Sublimation fastness

Dyes with good wet. light, and sublimation fastness for polyesters, nylon, and acetate fibers... 

Substitution by chloro, nitro, and similar groups iacreases the molecular weight and improves sublimation fastness but lowers the oil solubiUty of this group of dyes. 

Cl Disperse Blue 73/72222-75-2] Cl 63265) is an example of a dye that was developed to improve sublimation fastness for special use, eg, thermosol dyeing or printing. This dye also has a bright shade, excellent lightfastness and good leveling properties. Cl Disperse Blue 73 (113) is prepared as follows, where R = H or CH,. 

A Substituted-l-Amino-4-hydroxyanthraquinones. These dyes show good affinity and hghtfastness and give violet to blue shades. However, the sublimation fastness is in general not satisfactory. An example is Cl Disperse Blue 72 [81-48-1] (117) (Cl 60725), prepared from leucoquinizarin and -toluidine. 

Suitable disperse dyes for polyester require good sublimation fastness and generally contain additional or more hydrophobic substituents compared with acetate dyes. Thus, for example, Cl Disperse Red 60 (6.42) is important for the dyeing of polyester fabrics but has only moderate sublimation fastness. It is, however, the most important red dye for transfer... 

Quinophthalone (6.229) and its derivatives [86] also fall into the methine category, although they appear in the Colour Index under quinoline colouring matters. The parent compound was discovered in 1882 by Jacobsen, who condensed 2-methylquinoline (quinaldine) with phthalic anhydride. The product, quinoline yellow, is used as a solvent dye (Cl Solvent Yellow 33). The light fastness is improved by the presence of a hydroxy group in the quinoline ring system. Derivatives of this type provide greenish yellow disperse dyes for polyester. The moderate sublimation fastness of Cl Disperse Yellow 54 (6.230 R = H) is improved by the introduction of an adjacent bromine atom in Cl Disperse Yellow 64 (6.230 R = Br). 

Dyes with aromatic hydroxy compounds as coupling components, of which C.I. Disperse Yellow 3, 11855 [2832-40-8] is a representative example, have long been used to dye acetate fibers. Its use has been questioned for ecological reasons (see Chapter 8). For application to polyesters, sublimation fastness has been enhanced by increasing the size of the molecule. 

Quinophthalone Dyes. Currently, 3 -hydroxyquinophthalone [7576-65-0] is employed extensively in a number of product lines used to dye synthetic fibers in greenish yellow hues with good lightfastness and generally sufficient sublimation-fastness. Suitable substitution in the phthalic acid residue or the quinoline nucleus may improve thermosetting fastness [29], An example is C.I. Disperse Yellow54, 47020 [7576-65-0] (10) ... 

Methine Dyes. The condensation products of 4-dialkylaminobenzaldehydes with cyano acetic esters have long been used to dye acetate fibers. Brilliant greenish yellow dyes with excellent lightfastness are obtained on polyester fibers with the corresponding condensation products of malonodinitrile. The sublimation fastness of this dye type can be improved by introducing suitable substituents into the alkyl residue of the amino group or by doubling the molecular size, e.g., C.I. Disperse Yellow 99, [25857-05-0] (11) [12,30,31],... 

The bathochromic shift from 9 to 11 affects the color the lightfastness increases in the order of 10 to 11 to 9 and the affinity increases from 9 to 11 to 10. The sublimation fastness of all three is moderate. 

The heat (sublimation) fastness increases with the bond strength between polymer and dyestuff and with the sublimation temperature of the dyestuff. 

F or by continuous methods, that is, thermasol or thermafix dyeing methods at temperatures of 375 to 410°F. These dyes possess good sublimation fastness characteristics. Examples of high energy dyes are Disperse Blue 79 and Disperse Red 177 ... 

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