DE2107887A1 - Process for the production of a fiber composite with a relief-like structure and fiber composite produced by the process - Google Patents

Description

Process for the production of a relief-like structured fiber composite and produced by the process

Fiber composite

The invention relates to a method for producing a fiber composite with a relief-like structure and to a fiber composite produced by the process according to the invention. It is based on those known processes in which a nonwoven fabric is applied to a web-like, sieve-like Openings having or slotted carrier made of a thermoplastic material is placed, needled through it and the needled surface structure for further consolidation at least until the sheet-like structure has softened The carrier is heated.

In a known proposal (French patent specification 1,372,057), this heating of the sheet-like structure is controlled in such a way that the thermoplastic material of the carrier melts. The softening of the support material is selected so that the fiber material, if it consists of Kunetstoffasern not yet softened when the melting temperature of the substrate is reached. After solidification, the latter then serves as a binding agent between the fibers of the fiber material. According to the information provided by

TU9836 / 0995

Dipl.-tng. Heinz Etc. Patent Attorney D - 8 Munich 81. Cosimastra6 81 Telephone: (0611) 48 38 20

Patent specification relatively heavy and rigid product can be used as a thermoformable mold plate for the production of spatial Fabrics are used. A relief-like structuring of the surface is not intended, however.

A proposal pointing in this direction for the production of a fiber composite material with a weakly structured surface (Corrugation) comes from the French patent specification 1 352 377. This involves the production of bed sheets with cellulose and plastic as the starting material. A thin plastic fabric serves as the carrier material, possibly also a plastic film. As the cellulosic material is deposited on the support and applying heat is only pressed against the carrier, the process is limited to very thin layers of material. If the outer Layers and surface veneers are applied, it is suggested that to provide the surfaces of the fabric with grooves to prevent crackling. The corrugation of the However, surface film does not yet give the product a textile appearance.

The invention has set itself the task of creating a fiber composite, the surface of which is structured in a permanent relief-like manner , without hardened binder surfaces pressed against the surface and reflecting the light impairing the textile appearance of the surface.

The method according to the invention for the production of a relief-like structured fiber composite in which a fiber fleece

109836/0995

2 1 η 7 8 R

Dipl.-Ing. Home Lesser. Patent attorney O - 8 Mün * »n 81. Cosimastrafce 81 Telephone: (08ΤΠ 48 38 20

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Placed on a web-shaped, screen-like openings having or slotted support made of a thermoplastic material, needled through this and the needled sheet is heated for further solidification at least until the web-shaped carrier softens, is characterized in that the needled sheet, while the sheet-shaped carrier is still in softened state is, so between two tool surfaces, of which at least one has wart-shaped or burr-shaped elevations, is pressed together that the fibers not located in the area of the openings or slots of the carrier, with the exception of those located on the surface of the planar structure, in bundles detach n rriiger;?.. the plastic of the carrier after your fiber composite heat _# is removed so that the softened carrier again solidifies before the embedded therein under pressure fibers äjsris due to their ormerholungsv ^ r 'from de are embedded, can*

The method according to the invention is to be distinguished from the known methods of forming felts such as described in U.S. Patent 2,484,301. In the method known from this document, a binding agent which evenly penetrates the fiber mixture is used activated in localized places by application of heat and pressure * Both those inside the Felt as well as the fibers lying on the surface are glued together. The surface is pressed As a result, posts no longer have a textile character.

109836/0995

Dipl.-Ing. Η · ίηζ Lewer, patent attorney D - 8 Mönchen 81. Cosimastfafc · 81 ■ Telephone: (0811) 48 38 20

It should also be mentioned that it is known (Swiss patent specification 411 779), on the underside of a felt needled onto a thermoplastic plastic carrier film Thermally weld on plastic sheet. If necessary This plastic web can have punched-outs, whereby the fabric produced becomes gas-permeable. One Structuring of the surface is not intended. Due to the coating with the plastic sheet, the drapability is of the product is significantly reduced. In general, the drapability is enhanced by the coating over the entire area with a carrier layer, even if it is provided with perforations, also reduces the pressure over the entire surface the fabric for the purpose of connecting the fiber layer with the carrier layer has an unfavorable effect on the suppleness of the product, as the binding agent forms a cohesive, stiffening network.

