JP2001061607A - Cushion body and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cushion body in which cushion and covering materials can be easily disintegrated. SOLUTION: This cushion body 1 has a network cushion material 3 having three dimensional random loop network structure, and a covering material 4 covering the cushion material 3. Pulling-over groove 10 is formed in the network cushion material 3. A first wire 15 is inserted from the side of the cushion material 3 to the desired position along the hanging groove 10. The first wire 15 does not stick to a continuous linear body 2 forming the network cushion material 3 and is so formed that it can be pulled out from the cushion material 3 in the case of disintegration. A pulling-over bag 23 is sewn on to the pulling- over portion 4a of the skin material 4 and a second wire 25 is housed in the pulling-over bag 23. The first wire 15 and the second wire 25 are connected by a hog ring 27.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cushion body suitable for seats mounted on vehicles such as vehicles, ships, and aircraft, or furniture such as sofas and beds, and a method of manufacturing the same.

[0002]

2. Description of the Related Art For example, a cushion member made of a resin foam such as urethane foam has been widely used as a cushion body used for, for example, a vehicle seat. Also,
It has also been practiced to fix a skin material covering the outside of the cushion material with an annular connecting member called a hog ring. When the skin material is fixed by hog ring, the first wire is buried in the resin foam, a hanging bag is sewn on the back side of the hanging portion of the skin material, and the second wire is inserted into the hanging bag. . Then, inside the suspension groove formed in the cushion material, an operation of connecting the first wire and the second wire to each other by a hog ring is performed.

In the case of a cushioning material using a resin foam such as urethane foam, the first wire is set in a mold for molding the resin foam, and this wire is integrated with the resin foam as the resin foam is foamed. Become For this reason, the resin foam and the wire embedded in the resin foam are in a state of being strongly bonded to each other by the bonding force of the resin.

[0004]

In order to recycle the cushion material, it is necessary to separate the skin material and the wire from the cushion material (resin foam). For this reason, the hog ring is cut by a tool to separate the skin material from the cushion material. Although the second wire contained in the hanging bag of the skin material can be easily pulled out, the first wire embedded in the resin foam is strongly bonded to the resin foam, so that the second wire is firmly adhered to the resin foam. It is extremely difficult to separate the wire from the resin foam,
The dismantling work required a great deal of time and money, and it was practically difficult to recycle.

[0005] Instead of using the hog ring, it is conceivable to fix the skin material to the cushioning material with a detachable flat fastener such as Velcro tape, but this flat fastener is attached to a predetermined position of each of the cushioning material and the skin material. There is also a problem that the work is troublesome and the cost is high.

Accordingly, it is an object of the present invention to provide a cushion body, a cushion body, a skin material, and a hanging wire which can be easily disassembled and which can be recycled, and a method of manufacturing the cushion body.

[0007]

In order to achieve the above object, a cushion body according to the present invention has a three-dimensional net-like structure or a cotton-like fiber structure composed of a plurality of linear bodies adhered to each other and has a surface side. A cushioning member having a suspension groove formed therein, and a first plug-in member which is inserted along a suspension groove of the cushioning material from a side surface of the cushioning material to a predetermined position and is not bonded to the linear body. And a skin material that covers the cushion material and has a second wire provided in a suspension portion corresponding to the suspension groove,
A connector for connecting the first wire and the second wire to each other in the suspension groove of the cushion material; The first wire and the second wire may be made of metal, but may be made of synthetic resin in some cases.

When the cushion body of the present invention is disassembled for recycling, the skin material is separated from the cushion material by pulling out the first wire from the cushion material or cutting the connecting member. Since the first wire is a plug-in wire that is not bonded to the linear member of the cushion material, the first wire can be easily pulled out of the cushion material. The second wire can be easily pulled out from a hanging bag or the like.

According to the present invention, an opening for exposing a part of the first wire is formed at the bottom of the suspension groove of the cushion material, and the first wire is suspended from the opening at an intermediate portion in a longitudinal direction of the first wire. Forming a protruding portion in the groove. This convex portion is connected to the second wire by a connecting tool such as a hog ring. In this case, a window for exposing a part of the second wire may be formed in the hanging bag of the skin material.

