DE4244904C2 - Bulky, nonwoven fleeces mfr., with stabilised surfaces - Google Patents

Abstract

A bulky nonwoven fleece material is made from longitudinally disposed fibres mmeandering between stabilised fleece surfaces. The apices of mutually adjacent meander arcs are connected to one another by fibre loops. The loops are made from fibres from the apices alinged crosswise to the meander arcs close to and parallel with both surfaces.

Description

The invention relates to a method for the production of a large-volume fleece substance, a device for carrying out the Process and a nonwoven fabric solidified by the process with fiber loops on both sides th surfaces and with a meandering shape between the Surfaces of the nonwoven arranged fibers, wherein a mostly longitudinal, layered Fleece fed continuously, in a defined position the layered fleece is deflected in a meandering shape and fibers from the, each facing a surface Parting the meandering arches drawn and with others Layers of fiber are engulfed.

There are processes and nonwovens mentioned above ten kinds in various forms. In practice, the bonding of nonwovens takes place in the large volume through the so-called needling voluminö fleece layers.

With the help of a large number of so-called ten felt needles many fibers across the fleece steers and there irregular with other fibers of the fleece moderately devoured.

To achieve a smooth surface on both sides the needling takes place simultaneously or in succession from both sides.

The number of punctures per unit area determines the Density and uniformity of the surface. If the surface is supposed to be smooth, a large number of Grooves should be provided per unit area.  

This makes the fleece quite stable, but also very tight, dense and over the entire cross section inelastic.

For upholstery purposes as well as for filters or insulation However, for purposes it makes sense to the inside of the fleece to provide material with a very low density and make the outer layer stable and smooth.

For this purpose, so-called spray Laminating process under several needled nonwovens different densities on each other.

These layered nonwovens produced in this way only have low elasticity across their surface. By applying binders they become rela tiv rigid and do not get involved for many purposes put.

If you connect the individual layers by needling, then you also automatically compress the inner curl re fleece layer and the nonwoven has essentially the same undesirable properties as a two needled thick fleece on both sides.

Such nonwovens require because of their high Dense a lot of material, they are heavy and stiff and are z. B. as sub-fabrics for upholstery in motor vehicles and also as a sound-absorbing body not lining with a customizable surface useful.

For such purposes one has therefore in the past non-woven fabric on the back of the qualitative high quality, patterned, often with a plush surface che provided outer fabric added.

These nonwoven fabrics have because of their low cross cuts an insufficient padding effect.  

For this reason you have under the fleece or as a replacement for the same one more layer Foam added. At the back you had to to ensure the necessary lubricity with the help of a binder is a thin, coarse-mesh thread git add ter.

This design makes the upholstery fabric at Siche The necessary quality parameters are very expensive agile.

In addition, the foam used is not recycled Eligible.

For other purposes, so-called fleece pile Products become known on the market under the names Voltex and Kunit.

The product "Voltex" is a Nonwoven fabric, in which the fibers of a nonwoven by means of Pushpins pulled through a base layer and open the right side of the goods into a composite of fiber material be put together.

A thick pile remains on the left side of the goods layer from the non-meshed nonwoven parts.

After brushing off the loose fleece parts you can go through Fixing and damping processes this pile layer in one stabilize voluminous condition.

This created surface is neither as Sliding surface for upholstery fabrics as a receiving surface for a customizable wear-resistant outer fabric suitable.

In the technology referred to as "Kunit" (DD 258 829 and DD 282 585) is a multi-layered, predominantly longitudinally oriented fleece meandering presented and unilaterally by meshing the meanders arches, through a base layer or in a jersey laying, solidified by fiber mesh formation.  

Such, one-sided solidified nonwovens are only very limited use.

Brushing out the loose fleece components and that Return to the process on the nonwoven machine not possible with the desired effect because the returned fibers lost their longitudinal orientation have won again only through a carding process can be.

EP 0 350 627 A1 describes a device for Making a voluminous fiber layer known has become a predominantly longitudinal Compress the nonwoven fabric in a meandering shape using a folding element tet and in this form of a hot air system for fixie ren is supplied.

With this device one arrives at a substance which has a low density and is elastic. However, this material is in this form for upholstery purposes completely unsuitable.

The surfaces are not slippery and firm. For Generating these properties requires additional, Apply stable fabrics. Here then the Disadvantages outlined above. They reached Elasticity benefits will reappear destroyed.

