DE7003945U - FIBER-FIBER-BASED KNUCKLE LEATHER. - Google Patents

Description

Carl Freudenberg Company February 3, 197o

694-0 Weinheim / Bergstr. ON 547a

Crumpled leather on a fiber fleece basis

It is already known to make natural leather by folding and crumpling it in various directions can be provided with longitudinal or transverse folds that create a regular or irregular pattern on the leather surface form. The crumple effect can be increased by staining the leather surface in different ways. By the Crumpling practically does not affect the quality of the leather. The crumple is only used to create a optical effect in natural leather.

It is also already known to provide fabric with a film and then to fold this two-layer structure again and to crumple, whereby the surface film is broken again, so that numerous folds arise, which then also create the effect of a crumpled leather.

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Lately the so-called fiber fleece artificial leather have become more and more important because they - how natural? Leather - breathable and have a leather-like handle. Shoe upper leathers are therefore already produced on the basis of non-woven synthetic leather.

For this purpose, a fiber fleece is impregnated with a coagulable one Binder. After this binding agent has coagulated, it is then dried, resulting in a nonwoven fabric. Will be the same then on a surface with a permeable? iü, especially polyurethane film.

The manufacture of the non-woven fabric is in the book "Ullmann's Encyclopedia of Technical Chemistry", Volume 11, 196ο on pages 622 - 624. The subsequent application a cover or coating film is used in I.e. on the pages 624-627.

One could now think of also using one for such synthetic leathers provided with a cover layer and based on fiber fleece To achieve a crumple effect by using the synthetic fiber leather, which initially has a smooth top layer after production, to crumple and crumple.

Immediately after crumpling the surface does indeed look a bit crumpled. As a result of the special properties of the substrate (non-woven synthetic leather) on which the cover film

rests, decrease or widen, but with The introduced wrinkles wear again after a few hours.

So it is not possible with coated synthetic fiber fleece to achieve the desired permanent optical effect by simply crumpling.

It has now been found that such a crushing effect is certain Measures can already be generated during the production of the synthetic leather substrate.

For this purpose, a fiber fleece, preferably after needling, first shrunk a lot. The area shrinkage should be at least 2o%, but preferably 5o #. Even higher Area shrinkage is possible, even if it is not absolutely necessary to produce the crumple leather effect. Afterward this fiber fleece is first impregnated with a coagulable binder using known methods. This will turn out to be Distribute the binder evenly in the fleece.

The binder is then again displaced at certain points on the fiber fleece. Have these certain places preferably in the form of long irregular stripes.

It is easiest to use the impregnated fiber fleece with j

ι to drive a pressure roller that has a vein-shaped raised

Pattern bears. This vein-shaped pattern already imitates the ί

Wrinkles in the crumpled leather. Along the raised veins is now I displaces the binder, so that a fleece is formed in which f

the binder is distributed unevenly.

Along certain vein-shaped lines is located in the extreme case no binder at all, while there is overconcentration within certain areas bounded by the veins. The binder is only coagulated when this state is reached.

Further treatment then takes place as usual. So you can first wash out non-coagulated binder components and then dry the fleece. This substrate, which initially feels like normal synthetic leather and its properties largely resembles this synthetic fiber leather, is then applied by one of the known processes, e.g. by the "counter coat process", coated with polyurethane.

As a result of the uneven distribution of the binder in the non-woven synthetic leather the surface will not be smooth, but rather have a vein-shaped mesh like that of the pressure roller is equivalent to.

in order to improve the optical ϋϊίβκχ even more, this material, which is already clearly structured on the surface, can be pressed and crumpled again in the usual way.

example

A fleece consisting of

a) 7o io rayon and 3o i "heat-shrinkable polyester fiber

b) 7 ο io polyamide and 3o % polyester shrink fiber

with a square meter weight of 2oo g is needled, then shrunk. The area shrinkage is 45 - 50 #. According to this, the weight of the goods after shrinking is 44o - 5oo g / m². Is impregnated with a commercially available, heat-sensitive colored Perbunan mixture (N 4 M from Farbenfabriken Bayer), with a wet absorption of approx. 150 $>. Subsequently, the non-woven fabric between two patterned heated rolls is treated as follows%

The rollers have a vein-shaped pattern that appears on the rollers is applied raised. The rollers are heated externally with gas (approx. 25o °). This will remove the raised areas from the Rolling the mixture first displaced according to the pattern and then precipitated. Temperature and speed are to be coordinated with one another. The material is then quenched in a cold water bath and non-coagulated binder or auxiliary agent is washed out. After the subsequent drying, a flat structure is obtained which has the pattern of the on both sides

Has rollers. The upper and lower gap are to be used in the same way (on conventional leather splitting machines). Through this Impregnation gives a voluminous base material for further refinement (crumple varnish).

This material produced in this way is then coated with polyurethane in the "counter coat process". Edition: 50 g / sqm. The material is then gently crumpled. This gives the material an irreversible crumple effect. This Material can be used as synthetic bags, shoe materials and clothing leather.

The two enclosed samples are crumple leather according to the innovation.

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Claims (1)

Claim to protection Crumpled leather, consisting of a fiber fleece in which the binding agent is nonuniformly in a coagulated form and one Top layer.