JPH0871268A - Cushion molding and manufacture thereof - Google Patents

Abstract

PURPOSE: To provide a cushion molding improving productivity, ensuring the gas shielding function at a sewn section, and excellent in external appearance and touch. CONSTITUTION: This cushion molding 1 is integrally molded with a foam resin in a skin material, a tape 5 made of a thin film is thermally fused to the needle thread side of a sewn section by double ring sewing, no foam resin 6 is infiltrated into seams by the foam pressure at the time of foam molding on the bobbin thread side due to this seam structure, and no synthetic resin is seeped and solidified on the outer face from the sewn section. The sewn section is not made rigid, the external appearance becomes excellent, the heat fusion tape 5 is easy to handle, it is merely heated and fused along the seams on the needle thread side on one face, not the whole sewn section, thus manufacturing man- hours are reduced, the complexity of the work is resolved, and the productivity is remarkably improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cushions used in various vehicles such as seats, headrests, door trims, etc., or cushions such as various household buffers, and a method for manufacturing the same, and more particularly to a skin material. TECHNICAL FIELD The present invention relates to various cushion molded bodies formed by integrally molding a synthetic resin foam body inside thereof and a manufacturing method thereof.

[0002]

2. Description of the Related Art A bag made by cutting a cloth such as a woven knitted fabric, a non-woven fabric or the like whose outer surface is coated with a synthetic resin and synthetic leather, natural leather or the like into a predetermined shape and then sewing the cut cloth. It is widely known that a cushion molded body having a desired shape is manufactured by forming a body and injecting a synthetic resin foam material into the bag body to foam the body.

By simply cutting and sewing the above-mentioned skin material, a high pressure due to foaming is generated inside the bag during foam molding of the synthetic resin, the seam is opened and the needle hole is enlarged. Part of the foamed resin leaches to the surface of the seam and solidifies, which not only impairs the appearance but also makes the periphery of the sewn portion rigid.

In order to solve these problems, many proposals have been made in the past to prevent the synthetic resin from leaching from the seams. For example, in Japanese Examined Patent Publication No. 3-56076, liquid-containing treatment is performed by spraying a liquid such as water around the seams in advance during the foam molding. By doing so, the seams are temporarily closed by the liquid at the time of molding and the infiltration of the foamed resin is prevented. Further, in Japanese Examined Patent Publication No. 5-83053, a thickness of 15 to 80 is attached to a seam on the gas shield layer side of the epidermis.
A method of adhering an adhesive tape made of a polyurethane film of μ including a seam allowance is disclosed.

[0005]

However, there is no guarantee that the seam will be completely closed only by the liquid-containing treatment disclosed in Japanese Patent Publication No. 3-56076 mentioned above, and therefore the liquid-containing treatment is performed in the embodiment of the publication. Prior to the above, paper, water-absorbent fibers, etc. are sewn into the sutured portion at the same time in advance to ensure that the needle hole is closed due to the liquid-containing treatment. Therefore, in order to secure the method of closing the seam disclosed in the publication, complicated processing steps are added, which affects the production efficiency.

Further, according to the gas shielding means for the sutured portion disclosed in Japanese Patent Publication No. 5-83053, the both sides of the gas shielded side of the sutured portion are adhered and covered with the adhesive tape. Not only is the work complicated, but it is necessary to make some efforts in handling the adhesive tape.

The present invention has been made in order to solve the above-mentioned conventional problems, and its purpose is to improve the workability, to secure the gas shielding function in the suture portion, and to have an excellent appearance and feel. It is intended to provide a cushion molded body.

[0008]

The above object is to foam the inside of a bag body obtained by cutting and stitching a surface material such as cloth having a gas shielding function, synthetic leather, natural leather, etc., into a predetermined shape according to the first aspect of the invention. A cushion molded body formed by integrally molding a resin body, wherein the suture is made by double chain stitching, and a gas shielding film is formed only along an upper thread line exposed on one side of the seam portion. Is achieved by the cushion molded body.

Preferably, the foamed resin body is a polyurethane foam body, and the gas shielding film is a film formed by sticking and integrating a heat-welding tape made of a polyurethane or vinyl chloride resin by heating. Of course, the material of the gas shielding film can be changed depending on the material of the foamed resin body, and it is desirable that both materials have affinity for each other.

