JP2003329258A - Electrothermal carpet cover and cover manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a commodity customer to wash an electrothermal carpet cover at home at any time, to enable immersing for cleaning by a fully automatic washing machine, by making the whole of the electrothermal carpet cover relatively thin and light, and to obtain good durability for long use even if having thin thickness. <P>SOLUTION: Either one of a back side of a pile-shaped front surface material directly contacting with a user or a front side of a cushion back surface material close to an electrothermal element is surface melted. During keeping a melting state, the front surface material and the back surface material are immediately welded in the cold, and the back surface material is welded to the back side of the front surface material. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cover for an electric heating carpet which is relatively thin and excellent in durability because it does not have a urethane layer interposed between the cover and a method for manufacturing the cover.

[0002]

2. Description of the Related Art In a commercially available electric heating carpet, in many cases, an existing carpet is laid and fixed on a sheet-shaped electric heating main body to apply the carpet as a cover for the electric heating carpet. Conventional electric heating carpet covers are mainly tufted carpets that have a synthetic resin backing material applied by applying resin latex to the back surface of the carpet material.For high-end products, Wilton carpet or Axminster carpet is used as the carpet material. Sometimes used. As this type of carpet, a commercially available carpet in which a woven fabric or a knitted fabric is used as a base fabric, the surface of which is flocked and a backing fabric is attached is also applicable.

The existing carpet cover for electric heating carpet is considerably bulky and is difficult to fold or roll up into small pieces, so that it is difficult for the purchaser of the product to wash it at home at any time. No, you just have to clean it with a special shampoo cleaning. In this shampoo cleaning, a detergent is applied to the surface of a carpet, and it is foamed by a machine, and the foam is sucked by a machine. It is difficult to completely remove stains on the surface and the cleaning cost is very high. In addition, a tufted carpet having a backing material has a problem that the backing material swells and peels off by washing.

[0004]

[Problems to be Solved by the Invention]
In the knitted carpet disclosed in Japanese Patent No. 99864, a felt sheet is fused to the back side of the Meyer carpet fabric via urethane foam, which increases the elasticity of the whole and prolongs the service life. The problem of peeling is solved. The electric carpet cover disclosed in Japanese Patent No. 3252610 has a configuration similar to that of the above-mentioned knitted carpet, and enables washing in the washing machine and dry cleaning by limiting the length of the fluff and the basis weight. These carpets become thick due to the presence of the urethane foam layer between the carpet fabric and the felt sheet and require fairly advanced techniques even though they can be washed at home.

Further, since these carpets have a urethane foam layer, toxic gas is generated when they are incinerated at the time of disposal, and it takes time and effort to remove only the urethane foam layer in the case of recycling. Since this urethane foam layer is softer and weaker than the fiber portion, it is yellowed by the action of heat, and the urethane foam layer deteriorates and is easily damaged by repeated washing.

The present invention has been proposed in order to improve the above-mentioned problems associated with a conventional electric heating carpet cover, and since the electric heating carpet is relatively thin and light as a whole, it can be easily washed in a washing machine. The purpose is to provide a cover for. Another object of the present invention is to provide a cover for an electric heating carpet that does not generate a toxic gas even when incinerated and can be easily recycled. Another object of the present invention is to provide a method for quickly manufacturing a relatively thin and light electric carpet covering.

[0007]

In order to achieve the above object, a cover for an electric heating carpet according to the present invention comprises a surface material which is in direct contact with a user and a cushioning back surface material which is close to an electric heating main body. To do. In the cover of the present invention, the protruding fiber portion is raised on the entire front surface of the back surface material, and the front side of the back surface material including the protruding fiber portion is heat-melted and pressure-treated, so that the back surface material is mainly based on the protruding fiber portion. The entire surface is fused to the back side of the surface material.

In the cover of the present invention, the surface material is warp knitted carpet material, tufted carpet material, Wilton carpet material, fiber mat material, tatami mat, rather ground, synthetic resin sheet or cushion floor sheet, and the back material is needle punched. A felt-based material such as felt or a composite material of a felt base material is preferable. This back material is
The low melting point fiber having a melting point of 170 ° C. or less has a fineness of about 5.6 decitex or more and is about 10% by weight or more of the total amount. Is preferably added.