This limits the use of such products to such areas where you can also find loose fleeces could use.

British Patent 1 307 114 a Process for making a double-sided solidified ten nonwoven fabric shown in which a nonwoven layer in Change two needles arranged next to each other hen a fleece knitting machine is submitted.  

The latch needles penetrate the crown of the pre laid fleece folds, capture fibers and form there from it a fiber mesh layer.

As soon as the needles start to move, is created by folders over the neighboring tongue the next fold.

When this is finished, the next row of needles can be in penetrate the apex of this fold.

Such a procedure leads to a nonwoven that has stable surfaces on both sides and in the middle has loose and transversely oriented fibers. The across Oriented fibers give the nonwoven permanently high elasticity with large volume.

This way of working can be classified under economic acceptable, industrial conditions not reali sieren.

The interdependency of the individual work steps from each other and the possibilities of movement of the Fleece over the long ways only allows very low high working speeds. The procedure is not practicable. The desirable nonwoven is there not available.

EP 0 498 276 A1 describes a method for manufacturing position of mineral fiber boards become known, at the mineral fiber wetted with a binder felted by mutual bulging and in their thickness is compressed. In a continuous furnace hardens the binder while maintaining a level, smooth surface Surfaces of the fleece layer.  

In one embodiment, the felt is felted Fibers of the fleece with the help of so-called felt or Felt needles.

These felting needles penetrate from both surfaces of the Fleece one and can by arranging the hook difference or by different stroke sizes areas of the fleece more or less strong deflect and / or felt.

Such a way of working is for the production of Nonwovens that have a permanent, high elasticity should have high flexibility, not applicable. As mentioned at the beginning, it is not here either possible, loose fleece structures inside the fleece get fabric. The alternate needling of performs above and below in the presence of one curable binder to densify the fleece fabric that has a desirable elasticity and flexi completely excludes bility.

On the other hand, the curable binder also leads to Surfaces that are smooth and firm, but also stiff and are inflexible.

Nonwovens of this type cannot be used instead of use the usual foams.

It is an object of the invention to produce a method provision of an elastic and flexible nonwoven, with surface solidified on both sides and with hochela propose a core that is highly productive and low cost of materials can be realized. The density and thickness of the loose, elastic The middle class should be variable.  

According to the invention, this object is achieved by the in Proof 1 defined procedures on surprisingly simple Way solved.

By needling the fleece surfaces in parallel or at an acute angle to the fleece surface, a high Surface stability achieved without the Ela stity across the base is lost.

Can be used to manufacture highly stable, lightweight molded parts the nonwoven according to the invention deep-drawn in the area the dense surface layers with a plastic soaked and cured in a mold. In order to this nonwoven is also suitable for production of body parts.

The essence of this procedure is that the Solidification of the two surfaces of the meander fleece in two temporally and spatially separated Work steps are carried out.

The size of the temporal and spatial separation plays a role practically no role.

Regarding the device used, it has proven to be Proven useful for leadership and drive the necessary bars the basic structure of a chain to use knitting machine (claim 2).

A warp knitting machine can also be used instead of the warp needles are equipped with felting needles. The way these needles work, however, is the guidance of the fleece in front of these needles in parallel or to arrange at an acute angle to them. As a counter holders can use modified inclusion combs with their Drives can be used.  

The nonwovens produced by this process are particularly applicable where the gliding ability the fleece surface does not have very high requirements be put. The core remains in this process of the nonwoven fabric is loose and retains its high elasticity act.

These nonwovens are therefore particularly suitable for sound insulation or suitable for coverings in motor vehicles.

The invention is illustrated below in one embodiment game are explained in more detail. In the associated Drawings show:

Fig. 1: a consolidated nonwoven having genadel th web surfaces,

Fig. 2 is a schematic representation of the Vorrich device for producing a consolidated nonwoven according to Fig. 1 and

FIG. 3 shows a device according to Figure 2 used on warp knitting machines with horizontal needle bar and vertically movable holding-down or counter holding means..

A fleece coming from a card or card will by folding several nonwovens or by zigzag laying stratified along the conveying direction and usually compacted by rolling in such a form that it is suitable for further processing.

Its fibers are essentially longitudinal, without disrupting the presence of transverse fibers conclude.  

The average stack lengths of this fleece are between 40 and 70 mm. It is also convenient insert longer fibers.

