KR20100056629A - Thermoplastic polyurethane foam films - Google Patents

Abstract

PURPOSE: A method for manufacturing a thermoplastic poly urethane foam film for high-frequency bonding and a thermoplastic poly urethane foam film manufactured by the same are provided to completely remove surface nonuniformity of a foaming TPU film and to reduce the weight of a TPU film over 20%. CONSTITUTION: A method for manufacturing a thermoplastic poly urethane foam film for high-frequency bonding using a T-die extruder comprises following steps. Thermoplastic poly urethane is foamed and the foamed thermoplastic poly urethane is extruded by the T-die extruder at a time so that the thermoplastic poly urethane foam film is manufactured.

Description

Manufacturing method of thermoplastic polyurethane foam film for high frequency bonding and thermoplastic polyurethane foam film produced by the above method {THERMOPLASTIC POLYURETHANE FOAM FILMS}

The present invention relates to a method of manufacturing a thermoplastic polyurethane film for high frequency adhesion, which is used in a variety of industries, and more particularly, to form a single layer by an extrusion method in order to realize a lightweight and uniform surface of the thermoplastic polyurethane film. The present invention relates to a method for producing a thermoplastic polyurethane foam film for high frequency adhesion, which can produce a multilayer film made of a film or a foam layer and a non-foaming layer, and a thermoplastic polyurethane foam film produced by the method.

As is well known, the footwear industry has used a variety of materials for the decoration of shoe uppers. In particular, recently, a technique of screen printing polyvinyl chloride-based or polyurethane-based films in various colors and then bonding them to shoe uppers using a high frequency fusion method is widely used. Such high frequency work enables the brilliant design of shoes and the three-dimensional design, which contributes to the high quality of shoes.

However, polyvinyl chloride-based film has been used a lot because of the low manufacturing cost, but in recent years due to the increasingly severe environmental regulations that use is very strictly regulated. As a solution for this, many thermoplastic polyurethane (TPU) -based films are used. The TPU can be freely manufactured in various hardness ranges without the use of a plasticizer, and has excellent elasticity and It is a very good material that can maintain durability.

Although such a TPU is a material having excellent physical properties, the price of the material is relatively high, which is a burden on the manufacturing cost of the shoe. Also, since the specific gravity of the polyurethane film material is about 1.2, the overall weight of the shoe is used when a large amount is used. This has led to an increase, which has a detrimental effect on the recent trend of lightweight shoes.

On the other hand, in recent years there have been many attempts to solve the disadvantages of the price and specific gravity of the TPU film. Among them, attempts have been made to lower specific gravity by foaming the film using foam in the process of manufacturing the TPU film, and these products are actually manufactured and used.

However, these were all limited to film production by calendering process, and the foamed film thus produced is not easy to use directly due to its uneven surface and thickness, and has many limitations in use. It was accompanied. In addition, most of the high-frequency bonding process rarely uses the film itself, and the screen is printed on the surface to make a colorful decoration, and then only a predetermined portion is fused and bonded by high-frequency operation. When the surface of the TPU film is not smooth, The printing was not smooth and the surface was not clean even after the high frequency work, so there was a disadvantage in that a large amount of product defects occurred.

The present invention is to produce a TPU film for high-frequency adhesion, to manufacture a film through T-die extrusion rather than a calendering process to foam the TPU using a foam to reduce the weight of the TPU, TPU film composed of a single layer A method of manufacturing a thermoplastic polyurethane foam film for high frequency bonding and a thermoplastic polyurethane prepared by the above method that can produce a multilayer foam film having excellent surface smoothness by foaming only a middle layer or a lower layer without foaming the top layer as well as the method of manufacture. The purpose is to provide a foam film.

In addition, the present invention is a method for producing a thermoplastic polyurethane foamed film in a single operation by co-extrusion (multi-layered film) through a multi-layer film extruder rather than a composite and thermoplastic polyurethane foam produced by the above method The purpose is to provide a film.

In addition, the present invention provides a method for producing a thermoplastic polyurethane foamed film for high frequency adhesion and thermoplastic polyurethane foamed film prepared by the above method that can realize not only the weight of the thermoplastic polyurethane film but also the uniformity of the surface and thickness of the film. The purpose is.

