Cushion member and manufacturing method thereof

Abstract

To provide a cushion member production method capable of easily producing a cushion member which hardly gets musty, which does not require a complicated unit, and can suppress occurrence of bed sore on a specific portion such as a bone protrusion portion.SOLUTION: There is provided a production method of a cushion member for producing a cushion member for supporting a user in a thickness direction using a substantially plate-shaped filament three-dimensional conjugate which is obtained by partial fusion of a plurality of filaments formed of a thermoplastic resin or a thermoplastic elastomer, the production method comprises: compression processing for pressing a top face of the filament three-dimensional conjugate by a compression member for plastic deformation, for providing a smooth recess on a position corresponding to one or a plurality of specific portions of the user; and heating processing for heating the filament three-dimensional conjugate for easily causing the plastic deformation.SELECTED DRAWING: Figure 3A

Description

[Technical field]

[0001] The present invention relates to a cushion member that can be used for mattresses, pillows, chairs, etc., and is advantageous in preventing bedsores, and a method for manufacturing the same. [Background technology]

[0002] Bed sores, commonly known as bed sores, develop when the capillaries in the skin are compressed by body weight for a long period of time, cutting off blood flow in the capillaries and preventing sufficient oxygen and nutrients from reaching the skin cells. Healthy people can turn over in their sleep, so even if the capillaries in the skin are temporarily compressed and blood flow is cut off, the pressure is relieved by turning over, so there is a low risk of developing bed sores.

[0003] However, if you are unable to turn over freely while sleeping due to weakened muscles, pressure on the skin continues for a long time, making you more susceptible to developing bedsores. Sitting in a chair for a long time also makes you more susceptible to developing bedsores.

[0004] Here, Fig. 19 shows a user lying on his back using a conventional, general cushion member for a mattress 101 and a pillow cushion member 102. Fig. 20 shows a user sitting on a chair using a conventional, general cushion member for a chair 103. Fig. 21 shows parts of the human body where bedsores are likely to develop.

[0005] When lying on one's back, pressure is generated locally on bony prominences (bony protuberances) such as the shoulder blades, sacrum, heels, or back of the head due to the rebound force from the cushioning material caused by the user's weight, making bedsores more likely to develop. Also, when sitting, bedsores are more likely to develop on bony prominences such as the tailbone.

[0006] As a method for preventing bedsores, for example, Patent Document 1 discloses a urethane mattress that acquires three-dimensional data of the human body and creates depressions that fit the shape of the body. Although this provides excellent body pressure dispersion, the urethane foam used as the material for the mattress has drawbacks such as low breathability, which makes it prone to becoming stuffy, and because it cannot be washed with water, it can easily become unsanitary.

[0007] Patent Document 2 discloses an air mattress made of multiple air cells with adjustable internal pressure. Although this provides excellent body pressure dispersion, it requires a complex device to control the pressure of each air cell, which increases costs, and therefore has not yet become widespread.

[0008] Meanwhile, Patent Documents 3 and 4 disclose mattresses using three-dimensional filament bonded bodies (three-dimensional mesh structures) that are well ventilated and have excellent body pressure dispersion and breathability. Mattresses using three-dimensional filament bonded bodies can easily adjust the resilience according to the body shape of each individual user, and have excellent breathability and body pressure dispersion, so they have the effect of reducing pressure (localized pressure) and stuffiness (humidity), which are major enemies of bedsores. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2017-074333 A [Patent Document 2] WO2011 / 096114 publication [Patent Document 3] JP 2010-154965 A [Patent Document 4] WO2017 / 122370 publication Summary of the Invention [Problem to be solved by the invention]

[0010] However, even if a cushion member using a filament three-dimensional bond with excellent body pressure dispersion is used, the cushion member has the characteristics of an elastic body in which the repulsive force increases according to the amount of sinking in. Therefore, there was a problem that the repulsive force of the mattress becomes high near bone protrusions (downward convex parts) where the amount of sinking is locally maximum, and blood flow in the capillaries in such areas is obstructed, making bedsores more likely to occur.

[0011] In view of the above problems, the present invention aims to provide a cushion member that is less likely to become stuffy, does not require complicated equipment, and can suppress the occurrence of bedsores in specific areas such as bony prominences, as well as a manufacturing method that can easily manufacture such a cushion member. [Means for solving the problem]

[0012] The manufacturing method of the present invention is a method for manufacturing a cushion member that supports a user in the thickness direction using a roughly plate-shaped three-dimensional filament bond in which multiple filaments made of thermoplastic resin or thermoplastic elastomer are partially fused together, and includes a pressure treatment in which the upper surface of the three-dimensional filament bond is pressed with a pressure member to cause plastic deformation and provide smooth depressions at positions corresponding to one or more specific parts of the user, and a heat treatment in which the three-dimensional filament bond is heated so that the plastic deformation is more likely to occur.

[0013] According to this manufacturing method, it is possible to easily manufacture a cushion member that is less likely to become stuffy, does not require complicated equipment, and can suppress the occurrence of bedsores in specific areas such as bone prominences. Note that the "smooth depression" in this application refers to a depression that has a surface formed into a substantially curved shape and is formed so that there are substantially no sharp edges such as steps.

[0014] More specifically, the manufacturing method may be such that the heat treatment is a process of heating the three-dimensional bound filaments to a predetermined temperature, the predetermined temperature being within a range from a temperature 30° C. lower than the melting point of the raw material to a temperature 5° C. lower than the melting point. More specifically, the manufacturing method may be such that the heat treatment is a process of bringing hot water at the predetermined temperature into contact with the three-dimensional bound filaments.

