Patent ID: 8217090

Claim:
An elastomer porous material, wherein: when cells in a first observation region of a first cross section are observed at a certain magnification, cells having a shape factor SF 2 of 130 or less account for 80% or more of all cells in the first observation region, wherein SF 2 indicates remoteness from complete roundness and is represented by formula F1: SF ⁢ ⁢ 2 = P 2 4 ⁢ π ⁢ ⁢ A × 100 , wherein A represents an area of each cell, and P represents a perimeter length thereof, and when cells in a second observation region of a second cross section orthogonal to the first cross section are observed at said certain magnification, cells having the shape factor SF 2 of 130 or less account for 80% or more of all cells in the second observation region.