JPH0861412A - Fiber cushion body - Google Patents

Abstract

PURPOSE: To provide a cushion body hardly getting musty and capable of being cyclically, used while capable of decreasing the pain of the hip or the like in spite of many hours' sitting. CONSTITUTION: A fiber cushion body 1 comprises a three dimensional net structure 3 formed by bending plural continuous linear bodies 2 with 300 denier made of thermoplastic elastic resin in a loop, and fusing the contact parts between respective loops of the continuous linear bodies 2 to have apparent density of 0.005-0.20g/cm<3> , wherein a seat surface 4 for bearing load when the human body sits thereon is provided on the upper surface side, at least the continuous linear bodies 2 positioned just under the seat surface 4 are respectively disposed substantially horizontally along the seat surface 4, and the loops of those continuous linear bodies 2 are formed in such a manner as to rise in the vertical direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber cushion body suitable for furniture such as sofas and beds, including pads for seats for various vehicles.

[0002]

2. Description of the Related Art Conventionally, cushions used for furniture, beds, vehicle seats, etc. are made of integrally molded urethane foam, non-elastic crimped fibers such as polyester, or non-elastic crimps. Hard cotton and the like in which fibers are bonded with a binder are known. In particular, the foamed-crosslinked urethane has good durability as a cushioning body and good workability, and is therefore widely used in vehicle seats and the like.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
It has poor moisture permeability and water permeability, and because it has heat storage properties, there is the problem that the parts that come into contact with the human body easily get damp. Further, since urethane foam is not a thermoplastic resin, it is difficult to recycle it by remelting.

Further, the urethane foam has a skin layer a on its surface as shown in FIG. 5, so that the lower part of the buttocks of the seating surface sinks at the time of sitting, so that the skin layer a around the lower buttocks is formed.
Vertical stress and shearing stress are generated by being pulled obliquely. Therefore, the blood vessels in the buttocks in contact with the seating surface tend to be deformed and occluded, and blood flow may be obstructed, which may cause pain in the buttocks and fatigue if the user sits down for a long time.

On the other hand, a conventional cushion body made of synthetic fiber cotton in which thermoplastic polyester fibers are adhered by a binder is breathable, so that it does not easily get damp, but the crimp of the fibers does not have directionality over the entire cushion, and the seating Since the fibers are directly connected to each other in a lateral direction immediately below the surface, if the buttocks sink when seated, the lower part of the buttocks is pulled obliquely to the skin as in the case of urethane foam. Shear stresses tend to occur and impede blood flow. For this reason, the buttocks may become painful if the user sits down for a long time.

From a physiological point of view, it is known that the blood vessels of animals such as the human body are easily occluded by shear stress rather than vertical stress. Considering this, it is not a preferable phenomenon that the above-mentioned shear stress is generated on the seating surface of the cushion body, which is in contact with the human body. However, the conventional cushion body has not taken any measures against the occurrence of the shear stress on the seating surface.

Therefore, an object of the present invention is to provide a cushioning body which can reduce the pain of the buttocks and the like even when sitting for a long time, is less likely to get stuffy, is less tired, is recyclable and has excellent durability. It is in.

[0008]

The fiber type cushioning body of the present invention, which has been developed to achieve the above object, is formed by bending a plurality of continuous linear bodies of 300 denier or more mainly made of a thermoplastic elastic resin into a loop shape. A three-dimensional net-like structure formed by twisting and fusing the contact portions of the loops of these continuous linear bodies with each other to form an apparent density of 0.005 to 0.20 g / cm ³ ; The upper surface side has a seating surface that receives a load when a human body is seated, and at least the continuous linear bodies located immediately below the seating surface are arranged in a generally horizontal direction along the seating surface and It is characterized in that a loop of a continuous linear body immediately below the surface is formed to stand up and down.

As the thermoplastic elastic resin used for the network structure, for example, polyester elastomer, polyamide elastomer, polyurethane elastomer or the like can be applied. 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 nylon as a hard segment and polyethylene glycol or polypropylene glycol as a soft segment.

In the reticulated structure of the present invention, the thermoplastic elastic resin may be combined with a thermoplastic non-elastic resin. The thermoplastic non-elastic resin is, for example, polyester, polyamide, polyurethane or the like. The combination of these non-elastic resin and thermoplastic elastic resin is preferably a resin of the same series 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 elastomer and a polyurethane resin is recommended.