Further, such a cushion molded body is a bag body having a predetermined shape by cutting and stitching a surface material such as a cloth having a gas shielding function, synthetic leather or natural leather according to the second aspect of the invention. A method for producing a cushion molded body by injecting and foaming a synthetic resin foam material into the inside of, to form a cushion molding, wherein after the suturing is performed by a double chain stitch sewing machine, a suture is drawn along one side of the sutured portion. The heat-welding tape is attached only to the above to heat-integrate by heating. Further, preferably, a pinhole is formed in the tape welding portion of the suture portion before the heat welding tape is welded.

[0011]

In the seam formed by the double chain stitch of the present invention, the stitch formed by the bobbin thread keeps the needle hole on the bobbin thread side completely closed by the loop formed for each stitch. The foamed resin material inside does not seep through the seams (needle stitches) to the bag surface. On the other hand, the seam on the needle thread side is the same as the normal lock stitch, so especially on the needle thread side of the skin material that has been made rigid by coating the back surface, the needle thread is not blocked by the needle thread and the bag body When the synthetic resin material is injected and foamed in accordance with the usual method, the synthetic resin material is leached from the lower thread side to the bag surface through the stitches (needle stitches) due to the foaming pressure.

Therefore, only the stitches (needle stitches) on the upper thread side are welded and closed by the heat-welding tape. This heat-welding tape is as easy to handle as a normal tape and can be reliably integrated with the bag,
In addition, it can completely close the stitches and contribute to the improvement of production efficiency.

By doing so, the foamed resin is completely prevented from entering the seam on the upper thread side by the heat-welding tape, and at the same time, does not penetrate into the seam on the lower thread side where the tape does not exist. In any case, the foamed resin does not seep into the surface of the seam of the bag body, the appearance of the cushion molded body is not impaired, and the seam of the skin material does not become rigid, which makes the user feel uncomfortable. Absent.

If a pinhole is formed in advance in the seam allowance portion which is the welded portion of the heat-welding tape after the step of cutting the skin material and before or after the step of sewing,
During welding of the heat-welding tape, part of the molten resin on the surface of the tape penetrates into the pinholes and solidifies, causing the so-called anchor effect, and the tape is firmly welded to the back surface of the skin material. Even if the cushion molded body is used for a long period of time, peeling does not occur between the foamed resin inside and the skin material at the sewn portion, and the shape retention of the cushion molded body is secured.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on illustrated embodiments. 1 (a) and 1 (b) show the upper thread side stitching surface and the lower thread side stitching surface of the bag body applied to the present invention, and FIG. 2 is the welding of the heat-welding tape to the stitched portion according to the present invention. FIG. 3 shows an example of the welding mechanism of the tape.

In the present embodiment, the cushion molded body 1 is a headrest having a shape as shown in FIG. 4, and a single-sided woven fabric is used as the material of the skin material 2. In addition to the headrest, the cushion molded body 1 according to the present invention includes various cushioning bodies such as seats and door trims in automobiles, sofas and beds used in homes,
Examples include various cushions such as cushions and chairs. The material of the skin material 2 is not limited to the above-mentioned raised fabric, and for example, ordinary knitted fabric, raised knitted fabric, non-woven fabric, or synthetic leather or natural leather is used. When the cloth is used as the skin material 2, the skin material 2 is used in order to prevent the leakage of gas generated during the subsequent injection and foaming of the synthetic resin.
A gas blocking process is performed on the back surface of the. Usually, this gas blocking treatment is performed by coating a synthetic resin with a thickness that does not cause air permeability.

Also in this embodiment, the synthetic resin material is injected and foamed following the steps of cutting the skin material 2 into a predetermined shape and then stitching it to form a bag and the step of welding the heat-welding tape. The process is almost the same as the conventional process, but in the sewing process, the double chain stitch sewing machine is used in the present invention, and the seam is formed by the double chain stitch consisting of the upper thread 3 and the lower thread 4 as shown in FIG. To be done. As described above, the reason why the present invention limits the seam by the double chain stitch is that the stitches by the bobbin thread form a loop for each stitch, so that the needle hole on the bobbin thread side is completely closed by the loop of the bobbin thread. This is because it was found that the condition would be met. On the other hand, in such a double chain stitch, the stitches on the needle thread side are the same as those of the normal lock stitch, so that the needle thread 3 is especially sewn on the needle thread side of the skin material 2 which is made rigid by coating the back surface. It was also found that the needle holes were often not blocked by the method. Then, when a synthetic resin material is injected and foamed in the bag thus obtained according to a conventional method, the synthetic resin material does not seep from the bobbin thread side to the bag surface through stitches (needle stitches),
From the stitches on the upper thread side, it was learned that the synthetic resin material seeps into the bag surface due to foaming pressure.

