Process for producing a nonwoven material, plant for implementing it and nonwoven thus obtained

Abstract

This invention concerns a method and an installation for producing a spunbonded fabric, characterized in that it consists in: producing a spunbonded lap (5) against the surface of which is delivered at least a web (V1 and / or V2) of discontinuous fibers, obtained by carding. The formed complex is compacted by pressing and is continuously transferred onto a line (10) for water jet binding treatment, driving the fibers in the direction of thickness, the fibers which are bound together like a splice between and around the continuous filaments while remaining visible at the surface. After drying, the final product is obtained.

Description

[0001] For decades proposals have been made to replace conventional textile webs (wovens and knits) with structures called "nonwovens" which, in general, may be classified in three broad categories, resulting from their actual manufacturing process, namely:[0002] those called "wet-formed" nonwovens, produced using a technology similar to the manufacture of paper;[0003] those called "dry-formed nonwovens, consisting of discontinuous, natural or chemical fibers obtained by carding, napping or any other textile preparation equipment;[0004] those called "melt-formed" nonwovens, consisting of continuous chemical filaments and usually referred to by the generic name of "spunbond".[0005] The present invention relates to a way of improving the technology for producing such nonwoven webs of "spunbond" type and relates more specifically to a process, a plant and a novel type of product obtained by implementing these means, which product has the appearance and the properties, such as the handl...

AI Technical Summary

Benefits of technology

[0044] With regard to the grammage of the sheets(s) of discontinuous fibers which are combined with the spunbond web, this may vary depending on the applications but will advantageously be between 10 g / m.sup.2 and 50 g / m.sup.2, a sheet having a grammage of less than 10 g / m.sup.2 not allowing the spunbond web to be correctly bonded, whereas a sheet having a grammage greater than 50 g / m2 reduces the economic benefit of the process.

Problems solved by technology

By contrast, their use in the field of conventional textile applications, such as clothing, disposable garments, wiping materials, furnishing, interior textiles, etc., has not been developed since bonding by calendering, which causes partial thermal bonding of the fibers, without degrading the mechanical properties of the product, does however destroy the pliancy, the handle and the textile appearance.

On the other hand, at least to the knowledge of the Applicant, these needle-punching techniques have never been proposed for the purpose of solving the problem of the consolidation of a "spunbond" web as such, while still giving such a web the characteristics of conventional textiles, namely pliancy, handle, etc.

This is because if a needle-punching treatment using barbed needles were to be applied to a "spunbond" web alone, this might result in the continuous filaments of which such a web is composed being broken and, consequently, this may degrade the mechanical properties, which are one of the main advantages of such materials.

With regard to the use of a conventional bonding treatment using fluid jets, especially water jets, such a technology has not been adapted since it is well known that, in such spunbond webs consisting of continuous filaments the latter are difficult to move with respect to one another.

As a consequence, it is virtually impossible to envisage obtaining, using such a technology, a "spunbond" web having a level of cohesion comparable to that obtained by calendering, and to do so without impairing the mechanical properties of the material.

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