Dyeing textile fibers synthetic

Phthalocyanine Dyes. In addition to their use as pigments, the phthalocyanines have found widespread appHcation as dyestuffs, eg, direct and reactive dyes, water-soluble dyes with physical or chemical binding, solvent-soluble dyes with physical or chemical binding, a2o reactive dyes, a2o nonreactive dyes, sulfur dyes, and wet dyes. The first phthalocyanine dyes were used in the early 1930s to dye textiles like cotton (qv). The water-soluble forms Hke sodium salts of copper phthalocyanine disulfonic acid. Direct Blue 86 [1330-38-7] (Cl 74180), Direct Blue 87 [1330-39-8] (Cl 74200), Acid Blue 249 [36485-85-5] (Cl 74220), and their derivatives are used to dye natural and synthetic textiles (qv), paper, and leather (qv). The sodium salt of cobalt phthalocyanine, ie. Vat Blue 29 [1328-50-3] (Cl 74140) is mostly appHed to ceUulose fibers (qv). 

Sulfur dyes are used mainly for dyeing textile ceUulosic materials or blends of ceUulosic fibers (qv) with synthetic fibers such as acryUc fibers, polyamides (nylons), and polyesters. They are also used for sHk (qv) and paper (qv) in limited quantities for specific appHcations. Solubilized sulfur dyes are used on certain types of leathers (qv). 

Mordant Dyes. This group includes many natural as well as synthetic dyes. They have no or low substantivity for textile fibers and are therefore appHed to ceUulosic or protein fibers that have been treated (mordanted) with metallic oxides to give points of attraction for the dye. The dye... 

To facilitate an overview and to consider the specific differences of textile fibers during pretreatment, dyeing, and finishing, the sections have been focused on the most important types of fibers wool, cotton, and synthetic fibers. Mixtures of fibers can be seen as systems combining problems of the single fiber types. In Section 8.3 end-of-pipe technologies have been summarized. 

The world textile industry is one of the largest consumers of dyestuffs. An understanding of the chemistry of textile fibers is necessary to select an appropriate dye from each of the several dye classes so that the textile product requirements for proper shade, fastness, and economics are achieved. The properties of some of the more commercially important natural and synthetic fibers are briefly discussed in this section. The natural fibers may be from plant sources (such as cotton and flax), animal sources (such as wool and silk), or chemically modified natural materials (such as rayon and acetate fibers). The synthetic fibers include nylon, polyester, acrylics, polyolefins, and spindex. The various types of fiber along with the type of dye needed are summarized in Table 8.2. 

Reactive dyes were introduced at the end of the 1950s. These synthetic dyes consist of a two-part, direct coloring agent. The first moiety is a chro-mophore with an azo, anthraquinone, or phthalocya-nine derivative structure. This moiety is connected to a second reactive group, which is able to form covalent bonds with the amine or sulfhydryl groups of proteins in the textile fibers (Figure 21). The main... 

Use Manufacture of kraft paper, paperboard, and glass filler in synthetic detergents sodium salts ceramic glazes processing textile fibers dyes tanning pharmaceuticals freezing mix laboratory reagent. food additive. 

Textiles. In the area of textile and synthetic fiber processing, amine oxides have been used as dyeing auxiUaties as well as wetting agents (51,52), as antistatic agents (qv) (53—55), and as bleaching agents (56,57). 

The popularity and widespread use of azo dyes is due to several factors [1]. As a group, th are colour-fast and encompass the entire visible spectrum, and many are easily S3mthesized from inexpensive and easily obtained starting materials. Azo dyes are also typically amenable to structural modification, and representative azo dyes can be made to bind most synthetic and natural textile fibers. 

Ammonia is required for the synthesis of ammonium salts and certain alkalies, dyes, pharmaceuticals, synthetic textile fibers, and plastics. 

Polyvinylpyrrolidone is thus utilized as either aqueous or organic solutions in a multitude of applications. Many of these applications are also related to the chelating properties of this polymer. Thus, it forms complexes with molecular iodine (I2) and can thus be used as a reservoir of this molecule whose disinfecting properties are well known. It also gives strong interactions with natural and synthetic dyes and thus facilitates their anchoring on textile fibers by complexation with the corresponding polymers. 

The major part of the production of PET is utilized for the manufacture of textile fibers. Their annual world production is about 18 million tons, which corresponds to two-thirds of the production of synthetic textile fibers. These fibers are used either alone or mixed with cotton or wool. However, the tinctoriability of PET fibers is low and, in a pure state, dyeing is obtained by dispersion of the dye in amorphous zones of the semicrystalline material. Another solution to solve this problem involves replacement of pure PET by various copolymers that introduce reactive functional groups along the chains simultaneously with the reduction of the degree of crystallinity the latter point is detrimental to the mechanical properties. 

Sulfonic Acid-Based Dyestuffs. Sulfonic acid-derived dyes are utilized industrially in the areas of textiles (qv), paper, cosmetics (qv), foods, detergents, soaps, leather, and inks, both as reactive and disperse dyes. Of the principal classes of dyes, sulfonic acid derivatives find utiUty in the areas of acid, azoic, direct, disperse, and fiber-reactive dyes. In 1994, 120,930 t of synthetic dyes were manufactured in the United States, of which 5,600 t were acidic (74). The three largest manufacturers of sulfonic acid-based dyes for use in the United States are BASF, Bayer, and Ciba-Geigy. 

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