Mechanical Rubber

Quality and Competence

Asahi Rubber has been a trusted supplier of a variety of mechanical rubber parts across industries ranging from automotive to sporting goods to consumer electronics and many more for decades from our Japan and PRC manufacturing facilities.

We have experience in silicone, NBR, H-NBR, EPDM, PVC, fluorosilicone, other fluoropolymers, and more, and can design tooling for and produce with molding methods including compression, injection, transfer, and extrusion.

Long Automotive Track Record

>30 years of engineering/delivery for the automotive market

IATF 16949 Certified

Development Support

Capable of proposing set ideas as well as discrete rubber part designs

Equipped for Thorough Evaluation and Controls

Flexible facility set-up to support unique parts is possible

Automotive requirements evaluated consistently in-house

Exacting siloxane controls

Foreign Contaminant Control

Inspection→shipment processes housed in dedicated booth

OEM Customers

Tier 1 Customers

A Glimpse at Our Production Processes

Incoming Inspection

Raw material confirmed on-spec


Polymer and additives kneaded together


Rolled material cut into precise preforms ready for molding


50~350t press

Control time, temp, pressure

Std. compression or millable injection


Hydraulic or manual press + cutting jig

Remove burrs and flash

Quality and Compliance Control

A full suite of test equipment and fully ISO 9001 / IATF 16949 / ISO 14001 certified facilities back up our day-in day-out commitment to dependability.

Test Equipment

Climatic Test Chamber

Controlled environment -65 to +150°C, humidity adjustable

Gas Chromatograph

Residual siloxane levels evaluated

2D & 3D Measurement

Precise dimensional control

X-Ray Fluorescence Analyzer

RoHS 6 compliance check


Machine Vision



Packaging – Inner

Packaging – Outer


A particularly demanding application of rubber engineering, switchpads require delicate control of material and form to meet stringent requirements over years of operation.

Contact types

Asahi Rubber offers an array of contact options to meet diverse needs. All are robust chip type contacts.

Cross-SectionResistanceDiameter (mm)CharacteristicsUse Cases (Automotive)
Gold, Flexible≤1Ω⌀3・Flexible for sure contact
・Au & Ni corrosion resistance
Power Window SW

Steering SW

Parking SW

Engine Start/Stop SW
Gold≤1Ω⌀3・Basic low Ω contact
Nickel≤1Ω⌀3・Ni high corrosion resistance
・Uneven surface for reliable contact
・Cheaper option than gold
Carbon, Low Resistance≤20Ω⌀3・Silicone rubber matrix
Carbon, Standard≤200Ω⌀2.5~3.5・Silicone rubber matrix
・Cheapest option
Audio SW
*all types automotive grade

Polymer Grade

Elastomeric switch pad silicone rubber (VMQ) is supplied in multiple grades, selected based on desired F-S and durability characteristics.

Low Load/Low Snap

Standard Grade

High Load/High Snap

High Grade

Silicone rubber has particularly useful characteristics of strong heat and cold resistance, flame retardance, and weatherability in all grades.

Force-Stroke (FS) Curve

Adjusting multiple parameters in concert dials in just the right button feel.

F1 (N)F1/F2 (%)S2 (mm)
Examples of the range of our past project specifications

S1 is the depth, F1 the force at which the switch activates and the silicone membrane inverts.

S2, F2 is the bottom-out point–from here further button press encounters resistance from the material itself compressing.

Additionally the keytop can be made hollow to adjust the resistance transferred to the user post-activation, beyond S2/F2.

F-S Track Record by Stroke Depth

Switch feel guaranteed

Switchpad-Specific Quality Control

Automated Load Measurement

F-S characteristics assured

Automated Stroke Measurement

Durability test for long-term performance

Adjustable for load and cycle count