The present invention comprises a plurality of chambers, each of the chambers is a method for producing a film for high-frequency bonding using a conventional T-die extruder provided with a cylinder, an adapter and a die, wherein each of the thermoplastic polyurethane in each chamber After filling, the remaining chambers except for one of the chambers were filled with styrene butadiene styrene copolymer and foam, respectively, to foam thermoplastic polyurethane, and then the foamed thermoplastic polyurethane and non-foamed thermoplastic polyurethane were filled with T. Simultaneously extruding with a die extruder, the top layer forms a non-foaming layer and the bottom layer forms a foaming layer.

In addition, the present invention is characterized in that the specific gravity of the thermoplastic polyurethane foam film for high frequency adhesion is 0.6 ~ 1.1.

In addition, in the present invention, the auxiliary workability adjusting resin such as styrene butadiene styrene copolymer, ethylene vinyl acetate copolymer or styrene acrylonitrile copolymer may be used in an amount of 5 to 20 parts by weight based on 95 to 80 parts by weight of thermoplastic polyurethane. It is characterized by adjusting the viscosity of the resin to be extruded.

The TPU film used for high frequency bonding produced by the present invention could be lighter than 20% in weight, and completely solved the surface unevenness which was a problem in the conventional foamed TPU film. This made it possible to produce a low specific gravity high-frequency adhesive TPU foam film suitable for use as a high frequency shoe material.

In addition, the present invention has the advantage that can be achieved not only genuine polyurethane resin but also recycled polyurethane resin in the same way as to achieve breakthrough cost reduction and resource recycling.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. In the following detailed description, exemplary embodiments of the present invention will be described in order to accomplish the above-mentioned technical problems. And other embodiments that can be presented with the present invention are replaced by the description in the configuration of the present invention.

The present invention embodies the hardening of the TPU film for high frequency adhesion, which is frequently used during the manufacturing process of shoes, and also selectively foams only the middle layer or the lower layer except the top layer as well as the foamed and lightweight single layer film, and has excellent smoothness of the film surface. It is intended to implement a method of manufacturing a thermoplastic polyurethane foam film for high frequency adhesion that can reduce the specific gravity of the entire film by producing a foam film.

For this purpose, not only the foam for foaming the TPU should be specifically disclosed when the TPU is made of a high frequency adhesive film, but also the specific composition constituting the TPU film together with the foam should be described. And specific extrusion operating conditions for producing a TPU foam film by extrusion (i.e., co-extrusion) using a conventional T-die extruder should be disclosed, and in particular the composition of the TPU foam film consisting of a multilayer as mentioned above It should be specifically disclosed.

The foam used in the present invention is a capsule foam which is generally commercially used and contains a low boiling point organic material, and the outside is a foam that is protected by a capsule of acrylic or vinyl resin. These foams are usually several microns or less in size, and various products are commercially available according to the foam starting temperature and the maximum foaming temperature. In the present invention, foams that can be used for the extrusion process of TPU films are selected from these products. Used. Specifically, a foam having a foaming start temperature of 120 ° C. or higher and a maximum foaming temperature of 150 to 180 ° C. was used.

In addition, the film manufacturing method used in the present invention was manufactured by the extrusion method using a T-die extruder, not a film processing using a conventional calendar, using a multi-layer extruder capable of extruding two or more layers as well as a single layer film. It was. Specifically, a multilayer extruder capable of co-extrusion of up to three layers of films was used. In the case of using a conventional single-layer extruder, there was an unreasonable aspect of repeating multiple extrusions and composites in order to produce a multilayer film, and the multilayer extruder used in the present invention is a very efficient manufacturing apparatus that can solve such repeated extrusion at once. That is, as a multi-layer T-die extruder capable of simultaneously extruding films of different layers at the same time to finally produce a single film in which these functions are combined, since the extruder is a known technique, the present invention will not be described in detail. It will be omitted.

In addition, a method of manufacturing a multilayer film using the extrusion apparatus is disclosed in Korean Patent Application Publication No. 10-2007-0113542 filed on May 25, 2006 and filed on November 29, 2006. And a multi-layered sheet manufactured by the above method).

