The preparation method of silicone rubber for keys mainly includes the following steps:
Raw material preparation: The main raw material of silicone keys is high temperature vulcanized rubber (silicone rubber). Raw material preparation is the first step of the entire production process, including the mixing of raw rubber, color matching, and weight calculation of raw materials. When mixing raw rubber, various raw materials need to be mixed according to a specific formula to ensure the stable performance of the final product. The color matching link is to mix the required color according to customer needs. The weight calculation of raw materials is also crucial, and accurate measurement can ensure the consistent quality of each batch of silicone keys.
Mold design and manufacturing: The design and manufacturing of molds is one of the core links. According to the 3D drawings or samples provided by the customer, the engineer will design the mold opening drawings and then manufacture the mold. The accuracy of the mold directly affects the dimensional accuracy and appearance quality of the silicone keys. Keys for different purposes have different structures, elastic walls, etc. Experienced manufacturers will give reasonable suggestions based on actual application scenarios.
Vulcanization molding: Vulcanization molding is a key step in the production of silicone keys, also known as hydraulic molding. This step uses high-pressure vulcanization equipment to vulcanize the silicone raw materials at high temperature in the mold to solidify them. The choice of vulcanization temperature and time has an important impact on the performance of the final product. Too high a temperature will cause the silicone keys to become brittle and easy to break; too low a temperature may cause the product to stick to the mold and be difficult to demold. Therefore, the temperature and time need to be strictly controlled during the vulcanization molding process.
Deburring and processing: The silicone keys that are removed from the mold will be accompanied by some useless burrs and hole chips, which need to be cleaned up through the deburring process. It is usually done by hand, and some factories also use punching machines to improve efficiency. After deburring, the silicone keys need further processing, such as silk screen printing. The silk screen printing process is mainly used to print characters or patterns on the surface of the keys to facilitate user operation.
Injection and feel processing: Silicone keys are easy to absorb dust in the air under normal conditions and have a certain degree of viscosity. In order to improve its dustproof performance and feel, a thin layer of feel oil is usually sprayed on the surface of the key. This layer of feel oil can not only prevent dust from adhering, but also improve the touch of the key.
Additional function processing: In order to meet the diverse needs of customers, silicone keys can also add some additional functions during the production process. For example, glue dripping can increase the hardness and wear resistance of the key; laser engraving can engrave translucent characters or patterns on the key to achieve the effect of key luminescence; P+R synthesis can compound silicone keys with other materials (such as plastics) to improve the overall performance of the product.