The invention includes forming a loop at the end of the first wire. The method also includes setting the inner diameter of the hog ring to a size that allows the protrusion of the first wire and the loop to pass through. This allows
The first wire can be pulled out of the cushion material without cutting the hog ring.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 A cushion body 1 shown in FIG. 1 is used for a seat or a backrest of a seat of an automobile or the like. FIG. 2 shows a part of the cross section of the cushion body 1.
Shown in This cushion body 1 has a three-dimensional net-like structure in which a continuous linear body 2 of 300 denier or more mainly made of a thermoplastic elastic resin is meandered in a random loop shape and the contact portions of the loops are fused to each other. And a skin material 4 covering the front side of the mesh cushion material 3 and the like. An example of the wire diameter of the continuous linear body 2 is φ1 mm.

As shown in FIG. 3, a suspension groove 10 is formed on the front side of the mesh cushion material 3. The suspension groove 10 extends substantially linearly in the front-rear direction or the width direction of the mesh cushion material 3. As shown in FIGS. 4 and 5, openings 11 are formed in the bottom 10 a of the suspension groove 10 at intervals at a plurality of positions in the longitudinal direction of the groove 10.

A first wire 15 is inserted into the mesh-like cushion material 3 along the suspension groove 10 to a predetermined position of the cushion material 3. The wire 15 is inserted into the cushion member 3 from the side surface 3c of the cushion member 3. That is, the first wire 15 is a plug-in wire, and this wire 15 is not bonded to the continuous linear body 2 of the cushion material 3.

A plurality of projections 16 are formed at a plurality of locations at a predetermined interval in the longitudinal middle portion of the first wire 15. These projections 16 are provided in each opening 1 of the suspension groove 10.
1 is formed at a pitch corresponding to the first wire 1
When the plug 5 is inserted to the predetermined position, each convex portion 16 projects from the opening 11 into the hanging groove 10. Loops 17 are formed at both ends of the first wire 15. FIG. 6 shows a part of the opening 11 and the projection 16 in an enlarged manner.

As shown in FIG. 2, the skin material 4 includes a skin 20 made of woven fabric or leather, a wadding made of thin urethane foam or a cushioning material 21 made of a fine fiber layer having a small wire diameter, and a backing. It is made of base cloth 22 and the like,
It is cut in advance into a shape that can be covered. The suspension groove 4 is provided in the suspension portion 4 a located on the back side of the skin material 4.
The hanging bag 23 is sewn along 0.
The hanging bag 23 is housed in the hanging groove 10.

A second wire 25 is accommodated in the hanging bag 23. As shown in FIG. 7, a window 26 is formed in the hanging bag 23 so that a part of the second wire 25 (a portion where a hog ring 27 described later is hooked) is exposed. The window 26 is formed at a position corresponding to the opening 11 of the suspension groove 10. The first wire 15 seen from the opening 11 of the hanging groove 10 and the second wire 25 seen from the window 26 of the hanging bag 23 are connected to each other by a hog ring 27 as an example of a connecting tool.
Each of the first wire 15 and the second wire 25 is generally a metal wire, but may be a non-metal wire made of a thermoplastic resin or the like in some cases.

If the apparent density of the net-like cushion material 3 is less than 0.005 g / cm ³ , the resilience is lost, so that it is not suitable as a cushion body. The apparent density is 0.
If it exceeds 2 g / cm ³ , the resilience becomes too strong and the sitting comfort becomes poor, so that it is also unsuitable as a cushion body. More preferred apparent density 0.01 g / cm ³ or more and 0.05 g / cm ³ or less.

On the other hand, if the fineness of the continuous linear body 2 is less than 300 denier, the strength is reduced and the repulsive force is reduced, which is not preferable. If the fineness exceeds 100,000 denier, the number of the continuous linear bodies 2 per unit volume decreases, and the compression characteristics deteriorate. That is, it is 300 denier or more, and preferably 400 denier or more and 100,000 denier or less, and more preferably 500 to 50,000, at which a preferable repulsion force is obtained as a cushion body.
Denier.

As the thermoplastic elastic resin which is the material of the continuous linear body 2, a polyester elastomer, a polyamide elastomer, a polyurethane elastomer, or the like can be used. The polyester elastomer is, for example, a polyester ether block copolymer having a thermoplastic polyester as a hard segment and a polyalkylene diol as a soft segment, or a polyester ether block copolymer having an aliphatic polyester as a soft segment. Examples of the polyamide-based elastomer include those having a hard segment of nylon and a soft segment of polyethylene glycol or polypropylene glycol.

