Shin-Etsu Chemical Has Developed an Epoch-making Type of Molding Silicone Rubber That Does Not Require Post Cure

28 September 2020

In addition to its already being marketed liquid silicone rubber form, Shin-Etsu Chemical Co., Ltd. (Head Office: Tokyo, President, Yasuhiko Saitoh) has now developed a molding silicone rubber that also does not require post cure in its millable form.

Shin-Etsu is the first in the industry to have developed a millable (high consistency) type* of silicone rubber that does not require a post cure. Shin-Etsu succeeded in developing this breakthrough product by making use of the unique technology that Shin-Etsu Chemical has cultivated over a long period of years.

In the existing molding method for millable-type silicone rubber, after the initial press cure of the silicone molding is performed, a post cure is carried out in order to drive off the residues that are left within the molded product as a result of the vulcanization agent used in rubber molding as well as the low-molecular siloxane.

Compared to the existing product, the new silicone rubber molding product that Shin-Etsu has developed greatly reduces the amount of low-molecular siloxane content, and by employing an addition-reaction cure system that does not create by-products at the time of a press cure, the process of post cure becomes unnecessary. Because of this, our new product will contribute to molding-makers’ productivity improvements and energy saving, and at the same time, we are expecting that this new product will respond to such customer requests as preventing the adhesion of foreign substances to the molded products.

Furthermore, this new product is suitable for various molding methods such as extrusion molding, transfer molding, calender molding, press molding and injection molding.

With regard to its liquid-type silicone rubber, already ahead of others in the industry, Shin-Etsu Chemical is marketing its LIMS (Liquid Injection Molding System) materials that do not require post cure, and LIMS is being widely used in various fields, mainly for applications in automobile parts.

In September 2017 Shin-Etsu Chemical opened a silicone rubber molding technical center. This Shin-Etsu Molding Technical Laboratory is located in Higashimatsuyama City, Saitama Prefecture, Japan. At this Laboratory a millable injection-molding machine is installed, and we will be carrying out demonstrations there of molding using this new product. Going forward, at this Laboratory we will strive to meet the current and also future requests that are received from our customers by enhancing the technical services we will be able to offer to them.

Silicone rubber combines many superior characteristics such as excellent heat resistance, cold resistance, weatherability and stable electrical insulation properties, all of which are not found in ordinary organic rubber. For this reason, it is used in a wide range of applications such as in automobiles, electric-electronics equipment, OA equipment, home appliances and products for daily use.

Taking advantage of Shin-Etsu Chemical's superior product quality and technological strengths as well as our system for detailed response to our customers' requests, going forward Shin-Etsu will continue to strive to meet the needs of the diversifying market.

* millable type: It involves the use of a mixer, called a “roll mill,” and it is a general term for rubber materials that are being mixed.

For inquires about this matter, please contact:
Shin-Etsu Chemical Co., Ltd.
Public Relations Dept.
Tetsuya Koishikawa
Tel: 03-3246-5091, or from outside Japan: 81-3-3246-5091
Fax: 03-3246-5096, or from outside Japan: 81-3-3246-5096
e-mail: [email protected]