KR20020061601A - Heel lining for use in the shoe industry - Google Patents

Abstract

The present invention is a heel lining for use in the footwear industry as a material consisting of a polymer impregnated nonwoven fabric having a surface area weight of 180 to 350 g / m ² and a chain tear strength greater than 15 N in longitudinal and transverse directions. ). The nonwoven fabric consists of a multicomponent endless filament with a fineness of less than 2 dtex that is melt spun, stretched aerodynamically and plated directly onto the nonwoven fabric. The multicomponent endless filaments are cured by dividing into ultrafine-endless filaments having a fineness of less than 0.2 dtex by at least 90% after precure.

Description

HEEL LINING FOR USE IN THE SHOE INDUSTRY

In the footwear industry, high abrasion resistant materials are used for the backing of shoes, the so-called heel caps. Such materials must, on the one hand, absorb the force exerted on the shoe by the foot, especially when moving longitudinally, and on the other hand, must withstand the frictional forces caused by the foot moving at least partially up and down in the shoe when walking. . Suede-shaped materials are traditionally used as heel lining to prevent inadvertent slippage of the foot from the shoe during walking, which prevents slipping out of the shoe through frictional contact with the foot or wearer's socks. .

In addition to heel linings made from natural materials, synthetic materials are also used. The synthetic materials are needle punched nonwovens which are simply produced by carding of polyester fibers, viscose fibers, polyamide fibers, polypropylene fibers or mixed fibers of the fibers during drying. For this purpose, fibrous webs having a surface area weight of 800 g / m ² or less are provided and are mechanically cured through high strength needling. The method step alone is already very time consuming and therefore quite expensive. In general, shrinkage of the needle punched nonwoven by hot air or steam is followed, which leads to further curing in terms of density adjustment desirable for the compression and use of the material. Styrene-Butadiene-Rubber-SBR or Nitrile-Butadiene-Rubber-NBR to achieve the required strength parameters, such as the first- and chain tear strength of the needlepunching nonwovens A thermosetting latex binder-dispersion, such as, is impregnated into the nonwoven fabric and then dried. The latex content amounts to about 30 to 60 weight percent of the impregnated nonwoven weight. The pretreated material is thus divided into two to four thin layers. The splitting process is borrowed from the nonwoven leather industry to increase productivity in nonwoven fabrication. The split product can be further polished to improve surface uniformity and visual roughness. Finally, the molten adhesive is applied to one of both sides to simplify later processing. In conventional synthetic heel linings, the unevenness of individual layers due to excessive differences in strength values in the longitudinal and transverse directions, the strength loss caused by the splitting of fiber bundles arranged vertically by needling, and the stitching surface This has the disadvantage of appearing.

The present invention relates to a heel lining for the footwear industry and a method of manufacturing the same.

An object of the present invention is a very suitable method for manufacturing the heel lining for footwear industry and having a first- and serial tear strength greater than 15 N in longitudinal and transverse directions at a surface area weight of 180 to 350 g / m ² . To provide.

This object is achieved by a heel lining consisting of a polymer impregnated nonwoven fabric having a surface area weight of 180 to 350 g / m ² and a chain tear strength greater than 15 N in longitudinal and transverse directions, the nonwoven fabric Is composed of multicomponent endless filaments with a fineness of less than 2 dtex, melt-spun, aerodynamically stretched and plated directly on the nonwoven fabric. The multicomponent endless filaments are cured by dividing into ultrafine-endless filaments having a fineness of less than 0.2 dtex by at least 90% after precure. These heel linings have high tensile strength and wear resistance at low surface area weights.

The heel lining is preferably a heel lining wherein the multicomponent endless filament is a bicomponent endless filament consisting of two incompatible polymers, in particular polyester and polyamide. The bicomponent endless filaments thereby have good splitability and have a very advantageous strength ratio to the surface area weight.

The heel lining is preferably a heel lining in which the polyester content in the multicomponent endless filament is higher than the polyamide content, in particular the weight ratio of the polyester content to the polyamide content is in the range of 1.1: 1 to 3: 1. The heel lining thus has a very fibrous feel and high aging resistance.