The fiber composite produced by the method according to the invention on the other hand, is characterized by a good textile grip and high flexibility, in that the fibers with Except for those that are on the surface, embedded in the plastic of the carrier, and only in bundles.

The method according to ^M ss of the invention will be explained with reference to the drawing which shows some characteristics of the product sketchy.

It shows

1 shows a diagram of the device for carrying out the method,

109836/0995

Dipl.-Ιης. Η · ίηζ Usmt, patent attorney D - 8 Munich 81. Cosimastrajj «81 ■ Telephone: (0611) 48 38 20

Fig, 2 a-c »partial cross-sections through different embodiments of a piece of equipment, 3 shows a partial cross section through the fiber composite.

On a carrier layer 1 in the form of a sieve-like perforated thermoplastic plastic film web * lrd Fiber fleece 2 with the fiber layer laid across the web and with the help of a needle device 3 from above into the carrier layer 1 needled and solidified at the same time. Due to the needling process, the carrier layer is surrounded by fibers at the top and bottom, whereby the individual fibers cross the plane of the carrier layer several times. The fibers are through the needling process too intertwined in the usual way so that they stick together like felt.

The needle felt web 4 formed in this way now passes through a heating zone S, in which it is heated to at least the softening temperature of the thermoplastic material of the carrier layer 1 will. In the example shown, the heat is generated by means of hot air flowing through it, which is continuously generated by two fans 6.7 is circulated in the direction of the arrow and heated by means of an air heater 8 is supplied. The passage of air through the needle felt web 4 is thanks to the sieve-like openings of the Carrier layer 1 possible, instead of air, steam can also be used as a heat carrier, or the carrier layer can be used 1 are heated by means of high frequency (e.g. capacitive), with the carrier layer 1 advantageously made of PVC (polyvinyl chloride) or PA (polyamide),

10 8 8 3 6/0995

Dipl.-Ing. Heinz Lesser. Patent attorney D - 8 Munich 81. Cosimastrofce 81 Telephone: (0611) 48 38 20

the fibers consist of polyolefins, e.g. PP (polypropylene). The necessary temperature can also be achieved by lingering in a heat canister for a long enough period of time. the Forced heating from the outside by means of thermal radiation or by means of heated calender rolls could, however, because of the poor heat transport through the fiber layer easily lead to damage to the fiber material, especially if a large temperature gradient is generated to accelerate the process. If the plastic of the carrier layer 1 has a relatively low softening range and the fiber layer on one side relatively is thin, it will still be possible to heat up this layer from the surface by means of press rollers without having to use harmful temperatures.

Immediately after leaving the heating zone 5, the needle felt web 4 is gripped by a pair of press rollers 9, 10. At the In the illustrated example, the upper roller 9 has a cylindrical surface profiled with parallel circular rings. the The cylindrical surface of the roller 10 is smooth in this example. Fig. 2 a shows this arrangement in a partial view, the Profiling is achieved by means of conical annular disks 12 which protrude from the roller body 11. The profiling the roller 9 can, however, also be designed differently, e.g. by intersecting ridge-shaped elevations (checked pattern) or also by wart-shaped elevations. Examples of such arrangements are known, e.g. from U.S. Patent 2,464,301 mentioned in the introduction.

109836/0995

Dipl.-Ing. Heinz U $ »* r, Potentanwolt D - 8 Möndien 81, Cosimasttafe · 81 · Telephone: (0811) 48 38 20

ner distance between the annular disks 12 is based on the fiber length matched in a balled state. In one embodiment, this distance was 3.5 mm for a stacked layer of 90 mm of the fibers in the fleece 2. The fiber length can be in vary widely, from about 2 cm to infinity. The width of the flattened pressure surfaces of the washers 12 is on the order of 0.5-1 mm, see above that the surface pressures on the needle felt web 4 are relatively high. Cutting or dislodging the fibers however, through the surveys must be avoided.

