Understanding of silk screen signs

1.  After the net is stretched car nameplate, why should the screen be pre-processed before the screen is made? What is included in the network pre-processing? A: The pre-treatment of the net is divided into roughening and degreasing. A. For polyester (PET)

The weak polar material is roughened to increase the porous and unsmooth surface on its surface.

The treated PET net can increase the bonding area with photosensitive materials, thus improving the adhesion of photosensitive materials on the net. B.

Degreasing the screen on the screen plate is to remove oil stains, improve the affinity between the photosensitive material and the screen and the printing resistance times of the screen plate, and reduce the pinholes on the photosensitive layer during the making process of the screen plate.

2.  How to make the average unevenness of the surface of the photosensitive layer (PZ value)Reduce? Answer: 1)The PZ value and size are related to the plate making method. Simple plate making method <Capillary direct plate making method <Photosensitive glue plate making method. 2)

The PZ value of plate making method with photosensitive adhesive should be controlled car nameplate, from the following aspects: a.

After the glue is dried, the screen plate is placed flat in the drying oven with the printing surface facing down. B.

The last glue scraping should be on the printing surface, and the screen printing surface should face down when drying. c.

The number of times of scraping photosensitive adhesive on the printing surface increases, which is beneficial to reduce PZ value.

3.  Why must the screen plate be thoroughly dried after being coated with photosensitive glue?

Answer: If there is a slight moisture in the photosensitive adhesive layer, the moisture will refract light during exposure, thus affecting the crosslinking degree of the photosensitive adhesive.

In addition, if the photosensitive glue is not completely dried, cross-linking will also be hindered, resulting in pinholes, degumming, decreased adhesion between the adhesive layer and the silk screen, reduced printing resistance and other defects during development after the screen is exposed.  Therefore, the degree of dryness of the photosensitive layer before exposure is crucial. 4.  How to choose the exposure time of the screen version?

A: Please use the ketutai special exposure slide rule to test.

This slide rule is very simple to use.  You can get five exposure parameters with only one exposure.  The correct exposure parameters must be in it.

5.  What are the consequences of insufficient exposure and overexposure of the screen? Answer: 1)

Underexposure: A.  Pinholes are easy to appear when the photosensitive adhesive layer is thinned too much.

B, pattern or wire edge is easy to produce sawtooth. C, the number of printing resistance of the screen version decreased.

D, it is difficult to recycle the screen plate, and pattern shadows are easy to appear on the screen that has been removed from the film. 2)Overexposed: A.

The pattern will be distorted, the thin lines will be thinner, the low-key dots will be enlarged, and the high-gloss dots will be reduced. B.

It is difficult to flush, and residual glue appears in the leaking part, thus making the ink not mesh. C. The template becomes brittle.

Therefore, the exposure slide rule must be used to determine the accurate exposure time before plate making, so car nameplate, as to produce screen plates with different requirements.

6.  What quality problems will occur when the pre-treated screen and the glued screen are dried in the same oven? How to solve it?

Answer: (1) the water content of the pre-treated screen plate is very high, and a large amount of water will volatilize when drying, thus reducing the drying degree and prolonging the drying time of the screen plate coated with photosensitive glue.

(2) the secondary water absorption of the photosensitive adhesive will make the photosensitive adhesive layer not dry, which makes it difficult to ensure exposure (Print)

The accuracy of the parameters makes the quality of the screen fluctuate greatly.

(3) The solution is to dry separately. Related labels: refrigerator magnets