The cover manufacturing method according to the present invention is a manufacturing method having a broader concept than the cover for the electric heating carpet. In the cover manufacturing method of the present invention, either the back side of the pile-like surface material that is in direct contact with the user or the front side of the cushioning back surface material that is close to the electrothermal body is surface-melted. The back side of the surface material or the front side of the back surface material is immediately stuck in a cold state while the molten state is maintained, and the back surface material is directly fused to the back side of the surface material.

In the cover manufacturing method of the present invention, a felt-based material is used as a cushioning back surface material close to the electrothermal body, the entire front surface of the felt-based material is napped by needle punching, and the fluffed material front surface is melted. ,
While maintaining the molten state, it may be immediately bonded to a pile-like surface material and the back surface material may be directly fused to the back side of the surface material.

In the cover manufacturing method of the present invention, when running a pile-like surface material that is in direct contact with the user, it is possible to arrange the surface pattern vertically and horizontally through the pattern correction device. Then, either the back side of the surface material or the front side of the cushioning back surface material may be surface-melted, and the back surface material may be directly fused to the back side of the surface material. The pattern correcting device used may be a device for correcting the surface pattern itself or a device for correcting the woven or knitted structure of the surface material.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION A cover 1 for an electric heating carpet according to the present invention comprises a surface material that is in direct contact with a user and a cushioning back surface material that is close to an electric heating body, and as shown in FIG. For example, the warp knitted carpet material 2 is used as the surface material and the needle punch felt material 3 is used as the back surface material. This surface material is a pile-like material that feels good when it comes into contact with the user's skin, and includes tufted carpet cloth, Wilton carpet cloth, fiber mat cloth, tatami mat, rather ground,
Examples include synthetic resin sheets and cushion floor sheets. The backing material is preferably a felt-based material having a cushioning property, and in addition to a normal felt material or a non-woven fabric, a needle punch felt material or a composite material of felt base material can be exemplified.

To manufacture the cover of the present invention, either the back side of the surface material or the front side of the back surface material is surface-melted, and the surface material and the back surface material are immediately bonded to each other in a cold state while maintaining the molten state. For the back side of the surface material or the front side of the back surface material, it is desirable to select local heating means so that other parts are not melted when the surface is melted, and the surface thereof is required to be relatively easy to melt. As a local heating means, a heater may be installed close to the surface of the material to be melted. For example, it is preferable that the heating burners 5 (FIG. 4) are arranged horizontally in series and the surface is melted by the open flame 7.

The back side of the surface material to be melted or the front side of the back surface material contains at least a part of a fiber having a relatively low melting point which is melted by a local heating means so that the surface is easily melted. Holds the overall shape by other fibers that do not melt into. Therefore, the surface material and the back surface material can be used as long as they are materials that can be mixed-spun or blended with cotton or fibers. As described above, the surface material is a pile-based material and the back surface material is a cushioning felt-based material. Select the material.

In the present invention, a needle punched felt material or a composite material of felt base material is used as the back surface material from the viewpoints of cost and durability, for example, and the surface melting thereof is relatively easy. These felt-based materials 16 (FIG. 3) are made of a mat obtained by mixing normal fibers such as synthetic fibers and natural fibers and fibers having a low melting point and laminating the obtained wraps, and the mat is made into a felt by needle punching. There is. A mixture of at least two kinds of fibers may be uniformly formed by a known wrap forming method, then spread and laminated, and wraps produced by other than the card method can also be used. You may intervene.

The felt material 16 which is the back material is a fiber 10 on the low melting point side having a fineness of about 5.6 decitex or more.
It contains not less than wt% and not more than 90 wt% of one or more ordinary fibers. Generally, if the content of fibers on the low melting point side is 45% by weight, and the fineness is less than 5.6 decitex, the melt adhesive strength of the surface of the felt-based material becomes weak and the surface material and the back surface material are separated. It will be easier. The fineness of the fiber on the low melting point side can be up to 17 to 30 decitex.

On the other hand, the fineness of the fiber on the low melting point side is 17 to 3
If the content is 0 decitex and the content thereof is less than 10% by weight, the melted portion on the surface of the backing material tends to decrease.
As a result, the entire surface of the felt-based material 16 is incompletely fused, which may impair the performance of the cover material.

