US 2026/0152885 A1 · SPUN-BONDED NONWOVEN FABRIC, FILTER MEDIUM, AIR FILTER, AND APPARATUS FOR PRODUCING FILTER MEDIUM

Abstract

A spun-bonded nonwoven fabric including composite fibers containing, as constituent components, a polyester-based resin P1, and a thermoplastic resin P2 having a melting point lower by 20° C. or more than the melting point of the polyester-based resin P1, in which at least a part of a surface of the composite fibers is the thermoplastic resin P2, at least some of the contact points between fibers of the composite fibers have a micro bonding area having a length of 5 μm or more and 100 μm or less in a fiber axis direction, an average single-fiber diameter of the composite fibers is 15.0 μm or more and 40.0 μm or less, and an average center-to-center distance between nearest neighbor fibers in a cross section in a transverse direction of the spun-bonded nonwoven fabric is 50 μm or less.

Claims7

Dependent claims

A spun-bonded nonwoven fabric comprising composite fibers containing, as constituent components,

a polyester-based resin P1, and
a thermoplastic resin P2 having a melting point lower by 20° C. or more than the melting point of the polyester-based resin P1,
wherein at least a part of a surface of the composite fibers is the thermoplastic resin P2,
at least some of the contact points between fibers of the composite fibers have a micro bonding area having a length of 5 μm or more and 100 μm or less in a fiber axis direction,
an average single-fiber diameter of the composite fibers is 15.0 μm or more and 40.0 μm or less, and
an average center-to-center distance between nearest neighbor fibers in a cross section in a transverse direction of the spun-bonded nonwoven fabric is 50 μm or less,
wherein the spun-bonded nonwoven fabric has regularly arranged macro bonding areas, and a shortest distance between adjacent macro bonding areas is 0.5 mm or more and 2.0 mm or less.

4 more elements

An apparatus for producing a filter medium comprising:

a first web forming assembly that forms a spun-bonded nonwoven fiber web;
a second web forming assembly that forms an electret melt blown nonwoven fiber web on the spun-bonded nonwoven fiber web to form a laminated web;
a first thermal bonding assembly that thermally bonds the laminated web to form a macro bonding area in the laminated web;
and
a second thermal bonding assembly that causes hot air to penetrate the laminated web to form a micro bonding area in the spun-bonded nonwoven fiber web,
wherein the first web forming assembly includes:
a spinning spinneret A having a plurality of discharge holes that spins out two kinds of thermoplastic resins melted in an extruder as composite fibers;
a drawing device that suction-draws the spun composite fibers with compressed air;
and
a collection device that collects the stretched composite fibers to form a spun-bonded nonwoven fiber web,
the second web forming assembly includes:
a spinning spinneret B of a non-electroconductive polymer having a plurality of spinning holes in a width direction;
and
a water sprayer for the spun yarn discharged from the discharge spinneret B, in which the water sprayer includes a plurality of water discharge openings arranged in the width direction and a pair of air discharge openings that opens either continuously or intermittently in the width direction and is located so as to sandwich the water discharge openings and is a spray nozzle configured to cause air discharged from the air discharge openings to collide with water discharged from the plurality of water discharge openings,
the first thermal bonding assembly includes:
either a pair of thermal embossing rolls with engraving applied to at least one roll surface, or an ultrasonic horn, and
the second thermal bonding assembly includes:
a conveying device for the laminated web, the conveying device including a drum or a belt;
a heating device for an atmosphere in which the laminated web is located;
and
an exhaust device that sucks and exhausts air
from a side of the conveying device opposite to a side with which the laminated web comes into contact.

19 more elements

Dependencies are inferred from the claim text.

Spun-bonded nonwoven fabric, filter medium, air filter, and apparatus for producing filter medium

Life of this patent

Spun-bonded nonwoven fabric, filter medium, air filter, and apparatus for producing filter medium

Life of this patent

Abstract

Claims7