In addition, the TPU material used in the present invention includes not only a genuine TPU but also a recycled TPU which reprocesses a TPU film in a scrap state generated by various paths after film processing. At this time, the regenerated TPU is described in detail in the application No. 10-2008-113102 filed by the applicant of November 14, 2008. In addition, the method for manufacturing the regenerated TPU is outlined. After the scrap generated in the high frequency process is pulverized, the pulverized scrap is extruded while removing foreign matters to form pellets. After mixing the phosphorus TPU, it is made of a process of producing a regenerated TPU by extruding while removing the foreign matter.

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

{Example 1}

Example 1 is a method for producing a TPU foam film consisting of a single layer, the composition and the compounding ratio of each layer when the TPU film is prepared in detail in Table 1.

Upper layer (part by weight) Middle layer (weight part) Lower layer (weight part) 85 A hardness TPU 85 85 85 SBS 15 15 15 Yellowing masterbatch 3.5 3.5 3.5 White Pigment Masterbatch 6.5 6.5 - Foam 1.0 ~ 5.0 1.0 ~ 5.0 1.0 ~ 5.0

At this time, SBS is a styrene-butadiene-styrene copolymer, the viscosity of the resin after the foaming reaction is excessively lowered to prevent problems caused by low viscosity during the production process, such as problems of thickness adjustment It was added to increase the viscosity. In order to improve the extrusion viscosity, more than 5 parts by weight of SBS (at this time, 95 parts by weight of TPU) was required. When the amount of SBS exceeded 20 parts by weight (at this time, 80 parts by weight of TPU), turbidity of the product was due to poor compatibility with the TPU. The appearance was not good, such as increased, 15 parts by weight was most appropriate.

The same applies to each of the following examples. In addition to SBS, an ethylene-vinylacetate copolymer (EVA) or a styrene-acrylonitrile copolymer (SAN) may be used for the same purpose. Of course, by using the TPU itself with a high viscosity, it is possible to solve the problem of thickness control during production without using SBS, EVA, SAN, etc. More specifically, the TPU with a melt index of 7g / 10min or less at a load of 175 degrees 2.16kg can be used to solve the problem of thickness control due to a decrease in viscosity, that is, production can be performed without using SBS. By using the auxiliary could increase the viscosity.

In addition, the yellowing masterbatch is a masterbatch of 20% UV absorber, 20% antioxidant, 40% TPU, the yellowing masterbatch is generally used in the range of 1 to 5 parts by weight, most preferably 2 ~ 4 parts by weight is used. The white pigment masterbatch is a masterbatch of 40% TiO ₂ , 1% antioxidant, 59% TPU. At this time, the yellowing masterbatch and the white pigment masterbatch made of the above composition is the masterbatch used the same in each of the examples below.

In addition, the foam is a capsule in the form of a capsule, as mentioned above, and has a slight yellow color in nature, so that the final appearance of the product may be yellowed. Improvement by addition.

A mixture consisting of the respective compositions as described above was filled into respective chambers installed in a conventional three-layer film extruder (i.e., known multi-layer T-die extruder) and then extruded simultaneously with foaming to produce a single layer foamed film. . At this time, the extrusion working temperature conditions of the extruder are shown in Table 2, and the mixing conditions of the upper layer, the middle layer and the lower layer of the TPU film were almost similar, so the operation was performed under the same temperature conditions.

Cylinder (℃) Adapter (℃) Dies (℃) Upper layer 170 175 180 185 185 185 180 180 180 180 180 Middle layer
Same temperature as upper layer substratum

Here, the cylinder, the adapter and the die is provided with heaters in each section as shown in FIG. 1, specifically, the cylinder is divided into four parts to install a heater, and the adapter is divided into two parts to install a heater. The dice were divided into five parts and heaters were respectively installed. The reason for installing the heater in each section and changing the temperature is to improve the workability, specifically, to prevent the resin from solidifying at both ends and to allow the molten resin to be extruded smoothly. .

The single-layer TPU film prepared according to the composition and the extrusion working temperature conditions showed the same shape on both sides of the foam on both sides, and this TPU film was difficult to use directly by itself. It is preferable to use after covering a surface.

