FR2471430A2 - PROCESS FOR THE PRODUCTION OF A NON-WELDED FUSED WIRE BASED TABLET ON A BOSSELEE SURFACE MOVING DISTANCE FROM THE WIRED LINE - Google Patents

Abstract

PROCESS FOR THE MANUFACTURE OF A NON-WOVEN TABLECLOTH BY SPINNING IN A MELT STATE ON A BOSSED SURFACE MOVING AT A DISTANCE FROM THE DIE. THE BUSHING AND THE BOSSELEE MOBILE SURFACE EXECUTE A RELATIVE CIRCULAR MOVEMENT IN RELATION TO ANOTHER, SO THAT THE WIRES ARE DEPOSITED BETWEEN AND AROUND THE BOSSES.

Description

Process for the manufacture of a spunbond nonwoven web

melting on a bumpy surface

  moving away from the die.

  The main patent No. 76 20902 of July 8, 1976 relates to a process for the manufacture of a nonwoven web consisting of wires with a diameter of 0.2 to 1.5 mm by extrusion

  of a synthetic polymer melt through a com-

  carrying a multitude of spinning orifices of a larger diameter

  approximately 0.2 mm in the substantially vertical direction on a movable surface at a distance of 3 to 20 cm, preferably 3 to 9 cm compared to the die, which surface has a bumpy profile with bumps of about 5 to 70 mm in height and which is cooled, the wires emerging from the spinning orifices being deposited by crossing each other in places on and between the bumps and being welded together.

  at their crossing points.

  The nonwoven webs produced by this method have a high weld point strength and increased transverse strength, but also withstand high compressive stresses. They are particularly suitable as support plies for soil and surfaces of heavily stressed turf, as erosion protection plies, as tablecloths for consolidation of embankments, dikes, banks, etc., as immersed plies for consolidation in hydraulic construction, as a channel layer in the

  drainage plies especially for vertical drainages.

  Also as a replacement material for straw, especially in stables, the product produced by the process

  according to the main patent has already given excellent results.

  In this field of application, the nonwoven web is subjected to a permanent alternating stress in compression, in

  particular in the case of breeding stables in the

  which cattle must remain standing for quite a long time

  periods of time. What matters here is a faculty parti-

  high elastic recovery or resilience of the nonwoven web, that is to say that its thickness after repeated loading and discharging under the effect of the hooves of

  animals must return to its original value.

  It is therefore an object of the present invention to provide a process for the manufacture of nonwoven webs

  having a high elastic recovery capability.

  The invention is based on the assumption that a coil-shaped disposition of the coarse yarns in the ply leads to a high elastic restoring force, since the yarns in the event of compression of the ply are no longer stressed in bending. but in torsion and are less deformed. The proposed overall solution therefore consists of depositing at least a portion of the coarse threads so as to obtain similar three-dimensional spatial shapes

to coil springs.

  To achieve this result, the method according to the main patent No. 76 20902 has been improved according to the invention so that the die and the moving surface having the bumpy profile perform relative to each other a relative circular motion so which son are deposited

  partly also around the bumps.

  Thanks to the relative circular movement of the die and the movable surface relative to one another, the different threads are deposited, in the manner of a lasso, also around the bumps of the moving surface so that they form a three-dimensional configuration similar to a spring

helical.

  The circular relative movement can be obtained by the fact that the moving surface executes a plane circular displacement. As this solution is technically very complicated, it is preferable that it is the die that performs a displacement

circular.

  The process for printing the die a movement

  circular is already known (German Patent Application 109 682).

  With the known method, in this way a three-dimensional textile material is produced in nonwoven webs of endless spun yarns deposited in a determinable order and in accordance with a drawing. In the textile materials thus produced, the compressive strength and the elastic recovery capability

do not play any role.

  It is certainly also known to manufacture by means of

  of rotating dies of materials in three-dimensional

  in which the yarns are in the form of helical springs separated from each other by traction (Japanese Patent Application 77 152 476). In case

  compression, this three-dimensional structure

However, it collapses.

  It is only the combination of the bumpy structure of the products made by the method according to the main patent and the helical spring structure obtained by the method according to the invention which gives a non-woven web resistant to compression and having a faculty. of recovery

high elasticity.

  As already mentioned in the main patent No. 76 20 902, it is advantageous for the web structure

  that the threads are also animated by a movement of va-and-

  To this end, the die and / or the movable surface can be moved back and forth transversely to the direction of the

displacement of the moving surface.

  To promote a removal of the son also around the bumps, it is necessary that they are preferably

truncated cones or pyramids.

  With the process according to the invention, it is possible to spin the synthetic polymers mentioned in the main patent. Due to its high specific gravity, however, it is preferable to use

  polyester, polyethylene-ephthalate particularly suitable for

  good for this purpose. This gives an increase

the compression module.

  As the deformation of the wires decreases and the elastic recovery increases as the diameter of the wires decreases (assuming the same weight and thickness of the web), wire diameters of 0.2 to 1.0 mm are preferred. (ie in the lower zone diameters reaching from 0.2 to

1.5 mm).

  As, moreover, for the same layer thickness, the increase in the density of the yarn and, consequently, in the weight of the sheet, increases the compression modulus, it is necessary for the quantity of molten polymer to be adjusted preferably so that the band

2471430.

  produced sheet has a weight per unit area of

500 to 1500 g / m2.

Claims (6)

  1. Method according to claims 6 and 7 of the patent   No. 76 20 902 of July 8, 1976, for the manufacture of a nonwoven web consisting of threads of a   diameter of 0.2 to 1.5 mm by extrusion of a synthetic polymer   molten through a die having a plurality of spinning orifices having a diameter greater than about 0.2 mm in the substantially vertical direction on a moving surface at a distance of 3 to 20 mm, preferably 3 to 9 cm, of the die and which has a bumpy profile with bumps of about 5 to 70 mm in height and is cooled son leaving the die orifices settling by crossing each other in places on and between the bumps and being soldered between them at their crossing points, characterized in that the die and the moving surface having the bumpy profile perform relative to each other a circular relative movement so that the wires   are also partly deposited around the bumps.   2. Method according to claim 1, characterized in that the die or the moving surface are animated in a known manner by a movement back and forth transversely to the sense   moving the moving surface.   3. Method according to claim 1 or 2, characterized in that the bumps are in a known manner trunks of cone or pyramid.   4. Method according to any one of the claims   1 to 3, characterized in that as synthetic polymer   a polyester, preferably polyethylene terephene, is used Talate.   5. Process according to any one of the claims   1 to 4, characterized in that the diameter of the wire is 0.2 to 1.0 mm.   6. Process according to any one of the claims   1 to 5, characterized in that the amount of molten polymer fed is made so that the nonwoven web   produced has a weight per unit area of 5oe to 1500 g / m2.