DE3021438A1 - METHOD FOR PRODUCING FLEECE MATERIALS WITH REFORMING CAPACITY - Google Patents

Description

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V5rskumny ustav textilnej chemie Zilina, CSSR

Process for the production of nonwovens with resilience

The invention relates to a method for producing nonwovens with resilience due to a a top fiber layer, a thermoplastic self-bonding intermediate layer and a fibrous backing layer existing needle goods.

Since such a nonwoven has a resilience, it is suitable for interior decoration in form of utility or decorative items, as molded insulating materials, molded wallpapering accessories for furniture, technical Nonwovens of the types of solidified so-called geotextiles, amelioration filters with resilience, shaped Textile fabrics for insulation and covers for the interiors of motor vehicles, ships, aircraft, railroad cars with shaped and at the same time patterned parts or the like.

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The term "textile product with resilience" is to be understood as such a flat structure that is not only is deformable, but retains the acquired shape.

The product deformation technology in the textile industry already has its tradition and is used both for plastic Patterning by two-dimensional deformation as well as for the production of textile compacts in the manner of three-dimensional Deformation applicable.

The term "two-dimensional deformation" means the formation of one and / or two-sided plastic ones Patterns, whereby the goods treated in this way are practically a two-dimensional fabric. In contrast, is under "three-dimensional deformation" the formation of three-dimensional To understand compacts.

The production of textile pressings by three-dimensional deformation is used for a specialized one Range of goods that z. B. deformed car carpets, textile sound and heat insulating underlayers, shoe uppers o. The like. and which can be produced in several ways. The first method is impregnation a fiber structure with precondensates of synthetic bitumens and their subsequent crosslinking under simultaneous deformation with a hot tool. The second method is by forming or laying down a thermoplastic eye Film or a thermoplastic fiber layer

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the back of the goods and through subsequent deformation of the goods at the plasticizing temperature of the thermoplastic used Fibers made with the help of a cold tool. The third method is to coat the Pad with a synergic mixture of thermoplastic and non-thermoplastic components in the form of Powder, flakes or fibers or shrinkable fibers and in their subsequent heat deformation using of a cold tool ..

As can be seen from the foregoing, the methods used consist of three-dimensional deformation exclusively in physicochemical processes, although offer very good results, but also have disadvantages. One of these can be, for example, at present Thermoplastic applications a relatively high Consumption of these substances (more than 50% by weight), the impossibility of patterning the top and the resulting ' following necessity of the mere patterning of the reverse side, a difficult balancing of the structure of textile goods or Mention the like.

On the other hand, the manufacturing technique of the plastically patterned textile fabrics has so far been more physico-based chemical processes and only sporadically on chemical surface deformation processes.

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Plastic patterned needle punched nonwovens have been practically since 1969 using the patents of the Sommer company of the needling machines with specially adapted base and stripping plates and with a new type of needle quality, whereby it has been possible to produce essentially three main types of needle goods patterned on the top, etc. Nonwovens with a corduroy-like rib structure, loop velor imitating velor structure and finally with pimple and simple pattern effects, especially excellent plastic pimples or simple straight lines Patterns to create.

Among the disadvantages of these types of plastic patterns However, there remains, for example, high needle stress and the resulting massive machine structures and lower performance compared to the smooth needle felt nonwovens, which in turn results in higher production, energy and other costs.

In addition to the mechanical production processes of patterned needle punched nonwovens have been used for the last decade also other principles applied to the production of sewing fabrics, in particular using a wide-meshed, three-dimensional or color-patterned textile layer on the top, by depositing pattern threads or webs in the form of loosely laid loops, patterns or the like on the top-side fleece layer, with the introduction of shrinkable Threads in the underlay, loops, knobs or lugs on the upper side as a result of thermal shock shrinkage forms a geometric pattern.

There are also methods of patterning by deforming surfaces practically all types of nonwovens, e.g. B. by

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Use of thermoplastics and bicomponent materials with resilience in the form of fibers, fiber structures, films, dispersions or plastics. All in this field However, known methods are only partially for the plastic patterning of the top by surface deformation etc. available for the reasons that the fibers and fibrous structures having recovery from the technical point of view specific products from a very narrow range of titers and colors are. Films, dispersions and plastomers are again only textile auxiliary raw materials contribute to the deformation of the top, but do not participate in the pattern.

