How to solve the problem of glue blocking the mesh when screen printing hot melt glue?

How to solve the problem of glue blocking the mesh when screen printing hot melt glue?
When screen printing hot melt glue, glue blocking the mesh will affect the printing effect and efficiency. Here are some ways to solve this problem:
Choose the appropriate mesh number of the screen: According to the characteristics of the hot melt glue and printing requirements, choose the appropriate mesh number of the screen. If the mesh number is too high and the mesh is too small, the glue is easy to be blocked; if the mesh number is too low, the ideal printing accuracy and effect may not be achieved. Generally speaking, for the printing of hot melt glue, a screen with 100-200 mesh can be selected. The specific mesh number needs to be determined through experiments to ensure that the glue can pass through the mesh smoothly and the printing quality is good.
Dilute the hot melt glue: If the viscosity of the hot melt glue is too high, it is easy to cause the mesh to be blocked. According to the characteristics of the glue, it can be diluted with an appropriate diluent. During the dilution process, the prescribed ratio must be strictly followed to avoid excessive dilution affecting the viscosity and printing effect of the glue. At the same time, the diluted glue should be fully stirred to ensure its stable performance.
Control printing speed and pressure: Too slow printing speed or too high pressure may cause glue to accumulate in the mesh, causing blockage. During the printing process, the printing speed and pressure should be reasonably controlled according to the fluidity of the glue and the characteristics of the screen. Generally speaking, maintaining a moderate printing speed and pressure can make the glue pass through the mesh evenly and reduce the possibility of blockage.
Clean the screen regularly: During the printing process, the screen should be cleaned regularly to remove the residual glue in the mesh in time. You can use a special screen cleaner or solvent and follow the cleaning instructions. When cleaning, be careful not to damage the screen to ensure that the tension and performance of the screen are not affected. After cleaning, the screen should be thoroughly dried before printing.
Use anti-blocking screen agent: Adding an appropriate amount of anti-blocking screen agent to the hot melt glue can effectively reduce the surface tension of the glue, reduce the adhesion and accumulation of glue in the mesh, and thus prevent the mesh from being blocked. When using the anti-blocking screen agent, pay attention to its compatibility with the glue, add it according to the prescribed proportion, and stir it thoroughly.
Improve the printing environment: Keep the printing environment clean and dry, avoid dust, impurities, etc. from entering the glue and screen, and reduce factors that block the mesh. At the same time, control the temperature and humidity of the printing environment to avoid environmental factors affecting the performance and fluidity of the glue.
Choose a suitable scraper: The hardness and angle of the scraper have a certain impact on the printing effect and the blockage of the mesh. Choose a scraper with moderate hardness and appropriate angle to better scrape the glue evenly across the screen and reduce the residue and accumulation of glue in the mesh. Generally speaking, the hardness of the scraper is more suitable between 60-80 degrees, and the angle of the scraper can be adjusted between 45-75 degrees according to actual conditions.