The thermoplastic elastic resin may be combined with a thermoplastic inelastic resin. The thermoplastic inelastic resin is, for example, polyester, polyamide, polyurethane or the like. The combination of the inelastic resin and the thermoplastic elastic resin is preferably a resin of the same type from the viewpoint of recycling use, for example, a combination of a polyester elastomer and a polyester resin, or a polyamide elastomer and a polyamide resin. Or a combination of a polyurethane-based elastomer and a polyurethane-based resin is recommended.

The mesh cushion material 3 is manufactured by a mesh cushion manufacturing apparatus 30 conceptually shown in FIG. One example of the net-like cushion material manufacturing apparatus 30 is an extruder 3
5 and a nozzle portion 36. The extruder 35 extrudes the thermoplastic elastic resin raw material supplied from the material supply port 37 toward the nozzle portion 36 while heating the raw material to a temperature higher by 10 ° C. to 80 ° C. (for example, 40 ° C. higher) than its melting point. .

The thermoplastic elastic resin heated to the above-mentioned temperature is discharged downward from the nozzle portion 36 and continuously drops linearly without interruption. If the melting temperature of the thermoplastic elastic resin at the time of discharge is set to a temperature higher by 30 ° C. to 50 ° C. than the melting point of the resin, a random three-dimensional loop is easily formed, and the contact portions between the loops are fused to each other. This is preferable because it can be kept in an easy state.

The nozzle portion 36 has a nozzle effective surface 3 having a predetermined size.
In this nozzle effective surface 38, a large number of nozzles 36a having a hole diameter of about 0.5 mm are provided at a predetermined pitch between holes (for example, pitch: 5 mm). The extruder 35 discharges the thermoplastic elastic resin from the nozzle 36a so that the discharge amount per nozzle is 0.5 g to 1.5 g / min. The nozzle effective surface 38 is provided only in a region corresponding to the cross-sectional shape of the mesh cushion material 3 to be formed.
6a may be opened. Below the nozzle portion 36, a liquid surface 40a of a cooling liquid 40 such as water that functions as a cooling unit is located. The cooling liquid 40 is heated, for example, to a temperature of about 70 ° C.

A guide means 41 is provided below the nozzle section 36. The guide means 41 includes the mesh cushion material 3
A pair of endless belts 42 and 43 made of a metal net made of, for example, stainless steel and provided with upper and lower rollers 44 and 45 are provided so as to face both surfaces 3a and 3b in the thickness direction. The upper part of each belt 42, 43 is provided with a cooling liquid 40.
Is exposed on the liquid surface 40a. These belts 42,
Reference numeral 43 denotes a drive mechanism that uses a motor or the like as a drive source, and continuously runs endlessly between rollers 44 and 45.

The mesh cushion material 3 having a three-dimensional random loop network structure manufactured by the cushion material manufacturing apparatus 30 is cut into a desired shape by, for example, a cutting machine equipped with a heater wire. As the cutting means, besides using the heater wire, cutting by water jet, cutting by a press die, or cutting by a rotating disk-shaped blade (so-called vertical cutter) may be used. Alternatively, the mesh cushion material 3 may be formed into a desired shape under heat and pressure by hot pressing using a forming die.

Next, the steps of manufacturing the cushion body 1 will be described. The thermoplastic elastic resin material is supplied to the extruder 35 of the mesh cushion material manufacturing apparatus 30, the resin material is heated and softened, and the molten thermoplastic elastic resin material is supplied to the nozzle 3.
6a, the ink is spontaneously dropped between the belts 42, 43. When the melted thermoplastic elastic resin falls between the belts 42 and 43, the continuous linear bodies 2 corresponding to the number of the nozzles 36a are formed, and are sandwiched and stopped between the belts 42 and 43. A random loop occurs while winding. Each of these continuous linear bodies 2 is formed in a direction intersecting with the direction A (for example, the direction of the arrow B) while continuing in the direction of the arrow A in FIG.

By setting the pitch of the nozzles 36a so as to allow the loops to contact each other, the loops are brought into contact with each other between the belts 42 and 43, and the contact portions between the loops are fused to form a net having a three-dimensional net structure. The cushion material 3 is obtained. By maintaining the temperature of the cooling liquid 40 at the annealing temperature of the continuous linear body 2 (pseudo-crystallization acceleration temperature), the pseudo-crystallization treatment can proceed simultaneously.

