Patent ID: 11926724
Assignee: ZEON CORPORATION
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC C | IPC C

Claim 0:
1. A method for manufacturing a foam rubber, comprising foaming a polymer latex,
wherein the polymer latex used has a solids content of 60.0 wt % or more, has a volume particle size distribution where a volume cumulative particle size d10 is more than 140 nm, and comprises 0.001 to 0.1 part by weight of antifoaming agent relative to 100 parts by weight of polymer in the polymer latex,
the volume particle size distribution of the polymer latex has two or more maxima,
the polymer latex has a ratio of a height h2nd to a height h1st (h2nd/h1st) of 1.8 or more, where the height h1st represents the height of the peak closest to the smaller diameter end of the volume particle size distribution, and the height h2nd represents the height of the second peak counted from the smaller diameter end of the particle size distribution,
the particle size d1st of the peak closest to the smaller diameter end of the volume particle size distribution is 150 to 500 nm,
the particle size d2nd of the second peak counted from the smaller diameter end is 950 to 3000 nm,
a polymer forming the polymer latex is a nitrile group containing conjugated diene copolymer containing acrylonitrile, butadiene and isoprene units, an amount of the acrylonitrile unit is 20 to 60 wt % and a total amount of the butadiene and isoprene units is 40 to 80 wt %, and
the antifoaming agent is at least one selected from the group consisting of a mineral oil antifoaming agent and a silicone antifoaming agent.