3 illustrates the effect of the pressing process when the needle felt web 4 passes through the pair of rollers 9, 10. The fibers 20 located on the upper side of the needle felt web 4 are compressed by the annular disks 12 and bundles thereof are pressed into the carrier layer 1. Since the plastic of the carrier layer is temporarily soft, the fibers are embedded in the plastic and held in place mechanically. In accordance with the degree of softening and the affinity of the base material of the carrier layer 1 with respect to the surface of the fiber material, the fibers are also bonded adhesively. The fibers 20 of the upper side i are advantageously not melted so that they do not flow together to form a coherent, hard layer. On the other hand, on the underside, merging may be desirable in certain applications. In exceptional cases, the underside will also be coated.

The surface pressure and the amount of fibers on the top of the carrier layer 1 are chosen so that the

109836/0995

Dipl.-Ing. Η · ίηζ L «if * r, Pattntanwalt D - 8 Munich 81, Coiimastrafce 81 - Telephone: (0811) 48 38

Fibers 20 lying on the surface are not in the plastic the carrier layer 1 are embedded. ' The fibers that are not pressed into the carrier layer 1 on the surface are held in place by the other fibers as a result of the entanglement caused by the needling process. As a result, the fiber structure of the surface is retained, but the abrasion resistance is still excellent.

If the carrier layer 1 has already softened sufficiently when the needle felt web 4 passes through the pair of rollers 9, 10, no additional heating by the rollers 9, IO is necessary. As a result, the fibers are not exposed to unnecessarily high temperatures. When tests with relatively stiff fibers were carried out with the device described, however, it had been shown that in these cases it was advantageous to heat the roller 9 in order to make the fibers more pliable, e.g. in the case of PP fibers to 140 - 150 degrees C, This prevents the fibers from becoming detached from the embedding in the carrier layer 1 due to their recovery capacity before the plastic of the carrier layer 1 has solidified due to cooling. With suitable materials it is then even possible to soften the carrier layer 1 merely by heating the rollers 9, 10 and to omit the heating by circulating air in the heating zone 5.

The solidification can be accelerated by cooling the roller 10. Instead of the Walae 10, a cooling

109836/0995

OipL-lng. Η ·· "* U * mt, patent attorney D - 8 Mündwi 81. Cosimostrcifc · 81 - Telephone: (0811) 4838

trough are provided that the roller 9 upper part of the circumference and has a stationary or circumferential sliding surface.

Bein AusfOhrungsbeispiel is behind the pair of rollers 9.1O a special cooling zone 13 is arranged, which its cooling effect up to the exit point of the roller pair 9, IO exercises in order to bring about the rapid solidification of the plastic. The cooling, in turn, is based on Air circulation by means of a fan 15, 16. If necessary, the scarce air is cooled by means of an air cooler 14. the Air is either only blown against the surface of the fiber composite material or, as illustrated in FIG. 1, through it driven through this. After cooling, the finished fiber composite is wound up in the form of a web 17 in a winding device 13 to form a roll.

Various additional devices 19 can be provided between the cooling zone 13 and the winding device 18, such as an impregnation or loading device for the underside of the fiber composite 17, a roughening device for the top, etc.