[0011]

The net-like structure used in the cushion body of the present invention is formed by winding a continuous linear body having a denier of 300 denier or more, which is mainly made of a thermoplastic elastic resin, to form a large number of amorphous loops, and each continuous linear shape. The body loops are brought into contact with each other in a molten state, and most of the contact portions are fused together to form a three-dimensional three-dimensional network structure.

Since the loop of the continuous linear body immediately below the seating surface stands upright in the vertical direction, only the portion to which a load is applied in response to the vertical pressure applied from above during seating is compressed downward, and the load is reduced. The compression ratio of the loop changes accordingly. Therefore, each loop can be flexed in the vertical direction as appropriate according to the uneven shape of the buttocks and the like, which is excellent in body shape compatibility.

This cushion body generates vertical stress in response to a seating load from above, but the generation of shear stress is extremely high compared to conventional urethane foam having a skin layer and cushion bodies made of hard cotton of various fibers. It is slight, and obstruction of blood flow due to shear stress in the skin around the lower buttocks is avoided. For this reason, it is possible to reduce the pain of the buttocks and the like even when sitting for a long time, and combined with good ventilation, it is less likely to get tired. The cushion body absorbs the stress while deforming the three-dimensional network structure even if it is subjected to a large deformation with a large stress during use, and when the stress is released, the three-dimensional network structure regains its original shape due to the rubber elasticity of the thermoplastic elastic resin. Can be restored to.

If the fineness of the continuous linear body of the cushion body is less than 300 denier, the strength is lowered and the repulsion force is lowered, which is not preferable. The fineness of the continuous linear body is preferably 300 denier or more, preferably 400 denier or more, and 10,000 or more, which can obtain a preferable repulsive force as a cushion body.
It is 0 denier or less. If the fineness exceeds 100,000 denier, the number of continuous linear members per unit volume of the cushion body will be small and the compression characteristics will be poor, such being undesirable. The fineness of the continuous linear body is more preferably 500 to
It is 50,000 denier.

The net-like structure of the present invention is unsuitable as a cushion body when the apparent density is less than 0.005 g / cm ³ , because the repulsive force is lost. Also 0.20 g / c
When it exceeds m ³ , the elasticity becomes too strong and the sitting comfort becomes poor, so it is also unsuitable as a cushion body.
For these reasons, the preferred apparent density of the reticulated structure, 0.005 g / cm ³ or more and 0.20 g / cm ³ or less, more preferably, 0.01 g / cm ³ or more,
It is 0.05 g / cm ³ or less. When this net-like structure is used for a cushion body such as a seat, the apparent density at the time of compression is 100 g / in order to obtain a comfortable sitting comfort while maintaining bulk retention, elasticity and breathability when sitting. preferably it has a bulkiness of 0.03g / cm ³ ~0.20g / cm ³ under a load of cm ^2, 0.05g / cm ³ ~
Those having a bulkiness of 0.20 g / cm ³ are particularly preferable.

[0016]

EXAMPLE As shown schematically in FIG. 1, the cushion body 1 of this example is composed mainly of a thermoplastic elastic resin.
It comprises a three-dimensional net-like structure 3 in which a plurality of continuous linear bodies 2 having a denier of 00 or more are meandered in a loop shape and the respective contact portions of the loops of these continuous linear bodies 2 are fused. The apparent density of the network structure 3 is set in the range of 0.005 to 0.20 g / cm ³ for the reason described above. The upper surface side of the cushion body 1 is a seating surface 4 that receives a load when a human body is seated. The outside of the seating surface 4 is covered with a breathable cover material (not shown).

In this cushion body 1, at least the continuous linear bodies 2 located immediately below the seating surface 4 are arranged in a generally horizontal direction along the seating surface 4, and the continuous linear body 2 immediately below the seating surface 4 is arranged. The direction of the loop is so that it stands up and down. In addition, all continuous linear bodies 2
May be arranged in a generally horizontal direction along the seating surface 4, and the loop of the continuous linear body 2 other than immediately below the seating surface 4 may be erected vertically.

