Synthesis and mutagenic properties of direct dyes from …
T1 - Direct synthesis of intercalation compounds between a layered double hydroxide and an anionic dye
Synthesis and application of direct black dyes ..
III. Mordant and Chrome Dyes.These are coloured comIii. Mordant and Chrome Dyes.These are coloured com- pounds containing particular groups, usually OH or groups, capable of forming stable coloured lakes (co-ordinative com pounds) with metallic hydroxides, particularly with those of chromium, aluminium, iron and copper. The mordant dye-stuffs proper comprise many of the older natural colouring-matters, much as logwood, fustic, cutch, cochineal, Persian berries and brazilwood, but only a few synthetic dyes, which belong chiefly to the anthraquinone class (alizarine, purpurines, alizarine blue, ali zarine cyanines, anthragallol, etc.). Most of the mordant-dyeing colouring-matters of synthetic origin contain acid groups or or both) and may therefore be classified as acid-mordant colours. These are mainly used on a chromium mordant and are theref ore generally termed chrome colours. In wool dyeing the chromium mordant (sodium bichromate, chromium acetate or chromium fluoride) is applied to the wool either before or after dyeing, or even more frequently (metachrome or solochrome colours) both dye stuff and mordant (chromate) are added to gether to the dye-bath. The shades dyed with mordant and acid mordant dye-stuffs are generally much faster to alkalis and there fore to washing and milling than those obtained with ordinary acidic dyes, whilst the resistance to light, more particularly of those belonging to the anthraquinone group, is very good. Mor dant dyes are also employed in calico printing, in which case the solution of the dye-stuff suitably thickened is mixed with chromium acetate and acetic acid, printed upon the cotton cloth and steamed.
I. Basic Dyes.The basic dyes are salts. usually hydrochlorides of coloured bases containing amino or substituted amino-groups, such as etc. They dye animal materials wool, silk, leather, feathers, etc.directly from a neutral bath, but possess for vegetable fibres, jute excepted, only a small affinity. They are applied to cotton and linen by mordanting these fibres with tannin and a metallic salt, such as a salt of anti mony, which produce insoluble compounds with the dye base. In calico printing, for which dye-stuffs of the basic class find their chief application, a thickened mixture of the dye-stuff with acetic acid and tannin is printed upon the cotton. This is then steamed to drive off acetic acid, leaving the insoluble dye tannate, the fixation of which is completed by passing through a bath of anti mony potassium tartrate. The basic dyes can be applied to jute, hemp and cocoanut fibre without a mordant and are frequently used for dyeing these materials. Some are used for lake pigments for wall-paper printing, while the salts of certain dye bases with the higher fatty acids, oleic, linoleic, stearic or resin acids, are used for colouring oils, varnishes, etc.
as potential candidate for the synthesis of dyes and ..
All vat dyes are insoluble in water. To apply them to a fibre, for example cotton, they are placed in an alkaline solution (Table 4). The insoluble dye is reduced to form a colourless (leuco) anion which is soluble and possesses affinity for the fibre. This is then adsorbed by the fibre, sometimes in the presence of sodium chloride, conditions similar to that for direct dyes. After the dyeing process the original insoluble parent dye is regenerated within the fibre by oxidation, usually using a solution of hydrogen peroxide or simply air:
The acidic members of the anthraquinone class are represented by alizarine red WS, alizarine acid blues, acid alizarine green, alizarine saphirol, alizarine astrol, alizarine irisol, alizarine cyani nol, alizarine rubinol, alizarine direct blue, alizarine cyanine green, cyananthrols, etc. Many of these dye wool directly from an acid bath without a mordant while others give shades which are faster to washing when a mordant is used (acid-mordant dyes). The vat dye-stuffs of the anthraquinone series are the fastest dye stuffs known. They comprise the indanthrene (duranthrene) series, the caledon series, algol colours, cibanone colours, ponsol colours, etc., the first representative of which, indanthrene blue RS, was discovered in 1901 (vide supra). Many of these dyes have an extremely complex constitution, containing two or more anthraquinone residues united together by other groups or fused in such a way as to produce new ring structures. In these struc tures at least one of the two carbonyl (CO) groups of each anthra quinone residue remains intact, and it is to this group that the property of vat dyeing is to be attributed.
Key words: groups” for the synthesis of symmetrical direct dyes
N2 - Intercalation compounds between a layered double hydroxide and an anionic dye were directly synthesized by hydrolysis of mixed solutions of aluminium nitrate, magnesium nitrate, and the anionic dyes (indigo carmine or new coccine). The intercalated indigo carmine anions are possibly arranged with their molecular planes perpendicular to the hydroxide layers. The basal spacings of the new coccine intercalates suggested that the configuration of the new coccine anions in the interlayers changed upon washing. Intercalation of the dyes by anion exchange from layered double hydroxides with NO3- or Cl- as the interlayer anions was also conducted for comparison.