The mesh cushion material 3 to which the loop has been fused is
The two sides 3a, 3b in the thickness direction are drawn into the coolant 40 while being regulated by the belts 42, 43, and the coolant 4
At the same time as the hardening is performed within 0, the fused portion of each loop is fixed. The mesh-shaped cushion material 3 is formed by continuously connecting a number of continuous linear bodies 2 corresponding to the number of nozzles 36a while drawing a random loop. The cushion material 3 is formed into a desired shape by cutting or hot pressing. The above is the cushion material forming step.

Further, a suspension groove 10 is formed in the cushion material 3. The suspension groove 10 is formed by a mold (not shown) corresponding to the suspension groove 10. This mold has a built-in heater and is heated to a temperature higher than the softening temperature of the continuous linear body 2. The mold is pressed against the mesh cushion material 3 to form a hanging groove 10 having a width of, for example, 10 mm and a depth of 25 mm, and an opening 11 having a depth of about 10 mm from the bottom 10 a of the hanging groove 10.

After that, the first wire 15 having a wire diameter of, for example, φ1.8 mm is placed along the suspension groove 10 so that the depth from the bottom 10 a of the suspension groove 10 becomes about 10 mm. Of the first wire 15 and the protrusion 1 of the first wire 15 and the opening 1 of the hanging groove 10.
Expose at 1. Since the mesh-like cushion material 3 is constituted by the continuous linear body 2 of a three-dimensional random loop having a relatively coarse three-dimensional mesh structure, the first wire 1
5 can be inserted relatively easily to the desired position.

On the other hand, the second wire 25 is inserted into the hanging bag 23 sewn to the hanging portion 4a of the skin material 4. Then, the protrusion 16 of the first wire 15 visible in the opening 11 inside the suspension groove 10 and the second wire 25 visible in the window 26 of the suspension bag 23 are connected to each other by a hog ring 27. The hog ring 27 is caulked annularly using a tool such as a hog ring gun. Thus, the skin material 4
Is fixed to the mesh cushion material 3.

The reticulated cushion material 3 is formed by winding a continuous linear body 2 of 300 denier or more made of a thermoplastic elastic resin to form a large number of random three-dimensional loops, and the respective loops are brought into contact with each other in a molten state. Most of the contact portions are fused to each other to form a three-dimensional random loop-shaped net-like structure. Therefore, even when a large deformation is given by a large stress, the cushion material 3 absorbs the stress while deforming three-dimensionally with each other, and when the stress is released, the cushion material 3 is formed by the rubber elasticity of the thermoplastic elastic resin. The original shape can be restored. Moreover, since the continuous linear bodies 2 are fused to each other in a molten state, the cushion material 3 does not require a binder, and is made of a single thermoplastic resin, so that it can be easily recycled by re-melting.

When the cushion body 1 is recycled, the hog ring 27 is cut by a tool, and the skin material 4 is separated from the mesh cushion material 3. Then, the first wire 15 is pulled out of the mesh cushion material 3. in this case,
Since the loop 17 is formed at the end of the wire 15,
The wire 15 can be pulled out relatively easily by grasping and pulling the loop 17 with a finger. Further, the second wire 25 is taken out from the hanging bag 23. Thus, the first wire 15 and the second wire 25 could be disassembled in a short time (about 1.5 minutes).

The mesh cushion material 3 in which the skin material 4 and the wires 15 and 25 are separated may be cut into chips, for example.
It can be made into fine powder and reused as a material recycling material. Since the wires 15 and 25 separated from the mesh cushion material 3 have no thermosetting resin such as urethane, they can be recycled as metal resources.

[Embodiment 2] The constructions of the skin material and the cushion material are the same as those of the embodiment 1, but the inner diameter R of the hog ring 27 after caulking is changed to the height H of the projection 16 as shown in FIG.
(For example, 6 mm) and larger than the outer dimension D of the loop 17 so that the projection 16 and the loop 17 can pass through the hog ring 27.
One example of R is 7 mm. In this case, the first wire 15 can be pulled out from the mesh cushion material without cutting the hog ring 27 at the time of recycling, so that the time required for disassembly is further reduced, and disassembly was possible in about one minute.