For a selection of the thermoplastic material for di Carrier layer 1 is decisive in addition to the la use Skill «characteristics of the softening area decisive, which should be in such a way that the carrier layer is at the same temperature as the product during later use is exposed, not softened and Min «loses firmness ·, but not too high, so that the temperature

1Q9836 / Ö99S

Dipl.-lnq. H * inz Uhw, patent attorney 0-8 Munich 81. Cosimastrag81 Telephone: (0611) 483820

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In the warming zone 5 the selection does not have to be too high because of the protection of the fiber material · With high-pressure polyethylene (HD-PE) sufficient softening is achieved at around 90 -HO degrees C, which is very favorable in every respect is · This material also has the advantage of being relatively cheap «Show a similarly situated softening range also the copolymers of ethylene with vinyl acetate (EVA) result in a carrier layer with very high toughness »A high strength is also obtained by using a double-layer network, in which the lower layer is made of a tough, not necessarily thermoplastic material and the top layer consist of a thermoplastic plastic which softens at a suitable temperature. That The material of the underlayer can also be selected in view of other desirable properties such as good dimensional stability, bulk, low price, etc.

Various fiber materials are available for forming the fiber fleece 2. All natural materials are suitable or artificial fibers that are not damaged by the temperatures occurring in the heating zone 5 Synthetic fibers are preferably used as staple fibers, however, they can also be used as continuous threads in a loop holder suitable for the needling process. to It is also important to note whether the mechanical bonds are brought about on the one hand by the needling process and on the other by embedding in the carrier layer 1, or whether the fibers are still adhesively bound in the carrier layer 1 should be. The latter case are with the plastic

109836/0995

Dipl.-Ing. Heini Us «* r. Patent attorney D 8 MünaSen 81, Cosimostrafee 81 Telephone: (0811) 48 38

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to choose compatible fibers of the carrier layer. Among the synthetic fibers can be polypropylene (PP) fibers, which soften at temperatures around 140 - 160 degrees C, and polyamide (PA) fibers, which, depending on the type, only soften at higher temperatures of approx. 170 - 220 degrees.

Further examples are the polyacrylic fibers and the polyester fibers. The list was still in place expand at will.

When choosing the fiber material, fiber shrinkage also plays a role. This can be used to achieve special Effects are exploited. The shrinkage can be determined by a suitable choice of the temperature in the heating zone 5 affect. The control is the easier the further the softening areas of the plastics of the fiber material and the carrier layer 1 are apart. In the case of process management with low shrinkage, the fibers are packed relatively loosely in the raised parts of the relief pattern, so that a good cushioning effect is achieved. When the process is carried out with a high shrinkage effect on the fibers, the fibers are packed harder in the elevations and the fiber composite is even better consolidated.

A higher flexibility of the fiber composite is achieved if the annular disks 12 of the roller 9 engage in corresponding depressions 30 of the counter-roller 10, so that the carrier layer 1 is deformed slightly undulating

109836/0995

Dipl.-Ing. Heinz Lesser. Patent attorney D - 8 Munich 81, Cosimastrafee 81 Telephone: (06Π) 48 38

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will. Fig. 2c shows such an arrangement »The deformation the carrier layer 1 can be stretched until the carrier layer is permanently stretched, as in the known deep-drawing of metals, go.

As described, the carrier layer 1 consists of a sieve-like perforated film web. The openings are in Fig. 3 indicated. They can be obtained by punching out or by pulling apart incisions, or the film can have a network structure. In the case of net-like plastic films, however, it is advantageous if the nodes do not protrude from the level of the webs, i.e. are not thickened. An overview of the manufacturing methods such lattice and net films is in the essay by W. Lüers, Processes and Devices for Production of nets made of plastic, magazine Gummi-Asbest-Kunststoffe, 4-6 / 1969, included (examples V and Y in Fig. 1). Sieve-like films of the first type are described in the work of Kroma, Textilverbundstoffe, 19 63, pp. 205-209. the Binding points of the needle film with the carrier layer 1 thus arise on the one hand and through the needle process the embedding of individual fiber bundles in the softened carrier layer. The use of a plastic film with sieve-like openings brings several advantages. The foil is not shredded by the needle punctures, like this is the case with full-surface foils because the needles slide on the webs. She educates at the same Plastic weight per unit area thicker cross-sections for embedding the fiber bundles and it in turn has

1 09836/0995

Dipl.-Ing. Heinz Lesser. Patent attorney D - 8 Munich 81, Cosimastrafee 81 Telephone: (0811) 48 38

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With the same weight per unit area, higher tensile strength, but at the same time lower flexural and torsional stiffness than the full-surface film.