[0015] More specifically, the manufacturing method may be such that the heat treatment is a process of immersing a portion of the three-dimensionally bound filaments from the lower surface to a predetermined height in the hot water, the predetermined height being 20% ​​to 60% of the thickness of the three-dimensionally bound filaments.More specifically, the heat treatment is a process of applying hot air at the predetermined temperature to the three-dimensionally bound filaments.

[0016] More specifically, the heat treatment may be performed in parallel with the pressure treatment, and may be a process in which hot air is blown onto the upper surface of the three-dimensionally bound filaments while cold air is blown onto the lower surface of the three-dimensionally bound filaments. Note that the "cold air" in this application refers to air at least at a temperature lower than that of hot air, and is preferably air at room temperature (e.g., 25°C) or lower.

[0017] More specifically, the above-mentioned manufacturing method may include a condition adjustment process carried out after the heating process and the pressurizing process, the condition adjustment process being a process of applying cold air to an upper surface of the filament 3-dimensional combined body while applying hot air to a lower surface of the filament 3-dimensional combined body.

[0018] Furthermore, the cushion member of the present invention is a cushion member that supports a user in the thickness direction, and is composed of a roughly plate-shaped three-dimensional filament assembly in which a plurality of filaments made of thermoplastic resin or thermoplastic elastomer are partially fused together, and is configured such that smooth depressions are formed on the upper surface at positions corresponding to one or more specific parts of the user.

[0019] The cushion member according to the present invention may also be a cushion member having the above-mentioned cushion member and a cushion body arranged to cover the upper side of the cushion member, the cushion body being composed of a substantially plate-shaped three-dimensional filament bond formed by partially fusion of a plurality of filaments made of a thermoplastic resin or a thermoplastic elastomer. Effect of the Invention

[0020] The cushion member according to the present invention is less likely to become stuffy, does not require a complicated device, and can suppress the occurrence of bedsores in specific areas such as bone prominences. In addition, the cushion member according to the present invention can be easily manufactured. [Brief description of the drawings]

[0021] [Figure 1A] FIG. 1 is a plan view of a cushion member 1 according to the present embodiment. [Figure 1B] 2 is a cross-sectional view of the cushion member 1 as viewed from the right side. FIG. [Diagram 2] 4 is a flowchart of a method for manufacturing the cushion member according to the first embodiment. [Figure 3A] FIG. 4 is an explanatory view relating to a recess forming step in the first embodiment. [Figure 3B] FIG. 2 is a front view of a first pressure member 11a. [Figure 4] FIG. 2 is a configuration diagram of a vertical protrusion 15 which is a component part of the first pressure member 11a. [Diagram 5] FIG. 2 is a configuration diagram of a horizontal plate 16 which is one component of the first pressure member 11a. [Figure 6] FIG. 2 is a cross-sectional view of a cushion member 1W having a two-layer structure. [Figure 7A] FIG. 1 is a cross-sectional view of a cushion member 1X for a pillow according to the present embodiment. [Figure 7B] FIG. 2 is a plan view of the cushion member 1X. [Figure 8A] 1 is a cross-sectional view of a cushion member 1Y for a chair according to the present embodiment. [Figure 8B] FIG. 2 is a plan view of a cushion member 1Y. [Figure 9] 13 is an explanatory view relating to a recess forming step in the second embodiment. FIG. [Figure 10] 10A to 10C are explanatory diagrams relating to a change in density during the recess forming step. [Figure 11] 13 is an explanatory view relating to a recess forming step in the third embodiment. FIG. [Figure 12] 11 is an explanatory diagram regarding hot air supply in the recess forming step. FIG. [Figure 13] FIG. 11 is a front view of a first pressure member 11a according to a third embodiment. [Figure 14] 1 is a perspective view of the pressing member 11a as seen obliquely from above. [Figure 15] 1 is a perspective view of the pressing member 11a as seen obliquely from below. [Figure 16] 13 is an explanatory view relating to a recess forming step in the fourth embodiment. FIG. [Figure 17] 13 is a flowchart of a method for manufacturing a cushion member according to a fifth embodiment. [Figure 18A] FIG. 13 is an explanatory view relating to a pressure treatment according to a fifth embodiment. [Figure 18B] FIG. 13 is an explanatory diagram relating to a reversing process according to the fifth embodiment. [Figure 18C] FIG. 13 is an explanatory diagram relating to a state adjustment process according to the fifth embodiment. [Figure 18D] 11A and 11B are explanatory diagrams relating to the formation of a low-density region by the condition adjustment process. [Figure 19] FIG. 1 is an explanatory diagram showing a state in which a user is sleeping in a supine position. [Figure 20] FIG. 1 is an explanatory diagram showing a user sitting on a chair. [Figure 21] FIG. 1 is an explanatory diagram showing parts of the human body where bedsores are likely to occur. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Each embodiment of the present invention will be described below with reference to the drawings. In the following description, the up-down, left-right, and front-rear directions (directions perpendicular to each other) are as shown in the drawings. These directions are merely defined for the sake of convenience.

[0023] 1. First embodiment First, a first embodiment of the present invention will be described. Fig. 1A is a plan view (appearance view seen from above) of a cushion member 1 according to this embodiment. Fig. 1B is a cross-sectional view of the cushion member 1 seen from the right side (cross-sectional view taken along the plane indicated by the dashed line X in Fig. 1A).