In addition, the single-layer TPU film showed sufficient physical properties without problems for use for high frequency adhesion, which is shown in Table 3. In order to use in the high frequency process, the film was unfoamed at the time of extrusion work, the surface was flattened, the surface was printed on the surface, and the high frequency work was performed.

Properties Test result 300% modulus 80kgf / ㎠ The tensile strength 200kgf / ㎠ Elongation 600% Tear Strength 90kgf / cm importance 0.90

{Example 2}

Example 2 is also a method for producing a TPU foam film consisting of a single layer, is an embodiment for obtaining the maximum foaming ratio by increasing the amount of foam as much as possible than in Example 1. In Table 4, the composition and the mixing ratio of the single-layer TPU foam film are shown in detail.

Upper layer (part by weight) Middle layer (weight part) Lower layer (weight part) 85 A hardness TPU 85 85 85 SBS 15 15 15 Yellowing masterbatch 3.5 3.5 3.5 White Pigment Masterbatch 6.5 6.5 - Foam 5.0-10.0 5.0-10.0 5.0-10.0

In Example 2, the extrusion operation temperature conditions were applied in the same manner as the extrusion operation temperature conditions of Example 1 described above, the extrusion was performed, the test results are shown in Table 5.

Properties Test result 300% modulus 70kgf / ㎠ The tensile strength 170kgf / ㎠ Elongation 450% Tear Strength 80kgf / cm importance 0.75

{Example 3}

Example 3 is a method of manufacturing a multi-layer TPU foam film, the upper layer is an embodiment in which only the middle layer and the lower layer is foamed selectively without foaming. The composition and the mixing ratio of each layer when preparing the multilayer TPU foam film are shown in Table 6 in detail.

Upper layer (part by weight) Middle layer (weight part) Lower layer (weight part) 85 A hardness TPU 100 85 85 SBS - 15 15 Yellowing masterbatch 3.5 3.5 3.5 White Pigment Masterbatch - 6.5 - Foam - 1.0-3.0 1.0-3.0

Extrusion operation temperature conditions for extruding the three-layer TPU foam film under the compounding conditions shown in Table 6 above are shown in Table 7.

Cylinder (℃) Adapter (℃) Dies (℃) Upper layer 167 172 178 178 182 182 178 178 178 178 178 Middle layer 170 175 180 185 185 185 180 180 180 180 180 substratum 170 175 180 185 185 185 180 180 180 180 180

As shown in Table 7, the compounding of the upper layer was not significantly different from the middle layer and the lower layer, so that the extrusion operation was performed in a nearly similar range.

Since the multilayer TPU foam film thus prepared is covered with a film that has not already foamed on its surface, it is not necessary to combine the film with a film not foamed separately. After printing on the upper layer, high frequency adhesion was performed, and as a result, a very clean surface was obtained and the appearance was excellent.

On the other hand, the configuration of the multilayer TPU foam film produced under the above mixing conditions and extrusion temperature conditions, as shown in Figure 2, the upper layer is composed of a non-foaming layer, the middle layer and the lower layer is composed of a foam layer. At this time, the physical properties of the multilayer TPU foam film are shown in Table 8.

Properties Test result 300% modulus 110kgf / ㎠ The tensile strength 320kgf / ㎠ Elongation 500% Tear Strength 93kgf / cm importance 1.07

{Example 4}

Example 4 is also a method for manufacturing a TPU foam film made of a multi-layer, to increase the amount of the foam to about 2 times than in Example 3 to further reduce the specific gravity. In Table 9, the composition and composition ratio of the multilayer TPU foam film were shown in detail, and the extrusion operation was performed under the same extrusion working temperature conditions as Example 3 described above.

Upper layer (part by weight) Middle layer (weight part) Lower layer (weight part) 85 A hardness TPU 100 85 85 SBS - 15 15 Yellowing masterbatch 3.5 3.5 3.5 White Pigment Masterbatch - 6.5 - Foam - 3.0-6.0 3.0-6.0

Although the specific gravity was further lowered by increasing the amount of foam used as above, the upper layer was not foamed, so it was able to maintain a very clean state, and the test results are shown in Table 10 in detail.

