Acid-fastness is usually defined by the Ziehl-Neelsen technique: staining in carbol-fuchsin, differentiation in HCl-alcohol, and counterstaining in methylene blue.8 As a result, acid-fast substances are red, non-acid-fast materials, blue. Some authors have felt that this property of differential staining resided in one specific type of compound, the mycolic acid type of long-chain fatty acid fo...

Bacilli from a number of tissues excised from cases of lepromatous and borderline leprosy, unlike mycobacteria, were found to lose their acid-fastness after treatment with pyridine.

A series of new monoazo disperse dyes containing pyrazolopyrimidine moieties was synthesized by coupling malononitrile or 3-aminocrotononitrile with 4-hydroxy- benzenediazonium chloride. Treatment of the resulting products with hydrazine hydrate yields the corresponding 4-arylazoaminopyrazoles, which then react with either 2,4-pentanedione and enaminonitriles or aryl-substituted enaminoketones ...

Three sulfatoethylsulfone reactive dyes have been synthesized and were applied to mill desized, bleached and mercerized cotton fabric. Effect of different dyeing parameters i.e. salt concentration, dyeing time, dyeing temperature and pH of dye solution were being optimized by exhaust dyeing method. The fixation (%F) of the synthesized dye molecules with the cotton fabrics was also studied. Cott...

In this investigation dyeing of alginate fiber was carried out after cationic treatment of 11 EPTAC (2, 3-Epoxypropyl Trimethyl Ammonium Chloride). Optimum dyeing process and 12 parameter show good dyeing performance when alginate fiber dyed with rhubarb dye. In addition 13 to cationic treatment is taken into account for alginate fiber to improve fastness, color strength, 14 breaking strength. ...

Silk yarns were dyed by using commercial basic, reactive and pre-metallised acid dyes. An aftertreatment with a commercial synthetic tanning agent (syntan) was applied to the dyeings and the aftertreated dyeings were further treated with metal salts in an attempt to improve wash fastness properties. When all samples (untreated, syntanned and syntanned/ backtanned speciments) were subjected five...

The aim of this study is the improvement of the photostability of anionic dye, methyl orange(MO), by intercalation into the hydrotalcite layer (Mg-F-MO LDH). It was found that the thermostability of MO was markedly improved by intercalation into the hydrotalcite host, whilst the photostability was enhanced slightly. The effect of the stability enhancement is larger when the amount of introduced...