When designing your Printed Circuit Boards that require a keypad to be backlit, it is important to know all of the methods in which a silicone rubber keypad can be molded. There have been numerous improvements to the once “standard” method of mold clear, coat black and laser. Knowing these methods can save countless hours in design time and help provide an overall better quality product.

Insert molding has become the new standard here at SiTech, as this method provides the capability to light individual keys, without light bleeding from one key to the next. Below are a few examples various types of inserts we use in our silicone rubber products:

• Light pipes for LED indicators
• Clear windows for displays
• Keys for backlit silicone keypads

This method does require a light source for each key, as an opaque material is molded around each of the inserts, creating a molded light block.  This method has proven extremely useful in specific scenarios where a single key requires multiple Indicators / and or colors for specific areas of the key. Multiple inserts can be molded into each individual key to provide the molded light block between the translucent inserts. This method eliminates the need for secondary light blocks to be molded and attached to the PCB’s.

Taking inserts into consideration when designing your PCB can save a lot of design time or re-design time. Often utilizing the old mold clear and coat black method, companies would struggle with determining custom methods to block light. Most of the time, this hassle could be eliminated completely if the company was only aware of pre-existing alternative molding methods. We encourage this method whenever possible, but there are cases where the PCB has already been designed, and built, and it would be too costly to incorporate these methods into their existing design.

SiTECH has the capability and experience to incorporate multiple inserts within a single individual key. Some of our keypad assemblies have upwards of 40+ individual inserts. So if you have any questions or would like to learn more about the different capabilities of insert molding or if you need any assistance with your silicone rubber products please contact Si-Tech today at 757-887-8488 or CS@SiTech-Corp.com. Our silicone keypads and custom components are created with state-of-the-art technology using only liquid injection molding at our headquarters located in Newport News, Virginia. We are fully ITAR certified and are proud to serve the needs of our customers with products made with the craftsmanship and quality of American professionals.