Properties Test result 300% modulus 100kgf / ㎠ The tensile strength 290kgf / ㎠ Elongation 530% Tear Strength 90kgf / cm importance 0.85

{Example 5}

Example 5 is an example for evaluating the minimum specific gravity that can be produced with the maximum amount of foam input, the composition and compounding ratio of the multilayer TPU foam film in Table 11, the physical properties of the film in Table 12. At this time, the extrusion working temperature conditions were the same as those in Example 3 described above.

Upper layer (part by weight) Middle layer (weight part) Lower layer (weight part) 85 A hardness TPU 100 85 85 SBS - 15 15 Yellowing masterbatch 3.5 3.5 3.5 White Pigment Masterbatch - 6.5 - Foam - 6.0-10.0 6.0-10.0

Properties Test result 300% modulus 90kgf / ㎠ The tensile strength 250kgf / ㎠ Elongation 600% Tear Strength 88kgf / cm importance 0.60

Looking at the test results up to Example 5 as described above, the specific gravity of the film was 1.2 was lowered to 0.70, and further foam input is not beautiful appearance of the product due to the difficulty of adding the raw material into the extruder and excessive foaming We couldn't make a good product because of the failure.

In each of the examples below, the composition, the mixing ratio, the extrusion operation temperature conditions and the test results when preparing the multilayer TPU foam film using the above-mentioned regenerated TPU are shown in detail.

{Example 6}

The recycled TPU used in Example 6 is a polyurethane resin obtained by reprocessing the scrap generated in the high frequency bonding process during the shoe manufacturing process. The resin is produced separately by mixing the genuine TPU in a constant ratio during reprocessing because the properties of the polyurethane, such as yellowing and degradation of the hydrolysis occurs when repeated use. In addition, since the recycled TPU is in an opaque state because it contains a large amount of foreign matter such as ink due to the characteristics of the scrap, there is no need to use a white masterbatch because there is no yellowing tendency felt when using a genuine TPU.

Therefore, in the present invention, the formulation of the middle layer and the lower layer could be made exactly the same, and of course, it is also possible to vary the formulation of the middle layer and the lower layer as necessary. Table 13 specifically shows the compounding ratio when using a regenerated TPU.

Upper layer (part by weight) Middle layer (weight part) Lower layer (weight part) Playback TPU (Colored) 100 85
Same as mezzanine
Compounding cost
SBS - 15 Yellowing masterbatch 3 3 Foam - 1.0-3.0

For recycled TPUs, there is a slight difference between the original TPU and the extrusion operation temperature. However, it does not always have the temperature conditions shown in Table 14, and there are always some deviations depending on the condition of the scrap. Table 14 below shows the extrusion working temperature conditions when using a recycled TPU.

Cylinder (℃) Adapter (℃) Dies (℃) Upper layer 175 180 185 185 187 187 185 185 185 185 185 Middle layer 170 175 180 183 183 183 178 178 178 178 178 substratum 170 175 180 183 183 183 178 178 178 178 178

When the regenerated TPU was used as described above, there was a slight change in the tensile strength and elongation of the foamed film, but there was no problem in using it for high frequency bonding. Table 15 specifically shows the physical properties of the multilayer TPU foam film obtained in Example 6.

Properties Test result 300% modulus 118kgf / ㎠ The tensile strength 220kgf / ㎠ Elongation 420% Tear Strength 97kgf / cm importance 1.06

{Example 7}

Example 7 was to increase the content of the foam while using the regenerated TPU, Table 16 shows the compounding ratio of each composition, the test results are shown in Table 17 specifically. Extrusion operation temperature conditions were extrusion operations under the same temperature conditions as Example 6 described above.

Upper layer (part by weight) Middle layer (weight part) Lower layer (weight part) Playback TPU (Colored) 100 85
Same as mezzanine
Compounding cost
SBS - 15 Yellowing masterbatch 3 3 Foam - 3.0-6.0

Properties Test result 300% modulus 95kgf / ㎠ The tensile strength 200kgf / ㎠ Elongation 450% Tear Strength 88kgf / cm importance 0.85

The TPU foam film extruded at the compounding ratio was able to lower specific gravity as in the case of using the genuine TPU of Example 4 described above, and the appearance of the product was excellent because the upper layer was covered with a non-foaming layer.

