The printing process is a process in which dyes or pigments are used to imprint patterns on textiles. Printing is divided into textile printing, wool top printing and yarn printing, and mainly textile printing. Top printing is used to make mixed-color tweed; yarn printing is used to weave special-style colorful pattern fabrics. Fabric printing has a long history.

Dyeing means to dye the color, also called coloring, which refers to the use of chemical or other methods to affect the substance itself to make it color. Under the conditions permitted by technology, dyeing can make objects show all kinds of colors that people need, and decorate life with colorful colors. The dyeing method has existed since ancient times and is constantly evolving.

Similarities and differences between printing and dyeing

In terms of the mechanism of dyeing fibers with dyes, printing and dyeing are the same, but in printing, a certain color of dye is applied to the part of the textile according to the pattern requirements. After a certain post-treatment, the dye is dyed on the fiber, and then the dye is dyed on the fiber. A printed product with one or more colors is obtained on the textile. Therefore, printing can also be said to be "partial dyeing".

When textile dyeing and printing use the same type of dyes, the chemical auxiliaries used and their physical and academic properties are similar, so their coloring and fixing principles are similar or the same; and for the same type of fiber products, if you use The same dye dyeing and printing can have the same fastness. For example, the fastness of vat dyes is good, and the fastness of printing products is also good.

In printing and dyeing, dye aqueous solution is used for dyeing process, and color paste is used for printing. Color paste is a paste with a certain viscosity adjusted by adding paste to the dye solution or dispersion.

Its use can prevent the unclear pattern outline, distortion of the pattern and dye migration during post-printing drying caused by the infiltration of the pattern during printing; the concentration of dyes and chemical additives in the color paste is higher than that in the general dye bath. It is much higher, coupled with a large amount of paste, which makes it difficult to dissolve the dye. Therefore, a cosolvent such as urea, alcohol, etc. should be added to the printing paste; when dyeing, the dye penetration and diffusion are sufficient, and the dye is in the paste during printing, and it is not easy to diffuse and penetrate. Therefore, after printing, steaming or baking must be used to increase the diffusion rate of the dye to help dye the fiber.

Printing VS Dyeing

If color matching is required during dyeing, the general requirement is that the same type of dyes are used for color matching, and for printing, several different types of dyes can be used for common printing on the same textile, such as: coating and insoluble azo dyes, reactive dyes and reactive dyes. Simultaneous printing of insoluble azo dyes, simultaneous printing of reactive dyes and fast sulfonates, simultaneous printing of insoluble azo dyes and polycondensation dyes, etc. Sometimes different types of dyes can be used in the same color paste for the same printing;

Such as: paint and insoluble azo dyes in the same slurry, disperse dyes and reactive dyes in the same slurry, etc., so that between the dye and the dye, the auxiliary Have a very in-depth understanding of characteristics, use the contradiction and compatibility between dyes and auxiliaries to serve the products, and print some special style printing products.

Dyeing VS printing

The dyes used in printing and dyeing are roughly the same, but there are also some dyes specifically used for printing, such as reactive dyes for printing (domestic P-type reactive dyes, etc.), stable insoluble azo dyes, temporary soluble dyes, etc.; there are white flowers or The white ground is required to be very white, which requires that the semi-products after pretreatment are similar to bleached cloth. After printing, bleaching water is generally required, and the dyed cloth is especially dyed with deep and dense colors. The pretreatment can not be bleached; the printed cloth cannot have weft skew, especially It is for patterns such as lattice, horizontal strip, square or characters, and strict requirements for the weft of semi-finished products; there should also be certain requirements for the width of the cloth, so as to avoid flower slanting and patterns on the cloth when stenting after printing The deformation of dyed cloth is not as strict as that of printed cloth.

For printed semi-products, the hair effect should be uniform and have a good "instantaneous hair effect", mainly because the dye has a short action time during printing, and the printed pattern is required to have uniform color, clear outline, smooth lines, and no broken threads. Therefore, every step of the pre-processing of printed fabrics is very important.Only by obtaining good quality of the semi-products can the printing quality be guaranteed.Therefore, the pre-treatment requirements of the printed semi-products are higher than that of the dyed semi-products; the concealing printing of the gray fabric defects is better than Good dyeing, especially some disordered patterns, can effectively conceal some fabric defects.

In short, for colored textiles, dyed products require uniform and full color, bright and transparent core, while printed products require bright and generous patterns, national characteristics, clear flower outlines, fresh white flowers, and full color. It is an artistic industry. product.