In the felt-based material 16, the fibers on the low melting point side need to be completely melted at the time of adhesion on the whole surface, and preferably have a melting point of 170 ° C. or lower, which is lower than that of normal fibers by about 50 ° C. or more. desirable. Examples of the fibers on the low melting point side having a melting point of 170 ° C. or lower include polyethylene, polypropylene, low melting point polyester, low melting point polyamide, and mixed fibers thereof. The low melting point fiber may be a low melting point polypropylene or polyester and a copolymer of ethylene or butene, and is a two-layer type such as a core-sheath or parallel type, or a multi-layer type composite fiber such as multiple parallel type or multi-core type. May be.

Further, the ordinary fibers generally have a fineness of about 3 to 6 decitex, and finer decitex fibers may be mixed to increase the sound absorbing performance. Examples of the ordinary fibers include synthetic fibers such as polyester, polypropylene, acrylic, nylon and aromatic polyamide, natural fibers such as wool and cotton, chemical fibers such as rayon and acetate, and fibers in which these are mixed with each other. As the ordinary fiber, relatively inexpensive polyester fiber is often used, and fluff (recycled recycled cotton) may be partially used.

The felt-based material 16 is the heating burner 5
It is preferable to appropriately treat the front side with a local heating means such as (FIG. 4) so that the front side is easily melted. For example,
As shown in FIG. 3, even if the protruding fiber portions 8 are formed on the entire front surface of the raw material and each protruding fiber portion is set to melt when heated, many low melting point fibers exist on the front side. It may be subjected to cotton spreading treatment. When integrated by needle punching, the protruding fiber portions 8 are often in the form of a loop, with each needle penetrating the felt-based material 16 to stand it up.

On the other hand, the warp knitted carpet material 2 which is a suitable surface material is knitted by using a known double Russell knitting machine, and the knitting machine is provided with two rows of latch needles and a guide bar is arranged above the latch needles. There is. The guide bar of the Russell knitting machine is generally 2 to 18 sheets for piles, and each two sheets are for the weft insertion yarn and the chain yarn of the base fabric. Usually, acrylic yarns and warp knitted base fabrics are used as pile yarns. Polyester yarn is used as. The pile yarn may be a synthetic yarn such as polyester yarn, nylon yarn, vinylon yarn, PVC yarn, natural fiber yarn such as cotton yarn, rayon yarn, wool yarn, silk yarn, cashmere yarn, etc., and blended fiber yarns thereof are also used. It is possible, and the pile yarn may be composed of two kinds of synthetic fiber yarn and natural fiber yarn.

In the double Russell knitting machine, the double knit material 10
(FIG. 5) is knitted and this is center cut to obtain two single-sided knitted fabrics 11. To perform center cutting of the double-knitted material 10 at the position A in FIG. 5, the double-knitted material 10 is continuously fed from the lower side to the upper side through the square in a knife cutting device (not shown). Is subjected to center cutting with an endless band knife that rotates horizontally, and after being made into two single-sided knitted fabrics 11, they are separated into left and right and wound around a roll.

The single-sided knitted fabric 11 (FIG. 5) is usually stuck on a belt and run in an automatic screen printing machine (not shown), and an accurate pattern 12 (FIG. 6) is printed on the pile surface.
Imprint. After this printing treatment, steaming, washing and drying are performed, and raising, shaving and finishing such as shirring and polisher are continuously performed to obtain a warp knitted carpet material 2.

The warp-knitted carpet material 2 is easily stretched in the lateral direction, and the front surface pattern 12 is easily deformed when it is conveyed to be entirely adhered to the back material as shown in FIG. For this reason, it is preferable that the carpet base 2 is arranged in the vertical and horizontal directions of the front surface pattern 12 through the pattern correcting device 14 (FIG. 4), and immediately after that, the front surface pattern of the back surface material is bonded. This pattern correction device is a device that constantly measures the surface pattern with a photoelectric tube or the like and corrects it immediately if pattern deviation occurs. Instead of this, it measures and corrects the woven or knit structure of the base cloth of the carpet material 2. May be used. By this correction, the design 12 of the surface material can easily achieve the product standard that can be sold as a cover for an electric heating carpet without bending the linear portion of the design as illustrated in FIG.