[0024] The cushion member 1 can be used as bedding, and it is assumed that a user lies on the upper side of the cushion member 1 as shown by the dashed lines in Figures 1A and 1B. On the upper surface of the cushion member 1, there are formed smooth depressions, namely, scapular depressions 1a at two locations corresponding to the left and right scapular parts of the user, a sacral depression 1b at one location corresponding to the sacrum part of the user, and heel depressions 1c at two locations corresponding to the heels of both feet of the user.

[0025] 2 is a flowchart showing the manufacturing method (steps S1 to S3) of the cushion member 1. Below, an overview of these steps will be described.

[0026] Step S1 is a process (preparation process) for preparing a plate-like body 1p used to form the cushion member 1. The plate-like body 1p corresponds to the cushion member 1 before processing. The plate-like body 1p is a plate-like three-dimensional filament bonded body in which a plurality of filaments made of thermoplastic resin or thermoplastic elastomer are partially fused together.

[0027] As the plate-like body 1p, for example, a plate-like three-dimensional filament bond obtained by partially fusing a plurality of filaments made of polyethylene resin and having a diameter of 1 mm can be used. A specific example of the plate-like body 1p is a plate-like three-dimensional filament bond having a porosity of 95%, a length (front-rear dimension) of 2 m, a width (left-right dimension) of 0.6 m or 1 m, and a thickness (up-down dimension) of 5 cm. Note that the shape of the plate-like body 1p in this embodiment is rectangular when viewed from above and formed into a plate with a uniform thickness, but various approximately plate-like shapes can be adopted within the scope of the present invention.

[0028] The raw material of the plate-like body 1p (filament three-dimensional bonded body) is not particularly limited, but for example, polyethylene-based elastomer, polypropylene-based elastomer, polyester polyether-based elastomer, polystyrene-based elastomer, etc. can be used. As a method for producing the filament three-dimensional bonded body (three-dimensional network structure), various known methods can be applied, and for example, the methods disclosed in Patent Document 3 (JP Patent Publication 2010-154965 A) or Patent Document 4 (WO2017 / 122370 A) can be used.

[0029] By manufacturing the plate-like body 1p according to the method disclosed in these publications, a smooth, high-density surface layer is formed on the surface of the plate-like body 1p. However, the surface of the plate-like body 1p needs to be smooth enough that the protrusions caused by the filaments are not felt (the filaments do not irritate the body when they touch the body), and the surface layer does not necessarily need to be high-density.

[0030] Step S2 is a step (depression forming step) of forming the above-mentioned depressions 1a to 1c in the plate-like body 1p prepared in step S1. In the depression forming step, a heat treatment S2a and a pressure treatment S2b are performed. The heat treatment S2a in this embodiment is a process of adjusting the temperature of the plate-like body 1p by supplying hot water (heating means) adjusted to a predetermined temperature to the plate-like body 1p.

[0031] On the other hand, the pressurization process S2b is a process in which pressure is applied to predetermined positions on the upper surface of the plate-like body 1p using protruding pressurizing members while heating the plate-like body 1p with the above-mentioned hot water. The positions to be pressed are set to correspond to one or more specific parts of the user (bony protuberances where bedsores are likely to occur). In this embodiment, as an example, the positions are set to the positions of a total of five depressions (1a to 1c) shown in FIG. 1A.

[0032] By applying pressure to the plate-like body 1p with a pressure member while maintaining the plate-like body 1p at a predetermined temperature below the melting point of its raw material (thermoplastic resin or thermoplastic elastomer), the pressed portion of the plate-like body 1p undergoes plastic deformation to form a depression. As a method of applying pressure, for example, a method of applying pressure continuously for a predetermined time, or a method of applying pressure intermittently while measuring the depth of the depression formed by the plastic deformation may be adopted, but other methods may also be adopted.

[0033] Step S3 is a step (cooling step) of cooling the plate-like body 1p that was heated in the dent formation step (step S2). In this cooling step, the supply of hot water to the plate-like body 1p is stopped and the hot water is removed, and then air is blown toward the plate-like body 1p using an air blower (not shown) to cool the plate-like body 1p to a temperature (e.g., 25°C) at which plastic deformation does not occur. Through the above steps, a cushion member 1 is formed with smooth dents 1a-1c on the upper surface.

[0034] Fig. 3A shows the state of the depression forming process (step S2) for the plate-like body 1p accommodated in the water tank 10. Fig. 3A (as well as Figs. 6, 9, 10 to 12, 16, and 18A to 18D described below) is shown as a cross-sectional view from the same perspective as Fig. 1B. Fig. 3B is a front view of the first pressure member 11a (a configuration diagram from the right perspective).

[0035] 3A, the plate-like body 1p is pressurized by the pressurizing members 11a to 11c while being heated in the hot water HW stored in the water tank 10. Note that the water level of the hot water HW in this embodiment is set high enough so that the entire plate-like body 1p is immersed in the hot water HW, and the entire plate-like body 1p is heated.

[0036] Two first pressure members 11a are provided to correspond to the two scapular recesses 1a, one second pressure member 11b is provided to correspond to the sacral recess 1b, and two third pressure members 11c are provided to correspond to the two heel recesses 1c. By applying pressure using these pressure members 11a to 11c, the cushion member 1 having the recesses 1a to 1c described above can be formed. In addition, as in this embodiment, a method is adopted in which the plate-like body 1p is plastically deformed by applying pressure using a pressure member to form the recesses 1a to 1c, without using cutting or the like, so that it is easy to make these recesses smooth.