In contrast, the inventive method solves for Production of nonwovens with resilience on the basis of needled pre-fabricated several problems and deficiencies of plastically patterned textile goods that are deformed both in two and three dimensions, either in separate ones Processes or in a single operation.

The test results show advantages by the method according to the invention for the production of Nonwovens with resilience due to an upper fiber layer, a thermoplastic intermediate layer and a fibrous backing layer consisting of needle-punched fabrics can be achieved.

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According to the invention, this method is characterized in that the pre-fabricated by coating a fiber layer of thermoplastic, serving as a binder fibers of low melting point, which are from 15 to 50 wt .-% of the nonwoven fabric, with single or multicolored nonwovens made of a mixture of Natural and / or man-made fibers with a melting point at least 20 ° C higher than the polymer of the thermoplastic fiber layer is produced, whereupon the two fiber fleece layers by needling from the back, ie from the single or multi-colored fiber fleece, using a greater penetration depth than the entire thickness of the two nonwoven fabric layers are joined together until the formation of a third dense, the thermoplastic fiber layer from the other side covering the upper layer, whereupon the Vorware as required further coated with fibrous layers by needle punching, stitch bonding or chemical bonding ^such u ™ final product joined together chemically be required is subsequently plasticized by dry and / or wet heat according to the melting point of the thermoplastic fiber layer and simultaneously or subsequently deformed under pressure with the aid of a tool in two or three dimensions, the die surface of the tool being provided with the negative of a plastic pattern as required , whereupon the resulting plastic pattern and / or the patterned compact is fixed by cooling the product to room temperature.

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Laboratory tests have shown that when a thermoplastic nonwoven e.g. B. of polyethylene fibers is coated with a fleece made of colored fibers with a ^{melting point at least 20 0} C higher than that of the thermoplastic fleece used and the two structures are needled in a conventional needle machine from the side of the colored fiber fleece, a new one on top of the product Pattern layer is created which covers the thermoplastic fleece and which thus comes into the middle of the preliminary product produced in this way. Such a blanket then represents a basis for the subsequent construction of the nonwoven fabric with resilience. With the blanket any further layer of fiber fleece, felt, stitch-knitted fabric, film or the like can be connected together by needling, stitching or binding, creating an end product with reshaping ability arises.

After heating the laminate produced in this way above the melting point of the thermoplastic used Fibers melts the latter fiber material, flows between the other fibers and anchors the roots the fibers of the actual front layer into a three-dimensional Skeleton of the melt.

A suitable regulation of the aforementioned heat treatment essentially results in an intermediate layer Impregnation through the thermoplastic melt, which chemically cross-links the core layer of the nonwoven caused at the level of impregnation with aqueous dispersions of film-forming polymers. the The upper pattern layer retains its textile-like character and at the same time gains excellent durability against all types of mechanical stress.

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By suitable regulation of the weight proportion of thermoplastic fleece in the nonwoven in the area from 15 to 50% by weight is the ability of plastic patterning or three-dimensional deformation with simultaneous plastic pattern can be achieved together with the resilience of the goods.

The nonwoven fabric according to the invention is impregnated with an interlayer - d. H. without further impregnation with aqueous dispersions - usable. If necessary, it can be covered with a suitable backing such as ζ. B. with a rub-in or application means without or in combination with felt, foil or the like - depending on the intended use of the product and the required air or water permeability. The field of application of the invention Products range from light goods with good permeability for filter materials to wallpaper, upholstery and Carpet fabrics to heavy goods for the manufacture of molded compacts, sound-insulating textile cassettes or the like

The invention has been investigated experimentally on needle-punched nonwovens and sewn-knitted fabrics.

It became a needle pre-fabric by coating one

raw polyethylene spun thread composite (150 g / m basis weight) with a fleece made of colored polyethylene fibers

2
(17 dtex; 400 - 500 g / m weight per unit area).

Needles 15 χ 18 χ 32 χ 3.5 EB were used for needling

used and the needling was carried out by the propylene

2 fleece side with an average of 60 punctures per cm and 15 mm penetration depth through. On the surface of the

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The polyethylene layer was created from the penetrating polypropylene fiber bundles a colored pole cover layer / which will be regarded as the upper pattern layer during the further process became.

