WO2019141628A1 - Dilour carpet having improved use-value properties - Google Patents

Abstract

The present invention relates to a needle-punched dilour carpet, in particular for use in the automobile industry, which has a more wear-resistance surface and advantageous properties compared to conventional carpets for motor vehicle interiors and luggage compartments.

Description

 Dilour carpet with increased utility value properties

The present invention relates to a needled non-woven dilour carpet, especially for use in the automotive industry, with a more wear-resistant surface, which has advantageous properties over conventional carpets for the motor vehicle interior and luggage compartment.

The increase in the utility value properties, in particular the abrasion behavior after the deformation of the carpet to the corresponding component (including floor covering, floor mat, luggage compartment side trim and loading floor of a motor vehicle) are in the foreground during development.

The wear behavior of carpets, in particular of carpets deformed into a component, is determined by a large number of influencing variables.

The following table gives an overview.

Bei den auf dem Markt befindlichen Kraftfahrzeugen findet man verschiedene Ausprägungen von Teppichböden, insbesondere Tufting-, Di- lour- und Flachnadelvlies-Teppiche, vor. Bei Tufting-Teppichen wird insbesondere PA6.6, PA6, PP, rPA und PET sowie rPET sowie die bio-basie- renden Polyamide (PA 5.10; PA 6.10); und bei den Dilour- und Flachnadelvlies-Teppichen PET, PET/PP, PP, PA/PET und rPET vorwiegend eingesetzt.

The motor vehicles on the market have different types of carpets, in particular tufted, dilloured and flat needlepunched carpets. For tufted carpets in particular PA6.6, PA6, PP, rPA and PET as well as rPET and the bio-based polyamides (PA 5.10, PA 6.10); and mainly used in the dilour and flat needle fleece carpets PET, PET / PP, PP, PA / PET and rPET.

In the prior art, processes for the production of Dilour (Velours) carpets are known, see, inter alia, DE 44 09 771 A1, DE 29 00 935 C2 and DE 10 2008 026 968 AI.

In the application of these carpets, especially in the passenger compartment in the floor covering and in the luggage compartment at the loading floor and the side paneling, the wear behavior is in focus.

Here, the wear resistance in the "Taber test" (abrasion resistance) is of particular importance.The surface (color change according to gray scale, texture of the fibrous web) and the weight loss on different tours are evaluated.

In the production of a flat needle punched nonwoven staple fibers are solidified after a web formation by means of carding and crosslapper by multiple needling between two metal plates. In a further step, by means of re-needling in a brush belt, a Dilournadelvlies can be generated from this flat needle felt. In both variants, it is necessary for a good final strength to integrate the staple fibers after needling, thermally or chemically. A Dilour carpet differs from a needle-punched carpet by a higher-quality look and feel, as well as an improved wear behavior.

The integration of the fibers takes place by means of foamed latex or acrylate as well as PE. As further coating materials in the composite PE or an EVA / PE mixture find application. When integrating by means of PE extrusion (directly extruded PE film / layer), the fibers are melted, thus creating a "rigid" entangled pole / fiber underside.Also, the bonding material (PE) can only partly penetrate partially into the fiber composite Deformation of the carpet can lead to breakage of the "rigid" entangled fiber underside, and thus the wear behavior and of course the appearance are drastically deteriorated. The floor covering, the luggage compartment lining are therefore unusable.

Furthermore, there is the following disadvantage of fiber integration in Dilour carpet by means of film or extrusion film:

In order to achieve a bond between the PET fibers on the underside of the carpet, it must be practically melted. However, this has the consequence that the fibers in the lower area are not only adhesively bonded, but also "glass-like" melted, which also explains the deterioration of the abrasion values and thus the higher level of wear The individual fiber loses over a short but important distance their good technological properties (elongation, breaking strength, etc.). In case of load, it can lead increasingly to fiber breakage Rigid extrusion film (rigid fixation) tends to "bimetallic" in the molding and results in less dimensional stability under temperature variations and the risk of fiber / filament breakage.

Also, the fused fibers break during deformation to the component; when using the "fiber binding" according to EP 1 598 476 B1.

Furthermore, hot-melt adhesives and thermoplastic dispersions are used.

Specifically in WO 2017/061970 A1, the incorporation of the carpet by means of bicomponent (BiCo) fibers is discussed. Here the optimization of the (BiCo) fiber fixation by the use of special slot nozzles in the drying oven is described.

A combined use of latex and BiCo fiber is also common in practice.

WO 2017/114808 A1 and WO 2017/114807 A1 describe a carpet construction in the range of 100 to 300 g / m ² fiber weight with multilobal fibers and good abrasion resistance. Among others, fibers with a round and trilobal cross-section are used. As inclusion of latex, binder fiber, powder or films are given.

The material used in the manufacture of particular floor coverings for the automotive industry (used fiber mix, fiber fineness, fiber length, grammage, binder, etc.) is listed in the technical delivery specifications of the car manufacturer. In today's market / in the automobile located, deformed to the component Dilour carpets, it is found that the specified in the specifications of the car manufacturer "wear values" can not be respected or only margins.

