The pursuit of high quality screen printing, as screen printing workers, should first have the right quality concept. Second, there should be good work habits, such as the working environment should be kept clean, all appliances should be better maintained. If there is no vacuum cleaner, do not use a brush when cleaning the work environment to avoid flying dust. Cleaning of the floor, cleaning of tables and utensils requires the use of a damp cloth. Clean working conditions can improve the quality of work, improve the working environment, and help achieve high-quality printing.

Film

Before we start printing, we need positive negatives. What are the requirements for a good negative?

* The film base and polyester film of the film should be highly transparent.

* The film side should be on the front side of the film. We often find that some users use the film side is the negative side of the film, used for offset printing positive film, the use of this negative film printing quality will not be guaranteed. Because the silk screen printing plate requires the image of the film side of the film should be in close contact with the photosensitive layer of the film.

* Density (density = darkness) needs to be greater than D3. Offset printing uses less than D3 positive film, so the densitometer should be used to measure the density of the positive film.

* The density of images and texts on the negatives needs higher values. Hand carved masks should not be used as screen printing plates. The film should be made of a high hardness photographic film.

* Use a cleaner or dust-removal roller to clean the negatives before using them.

Wire mesh

The silk screen printing screen is not an ordinary fabric, but a high-strength material with extremely small tolerances. For example, we may all know that in a screen of 120 mesh/cm, there are 24,000 meters of wire per square meter, or 14400 holes per square centimeter, but in fact there is much more to this knowledge about screens.

SEFAR PET1000 mesh has:

1. High tension

2. Low tension loss

3. High tension stability

4. Good wear resistance

5. Low water absorption

6. Good resistance to etch

At the same time, the weaving structure of the screen is also very important for screen printers. You can find the technical specifications you need in the technical documentation. What is the benefit of knowing all these data?

Let us look at the relevant data:

1. Wire diameter: It is the index that determines the final imaging capability.

2. Mesh/CM: The strength and possible tension of the screen can be determined because the effective cross-section and wire diameter of the screen per cm determine the relative stability of the screen. Both of these factors also determine all other parameters. Such as the thickness of the screen, the size of the opening of the screen, the open area ratio of the screen.

3. The thickness of the screen and the area of ​​the opening determine the amount of ink, and theoretical ink penetration volume.

Frame

We all know very well that only a solid frame can control the entire printing process. For example, the magnitude of tension loss and the degree of tension stability.

Stretch net

As explained before. 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 it is regrettable that some stretching machines are covered with a layer of dry adhesive mesh, rubber pads are harder than stones and cannot be closed horizontally.

Obviously, it is impossible for a device like this to stretch out a good screen, and there is still the danger of damaging the screen. Therefore, we should scrape off the glue on the bulge and stick it with peelable tape to protect it. It is recommended to check once a month. It is possible to draw a line on the screen with a copper pen in front of all fixtures that grip the wire mesh. After a moderate tension stretch, if this line is still parallel to the fixture, everything is normal. If not, the fixture needs to be carried out. Adjustment, overhaul.

The stretch net can be stretched according to the tension required by its own production, but it should not exceed the technical parameters promoted 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 breaking the screen with high tension. The size of the pocket should be based on the size of the stretched frame and the required tension. 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.