• Title/Summary/Keyword: azo dyes

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Photochromism of Cationic Azo Dyes Containing 2,4-Dimethylimidazole (2,4-디메틸이미다졸환을 가지는 아조계 카디온염료의 포토크로미즘)

  • Cho, Myung Lae;Yoon, Nam Sik;Lim, Yong Jin
    • Textile Coloration and Finishing
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    • v.3 no.3
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    • pp.1-5
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    • 1991
  • Cationic azo dyes were synthesized by coupling aniline and its derivatives with 2,4-dimethyl imidazole as a coupler, and their photochromic behavior was investigated. The dyes exhibited little photochromism on wool, but to a considerable degree on Dacron T92(anionic modified polyester), the photochromism being prominent for the dye with electron-releasing substituent on diazo component. Little photochromism on wool can be attributed to a decreased mobility of dye by the various interactions between the dye and wool molecules, which interferes the cis-trans isomeriation of dye. On Dacron T92 there can not be any obstacle for the cis-trans isomerization of dye, hence reversible color change may occur. The electron-releasing substituent on diazo component may be helpful for the photochromism of dye by increasing the n-electron density of phenyl ring, which can stabilize the cis-form of the dye by the interaction with the positive charge of imidazole ring.

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Spectrophotometric Determination of Antihistamines by Using Metal Indicators NN, EBT and Calcon as Color Developing Agents. (항 히스타민제의 흡광광도정량법)

  • 옥지원
    • YAKHAK HOEJI
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    • v.18 no.2
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    • pp.133-144
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    • 1974
  • The metal indicator, acidic azo dyes NN, EBT and Calcon are utilized to analyse quantitatively chlorpheniramine, tripelenamine and diphenhydramine forming insoluble ion pair in aqueous solution at proper pH values between the acidic azo dyes and the sample molecules, these compexes are extracted by organic polar solvents, and organic layer is determined spectrophotometrically. Generally, the absorption maxima of the complexes are shifted to longer wavelengths compare to the absorption maxima of the dyes themselves. The binding ratio of the ion pair forming complex molecules in chloroform soln, are as follows ; NN-antihistamines (chlorpheniramine, tripelennamine, diphenhydramine) are NN-1 to antihisamine-1, EBT-antihistamines are EBT-2 to antithistamines a and Calcon-antihistamines are Calcon-3 to antithistamines-1. These coomplexes in chloroform soln. are very stable, and show higher absorbance than the other organic polar solvents. The binding state of complexes were presumed intermolecular hydrogen bond by their infrared spectra. In the mixture solution of three samples, the aqueous phase is buffered at pH 1.0, and benzene is used to extract ion pair of diphenhydramine EBT complex selectively. At pH 1.0 of aqueous layer, Calon-diphenhydramine complex is also extracted selectively by benzene. However, in this case very small amount of chlorpheniramine-calcon calcon simultaneously. The binding state of diphenhydramine-EBT and diphenhydramine-calcon in benzene are smae as the complexes in chloroform. But the absorption maxima of the complexes in benzene are shifted to shorter wavelenlgths than the complexes in chloroform.

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Influence of Food Dye on the Activity of Hepatic Azo Reductase and the Effect of Flavin (식용 Azo 색소가 Hepatic Azo Reductase에 미치는 영향과 Flavin의 효과)

  • 윤혜정;원형란
    • Journal of Food Hygiene and Safety
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    • v.2 no.1
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    • pp.9-14
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    • 1987
  • With the market of food products, the use of food additives is on the increase. The dye as food additives, can be used for some foods which are difficult to preserve their own colors. It can be also classified as tar dye, vegetable dye and mineral dye. Because tar dye has dense toxicity, only 15 articles among them are legally allowed to be used. Among the allowed articles, the azo compound amaranth, tartrazine, sunset yellow, and allura red, were used in determining and comparing rat hepatic azo reductase activity and we observed the flavin's effects as follows: 1. Investigation with amaranth as substrate gave an apparent Km of $645\;\mu\textrm{M}$ and Vmax of 50 n mol/min/mg protein. 2. On investigation using a fixed amaranth concentration over a range of flavin concentration, FAD significantly increased the activity of the azo reductase compared with only minor increases in reaction mediated by the NADPH-generating system alone. 3. On investigation with amaranth, tartrazine, sunset yellow allura red as electron acceptor in the absence or presence of 300 mM-FAD, sunset yellow was reduced at a rat similar to amaranth, tartrazine was reduced at a slower rate and allura red was reduced a little more rapidly.

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Synthesis of Super Hydrophobic Orange Dyes Having Maximum Absorption at 450-500nm for Pure Polyolefin Fibers (450-500nm의 최대흡수를 가지는 순수 폴리올레핀 소재용 초소수성 오렌지 염료의 합성)

  • Kim, Taekyeong;Ryu, Myeonghwa
    • Textile Coloration and Finishing
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    • v.26 no.3
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    • pp.165-172
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    • 2014
  • Novel super hydrophobic orange dyes having maximum absorption band at 450-500nm were synthesized to dye polyolefin fibers such as polypropylene and ultra high molecular weight polyethylene fibers, using 4-alkylanilines and ${\beta}$-naphthol. Their absorption spectra at visible range showed almost the same, which meant that the alkyl substituents introduced to chromophore did not affect on color appearance of the dyes. Considering both color strength and wash fastness, the decyl-substituted dye was determined as the optimum one practically. From the dyeing results at various conditions, the optimum dyeing was $130^{\circ}C$ for 1 hour with 5% owf of dyes. The good fastness ratings to washing, rubbing were obtained showing 4-5 for both fibers. Light fastness was also acceptable giving rating 3-4 for polypropylene fibers and rating 3 for ultra high molecular weight polyethylene fibers.

Synthesis and Dyeing Properties of novel azo dyes with ester functional group derived from phthalimide (Diester계 치환기를 가지는 phthalimide계 azo 염료의 합성 및 염색특성)

  • Lee, Hyeon-Yeong;Choe, Jong-Yun;Gwon, O-Tak;Choe, Jae-Hong
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2008.10a
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    • pp.23-24
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    • 2008
  • 본 연구는 고 세탁견뢰도 특성을 가진 Phthalimed계 염료를 합성하고, 일반 PET 섬유 및 해도형 PET에 염색하여 염색거동과 견뢰도 특성에 대해 알아보았다. 대부분의 염료는 5급 이상의 세탁견뢰도를 가지며, 몇가지 염료는 70%이상의 염착률을 가진다.

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