Example 3 Polyester (6 denier,
A binder fiber (6 denier, melting point: 110 ° C.) made of a thermoplastic resin having a low melting point is blended and defatted at a weight ratio of 7: 3 to a main fiber made of a hollow conjugate, and a sheet having a thickness of 20 mm is formed. I made it. The main fiber is
It is an example of the linear body in the present invention. The sheet-like cotton was cut into a predetermined shape, laminated, and placed in a mold so as to have a predetermined density. Thereafter, the binder fiber was melted with hot air having a temperature equal to or higher than the melting point of the binder fiber, and was welded to the main fiber. By hardening the binder resin by cooling, the entanglement points of the main fibers are bonded by the binder resin, and the mold is released, so that the fibrous cushion material 50 made of an aggregate of the cotton-like main fibers 49 as shown in FIG. I got

The first wire 5 is attached to the cushion material 50.
1 is a cushion material 5 similar to the wire 15 of the first embodiment.
0 to the predetermined position along the hanging groove 10 from the side surface 50a. Since the cushion member 50 has a smaller space between the main fibers 49 as compared with the mesh cushion member 3 of the first embodiment, the wire 5 is used to facilitate the insertion of the wire 51.
After heating 1, it was inserted into the cushion material 50. In this case, the heating temperature of the wire 51 was set to a temperature at which the main fiber 49 was softened, and a temperature at which the wire 51 did not adhere to the main fiber 49 (eg, about 150 ° C.). In addition, the wire 51 has a substantially straight shape without a convex portion for facilitating insertion into the cushion material 50.

As shown in FIG. 10, the insertion position of the first wire 51 was set to a depth of 10 mm from the bottom 10a of the suspension groove 10. The first wire 51 is 3 m in the suspension groove 10.
The opening 11 was previously formed so as to be exposed at a height of about m. In the same manner as in Example 1, the second
And the first wire 51 and the second wire were connected by hog ring inside the suspension groove 10.

When the cushion body of the third embodiment is recycled, the skin material is separated from the cushion material 50 by cutting the hog ring in the same manner as in the first embodiment, or the first material is removed in the same manner as in the second embodiment. The skin material is separated from the cushion material 50 by pulling out the wire 51 from the cushion material 50. By taking out the second wire from the hanging bag of the skin material, each wire could be separated from the cushion material in a short time.

[Comparative Example] Using a general prescription of a soft and highly elastic urethane foam, a hanging wire having a wire diameter of 1.8 mm was set at a predetermined position of an upper mold whose temperature was previously adjusted to 50 ° C. Mix the raw materials of urethane foam, 25
The mixture was adjusted to a temperature of 0 ° C., mixed, poured into a mold, foamed, and released after 10 minutes. Thereafter, bubbles were communicated by crushing to obtain a cushion body integrally formed with the hanging wire. The wire inserted in the hanging bag of the skin material and the hanging wire embedded in the cushion body were connected using a hog ring.

In order to recycle the cushion body of the comparative example, the skin material and the cushion body are separated by cutting the hog ring with a tool, and then the wire is extracted from the hanging bag. On the other hand, after cutting the cushion body with a knife along the hanging wire embedded in the cushion body, it is necessary to peel off the hanging wire from the cushion body while tearing the cushion body. In this case, it took about 8 minutes to separate the wires. This was practically difficult to recycle because urethane foam was firmly adhered to the suspended wire.

[0042]

According to the first aspect of the present invention, it is easy to recycle a cushion body having a hanging wire for fixing a skin material to a cushion material. According to the second aspect of the present invention, in addition to the effects of the first aspect, it is possible to provide a lightly recyclable cushion body having a three-dimensional random loop network structure having good air permeability, excellent sag resistance, and light weight. According to the invention described in claim 3,
In addition to the effects of the first aspect, it is possible to provide a lightweight cotton-like fiber structure that is easy to recycle and has good air permeability, excellent set resistance, and lightweight.

According to the fourth, fifth and sixth aspects of the present invention, since the hanging portions of the first and second wires can be seen in the hanging grooves, the first and second wires can be viewed by a connecting tool such as a hog ring. Can be easily performed. According to the invention described in claim 7, the handling of the wire is safe and easy by the loop provided at the end of the wire. According to the invention described in claim 8, the first wire can be pulled out from the cushion material without cutting the connecting tool such as the hog ring at the time of disassembly, and the disassembly work is further facilitated.

