnesyl alcohol. See Farnesol Pascal 2004] Pascal 2005. See Stannous chloride anhydrous Pascal 4400. See Stannic chloride Fast acid magenta. See Acid red 33 Fast blue. See Dianisidine Fast blue 7GLN. See Direct blue 218 Fast brown RR salt. See 2,6-Dichloro-p-phenylenediamine... 

Acid black 52 Acid black 58 Acid black 60 Acid blue 15 Acid blue 25 Acid blue 104 Acid blue 113 Acid blue 118 Acid green 20 Acid orange 10 Acid red 13 Acid violet 12 Acid violet 49 Acid yellow 25 Acid yellow 42 Acid yellow 65 Basic blue 6 Basic orange 1 Basic orange 2 Basic red 2 Basic red 12 Basic yellow 2 4,4 -Diaminostilbene-2,2 -disulfonic acid Dianisidine Direct black 38 Direct blue 1 Direct blue 6 Direct brown 2 Direct brown 95 Direct green 1 Direct red 39 p-Rosaniline hydrochloride dye, liq. cryst. displays 1,4,5,8-Tetra-(phenylthio) anthraquinone dye, medicine Fluorescein dye, mfg. 

Acid violet 49 Acid yellow 3 Acid yellow 36 Basic blue 7 Basic orange 1 Basic orange 2 Basic red 1 Basic red 2 Basic red 12 Basic yellow 2 Basic yellow 37 Carbon black D C Orange No. 4 4,4 -Diaminostilbene-2,2 -disulfonic acid Dianisidine Direct black 38 Direct blue 6... 

Basic brown 4, dihydrochloride Basic orange 2 Dianisidine Direct blue 1 Direct yellow 11 Manganese sulfate (ous) Vat yellow 4 dye, textiles leather Acid orange 3 dye, thermoplastics Disperse yellow 54 dye, triacetate Disperse blue 72 dye, tunable lasers Basic red 1 dye, varnishes... 

Phenols can be detected with Fast Blue Salt B, diazo-tized orthanilic acid or dianisidine, alkaline chloramine T reagent, by spraying an ammoniacal silver nitrate solution, followed by exposure to UV light, or with a modified potassium ferricyanide-ferric chloride reagent, and also by exposing the wet layer successively to nitrogen dioxide (Cu + HNO3) and ammonia vapors. 

No hRf Substance UV2S4 Fast blue salt B-reagent Anisaldehyde-sulfuric acid-reag. o-Dianisidine-reg. ... 

---