The production of printing and dyeing auxiliaries in China has progressed with the development of the textile printing and dyeing industry. Since the 1990s, the development of new fibers, the innovation of textile technology, the improvement of consumption levels and the increase in exports have forced the textile industry to seek new additives and new business models. From the beginning of import to the nationwide research and production, a prototype of the production industry of printing and dyeing auxiliaries intersecting chemical and textile industries has gradually formed. Today, with each passing day, products are developing towards high-end, comfortable, healthy and ecologically green. The development trend of textile printing and dyeing auxiliaries has four major aspects: the development of corresponding auxiliary auxiliaries according to the development of new fibers; the use of compound technology to increase the versatility and high functionality of the auxiliaries; the use of high-tech products to supplement and improve the traditional Textile printing and dyeing auxiliary products; development of environmentally friendly additives. In order to adapt to the new development trend, the textile printing and dyeing industry needs to continuously inject fresh blood to maintain the diversified development of production and operation. In short, the development of printing and dyeing auxiliaries follows an informational high-tech diversified parallel road, which requires us to constantly explore and discover in the way forward in order to achieve higher and better development.
Printing and dyeing auxiliaries include printing auxiliaries and dyeing auxiliaries. Printing auxiliaries include thickeners, adhesives, cross-linking agents, emulsifiers, dispersants and other printing auxiliaries. Dyeing auxiliaries include dyes and levelling agents , Fixing agent, dispersing agent.
Printing auxiliary:
Paint printing is to use the film-forming effect of the adhesive to firmly adhere the insoluble dye to the fabric, so as to achieve the purpose of coloring.
Adhesive is the main component of paint printing paste, which is a polymer film-forming substance. The film is used to adhere the paint to the fabric. Therefore, it is required that the adhesive has a trained adhesion and reproducibility and aging resistance to the fabric. , Resistant to solvents, acids and alkalis, and chemicals. The film is clear and transparent. It does not change color after printing, does not damage the fibers. It has a certain elasticity and a good feel. It can be easily removed from the printing machine.
Thickener is another essential component of paint printing pastes. It has the functions of thickening color dyes, promoting adhesion and emulsification, etc. The right printing fabric obtains a uniform, soft and clear pattern. Not only can the color volume and vividness be trained, but kerosene is not used or used in the printing paste, so as to reduce the air pollution by leap. There are two types of synthetic thickeners, anionic and non-ionic. The former has strong adaptability and can be used for anti-dyeing and dial dyeing printing, but the thickening effect is poor; the latter has high viscosity and thickening effect on printed fabrics. The color brightness, scrubbing fastness and softness of the hand have no adverse effects.
The main function of the cross-linking agent is to improve the fixing ability of the adhesive. The printing has better firmness, and can also reduce the curing temperature. In combination with the actual short curing time, the amount should be appropriate, otherwise it will cause the fabric to feel poor. .
The emulsifier is added to obtain a good emulsifying thickener. Generally, the terminal group-blocked alkylphenol polyoxyethylene ether is used, and then the terminal group is blocked with isocyanate.
Paint printing auxiliary agents also include softeners, diffusion agents and defoamers.
Scouring aids:
Fabric desizing, scouring, bleaching and mercerizing are all important processes before fabric printing and dyeing, and are collectively called scouring. Scouring is to boil desizing cotton fabric in 10g / L dilute caustic soda solution for several hours to remove impurities such as cottonseed shell, wax, pectin, nitrogen-containing substances and pigments on cotton fiber and residue The slurry on the cloth to obtain a good appearance and its water absorption performance, effectively improve the printing and dyeing and finishing effects.
Synthetic fibers do not need scouring, but blended fabrics with cotton fibers still need to be scouring, but soda ash should be used instead of caustic soda, and a less concentrated aromatic caustic soda solution should be used. Certain surfactants need to be added to the scouring liquid to increase the permeability of the lye, promote the emulsification of waxy substances, and further disperse the impurities leaving the fiber in the scouring liquid.
Dyeing aid:
Dyeing agent, dyeing is the main part of the dyeing process. Different fiber fabrics use different colorants, and according to different processes, the dye processing aids include solvent aids, dispersants, color developers and phthalocyanine additives. The dyes used in dyeing are not direct dyes, vat dyes, reactive dyes, phthalocyanine dyes and insoluble azo dyes.
Leveling agent, leveling agent is natural fiber leveling agent, synthetic fiber leveling agent and blended fabric levelling agent, etc., as a leveling agent, the dye can be slowly absorbed by the fiber or the dark part of the dye lighter The color part spreads without reducing the dyeing fastness. All auxiliaries with retarding and migration effects are called levelling agents.
There are three types of fixing agents, cationic surfactants, non-surface active quaternary ammonium salts, and resin-based fixing agents. The fixing agent will cause the dye to form a water-insoluble dye salt or make the dye molecule Increased and difficult to dissolve in water, thereby improving the firmness of dyeing.
Dispersant, dispersant is an indispensable auxiliary agent in dye processing and dye application. It can disperse the dye particles up to about 1μm, which helps to crush the particles and maintain the dispersion stability of the dye. Agents, including anionic, cationic, non-ionic, amphoteric and polymeric.
Fluorescent whitening agent, fluorescent whitening agent referred to as FWA, it uses the optical complementary color effect to make the yellow-brown pigment on the fabric that cannot be removed by chemical bleaching become white. Due to the enhanced brightness, the whiteness is more beautiful.