SARCON® YR-a is a Highly Thermal Conductive and Non-Flammable Silicone Rubber.

・ SARCON® YR-a is a highly conformable/thermally conductive silicone material.
・ 2.2watt/m-K and 3.9watt/m-K (No electricity conductive) in a veratile sheet make reliable and complete physical contact.
・ 1) Gives the lower thermal resistance.
・ 2) Has a flame retardancy of UL specification 94V-0 equivalent.

Typical Product Properties
ItemUnit20Y-a30Y-a45Y-aTest Method
Thermal ConductiviyW/m-K2.2ASTMD5470
Thermal Resistance℃・inch2/Watt0.110.220.26Fujipoly Test Method #1
Flame Retardancy-94 V-0 (Recognized)UL 94 Standard

Note.) #1: FTM P-3010 which gives ASTM D5470 equivalent value.

Typical Material Properties;
ItemUnitYR-aTest Method




Specific Gravity-2.6

JIS K 6220 / ASTM D792

HardnessType A84

JIS K 6249 (ASTM D2240)

Tensile StrengthMPa4

JIS K 6251 (#2 Die) / ASTM D412


JIS K 6251 (#2 Die) / ASTM D412

Tear Resistance


JIS K 6252 (Angle) / ASTM D624

Volume Resistivity

MΩ・cm×106JIS K 6249 / ASTM D257
Withstand Voltage (0.2mmT)KV/minute3JIS K 6249 (AC 60Hz) / ASTM D149
Withstand Voltage (0.3mmT)KV/minute9

Dielectric constant

50Hz4.8JIS K 6911 / ASTM D150 equivalent

Dielectric Dissipation Factor

50Hz0.019JIS K 6911 / ASTM D150 equivalent
Maximum Use Temperature -60 to +180 
Statement of Lieu of Warranty

• Properties of the products may be revised due to some changes for improving performance.
• Properties values in this document are not specification or guaranteed.
• This product is made of silicone, and silicone oil may exude from the product.
• This product is made of silicone, and low molecular siloxane may vaporize depending on operating conditions.
• The product is designed, developed, and manufactured for general industrial use only. Never use for medical, surgical, and/or relating purposes. Never use for the purpose of implantation and/or other purposes by which apart of or whole product remains in human body.
• Before using, a safety must be evaluated and verified by the purchaser.
• Contents described in the document do not guarantee the performances and qualities required for the purchaser’s specific purposes. The purchaser is responsible for pre-testing the product under the purchaser’s specific.
• Statements concerning possible or suggested uses made herein may not be relied upon, or be constructed, as a guaranty of no patent infringement.

Handling Notes

• It is recommended to use the material in up to 30% of compression ratio. Using the material beyond the recommended compression rate may result in excessive silicone oil exudation.
• It is recommended to compress the material with the equal ratio on the whole surface. Partial excessive stress may also result in excessive silicone oil exudation.

Fujipoly: Thermal Interface Materials

YR-a Thermal Interface Materials

ISO 9001:2015