Particular preference is given to heel linings in which the multicomponent endless filaments have a cross section of an orange multisegment structure, wherein the segments each alternately contain one of two incompatible polymers.

The heel lining is preferably a heel lining in which a nonwoven fabric formed of multicomponent endless filaments undergoes a pre-calendering step for precure. The material thus has a very good thickness uniformity.

Furthermore, at least one of the incompatible polymers formed as multicomponent endless filaments is particularly preferably a heel lining containing dyes, additives such as permanent antistatic agents and / or additives that affect hydrophobicity or hydrophilicity in amounts up to 15 percent by weight. . Thereby the heel lining is positively influenced in terms of its high temperature-lightfastness, charging tendency, sweat-absorbing ability or dew-wetting effect (moisture: Feuchtigkeitstauwirkung) by moisture. In addition, the addition of dyes to the emission can result in a dark wear resistant color.

Also particularly preferred are heel linings in which the multicomponent endless filaments are not crimped. This is because the fibrous feel due to the excellent splitability into the ultra-endless filament is guaranteed.

According to the invention, particular preference is given to heel linings in which the nonwoven fabric is impregnated with 20 to 50% by weight of polymer relative to the initial weight of the nonwoven. Such heel linings have more superior strength properties at comparable impregnation concentrations than known synthetic heel lining materials.

Also preferred is a heel lining in which a molten adhesive is applied to one side. Such materials are particularly suitable for further processing via automated machines.

In the method for manufacturing a heel lining according to the present invention, a multi-component endless filament is melt-spun and stretched aerodynamically, then plated directly on a nonwoven fabric, and precured through precalendering or needling, and the nonwoven fabric is a high-pressure liquid. It is cured by spraying, at the same time split into ultra-endless filaments with fineness less than 0.2 dtex and then impregnating the polymer into the nonwoven fabric. The product thus obtained is very homogeneous in view of its strength resistance, because it has isotropic yarn splitting properties, does not exhibit a tendency to crack and has a high modulus value and initial / chain tear strength.

In another preferred embodiment of the method, the high pressure waterjet is applied to the sides of the precured nonwoven alternately several times to cure and split the multicomponent endless filaments. This method of hardening and splitting multicomponent endless filaments results in a very dense nonwoven fabric with a smooth surface.

Preferably the precure and splitting of the multicomponent endless filaments is carried out on a device equipped with a rotary sieve. This type of device can be installed very simply.

In a particularly preferred manner, the nonwoven fabric, which is mostly divided into ultrafine-endless filaments, is impregnated with an aqueous polyurethane dispersion or an aqueous NBR-latex dispersion. This leaves no solvent residues and the polymer impregnation is carried out in a very environmentally friendly manner.

Preferably the impregnated material is again subjected to a post treatment step by rubbing and buffing. Such measures can further improve the surface condition and feel of the material obtained. At this time, the microfilament contained in the structure forms a fine and luxurious cowhide surface very similar to the surface of natural leather.

A nonwoven web having a surface area weight of about 160 g / m ² is produced from a multicomponent endless filament consisting of 65 weight percent poly (ethyleneterephthalate) and 35 weight percent poly (hexamethyleneadipamide). The original filament has a fineness of about 1.8 dtex and consists of 16 segments in which the polyester and polyamide segments appear alternately like orange divisions about the central axis. The melt-spun multicomponent endless filaments are aerodynamically stretched and irregularly plated on one band. The resulting nonwoven web is then subjected to a pre-calendering step at a temperature of about 95 ° C. and a pressure of about 100 bar. After the mechanical precure by needling, the waterjet treatment is carried out at a water pressure of about 100 bar. The multicomponent endless filaments are then divided into ultra-endless filaments having a fineness of about 0.1 dtex, and the nonwoven fabric is precured by high pressure waterjet. The waterjet processing is carried out twice on each side at a hydraulic pressure of 250 to 300 bar on a sieve support having a mesh size of 60 to 100 mesh. The nonwoven fabric is then dried and the dried nonwoven fabric is impregnated with a polymer through a dry on wet process using NMR-latex. About 125% by weight of NBR relative to the initial weight of the nonwoven is applied and fixed by drying at 180 ° C. After the grinding process, a heel lining having a weight of 260 g / m ² and a thickness of 0.75 mm is produced.