[0037] In this embodiment, the specific areas where bedsores are to be prevented are the scapula, sacrum, and heels, and smooth depressions are provided at positions corresponding to these areas to form the mattress cushion member 1. However, the cushion member according to the present invention is not limited to this example, and it is possible to designate only some of the scapula, sacrum, and heels as specific areas, or to add other areas as specific areas.

[0038] Next, the configuration of the first pressure member 11a will be described in more detail. The configurations of the second pressure member 11b and the third pressure member 11c are basically the same as that of the first pressure member 11a, so detailed description will be omitted here. Figure 4 is a configuration diagram of the vertical protrusion 15, which is a component of the first pressure member 11a, and Figure 5 is a configuration diagram of the horizontal plate 16, which is a component of the first pressure member 11a. In Figures 4 and 5, the upper side shows a configuration diagram from an upward perspective, and the lower side shows a configuration diagram from a side perspective.

[0039] The first pressure member 11a is composed of a vertical protrusion 15 and a horizontal plate 16. The vertical protrusion 15 is a metal member (e.g., a stainless steel member) having a hemispherical tip 15a and a cylindrical body 15b. The horizontal plate 16 is a square plate-shaped metal member (e.g., a stainless steel member) having a circular through hole 16a in the center. By inserting the vertical protrusion 15 into the through hole 16a and fixing it to the horizontal plate 16, it is possible to obtain the first pressure member 11a in which the hemispherical tip 15a protrudes a predetermined amount from the lower surface of the horizontal plate 16.

[0040] The means for fixing the vertical protrusion 15 to the horizontal plate 16 may be, for example, welding or adhesion with an adhesive. Alternatively, a screw-type fixing means (a means for fixing the vertical protrusion 15 as a male thread and the horizontal plate 16 as a female thread by screwing them together) may be used by providing a spiral groove in each of the cylindrical body 15b and the through hole 16a.

[0041] The amount of protrusion of the hemispherical tip 15a from the horizontal plate 16, and the size and curvature of the curved surface of the hemispherical tip 15a may be set according to the shape of the specific part of the user where bedsores are to be prevented (the bony protrusion where bedsores are to be prevented), and may be set differently for all or a part of the pressure members 11a to 11c. Additionally, the vertical protrusion 15 may be formed based on the shape of the user's bones, etc., so as to effectively prevent bedsores.

[0042] The first pressure member 11a has an upper portion of the vertical protrusion 15 connected to a drive device (not shown) and is moved vertically so as to appropriately pressurize the plate-like body 1p. When the horizontal plate 16 is moved until the lower surface of the horizontal plate 16 approaches or comes into contact with the upper surface of the plate-like body 1p, the plate-like body 1p is pressed by the amount of the hemispherical tip 15a protruding from the horizontal plate 16. In addition, the smoothly curved hemispherical tip 15a presses the plate-like body 1p, so that a smooth depression is easily formed.

[0043] The temperature of the hot water HW stored in the water tank 10 is adjusted to a predetermined temperature using, for example, a heating device, a circulation device, and a temperature sensor (not shown). If the temperature of the hot water HW is too low, plastic deformation is unlikely to occur and depressions are not properly formed, whereas if the temperature of the hot water HW is too high, unwanted plastic deformation is likely to occur in unpressurized areas.

[0044] Therefore, it is preferable that the temperature of the hot water HW is adjusted to a predetermined temperature within a range from a temperature 30°C lower than the melting point of the raw material (thermoplastic resin or thermoplastic elastomer) of the plate-like body 1p to a temperature 5°C lower than the melting point (hereinafter, for convenience, may be referred to as the "proper temperature range"). This makes it possible to heat the plate-like body 1p (filament three-dimensional bonded body) so as to approach the predetermined temperature within the proper temperature range.

[0045] The cushion member 1 manufactured by the above-mentioned manufacturing method is formed of a filament three-dimensional bond that can reduce pressure and stuffiness, and has smooth depressions 1a to 1c formed on the upper surface at positions corresponding to bone prominences such as the scapular region, sacrum region, and heel region. This makes it possible to locally reduce the repulsive force from the cushion member 1 that the user's bone prominences receive. Therefore, the cushion member 1 has a simple structure, but can suppress excessive pressure on the skin near the bone prominences and prevent bedsores. Since the depressions 1a to 1c are smooth, the skin near the bone prominences is prevented from hitting the angular parts in the depressions, and the user can obtain a smooth fit without feeling any unevenness. The cushion member 1 can be used as a mattress as it is, but it may also be used in a state where it is covered with a mattress cover or the like that is prepared separately.

[0046] The cushion member 1 can also be used in combination with another cushion body. Fig. 6 is a cross-sectional view of a two-layer cushion member 1W obtained by laminating a cushion body CS on the cushion member 1. The cushion body CS is a roughly plate-shaped three-dimensional filament bonded body in which a plurality of filaments made of thermoplastic resin or thermoplastic elastomer are partially fused. The cushion body CS may be the same as the plate-shaped body 1p, but made thinner.