The front and back materials used in the present invention are shown in FIG.
As shown in (3), the surfaces are immediately cold-bonded while maintaining the molten state on the surface. This bonding is performed with a roller pair 18
Alternatively, the roller pair 18 is more advantageous in terms of continuous processing, and the roller pair may be composed of two or more stations. Immediately before passing through the roller pair 18, the back side of the surface material or the front side of the back surface material comes into contact with the open fire 7 of the burners 5 arranged in a horizontal series to melt the surface, and mainly the protruding fiber portion 8 and a part of the front side are To melt.

The felt-based material 16 which is the back surface material needs to be adjusted so as not to be melted to the back side thereof when coming into contact with the direct fire 7 of the heating burner 5. The warp knitted carpet material 2 and the felt-based material 16 are pressed by the roller pair 18 or a press, and the front side of the felt-based material is entirely fused and integrated with the back side of the warp-knitted carpet material 2.

In order to manufacture the cover 1 for an electric heating carpet as illustrated in FIG. 1, the cover material 19 is entirely fused.
After obtaining (FIG. 4), trimming is performed appropriately. In the cover 1 for the electric heating carpet, after trimming into an appropriate square, as shown in FIG.
Then, the surrounding sewing thread 20 is fixed to the cloth with resin to prevent fraying, if desired.

The cover 1 for an electric heating carpet is excellent in durability and heat resistance in a harsh use environment where it is subjected to a pedaling pressure, and since the overall basis weight is 500 to 1000 g / m ^2, it is lighter than its thickness. In the cover 1 for electric heating carpet, the pile length of the warp knitted carpet material 2 is usually 4 to 6 m.
The thickness of the needle punch felt material 3 having a thickness of 2 mm is about 1.5 to 1.7 mm after the entire surface is fused.

[0029]

EXAMPLES Next, the present invention will be explained based on examples, but the present invention is not limited to the examples.

Example 1 In order to manufacture the needle punched felt material 3 of the backing material shown in FIG. 1, 45 wt% of polypropylene fiber having a fineness of 17 decitex (trade name: Toa Spin Polypro) and polyester fiber of 3.3 decitex ( Product name: Tetron) 5
5% by weight is put into a known carding machine. The polypropylene fibers used have a melting point of about 165 ° C and the polyester fibers have a melting point of about 260 ° C.

The mat 15 (FIG. 2) mixed and laminated by the carding machine described above is 170 needles / cm ² in needle density and 15 m in needle depth by an ordinary locking needle machine.
Needle punching with m to raise hair. As a result, the loop-shaped protruding fiber portion 8 is raised on the entire front surface of the felt material 16 (FIG. 3), and the protruding fiber portion has a length of about 10 mm. The felt material 16 has a thickness of 2 mm and a basis weight of 22.
It is 0 g / m ² .

On the other hand, in order to manufacture the warp knitted carpet material 2 of the surface material, the double knit material 10 (FIG. 5) is knitted from a known double Russell knitting machine, and the pile weight of the acrylic fiber yarn is 500 g / m ² . The ground weight of polyester yarn is 185
g / m ² . The double-knitted material 10 is made into two single-sided knitted fabrics 11 by center cutting, and each knitted fabric 11 has a desired pattern 12 on the pile surface by an automatic screen printing machine.
(Fig. 6) is printed.

In the laminating step shown in FIG. 4, the felt-based material 16 is cold-rolled from above (diameter 200 m).
m) It is conveyed to 18, and the felt material is fed to the roller pair 18 in a state of being turned upside down. Immediately before passing through the roller pair 18, the front side of the felt material 16 comes into contact with the open flame 7 of the burners 5 arranged in a horizontal series and melts the surface. At this time, in the felt-based material 16 (FIG. 3), the burner 5 is adjusted so that mainly the protruding fiber portion 8 and a part of the front side are melted but the back side of the felt-based material is not melted.

Further, the warp-knitted carpet material 2 allows the surface pattern 12 to be aligned in length and width through the pattern correcting device 14 (FIG. 4) before being fed to the roller pair 18, and passes through the roller pair 18 in an inverted state. The pair of rollers 18 pressurize the warp-knitted carpet material 2 and the felt-based material 16, and the front side of the felt-based material is entirely fused and integrated with the back side of the warp-knitted carpet material 2 to form the cover material 19. obtain.
The transit time of the roller pair 18 is about 0.1 minutes per meter of length.

