Flat screen printing common defects and prevention

Some common defects and their preventive measures in flat screen printing:

1. It is forbidden to remove or overlap one or more colors in all or part of the pattern on two or more sets of printed fabrics.

Measures:

(1) The patch should be flat and secure. The paste on the surface of the rubber tape must be evenly distributed, uniform in thickness and moderate in viscosity to achieve the requirements of “stickiness, thinness, and uniformity”, which is conducive to the accuracy of flowers.

(2) Thoroughly clean the rubber belt. The paste paste and print paste on the surface of the rubber tape are washed thoroughly and thoroughly, keeping it clean and flat, which is beneficial to the next flowering cycle.

(3) Reasonably arrange the screen printing sequence. From the perspective of flowering, pattern screens with relatively close relation to flowers should be arranged in adjacent positions. Because the fabric absorbs printing paste, it will cause shrinkage, especially the pattern with larger amount of suction, the amount of shrinkage will be larger, the farther the printing screen is apart, the more color paste will be printed on the fabric with other patterns. At the same time, the amount of shrinkage of the fabric is increased, resulting in difficulty in flowering.

2, paste (spray, osmotic) The fabric shows the outline of the pattern is unclear, the pattern around the rough, not clean, color and color between the leaking, fat flower paste, and the original is inconsistent.

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Measures: Before the printing, the semi-finished products must be dried. The viscosity of the printing paste is moderate, and the lifting and moving of the printing screen are in a constant position. When the printing is done, it can be completely repeated in the original position, so as to ensure a good reproduction. Sex, to ensure that the outline of the pattern is clear.

3. Fine stems, white stems, etc. of pressure pattern marks are pressed and paste by the printing net frame, or the pressure is uneven and not even, and fish scales will be produced.

Measure: When printing, handle two screen plates to prevent overlap. If it is the relationship of the flower structure, it will bring difficulties to the open edition. If the original pattern is not affected, the pattern can be interleaved with the pattern of the large floor and other patterns can be appropriately extended to prevent it from adhering. A horizontal line overlaps at the opposite ends of a screen. For large surfaces and big flowers in the ground, the color paste should use a paste with better leveling properties, which is conducive to the evenness of the fabric, and the pattern is smooth and full.

4. There are regular, varying sizes of color paste dots on the fabric at the suction point, scattered within a certain range around the pattern, and the conditions remain unchanged. The shape and distance are also basically unchanged.

Measures: Adjust the rise speed of the screen properly to require buffer space when the screen and the fabric are separated, and prevent splashing when the color paste and the screen are separated. The choice of paste should pay attention to reduce the color paste viscosity to ensure the printing effect.

5, pattern photocopying (two-pattern printing) The printed fabric on the pattern of the warp, weft and edge parts of the irrelevant color photocopy, so that the pattern deformation.

Measure: When stretching the net, the net tension should be tightened according to the tension required by the stretch netting process to prevent the netting plate from slacking when the screen is stretched and scraped back and forth with the scraper to ensure the stability of the screen plate and correct installation. Adjust rubber blanket, scraper and squeegee pressure.