Seat cushion with edge portion for use in a seat of a saddle-ride type vehicle, and manufacturing method thereof

Abstract

To provide a seat cushion for a saddle riding type vehicle and having an edge, the seat cushion that can easily be fastened to the skin and a support base, and is improved in drainage property.SOLUTION: A seat cushion has a 3-dimensional fiber structure where a core-sheath type fusible fiber and a frame fiber are heat-sealed and formed at an intersecting spot of the fibers. The fusible fiber sheath is formed of thermoplastic elastomer. This is eccentrically located at the fusion point between the fibers, and thereby a swelling portion is formed for each fusion point. The core of the frame fiber and the fusible fiber is formed of non-elastomer resin. The frame fiber is a bulky fiber subjected to crimped processing. The fineness of the frame fiber and the fusible fiber is in a range of 1-200 dtex. The seat cushion has a layered structure configured that multiple layers having the 3-dimensional fiber structure are heat-sealed to each other, respectively. The distribution of density and rigidity is provided due to the layered structure every region of the seat cushion.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a seat cushion for use in a seat of a saddle-ride type vehicle such as a motorcycle or a personal watercraft (PWC), and a manufacturing method thereof, and more particularly to a seat cushion having an edge portion along at least a part of the periphery of the seat cushion. The edge portion here is a portion forming the periphery, and is typically a portion having a smaller thickness than other regions on the inside, such as the vicinity of a narrowly defined seat portion that supports the weight of a rider vertically downward, or a portion having a thickness that tapers toward the periphery. [Background technology]

[0002] Soft urethane resin foams are generally used in various seat cushions. With urethane resin foams, it is relatively easy to realize physical properties that meet a variety of requirements by optimizing the selection of the resin raw materials, such as polyether or polyester, polyol such as polycarbonate, and polyisocyanate, and the setting of foam molding conditions.

[0003] On the other hand, some cushioning materials are made of thermoplastic resins such as polyester and have a three-dimensional mesh structure, and in recent years, their development for train seats and bedding (mattresses) has been progressing. Such three-dimensional cushioning materials made of polyester and the like have high breathability and are easy to recycle. Known examples of such cushioning materials include Teijin Frontier Co., Ltd.'s high-performance polyester cushioning material "Elk" (registered trademark) and Toyobo Co., Ltd.'s "Breath Air" (registered trademark). Toyobo Co., Ltd.'s "Breath Air" (registered trademark) has an appearance similar to a thin and bulky instant ramen, and is also used for motorcycle (motorcycle) seats (Non-Patent Document 2).

[0004] In contrast, Teijin Frontier Co., Ltd.'s high-performance polyester cushioning material "ELK" (registered trademark) has a three-dimensional structure in the form of a type of thermally bonded nonwoven fabric, and is capable of achieving an appearance, elasticity, and durability similar to that of soft urethane resin foam (Non-Patent Document 1). For this reason, it is also used in bra cups, baby stroller cushions, bedding cushions, furniture cushions, etc. High-performance polyester cushioning material "ELK" (registered trademark) uses bulky fibers that have been subjected to a crimping process, and a unique three-dimensional structure in which fusible resin is unevenly distributed and reinforced at the points where the fibers are entangled and fused to each other allows it to achieve excellent cushioning and durability.

[0005] In addition, the highly functional polyester cushioning material "ELK" (registered trademark) has been folded in an accordion shape to form a vertically oriented vertical nonwoven fabric (Non-Patent Document 3). Attempts have also been made to obtain a seat cushion structure for automobile seats by stacking sheet-like elastic bodies as such vertical nonwoven fabrics and fusing them by heating and pressurizing them in a mold (Patent Documents 1-2). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent 5308152 (International Publication WO2007 / 114229) [Patent Document 2] JP 8-318066 [Non-patent literature]

