High-quality screen printing application technology (in)

Stretching the net: As explained by the residence. According to the average effective cross-section of the screen, each different screen has its maximum tension. Only use a well-maintained stretching machine to reach this maximum tension. Sometimes, some stretching machines do make people feel sorry. The jig is covered with a layer of dry adhesive mesh. The rubber mat is harder than the stone and cannot be closed horizontally. Obviously, it is impossible for a device like this to draw out a good screen, and there is also the danger of damaging the screen. Therefore, we should scrape off the adhesive from the fixture and apply it with scraping tape. For protection. It is recommended to check once a month. You can draw a line on the screen with a pencil in front of all clamps that clamp the screen. After a moderate tension stretch, if this line is still parallel to the clamp, everything is OK. If not, you need to adjust the clamp. Maintenance.

The stretch net can be stretched according to the tension required by its own production, but it should not exceed the technical parameters recommended by the wire mesh manufacturer. At the same time, it should be noted that the screens at the four corners of the stretcher need to be pocket-shaped to avoid pulling the screen too high. The size of the pocket should be based on the size of the stretched frame and the tension required. At the same time, the gaps between the clamps in the four corners need to remain at least equal to the width of the cross-section of the frame material, so that the wire mesh stretches to the specified tension without breaking the net.

On each stretched screen plate, the following data should be written on the edge of the frame: number of meshes, wire diameter, initial tension, screen number, stretch date, and the name of the person in charge. Stretch the screen for at least 24 hours before using it, so that we can get a stable, qualified screen.

The best conditions for the online version: everything should strive for perfection. Prints that appear jagged can look ugly, and poor quality screens are prone to cracking during the printing process, and they have to be remade. This wastes time and materials, and can make people feel full of work. Disappointed. So we need to work in accordance with a standard work flow diagram, which may have the following requirements and conditions.

1. Keep the tool clean so that it can be used at any time. The plate making room should be free of dust.

2, check the screen tension. All and multi-color sets of screens need the same tension;

3. Fully degreasing: Use a soft brush and a water source with a certain pressure to clean it.

4, drying at temperatures below 400C.

5, according to the manufacturer's recommended method, 12 minutes in advance with a good photopolymer.

6, using a clean, slightly rounded edge of the sizing device for gluing, gluing area is at least 10% smaller than the inner diameter of the frame.

7, when gluing, we must first start from the printing surface. The number of times of gluing depends on the solid content of the emulsion, the viscosity, the number of screen meshes, and the desired screen thickness.

8. When drying the screen, the brush should be placed with the brush facing downwards (avoiding the sensible glue flowing back to the ink surface).

9, for fine-line printing and halftone printing screen, after each drying need to be painted on the printed surface once or more times feel the light adhesive, until the printing surface of the photosensitive layer until the smooth.

10. Keep the exposure machine's glass vacuum eraser clean. Check the film is correct? Does the film surface fit on the screen? Does blackness meet the requirements and is it placed correctly? Let the exposure machine have enough vacuum chamber.

11. Set the correct exposure time and keep the record. Every three months or when the exposure decreases, the exposure time should be tested and adjusted to correct.

12. Keep the exposed screen away from the light source (daylight, incandescent lamp).

13, development should use the appropriate pressure of water for cleaning and development, in particular, the ink surface should be fully cleaned and can not be washed until the surface is not slippery. Insufficiently exposed photographic plate will show release after cleaning.

14. Use a soft, clean paper, a clean cloth, or a vacuum cleaner to remove excess moisture.

15. Use a suitable patch of material to repair the screen.

16. Write all parameters to the screen: thickness, exposure time, date, and name. Of course, for the production of film with capillary film, the production method will be a little different, but the degreasing, drying temperature, exposure time and cleaning requirements are the same.

Reasons for deviation in printing accuracy:

1. When making multi-color overlay (halftone printing) screens, the screens are dried at different temperatures, thereby causing errors in the printing accuracy.

2. The screen tension is low or overprint (halftone) screen tension is different.

3, using a hair dryer to dry, screen drying uneven.

4. The use of too old, unsturdy, and distorted mesh-plate making results in deviations in the printed image due to poor stability of the frame (these problems can be detected with a negative film).

5, multi-color overlay, the use of inconsistent distance.

6, squeegee deformation.

7, subject to certain factors caused by the size of the substrate.