Such a pre-product was used as a basic link with Rückformventiögen and used as a top layer for the further construction of the finished nonwoven fabric.

In the first attempt, the back of the pre-product was applied

Another polypropylene fiber fleece with a surface weight of 400 - 500 g / m 2 is needled. The needling was carried out under the same conditions as for the pre-fabric, but with 150 stitches per cm and 18 mm penetration depth. The top pile layer of the resulting product has become even more tight and has completely covered the polyethylene fiber layer. The product was treated subsequently in a laboratory drier at 130 to 140 ⁰ C for 5 to 10 minutes, wherein an intermediate layer-impregnation took place with the Polyäthylenfaserschmelze and thus a chemical reinforcement of the structure. After the product had cooled down, it was tested by comparing it with a similarly prepared felt product, but without the built-in polyethylene fiber layer; The latter was chemically strengthened by unilateral impregnation with an aqueous dispersion of vinyl acetate-butyl acrylate copolymer (20 wt .-% dry content) and 10 minutes at 130 to 140 ⁰ C dried.

The comparative information can be found in the table below:

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Dry content surface abrasion

the weight of the binder would increase in thickness

9 2 2

g / m ^z % g / m mm g / m%

Felt with a PE layer

according to invent .; Between-

layer impregnation 150 12.37 1222 7.06 56.0 4.58

with PE melt

Felt without PE layer;

Impregnation with

Butyl acrylate / vinyl 210 17.20 1220 7.01 59.3 4.86

acetate / dispersion

As can be seen from the results of the first experiment, that is after the abrasion test of the nonwoven fabric according to the invention Determined fiber decrease is lowest, although the dry content of the polyethylene fiber binder is up to 5% is lower than that with the dispersion of butyl acrylate-vinyl acetate copolymer impregnated felt.

In the second experiment, the formation of plastic patterns by two-dimensional deformation on the needle felt produced in the first experiment according to the invention was investigated. After a 5 to lOminiitigen treatment at 130-140 ⁰ C in a laboratory dryer such a needle felt was still in the hot state on a screen mat under pressure of a

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Patterning tool according to one of the known surface patterning techniques patterned. In the product, the strength of the fiber anchorage was determined by abrasion test and percentages the deformation, compressibility and recovery of the plastic pattern with permanent resilience checked.

Thick area Compres- Deforma- Erho- Abrasion from mm weight sensitization

%% g / m ² %

unpatterned felt

according to the 7.65 1196 30.96 16.92 5.975 56.30 4.70 invention

patterned felt

according to the 7.30 1193 37.98 16.71 6.510 51.33 4.30 invention

The test results show that the plastically patterned felt according to the invention according to the Surface deformation generally has better performance parameters than an unpatterned felt.

In the third experiment, the three-dimensional deformability of the felt goods according to the invention was tested with the same

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Checked their upper side in a timely pattern. For this purpose, the preliminary product produced after the first attempt was used; this contained the polyethylene fiber layer (200 g / m 2 surface weight) and the colored polypropylene fiber layer

(400 - 500 g / m basis weight). In the further process, the two uppers were layered against each other with their upper pile sides and the polypropylene fiber back with 150
needles.

with 150 punctures per cm and 18 mm puncture depth

The product was subsequently treated in a laboratory dryer for 5 to 10 minutes at 130-140 ° C. three-dimensionally deformed while still hot under the pressure of a cold or hot tool, the one with the felt top coming into contact surface of the die had the negative engraving of a plastic pattern. At the When the hot felt was pressed into the die, three-dimensional deformation occurred first and then after it was complete Impressions for the plastic pattern of the textile pressed part. The shape and pattern were then through Cooling of the compact fixed.

The recovery was determined by determining the percentage of shape deformation in the case of the present invention Compact in comparison with a compact without a polyethylene fiber layer, which with a dispersion of thermoplastic butyl acrylate vinyl acetate copolymers sat was impregnated, as well as with common sewn-knitted fabrics Pressings that have a polyethylene film in the backing

+ 2 spun thread composites with a weight per unit area of 1000 - 100 g / m included, evaluated.

