EP1224355B1 - Use of a fleece as heel lining for use in the shoe industry - Google Patents

Abstract

The invention relates to a heel lining for use in the shoe industry comprising a polymer impregnated non-woven having a surface area weight of 180 to 350 g/m<2> and a tear strength of > 15 N in a longitudinal and a perpendicular direction. The non-woven consists of melt spun, aerodynamically stretched multi-component endless filaments which are arranged directly to form a non-woven. Said non-woven has a titer of < 2 dtex. The multi-component endless filaments are split and hardened when said filaments have attained a pre-defined strength of 90 % of the supermicro-endless filaments, i.e. a titer of < 0.2 dtex.

Description

The invention relates to the use of a nonwoven fabric as heel lining for the shoe industry.

The shoe industry uses particularly abrasion-resistant materials for the Lining the rear part of a shoe, the so-called heel cap, used. On the one hand, these materials are intended to absorb the forces caused by the foot on the shoe, especially when rolling in the longitudinal direction on the other hand, they must be subjected to the frictional forces caused by which at least partially moved up and down when walking in the shoe Be called forth, withstand. To prevent it from slipping out unintentionally Avoiding out of the shoe during the rolling motion is traditionally one rough or suede-like material used as heel lining, which by a frictional connection with the foot or the stocking of the wearer Prevents slipping out of the shoe.

In addition to the heel fodder made from natural materials synthetic materials are also used. From documents DE-A 44 33 078 and DE-A 196 42 253 are lining materials for the shoe industry known, which are made of synthetic fibers. For example these synthetic materials needled nonwovens that pass through dry Carding from polyester, viscose, polyamide, polypropylene fibers or

Mixtures of these fibers are made. To this end, fiber pile with a basis weight of up to 800 g / m ^{2 is} presented and mechanically consolidated by intensive needling. This process step alone is very time-consuming and therefore retatively expensive. This is usually followed by shrinking of the needle-punched nonwoven fabric by hot air or steam, which leads to a densification of the material and a further solidification with regard to the setting of the density desired for the application. In order to achieve the necessary strength parameters such as tearing and tear propagation resistance of the needle-punched nonwoven, it is coated with a heat-coagulable latex binder dispersion such as styrene-butadiene rubber (styrene-butadiene rubber - SBR) or nitrile-butadiene rubber (nitrile-butadiene rubber). NBR) impregnated and then dried. The latex content is approx. 30 to 60% by weight of the impregnated nonwoven weight. The material prepared in this way is split into two to four thinner layers. This splitting process was adopted from the leather industry for nonwovens in order to increase productivity in the production of nonwovens. The fission products can be sanded to make the surface even and to improve the optical finish. Finally, a hot melt adhesive is applied to one of the two sides to simplify further processing. Disadvantages of the synthetic heel lining used up to now are, above all, the very different strength values in the longitudinal and transverse directions, the loss of strength due to the splitting of the fiber bundle arranged vertically from needling, and the unevenness of the individual layers with regard to the insertion and removal side.

Nonwovens with a basis weight of 5 to 600 g / m ^{2 are} known from document US Pat. No. 5,899,785, which consist of continuous composite filaments which can be separated along their longitudinal direction, have a fiber titer of 0.3 to 10 dtex and consist of consist of at least three filaments, which are formed from at least two different polymer materials, each filament having a titer between 0.005 and 2 dtex and the ratio between the cross-sectional area of a filament and the total cross-sectional area of the uniform composite filaments between 0.5 and 90% lies, wherein the composite filaments have a tubular cavity in the direction of their central axis. Such nonwovens should be suitable for the production of intermediate layers of shoes or the production of synthetic leather.

The document "Nouveaux cuirs synthetiques japonais", Industrie Textile, FR, No. 1255/1256, Page 63 describes new synthetic leather, the nonwovens on the The basis of bicomponent microfibers. The fibers consisting of Polyester and polyamide and a fiber titer of 0.5 dtex are used Treatment with water jets in six polyester segments with one titer of 0.05 dtex and split polyamide segments with a titer of 0.1 dtex. After the impregnation with polyurethane, a suede with excellent Properties especially with regard to the insulation ability and Get air permeability.