The cover material 19 pasted on the entire surface is appropriately trimmed into a square shape, and then the periphery is sewn with an overlock sewing thread 20 as shown in FIG. If desired, the surrounding sewing thread 20 is fixed to the cloth with resin to obtain the electric carpet cover 1.

Example 2 Similar to Example 1, 45% by weight of polypropylene fiber,
55% by weight of polyester fiber of 3.3 decitex is mixed and the surface is raised to produce a felt-based material 16 having a basis weight of 220 g / m ² . Then, as in Example 1, the warp knitted carpet material 2 is entirely fused to obtain the cover material 19. However, the fineness of the polypropylene fiber used is 7.8 decitex.

Example 3 As in Example 1, 45% by weight of polypropylene fiber,
55% by weight of polyester fiber of 3.3 decitex is mixed and the surface is raised to produce a felt-based material 16 having a basis weight of 220 g / m ² . Then, as in Example 1, the warp knitted carpet material 2 is entirely fused to obtain the cover material 19. However, the fineness of the polypropylene fiber used is 5.6 decitex.

Example 4 As in Example 1, 45% by weight of polypropylene fiber,
55% by weight of polyester fiber of 3.3 decitex is mixed and the surface is raised to produce a felt-based material 16 having a basis weight of 220 g / m ² . Then, as in Example 1, the warp knitted carpet material 2 is entirely fused to obtain the cover material 19. However, the fineness of the polypropylene fiber used is 4.4 decitex.

Test Example 1 With respect to the cover materials obtained by laminating the entire surfaces obtained in Examples 1 to 4, the adhesive force to the warp knitted carpet fabric 2 due to the difference in the fineness of the polypropylene fiber which is the fiber on the low melting point side is measured. As a result, Example 1: Adhesive force 18.0 N / 5 cm width (fineness 17 decitex) Example 2: Adhesive force 12.0 N / 5 cm width (fineness 7.8 decitex) Example 3: Adhesive force 10.0 N / 5 cm Width (fineness 5.6 decitex) Example 4: Adhesive strength 8.0 N / 5 cm width (fineness 4.4 decitex)

In order to obtain a predetermined durability as the cover for the electric heating carpet, it is desirable that the adhesive strength is 10 N / 5 cm or more. From the above measurement results, 10 N / 5 cm
Adhesive strength greater than the width has a polypropylene fiber content of 45
If it is wt%, it can be achieved when the fineness is about 5.6 decitex or more.

Example 5 As in Example 1, 45% by weight of polypropylene fibers having a fineness of 12 decitex and 55% by weight of polyester fibers having a size of 3.3 decitex were mixed and the surface was raised to give a fabric weight of 220 g / m ² . The felt material 16 is manufactured. Then, as in Example 1, the warp knitted carpet material 2 is entirely fused to obtain the cover material 19.

Example 6 As in Example 5, the cover material 19 is obtained by fusing the warp-knitted carpet material 2 on the entire surface. However, the content of the polypropylene fiber used is 30% by weight.

Example 7 In the same manner as in Example 5, the warp knitted carpet material 2 is entirely fused to obtain the cover material 19. However, the content of the polypropylene fiber used is 15% by weight.

Example 8 In the same manner as in Example 5, the warp knitted carpet material 2 is entirely fused to obtain the cover material 19. However, the polypropylene fiber was not added and the polyester fiber was 100% by weight.

Test Example 2 With respect to the cover materials obtained by laminating the entire surfaces obtained in Examples 5 to 8, the adhesive force to the warp knitted carpet fabric 2 due to the difference in the content of the polypropylene fiber which is the fiber on the low melting point side is measured.
As a result, Example 5: Adhesive strength 15.0 N / 5 cm width (content 45% by weight) Example 6: Adhesive strength 10.0 N / 5 cm width (content 30% by weight) Example 7: Adhesive strength 7.2 N / 5 cm width (content 15% by weight) Example 8: adhesive strength 7.0 N / 5 cm width (content 0% by weight)

From the above measurement results, the adhesive force of 10 N / 5 cm width or more can be achieved when the content is 30% by weight in the case of polypropylene fiber having a fineness of 12 decitex. In this case, the fineness of polypropylene fiber is 17-
Since it is possible in the range of 30 decitex, an adhesive force of 10 N / 5 cm width or more can be obtained when the content is about 10% by weight or more.

