Microcellular polyurethane vibration isolator
AssigneeNisshin Spinning Co., Ltd.
InventorsTatsuya Hongu, Toshio Suzuki, Yoshihiko Ogawa
Life of this patent
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Abstract
A vibration isolator consisting essentially of a microcellular polyurethane elastomer having a bulk density of 0.3-0.9 g/cm.sup.3, said polyurethane elastomer obtained by reacting in the presence of water as the blowing agent (a) an organic polyisocyanate, (b) a polyether polyol having an average number of functional groups of 2.5-3.5 and a number average molecular weight of 4500-8500, and (c) a chain extender, in such a ratio that the NCO index is 90-110 and the concentration of the chain extender, based on the total weight of the three components (a), (b) and (c), is (0.4-2.0).times.10.sup.-3 equivalent/gram.
Claims12
A vibration isolator consisting essentially of a microcellular polyurethane elastomer having a bulk density of 0.3-0.9 g/cm.sup.3, a tensile strength of at least 5 kg/cm.sup.2, a spring constant of at least 0.1 ton/cm, a permanent compression set of 25% at the most, and a fatigue strength of 2.0 mm at the most, said polyurethane elastomer obtained by reacting in the presence of water as the blowing agent
- (a) an organic polyisocyanate,
- (b) a polyether polyol having an average number of functional groups of 2.5-3.5 and a number molecular weight of 4500-8500, and which is obtained by addition polymerizing ethylene oxide and propylene oxide with a lower aliphatic polyhydric alcohol of 2-6 carbon atoms or with a low molecular weight active hydrogen-containing compound containing at least two active hydrogen atoms, and
- (c) a chain extender, in such a ratio that the NCO index is 90-110 and the concentration of the chain extender, based on the total weight of the three components (a), (b), and (c) is 0.4.times.10.sup.-3 to 2.0.times.10.sup.-3 equivalent/gram.
Dependencies are inferred from the claim text.