ニードルパンチ式不織布の研究

第2報　パンチ布の引張り特性

抄録

When the web is punched by the needles with barbs, it is bored with holes corresponding to fineness of needles. The web is lifted by the lifting needles and pulled by the delivery roller. So the web is enlarged by puching. The thickness of fabric decreases on account of the enlarged area and condensation.
Assuming that the specific density of fabric is ρ and the density of fibers is ρ_f, the relativedensity of the fabric, S is ρ/ρ_f.
Anisotropy of tensile properties is due to the property of random web, if punching is uniform. If the entangle of fiber increases and the fiber does not move with increasing punches, the fibers will be broken.
As the entangle is increased and at the same time fibers broken, the maximum breaking strength. will be observed within a certain range. The number of punches yielding the maximum strength increases with fineness of fibers. The punched fabric is mainly broken by the drawing out of fibers.