By pressing, the top of the fiber composite is structured in a relief-like manner. This structuring will mainly determined by the profiling of the roller 9, in the second place also by that of the roller 10. One The orientation of the fibers in the non-woven fabric also has an influence. When the fibers are oriented parallel to the profile the roller 9 has poor fiber bonding. With the fibers in the fleece 2 in a transverse position, as shown in FIG. 3 (the web direction is indicated by arrow 21, the fiber direction by arrow 22) the structuring of the surface is less pronounced, but the fiber bond and thus the abrasion resistance of the product are significantly better because the individual Fibers are more often bound in the carrier layer 1. Different combinations are of course possible, e.g. Fleece deposit in several intersecting layers, i.e. alternating one layer with fibers mainly in the Oriented lengthways, another layer with fiber orientation perpendicular to the web, etc. The filing with fiber direction criss-cross diagonal has been used for the generation of checked patterns with profiling parallel and perpendicular to the Orientation proved to be favorable. Since the material is not pressed over the entire surface, but only in a pattern and the fiber bundles are only stapled at the intersections of the printing lines with the webs of the lattice film, the Very fluffy surface.

109836/0995

Dipl.-Ing. Heinz Usjer. Potentanwalt D - 8 Munich 81. Cosimastrajje 31 Telephone (08Π) 48 38

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As a result of the good drapability, the products produced by the process described are suitable not only for floor and wall coverings, but also for furniture cover materials, jacket materials, shoe linings, Slippers, decorative fabrics, curtains. The latter can be made from plastics that are not colored or only very weakly colored be made so that they are well translucent »products with a subsequently roughened surface can be used for other applications, e.g. for ceilings.

Preferably in the case of a corrugated design of the fiber composite, an additional one can be placed on the underside A smooth layer, e.g. a bonded fiber fleece or a foam layer, can be glued on. It arises from it a particularly soft floor covering. When this shift is provided with an area enlargement slot before application, then these are products also drapable and usable accordingly.

In highly extensible backing layer of the product within certain limits is suitable for deep drawing, so that it in this way, Z ₄ as to the covers of the tunnel passages, dashboards in automobiles, etc., can be further processed.

109836/0995

Dipl.-Ing. Mr Leuer. Patent attorney D - 8 Mundien 81. Cosimastrafje 81 Telephone: (0611) 48 38

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Embodiments

Example It for further processing into flooring material certain fiber composite.

Two film webs made of PE with sieve-like openings of 0.5 mm thickness, 50-60% opening area and 170 g / m2 weight per unit area were placed on top of one another and a nonwoven fabric of 250 g / m2 made of 20 denier polyamide fibers, 100 mm staple length with fiber orientation transverse to the longitudinal direction of the The panel is laid down and needled as described. The ^M "was TERIAL at 120 - pressed by 2a profiled roller pair with a distance of 3.5 mm disc 130 degrees C in a and then cooled.. The fiber composite had a weight per unit area of 590 g / m2 and a thickness of approx. 3.5 mm. For the purpose of further processing into flooring material, the underside of the fiber composite was provided with a hotmelt adhesive layer of 400 g / m2 and a further sub-layer of foam or needle composite material of 150 g / m2. The total weight of a floor covering material produced in this way with a thickness of 5.5 mm was 1300 g / m2.

Example 2 »Clothing fabric.

A lattice ölienbahn i of 170 g / m2 according to Example 1

1 09836/0995

Dipl.-Inq. Heinz Usser. Patent attorney D - 8 Munich 81, Cosimastrafje 81 Telephone: (0811) 48 38

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a fiber fleece of 150 g / m2, also in transverse orientation, made of polyamide fibers 8 denier / 60 mm staple length, deposited and needled as described. Pressing at 120 - 130 degrees C with a pair of rollers profiled according to Fig. 2c, distance between the discs 4.5 mm. Cooling. The one obtained in this way Fiber composite had a weight of 320 g / m2 and a thickness of 2.5 mm.

