DE20006635U1 - Textile substrate - Google Patents

Description

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Textile substrate

The invention relates - according to the preamble of independent claim 1 - to a textile substrate which has water-draining properties and comprises wool and at least one other fiber. Such substrates are characterized by their excellent ability to absorb and drain water vapor and water. They are particularly suitable for seat covers, in particular covers for seats that are used for long periods without interruption, such as in cars and buses, on trains and airplanes, as well as for office chairs, wheelchairs, etc. The good moisture drainage from the fabric surface helps to ensure good seating comfort, because the seat cover does not feel damp even after sitting for a long time, but always feels dry, thus guaranteeing "air-conditioned seating."

EP 356 708, EP 455 848 and EP 685 583 respectively disclose generic textile substrates which always contain a proportion of natural fibres, in particular wool and ramie.

This proportion of natural fibres is between 65 and 85% by weight of wool and ramie (EP 356 708), it is at least 40% by weight of wool and at least 5% by weight of ramie (EP 455 848) or it comprises at least 40% by weight of wool and at least 15% by weight of ramie, but always more than 85% by weight of both together (EP 685 583).

While EP 356 708 and EP 455 848 always require a proportion of synthetic fibres - be it for the purpose of water drainage or better dyeability - EP 585 583 discloses a textile substrate for seat covers, a woven, knitted or crocheted fabric which has a mixed yarn of 80% by weight wool and 20% by weight ramie in the warp and ramie threads in the weft.

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Initially, it seemed extremely doubtful whether a large or even total omission of synthetic fibers would not limit the design options of the fabric designer too much and, above all, impair the excellent properties of known textiles in terms of water absorption and drainage. The first problem is less serious and can be avoided by using appropriately adapted colors. For a long time, however, it seemed essential to provide a relatively high proportion - at least 15% by weight - of synthetic fibers, preferably polyester, for liquid transport, since their hydrophobic properties were considered responsible for liquid transport over long distances. Surprisingly, however, it was shown that the same function is performed by ramie fiber if it is present in the substrate in sufficient concentration - at least 15% by weight. This was not to be expected due to its chemical composition - degummed ramie consists essentially of cellulose. The fact that ramie is able to transport water over long distances is attributed to a strong capillary effect, which is based on the fact that the ramie fibers form tubes that are also provided with longitudinal grooves on the inside. Consequently, the requirement arose for a content of at least 15% by weight of ramie in a textile substrate, which should meet the high requirements for moisture removal from the fabric surface and guarantee good seating comfort.

Surprisingly, it has now been shown that - if the ramie fibers are omitted and replaced by viscose fibers - a practically equivalent moisture removal from the fabric surface can still be maintained.

These textiles according to the invention consist at least largely, but preferably exclusively, of natural fibres and can therefore be disposed of in a very environmentally friendly manner.

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The textiles according to the invention can be shredded, then piled up and stored at sufficiently high humidity and temperature; they rot completely and are thus actually compostable.

In any case, the discovery of the fact that viscose fibers drain water over long distances forms the basis for a surprisingly simple solution to the problem of providing an alternative textile substrate for seat covers that is not only extremely comfortable in that it always feels dry even during long-term, uninterrupted use under difficult conditions such as high temperatures and high humidity, but also has very little impact on the environment, is particularly easy to dispose of and decomposes under suitable conditions with at most minimal residues requiring disposal. This problem is solved by the features of independent claim 1. Preferred developments of the textile substrate according to the invention arise from the dependent claims.

The textile substrate can also be designed in various ways, as a woven or knitted fabric, in particular as Raschel, Malimo or velour. Such exemplary designs are shown schematically in the figures. They show, with the weft direction running horizontally in each case,

Fig. 1 a fabric,

Fig. 2 a shot rustle, and
Fig. 3 Malimo.

The substrate according to the invention consists of at least 40% by weight of wool and at least 30% by weight of viscose, with the sum of the proportions of wool and viscose amounting to more than 80% by weight. Furthermore, the substrate according to the invention preferably consists exclusively of materials that rot or are at least toxicologically and ecotoxicologically harmless.

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are so that it is compostable without restriction. Even under these conditions it can be equipped to meet a wide variety of requirements. For example, to prevent static charging it can contain less than 5% by weight of metal fibers or wire. If these metal threads are selected accordingly, they oxidize under suitable conditions and rot together with the other components. The use of elastic fibers is also entirely possible, since their proportion can be kept very low - less than 5% by weight - if they do not rot, such as Lycra® (registered trademark of Du Pont de Nemours), or otherwise rotting material such as natural rubber can be used. Elastic fibers can, for example, be incorporated into the substrate by making individual threads entirely of this type of material or by twisting elastic fibers around a yarn consisting essentially of viscose, for example in the weft of a fabric.

Although synthetic fibers such as polyester, polypropylene, polyamide, polyacrylic or aramid are not particularly disruptive in small amounts, they are preferably avoided in the interest of unrestricted compostability, so that all fibers used - apart from any metal fibers - are of animal or plant origin. In addition to wool, viscose is particularly suitable, which is obtained from beech wood and which has preferably been mixed with a flame-retardant agent using an environmentally friendly process. Fibers obtained from other plants are also suitable instead of the corresponding viscose.

It is very advantageous if the substrate comprises a mixed yarn with wool and viscose, preferably one that consists of approximately 30-70% wool and 30-70% viscose by weight. If it is a fabric, the warp or weft can consist of such a mixed yarn, while the weft or warp can consist of another material, e.g. pure viscose.

