Dyeing properties

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

These acid rhodamines are usually used for sHk and wool because they have level dyeing properties and show good fastness to alkaU however, they have poor lightfastness. An improved process for manufacturing 3,6-diaminosubstituted xanthenes is reaction of the inner salts of... 

There is a wide variety of dyes unique to the field of hair coloring. Successive N-alkylation of the nitrophenylenediamines has an additive bathochromic effect on the visible absorption to the extent that violet-blue dyes can be formed. Since the simple A/-alkyl derivatives do not have good dyeing properties, patent activity has concentrated on the superior A/-hydroxyalkyl derivatives of nitrophenylenediamines (29,30), some of which have commercial use (31). Other substituents have been used (32). A series of patents also have been issued on substituted water-soluble azo and anthraquinone dyes bearing quaternary ammonium groups (33). 

The color and constitution of cyanine dyes may be understood through detailed consideration of their component parts, ie, chromophoric systems, terminal groups, and solvent sensitivity of the dyes. Resonance theories have been developed to accommodate significant trends very successfully. For an experienced dye chemist, these are useful in the design of dyes with a specified color, band shape, or solvent sensitivity. More recendy, quantitative values for reversible oxidation—reduction potentials have allowed more complete correlation of these dye properties with organic substituent constants. 

A wide variety of stmetures exist in the cyanine, merocyanine, and oxonol classes of dyes. Properties that may affect toxicity vary widely also. These include solubihty, propensity to be oxidized or reduced, aggregation tendency, and diffusion through membranes. Specific acute toxicity data are Hsted in Table 2, and the LD q data vary widely with the test used. 

K. Tandy, Jr., "Characteristics of Polyester Homopolymer Fiber Which Affect Dyeing Properties," paper presented at the 14th yLATCC JS ew England Kegional Technical Conference, New Hampshire, May 19—21,1977. 

Anth nthrones. Halogenated derivatives have been developed to improve the dyeing properties of anthanthrones, which have low tinctorial strength and poor affinity to cellulose fibers. The only example of commercial significance is Cl Vat Orange 3 [4378-614] (4) Cl 59300). This compound is prepared from l,l -dinaphthyl-8,8 -dicarboxyhc acid (173) with oleum and bromine as follows ... 

The 1 2 metal complex dyes are dyed either at neutral pH or with ammonium acetate, and the exhaustion achieved by the effect of van der Waals forces. The pH is then aUowed to go slightly acidic to form salt linkages between the dye anion and the protonated primary amine groups in the wool (NH3 ). AU the dyes have similar dyeing properties and the conditions of appHcation do not damage the wool. 

Pure polymeric acrylonitrile is not an interesting fiber and it is virtually undyeable. In order to make fibers of commercial iaterest acrylonitrile is copolymerized with other monomers such as methacrylic acid, methyl methacrylate, vinyl compounds, etc, to improve mechanical, stmctural, and dyeing properties. Eibers based on at least 85% of acrylonitrile monomer are termed acryHc fibers those containing between 35—85% acrylonitrile monomer, modacryhc fibers. The two types are in general dyed the same, although the type and number of dye sites generated by the fiber manufacturing process have an influence (see Eibers, acrylic). 

Although there is still demand for indigotin for dyeing blue jeans, it has lost a good part of the market to other blue dyes with better dyeing properties. At present, practically all the indigotin consumed in the United States comes from abroad. 

Farbechtheit, /. color fastness. Farbeeigenschaft, /. coloring (or dyeing) property. 

TREATMENTS TO ALTER DYEING PROPERTIES OR ENHANCE FASTNESS 667... 

Only the products associated with acid and premetallised dyes are dealt with in this section. The auxiliaries used with mordant dyes are covered in section 5.8. Anionic acid dyes, applied principally to wool and nylon, vary widely in their fastness and level-dyeing properties (section 3.2.2) in general, the higher the wet fastness of a dye the more difficult it is to apply evenly. Hence it is not surprising that the use of auxiliaries with acid dyes is related mainly to level-dyeing properties. There are two basic aspects ... 

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