[0047] As shown in FIG. 6, the cushion member 1W has a cushion body CS arranged so as to cover the upper surface of the cushion member 1 in which the depressions 1a to 1c are formed, and the user lies on the cushion body CS. This allows the cushion body CS to be interposed between the part of the user where bedsores are to be prevented (specific part) and each of the depressions 1a to 1c, making it possible to further increase the dispersibility of the pressure (pressure received from the cushion member 1W) that is locally maximized at the bone prominence of the specific part. The thickness of the cushion body CS may be appropriately adjusted according to the body type of the user. Furthermore, with the cushion member 1W, even if the difference between the shape of the specific part of the user and the shape of the depression is relatively large, the cushion body CS can be deformed to reduce the difference in pressure applied to the vicinity of the specific part of the user.

[0048] The above describes an example of a cushion member for a mattress according to this embodiment, but the cushion member and its manufacturing method are not limited to this and can be applied to cushion members and their manufacturing methods for various uses, such as cushion members for pillows and cushion members for chairs.

[0049] FIG. 7A is a cross-sectional view of a cushion member 1X for a pillow according to this embodiment (cross-sectional view when the cushion member 1X is cut along a plane that divides the cushion member 1X into two equal parts, left and right). FIG. 7B is a plan view of the cushion member 1X (outer view from above). A smooth occipital depression 1Xa is formed on the upper surface of the cushion member 1X at a position that contacts the occipital region of the user's head. This makes it possible to prevent bedsores at the bony prominences of the occipital region as much as possible. In this embodiment, the occipital region corresponds to the region (specific region) of the user where bedsores are to be prevented.

[0050] FIG. 8A is a cross-sectional view of a cushion member 1Y for a chair according to this embodiment (cross-sectional view when the cushion member 1Y is cut along a plane that divides the cushion member 1Y into two equal parts, left and right). FIG. 8B is a plan view of the cushion member 1Y (outer view from above). A smooth coccyx depression 1Ya is formed on the upper surface of the cushion member 1Y at a position that comes into contact with the tailbone of the user. This makes it possible to prevent bedsores at the bony prominence of the tailbone as much as possible. In this embodiment, the tailbone corresponds to the part (specific part) of the user where bedsores are to be prevented.

[0051] 2. Second embodiment Next, a second embodiment of the present invention will be described. The second embodiment is basically the same as the first embodiment, except that the water level of the hot water HW is lowered in the manufacturing method of the cushion member 1. In the following description, the emphasis is on the description of the points different from the first embodiment, and the description of the points common to the first embodiment may be omitted.

[0052] Fig. 9 shows the state of the recess forming step (step S2) in the manufacturing method of the cushion member according to the second embodiment. Fig. 10 shows the state of density change (plastic deformation) occurring in the plate-like body 1p near the first pressure member 11a in the recess forming step. The state near the other pressure members 11b and 11c is basically the same as that of the first pressure member 11a.

[0053] In this embodiment, as shown in Fig. 10, the water level of the hot water HW is set to about half the thickness of the plate-like body 1p, and only the lower half of the plate-like body 1p is directly heated. This allows the plastic deformation of the plate-like body 1p caused by the stress generated by the pressurization using the first pressurizing member 11a to occur preferentially in the lower half of the plate-like body 1p, forming a high-density region HD in the lower half of the plate-like body 1p, and preventing the density of the plate-like body 1p near the upper surface from increasing (i.e., becoming hard).

[0054] As a result, it is possible to prevent the repulsive force of the upper surface of the cushion member 1 that comes into contact with the part of the user where bedsores need to be prevented from becoming excessively high. In order to fully obtain such an effect, it is preferable to set the water level of the hot water HW to 20% to 60% of the thickness of the plate-like body 1p.

[0055] 3. Third embodiment Next, a third embodiment of the present invention will be described. The third embodiment is basically the same as the first embodiment, except for the form of the heating means and the pressure member for the plate-like body 1p and points related thereto. In the following description, the emphasis will be placed on the matters different from the first embodiment, and the description of the matters common to the first embodiment may be omitted.

[0056] Fig. 11 shows a state of the recess forming step (step S2) in the manufacturing method of the cushion member according to the third embodiment. Fig. 12 shows a state of hot air HA being supplied to the plate-like body 1p in the vicinity of the first pressure member 22a in the recess forming step according to this embodiment. Note that the state in the vicinity of the other pressure members 11b and 11c and the configurations of the other pressure members 11b and 11c are basically the same as in the case of the first pressure member 11a.

[0057] The manufacturing method of the cushion member according to the third embodiment is generally similar to that of the first embodiment in terms of the overall flow, but differs from that of the first embodiment in that hot air HA is used as a heating means (a means for performing a heat treatment) for the plate-like body 1p. In the recess forming step according to the third embodiment, the plate-like body 1p is placed on a ventilated support base 20, and then heated by hot air HA supplied from hot air supply members 21a to 21c arranged on the lower side of the ventilated support base 20. The ventilated support base 20 is provided with a large number of ventilation holes 20a (holes penetrating vertically) so that the hot air HA discharged from the hot air supply members 21a to 21c passes upward.

[0058] The first hot air supplying member 21a is disposed at a position facing the first pressure applying member 12a vertically (two positions corresponding to the left and right shoulder blades of the user), and heats the portion of the plate-like body 1p located almost directly above the first hot air supplying member 21a by supplying hot air HA upward. The second hot air supplying member 21b is disposed at a position facing the second pressure applying member 12b vertically (one position corresponding to the sacrum of the user), and heats the portion of the plate-like body 1p located almost directly above the second hot air supplying member 21b by supplying hot air HA upward. The third hot air supplying member 21c is disposed at a position facing the third pressure applying member 12c vertically (two positions corresponding to the heels of both feet of the user), and heats the portion of the plate-like body 1p located almost directly above the third hot air supplying member 21c by supplying hot air HA upward.

