KR20060115567A - Composition of high-frequency adhesive footwear sheet - Google Patents

Abstract

Provided is a composition of a high-frequency adhesive sheet for footwear, which ensures transparency, adhesiveness and cuttability of a thermoplastic polyurethane sheet attached to the upper shell of a shoe. The composition of a high-frequency adhesive sheet is based on thermoplastic polyurethane and is attached to upper shells for footwear via high-frequency treatment. The composition comprises an aromatic ester resin. The aromatic ester resin includes a polycondensate of an aromatic dibasic acid with a low-molecular weight dihydric alcohol. The aromatic dibasic acid includes terephthalic acid, isophthalic acid, adipic acid or phthalic anhydride. The low-molecular weight dihydric alcohol includes ethylene glycol, propylene glycol, butylene glycol or neopentyl glycol.

Description

Composition of high-frequency adhesive sheet for footwear

The present invention relates to a sheet to be attached to the upper of the shoe, and more particularly to a composition of the high-frequency adhesive sheet for shoes with improved adhesion, transparency and cutting properties.

Typically, the upper structure of the shoe is optionally sewn together by cutting at least two pieces of fabric and sewn sheets of natural leather, artificial leather or synthetic resin, etc., in various forms to embellish the exterior of the shoe thereon. The upper was constructed.

However, since the upper configuration requires long sewing work and sophisticated design, skilled sewing workers and skills are required, and high wages and long working hours of workers raise the price of the product, thus making them competitive externally. There was a downside to losing it.

Meanwhile, in order to solve the above problems, conventionally, a polyvinyl chloride sheet (hereinafter, referred to as a 'PVC' sheet) treated with printing is bonded to the upper by using a high frequency heating method. On the other hand, PVC sheet is gradually excluded due to environmental problems while excellent adhesiveness.

Therefore, various polymer materials are used today to replace PVC sheets which have a fatal effect on environmental pollution, and among them, thermoplastic polyurethane (hereinafter referred to as 'TPU') that can exhibit physical properties closest to PVC. Was used to prepare the sheet.

However, the TPU sheet has a disadvantage in that the toughness of the resin is not easy to cut and the adhesion to a specific substrate (for example, a woven fiber fabric) is significantly reduced.

In addition, various attempts have been made to improve the cutting property of the TPU sheet, and thus, the cutting property is somewhat improved, but the adhesion to the substrate is not improved, but rather weak.

Accordingly, an object of the present invention for solving the problems as described above is to provide a composition of a high-frequency adhesive sheet for shoes that can improve the cutting property and secure the adhesive force of the TPU sheet and increase the transparency of the TPU sheet during high frequency operation.

Another object of the present invention to provide a composition of a high-frequency adhesive sheet for shoes that can improve the cutting properties without significantly affecting the adhesiveness and transparency.

Another object of the present invention is to provide a composition of a high-frequency adhesive sheet for shoes that can shorten the high frequency working time and reduce the process cost.

Still another object of the present invention is to provide a composition that can be used as a high-frequency gluing sheet for shoes by recycling the waste scrap TPU used as a high-frequency sheet.

Hereinafter, the present invention will be described with reference to Examples. However, the embodiments according to the present invention may be modified in various other forms. Preferably, the compounding ratio of the limited composition presented in each of the embodiments to be described below is intended to achieve the best effect, and thus the scope of the present invention is as follows. It should not be construed as limited to the embodiments described above. Embodiments of the present invention are provided to more clearly describe the present invention to those skilled in the art.

First, in order to improve the cutting property of the TPU sheet, the TPU sheet is blended with a resin having a lower melt viscosity than the TPU (for example, acrylic, ethylene-vinylacetate, styrene-butadiene-styrene, and rubber). Prepared. At this time, when using the resins, the selected resins were selected within a range that does not significantly affect the adhesiveness or transparency of the blended final resin, and as a result, the cutting property was improved, but it was found that the adhesiveness and transparency were somewhat inferior.

Therefore, in the present invention, in order to secure transparency, adhesiveness and cutting property of the TPU sheet mainly composed of an ester polyol and an aromatic isocyanate at the same time, a resin having a refractive index most similar to that of the TPU is preferably used, preferably an aromatic ester resin. Sheets were prepared.

That is, the present invention is 10 to 40% by weight of the condensation polymerization product of aromatic divalent acid and low molecular weight dihydric alcohol, 60 to 90% by weight of TPU, 0.5 to 3.0% by weight of yellowing agent, and 0.5 to 3.0% by weight of other additives. A high frequency adhesive sheet for was prepared.