This fleece is first layered in a meandering shape. The meandering arches have a length that is somewhat is greater than the thickness of the fleece to be produced fabric.

This resulting fleece is referred to as meander fleece 11 .

For the purpose of strengthening the surfaces of the meander dervlieses 11 , the apex 112 and 113 of the mutually laterally adjacent meandering arches are connected together.

According to Fig. 1, this connection is realized by fibers 13 , 14 , which are captured in a meandering arch, pushed across the apex 112 , 113 ben several meandering arches and are intertwined there by multiple piercing with felting needles.

An apparatus for producing the nonwoven fabric according to FIG. 1 is shown in FIGS. 2 and 3. In principle, these two devices are identical. They each have a vibrating fold layer 4 with a pair of rollers 42.

The pair of conveyor rollers 42 does not necessarily have to take part in the oscillating movement of the fold layer.

Two vibrating grippers 43 , 44 secure the meandering deposit of the fleece 1 in a guide channel 45 and ensure its gradual transport in this guide channel 45.

The guide channel 45 is bent at an obtuse angle in closely adjacent locations in opposite directions.

In this way, before and after the bend, the felting needles 51 , 61 , also called Veltin needles, can penetrate into the surface of the meander fleece 11 at an acute angle and move there parallel to the surface of the meander fleece.

Through the felting needles 51 , 61 , a plurality of fibers 13 , 14 are deflected across the apices 112 , 113 of the meandering arches and swallowed up with one another.

As an abutment, counterholders 52 , 62 which oscillate transversely thereto can be introduced into the fleece in the rhythm of the needle movements. During the return stroke of the felting needles 51 , 61 , the fibers 13 , 14 are stripped through the walls of the guide channel in the stripping zone 531 , 631 .

The arrangement according to FIG. 3 is chosen if you want to use the horizontal storage of the needle bar and its drive on warp knitting machines, in particular sewing knitting machines, for guiding and driving the felting needles 51 .

The solidified nonwoven is pulled off in all cases gene and a not shown winding or Feeders fed for temporary storage.

Reference list

1

Fleece, layered, lengthways oriented

11

Meander fleece

111

Meandering arches

112

Parting

113

Parting

13

Fibers, deflected

14

Fibers, deflected

4th

Folders

41

frame

42

Pair of conveyor rollers

43

Gripper

44

Gripper

45

Guide channel

5

first needle zone

51

Felting needle

511

Barre

52

Counterhold

521

Barre

53

Leadership area

531

Wiping zone

6

second needle zone

61

Felting needle

611

Barre

62

Counterhold

621

Barre

63

Leadership area

631

Wiping zone

Claims (3)

1. Process for producing a large-volume nonwoven

• 1. with surfaces consolidated on both sides by fiber loops and
• 2. with fibers arranged in a meandering fashion between the surfaces of the nonwoven,

in which

• 1. a predominantly longitudinally oriented, layered fleece ( 1 ) is fed continuously, in a defined position;
• 2. the layered fleece ( 1 ) deflected in a meandering shape
• 3. fibers are drawn from the apexes of the meandering arches, each facing a surface, and intertwined with other fiber layers,

characterized by
that a layered, longitudinally oriented fleece ( 1 ) is laid in a meandering manner by means of a pair of conveyor rollers ( 42 ) and is fixed and compacted in a guide channel with oscillating grippers ( 43 , 44 ),
that the meander fleece ( 11 ) in a guide channel, based on the feed plane, is successively deflected in two opposite directions, is guided in an arc and
that the meandering sheets ( 111 ) in the area of the outer sheet at an acute angle to the surface of the meandering fleece ( 11 ) in the puncture area by felt needle groups ( 51 , 61 ) with insertable counterholders ( 52 , 62 ) and wipers ( 531 , 631 ) are connected. 2. Device for performing the method according to claim 1, characterized in that
that a warp knitting machine known per se is permitted instead of the slider needles with felting needles ( 51 , 61 ),
that the warp knitting machine has two jobs and
that the fleece guide ( 45 ) in front of the felting needles ( 51 , 61 ) forms an acute angle to the longitudinal axis of the felting needles ( 51 , 61 ) and the counterholders ( 52 , 62 ) can be inserted transversely into the meander fleece ( 11 ). 3. Nonwoven fabric, produced by the method according to claim 1, characterized in that the fibers ( 13 , 14 ) which are devoured to consolidate the surfaces are aligned almost parallel to the surface of the meander fleece.