Therefore, the inventors of the present invention are convinced that if only the stitches (needle stitches) on the upper thread side are closed by some means, the synthetic resin material will not seep to the surface of the bag during foam molding. Came to do. Next, when we examined what kind of means to use as the closing means, it was usually easy to handle as with ordinary tape, and it was surely integrated with the bag body, and the needle eye was completely closed. It was concluded that the adoption of a heat-sealable tape is also effective from the viewpoint of improving production efficiency.

As a material for such a heat-fusible tape, a film made of a synthetic resin material having an affinity for the foamed resin material at the time of subsequent foam molding is usually coated with a heat-meltable synthetic resin. . As the material of the synthetic resin film, a resin material of the same type as the foamed resin material is used, and typically, a polyurethane film or a polyvinyl chloride film can be mentioned. As the heat-meltable resin material coated on one surface of the film, a synthetic resin material of the same material as the film is used.

In this embodiment, "MELCO ^™ FU700" (manufactured by Sun Kasei Co., Ltd.) is used as the heat-welding tape.
Are using. This heat-welding tape is a polyurethane film whose surface is similarly coated with a polyurethane resin. The tape has a thickness of 0.055 mm and a tape width of 20 mm. Further, a vinyl chloride film coated with a polyurethane resin may be used as the heat-welding tape. Tape thickness is 0.5
mm to 0.09 mm is desirable. Of course, when the film itself has a melting property at a predetermined temperature, the film alone may form a heat-welding tape.

The heat-welding tape 5 constructed as described above.
2 is welded along the seam on the upper thread side of the bag body which is turned upside down as shown in FIG. 2, therefore, in this embodiment, a hot air type heat sealer (QHP manufactured by Quinlite Electronic Seiko Co., Ltd.) is used.
-778L) is used. FIG. 3 shows the mechanism of the sealer in a simplified manner.
The heat-welding tape 5 is pulled out from the tape roll 11 rotatably supported by the guide rolls 12 through the plurality of guide rolls 12 while the tension is adjusted by the dancer rolls 13. As described above, it is introduced between the upper pressing roll 16 and the lower heating roll 17. A bag body is set on the lower heating roll 17 with the stitched portion as an upper surface and turned upside down to form a welded body. At this time, the seam of the upper thread 3 is opposed to the welding surface of the heat-welding tape 5 introduced between the upper pressing roll 16 and the lower heating roll 17 in the sewn portion.

Now, as described above, the welding surface of the heat-sealable tape 5 introduced between the upper pressing roll 16 and the lower heating roll 17 is sequentially melted, and is set there and is set by both rolls 16 and 17. The bags are integrated by pressure welding along the seams on the upper thread side that are sequentially fed out. The sealer is equipped with a cutting device for the heat-welding tape 5, and when the welding of a predetermined portion is completed, the cutting device is operated automatically or by an operation to cut the tape 5.

The bag body thus formed is set in a molding die, and a foaming resin is injected into the bag body according to a conventional method to carry out foam molding to form a headrest 1 having a shape as shown in FIG. . FIG. 5 is an enlarged model view showing the form of the sutured portion by cutting off a part of the headrest 1. According to the figure, it is obvious that the foamed resin 6 is completely prevented from entering the stitches on the upper thread side by the heat-welding tape 5, and at the same time, it does not penetrate into the stitches on the lower thread side where the tape 5 does not exist. In any case, the foamed resin 6 does not seep to the surface of the sewn portion of the bag body, so that the appearance of the headrest 1 is not impaired, and the sewn portion of the skin material 2 is not stiffened by people, resulting in an uncomfortable feeling. I do not feel.