The mesh structure 3 is manufactured by the mesh manufacturing apparatus 10 conceptually shown in FIG. An example of the reticulated body manufacturing apparatus 10 includes an extruder 15 and a nozzle unit 16. The extruder 15 heats the thermoplastic elastic resin raw material charged from the material supply port 20 to a temperature 10 ° C. to 80 ° C. higher than its melting point (for example, 40 ° C. higher temperature) and extrudes it toward the nozzle portion 16. Is. The thermoplastic elastic resin heated to the above temperature is discharged downward from the orifice of the nozzle portion 16 so as to continuously fall linearly and without interruption. In addition, the melting temperature of the thermoplastic elastic resin at the time of discharging is 30 ° C. to 50 ° C. from the melting point of the resin.
A high temperature is preferable because loops can be easily formed and the contact portions of the loops can be easily fused to each other.

The nozzle portion 16 has a nozzle effective surface 25 of, for example, a width of 60 cm and a length of 5 cm when viewed from the lower surface side.
On the nozzle effective surface 25, a large number of orifices having a hole diameter of 0.5 mm are provided with a hole pitch of 5 mm. The thermoplastic elastic resin is discharged from the orifice so that the discharge amount per orifice single hole is 0.5 g to 1.5 g / min. Below the nozzle portion 16, at a distance of about 50 cm from the nozzle effective surface 25, a cooling medium 3 such as water is provided.
0 is allocated. The cooling medium 30 is heated to around 70 ° C.

A conveyor 40 is provided below the nozzle portion 16. The conveyor 40 is, for example, a pair of stainless steel endless nets 41 and 42 having a width of 70 cm arranged in parallel with each other with an interval of 10 cm therebetween, and a part of the endless nets 41 and 42 is a cooling medium. It is exposed above 30. The endless nets 41 and 42 are continuously driven in an endless direction in the direction of the arrow in the figure by the rotating bodies 45 and 46.

The molten thermoplastic elastic resin is discharged from the orifice of the nozzle portion 16, and the endless net 4
Let it fall naturally between 1, 42. The molten thermoplastic elastic resin falls between the endless nets 41, 42, and the continuous linear bodies 2 are formed in the number corresponding to the number of orifices of the nozzle portion 16, while the endless nets 41, 4 are formed.
It's meandering between the two and stopping,
A random loop occurs. Therefore, these continuous linear bodies 2 each form a loop in a direction intersecting the A direction (for example, an arrow B direction) while continuously winding in the direction of the arrow A in FIG.

In this case, the hole interval pitch of each orifice of the nozzle portion 16 is set to a size such that the loops can contact each other, so that the loops are brought into contact with each other between the endless nets 41 and 42, and the contact portions of the loops are melted. The three-dimensional net-like structure 3 is obtained by attaching the three-dimensional net-like structure 3.

The net-like structure 3 in which the loops are fused is drawn into the cooling medium 30 at a speed of about 1 m / min while both side surfaces are restrained by the endless nets 41 and 42, and solidifies in the cooling medium 30. The fused portion of each loop is fixed. In addition, the temperature of the cooling medium 30 is set to the mesh structure 3
By keeping the annealing temperature (pseudo-crystallization promoting temperature) of (3), the pseudo-crystallization treatment of the network structure 3 can proceed at the same time.

The net-like structure 3 obtained through the above series of steps is subjected to pseudo-crystallization treatment at a temperature lower than the melting point of the thermoplastic elastic resin by 10 ° C. or more, if necessary, and then cut into a predetermined size. By doing so, a flat three-dimensional net-like structure 3 as shown in FIG. 1 was obtained. This reticulated structure 3 is
A number of continuous linear bodies 2 corresponding to the number of orifices of the nozzle portion 16 are continuous in the direction of arrow A (generally horizontal direction) while drawing a loop. The arrow B in the figure indicates the thickness direction of the network structure 3.

The reticulated structure 3 is molded into a predetermined three-dimensional shape by the cushion molding device 50 shown in FIG. The molding apparatus 50 includes a molding die 51 and a heater 5.
2 and a blower 53. The molding die 51 is
For example, it is a so-called simple aluminum mold made of an aluminum alloy or the like, and a large number of vent holes 60 and 61 are formed in the lower mold 55 and the upper mold 56 respectively like punching metal. The vent holes 60 and 61 have a hole diameter of 2 to 3 mm and a hole pitch of 10 to 20 mm. The hot air of 130 ° C. to 160 ° C. generated by the heater 52 and the blower 53 can be blown into the mold 51 through the ventilation holes 60 and 61.