[0007] [Non-Patent Document 1] Makoto Yoshida, "Development of 3D Elastic Fiber Structure 'ELK'" SEN'IGAKKAISHI (Textiles and Industry) Vol. 52, No. 12 (1996) [Non-Patent Document 2] "What is BreathAir (registered trademark)?" (Toyobo Co., Ltd. website) https: / / www.toyobo.co.jp / seihin / breathair / what_breathair.htm [Non-Patent Document 3] elk (registered trademark) website "Combination Proposals" (Teijin Frontier Co., Ltd.) https: / / www.elk-fiber.net / combination DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0008] In the case of scooter-type motorcycles (such as Yamaha Motor Co., Ltd.'s "VINO" (registered trademark)) which can be said to be for short-distance city riding, the seat cushion often has a peripheral portion that forms a vertical wall or a bulging surface and does not have an edge portion. On the other hand, in the case of motorcycles capable of touring or off-road driving, the seat cushion often has an edge portion. Seat cushions for personal watercraft (jet skis) also often have an edge portion.

[0009] Seat cushions are usually covered with a skin, which is fixed to the body of the saddle-ride type vehicle or to the lid (support) of an engine room or storage room with a string or the like. In this case, if the seat cushion has edges, the edges may be pushed by the skin and pulled into the inside of the seat cushion. Therefore, it is necessary to place a frame material along the periphery of the seat cushion or devise a method of fixing.

[0010] It is also preferable that the seat cushion has a relatively good drainage property. For example, when the seat cushion is continuously exposed to heavy rain or splashes, water may enter through the seams of the cover or through the holes for the strings or threads used to secure the cover, causing the seat cushion to absorb a large amount of water. In such a case, poor drainage may make the seat cushion difficult to handle due to increased weight, etc. In particular, when the support part to which the seat cushion is attached forms a lid for an engine room or a storage room, it may be difficult to open such a lid.

[0011] On the other hand, if an attempt is made to obtain a molded article having edges by fusing sheet-like elastic bodies such as "ELK" (registered trademark) together to produce an elastic molded article as described above, it is expected that considerable ingenuity will be required in the manufacturing process, and no advantage has been found for using such a shape in applications. Therefore, since the development of cushioning materials with a three-dimensional net-like structure made of thermoplastic fibers, including "ELK" (registered trademark), no molded articles having such edges have been reported at all. The present invention was made possible only after numerous ingenuity in the process, and was made based on the discovery of new applications and the problems associated with them. [Means for solving the problem]

[0012] According to a preferred embodiment of the present invention, there is provided a seat cushion for a saddle-type vehicle, which has an edge portion and has a three-dimensional fiber structure formed by heat-fusing a core-sheath type fusible fiber and a skeletal fiber at the intersections of the fibers, the sheath of the fusible fiber is formed from a polyester / polyether elastomer or other thermoplastic elastomer, and this thermoplastic elastomer is unevenly distributed at the fusion points of the fibers to form bulging portions at each of the fusion points, the skeletal fiber and the core of the fusible fiber are formed from a non-elastomer resin, the skeletal fiber is a bulky fiber that has been subjected to a crimping treatment, and the fineness of the skeletal fiber and the fusible fiber is within the range of 1 to 200 dtex, the seat cushion has a layered structure in which a plurality of layers, each having the three-dimensional fiber structure, are fused to each other, the seat cushion has a density distribution due to the layered structure in each region of the seat cushion, and has a rigidity distribution that depends on this density distribution.

[0013] According to a preferred embodiment, at least one of the layers of the laminated structure extends to a peripheral edge of the seat cushion, and the layers of the laminated structure include a plurality of layers having longitudinal fibers oriented in a thickness direction. According to a preferred embodiment, the edge portion is a portion that is provided along at least a part of the peripheral edge of the seat cushion and has a smaller thickness than other areas, or a portion whose thickness tapers toward the peripheral edge.