{Example 8}

In Example 8, a multi-layered TPU foam film was produced using a colorless regenerated TPU, the compounding ratio of which is shown in Table 18. At this time, the extrusion operation temperature conditions were the extrusion operation under the same temperature conditions as Example 3 described above.

Upper layer (part by weight) Middle layer (weight part) Lower layer (weight part)   Playback TPU (Colorless) 100 85 85 SBS - 15 15 Yellowing masterbatch 3.5 3.7 3.7 White Pigment Masterbatch - 6.5 - Foam 1.0-3.0 1.0-3.0

Among the recyclable TPU materials, there are some scraps that use the colored scraps mentioned in Examples 6 and 7 above, as well as those that are clearer and free of foreign matter, resulting in a colorless (ie transparent or translucent) film. The recycled TPU used in Example 8 was made using this colorless scrap. Particularly, in this experiment, a recycled TPU made of scrap generated during the manufacturing of an airbag, a shock absorber component material for shoes, was used.

The colorless regenerated TPU used in Example 8 was prepared separately by mixing a certain amount of genuine TPU with scrap during regeneration, similar to the colored regenerated TPUs mentioned in Examples 6 and 7. In addition, in Example 8, since it is in a transparent or translucent state, yellowing tendency can be felt as in Example 1, and a white masterbatch is added.

Meanwhile, the recycled TPU used in Example 8 uses scrap generated during the airbag manufacturing process, and the polyurethane used herein generally has a hardness range of about 90A, and thus the polyurethane of about 85A of hardness shown in the above-described embodiments. Modulus tended to be considerably higher than that. In addition, the appearance of the product was very excellent as in the above-described embodiments, there was no particular problem during high-frequency work after printing and showed excellent workability. Test results of Example 8 are shown in Table 19.

Properties Test result 300% modulus 145kgf / ㎠ The tensile strength 250kgf / ㎠ Elongation 425% Tear Strength 110kgf / cm importance 1.08

{Example 9}

In Example 9, only the middle layer of the entire film was foamed, and the upper layer and the lower layer were coextruded TPUs without foaming.

Upper layer (part by weight) Middle layer (weight part) Lower layer (weight part)   Playback TPU (Colorless) 100 85 100 SBS - 15 - Yellowing masterbatch 3.5 3.7 3.5 White Pigment Masterbatch - 6.5 - Foam 1.0-3.0 -

In the case of the previous embodiment, the upper layer surface was not foamed, but the surface was smooth, while the lower layer surface was somewhat rough due to the foam layer and the naked eye foamed state could be directly confirmed, but the film prepared in Example 9 was smooth on both sides. The surface was maintained.

Properties Test result 300% modulus 200kgf / ㎠ The tensile strength 290kgf / ㎠ Elongation 480% Tear Strength 110kgf / cm importance 1.05

{Example 10}

The multilayer foam films for high frequency adhesion exemplified in the above embodiments were also capable of being combined with a prefabricated film having different functions for further functionality in the extrusion step. For example, the foamed film exiting the T-die was combined with the prepared hot melt film to prepare a multilayer foam film for high frequency bonding in which a hot melt layer was added to the lowermost layer.

Actually, in the high frequency work site, in order to improve the high frequency adhesive force, the adhesive force is often applied to the back side of the high frequency film before the high frequency work, and then the high frequency is performed to improve the adhesive force. It is possible to improve the high frequency adhesive force by laminating the hot melt on the lowermost layer of the high frequency film in the extrusion step, and also by reducing the process cost than the step of laminating after the extrusion is completed by laminating in the extrusion step.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view schematically showing a cylinder, an adapter, and a die in the configuration of a T-die extrusion apparatus for producing a multilayer TPU foam film used in the present invention.

Figure 2 is a view showing the configuration of a multilayer TPU foam film according to an embodiment of the present invention.

Figure 3 is a view showing the configuration of a multi-layer TPU foam film according to another embodiment of the present invention.