The mesh structure 3 is housed in the mold 51, and the lower mold 55 and the upper mold 56 are closed to form the mesh structure 3.
To some extent in the thickness direction (plane direction). The thickness direction mentioned here is a direction (arrow B direction) orthogonal to the direction (arrow A direction in FIG. 1) in which the continuous linear bodies 2 of the network structure 3 are continuous.

The hot air is introduced into the mold 51 through the ventilation holes 60 and 61, and the hot air is blown to the mesh structure 3 to heat the thermoplastic elastic resin to the heat deformation temperature of the thermoplastic elastic resin. The body 3 is compressed. After a lapse of a predetermined time, the mold 51 was cooled and released from the mold to obtain a desired three-dimensional cushion body 1.

When the cushion body 1 is used for a seat such as a vehicle, a bed, a sofa, etc., the continuous linear bodies 2 are arranged substantially horizontally so that the direction A in which the continuous linear bodies 2 are continuous is along the seating surface 4. As a result, the loop of the continuous linear body 2 is erected vertically.

Since the cushion body 1 uses the net-like structure 3 having the erected loops as described above, as shown in FIG. 4, only a portion to which a vertical load is mainly applied when seated is compressed downward to reduce the load. The compression ratio of the loop changes accordingly. For this reason, it has excellent conformability to the body shape against the vertical pressure when seated. In this case, on the seating surface where the buttocks are in contact, vertical stress is generated by bending each loop in the vertical direction according to the uneven shape of the buttocks,
Normal stress is not enough to impede blood flow.

The occurrence of shear stress on the seating surface of the cushion body 1 is extremely small as compared with the conventional urethane foam having a skin layer (FIG. 5), and the blood vessel is affected by the shear stress acting on the skin. Occlusion is avoided. For this reason, it is possible to reduce the pain of the buttocks and the like even when sitting for a long time, and, together with the extremely good air permeability of the net-like structure 3, it is possible to prevent fatigue.

In the cushion body evaluation test, the cushion body 1 of this example had a temperature under the buttocks of 29 ° C. and a humidity of 30% after 30 minutes from sitting, whereas the conventional urethane foam was used. The cushion body had a temperature under the buttocks of 35 ° C. and a humidity of 72% after 30 minutes from sitting. Further, the temperature under the buttocks of the conventional cushion body made of hard cotton in which synthetic fibers are bound by a binder was 34 ° C. and the humidity was 43%.

[0032]

EFFECTS OF THE INVENTION According to the present invention, the body conformability to the vertical pressure applied from above at the time of sitting is excellent, and the occurrence of shear stress, which is a factor that obstructs blood flow in the buttocks etc. on the sitting surface, is reduced. Therefore, it is possible to reduce the pain of the buttocks and the like even if the user sits for a long time, and the ventilation is sufficient to prevent stuffiness.
Further, the net-like structure of the cushion body of the present invention is resistant to fatigue even under a large seating load and has high durability. Since it is mainly composed of a single thermoplastic resin that does not use a binder, it can be easily recycled and used.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing a net structure of a cushion body showing an embodiment of the present invention.

FIG. 2 is a schematic side view of an apparatus for manufacturing a reticulated structure.

FIG. 3 is a schematic cross-sectional view of a cushion body molding device.

FIG. 4 is a cross-sectional view showing a state where the cushion body shown in FIG. 1 is seated.

FIG. 5 is a cross-sectional view showing a state where a conventional cushion body is seated.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cushion body 2 ... Continuous linear body 3 ... Net structure 4 ... Seating surface 10 ... Net manufacturing device 50 ... Cushion forming device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location B29L 31:00 (72) Inventor Hideo Isoda 1-2-1 Katata, Otsu, Shiga Prefecture Toyobo Co., Ltd. Company Research Institute

Claims (1)

[Claims] 1. A 300 mainly composed of a thermoplastic elastic resin.
An apparent density of 0.005 to 0.20 g is obtained by bending a plurality of continuous linear bodies of denier or more into a loop shape and fusing the contact portions of the loops of these continuous linear bodies to each other.
/ Cm ³ formed of a three-dimensional net-like structure, having a seating surface on the upper surface side for receiving a load when a human body is seated, and the continuous linear shape positioned at least immediately below the seating surface. A fiber cushion body characterized in that a body is arranged in a generally horizontal direction along a seating surface and a loop of a continuous linear body immediately below the seating surface is formed to stand up and down.