Common Issues in PCB Screen Printing Process

• Hole plugging
• Contamination of the reverse side of the printed board by printing material
• Poor adhesion
• Sticking to the net
• Pinhole pitting
• Zigzag printed wires
• Silk screen pattern appearing on the screen printing pattern
• Spots
• Poor overprinting
• Bleeding and spreading of ink
• Uneven color of screen printing

Quality screen printing on PCBs is crucial for the overall performance of electronic devices. To avoid these common issues, it is essential to manage and control the screen printing process effectively. Quality control of printing materials is also key to successful PCB screen printing.

Key Steps to Prevent Screen Printing Issues:

• Enhance management and control of the screen printing process
• Implement strict quality control of printing materials
• Match the screen mesh number with the printing material to prevent hole plugging
• Use appropriate printing material thinner and adjust viscosity to prevent drying and contamination
• Select printing materials that match the substrate for good adhesion
• Avoid sticky net by considering pressure, temperature, and material characteristics

Testing various physical and chemical properties of screen printed products is essential to ensure high-quality PCBs. Factors like corrosion resistance, bending resistance, solvent resistance, and bonding strength directly impact the performance of printed boards. By following these guidelines, conducting pre-test verifications, and collaborating with manufacturers, the occurrence of poor screen printing can be significantly reduced.