[0059] In the depression forming step, the upper surface of the plate-like body 1p is pressed by the pressure members 11a to 11c while the plate-like body 1p is heated by the hot air HA as described above. This causes the plate-like body 1p to plastically deform at that position, forming a depression. As described above, the heat treatment S2a in this embodiment is a process of adjusting the temperature of the plate-like body 1p by supplying the hot air HA to the plate-like body 1p. On the other hand, the pressure treatment S2b is a process of pressing a predetermined position on the upper surface of the plate-like body 1p using a protruding pressure member while heating the plate-like body 1p using the hot air HA. The heat treatment S2a may be performed not only in parallel with the pressure treatment S2b, but also before the pressure treatment S2b is started, so that the temperature of the plate-like body 1p can be adjusted in advance.

[0060] Fig. 13 is a front view of the first pressure member 11a according to this embodiment. Fig. 14 is a perspective view of the pressure member 11a from an obliquely upward perspective, and Fig. 15 is a perspective view of the pressure member 11a from an obliquely downward perspective. As shown in these figures, the first pressure member 11a is composed of a vertical protrusion 25 and a horizontal plate 26.

[0061] The vertical protrusion 25 is a metal member (e.g., a stainless steel member) having a hemispherical tip 25a and a cylindrical body 25b, and a plurality of ventilation holes 25h are formed in the hemispherical tip 25a. Each ventilation hole 25h communicates with an internal space 25c of the cylindrical body 25b, and the upper side of the internal space 25c is open. As a result, the hot air HA supplied from the hot air supply members 21a to 21c passes through the plate-like body 1p, and is then discharged above the cylindrical body 25b through each ventilation hole 25h and the internal space 25c.

[0062] The horizontal plate 26 is a square plate-shaped metal member (stainless steel) having a circular through hole 26a in the center, and by inserting the vertical protrusion 25 into the through hole 26a and fixing it to the horizontal plate 26, a first pressure applying member 11a can be obtained in which the hemispherical tip 25a protrudes a predetermined amount from the underside of the horizontal plate 26.

[0063] Examples of the means for fixing the vertical protrusion 25 to the horizontal plate 26 include welding and adhesion with an adhesive. Alternatively, a screw-type fixing means (means for fixing the vertical protrusion 25 as a male thread and the horizontal plate 26 as a female thread by screwing them together) by providing a spiral groove in each of the cylindrical body 25b and the through hole 26a may be used as the fixing means.

[0064] The amount of protrusion of the semispherical tip 25a from the horizontal plate 26, and the size and curvature of the curved surface of the semispherical tip 25a may be set according to the shape of the specific part of the user where bedsore is to be prevented (the bony protrusion where bedsore is to be prevented), and may be set differently for all or a part of the pressure members 11a to 11c. Furthermore, the vertical protrusion 25 may be formed so as to effectively prevent bedsores based on the shape of the user's bones, etc.

[0065] The temperature of the hot air HA is adjusted to a predetermined temperature using, for example, a heating device, a circulation device, and a temperature sensor (not shown). If the temperature of the hot air HA is too low, plastic deformation is difficult to occur and the depression is not properly formed. Conversely, if the temperature of the hot air HA is too high, deformation due to plastic deformation is likely to occur.

[0066] Therefore, it is preferable that the temperature of the hot air HA is adjusted to a predetermined temperature within a range (appropriate temperature range) from a temperature 30°C lower than the melting point of the raw material (thermoplastic resin or thermoplastic elastomer) of the plate-like body 1p to a temperature 5°C lower than the melting point. This makes it possible to heat the plate-like body 1p (filament three-dimensional bonded body) so as to approach the predetermined temperature within the appropriate temperature range.

[0067] In this embodiment, since hot water is not used as a heating means, after the recess forming step (step S2) is completed and the supply of hot air HA is stopped, it is possible to proceed to the cooling step (step S3) without removing the hot water. In the cooling step in this embodiment, cold air may be supplied from both or one of the pressurizing members 11a-11c and the hot air supply members 21a-21c toward the plate-like body 1p, and the plate-like body 1p may be cooled by the cold air. The cooling step cools the plate-like body 1p to a temperature (e.g., 25°C) at which plastic deformation does not occur, and the cushion member 1 can be obtained.

[0068] 4. Fourth embodiment Next, a fourth embodiment of the present invention will be described. The fourth embodiment is basically the same as the third embodiment, except that cold air is supplied from a pressure member to a plate-like body 1p. In the following description, the emphasis will be on the differences from the third embodiment, and the description of the commonalities with the third embodiment may be omitted.

[0069] 16 shows how hot air HA and cold air CA are supplied to plate-like body 1p near first pressure member 11a in the recess forming step (step S2) according to this embodiment. Note that the state near other pressure members 11b and 11c is basically the same as that of first pressure member 11a.

[0070] In this embodiment, as shown in Fig. 16, cold air CA is sent from the outside into the first pressurizing member 11a in parallel with the supply of hot air HA to the plate-like body 1p, and the cold air CA is discharged downward through each ventilation hole 25h. This makes it possible to heat the lower half of the plate-like body 1p intensively. That is, in the vicinity of the first pressurizing member 22a, the lower part of the plate-like body 1p is strongly influenced by the hot air HA supplied from the first hot air supplying member 21a and is heated moderately, while the upper part of the plate-like body 1p is not heated as much as the cold air CA is supplied from the first pressurizing member 22a.