The object of the invention is to use a heel lining for the shoe industry which, at grammages from 180 to 350 g / m ² , has tearing and tear strength in the longitudinal and transverse directions> 15 N.

According to the invention, the object is achieved by using a nonwoven fabric consisting of a nonwoven fabric impregnated with a polymer and having a basis weight of 180 to 350 g / m ² and tear strength in both the longitudinal and transverse directions> 15 N, the nonwoven fabric being made from melt-spun, aerodynamically stretched and multicomponent filaments with a titer of <2 dtex deposited directly to a nonwoven and the multicomponent filaments after pre-consolidation are at least 90% split and consolidated into super micro continuous filaments with a titer of <0.2 dtex and in which the nonwoven fabric with 20 up to 50% by weight of a polymer, based on the initial weight of the nonwoven, is impregnated as heel lining for the shoe industry.

The heel lining is preferably one in which the multicomponent continuous filament a bicomponent continuous filament made of two incompatible Polymers, especially a polyester and a polyamide. The Multicomponent continuous filament therefore has good cleavage and very favorable ratio of strength to basis weight.

The heel lining is preferably one in which the polyester content is in Multi-component continuous filament higher than the polyamide content, in particular in the range of the weight ratio of polyester to polyamide 1.1: 1 to 3: 1. The heel lining has a very textile handle and a good aging resistance.

A heel lining in which the multi-component continuous filaments are particularly preferred a cross section with orange-like multi-segment structure have, the segments alternately one of the two incompatible polymers.

The heel lining is preferably one in which the from the Multi-component continuous filaments formed nonwoven for pre-consolidation is precalanded. The material therefore has a very good quality Thickness uniformity.

A heel lining is also particularly preferred, in which at least one the incompatible polymers that form as a multi-component continuous filament an additive, such as color pigments, permanent antistatic agents and / or the additives influencing hydrophilic or hydrophobic properties in Contains amounts up to 15 wt .-%. The heel lining can thereby its lightfastness, the tendency to static charge, the Sweat transport or the moisture retention effect can be positively influenced. Furthermore, the addition of the color pigments to the dope enables Production of deep and abrasion-resistant colors.

A heel lining in which the Multicomponent continuous filament is not crimped because of the textile handle resulting from the good cleavage in super micro continuous filaments is guaranteed.

A heel lining in which the Nonwoven fabric with 20 to 50 wt .-% of a polymer, based on the Initial weight of the nonwoven is impregnated. The heel lining shows off comparable degrees of impregnation compared to the known synthetic Heel lining materials have superior strength properties.

The heel lining is advantageously one in which one of the sides has a Hot melt adhesive application is provided. Such a material is especially for suitable for further processing on automatic machines.

The method according to the invention for producing the heel lining consists in the fact that multi-component continuous filaments are spun from the melt, aerodynamically stretched and immediately laid down to form a fleece, pre-consolidation by pre-calendering or needling and the Non-woven fabric solidified by high pressure fluid jets and at the same time in Super micro continuous filaments with a titer <0.2 dtex split as well is then impregnated with a polymer. The products so obtained are very even in terms of their strength, because one There is largely isotropic thread distribution in the product. The products show no tendency to delamination and show high module values as well as input and Tear strength.

Another advantageous embodiment of the method is that the Solidification and splitting of the multi-component continuous filaments takes place that the pre-consolidated nonwoven fabric alternately several times from both High pressure water jets are applied to the sides. That kind of Solidification and splitting of the multi-component continuous filaments leads to very dense nonwovens with smooth surfaces.

The solidification and splitting of the multicomponent continuous filament is preferred on an aggregate with rotating sieve drums carried out. This form of the aggregates allows the construction to be very compact Investments.

In a particularly preferred manner, the impregnation of the predominantly Super micro continuous filaments of split and solidified fleece with one aqueous polyurethane or NBR latex dispersion. Thereby residues of solvent are avoided and impregnation with a Polymer made in a particularly environmentally friendly manner.