Comparative Example

Nonwoven fabrics are made by high-density needling from polyester-staple fibers and polypropylene-staple fibers, and the nonwoven fabric is impregnated with NBR. The splitting process produces a heel lining with a weight of 320 g / m ² and a thickness of 0.85 mm.

Table 1 below compares the strength value and the wear resistance. Where the wear resistance is 90 mm Tighten the test piece into the rotary fastener and measure by applying a wear pressure of 2.8 N / cm ² to the test piece. The angle of rotation of the fastener is 50 degrees. The test sample is tested for a wear member having a rhombus pattern on the surface. The test piece is moistened with water and repeatedly moved back and forth, where one wear cycle consists of 300 movements back and forth. Visual judgment is then made according to the evaluation model.

Example Comparative Example weight g / m ² 260 320 thickness mm 0.75 0.85 surface Note 1.0 1.0 10% modulus (vertical) N / 5cm 220 310 10% modulus (horizontal) N / 5cm 160 85 Chain Tear Strength (Portrait) N 21 10 Chain Tear Strength (Landscape) N 21 10 Wear (according to WN 3147/1) Note 1.0 1.0-1.5

Claims (16)

A heel lining for use in the footwear industry as a material consisting of a polymer impregnated nonwoven fabric having a surface area weight of 180 to 350 g / m ² and a chain tear strength greater than 15 N in longitudinal and transverse directions, The nonwoven fabric consists of a multicomponent endless filament with a fineness of less than 2 dtex, melt-spun, aerodynamically stretched and plated directly onto the nonwoven fabric, the multicomponent endless filament having less than 0.2 dtex by at least 90% after precure. Heel lining divided into ultra-fine endless filaments with fineness. The method of claim 1, Wherein said multicomponent endless filament is a bicomponent endless filament consisting of two incompatible polymers, in particular polyester and polyamide. The method of claim 2, A heel lining, characterized in that the polyester content in the multicomponent endless filament is higher than the polyamide content. The method of claim 3, wherein A heel lining, characterized in that the weight ratio of polyester content to polyamide content in the multicomponent endless filaments is 1.1: 1 to 3: 1. The method according to any one of claims 1 to 4, Wherein said multicomponent endless filaments have a cross section of an orange multisegment structure, said segments each containing one of two incompatible polymers alternately. The method according to any one of claims 1 to 5, Heel lining, characterized in that the nonwoven fabric formed of the multi-component endless filament is subjected to a pre-calendering step for preliminary curing. The method according to any one of claims 1 to 6, At least one of the incompatible polymers forming the multicomponent endless filaments contains a dye, an additive such as a permanent antistatic agent, and / or an additive that affects hydrophobicity or hydrophilicity in an amount of up to 15 weight percent. . The method according to any one of claims 1 to 7, A heel lining, wherein the multicomponent endless filaments are not crimped. The method according to any one of claims 1 to 8, Wherein the nonwoven fabric is impregnated with 20 to 50 weight percent of polymer relative to its initial weight. The method according to any one of claims 1 to 9, A heel lining characterized in that a high quality skin-like surface caused by microfilament ends exposed to the surface is produced after the polishing process. The method according to any one of claims 1 to 10, Heel lining characterized in that the molten adhesive is applied to one side. A method for producing a heel lining according to any one of claims 1 to 11, The multicomponent endless filaments are melt spun and aerodynamically stretched and plated directly onto the nonwoven fabric, precure is performed, and the nonwoven fabric is cured by high pressure liquid spraying and simultaneously with ultrafine-endless filaments having a fineness of less than 0.2 dtex. Divided, and then the polymer is impregnated and / or applied to the nonwoven fabric. The method of claim 12, Wherein the curing and splitting of the multicomponent endless filaments is performed in such a way that high pressure liquid jets are alternately applied to both sides of the precured nonwoven fabric. The method of claim 13, Characterized in that it is carried out on a device with a rotary sieve. The method according to any one of claims 12 to 14, Impregnation of the polymer is carried out using an aqueous polyurethane-latex dispersion. The method according to any one of claims 12 to 15, A post-treatment by rubbing or buffing is performed.