7 Tips For Screen Printing
Screen printing is a common printing method. Screen printing is mainly divided into dry and wet. The so-called dry printing is to place the screen on the printing solvent, and then spray the ink onto screen printing machine. After drying, the printing operation can be carried out. This printing method is more suitable for making large three-dimensional packaging products. Among them, dry printing technology is the most widely used and has the largest output.
1. remove impurities from the screen before printing
Before printing, the impurities in the screen should be removed to avoid affecting the screen printing effect. Impurities in the screen will affect the adhesion of the ink to the screen printing ink. And affect the printing ink absorption ability in the screen surface.
2. Use ink with proper concentration
Ink is mainly divided into two kinds, one is low-end ink, the other is high-end ink. Low end inks need to add some solvents, or some additives, such as calcium carbonate, etc. It will make ink bright and high saturation, while high-end inks need to add some solvents to improve color intensity and scratch resistance. In addition, when low-end ink is mixed with a variety of solvents, it is necessary to add some additives to the ink to improve the ink concentration, rather than directly adding a large number of dyes to improve the color strength of the ink. Some solvents can be directly added to the ink to improve the ink concentration. In this way, we should pay attention to maintaining the ink balance, otherwise the reaction between ink and pigment will lead to uneven color and fast color change.
3. Avoid using substances containing acid and alkali
In screen printing, if substances that are against to the volatilization of ink and solvent are used, the ink will be absorbed and the printing quality will decline. If the ink or solvent containing strong acid and alkali is used, it will cause damage to screen printing. To avoid this problem, you can add a small amount of water to the ink or use a clean cloth or cloth to cover the ink to reduce ink volatilization. If screen printing ink with alkaline composition is used, it should be cleaned and dried in time and placed in a ventilated place. The use of acid and alkali substances is a big damage to ink. When the ink contacts with this solvent, it will damage the ink, resulting in a decline in printing quality.
4. Printing with drying equipment
Drying equipment has a great impact on the printing effect. In a humid environment, screen printing is prone to ink layer adhesion, or even poor drying. Therefore, the drying equipment must have sufficient moisture resistance to ensure the printing effect. For dry printing machine, it also has the advantages of high drying efficiency and full color of printed matter. The drying equipment must pay attention to the control of temperature, pressure and time.
5. Maintain the printing press
When using screen printing equipment, the machine should be checked regularly. Especially when printing, the machine should be protected from impact and wear, and should be checked frequently by hand. If burrs are found on the surface of the machine, it needs to be cleaned with plenty of soapy water and dried.
6. Maintain printer
After a period of use, the printing machine must be cleaned and dried in time. When the printing machine nozzle is dry, be sure to wipe it with a clean rag, and then rinse it with clean water. In the process of cleaning, high-pressure water gun can be used for cleaning, and do not wash directly with soap or detergent. Otherwise, the precision screen will be damaged. In the cleaning process, once the leakage net and residual water droplets are found, they must be replaced in time.
7. Control the screen tension
The size of screen tension is related to the viscosity of ink and the structure of screen material. When the screen tension is too small, the ink is easy to diffuse to the screen, causing the loss of printing dots. When the screen tension is too large, the ink is not easy to diffuse to the screen, causing the loss of printing dots. Therefore, the appropriate screen tension should be selected according to the characteristics of different substrates. Generally, when the viscosity of the ink is relatively low, a general printing press can be used.
Leave A Comment
Your email address will not be published. Required fields are marked *