Fiber Dyeing

PACKAGING - CONTAINERS FORINDUSTRIAL MATERIALS] (Vol 17) Fiber-dye property requirements... 

Uses. Most apphcations of MSC are for intermediates in the pharmaceutical, photographic, fiber, dye, and agricultural industries. There also are miscellaneous uses as a stabdizer, catalyst, curing agent, and chlorination agent. 

Although designed to color the fiber, dyeing operations also impart large amounts of permanent set to wool. 

Solubilized vat Cotton, wool, cellulose, and protein fibers silk Impregnated fiber when treated with an oxidized agent usually sulfuric acid and sodium nitrite for cotton dichromate wool and silk therefore, no alkali is involved. This class is applicable to cellulose and protein fibers Dyeing, printing and wool in fast shades... 

Cellulose triesters, moisture properties of selected, 5 416t Cellulose trinitrate, 5 396 Cellulose valerate(s), 5 419 moisture properties, 5 416t Cellulose x, 5 373, 378-379 8 21 Cellulose xanthate, 4 716 5 383 20 559 Cellulosic-acrylic fibers, dyeing, 9 201-202 Cellulosic fiber blends, dyeing, 9 199-202 Cellulosic fiber—nylon blends, dyeing, 9 202 Cellulosic fibers, 18 96... 

Elastic recovery, 19 744 in olefin fibers, 11 227—228 Elastic scattering, 24 88-89 Elastic springs, in virtual two-way SMA devices, 22 346-347 Elastic waves, 17 422 Elastohydrodynamic (EHD) lubrication regime, 15 211-212 Elastomer-coated dies, in bar soap manufacture, 22 752 Elastomer designations, ASTM, 9 552t Elastomeric fibers, dyeing, 9 204 Elastomeric polycarboranylsiloxanes,... 

Synthetic organic pigments, 19 418-422t history of, 19 423-424 Synthetic organic polymers, manufactured fibers based on, 24 616-618 Synthetic polyamide fibers, dyeing, 9 188-191, 469-470... 

During polymerization, PDO dimerizes into dipropylene ether glycol (DPG) which incorporates into the PTT chains as a copolymer. DPG formation is more severe in the acidic TPA process. The incorporated DPG lowers the polymer s melting point and affects fiber dye uptake [34],... 

The most economically important materials with respect to ozone damage are paint, elastomers (rubbers), and textile fiber-dye systems. Damage to polyethylene by ozone is considered to be negligible. The 1970 ozone damage to materials has been estimated as follows paint, 540 million elastomers, 569 million and textile fibers and dyes, 84 million—for a total of over 1 billion. Thus, the total combined material and crop damage falls between 1.5 and 2 billion per year. Estimates of damage to natural ecosystems are not available. 

Modem civilization consumes vast quantities of organic compounds. Coal, petroleum, and natural gas are primary sources of carbon compounds for use in production of energy and as starting materials for the preparation of plastics, synthetic fibers, dyes, agricultural chemicals, pesticides, fertilizers, detergents, rubbers and other elastomers, paints and other surface coatings, medicines and drugs, perfumes and flavors, antioxidants and other preservatives, as well as asphalts, lubricants, and solvents that are derived from petroleum. 

Fiber and particulate residues, archaeological textiles by infrared techniques, 44-77 Fiber charring, 49-50 Fiber dyeing, 51 Fiber mineralization, 51 Field analysis by XRF, obsidian sources in Central Pet6n, Guatemala, 506-521 Fish Slough Cave, Owen s Valley, California, population movement studies, 80... 

Reactive dyes are well suited to dye blends of cellulose and PA fibers. Clear shades with very good fastness are obtained. Like with vat dyes, the depth of shade of reactive dyes depends relatively strongly on the type of PA and structural differences. Dyeing is carried out in a three-step process with appropriately selected products. First, the reactive dyes in a weakly acidic liquor are allowed to absorb on the PA component. Salt is then added to improve the yield on the cellulose component. Finally, the liquor is made alkaline for reaction with the cellulose fiber. Dyes (e.g., with MTC anchor) that dye PA from a neutral liquor in the presence of salt are applied in a two-step process, as in the case of cellulose. In the reversal of this dyeing process, the cellulose component is dyed first at alkaline pH, followed by neutralization with acid, and the PA component is then covered at elevated temperature. 

Bonding Forces Between Dye and Fiber. Dye anions can participate in ionic interactions with fibers that possess cationic groups. However, the formation of ionic bonds is not sufficient to explain dye binding, because compounds that can dissociate are cleaved in the presence of water. Secondary bonds (dispersion, polar bonds, and hydrogen bonds) are additionally formed between dye and fiber [47], Close proximity between the two is a prerequisite for bond formation. However, this is counteracted by the hydration spheres of the dye and of wool keratin. On approach, these spheres are disturbed, especially at higher temperature, and common hydration spheres are formed. The entropy of the water molecules involved is increased in this process (hydrophobic bonding). In addition, coordinate and covalent bonds can be superimposed on secondary and ionic bonds. 

Another classification is based on covering up material differences in textured PES fibers. Dyes that have a low fastness to thermo fixing often hardly mark differences in texture they dye at relatively low temperature and are suited to carrier dyeing processes. Dyes that are very fast to thermofixing diffuse slowly into the fiber and must be dyed at high temperature they are not suited for carrier dyeing under atmospheric pressure they tend to mark texture and fixing differences in the fiber. 

Modified PES fibers are usually more sensitive to hydrolysis than normal fibers. The lightfastness of the dyeings is often lower than on normal fibers. Thus, dyes for coloring carpeting, upholstery, and drapery must be carefully selected. On modified PES fibers dyes start exhausting at low temperatures (ca. 60°C) and the dyebath is exhausted after a short time, so problems with levelness may arise. 

Elastomeric polyurethane fibers [96, pp. 609-615], are contained in stretch articles and in knitted fashion materials. Light shades can be dyed tone-on-tone on polyamide-polyurethane mixtures with disperse dyes at 95-98°C and pH 6-7. However, the wetfastness of these dyeings on polyurethanes is lower than on polyamide. Because of the temperature sensitivity of polyurethane fibers, mixtures of elastomeric and polyester fibers must be dyed with small-molecular, rapidly diffusing disperse dyes in 30 min at 120 °C according to the HT process [148], Modified PES fibers that are dyeable at 100°C without a carrier are often used in mixtures with elastomeric fibers. In all dyeing processes for elastomeric fibers, dyeing equipment that permits low-strain guidance of the material and the lowest possible thermal stress are important. 

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