BASE MATERIAL FOR HONEYCOMB CORE STRUCTURE AND PROCESS FOR PRODUCING THE SAME

摘要

A base material for a honeycomb core structure comprises a paper-like polyester fiber sheet comprising 20% to 80% by weight of drawn polyester staple fibers which preferably have a flat cross-sectional profile having a flatness, which refers to a ratio in length of a major axis to a minor axis of the profile, of from 2.5 to 30.0, 20% to 80% by weight of the sum of undrawn polyester staple fibers and other polyester staple fibers having a lower melting point than that of the undrawn polyester fibers, and having a porosity of 60% or less and a resistance to permeation of air of 100 sec/100 ml or more.