Digital Jet Printing Process For High-Grade Wool Fabrics

With the continuous development of China's economy, China has become the largest producer of wool textiles in the world.

(1) small batch: as high-grade clothing and fabrics, printed wool fabrics are mainly produced according to the needs of fashion clothes, and there are many changes in flower pattern design to reflect the personalized requirements of small batch production fashion.

At present, the most advanced screen printing machine is suitable for the high-speed operation of high production production. For small batch of woolen printing processing, it has to go through the process of pattern design, manuscript drawing, net making and so on, not only for long processing time, but also for low cost.

At the same time, the general printing enterprises do not have the conditions for finishing and finishing woollen fabrics.

This limits the production of printed wool fabrics.

(2) fabric is expensive: as the object of printing, wool fabrics are much more expensive than other fabrics.

In screen printing, to achieve the accuracy of the multicolored pattern, it is possible to cause fabric waste of up to 5 meters, which is very evident in high-speed screen printing machines.

It is more serious in complex printing technology, such as discharge printing.

Therefore, the waste in processing and the small volume make it difficult to improve the output of printed wool fabrics.

However,

Fabric preparation for digital jet printing of wool fabrics

In the preparation of fabric before spraying, chlorination plays a very important role in the quality of inkjet printing.

Chlorination can not only increase the depth of inkjet printing, improve the uniformity of inkjet printing, and the brightness of jet printing patterns, but also improve the clarity of patterns and prevent the deformation of patterns in subsequent processing due to the shrink proof effect caused by chlorination.

The chlorination of wool can be continuously processed by wool or continuous processing of cloth, such as continuous production of KroyUnshrinkableWoolLtd., but it does not have such conditions for printing enterprises or even most of the wool textile dyeing and finishing enterprises.

The other way is to use chlorine release agent two sodium chloroisocyanurate (DCCA) gap processing.

Either way, chlorination destroys the scale structure on the surface of wool, increases the hydrophilicity of the wool surface, improves the spreading uniformity of the dye paste or jet ink on the wool surface, and improves the dye uptake rate and dye uptake of the dye on the wool during the steaming process.

Chlorination is usually carried out under acidic conditions. Complex chemical reactions, such as tyrosine oxidation, N chloramine formation, peptide bond cleavage reaction, and so on, have taken place.

These chemical reactions produce many strong anionic groups, accompanied by the breakage of two sulfur bonds and peptide bonds.

Chlorination should be well controlled, otherwise the wool fabric will become yellowed.

Style damage and strength damage.

For fabrics that require bright colors or white spots, they can be bleached. They can be treated by oxidation or reduction.

After the chlorination of wool fabric, the apparent color depth has been improved obviously. The reason is that the scale of wool can be removed by chlorination, so that the polarity and accessibility of wool can be increased, so that the wool can be easily wetted and expanded. The absorption capacity of dye can be greatly increased, and the color depth of printing can be increased. After the addition of chlorination and bleaching, the apparent color depth is increased. This is because the whiteness of the fabric is increased after whitening, which is conducive to light reflection, thus increasing the K/S value.

It can be seen from the above test results that the color depth of wool fabric can be effectively improved by chlorination and bleaching after pretreatment.

{page_break}

Two, wool fabric digital jet printing ink.

The ink used for digital jet printing of wool fabrics is not widely available at present.

It is mainly acidic ink or active ink produced by some large foreign companies. The choice of ink is based on the depth of color, color, color fastness and adaptability to sprinklers.

Three. Pre processing technology for wool fabric digital jet printing pretreatment process:

Mixing slurry -- dip rolling -- drying -- into rolls

(1) selection of paste

In order to prevent the dyestuff from spraying onto the fabric, maintain the clarity of the inkjet pattern and obtain a certain amount of apparent color, the general method is to dip or scrape a certain amount of paste on the fabric.

(2) selection of acid releasing agents

After adding different acid releasing agents, the clarity did not change significantly, and the apparent color depth increased slightly.

(3) the effect of hygroscopic agents on the printing effect.

The moisture absorption agent such as urea added in the pretreatment agent can play the role of moisturizing and promoting the expansion of the fabric during the steaming process, and is conducive to the diffusion of dye from the slurry to the fiber. From Fig. 1, it can be seen that the change of the concentration of hygroscopic agent has a more significant effect on the color depth of C (Qing), M (Pin Hong), Y (yellow) and K (black) four color printing, thereby increasing the color depth and brightness. When the urea concentration increases to a certain degree, the clarity of the printing decreases.

(4) the influence of rolling rate

From the above test results, it can be seen that the change of the rate of rolling within a certain range has no obvious effect on the apparent color depth of printing.

Four. Digital jet printing process for wool fabrics

In addition to woolen sweaters and a small amount of woollen fabrics, most of the woolen fabrics with printing processing requirements are light and fine worsted fabrics, such as those made of clothing, women's clothing and wow.

To complete the design of the computer and complete the jet printing by computer, it is necessary for the worsted dyeing and finishing factory to complete the processing of the entire printed wool fabric.

The general process flow is as follows: raw repair - singeing - (single tank boiling) (light down) - wash it - boiling - chlorination - bleaching - water absorption - drying - Spray - Printing - steaming - washing - water absorption - drying - intermediate inspection - Repair - brush - shearing - steamed - finished products.

Five. Conclusion

(L) digital jet printing is suitable for small batch printing of high-grade wool fabrics.

The design is exquisite.

The strong sense of individuality is an important direction for the development of digital inkjet printing technology in the future.

(2) as a fabric preparation for digital jet printing of wool fabrics, chlorination can significantly improve the depth, brightness and clarity of jet printing patterns.

(3) pretreatment, thickener and hygroscopic agent.

The factors such as acid releasing agent have obvious effect on the printing effect. The jet printing product processing of wool fabric should also be considered with the whole dyeing and finishing process. It will not only affect the printing effect but also affect the high-grade style of wool fabric.