Example 3: Decoration fabric

A fiber fleece of 100 g / m2 made of 8 denier / 60 mm polyamide fibers was placed on a 50 g / m2 PE lattice film web Stacked length and otherwise proceed as in Example 2. The fiber composite had a weight per unit area of 150 q / m2 a thickness of 1.5 mm.

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Claims (13)

Dipl.-Ing. Heinz Lesser. Patent attorney D-S Munich 81. Cosimastrafce 81 - Telephone: (0811) 483820 - 17 - PATENT CLAIMS 1 »Process for the production of a relief-like structured fiber composite with a fiber fleece on a web-shaped, sieve-like openings having or slotted carrier made of a thermoplastic material, needled through it and the needled sheet-like structure is heated for further consolidation at least until the web-shaped carrier has softened is, characterized in that the needled sheet, while the bahnförraige Carrier is still in the softened state, so between two tool surfaces, of which at least has a wart-shaped or ridge-shaped elevation, compressed that the fibers not located in the area of the openings or slits of the carrier are included Except for those that are on the surface of the sheet, in bundles in the plastic of the carrier embedded, after which heat is extracted from the fiber composite so that the softened carrier solidifies again, before the fibers embedded in it under pressure are released from the carrier as a result of their recovery capacity can dissolve 2. The method according to claim 1, characterized in that a screen film made of a thermoplastic material is used as the carrier in the form of a web 109836/0995 Dipl.-Ing. Η · ίηζ Lesjer, patent attorney 0-8 Munich 81. Cosimastrafe · 81 ■ Telephone: (0611) 483820 - 18 - with a softening range of 90 - 120 degrees C and a thermoplastic fiber material for the fiber fleece Plastic with a different softening area above the first is used. 3, method according to claim 2, characterized in, that the needled sheet-like structure on an area between the softening area of the screen film and the temperature lying in the softening range of the fiber material is heated. 4, method according to claim 3, characterized that the parts of the fiber material lying above the web-shaped carrier up to the beginning of softening of the fiber material are heated. 5, method according to claim 1, characterized in, that the needled fabric is heated with the aid of a flowing through the fabric hot medium takes place. 6, method according to claim 4, characterized in, that the warming of the over the railroad Supported parts of the fiber material are carried out by heating the tool surfaces acting from above. 7, method according to claim 1, characterized in, that the heat is extracted with the aid of a cold medium flowing through the fiber composite. 109836/0995 Dipl.-Ing. Heinz Leuef. Patent attorney D - 8 Munich 81. Cosimastra & e 81 - Telephone: (0811) 48 38 8. The method according to claim 1, characterized that the heat is extracted with the help of the tool surface, which acts from below and is cooled for this purpose he follows. 9. The method according to claim 1, characterized in that that the needled and heated flat structure between two counter-rotating and is pressed together with pressure rollers pressed against one another. 10. The method of claim l _{r t} characterized in that the main direction of the fibers in the fiber web transversely to the ridge-shaped elevations of the tool surface, 11. The method according to claim 1, characterized that the fiber composite is additionally provided with an insulating layer on the underside will. 12. The method according to claim 11, characterized in that the additional insulation layer consists of a foam sheet provided with slits allowing an increase in surface area. 13. The method according to claim 1, characterized in that the under the railway 109836/0995 Dipl.-Ing. Heinz less «, patent attorney D - 8 Mönchen 81, Cosimastrafee 81 ■ Telephone: (0811) 48 38 - 20 - Förralgen carrier lying parts of the fiber material when compressing the needled and heated fabric by heating the one acting from below Tool surface to a temperature above the melting temperature of the fiber material at least partially are fused together. 109836/0995