According to the ninth aspect of the present invention, it is possible to efficiently manufacture a lightweight cushion body having a three-dimensional random loop mesh structure, a skin material, and a suspension wire and having excellent breathability and cushioning properties. The manufacturing cost can be reduced, for example, the processing steps are short and the number of work steps is small. In addition, the cushion body manufactured by this manufacturing method can be easily dismantled during recycling.

[Brief description of the drawings]

FIG. 1 is a perspective view of a cushion body showing a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a part of the cushion body taken along line F2-F2 in FIG.

FIG. 3 is a perspective view of a mesh cushion material used for the cushion body shown in FIG. 1;

FIG. 4 is a plan view showing a suspension groove portion of the mesh cushion material shown in FIG. 3;

FIG. 5 is a cross-sectional view of the mesh cushion material taken along line F5-F5 in FIG.

FIG. 6 is an enlarged cross-sectional view showing a part of the mesh cushion material shown in FIG. 5;

FIG. 7 is a front view of a part of a skin material used for the cushion body shown in FIG. 1;

FIG. 8 is a front view partially showing a cross section of a wire and a hog ring used in a cushion body according to a second embodiment of the present invention.

FIG. 9 is a side view of an apparatus for manufacturing a mesh cushion material.

FIG. 10 is a sectional view of a fibrous cushion material according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cushion body 2 ... Continuous linear body 3 ... Reticulated cushion material 4 ... Skin material 4a ... Hanging part 10 ... Hanging groove 11 ... Opening 15 ... First wire 16 ... Convex part 17 ... Loop 23 ... Hanging Bag 25 ... second wire 26 ... window 27 ... hog ring (connecting tool) 50 ... fibrous cushion material 51 ... first wire

Claims (9)

[Claims] 1. A cushion material having a three-dimensional net-like structure or a cotton-like fiber structure composed of a plurality of linear bodies having mutually interlaced points bonded thereto and having a suspension groove formed on a surface side, and a suspension of the cushion material A plug-in first wire that is inserted from the side surface of the cushion material to a predetermined position along the insertion groove and is not bonded to the linear body, and covers the cushion material and corresponds to the suspension groove. A skin material provided with a second wire at a hanging portion; and a connector for connecting the first wire and the second wire to each other in a hanging groove of the cushion material. Cushion body to do. 2. The cushioning material according to claim 1, wherein a plurality of continuous linear bodies made of a thermoplastic resin and having a fineness of 300 to 100,000 deniers are each bent in a loop shape, and have an apparent density of 0 when fused to each other. 0.005 to 0.2 g / cm
Cushioning body according to claim 1, characterized in that the mesh cushion material having a ^third three-dimensional network structure. 3. The cushioning material according to claim 1, wherein said cushioning material is a fibrous cushioning material having a cotton-like fiber structure in which a plurality of entangled points of a thermoplastic resin are joined by a thermoplastic binder resin. The cushion body according to 1. 4. The cushion body according to claim 1, wherein an opening for exposing a part of said first wire is formed at a bottom of the suspension groove of said cushion material. 5. The cushion body according to claim 4, wherein a protrusion projecting from the opening into the hanging groove is formed at an intermediate portion in the longitudinal direction of the first wire. 6. A hanging bag for accommodating said second wire in said skin material, and said hanging bag is provided in said hanging bag.
5. The cushion body according to claim 4, wherein a window for exposing a part of said wire is formed. 7. The cushion body according to claim 1, wherein a loop is formed at an end of the first wire. 8. The connecting tool is a hog ring, and the inner diameter of the hog ring is sized so that a protrusion formed at a longitudinally intermediate portion of the first wire and the loop can pass through. The cushion body according to claim 7, wherein 9. A cushion having a three-dimensional net-like structure by discharging a softened thermoplastic resin from a plurality of nozzles, thereby winding a plurality of continuous linear bodies in a loop shape and fusing their contact portions with each other. A step of forming a material; a step of forming a suspension groove in the cushion material; a step of inserting a first wire into the cushion material from the side surface of the cushion material to a predetermined position along the suspension groove; Accommodating a second wire in a hanging bag provided in a material, and the first wire and the second wire in the hanging groove.
Connecting the wires to each other with a connecting tool.