[0047]

The cover for electric heating carpet according to the present invention is relatively thin and light by directly fusing the backing material to the surface material, so that the purchaser of the product can wash it at any time at home, and it can be washed by a fully automatic washing machine. Is also fully possible. This electric heating carpet cover has good durability even though it is relatively thin, and transmits heat from the carpet body well to the front side of the surface material,
Moreover, since the urethane layer is not deteriorated, worn or damaged, it can be used for a long time.

In the cover for an electric heating carpet of the present invention, if the surface material is a warp knitted carpet material, a surface pattern having a free design can be formed by a printing process. In addition, since the entire cover for this electric heating carpet is composed of synthetic or natural fibers, it can be re-sewn as fluff etc. at the time of disposal after use, and does not generate toxic gas even if it is incinerated, thus polluting the environment. The problem of can be avoided.

In the cover manufacturing method according to the present invention, the urethane layer and the adhesive layer are not interposed between the surface material and the back surface material,
The cover can be rapidly manufactured by directly fusing the surface material and the back surface material. When the back surface material is a felt material, the front side of the felt material is napped by needle punching, and the fluffed felt surface side is melted and bonded to the surface material, whereby a strong whole surface fusion can be achieved.

[Brief description of drawings]

FIG. 1 is a schematic side view of a cover for an electric heating carpet according to the present invention.

FIG. 2 is a schematic side view showing an enlarged mat serving as a felt material.

FIG. 3 is an enlarged schematic side view showing a napped felt-based material.

FIG. 4 is a schematic explanatory view showing a step of laminating a carpet cover.

FIG. 5 is a schematic side view showing a double-knit material as a warp-knit carpet material.

FIG. 6 is a schematic plan view showing an example of a cover for an electric heating carpet.

[Explanation of symbols]

1 Cover for electric heating carpet 2 Warp knitting carpet 3 Needle punch felt material 5 heating burner 8 protruding fiber part 12 surface design 14 Design correction device 18 roller pair

Claims (6)

[Claims] 1. A back surface comprising a surface material that is in direct contact with a user and a cushioning back surface material that is close to an electric heating body, and a protruding fiber portion is raised on the entire front surface of the back surface material, and the back surface including the protruding fiber portion. A cover for an electric heating carpet in which the backside material is entirely fused to the backside of the surface material mainly on the basis of the protruding fiber portions by heat-melting and pressurizing the front side of the material. 2. A surface material is a warp knitted carpet material, a tufted carpet material, a Wilton carpet material, a fiber mat material, a tatami mat, a mat, a synthetic resin sheet or a cushion floor sheet, and a back material is a needle punch felt material or felt. The cover according to claim 1, which is a felt-based material such as a composite material of a base material. 3. The backing material is made of a felt-based material in which at least two kinds of fibers having different melting points are mixed and has a melting point of 17
The cover according to claim 1 or 2, wherein the fibers on the low melting point side having a temperature of 0 ° C or lower have a fineness of about 5.6 dtex or more, and about 10% by weight or more of the total amount is added. 4. The surface of either the back side of a pile-like surface material that is in direct contact with the user or the front side of a cushioning back surface material that is close to the electrothermal body is surface-melted and the surface is immediately melted while maintaining the molten state. A method for producing a cover for an electric heating carpet, in which a backing material and a backing material are cold-bonded to each other and the backing material is directly fused to the back side of the fronting material. 5. A felt-based material is used as a cushioning backing material close to the electrothermal body, and the entire front surface of the felt-based material is napped by needle punching, and the fluffed material front surface is melted to maintain a molten state. as it is,
A method of manufacturing a cover for an electric heating carpet, which is immediately laminated with a pile-like surface material and the back surface material is directly fused to the back surface of the surface material. 6. When running a pile-like surface material that is in direct contact with a user, the surface pattern is arranged vertically and horizontally through a pattern correcting device, and then either the back side of the surface material or the front side of the cushioning back surface material. A method for producing a cover for an electric heating carpet in which a surface material and a back material are immediately cold-bonded to each other while the surface is melted and the molten state is maintained, and the back material is directly fused to the back side of the surface material.