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The results can be found in the table below.

Fiber content in the product

For resilience and ange-shaped component used as a binding agent turned in% to

Heat 1 '10' 60 '48 St.

Polypropylene fibers
(800 g / m ² )

Butyl acrylate-vinyl acetate mixed polymer - order: 30.8% dryness dry 24.6 24.6 34.0 92.8

Polypropylene fibers
(650 g / m ² )

on the back
of the goods lamination wet

ter polyethylene (steam) 24.6 24.6 24.6 25.0 composite spun thread
(1000 g / m ² )

Polypropylene fibers
(...-800
g / m ² )

Polyethylene spun thread composite (400 g / m ² ) built into the goods, dry 24.6 24.6 24.6 25.0

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From the comparison it can be seen that the deformed compact produced according to the invention - despite

the economical use of only 400 g / m 2 of the thermoplastic binder on the polyethylene basis - a practical one excellent resilience as conventional

2 'borrowed technologies using up to 1000 g / m of des Polyethylene fleece offers. The polypropylene felt, which is only impregnated with a thermoplastic dispersion, has only a slight appearance Resilience on.

The method according to the invention is furthermore intended to in no way limit the scope of the invention on the basis of additional ones Embodiments are explained in more detail.

example 1

To produce a plastically patterned needled floor covering, a preliminary product was made from a Mixture of polypropylene fibers, consisting of 50 parts of 17 dtex fibers, 20 parts of 30 dtex fibers and 30 Divisions of 70 dtex fibers, prepared. The length of cut was 90 - 130 mm.

The mixture was minced, dissolved and made into a

2
Fleece with a surface weight of 400 g / m 2 processed by a common spinning process. This structure was then used to create a raw polyethylene spun thread composite (150 to

2
200 g / m surface weight) and needled from the side of the polypropylene fiber layer with needles of 15 χ 18 χ 32 χ 3.5 RB with 60 to 70 punctures and 15 mm puncture depth. This structure represented a preliminary product in relation to the end product.

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At the same time, the same polypropylene fiber fleece was produced under the same conditions, but without a polyethylene layer, assigned to the back of the above-mentioned pre-fabric and with it by needling with the same type of needle with 150
deep connected.

2 needle type with 150 punctures per cm and 18 mm puncture

The needle laminate obtained in this way with a pile surface could be subsequently applied from the rear side with a fixing or weighting, rub-in or mounting

2
Carrying agents of 200 g / m dry content and more - depending on the required weight and stiffness of the product - can be treated. The product was then dried, plasticized and at a temperature from 130 to 160 ⁰ C to the melting of the Polyäthylenfaserschicht directly patterned in the hot state by means of a stamping tool according to the prior art.

The plastic pattern formed on the nonwoven fabric was fixed by cooling it to room temperature. The end product was cut to size, possibly made up, packed and dispatched.

Example 2

for the production of so-called calibration felts with minimal Dxckenschwenken for documents of heat-insulating PVC floor coverings, wallpapers or the like. With smooth or patterned upper side was a preliminary product made of 100% wool-like or carpet-like fiber types or from their Mixtures with fibers prepared from chemical materials (see Example 1).

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Such Vorware was at 130 - 140 ⁰ C plasticized and directly pressed an embossing calender in a hot state between smooth cold rolling. The distance between the rollers was set to half the thickness of the plasticized felt. If a plastically patterned product was to be obtained, the pressing process was carried out between relief patterned rollers of the embossing calender under a pressure of about 2 tons.

The compacted felt with the smooth or patterned Top side was stabilized by cooling to room temperature. The end product was as in Example 1 adjusted.

Example 3

For the production of plastically patterned sewing fabrics with strung loops, a preliminary fabric was used Coating a thermoplastic polyethylene spinning

2
thread composite (100 g / m basis weight) with a

Fleece (250 g / m surface weight) made from colored polypropylene fibers (17 dtex or more). The two structures were connected by needling (see example 1) .

2 At the same time, a fleece (130 g / m 2) made of 70 parts was produced

of high-shrinkable polyvinyl chloride fibers and 30 parts prepared from polypropylene fibers of common woolen denier. The structures were finely pre-needled.

