Here are some auxiliaries used in polyester dyeing:
Carriers
These include o-phenyl phenol, p-phenyl phenol, diphenyl, monomethyl naphthalene, trichlorobenzene, dimethyl terephthalate, and methyl salicylate.
Disperse dyes
These are polar molecules that contain anthraquinone or azo groups. They are practically insoluble in water, so dispersing agents are used to keep them dispersed in water.
Leveling agents
These include ethoxylate or propoxylate of substituted phenol, emulsifier, and carrier.
Other auxiliaries used in polyester dyeing include:
Halogenobenzenes, Halogenotoluenes, N-alkylphthalimides, Aromatic carboxylic esters, Methylnaphthalene, Diphenyl ethers, Naphthol ethers, Phenol ethers, and Hydroxydiphenyls.
Polyester is dyed using disperse dyes in an acidic medium at 120°C or 130°C.
The textile dyeing and finishing industry serves other textile and apparel industries by converting rough and unattractive loom fabrics into products with enhanced color, appearance, feel and performance suitable for end uses. Facing global competition, textile printing and dyeing companies are now constantly striving to improve market competitiveness and streamline printing and dyeing operations to increase profits.
Now, right-first-time dyeing is critical to staying cost-competitive and maximizing machine utilization and throughput. While modern dye formulations are complex and structured to provide high performance on dyed and subsequently dyed fabrics, the requirements for obtaining correct first dyeing impose higher demands that cannot be met by dye formulation alone. Modern dyers are fortunate to be able to rely on a wide range of dyeing chemicals (often called auxiliaries or dyeing auxiliaries) to facilitate exhaust and continuous dyeing operations and to create optimal dyebath conditions for one-time dyeing.
Increasingly highly automated low liquor ratio exhaust dyeing machines require the use of disposable, multifunctional liquid additives that can be poured or pumped into the machine. Versatility reduces the amount of product that needs to be purchased, stored, and weighed or dispensed, and reduces the volume of liquid that must be added to the machine. Concentrated liquid auxiliaries can also be transported and stored in less space, which is a benefit for both chemical suppliers and textile dyers. Based on extensive research and development, chemical suppliers optimize the versatility of their auxiliaries for use in dyebaths. Disposable multifunctional auxiliaries therefore offer many technical and practical advantages to textile dyeing plants
In the exhaust dyeing of polyester and polyester/cellulose yarns and fabrics, it is very important to use non-foaming auxiliaries, especially in jet dyeing. In addition, the high-temperature dyeing conditions used place many requirements on the dispersion properties of disperse dyes in the dye liquor. Clariant has launched Eganal PLM liq, a multifunctional non-foaming dyebath auxiliary that not only has dispersion and diffusion-accelerating properties, but also migration-promoting properties. Improved dyebath dispersion stability is essential to prevent aggregation of disperse dyes and their physical deposition on the fiber surface, resulting in poor rubbing fastness. Eganal PLM liq ensures good penetration and improves color yield. Better dye coverage to materials in which different dye affinities may be present may also be achieved by reducing dyeing time and/or dyeing temperature.
Eganal PLM liq can also be used for level dyeing or partial stripping of poor dyeing if this occurs. An important benefit for polyester dyers is that Eganal PLM liq does not adversely affect wet fastness and has minimal or no effect on light color fastness. Additionally, no unpleasant odor is produced during the dyeing or heat drying process compared to some other products used commercially.
