List Item

Outer
layer rubber

Inner
layer rubber

Test method

Before aging

Tensile strength

Over 18 MPa

Over 10 MPa

ISO 37:1994

Elongation

Over 400%

Over 400%

ISO 37:1994

Hardness

Under 7 0? ?

Under 6 0? ?

ISO 7619:1997

After aging
(Air oven aging
70 ? ? ? à 1 ? ? , 96 h)

Tensile strength

Over 80% of the value before aging

ISO 37:1994

Elongation

Over 80% of the value before aging

ISO 37:1994

Hardness

Not to exceed the original property by more than 8

ISO 7619:1997

Tear

Over 400 N/m

--

ISO 34-1:1994

Compression set

Under 30%
(70 ? ? ? à 1 ? ? , 22 h)

--

ISO 851:1991

Static ozone aging test

No cracks

--

ISO 1431
-1:1989