US 2003/0077968 A1 · Transversely stretched nonwoven fabric with high tensile strength stretched seven times wider or more in transverse direction

Abstract

A transversely stretched nonwoven fabric is manufactured by transversely stretching a nonwoven fabric. First, an original web comprising a plurality of un-oriented filaments is heated to a temperature higher than its stretch suitable temperature by 5° C. or more. Next, the heated original web is stretched at a rate of 1.2 to 3 in its transverse direction to stretch the filaments of the original web with almost no molecular orientation involved. Then, the original web stretched transversely at a rate of 1.2 to 3 is heated to the stretch suitable temperature and the original web is further stretched transversely at the stretch suitable temperature. With these steps, a transversely stretched nonwoven fabric in which the original web is stretched transversely at a rate of 7 times or more in total as compared with the state of the stretch thereof is manufactured with a high tensile strength of 132.5 mN/tex (1.5 g/d) in the transverse direction.

Claims20

Dependent claims

A transversely stretched nonwoven fabric comprising:

a plurality of filaments stretched and aligned in a transverse direction and having a fiber diameter of 20 μm or less;
said transversely stretched nonwoven fabric being stretched in said transverse direction at a rate of 7 times or more, and having a tensile strength of 132.5 mN/tex or higher.

A method of manufacturing a transversely stretched nonwoven fabric, comprising the steps of:

stretching an original web comprising un-oriented filaments 1.2 to 3 times wider in a transverse direction of said original web at a temperature higher than its stretch suitable temperature by 5° C. or more;
and
further stretching said original web stretched 1.2 to 3 times wider in said transverse direction at said stretch suitable temperature such that said original web has a tensile strength of 132.5 mN/tex or higher in its transverse direction to stretch said original web 7 times wider or more in said transverse direction in total as compared with the state before the stretch thereof for manufacturing a transversely stretched nonwoven fabric comprising said filaments of said original web aligned transversely.

A transverse stretch apparatus comprising:

first heating means for heating an original web comprising a plurality of un-oriented filaments to a temperature higher than a stretch suitable temperature of said original web by 5° C. or more;
first stretch means for stretching said original web heated by said first heating means 1.2 to 3 times wider in a transverse direction;
second heating means for heating said original web stretched transversely by said first stretch means to said stretch suitable temperature;
and
second stretch means for further stretching transversely said original web heated to said stretch suitable temperature by said second heating means such that said original web is stretched 7 times wider or more in the transverse direction in total as compared with the state before the stretch of said original web by said first stretch means.

2 more elements

Dependencies are inferred from the claim text.

Transversely stretched nonwoven fabric with high tensile strength stretched seven times wider or more in transverse direction

Life of this patent

Transversely stretched nonwoven fabric with high tensile strength stretched seven times wider or more in transverse direction

Life of this patent

Abstract

Claims20