The Many Advantages of Liquid Silicone Rubber Molding

Posted by Ainsley Aiken on December 29th, 2018

The injection molding of silicone rubber is a complex process. But, the most important is what the advantages of these multistep processes are? The answer is –this loop system avoids any contamination of liquid silicone. If not followed, the contamination can occur anywhere. There are still some advantages. Let’s consider them in detail.

Decreased Time of Processing Cycle

All the keypads and components have a cycle time of approximately 30 seconds and 2 minutes. This increases the time of production in comparison to compression molding.

Fleshless Tooling

Liquid Silicone molds inject the silicone after the mold has closed. It is done with the help of flash rings. The tooling leaves little to no flash on the parts, with the use of flash rings, vent tracks, and a well-designed runner system. This decreases the amount of time required for de-flashing the trim part.

No Need of Pre-forms

A pre-form is a basic shape of the end product which is put in the processing cavities during compression molding. These pre-forms should be a surplus of material which ensures a total cavity fill. The surplus material is pressed between the two molds causing flash around all of the cavities. But, the silicone Rubber Molding requires no pre-forms. 

Production of Insert Molded Components

Injection molding of silicone rubber ensures the placement of pre-molded clear silicone inserts in the tool. Then, these silicone inserts become “over-molded” with the preferred color. This creates a seamless bond between the insert and over-mold. This gives accessibility for the blockage of light between keys. It also eliminates the requirement for the customer to design custom light blocking components within the PCB. Hence, the clear inserts can also be used for display windows to show mechanism or digital screens behind the silicone keypad.

Minimizes Waste

By using the injection rubber molding minimum waste of material occurs. The material is only wasted within the spree and runner system which leads to the component or keypad. This can be removed with the help of a cold runner system. This keeps the silicone cool within the runner and spree. Where the material waste has huge effects on the cost, these systems are typically used on large scale.

Hope this basic information about injection molding will help you. If you want to know more about molding, let us know. We will bring more posts to make your products better.