The separator production method in accordance with an embodiment of the present invention includes a coated article taking up step of taking up a separator original sheet by winding the separator original sheet on an outer peripheral surface of a core while oscillating the core in the rotation axis direction; a coated article winding off step of winding off the separator original sheet, which has been taken up in the coated article taking up step, from the core; and a transferring step of transferring the separator original sheet, which has been wound off in the coated article winding off step, such that a state of being distorted in a wavelike manner in the transverse direction is maintained.

A bio-based polyester thin film substrate for thermal transfer printing ribbon. The bio-based polyester thermal transfer ribbon substrate film has a radiocarbon content of at least 12 pMC. The film exhibits excellent uniformity, handling, and processability, substantially equivalent to petroleum-based counterparts, while being derived wholly or partly from non-petroleum sources.

A porous polytetrafluoroethylene (PTFE) membrane including a nonwoven web having a microstructure of substantially only microfibrils fused at crossover points, said membrane having a percent balance of orthogonal dimensions that is within 10%.

The present invention provides a transversely uniaxially oriented polymeric shrink film that comprises both an inorganic opacifying agent and an organic polymeric cavitating agent in a cavitated layer thereof.