[0071] This allows the plastic deformation of the plate-like body 1p caused by the stress generated by the pressure applied by the first pressure member 11a to occur preferentially in the lower half of the plate-like body 1p, forming a high-density region HD in the lower half of the plate-like body 1p, and preventing the density of the plate-like body 1p near the upper surface from increasing (i.e., becoming hard).As a result, it is possible to prevent the repulsive force of the upper surface of the cushion member 1 that comes into contact with the part of the user where bedsores need to be prevented from increasing excessively.

[0072] 5. Fifth embodiment Next, a fifth embodiment of the present invention will be described. The fifth embodiment is basically the same as the fourth embodiment except for the recess forming step. In the following description, the emphasis will be placed on the differences from the fourth embodiment, and the description of the commonalities with the fourth embodiment may be omitted.

[0073] 17 is a flowchart of a method for manufacturing a cushion member according to the fifth embodiment (steps S1 to S3). Step S1 is a step (preparation step) of preparing a plate-like body 1p used in forming the cushion member 1. This preparation step is similar to the preparation steps in the other embodiments, and therefore a detailed description thereof will be omitted here.

[0074] Step S2 is a step (depression forming step) of forming depressions 1a to 1c in the plate-like body 1p prepared in step S1. In the depression forming step (step S2) in this embodiment, a temperature adjustment process S2c, a pressure treatment S2d, an inversion process S2e, and a condition adjustment process S2f are performed.

[0075] The temperature adjustment process S2c is a process in which hot air HA is supplied from each of the hot air supplying members 21a-21c toward the plate-like body 1p at positions corresponding to each of the pressure applying members 11a-11c, and cold air CA is supplied from each of the pressure applying members 11a-11c toward the plate-like body 1p. By this temperature adjustment process, at the positions corresponding to each of the pressure applying members 11a-11c, the temperature of the lower portion of the plate-like body 1p is adjusted by the hot air HA, and the temperature of the upper portion of the plate-like body 1p is adjusted by the cold air CA.

[0076] As shown in Fig. 18A, the pressure treatment S2d is a process in which pressure is applied to predetermined positions on the upper surface of the plate-like body 1p using the pressure members 11a-11c while continuing to adjust the temperature of the plate-like body 1p using hot air HA and cold air CA. This pressure treatment process plastically deforms the plate-like body 1p to form a depression. Note that the pressure application positions and pressure application methods are similar to those in the pressure treatment S2b of the fourth embodiment, and therefore will not be described here. The process of applying (supplying) hot air HA to the plate-like body 1p in the temperature adjustment treatment S2c and pressure treatment S2d corresponds to the heating treatment according to the present invention.

[0077] The inversion process S2e is a process for inverting the plate-like body 1p upside down on the ventilated support stand 20. Fig. 18B shows the state in which the plate-like body 1p is inverted upside down on the ventilated support stand 20 by carrying out this inversion process.

[0078] In the condition adjustment process S2f, hot air HA supplied from the hot air supply members 21a-21c is applied to the area (upper surface of the plate 1p) where a depression has occurred due to plastic deformation in the upside-down plate 1p, and in parallel with this, cold air CA supplied from each of the pressure members 11a-11c is applied to the lower surface of the plate 1p. Fig. 18C shows how the condition adjustment process S2f is being performed. By performing the condition adjustment process S2f, only the vicinity of the depression is plastically deformed, and a low-density region LD (soft layer) can be formed as shown in Fig. 18D, making it possible to obtain a cushion member 1 with reduced repulsive force on the upper surface that comes into contact with a specific part of the user.

[0079] That is, immediately before the condition adjustment process S2f is performed, the vicinity of the depressions of the plate-like body 1p is likely to be relatively dense due to the pressure treatment S2d, and residual stress may be generated. Therefore, by performing the condition adjustment process S2f, it is possible to plastically deform the vicinity of the depressions on the upper surface of the plate-like body 1p to reduce the density and release the residual stress, while minimizing deformation of the lower surface side of the plate-like body 1p. In this way, the condition of the plate-like body 1p is adjusted, and a cushion member 1 with reduced repulsive force near the depressions on the upper surface can be obtained.

[0080] In this embodiment, the position on the plate-like body 1p where the hot air hits and the position where the cold air hits are reversed by performing the reversal process S2e to change the orientation of the plate-like body 1p. However, instead of doing so, when performing the condition adjustment process S2f, cold air may be supplied from the hot air supplying members 21a-21c and hot air may be supplied from each of the pressurizing members 11a-11c. In addition, the temperature of the above-mentioned hot air HA is preferably within a range from the melting point of the raw material of the plate-like body 1p to a temperature 20°C higher than the melting point, and hot air may be supplied intermittently to prevent heat from building up.

[0081] The process of step S3 is a process (cooling process) for cooling the plate-like body 1p that was heated in the recess forming process (step S2). This cooling process is similar to the cooling process of the fourth embodiment, and therefore a detailed description thereof will be omitted here.

[0082] 6.Other As described above, the manufacturing method of the cushion member in each embodiment includes a pressure treatment in which the upper surface of the plate-like body 1p (filament three-dimensional combined body) is pressed with a pressure member to cause plastic deformation and provide smooth depressions at positions corresponding to one or more specific parts of the user, and a heat treatment in which the plate-like body 1p is heated so as to make the plastic deformation more likely to occur.