On the one hand, the type of pre-needling of the nonwovens (one-sided, two-sided, different needle density and stitch depth) as well as the fiber mix, the combination of needle types in dilourization and, on the other hand, the manner of fiber incorporation have been tried (see, inter alia, WO 2017 / WO 2005/024122 A1, WO 2010/001043 A1, WO 2012/135909 A1, WO 2016/113488 A1) up to the optimization of the temperature-time behavior (DE 10 2012 101 925 B4 , DE 25 01 366 A1) and the tool gap width in the deformation of the carpets, including sub-layers to meet the requirements of a component.

However, when testing the wear behavior by means of the TABER test, fiber shearing off is often the cause.

In WO 2017/114808 A1 and WO 2017/114807 A1, reference is made to the fiber-cross-sectional structure in the fiber mix as well as in the layer composite.

The mentioned types of connection are state of the art; The fiber cross-section structures are also found in the prior art (WO 2013/171099 A1, WO 00/12789 A1, WO 01/90452 A1). A consideration of the interplay between material, processing aids, fiber structure, needling parameters and incorporation is not set forth in the prior art, especially with regard to increasing the utility properties of the carpet or the deformed carpet to the component.

The object of the invention is therefore to provide a Dilour carpet, including the method for producing the Dilour carpet - starting from the fiber via the needling to the integration of the fibers - especially for the automotive market, the current after deformation to the component specified (wear) requirement of car manufacturers.

In a first embodiment of the invention, the aforementioned object of the present invention is achieved by a shorn Dilour carpet of PET fibers having a final fiber weight in the range of 300 to 800 g / m ² , optionally 5 to 25 wt .-% bicomponent fibers contain, where

the denier of the PET fibers is in a range of 3.3 to 22 dtex, the fiber length of the PET fibers is between 45 and 90 mm, and the fiber height of the PET fibers over ground (pile height / pile layer thickness) is 2.5 to 6 mm is,

characterized in that

the PET fibers are superficially applied with a spin finish of 0.2 to 0.7 wt .-% based on the fiber weight;

the fiber crimp of the PET fibers is between 2 and 7 crimps per centimeter;

the fiber crystallinity of the PET fibers is 25% to 40%; the Dilour needling of the PET fibers of the carpet is done with fork / crown or fork / fork needles;

the PET fibers of the carpet emerge perpendicular to the fiber ground and the PET fibers of the carpet are incorporated with EVA or a thermoplastic dispersion or a non-crosslinking acrylate at an application rate of 50 to 160 g / m ² .

Based on the main influencing factors that decisively determine the wear behavior, it has surprisingly been found that, taking into account the above correlations / interactions of the influencing variables, it is possible to achieve a significant improvement in the use properties.

In particular, there is a significant influence on the wear behavior when the following influencing variables are coordinated:

 - spin finish

 - fiber crimping

 - fiber crystallinity

 - Needle type combination

 - Fiber exit angle

 - Integration

Of course, during the deformation of the carpet (including underlayers), the known temperature-time regime and the tool gap dimension determine the wear behavior.

In particular, the interaction / mutual influence of: ♦ Task of spin finish

 Improvement of the spinning ability (antistatic equipment - prevention of electrostatic charging of the fibers, process stability, reduction of fiber breaks ...)

 Reduction of the coefficient of static friction and sliding friction of the filament surface compared to friction partners. When designing the preparation, it should be noted that needling and incorporation are not adversely affected.

 Tuning of the finishing and the fiber preparation, which is applied before or after the needling, regarding the surface tension.

If too much spin finish is applied to the fibers, then no compound latex / acrylate can be added to the fiber, so that stable incorporation is not guaranteed.

♦ Influence of fiber crystallinity

 The desired fiber crystallinity should be in the range between 25% to 40%.

- With increasing crystallinity, the stiffness increases and the deformability of the fiber decreases.

At the same time, the moisture absorption capacity and the improved deformation behavior mediated by the water decrease. - Too low crystallinity leads to the formation of Nahordnungs- structures in the amorphous phase, even below the glass transition temperature, which in turn leads to embrittlement.

- Crystallinity must preferably be realized by Fibrillenkristalle (high orientation) to prevent the brittleness of a lamellar microstructure.

 - Stabilization of the crystalline structure and shrinkage degradation for thermal calming by tempering after filament production.

♦ fiber incorporation

 - Fiber preparation and incorporation must be coordinated with one another in order to achieve optimal wetting of the fiber and thus optimal fixation of the fiber in the integration. Due to a lack of wetting of the fiber through the integration, the fibers can be pulled out of the integration in case of loading.

 In particular, the incorporation should be thermoplastic in order to facilitate geometric deformation by plastic deformation in the thermoforming process and to minimize the build-up of stresses which can lead to voids and so on.

 The viscosity of the material of the binding should be high enough to avoid sinking / draining into deeper nonwoven layers during thermoforming.

