Silk printing technology example analysis

The silk can be pretreated with a synthetic denaturant such as melamine, paraformaldehyde and polyethylene glycol together with a softener, and then transferred with a disperse dye.

Test Example: The refined, bleached real silk dip two finishing finishing bath, the liquid rate of 90%. The finishing bath consists of the above synthetic resin, catalyst and softener. The fabric sample was dried at 90°C for 3 minutes, and then transferred with a manual transfer printing machine at 190°C for 1 minute. The printing process consists of slurring Indalca AGBV glue (6%) in cold water. The transfer paper was manually scraped twice with a screen and dried at room temperature. Printing paste composition: 4 parts of disperse dyes, 7.5 parts of anionic additives, 88.5 parts of Indalca gum (6%), a total of 100 parts.

The relevant parameters are discussed below:

(1) Effect of resin concentration: The percentage of dye transfer increases with the increase of the resin concentration, but it exceeds 200g/L, with little increase. The more suitable resin formulation is: 200g/L of the above synthetic resin, MgCl2·6H2O 10g/L, After padding, the sample was dried at 90°C for 3 minutes and then transferred at 190°C. The tested CI Disperse Violet 1, CI Disperse Red 1, and CI Disperse Orange 3 printed samples had satisfactory washing fastness, but they had good dry-clean fastness, indicating that the fiber and the resin could form a large amount of cross-linking. Dry-cleaning solvents do not penetrate fibers and extract dyes.

(2) Fiber-resin-dye interactions: Early studies showed that dyes containing -NH2 groups react more readily with resins, dyes with -NHCH2-OH are moderately reactive, and dyes without these groups do not reaction. The same results were obtained with the above test, that is, CI Disperse Violet 1 and Disperse Orange 3 exhibited greater reactivity than CI Disperse Red 1 .

(3) Real Silk Finish: Synthetic resin imparts wrinkle resistance to silk while transferring printing.

(4) Catalysts and softeners: In the three catalysts of magnesium chloride, zinc nitrate, and sulfamic acid, the phenomenon of yellowing with magnesium chloride is less. Adding a softening agent to the rolling bath helps improve the feel of the printed fabric and improves the breaking strength, tear strength and abrasion resistance of the silk. Among different softeners, yellowing is most severe with anionic and cationic types, while yellowing with polyethylene emulsions is less. The softener concentration increased from 15g/L to 50g/L, which had little effect on the wrinkle recovery angle, bending length and yellowness index. The yellowness index of polyethylene emulsion increased with the increase of the concentration. The non-ionic softener in the rolling bath has a slightly better effect on the wrinkle recovery angle and bending length of the finishing fabric than other softeners.

(5) Weight gain of silk: The method of pretreating the silk with the above-mentioned synthetic resin can obtain a weight gain of 14%, but the weight increase depends on the resin concentration and the wet weight increase during the padding process.