The pre-fabricated fabric and the shrink fiber fleece were tied through parallel wales in a fringed weave with shrink-wrapped

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capable silk joined together on a stitchbonding machine according to known technology.

The sewing material obtained in this way was then shrunk and at the same time on a shrinking device with live steam at 150 °
fied.

at 150 - 180 ⁰ C and under pressure of 6-10 kp / cm plastic

The shrunken sewing material was fed directly into a pattern calender in the hot state and the Lined loops were deformed transversely, geometrically or otherwise to give interrupted figures according to Example 1.

Example 4

For the production of textile soil filters for melioration od. The like. Or geotextiles with reshaping ability a preliminary product by layering a textile fiber mixture from secondary raw materials (3.0 to 30 dtex), in particular on a chemical or synthetic basis, prepared. There were z. B. 70 parts of shredded textile materials from ready-made garbage (3.0 to 6 dtex) mixed with 30 parts of primary fibers based on polypropylene fiber (17 dtex). With

2 such a mixed fleece with a surface weight of 200 g / m 2

a raw spun thread composite with a weight per unit area of 100-200 g / m coated and the whole thing from the side of the

2 mixed fleece with 80 - 90 punctures per cm and 13-15 mm puncture depth needled. The thus prepared Vorware was subsequently plasticized at a temperature of 130-140 ⁰ C to melt the polyethylene layer, and then cooled.

For purposes of amelioration filters, the product cut into longitudinal webs of the required width, according to

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If necessary, plasticized again and shaped into an amelioration tube. An alternative type is the combination the plasticization, the subsequent deformation into the pipe and the final welding using the thermoplastic nonwoven component according to the usual technological processes.

Example 5

For the production of three-dimensionally deformed, sound and heat insulating sub-layers, of deformed Components of sofas, seating, etc. Furniture products, of technical compacts or the like., Was in the preparation of the preliminary product in the same way as described in Example 1, proceeded, with the exception that colored propylene fibers (30 dtex), possibly with 10 to 90 parts of dissolved fibers from secondary raw materials mixed, were used. The preliminary product was by coating a polyethylene spun thread composite

2
fabric (150 - 200 g / m basis weight) with a fleece

from the aforementioned fiber mixture (250-400 g / m basis weight) and by subsequent needling of the two structures from the side of the mixed fleece with 80 to 90 single

2
prepared per cm and a penetration depth of 13 to 15 mm.

If required, the preliminary product was also given a stiffening finish with spray or liniment, preferably based on a thermoplastic dispersion Polymer (15 to 25 wt .-% dry content) provided, dried, at the melting point of the polyethylene fiber layer plasticized and under pressure of a cold tool for required compact deformed. The shape of the compact

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was fixed by cooling. Finally, the pressed part was cut to size, made up, packed and dispatched.

Example 6

For the production of three-dimensionally shaped compacts For the interiors of automobiles, ships, vehicles or the like, a needle pre-fabric according to Example 1 with a fleece made of colored polypropylene fibers (up to

2
400 g / m basis weight) and a raw polyethylene

2 prepared spun thread composite (up to 200 g / m). The two fiber structures were then from the side of the polypropylene fiber layer by needling with 60 to 70 single

Chen per cm and 13 to 15 mm penetration depth connected together. Subsequently, two such preliminary goods were placed on top of one another with their upper pole faces and from the back by needling with 150 settings:
stitch depth connected together.

by needling with 150 punctures per cm and 18 mm

The thus prepared nonwoven fabric having stretch recovery was further at the melting point of the Polyäthylenfaserschichten, ie 130 - plasticized 140 ⁰ C, whereby a thorough interlayer impregnation with the Polyäthylenschmelze under formation took place the goods core of a three-dimensional skeleton of the melt. The final product was finally cooled and cut or chopped into sheet pieces suitable for deformation.

Such pieces were plasticized by wet or dry heat and then immediately after one of the usual Techniques pressed into a mold under pressure. The shape of the compact was fixed by cooling to room temperature carried out. The pressed part was subsequently added

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cut, assembled, packaged and dispatched. Example 7

In the production of three-dimensionally deformed and at the same time plastically patterned compacts in one The only operation was the manufacturing technology of the Pre-fabricated goods and the entire non-woven fabric with resilience - including plasticization and deformation in accordance with Example 6 followed.

