Patent ID: 8735523

Claim:
Bulk oriented polymer crystalline materials comprising crystals of the polymer and satisfying the following requirements (I) and (II): (I) the bulk oriented polymer crystalline materials have a crystallinity of 80% or greater; and (II) the crystals are 100 nm or less in size, wherein the crystallinity X c is calculated using following Equation (1) X c =1−( I a /I a 0 ) Equation (1) where I a is an integrated scattering intensity of amorphous contained in a sample and I a 0 is an integrated scattering intensity of a 100% amorphous sample, the 100% amorphous sample having a crystallinity of 0%, and wherein said bulk oriented polymer crystalline materials are obtained by a production method including the steps of (i) putting a polymer melt in an oriented melt state by elongating the polymer melt at a strain rate of 400 s 1 or greater which is greater than a critical elongation strain rate of 150 s −1 , and (ii) crystallizing the polymer melt while keeping the polymer melt in the oriented melt state.