At this time, a composition such as terephthalic acid (Terephthalic acid), isophthalic acid (Isophthalic acid), adipic acid (Adipic acid) and phthalic anhydride (Phthalic anhydride) is used as the aromatic divalent acid.

In addition, the low molecular weight dihydric alcohol used in the present invention is a composition such as ethylene glycol (Ethylene glycol) and propylene glycol (Propylene glycol) and butylene glycol (Butylenes glycol) and neopentyl glycol (Neopentyl glycol).

Meanwhile, as described above, the aromatic ester resin (ie, a condensation polymer of aromatic dihydric acid and low molecular weight dihydric alcohol) used to improve transparency, adhesiveness, and cutting property of the TPU sheet may include the compositions shown in Table 1 below. And according to the compounding ratio. At this time, the composition and the compounding ratio specified in Table 1 is only one example and should not limit the scope of the present invention based on this.

Composition Compounding ratio (% by weight) Terephthalic acid 10-20 Isophthalic acid 15-25 Adipic acid 15-25 Phthalic anhydride 5-15 Neopentyl glycol 40-50

On the other hand, in the present invention, in order to minimize the use of pure TPU, the use of the remaining waste sheet (ie, waste scrap TPU) is used as a high-frequency sheet, and a general pure TPU may be blended thereto to manufacture a high-frequency adhesive sheet for shoes again. This will be easily understood by the following examples.

Hereinafter will be described in detail based on the preferred embodiment of the present invention, the present invention is not limited by the embodiment.

{Example 1}

A TPU sheet was prepared by blending a TPU having an hardness of 85 A, an aromatic ester resin, an ultraviolet stabilizer, and an anti-adhesive agent at a ratio of 85.0: 15.0: 1.0: 0.05.

{Example 2}

A TPU sheet having a hardness of 85 A, an aromatic ester resin, a pigment, an ultraviolet stabilizer, and a tackifier were blended in a ratio of 75.0: 25.0: 1.0: 1.0: 0.05.

{Example 3}

A TPU sheet having a hardness of 90 A, an aromatic ester resin, an ultraviolet stabilizer, and an anti-adhesive agent were blended in a ratio of 75.0: 25.0: 1.0: 0.05.

{Example 4}

A high-frequency adhesive sheet was prepared by combining 50% by weight of waste scrap TPU, 30% by weight of pure TPU, 20% by weight of aromatic ester resin, and a small amount of UV stabilizer and anti-stick agent. At this time, a very small amount of the UV stabilizer and the tackifier are added.

On the other hand, the sheet made of the composition of the present invention as described above, as a result of the test is superior to the conventional TPU sheet, it can be seen that the transparency and adhesion of the sheet is particularly improved.

That is, the TPU sheet of the present invention (preferably, a TPU sheet composed of a condensation polymer of an aromatic dihydric acid and a low molecular weight dihydric alcohol) has very good ink adhesion, and can be printed with an aqueous printing ink. The adhesion of the TPU sheet was not very good, but the TPU sheet of the present invention showed excellent adhesion to the mesh. In particular, the TPU sheet of the present invention was found to significantly shorten the working time compared to the prior art and also has a relatively good adhesion to the adherend.

As described above, the present invention is not only very good adhesion to the substrate (shoe upper) at room temperature, but also improve the cutting properties can significantly shorten the high frequency working time, and thus the work process and This has the advantage of reducing costs.

In addition, the present invention by blending the TPU and the aromatic ester-based resin improves the cutting property of the sheet during high frequency operation, and can increase the adhesive force between the sheet and the upper, in particular has the effect of maintaining the transparency of the sheet.

Claims (5)

In the composition of the sheet containing thermoplastic polyurethane as a main component and bonded to the upper for shoes by high frequency operation, A composition of a high frequency adhesive sheet for shoes comprising an aromatic ester resin. The method of claim 1, The aromatic ester resin composition of the high-frequency adhesive sheet for shoes, characterized in that the condensation polymerization of an aromatic divalent acid and a low molecular weight dihydric alcohol. The method of claim 2, The aromatic divalent acid is a composition of a high frequency adhesive sheet for shoes, characterized in that terephthalic acid or isophthalic acid or adipic acid or phthalic anhydride. The method of claim 2, The low molecular weight dihydric alcohol is ethylene glycol or propylene glycol or butylene glycol or neopentyl glycol composition of the high-frequency adhesive sheet for shoes, characterized in that. The method according to any one of claims 1 to 4, The thermoplastic polyurethane composition of the high-frequency adhesive sheet for shoes, characterized in that consisting of the TPU and the conventional TPU sheet in the form of waste scrap remaining after the high frequency operation.