[0014] According to a preferred embodiment, the seat cushion has at least two areas, apart from the edge area, which have a density and stiffness higher than the other areas, and which have different density levels. According to a preferred embodiment, the edge area has a density of 40 kg / m 3 Larger than 45 kg / m 3 or more than 50kg / m 3 The seat cushion has a shape-retaining frame for retaining the shape of the seat cushion. In a preferred embodiment, the seat cushion has a density of 40 kg / m3 or less except for the edge portion. 3 Smaller than 20-35 kg / m 3is within the range.

[0015] A method for manufacturing a seat cushion for a saddle-ride type vehicle according to a preferred embodiment of the present invention includes: preparing skeletal fibers as bulky fibers by subjecting fibers made of a non-elastomer resin to crimping processing; and preparing sheath-core fusible fibers by covering a core made of a non-elastomer resin with a sheath made of a polyester / polyether elastomer or other thermoplastic elastomer, wherein the fineness of the skeletal fibers and the fusible fibers is within a range of 1 to 200 dtex; and by mixing the sheath-core fusible fibers and the skeletal fibers in a state of short fibers and heating them, a sheet-like elastic body having a three-dimensional fiber structure in which the fibers are heat-fused at their intersections is formed; at this time, the thermoplastic elastomer forming the sheath of the fusible fibers is unevenly distributed at the fusion points between the fibers, thereby forming bulges at each of the fusion points, and at this time, the fibers are oriented in the thickness direction. To obtain a vertically oriented sheet elastic body, the sheet elastic body before being vertically oriented is folded in an accordion-like manner and then fused to each other. A plurality of sheet elastic bodies thus obtained are then stacked and placed in a mold under pressure and heat to heat-fuse the sheet elastic bodies to each other and form a seat cushion along the inner surface of the mold. At this time, the plurality of sheet elastic bodies include a plurality of vertically oriented ones, and a density distribution is formed depending on the degree of compression in the mold in each part of the seat cushion, as well as the density, thickness and number of layers of the sheet elastic bodies, and a rigidity distribution dependent thereon is also formed, with the edge portions having higher density and rigidity than other regions, and at least two regions other than the edge portions having different density levels. Effect of the Invention

[0016] According to the embodiment of the present invention, the peripheral edge portion can be easily made to have a rigid structure without using a separate frame material, and the structure or procedure for attaching the seat cushion to a saddle-type vehicle can be simplified. In addition, according to the embodiment of the present invention, since the seat cushion has a special fine net-like three-dimensional structure, it is possible to realize the same cushioning properties as a urethane resin foam, particularly the body pressure dispersion properties, and also to realize good water drainage properties. [Brief description of the drawings]

[0017] [Figure 1A] This is a photograph showing an example of a seat cushion (for two people) for a personal watercraft (PWC) with the cover attached. [Figure 1B] 1B is a photograph showing another example of a seat cushion (for three people) for a personal watercraft (PWC) with the cover attached, similar to FIG. 1A. [Figure 1C] FIG. 2 is an external perspective view showing an example of a motorcycle seat cushion with a cover attached, similar to FIGS. 1A to 1B. [Figure 2A] 13 is a photograph showing an upper mold for forming the underside of a seat cushion. [Figure 2B] 13 is a photograph showing a lower mold for forming the upper surface side of a seat cushion. [Diagram 3] 1 is a schematic plan view for explaining a plurality of regions having different densities and stiffnesses in a seat cushion, in which the seat cushion is shown in a state where it is pressed out flat; [Figure 4A] This is a photograph of a cut surface showing how the sheet-shaped elastic body of "ELK" (registered trademark) is laminated and fused. The photograph was cut along the front-rear and vertical directions of the seat cushion, and in particular shows the pilot's seat part (the part that supports the pilot from below) and the raised part (elliptical part) behind it. [Figure 4B] FIG. 4B is a schematic diagram corresponding to FIG. 4A, showing an example of a form in which sheet-shaped elastic bodies of "ELK" (registered trademark) are arranged and overlapped in a mold to form a pilot seat and a portion behind it. [Figure 4C] FIG. 2 is a schematic cross-sectional view of a laminate showing an example of a form in which sheet-shaped elastic bodies of "ELK" (registered trademark) are arranged and overlapped in a mold to form left and right edge portions. [Figure 4D] FIG. 13 is a schematic cross-sectional view showing another example of a form in which sheet-shaped elastic bodies of "ELK" (registered trademark) are arranged and overlapped in a mold to form left and right edge portions. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The seat cushion according to a preferred embodiment is an integrally formed porous elastic body obtained by laminating and fusing sheet-like elastic bodies of "ELK" (registered trademark) in a mold, as will be described in detail later. The seat cushion has an edge portion to which a separate frame material is not attached. In other words, when the seat cushion is molded, a separate frame material is embedded, or the seat cushion is attached to a support portion of a saddle-type vehicle without attaching a separate frame material during or after molding. This attachment can be performed by covering the seat cushion with a skin and fastening it with a string or the like.

