PCB Silkscreen

Silkscreen is the nomenclature or pieces of information printed on PCBs, most commonly in white ink. It comprises some letters and numbers, which are readable to the normal human eye. These indicate the names of various mounted components, soldered parts, test points, part numbers, date codes, manufacturer’s logo, warnings, and so on. Silkscreening is normally performed using formulated inks. They are usually non-conductive epoxy inks. Twisted Traces is an old and established player in PCB manufacturing and has been practicing this artwork to help layer and component identification in circuit boards. We do this at our state-of-the-art PCB manufacturing facility. Usually we use standard font style and size; however, it can be customized as per your requirement.

Our Approach to PCB Silkscreening

As a silkscreen circuit board manufacturer with vast experience, we, at Twisted Traces only use formulated colors such as white and black for silkscreening. We use inkjet printers to image the legends directly from the digital data of the board. The printer sprays small ink droplets onto the panel to create an image. For creating a legend on the other side, the ink tack is dried, and the printing is repeated. No additional setup is required for inkjet printing. This process takes less than 10 minutes in a conveyorized oven. We employ any of these methods for silkscreening on a printed circuit board:

• Manual Screen Printing: This method is applied when the line widths are greater than 7 mil, with the registration tolerance of 5 mil. In this method, a stencil of the text is used through which the ink is pushed onto the laminate. The ink is cured by baking the PCB in an oven. This method is easy to implement; however, it is applied where precision is not a critical parameter.
• Liquid Photo Imaging (LPI): This method is utilized when the line width is greater than 4 mil. This process has some similarities with the one used for the application of soldered mask. In this method, a liquid epoxy is coated onto the laminate and dried in UV light after which the board is cured. LPI enables better precision compared to manual screen printing.
• Direct Legend Printing (DLP): This method is more appropriate for complex printed circuit boards. It is relatively expensive but offers utmost precision and accuracy. In this method, Acrylic ink is applied on a PCB with the help of an inkjet printer. Simultaneously, the ink is cured with UV light. However, this method is not suitable for boards with silver laminates.

Being an industry-leading silkscreen circuit board manufacturer, we have mastered manual silkscreening, over the years. Our experts will help you choose and appropriate silkscreening method.

Importance of Silkscreening for a PCB Manufacturer and Its Benefits

Aside from identifying components and layers, silkscreening is important and beneficial to the manufacturer in many ways. Here we have also mentioned some benefits of working with us: