DE29617779U1 - Water vapor permeable and water-repellent lining material for the clothing and shoe industry - Google Patents

Description

G96

Description

Peter Wirz 53721 Siegburg

Water vapor permeable and water repellent lining material for the clothing and shoe industry

The innovation concerns a water vapor-permeable and water-repellent lining material for the clothing and shoe industry made of a layer of a knitted textile fabric and a layer of a meltblown fleece made of meltblown microfibers made of thermoplastic material.

Water vapor permeable and water-repellent lining materials for the clothing and shoe industry are widely known and are being used in ever-increasing numbers in clothing and shoes to make them water-repellent and water vapor permeable, also often referred to as breathable. In contrast to waterproof materials, for this water-repellent, i.e. hydrophobic finish of the respective clothing items, the lining material has fabric pores that are not closed, so the lining material remains water vapor permeable, i.e. breathable, while these fabric pores are too small for water drops to pass through due to the surface tensions prevailing in them.

For example, textiles and shoes that contain such a water-repellent and breathable interlining based on polytetrafluoroethylene (PTFE) fibers as a membrane have been on the market for some time. 5

The disadvantage of the known water-repellent and water vapor-permeable interlinings is, however, that they require complex and therefore costly production, and that they have only low mechanical strength and appear to be in need of improvement in terms of tear and abrasion resistance.

The aim of the innovation is therefore to propose a water vapor-permeable and water-repellent lining material for the clothing and shoe industry, which can be produced efficiently and at low cost with reduced effort.

This task is solved with an innovative water vapor permeable and water repellent lining material for the clothing and shoe industry according to the features of claim 1.

Advantageous embodiments of the innovation can be found in the subclaims.

The innovation proposes a water vapor permeable and water repellent intermediate lining for the clothing and shoe industry, in which a layer of a meltblown fleece made of meltblown microfibers with a basis weight of 10 to 100 g/m ² , preferably 20 to 70 g/m ² , and a knitted textile fabric are connected by heat and pressure treatment, in particular are laminated, wherein the meltblown fleece is compacted by plasticization to form a film-like layer, the residual pores of which have a residual pore size that enables water vapor permeability but repels water passage.

The composite for the new lining material can be easily produced from an inexpensive knitted textile fabric with larger open fabric pores and good strength and an equally inexpensive meltblown fleece made of meltblown microfibers, which also contains open fabric pores, for example by laminating under the influence of temperature and pressure.

The innovation teaches that the meltblown fleece is melted and compacted into a film-like layer by the heat and pressure treatment during the lamination process, so that on the one hand a strong bond with the textile surface is created, but on the other hand, due to the film-like formation of the meltblown fleece, the residual pores that remain after bonding have a significantly smaller residual pore size than the original pore size in the meltblown fleece. This residual pore size, which is also significantly smaller than the pore size of the knitted textile surface, gives the composite the desired water vapor permeability while simultaneously preventing water from passing through, so that the lining material according to the innovation can be used as a waterproof and breathable layer in the manner of a membrane in clothing and footwear.

In order to give the lining material according to the innovation a pleasant feel and high strength, in particular tear resistance, the innovation proposes that a strong warp knit, such as charmeuse, is used as the knitted textile fabric. Such charmeuse can be made, for example, from polyamide fibers, which have a particularly high abrasion resistance, or can be made in a mixture with other fibers, such as natural fibers and/or man-made fibers, in order to achieve certain desired properties of the charmeuse.

It is advantageous to use hydrophobic thermoplastic fibres such as

for example, made of polypropylene or other suitable plastic fibers made of polyamide or thermoplastic polyester, which may be treated with a hydrophobic agent. The microfibers can be made hydrophobic using a hydrophobic agent during the production of the meltblown fleece, for example by spraying, or the meltblown fleece can be subsequently treated with a hydrophobic agent, for example by spraying the surface with the hydrophobic agent or dipping it into a bath containing the hydrophobic agent.

In the same way, it is also possible to form the knitted textile fabric based on natural fibers, such as cotton or silk and/or chemical fibers, such as artificial silk, for example rayon or viscose, and to use other suitable weaves using the aforementioned fibers instead of charmeuse.

For the production of the meltblown fleece for the composite forming the innovative lining material, it is proposed that this be made from meltblown microfibers based on thermoplastic polyurethane. Such polyurethanes already have water-repellent properties that contribute to the desired waterproofness of the innovative lining material and bond to a knitted textile fabric, such as the charmeuse already mentioned based on polyamide fibers, for example, under pressure and heat without additional adhesion promoters.

In a preferred embodiment of the innovation, it is proposed that the meltblown nonwoven fabric is made of meltblown microfibers from a thermoplastic polyurethane with a melting point range of 90 to 150 ^° C according to DIN 5346 ° and a specific weight of 1.13 to 1.25 g/cm ³ and a tear strength of at least 10 N/mm ² , preferably at least 3 0 N/mm ² , according to DIN 53504.

By selecting such thermoplastic polyurethanes with certain additional properties, the innovative lining material can be adapted to different uses.

According to one embodiment of the innovation, a thermoplastic polyurethane with a relatively high melting point range of 130 to 150 ^° C according to DIN 53460 and a Shore A hardness of at least 75, preferably at least 80, according to DIN 53505 and an elongation in percent of at least 500, preferably 600 according to DIN 53 504 is used to produce the meltblown fleece from meltblown microfibers. Such a meltblown fleece has a high thermal load capacity and a high mechanical strength, so that a lining material produced with this meltblown fleece can be used very well in highly stressed clothing and shoes, for example in sports and work clothing.

In another advantageous embodiment of the innovation, it is proposed to use a largely linear polyester urethane with a melt viscosity index MVI (190°C, 10 kg) of 15 to 23 cm ³ /10 min. and a softening range of 60 to 70 ⁰ C according to Kofier as the thermoplastic polyurethane. A meltblown fleece made from such a polyurethane can be bonded to the textile fabric at lower temperatures to form the lining material according to the innovation, which is particularly advantageous for thermally sensitive textile fabrics and also reduces the energy required for the bonding and enables higher speeds when producing the lining material according to the innovation.

5 In a further embodiment of the innovation, it is proposed that the meltblown fleece of the composite forming the lining material according to the innovation is made of meltblown

To form microfibers based on polytetrafluoroethylene (PTFE) and to compress them into a film-like layer.

It is also possible to form the meltblown fleece from a mixture of meltblown microfibers made of thermoplastics with water vapor-permeable and water-repellent properties, with at least 50% by weight of the microfibers advantageously being made of thermoplastic polyurethane or PTFE. In such a case, the meltblown fleece mixed from fibers of thermoplastics can contain 1 to 50% by weight of meltblown microfibers based on, for example, polypropylene or polyethylene or other suitable thermoplastics.

Meltblown nonwovens without additional consolidation, for example through pattern embossing or calendering, are preferably used. However, embossed and additionally pre-consolidated meltblown nonwovens can also be used for the innovation.

In each of the above-mentioned embodiments, the meltblown fleece, regardless of its raw materials, is melted at least on the surface under pressure and heat during the bonding with the textile fabric, and this melted area is compacted in a film-like manner. The meltblown fleece experiences a greater or lesser reduction in thickness, so that the finished intermediate lining according to the innovation can appear optically like a textile fabric provided with a thin coating.

It is important, however, that the innovative compaction of the meltblown fleece into a film-like layer does not completely close the originally existing open pores, but merely reduces them to a sufficient number of significantly smaller residual pores.

which allow water vapor to pass through the composite, but are too narrow for water droplets to pass through.

A lining material in accordance with the innovation that is easy to process for the clothing and shoe industry advantageously has a textile fabric with a basis weight of 10 g/m to 100 g/m ² .

In order to increase the water-repellent properties of the lining material according to the innovation, it is also possible to provide the lining material with a hydrophobic finish.

The hydrophobic treatment of nonwovens is known per se and is described, for example, in US 3837 996. Suitable hydrophobic agents are, for example, paraffins, waxes, metal soaps, etc. with additives of aluminum or zirconium salts, quaternary organic compounds, urea derivatives, fatty acid-modified melamine resins, chromium complex salts, silicones, organic tin compounds, glutaraldehyde, etc., which are commercially available. Fluorocarbon compounds, in particular perfluorinated hydrocarbons or mixtures of these with other suitable substances, such as lithium nitrate, can also be used advantageously.

The hydrophobic treatment of the composite with such a hydrophobic agent can be carried out by providing either only the meltblown fleece or the textile fabric or the entire lining material made of meltblown fleece and textile fabric with the hydrophobic agent in the desired amount before or after the production of the lining material.

Since the hydrophobic agents mentioned remain porous even after application to the layer to be treated, the breathability of the lining material according to the innovation is not lost even when treated with hydrophobic agents.

The innovative method for producing the previously explained water vapor permeable and water repellent lining material for the clothing and shoe industry from a composite containing a layer of a knitted textile fabric and a layer of a meltblown fleece made of meltblown microfibers made of thermoplastic material is based on the fact that an adhesive bond of the layers is produced by the action of pressure and heat.

According to the innovation, the two layers pass through an elongated gap formed between two rotating conveyor belts and while passing through the gap, a temperature of 90 to 180 ⁰ C and a pressure of 5 to 30 kN/cm act on the layers for at least 10 seconds, whereby the microfibers of the meltblown fleece are melted and compressed into a film-like layer, so that the residual pores of the meltblown fleece compressed into a film-like layer have a residual pore size that repel the passage of water but ensure water vapor permeability.

The strong bond between the meltblown fleece and the knitted textile fabric is achieved without the need for additional adhesives such as glue or the like. At the same time, the pores contained in the film-like compacted meltblown fleece are reduced in size compared to the original pore size to residual pores, which have such a small residual pore size that they repel the passage of water, but at the same time ensure water vapor permeability and thus the desired bond is formed from a textile fabric as a mechanically resilient carrier layer and the film-like compacted meltblown fleece for the breathable and water-repellent intermediate lining.

Since the innovative compaction of the meltblown fleece into a film-like layer at temperatures of 90 to 180 ⁰ C

depending on the meltblown fleece used and the raw material properties that come into play, the properties of the knitted textile fabric still contained in the composite are not influenced or changed, since the fibers used to form the textile fabric do not experience any impairment or change at the temperatures mentioned. The layer of knitted textile fabric contained in the composite therefore primarily serves as a carrier layer for the innovative lining material and gives it the desired strength, while the meltblown fleece compressed into a film-like layer reduces the pore size in the composite and gives the innovative lining material its water-repellent and water vapor-permeable properties.

To increase the water-repellent properties, the meltblown fleece and/or the knitted textile surface can be made hydrophobic with a suitable hydrophobic agent before or after they are combined to form the new lining material.

The innovation is explained in more detail below using an example in the drawing. Show

Fig. la a section through a lining material before the composite is made

0 Fig. Ib the lining material according to Fig. la after the

Establishing the connection

Fig. 2 shows a schematic representation of a device

for producing a lining material. 35

As can be seen from Fig. la and Ib, a water vapor permeable and water repellent lining material for the clothing and shoe industry is made of a composite,

containing a layer of a knitted textile fabric 3, for example a charmeuse based on polyamide fibers and/or natural fibers and a layer of a meltblown fleece 2 made of meltblown microfibers. The meltblown fleece is made, for example, from meltblown microfibers made of a thermoplastic polyurethane with a density of 1.19 g/cm ³ , a melting point range of 130 to 150 ⁰ C, a Shore A hardness of 85, an elongation of 700%, and a tear strength of 4 0 N/mm ² . The microfibers have a diameter of less than 10 μπα.

As can be seen from the comparison of Fig. 1a and 1b, in the finished composite 4 shown in Fig. 1b, the meltblown fleece, which in Fig. 1a is loosely laid as a layer on the pre-composite 4a shown there on the knitted textile fabric 3, is compressed to form a film-like layer 2a, which has been brought about by a heat and pressure treatment during the production of the composite 4, as will be explained in more detail below.

The composite 4 shown in Fig. 1b for forming a lining material for the clothing and shoe industry thus has the knitted textile fabric 3 as a carrier web, which gives the composite 4 the desired strength, with the textile fabric 3 being firmly bonded to the meltblown fleece compacted to form the film-like layer 2a. This film-like layer 2a made of the meltblown fleece has residual pores that are significantly smaller than the original pore size, with this residual pore size enabling the water vapor permeability of the composite 4, but repelling water passage, so that the desired breathable and waterproof lining material for the clothing and shoe industry is created by means of the composite 4.

For example, such a composite 4 produced by means of lamination has a charmeuse as a textile surface 3 with a surface weight of 30 to 100 g

and a compacted polyurethane meltblown fleece with a basis weight of 20 to 60 g/m.

The production of this composite 4 with meltblown fleece compressed into a film-like layer 2a is shown schematically in Fig. 2.

As can be seen from this Fig. 2, a laminating device 1, which is known as a flatbed laminating device, is fed one layer each of a meltblown fleece 2 and a textile fabric 3 from rolls 20 and 30 in the direction of arrow Pl and P2, respectively.

The meltblown fleece 2 can optionally be consolidated by pattern embossing in a known manner.

The laminating device 1 has an elongated gap S through which the layers of the meltblown fleece 2 and the textile fabric 3 are passed for the purpose of bonding them firmly. The elongated gap S is formed between two rotating conveyor belts 10, 11, which are driven in the same direction in a manner not shown in detail and ensure that the layers of meltblown fleece 2 and textile fabric 3 are transported evenly through the gap S.

Furthermore, the laminating device 1 has several heating elements 12 and possibly cooling elements 12a, which act on the layers of meltblown fleece 2 and textile fabric 3 to be connected at the desired temperature. In addition, several pressure rollers 13 are provided inside the laminating device 1, which act on the layers to be connected with the desired pressure, so that when passing through the laminating device 1, the composite 4 of textile fabric 3 and meltblown fleece 2 is produced and can be wound up on a winding roll 40 in the direction of arrow P3.

As a result of the elongated gap S inside the laminating device 1 between the rotating conveyor belts 10, 11, the desired temperature and pressure are applied evenly over a longer period of time, namely as long as the composite needs to pass through the elongated gap S. This requires a uniform effect of the temperatures and pressures, so that the meltblown fleece 2 is evenly melted at least partially starting from its surfaces and is compressed into a film-like layer 2a, which gives the composite 4 the water vapor-permeable and water-repellent properties already described as a result of the small residual pore size in the film-like layer 2a. The results can be optimized by appropriately regulating the temperature and pressure inside the gap S and the speed at which the composite 4 passes through the gap.

The production of the composite and the associated compaction of the meltblown fleece to form the film-like layer 2a takes place, for example, at temperatures of 150 to 170 ^° C and a pressure of 25 kN/cm inside the gap S, whereby, however, the textile fabric 3 of the composite 4 does not experience any impairment or change during the bonding, since the prevailing temperatures are far below the maximum permissible temperature for a textile fabric 3 which is made, for example, from polyamide fibers.

Here, the laminating device 1 according to Fig. 2 is designed so that the gap S between the conveyor belts 10, 11 forms a length of at least 1 m, preferably 2 to 3 m, so that at a transport or pull-through speed of for example 5 m/min, a minimum stay and exposure to pressure and temperature on the layers to be joined together of 10 seconds, preferably 15 seconds or longer is guaranteed.

In order to prevent the meltblown fleece from sticking to the rotating conveyor belts 10, 11 during lamination, these can be provided with a Teflon coating or similar or can be made entirely of this material. 5

In order to support the melting and subsequent compaction of the meltblown fleece into the film-like layer 2a, the meltblown fleece fed to the laminating device 1 can also be melted on the surface immediately before entering the gap S by means of a suitable heating element (not shown in Fig. 2) through the heat radiation emitted by it, so that the subsequent compaction into the film-like layer 2a in the interior of the laminating device 1 is facilitated.