AB - Intercalation compounds between a layered double hydroxide and an anionic dye were directly synthesized by hydrolysis of mixed solutions of aluminium nitrate, magnesium nitrate, and the anionic dyes (indigo carmine or new coccine). The intercalated indigo carmine anions are possibly arranged with their molecular planes perpendicular to the hydroxide layers. The basal spacings of the new coccine intercalates suggested that the configuration of the new coccine anions in the interlayers changed upon washing. Intercalation of the dyes by anion exchange from layered double hydroxides with NO3- or Cl- as the interlayer anions was also conducted for comparison.
Liquid formulations of direct dyes - BASF …
The synthesis of Direct Yellow 11 is common knowledge.
Synthesis and mutagenic properties of direct dyes from 4,4′-diamino-p-terphenyl and 4,4′-diamino-p-quaterphenyl
The synthesis of some reactive dyes ..
Direct Dye: Direct Dye is a class of dyestuffs that are applied directly to the substrate in a neutral or alkaline bath
What is Dye,About Dyes,Definition of Dyes,Information …
The market in quantitative terms is made up of basic dyes, azo acid and direct dyes; disperse dyes ..
Direct Red 80 Dye content 25 % | Sigma-Aldrich
Basic dyes were amongst the earliest synthetic dyes. Indeed Mauveine is a basic dye. The chromophore is present as a cation and they are used nowadays in dyeing acrylic fibres (usually a co-polymer with propenonitrile (acrylonitrile) and a small amount of a co-monomer which contain sulfonate, -SO3-, and carboxylate, -CO2-, groups). These are ion-ion interactions (Tables 2 and 4).
Total Synthesis of Terpenoids Employing a …
Most of the direct dyes are azo compounds, often containing two or three azo groups. Examples include C.I. Direct Orange 25 which has -OH, -NHCO- and -N=N-groups all of which have the potential to form hydrogen bonds with the hydroxyl groups in cellulose:
Highly Convergent Total Synthesis of (+)-Lithospermic …
X. Tjiiazole Class.Characteristic grouping : The most important dye-stuff of this class is the diazotizable dye stuff, primuline, in which the typical thiazole group is present twice : This colouring-matter dyes cotton directly in primrose-yellow shades, which, owing to the presence of an amino-group, can be diazotized and coupled on the fibre. Thus the largely used primu line red is produced by passing cotton dyed with primuline through an acidified solution of sodium nitrite and afterwards through an alkaline bath of 13 -naphthol. The colours thus obtained are very fast to washing. Other members of the thiazole class which dye cotton directly, though they are not diazotizable, are chloro phenine yellow, Clayton yellow and thioflavine S. Thioflavine T has basic properties and is used in calico printing, giving very pure greenish-yellow shades. In the thiazole class also belong the direct-dyeing reds, erika, geranines, titan pink and diamine rose, which contain an azo-group in addition to the thiazole chromo phore. The thiazole chromophore is difficult to reduce and those dyes containing this group only are but little affected by reducing agents. When, however, as is the case with developed colours from primuline, an azo-group is also present, the latter suffers disruption and the parent thiazole remains.
Zinc Oxide—From Synthesis to Application: A Review - MDPI
Azo-dyes which do not contain a salt-forming group, acidic or basic, are insoluble in water and therefore cannot be used in ordinary dyeing operations. They are employed as pigment colours (ground with mineral materials), and for colouring oils, waxes and varnishes. Certain of them also find a large and increas ing application as colours produced on, or within, the fibre itself, and which on account of their insolubility are very resistant to washing, bleaching and light. The typical example of this class is para red, to which reference has already been made. This method of dyeing has been greatly extended by the introduction of the so-called azoic series, in which the cotton is impregnated with an anilide of j3 -oxynaphthoic acid (known commercially as a "naphthol AS" compound), such as and subsequently passed through a bath containing the diazo compound of a nitroaniline, nitrotoluidine, nitrochloroaniline, naphthylamine, etc. Certain of the reds obtained in this manner exhibit a very high degree of fastness, even resisting the process of cotton bleaching known as "bowking." The group of azo-dyes may be divided according to their dye ing properties into the following subdivisions: (a) Neutral or pigment colours; (b) basic dyes: a small group represented by chrysoidine, Bismark brown, and a few other products; (c) acidic dyes: a large group to which the ordinary wool yellows, oranges, scarlets and blacks belong; (d) mordant dyes or chrome dyes: used in dyeing fast colours on wool or in cotton printing; (e ) direct substantive or salt dyes: a large group of colouring-matters which have an affinity for cotton and other cellulose fibres; (f) acetate silk dyes (ionamines, S.R.A. colours, etc.) : a class of recent introduction, dyeing acetyl-cellulose ("Celanese," etc.), but having no affinity for cotton, linen, or viscose silk; (g) spirit soluble dyes : employed in the colouring of stains, varnishes, waxes and gasolene (petrol) .
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