Tinctorial properties

On the other hand, in spite of some interesting tinctorial properties, it does not seem that thiazolo dyes received wide application in the texlile industry because they suffer from lack of stability to light and chemical agents. 

There is a large number of heteroaromatic coupling components of very different structural types. l-Aryl-3-methyl-5-pyrazolones have been widely used for yellow and orange monoazo dyes since the end of the 19th century. Other types have become important as a source of new industrially produced dyes in the last two decades. In reviews on industrial aspects (e.g., Schwander, 1982) these coupling components are classified not on the basis of their structures, but from the viewpoint of what is important for tinctorial properties of the dyes obtained with these types of coupling components. Here we will use a structural approach to systematization. 

Cochineal, carminic acid, and carmines are approved as food colorants in the EU under code E 120, and their purity criteria are regulated.The amount of E 120 permitted in food ranges from 50 to 500 mg/kg. Carminic acid and carmine are considered very good food colorants due to their high stability and tinctorial properties. Solutions of carminic acid are yellow to orange, while carmines show various stable brilliant red hues. - ... 

The product is removed, washed with ether and recrvstallised from a little boiling water, shimmering needles with a metallic green reflex being obtained. The compound possesses the same stability and tinctorial properties as Methylene Blue.1 The course of the reaction may be represented thus ... 

From about 1930 onwards, developments in the field of naphthoquinone dyes concentrated on the use of naphthazarin and intermediates for the preparation of violet, blue, and green acid and disperse dyes [1]. More recently there has been interest in the synthesis and color and constitution properties of simple colored naphthoquinones, stimulated by the fact that such dyes have similar tinctorial properties to the anthraquinones but a smaller molecular size. The naphthoquinones provide a useful alternative to the anthraquinones for certain specialized applications, e g., as pleochroic dyes with improved solubility for liquid-crystal displays. As a result, research interest in these chromogens remains unabated, even though they have failed to make any major impact as textile dyes [2-8],... 

These pigments combine excellent tinctorial properties with outstanding durability, solvent fastness, lightfastness, heat fastness, and chemical resistance. Table 8.1 lists those shades currently available commercially. 

From this it may be conceived that the simultaneous presence of a basic auxochromic group and an acid-forming chromophor, or vice versa, gives rise to a weak dyestuff. The nitranilincs form a case in point they are weak dyestufis, while on the other hanu the nitrophenols have tinctorial properties much more fully eveloped. 

Diphenine of Gerhardt and Laurent [23] and hydrazoaniline of Haarhaus [24] are regarded as hydrazo-compounds they are probably diamidoazo-compounds, as they possess tinctorial properties in a marked degree, which is not usual in hydrazo-compounds. 

These dyes belong to the oxyazo series, and have within the last ten years attained enormous importance, on account of the beauty of their shades and their strong tinctorial properties. For these, and other reasons, they are worthy of being studied as a separate class. 

Diazo-compounds combine with phenols and amines to form azocompounds. The tinctorial properties of these bodies are generally weak, becoming intensified, however, by converting the carbonic acids into their ethers. 

The tinctorial properties of indigo are due to the presence of the chromophorous group ... 

The application of canarine depends on its property of dyeing cotton yellow from an alkaline solution. The shades vary from light yellow to orange-yellow, according to the concentration of the solution. They are very fast both to soap and light. In comparison with other artificial dyestuffs, canarine only possesses weak tinctorial properties. 

Haematoxylin is contained in logwood or campeachy, the wood of HcBmatoxylon campechianum. Although scarcely a dyestuff, haematoxylin is the only important constituent of logwood, as on oxidation it yields hasmatei n [2], a compound of strong tinctorial properties. 

In this work, as in the previous one, considerable weight has been laid upon the relationships existent between the constitution and tinctorial properties of the dyestuffs. 

A point of importance which is not to be underestimated is also the behaviour of cyclotrimethylenetrinitramine in a sanitary direction In contradistinction to most of the other nitro compounds it is absolutely non-polsonous, has no tinctorial properties, is completely odourless and tasteless and does not cause either in the form of dust or Bolutior. any irritant affeefions of the respiratory organs and the skin. In juries to the work people by the usual discolourations of the skin injurious action on the sense of taste, eruptions, headaches and easy chronic poisoning which are caused in the preparation and handling of the nitro compounds are therefore precluded and the complicated hygienic precautions hitherto necessary become... 

Initial studies with synthetic PrP peptides focused on the identification of protein domains that could be involved in the conformational conversion of PrP into disease-associated species. To test the hypothesis that this conversion involves the transition of a helices into (3 sheet, Gasset et al (1992) examined the physicochemical properties of peptides homologous to residues 109-122,129-141,178-191, and 202-218 of Syrian hamster PrP, which were predicted to correspond to a-helical regions (designated HI, H2, H3, and H4, respectively) by computational studies. At variance with the theoretical predictions, peptides HI, H3, and H4 exhibited extensive (3-sheet structure in the solid state and in aqueous solution and assembled into fibrils showing ultrastuctural and tinctorial properties of amyloid, as described in detail later. Multidimensional het-eronuclear NMR has revealed that the prediction of the two C-terminal... 

With the exception of TSD, lipid data are scarce in the literature for the various forms of amaurotic family idiocies, and the subclassification as outlined is mainly based on clinical and histochemical differences. Since tinctorial properties of a chemical compound are much more dependent on the physico-chemical state than on the concentration (Hagberg et al. 1965), histochemistry is limited to qualitative studies and does not allow a quantitation of lipid storage. 

The improvement in the intrinsic comfort of these fibers is obfained by copolymerization with comonomers in order to improve certain properties. Thus, the increase in the capability of water absorption can be obtained by copolymerization of acrylonitrile with a hydrophilic monomer (acrylic acid, hydroxyethyl acrylate, etc.). Tinctorial properties are improved by incorporation of monomers that decrease the crystallinity and bring chemical functional groups interacting with the dyes (ester functions, etc.) and so on. 

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