The only difference was in the preparation of the forming die, the one with the top of the compact comes into contact and which is provided with the negative of a pattern to be given to the upper side of the compact is.

The deformation of the compact took place in two phases. In the first the plasticized goods were under Pressure of a tool drawn into the mold and too three-dimensional Shape deformed. In the second phase, the tool was pushed into the mold the formation of the corresponding two-dimensional plastic pattern on the upper side of the compact takes place.

The cooling and adjustment proceeded according to Examples 1 and 6.

Example 8

For the production of three-dimensionally deformed loop stitching materials for interiors of various types Means of transport became a pre-product by coating a thermoplastic polyethylene-spun-thread composite

2
j / cm) with a

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fabric (400 - 600 g / cm) with a fleece made of carpet

2 gen polypropylene fibers (200 - 300 g / cm weight per unit area) prepared. The two structures were joined together by needling, as in Example 1, with a puncture depth of 15 to 18 mm .

At the same time, a stitch-bonded or active substance with a color-patterned loop or velor top was chosen prepared carpet-like fibers or filaments according to known technologies.

The preliminary product was thermally melted on one side in the usual way and with the upper pattern layer connected by compression between calender rolls to form sheets with resilience.

Such a nonwoven fabric with resilience and with a stitch-knitted or knitted patterned top was subsequently plasticized by wet or dry heat, three-dimensionally deformed into the required compact and adjusted according to example 1.

In the case of plasticization by wet heat, the compact became air and water permeable. In contrast could in the case of plasticization by dry heat, the compact - depending on the degree of melting of the Polyethylene fiber layer - to become impermeable to air and water.

Thus, the invention enables a method for producing nonwoven fabrics with stretch recovery due to a needled Vorware formed such that a nonwoven fabric made of polyethylene fibers as a binder with one or more colored nonwoven fabric of at least 20 ⁰ C higher

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Melting point than that of the applied polyethylene fibers coated is, whereupon the two layers of fleece by needling using a higher penetration depth than the entire thickness of the layers until a third layer is formed, the polyethylene fiber layer from the other side covering layer are connected together. The preliminary product prepared in this way is also layered and after If required, bonded together with other layers to form an end product that can be plasticized and deformed by heat.

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Claims (3)

Expectations I1.J Process for the production of nonwovens with resilience on the basis of an upper fiber layer, a thermoplastic self-binding intermediate layer and a fibrous backing layer consisting of needlework, characterized, that the preliminary product by coating a fiber layer of thermoplastic, serving as a binding agent fibers with a low melting point, which is 15 to 50 wt .-% of the nonwoven fabric, with single or multicolored nonwovens made of a mixture of natural and / or man-made fibers of at least 20 ⁰ C higher melting point than the polymer of the thermoplastic fiber layer is produced, whereupon the two fiber fleece layers are sealed by needling from the back, ie from the single or multi-colored fiber fleece, using a greater penetration depth than the entire thickness of the two fiber fleece layers until a third layer is formed, The top layer covering the thermoplastic fiber layer is connected together from the other side, whereupon the preliminary product is further coated with fibrous pattern layers as required, connected to the end product by needle-punching, stitching or chemical bonding, chemically treated as required, subsequently by drying or wet heat plasticized according to the melting point of the thermoplastic fiber layer and at the same time or after 233- (S 9733) -Nb-E 0300S1 / 08QB ORIGINAL INSPECTED 302H38 wearable under pressure from the top or back with the help of a tool two and / or three-dimensional is deformed, the die surface of the tool is provided with the negative of a plastic pattern as required, whereupon the plastic pattern created in this way and / or the patterned compact is fixed by cooling the product to room temperature. 2. The method according to claim 1,
characterized, that for the plastic pattern by two-dimensional deformation of the top a 15 to 30 wt .-% of the nonwoven fabric amount of polyethylene fiber fleece is used. 3. The method according to claim 1,
characterized, that for the three-dimensional deformation and the plastic patterning of the top in a single. occurrence a nonwoven polyethylene fiber comprising 30 to 50 percent by weight of the nonwoven fabric is used. D30051 / 080S