[0083] This allows the surface of the plate-like body 1p to be plastically deformed by the pressure member while being heated, and makes it possible to form smooth depressions at positions corresponding to specific areas such as bone prominences without the need to use complex dies, etc. As a result, it is possible to easily manufacture a cushion member that is less likely to become stuffy and can reduce large localized pressure on bone prominences, etc.

[0084] The heat treatment is a process for heating the plate-like body 1p to a predetermined temperature, which is within a range from a temperature 30° C. lower than the melting point of the raw material of the plate-like body 1p to a temperature 5° C. lower than the melting point. This allows the temperature of the plate-like body 1p to be controlled to a temperature at which efficient plastic deformation can be achieved, and makes it possible to efficiently form smooth depressions.

[0085] In the first and second embodiments, the heat treatment is a process in which hot water HW at the predetermined temperature is brought into contact with the plate-like body 1p. This makes it possible to appropriately control the temperature of the plate-like body 1p while minimizing deformation. In particular, the heat treatment in the second embodiment is a process in which a portion of the plate-like body 1p from its lower surface to a predetermined height is immersed in hot water HW, and the predetermined height is set to 20% to 60% of the thickness of the plate-like body 1p.

[0086] As a result, plastic deformation of the plate-like body 1p caused by compression with the pressure member is less likely to occur near the top surface where the filaments do not come into contact with the hot water HW, and is more likely to occur near the bottom where the filaments come into contact with the hot water HW. This makes it possible to suppress an increase in the filament density on the top surface of the cushion member, and to prevent as much as possible the top surface of the cushion member that comes into contact with bone protrusions and the like from becoming hard (increasing the repulsive force).

[0087] On the other hand, in the third to fifth embodiments, the heat treatment is a treatment in which hot air HA at the predetermined temperature is applied to the plate-like body 1p. This allows the surface of the plate-like body 1p to be plastically deformed while being heated simply by using a hot air supplying device and a pressure member, so that it is possible to form smooth depressions without using large equipment such as a water tank.

[0088] In particular, the heating process of the fourth embodiment is a process performed in parallel with the pressurizing process, in which hot air HA is applied to the upper surface of the plate-like body 1p while cold air CA is applied to the lower surface of the plate-like body 1p. This makes it difficult for plastic deformation of the plate-like body 1p caused by compression with the pressurizing member to occur near the upper surface where the filaments are easily affected by the cold air CA, and makes it easier for it to occur near the bottom where the filaments are easily affected by the hot air HA. This makes it possible to suppress an increase in the filament density on the upper surface of the cushion member, and to prevent as much as possible the upper surface of the cushion member that comes into contact with bone protrusions and the like from becoming hard (increasing the repulsive force).

[0089] The manufacturing method of the cushion member in the fifth embodiment includes a condition adjustment process that is performed after the heating and pressurizing processes. This condition adjustment process is a process in which cold air is applied to the upper surface of the plate-like body 1p while hot air is applied to the lower surface of the plate-like body 1p. This adjusts the condition of the plate-like body 1p, and a cushion member with reduced repulsive force near the depression on the upper surface can be obtained.

[0090] Although the embodiment of the present invention has been described above, the configuration of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the invention. In other words, the above embodiment is an example in all respects and should be considered as not restrictive. The technical scope of the present invention is indicated by the claims, not the description of the above embodiment, and should be understood to include all modifications that fall within the meaning and scope of the claims. [Industrial Applicability]

[0091] The present invention can be used for a cushion member and a manufacturing method thereof. [Explanation of symbols]

[0092] 1, 1W, 1X, 1Y Cushioning material 1a Scapular depression 1b Sacral depression 1c Heel depression 1Xa Occipital depression 1Ya Coccygeal depression 1p Plate 10. Aquarium 11a First pressure member 11b Second pressure member 11c third pressure member 15 Vertical protrusion 15a Hemispherical tip 15b Cylindrical body 16 horizontal plate 16a Through hole 20 Ventilated support platform 20a Ventilation hole 21a First hot air supply member 21b Second hot air supply member 21c Third hot air supply member 25 Vertical protrusion 25a Hemispherical tip 25b Cylindrical body 25c interior space 25h ventilation hole 26 horizontal plate 26a Through hole

Claims

1. A method for manufacturing a cushion member that supports a user on an upper surface in a thickness direction by using a substantially plate-like three-dimensional filament assembly in which a plurality of filaments made of a thermoplastic resin or a thermoplastic elastomer are partially fused, the method comprising the steps of: a pressure treatment for pressing the upper surface of the filament three-dimensional assembly with a molding pressure member to plastically deform the upper surface, and providing smooth bone protrusion depressions corresponding to the shape of one or more bone protrusions of the user at positions corresponding to the bone protrusions; A manufacturing method characterized by including a heat treatment in which the lower surface side of the portion of the approximately plate-shaped filament three-dimensional bonded body where the bone protrusion depression is to be provided is heated to a higher temperature than the upper surface side so as to make the plastic deformation more likely to occur.

2. The manufacturing method according to claim 1, characterized in that after the heating treatment and the pressurizing treatment, a conditioning treatment is performed to reduce the density of the vicinity of the recess of the bone protrusion portion on the upper surface side of the approximately plate-shaped filament three-dimensional combination body.

3. The manufacturing method according to claim 2, characterized in that the conditioning treatment is a treatment in which only the vicinity of the bone protrusion depression on the upper surface side of the approximately plate-shaped filament three-dimensional combination body is heated to reduce the density of only that vicinity.

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