FIG. 6 shows another embodiment of the present invention. According to the figure, the heat-welding tape 5 is formed after the step of cutting the skin material 2 and before or after the stitching step. The pin pole 7 is formed in advance at the seam allowance portion, which is the welded portion of. By forming the pinholes 7 in this way, when the heat-welding tape 5 is welded, a part of the molten resin on the tape surface penetrates into the pinholes 7 and solidifies, so that a so-called anchor effect occurs. Since the tape 5 is firmly welded to the back surface of the skin material 2, peeling occurs between the foamed resin inside and the skin material 2 in the sewn portion even when the cushion molded body 1 is used for a long period of time. Without doing so, the shape retention of the cushion molded body is ensured.

[0025]

As is clear from the above description, the cushion molded body in which the foamed resin is integrally molded inside the skin material of the present invention is composed of a thin film on the upper thread side of the stitched portion by double chain stitching. By simply heat-sealing the tape, the foamed resin does not leach from the sewn portion to the outer surface and solidify due to the foaming pressure during foam molding, so the sewn portion does not become rigid and also has an excellent appearance Becomes Further, the manufacturing method also uses a heat-welding tape as a means for closing the seam of the stitched portion, so that it is easy to handle, and when welding the tape, the stitch of the stitched portion is double chain stitch, In addition, the tape is not welded to the entire sewn part, but is simply heated and welded along the seam on the upper thread side, which is one side of the sewn part, reducing the number of manufacturing steps and eliminating the complexity of work. Therefore, the production efficiency is remarkably improved.

[Brief description of drawings]

FIG. 1 is a plan view showing a seam structure of a skin material according to the present invention.

FIG. 2 is a plan view showing a welded state of the heat-welding tape on the sutured portion.

FIG. 3 is a side view schematically showing an example of a welding mechanism of the heat-welding tape.

FIG. 4 is an external view showing a headrest, which is an example of a cushion molded body of the present invention, by cutting out a part thereof.

FIG. 5 is an explanatory view of the form of a suture portion showing the interior of the cushion molded body in an enlarged manner.

FIG. 6 is a plan view showing another embodiment of the suture section.

[Explanation of symbols]

 1 Headrest (Cushion Molded Body) 2 Skin Material 3 Upper Thread 4 Lower Thread 5 Thermal Adhesive Tape 6 Foam Resin 7 Pinhole 10 Bracket 11 Tape Roll 12 Guide Roll 13 Dancer Roll 14 Tape Guide 15 Hot Air Blowing Passage 16 Top Pressing Roll 17 Lower heating roll

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[Procedure amendment]

[Submission date] September 13, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0024

[Correction method] Change

[Correction content]

FIG. 6 shows another embodiment of the present invention. According to the figure, the heat-welding tape 5 is formed after the step of cutting the skin material 2 and before or after the stitching step. in which previously formed pin halls 7 to seam allowance portion which is welded part of. By forming the pinholes 7 in this way, when the heat-welding tape 5 is welded, a part of the molten resin on the tape surface penetrates into the pinholes 7 and solidifies, so that a so-called anchor effect occurs. Since the tape 5 is firmly welded to the back surface of the skin material 2, peeling occurs between the foamed resin inside and the skin material 2 in the sewn portion even when the cushion molded body 1 is used for a long period of time. Without doing so, the shape retention of the cushion molded body is ensured.

Claims (4)

[Claims] 1. A cloth having a gas shielding function, synthetic leather,
A cushion molded body obtained by integrally molding a foamed resin body inside a bag body obtained by cutting and stitching a surface material such as natural leather into a predetermined shape, wherein the stitching is performed by double chain stitching,
A cushion molded body, characterized in that a gas shielding film is formed only along an upper thread line exposed on one side of the sewn portion. 2. The foamed resin body is a polyurethane foam body, and the gas shielding film is a film formed by integrally bonding a heat-welding tape made of a polyurethane-based or vinyl chloride-based resin by heating. Cushion molding. 3. A cloth having a gas shielding function, synthetic leather,
A method for producing a cushion molded body by cutting and stitching a skin material such as natural leather to form a bag body having a predetermined shape, and injecting and foaming a synthetic resin foam material into the bag body, wherein the stitching is performed. A cushion molded body characterized by being welded and integrated by heating while attaching a heat-welding tape only along the upper thread line that appears on one surface of the seam after being made by a double chain stitch sewing machine. Production method. 4. Prior to the welding of the heat-welding tape,
The manufacturing method according to claim 3, wherein a pinhole is formed in the tape welding portion of the sewn portion.