Лако-красочные материалы — производство

Cellulosic fibres are natural fibres derived from plant sources. The most important cellulosic fibres are cotton, viscose, linen, jute, hemp and flax. The principal component of the cotton fibre is cellulose, the structure of which is shown in Figure 7.4. Cotton is in fact almost pure cellulose (up to 95%). Cellulose is a polysaccharide. It […]

Protein fibres are natural fibres derived from animal sources, the most important of these being wool and silk. The principal component of the wool fibre is the protein keratin, the molecular structure of which is illustrated in outline in Figure 7.1. The protein molecules consist of a long polypeptide chain constructed from the eighteen commonly […]

In Chapters 3-6, the commercially important chemical classes of dyes and pigments are discussed in terms of their essential structural features and the principles of their synthesis. The reader will encounter further examples of these individual chemical classes of colorants throughout Chapters 7-10 which, as a complement to the content of the earlier chapters, deal […]

The nitro group is commonly encountered as a substituent in dyes and pigments of most chemical classes, but it acts as the essential chromo — phore in only a few dyes. Nitro dyes are a small group of dyes of some importance as disperse dyes for polyester and as semi-permanent hair dyes. Picric acid, 139, […]

Sulfur dyes are a group of low cost dyes used in the coloration of cellulosic fibres. The dyes are fairly small in number although some of the individual products are manufactured in very large quantities. They are capable of providing a wide range of hues although they tend to give rise to rather dull colours, […]

Dioxazine colorants, as the name implies, contain two oxazine ring systems as the chromophoric grouping. They are relatively few in number and generally restricted to violet to blue shades. Probably the most important dioxazine colorant is C. I. Pigment Violet 23, 136. This prod­uct is usually referred to as Carbazole Violet and is the most […]

Arylcarbonium ion colorants were historically the first group of synthetic dyes developed for textile applications. In fact, Mauveine, the first com­mercial synthetic dye, belonged to this group (Chapter 1). The majority of the arylcarbonium ion colorants still in use today were discovered in the late 19th and early 20th centuries. As a group they are […]

Polyene and polymethine dyes are two structurally related groups of dyes which contain as their essential structural feature one or more methine (-CH-) groups. Polyene dyes contain a series of conjugated double bonds, usually terminating in aliphatic or alicyclic groups. They owe their colour therefore simply to the presence of the conjugated system. In polymethine […]

The chemistry of the three most important chemical classes of organic colorants, the azo, carbonyl and phthalocyanine classes, has been dealt with individually in Chapters 3 -5 respectively. In this chapter, the chem­istry of a further five chemical classes which are of some importance for specific applications is discussed. These classes are the polymethines, arylcarbonium […]

The synthesis of metal phthalocyanines requires, essentially, the presence of three components: a phthalic acid derivative, such as phthalic anhydr­ide, phthalimide, phthalonitrile or o-cyanobenzamide, a source of nitro­gen (in cases where the phthalic acid derivative does not itself contain sufficient nitrogen) and an appropriate metal derivative. Commonly the reaction requires high temperatures and may be […]