The production of the composite 4 for a water vapor permeable and water repellent lining material for the clothing and shoe industry is thus carried out with little technical effort and the individual layers of the composite can also be produced inexpensively in large quantities, so that an economical production of the innovative water vapor permeable and water repellent lining material is guaranteed.

The new lining material therefore has a significantly increased tear and abrasion resistance compared to the known lining materials due to the use of a knitted textile fabric as a carrier web and can be exposed to greater mechanical stress, for example in sportswear. The use of meltblown fleeces made of thermoplastic synthetic fibers such as TPU with a low basis weight enables such lining materials to be produced inexpensively.

Claims (15)

G 96 Protection claims 1. Water vapor permeable and water repellent lining material for the clothing and shoe industry made of a layer of a knitted textile fabric and a layer of a meltblown fleece made of meltblown microfibers made of thermoplastic, the meltblown fleece having a basis weight of 10 to 100 g/m ² , preferably 20 to 70 g/m ² , and the fabric and the meltblown fleece being bonded by heat and pressure treatment, the meltblown fleece being compacted by plasticization to form a film-like layer with a smooth surface and having residual pores of a residual pore size which enable water vapor permeability but repel water passage. 2. Feed material according to claim 1, characterized in that a stitch-resistant warp knit fabric, such as charmeuse, is used as the knitted textile fabric. 3. Feed material according to claim 2, characterized in that a charmeuse containing polyamide fibers alone or in mixtures with other fibers, such as natural fibers and/or chemical fibers, is provided. 4. Lining material according to one of claims 1 to 2, characterized in that the knitted textile fabric is formed on the basis of natural fibers, such as cotton, silk and/or chemical fibers, such as artificial silk or polyester fibers or polypropylene fibers. 5. Lining material according to one of claims 1 to 4, characterized in that the meltblown fleece is formed from meltblown microfibers based on thermoplastic polyurethane. 6. Feed material according to claim 5, characterized in that the meltblown fleece is made of meltblown microfibers made of a polyurethane with a melting point range of 90 to 150 ^° C according to DIN 53460 and a specific weight of 1.13 to 1.25 g/cm ³ and a tear strength of at least 10 N/mm according to DIN 53504. 7. Lining material according to claim 6, characterized in that the thermoplastic polyurethane has a melting point range of 13 0 to 150 ⁰ C according to DIN 53460 and a Shore A hardness of at least 75, preferably at least 80, according to DIN 53505 and an elongation in % of at least 500, preferably at least 600, according to DIN 53504. 8. Lining material according to claim 6, characterized in that the thermoplastic polyurethane used is a largely linear polyester urethane with a melt viscosity binder MVI (190°C, 10 kg) of up to 23 cm ³ /10 min. and a softening range of 60 to 70 ⁰ C according to Kofier. 0 9. Lining material according to one of claims 1 to 4, characterized in that the meltblown fleece contains meltblown microfibers made of polytetrafluoroethylene (PTFE). 10. Lining material according to one of claims 1 to 9, characterized in that the meltblown fleece consists of a mixture of meltblown microfibers made of thermoplastics with water vapor permeable and water repellent properties, wherein at least 50% by weight of the meltblown microfibers are made of thermoplastic polyurethane or PTFE. 5 11. Feed material according to claim 10, characterized in that the meltblown nonwoven contains meltblown microfibers based on polypropylene or polyethylene.
10 12. Lining material according to one of claims 1 to 11, characterized in that the textile fabric has a basis weight of 10 g/m ² to 100 g/m ² . 13. Lining material according to one of claims 1 to 12, characterized by a composite produced by means of lamination of a charmeuse with a basis weight of 30 to 100 g/m and a polyurethane meltblown fleece with a basis weight of 20 to 60 g/m ² . 14. Lining material according to one of claims 1 to 13, characterized in that the meltblown fleece and/or the knitted textile fabric is hydrophobically treated. 15. Lining material according to one of claims 1 to 13, characterized in that it comprises, as a knitted textile fabric, a charmeuse based on polyamide with a basis weight of 10 to 100 g/m and a hydrophobically treated meltblown fleece made of a thermoplastic polyurethane produced by means of a hydrophobicizing agent.