Preferably, the impregnated material becomes one more Subsequent treatment by grinding or buffing. Through this Measures can affect the finish and feel of the obtained material can be improved. By in the structure contained microfilaments creates a particularly fine and noble, nubuck-like surface that is very similar to that of natural leather.

example

A non-woven fabric with a basis weight of approx. 160 g / m ^{2 is} produced from a multi-component continuous filament consisting of 65% by weight of poly (ethylene terephthalate) and 35% by weight of poly (hexamethylene adipamide). The starting filaments have a titer of approx. 1.8 dtex and consist of 16 segments, with polyester and polyamide segments alternating like orange slits around a central axis. The melt-spun, multicomponent filaments are stretched aerodynamically and placed randomly on a belt. The nonwoven fabric pile thus obtained is subjected to a pre-calendering at temperatures of approximately 95 ° C. and a pressure of approximately 100 bar. After mechanical pre-consolidation by needling, water jet treatment is carried out at approx. 100 bar water pressure. Subsequently, the multi-component continuous filaments are split into super-micro continuous filaments with a titer of approx. 0.1 dtex and the nonwoven is consolidated with the help of high-pressure water jets. The treatment is carried out twice from both sides at water pressures of 250 to 300 bar and on sieve pads with a mesh size of 60 to 100 mesh. The fleece is then dried and subjected to polymer impregnation using a dry-on-wet treatment with NBR latex. Approx. 125% by weight of NBR, based on the initial weight of the nonwoven, is applied and fixed by drying at 180 ° C. After grinding, a heel lining with a weight of 260 g / m ² and a thickness of 0.75 mm is obtained.

Comparative example

A nonwoven fabric is made from polyester and polypropylene staple fibers by intensive needling and impregnated with NBR. A heel lining with a basis weight of 320 g / m ² and a thickness of 0.85 mm is obtained by splitting.

A comparison of the strength values and the abrasion resistance is summarized in Table 1 below. The abrasion resistance was determined in such a way that a test specimen with 90 mm  is clamped in a rotary clamping head and loaded with a scouring pressure of 2.8 N / cm ² . The angle of rotation of the clamping head is 50 degrees. The test sample is tested against a scouring element that has diamonds on its surface. The test sample is wetted with water and cycled back and forth, a scrubbing cycle consisting of 300 back and forth movements, which is followed by a visual assessment based on a grading template.

Claims (10)

1. The use of a nonwoven fabric comprising a polymer-impregnated nonwoven fabric having basis weights of from 180 to 350 g/m² and tear strengths of > 15 N not only in the longitudinal but also in the transverse direction, the nonwoven fabric comprising multicomponent filaments having a linear density of < 2 dtex which are spun from the melt, aerodynamically stretched, directly laid down to form a web and subjected to a pre-consolidating operation before being at least 90% split into supermicrofilaments having a linear density of < 0.2 dtex and consolidated, and the nonwoven fabric being impregnated with from 20 to 50% by weight of a polymer, based on the starting weight of the nonwoven fabric, as a heel lining for the shoe industry.
2. The use according to claim 1, wherein the multicomponent filament of the nonwoven fabric is a bicomponent filament of two incompatible polymers, especially of a polyester and a polyamide.
3. The use according to claim 2, wherein the polyester fraction in the multicomponent filament of the nonwoven fabric is larger than the polyamide fraction.
4. The use according to claim 3, wherein the weight ratio of the polyester fraction to the polyamide fraction in the multicomponent filament of the nonwoven fabric is in the range from 1.1:1 to 3:1.
5. The use according to any one of claims 2 to 4, wherein the multicomponent filaments of the nonwoven fabric have a cross section having an orangelike multisegment structure in which segments each containing one of the two incompatible polymers alternate.
6. The use according to any one of claims 1 to 5, wherein the nonwoven fabric formed from the multicomponent filaments is precalendered before preconsolidation.
7. The use according to any one of claims 2 to 6, wherein at least one of the incompatible polymers of the nonwoven fabric forming the multicomponent filament contains an additive, such as colour pigments, permanently active antistats and/or hydrophilic or hydrophobic modifiers, in an amount of up to 15% by weight.
8. The use according to any one of claim 1 to 7, wherein the multicomponent filament of the nonwoven fabric is uncrimped.
9. The use according to any one of claims 1 to 8, wherein the nonwoven fabric possesses a high-quality, nubucklike surface after abrading, due to microfilament ends bared at the surface.
10. The use according to any one of claims 1 to 9, wherein one of the sides of the nonwoven fabric is provided with an application of hotmelt adhesive.