Claims (11)

In the method of manufacturing a film for high frequency bonding using a conventional T-die extruder, After foaming the thermoplastic polyurethane, it is extruded at a time by the T-die extruder to produce a foamed thermoplastic polyurethane film, the method of producing a thermoplastic polyurethane foam film for high-frequency adhesion. The method of claim 1, The film is made of a multi-layer, the top layer is formed of a non-foamed thermoplastic polyurethane layer, the lower layer of the bottom of the top layer is a method of manufacturing a thermoplastic polyurethane foam film for high-frequency adhesion, characterized in that formed by a foamed thermoplastic polyurethane layer. . The method of claim 2, The upper layer is formed by extruding a thermoplastic polyurethane, and the lower layer is a mixture of secondary polyurethane resin and foam for controlling workability such as thermoplastic polyurethane and styrene butadiene styrene copolymer or ethylene vinyl acetate copolymer or styrene acrylonitrile copolymer. Method of producing a thermoplastic polyurethane foam film for high frequency bonding, characterized in that the extrusion to form. The method of claim 3, The foam is a method of manufacturing a thermoplastic polyurethane foam film for high-frequency adhesion, characterized in that the inside contains a low boiling point organic material and the outside is a foam protected by a capsule of acrylic or vinyl resin. The method of claim 3, Auxiliary processability adjusting resins, such as the styrene butadiene styrene copolymer, ethylene vinyl acetate copolymer or styrene acrylonitrile copolymer, may be extruded using 5 to 20 parts by weight based on 95 to 80 parts by weight of the thermoplastic polyurethane. Method of producing a thermoplastic polyurethane foam film for high frequency bonding, characterized in that for controlling. The method according to any one of claims 1 to 5, The film has a specific gravity of 0.6 ~ 1.1 method of producing a thermoplastic polyurethane foam film for high frequency adhesion. The method according to any one of claims 1 to 5, For high frequency adhesion, the specific gravity is 0.6 ~ 1.1 using recycled recycled TPU or by using auxiliary processing control resin such as styrene butadiene styrene copolymer, ethylene vinyl acetate copolymer or styrene acrylonitrile copolymer. Method for producing a thermoplastic polyurethane foam film. The method according to any one of claims 1 to 5, In the T-die extrusion step, an additional layer is formed on the lowermost layer or the uppermost layer through a combination of a high-frequency adhesive thermoplastic polyurethane foam film that is extruded through the T-die and a hot melt or non-polyurethane non-foamed film already made of a film. Method for producing a thermoplastic polyurethane foam film for high frequency bonding. In the method of manufacturing a film for high frequency bonding using a conventional T-die extruder having a plurality of chambers, each chamber is provided with a cylinder, an adapter and a die, Each of the chambers is filled with thermoplastic polyurethane, and the remaining chambers except for one of the chambers include auxiliary styrene resins such as styrene butadiene styrene copolymer, ethylene vinyl acetate copolymer or styrene acrylonitrile copolymer. After filling the foams respectively to foam the thermoplastic polyurethane, the foamed thermoplastic polyurethane and the non-foamed thermoplastic polyurethane are simultaneously extruded with the T-die extruder, so that the uppermost layer forms a non-foamed layer and the lower layer forms a foamed layer. Method for producing a thermoplastic polyurethane foam film for high-frequency adhesion, characterized in that the process made. In the thermoplastic polyurethane film for high frequency bonding, A thermoplastic polyurethane layer is formed by simultaneously extruding a thermoplastic polyurethane, a mixture of auxiliary resins and foams for controlling workability such as styrene butadiene styrene copolymer, ethylene vinyl acetate copolymer or styrene acrylonitrile copolymer, and thermoplastic polyurethane at the same time. It is formed and the lower layer is a thermoplastic polyurethane foam film for high-frequency adhesion, characterized in that the foamed thermoplastic polyurethane layer is formed. In the thermoplastic polyurethane film for high frequency bonding, The mixture of thermoplastic polyurethane and styrene butadiene styrene copolymer or ethylene vinyl acetate copolymer or styrene acrylonitrile copolymer and auxiliary process control resin and foam is blended, and thermoplastic polyurethane is extruded at the same time so that the upper and lower layers are thermoplastic poly The urethane layer is formed, the middle layer is a thermoplastic polyurethane foam film for high-frequency adhesion, characterized in that the foamed thermoplastic polyurethane layer is formed.

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