Fabric Comprising Shaped Conductive Monofilament Used in the Production of Non-Woven Fabrics

Abstract

In an apparatus for the production of a non-woven web, structure, or article using a spun-bonding process in combination with a forming fabric which is woven having flat CMD yarns, flat MD yarns or both with some or all of such yarns being conductive so as to dissipate static electricity.

Description

CROSS REFERENCE TO RELATED APPLICATION [0001]This application is a continuation of U.S. patent application Ser. No. 10 / 142,512 filed May 9, 2002, the disclosure of which is herein incorporated by reference.FIELD OF THE INVENTION [0002]The present invention is directed towards a fabric used in combination with a melt-bonding apparatus to form, transport and bond a web into a non-woven fabric.BACKGROUND OF THE INVENTION[0003]There presently exists apparatus for the production of spun-bond webs, structures or articles formed from filaments or fibers typically made from a thermoplastic resin. Such an apparatus is disclosed in U.S. Pat. No. 5,814,349 issued Sep. 29, 1998, the disclosure of which is incorporated herein by reference. These typically include a spinneret for producing a curtain of strands and a process-air blower for blowing process air onto the curtain of strands for cooling the same to form thermoplastic filaments. The thermoplastic filaments are then typically, aerodynami...

AI Technical Summary

Benefits of technology

[0012]It is therefore a principal object of the invention to provide for the production of non-woven webs, structures or articles through, for example, the melt-bonding process, which minimizes air leakage, particularly that caused by the forming fabric.

[0013]It is a further object of the invention to provide for a forming fabric for the production of non-woven webs, structures or articles that minimizes or eliminates web flutter.

[0014]A yet further object of the invention is to provide for a forming fabric for use in the production of non-woven webs, structures or articles which provides for the effect of static electricity during production.

[0015]These and other objects and advantages are achieved by the present invention. In this regard the invention is directed towards generally a forming fabric for use in the production of non-woven webs, structure or articles. The forming fabric comprises a woven structure having flat monofilament yarns in at least either the machine direction or cross machine direction. The use of the flat yarns in the forming fabric improve the fabric surface and decrease the empty volume in the fabric. The forming fabric may be single or multi-layered and is directed towards decreasing the disturbance caused by air whilst maintaining the desired permeability of the fabric. In addition, so as to address the static electricity problem, the flat monofilaments can be made of a conductive material which allows the dissipation of the static electricity on the web through the forming fabric to ground.

Problems solved by technology

In high speed operations with high air flow, air leakage can occur between the top press roll and the forming fabric surface or through the fabric itself.

Air leakage can result in undesired disturbance to the formation of the web.

Excessive air carried by the fabric during web transportation may result in causing the web to flutter.

In addition, in a melt-bonding process (which incidentally can produce spun-bond or melt-blown or any combination of the two), there is a large amount of static electricity generated.

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