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or contain parts of other materials. For these and other substrates, it has proven possible and even advantageous to use only wool and viscose and to dispense with other admixtures altogether, unless they are necessary due to special requirements.

Thus, Figure 1 shows a fabric according to the invention, according to a first embodiment, the warp 1 of which is formed from a mixed yarn with 60% by weight wool and 40% by weight viscose, while the weft 2 consists of viscose threads. A corresponding fabric is particularly preferred whose weft consists alternately of a mixed yarn with 60% by weight wool and 40% by weight viscose and of a pure viscose yarn. Overall, this results in a wool content of about 50% by weight and a viscose content of about 50% by weight. Of course, other compositions are also possible, as described above. Thus, in a textile substrate according to the invention, or fabric according to a second embodiment, the weft 2 can be formed from a mixed yarn with 30-70% by weight wool and 30-70% by weight viscose, while the warp 1 consists of viscose threads 2.

A corresponding fabric is then particularly preferred, the warp 1 of which consists alternately of a mixed yarn with 30-70% by weight wool and 30-70% by weight viscose and of a pure viscose yarn. In particularly preferred cases of such an alternation of mixed yarn and pure viscose yarn - be it in the weft 2, according to the first embodiment, or in the warp 1, according to the second embodiment - the ratio ranges from 1:1 to 4:1, i.e. 1 to 4 mixed yarns are preferably used per pure viscose yarn. Suitable viscose fibers are sold, for example, under the name "Redesigned Viscose FR" by the company Lenzing AG, in A-4860 Lenzing, Austria.

In fact, the following absorbencies were measured for two different fabrics, each made of about 50% wool and viscose by the rise height method according to DIN 53924, as is typical for substrates with good water-draining properties:

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Tissue 1 3 hours Tissue 2 3 hours 1 hour > 25.0cm 1 hour > 25.0cm Chain 17.0cm 18.1cm 17.9cm 17.9cm shot 13.6cm 13.5cm

On the one hand, fire regulations are becoming increasingly strict for public buildings such as theaters, schools or sports stadiums, but also for hotels, restaurants and offices, and even for private homes. Particularly strict standards also apply in airplanes, ships and other transport facilities. On the other hand, there are increasing demands that flame-retardant products must also be produced and disposed of in an environmentally friendly manner. Because flame-retardant products are usually in conflict with environmental compatibility, the "lesser evil" is all too often chosen and one-sidedly insists on protection against fire.

Because the textile substrate according to the invention now makes it possible to use viscose as a full replacement for ramie in combination with wool, a further advantage arises from the fact that it has been possible to impregnate the viscose fibers with a flame-retardant agent in an environmentally friendly manner, thus creating a textile substrate that is free of substances that could harm the environment. The compost obtained from the textile substrates according to the invention can therefore be used safely, for example in the garden, even if the textiles previously used were flame-retardant.

For the first time, it has been possible to create a textile substrate for seat covers which:

• is extremely comfortable, staying dry even during long periods of continuous use in difficult conditions such as high temperatures and high humidity;

• has such good flame retardancy that it meets fire safety regulations for seat covers worldwide;

• the environment is not affected in terms of toxicity and ecotoxicity either by production or disposal.

The textiles impregnated with a flame retardant meet all the relevant safety requirements of the automobile, aviation and transport industries and the respective legislative states. There is nothing to stop the substrates according to the invention being used as seat covers, interior linings in public buildings, automobiles, airplanes and trains, etc., but also other equipment and decorative items for public, commercial or private use. In addition, experts are increasingly coming to the conclusion that a better seating climate in automobiles can improve road safety.

Figures 2 and 3 show other typical substrates, Figure 2 Schussraschel and Figure 3 Malimo, which can also be composed in one of the ways described above.

Claims (8)

1. Textile substrate which has water-draining properties and comprises wool and at least viscose fibres, characterized in that - that the warp ( 1 ) or the weft ( 2 ) comprises a blended yarn of 30-70 wt.% wool and 30-70 wt.% viscose and - that the weft ( 2 ) or the warp ( 1 ) alternately comprises a mixed yarn of 30-70 wt.% wool and 30-70 wt.% viscose or a yarn of 100 wt.% viscose. 2. Textile substrate according to claim 1, characterized in - that the warp ( 1 ) or the weft ( 2 ) comprises a blended yarn of 60 wt.% wool and 40 wt.% viscose and - that the weft ( 2 ) or the warp ( 1 ) alternately comprises a mixed yarn of 60 wt. % wool and 40 wt. % viscose or a yarn of 100 wt. % viscose. 3. Textile substrate according to claim 1 or 2, characterized in that the weft ( 2 ) or the warp ( 1 ) alternately comprises a mixed yarn or a pure viscose yarn in a ratio of 1:1 to 4:1. 4. Textile substrate according to one of the preceding claims, characterized in that it comprises 40-70 wt.% wool and 30-60 wt.% viscose. 5. Textile substrate according to one of the preceding claims, characterized in that it comprises a velour, woven fabric, warp or knit fabric, in particular Raschel or Malimo. 6. Textile substrate according to one of the preceding claims, characterized in that it contains less than 5 wt.% elastic fibers and/or metal and/or synthetic fibers. 7. Textile substrate according to one of the preceding claims, characterized in that the viscose fibers are impregnated with a flame retardant agent. 8. Textile substrate according to one of the preceding claims, characterized in that it consists exclusively of materials which decompose under environmental conditions at sufficiently high humidity and temperature or which are toxicologically and ecotoxicologically harmless.