[0019] In order to omit a separate frame material, the edge portion is formed rigidly when the seat cushion is molded in a mold. Specifically, the density of the edge portion can be increased by measures such as increasing the degree of compression or increasing the number of laminated sheets compared to other portions. In general, when the density of the sheet-like elastic body of "ELK" (registered trademark) is increased during molding in a mold, the rigidity increases in a manner almost proportional to the density. The rigidity of the elastic molded body obtained by fusing the sheet-like elastic body of "ELK" (registered trademark) in a mold can be evaluated by measuring the hardness at a constant compression of 40% or at a constant compression of 25% according to a method conforming to JIS K6400-2:2012 "Soft foamed material-Physical properties-Part 2: Method for determining hardness and compressive stress-strain characteristics". In other words, it is considered that the shape retention that replaces the frame material can be evaluated by the hardness at such a constant compression.

[0020] As the "ELK" (registered trademark) sheet-like elastic body (hereinafter simply referred to as "sheet-like elastic body") used to manufacture the seat cushion, it is preferable to mainly use the above-mentioned vertical type nonwoven fabric. In one preferred embodiment, the "ELK" (registered trademark) sheet before being folded in an accordion shape, that is, the sheet-like elastic body that does not have a vertical orientation (orientation in the sheet thickness direction), is not particularly oriented, or the fibers are oriented in a direction horizontal to the sheet, can be partially used. In particular, it can be locally arranged in the vicinity of the location that supports the weight of the pilot from vertically below (hereinafter referred to as the pilot's seat). In addition, in a preferred embodiment, each sheet-like elastic body has a substantially uniform thickness and density for ease of manufacture.

[0021] 1A to 1C show examples of seat cushions with a skin. The skin is typically synthetic leather, and is, for example, a nylon or polyester fabric (usually a sheet-like knitted or woven fabric) coated with a resin layer such as polyurethane. FIGS. 1A to 1B show seat cushions used in personal watercraft (PWC) for two and three people, respectively, and FIG. 1C shows seat cushions used in large motorcycles. The edge parts, which are peripheral parts with a small thickness, are formed at least in the front parts of the left and right edges, and are particularly formed in the edges on the left and right sides that face upward toward the front. In one preferred embodiment, the edge parts are formed over the entire peripheral edge of the seat cushion, that is, over the entire circumference. Note that in the seat cushion for a large motorcycle shown in FIG. 1C, the rear passenger seat part is separate from the other parts, but the passenger seat part also has an inverted U-shaped or C-shaped cross section in the left-right direction, and edge parts are formed on the left and right sides.

[0022] 2A-2B show examples of upper and lower dies for molding a seat cushion. This die is used to manufacture a seat cushion similar to that of FIG. 1A. FIG. 2A shows an upper die for molding the lower surface of the seat cushion, and FIG. 2B shows a lower die for molding the upper surface of the seat cushion. The lower surface side of the seat cushion in FIG. 1A is almost the same as the die surface of the upper die in FIG. 2A.

