Chemical-resistant fluoro elastomer

TOMBO™ No. 2670-FB

Rubber O-ring Fluoroelastomer FB

Fluoroelastomer FB is a ternary fluoroelastomer with improved chemical resistance due to Nichias’ proprietary compounding technologies. It has excellent resistance against high-temperature acids and steam for which a general-use fluoroelastomer cannot be used. There is very little metal elution and it has excellent purity. A high-performance fluoroelastomer that is excellent value for money.

Product Category

Elastomer ProductsPTFE Covered Elastomer / General Purpose Elastomer


Chemistry & PetrochemistryOil Refining & PetrochemistryChemistryElectronicsSemiconductors & Flat Panel Displays (FPD)Electronic Components


Heat resistance guide: 200°C
Standard hardness (Duro A): 70
General-use fluoro elastomer can be used for quickly degrading, high-temperature inorganic acids, steam, and sodium hydroxide.
There is almost no elution of the metal from chemical solutions.


Cleaning equipment, wet etching equipment, filters, etc.

Eluted metal measurement results

As fluoroelastomer FB is not a compound that contains metal, it experiences a lot less metal ion elution than that of fluoroelastomer FA.

Test conditions

After cleaning with 5% hydrofluoric acid, it is cleaned with ultrapure water.
Test specimen: O-ring P16 (thickness Φ2.4 × inside diameter Φ15.8)
Chemical solution: 50% hydrofluoric acid 300 g
Temperature × time: 24°C × 72 hours (3 days)
Analysis method


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