- The temperature of the glass transition of the integration should be well below that of the fiber, so that in the case of deformation, the fiber does not break off at the exit point from the stiff integration. Better is the participation of the integration with the fiber by elastic / plastic deformation with subsequent partial recovery.

 - In order to achieve sufficient rigidity of the integration, it should have a certain crystallinity and may be filled with mineral fillers (chalk, talc) and reinforced. The melting and crystallization behavior must fit the thermoforming process, so that the heat input is sufficient to realize the plastic deformation and sufficient rigidity is realized in the cooling phase, so that the component is geometrically stable enough for demolding.

Excessive crosslinking of the latex causes the latex structure to break and thus a poor incorporation is found. The fibers can not move in the latex structure (when deformed) and break fibers.

Embodiment 1

A sheared 540 g / m ² (fiber end weight) PET carpet was produced.

Care was taken during fiber production to ensure that the "bottle flakes" used were well sorted and free of contaminants / contaminants.As a spin finish, a fatty acid polyglycol ester with an antistatic component was used, at 0.5% by weight. The fiber finenesses of the fibers used were 20% by weight 6.7 dtex and 80% by weight 13 dtex; the crystallinity of the fibers was between 35 and 37%; and the crimp was between 2 and 4 crimps per cm. The fiber length was 65mm. The pre-needling was done with 120 E / cm ² and the dilourization with 680 E / m ² when using fork / fork needles. The fiber exit angle was perpendicular to the fiber bottom.

The integration of the fibers was done by means of padder. 100 g / m ² commercial non-crosslinking acrylate was applied.

The carpet was sheared to 4mm fiber height above ground (pile height / pile thickness).

The test of the carpet roll goods by means of Taber Abraser (H18, 1000g) showed at 2000 tours a very good surface quality that was completely in the specification of the car manufacturer (there required 1000 tours).

After the deformation of this carpet, it was laminated with 700 g / m ² heavy foil and 154 g / m ² contact fleece (PE / PA / PE + PET) to a floor covering. This showed the abrasion behavior of a surface finish according to a specification at 1600 tours.

Embodiment 2:

A sheared 700g / m ² (fiber end weight) PET carpet was made. In fiber production, care was also taken to ensure that the "bottle flakes" used were well sorted and free of contaminants / contaminants A spinel preparation used was a commercial fatty acid polyglycol ester with an antistatic component, at 0.6% by weight.

The fiber finenesses of the fibers used were 60% by weight 11 dtex, 30% by weight 17 dtex and 10% by weight 4.4 dtex (BiCo fiber); the crystallinity of the 11 and 17 dtex fibers was between 32 and 35%; and the crimp was between 3 and 5 crimps per cm. The fiber length was 60mm for the 11 and 17 dtex fibers and 51mm for the BiCo fiber.

The first pre-needling was carried out with 120 U / cm ² and the second pre-drossing -from the other side- (roll rotated by 180 °) - with 100 U / cm ² ; the dilourization was carried out with 750 E / m ² when using fork / fork needles. The fiber exit angle was perpendicular to the fiber bottom.

The integration of the fibers was done in addition to the BiCo fiber by means of padder; 80 g / m ² commercial non-crosslinking acrylate was applied.

The carpet was sheared to 4mm fiber height above ground (pile height / pile thickness). The examination of the carpet roll goods by means of Taber Abraser (H18, 1000g) showed at 2000 tours a very good surface quality, which was fully in specification of the car manufacturer (there required 1000 tours). The weight loss was 0.23g.

After the deformation of this carpet, 2000 g / m2 heavy foil and 154 g / m2 contact fleece (PE / PA / PE + PET) were laminated to form a floor covering. This showed the abrasion behavior of a surface finish according to a specification at 1500 tours.

The weight loss was 0.35g.

Claims

claims: 1. Peeled Dilour carpet of PET fibers having a final fiber weight in the range of 300 to 800 g / m ² , optionally containing 5 to 25 wt .-% bicomponent fibers, wherein the denier of the PET fibers is in a range of 3.3 to 22 dtex, the fiber length of the PET fibers is between 45 and 90 mm, and the fiber height of the PET fibers over ground (pile height / pile layer thickness) is 2.5 to 6 mm is, characterized in that the PET fibers are superficially applied with a spin finish of 0.2 to 0.7 wt .-% based on the fiber weight; the fiber crimp of the PET fibers is between 2 and 7 crimps per centimeter; the fiber crystallinity of the PET fibers is 25% to 40%; the Dilour needling of the PET fibers of the carpet is done with fork / crown or fork / fork needles; the PET fibers of the carpet emerge perpendicular to the fiber ground and the PET fibers of the carpet are incorporated with EVA or a thermoplastic dispersion or a non-crosslinking acrylate at an application rate of 50 to 160 g / m ² . 2. Dilour carpet according to claim 1, characterized in that the PET fibers have a round, trilobal or quadrilobal fiber cross-section. 3. Dilour carpet according to claim 1 or 2, characterized in that the PET fibers comprise hollow fibers or hollow fibers. 4. Dilour carpet according to one of claims 1 to 3, characterized in that it is (acoustically) flow-open.