Silicone rubber keypads have become an increasingly popular switching solution for electronic devices. Also known as an elastomeric keypad, they are characterized by the use of silicone rubber webbing material. Even if you’ve seen or used a silicone rubber keypad, though, you might be wondering how they are made. While silicone rubber keypads can be manufactured using various methods, most of them follow a similar manufacturing process. To learn more about silicone rubber keypads and how they are made, keep reading.
What Makes Silicone Rubber Keypads Unique
Before revealing how they are made, it’s important to know what makes silicone rubber keypads unique. After all, their primary purpose is to offer a switching solution by controlling a circuit — and there are other keypads that serve this same purpose.
Silicone rubber keypads are unique because of their construction. While most other keypads are constructed of hard plastic, silicone rubber keypads live up to their namesake by featuring silicone rubber in their construction. They may still contain other materials in their construction, but they use silicone rubber for their webbing material.
All switches consist of two conductive contacts that are separated by air. In silicone rubber keypads, the conductive contacts are constructed with silicone rubber webbing. The webbing is designed to deform when pressed so that the two conductive contacts touch each other. Releasing your finger from the switch’s button, on the other hand, causes the silicone rubber webbing to revert back to its original state, thereby breaking the circuit.
The Manufacturing Process for Silicone Rubber Keypads
Most silicone rubber keypads are manufactured using a molding process. Molding, of course, involves filling a die with liquid material so that it creates a new object in the same shape. The silicone rubber material is used to fill the die (or dies) to form the switch’s webbing.
Some silicone rubber keypads are manufactured using compression molding, whereas others are manufactured using injection molding. Compression molding is characterized by the use of compression. It forces the silicone rubber material into the die via compression. Injection molding, on the other hand, uses a machine to inject heated silicone rubber into the die. Both compression and injection molding are frequently used to manufacture silicone rubber keypads.
Molding processes such as these support a variety of colors, textures and backlighting solutions. Furthermore, silicone rubber keypads can be easily molded with conductive pills as well as assembled with either polyester or metal dome arrays.