[0023] FIG. 3 is a plan view of the seat cushion when it is assumed to be flattened out, and shows several regions with different density and rigidity. This example corresponds approximately to the seat cushion in FIG. 1A and the molds in FIGS. 2A-2B. The edge portion 11, which has high density and rigidity, is provided over the entire periphery of the seat cushion 1. In the inner region other than the edge portion 11, the density and rigidity are relatively high in the pilot seat part 13 that supports the pilot's buttocks (particularly the vicinity of the ischial bones) from below, and the density and rigidity are relatively low in the pilot side portions 12 that sandwich the pilot seat part 13 from the left and right. The pilot side portions 12 may be the portions that come into contact with the pilot's thighs and knees.

[0024] A raised portion 13A is formed behind the pilot's seat 13 to support the pilot's buttocks (particularly the vicinity of the sacrum) from behind when the personal watercraft (PWC) rapidly accelerates. Further behind that, a co-pilot seat 13B is formed. The raised portion 13A and the co-pilot seat 13B can also have the same density and rigidity levels as the pilot's seat 13. The rear side portions 12A on the left and right of the raised portion 13A and the co-pilot seat 13B can also have the same density and rigidity levels as the pilot's side portions 12.

[0025] Fig. 4A shows a photograph of a vertical cross section taken along the center line of the central portion of the molded seat cushion 1. In the specific example of Fig. 4A, 4 to 6 vertically oriented sheet-like elastic bodies 1B, 1E, 1F, and 1H are stacked in the pilot seat portion 13. In addition, 7 to 10 vertically oriented sheet-like elastic bodies 1B to 1E, 1F, and 1H are stacked in the raised portion 13A behind the pilot seat portion.

[0026] Specifically, in the embodiment, as shown in FIG. 4A, a cut 14 is formed along the boundary between the pilot seat portion 13 and the raised portion 13A, cutting into the seat from above and below. This cut 14 is formed by protrusions 21B and 22B from the upper and lower dies 21, 22 shown in FIGS. 2A-2B. As can be seen from these figures, the cut 14 is slit-shaped and is formed in a broken line (intermittently) along a circular or elliptical arc in a plan view. This cut 14 makes it easy to form a hole through which a string for tying the cover to the seat cushion 1 is passed. In addition, the protrusions 21B and 22B from the upper and lower dies 21, 22 also play a role in preventing the sheet-like elastic body from being displaced during molding.

[0027] As shown in Figures 2A-2B, prior to molding, soft web-like sheet-like elastic bodies 1A and 1I can be attached so as to be located only near the protrusions 21B and 22B of the upper and lower dies 21, 22. In this way, the relatively small sheet-like elastic bodies 1A and 1I arranged to correspond to the center of the seat cushion 1 can be compressed relatively strongly during molding in the dies to form a hard surface layer. It is also believed that this contributes to preventing density deviations caused by local horizontal displacements, particularly in the centers of adjacent sheet-like elastic bodies 1H and 1B, during the initial stage of molding.

[0028] For these sheet-like elastic bodies 1A and 1I, the nonwoven fabric of "ELK" (registered trademark) can be used before being folded in an accordion shape. That is, for the sheet-like elastic bodies 1A and 1I arranged in the vicinity of the incisions 14 of the seat cushion 1 so as to be the uppermost and lowermost layers of the seat cushion 1, those that (1) are not vertically oriented and (2) have a smaller thickness than the other sheet-like elastic bodies 1B to 1H that are vertically oriented and have a thick plate (slab) shape can be used. These non-vertical type sheet-like elastic bodies 1A and 1I may not have a horizontal orientation along the sheet when manufactured, but may become horizontally oriented when compressed.

[0029] 4B shows a specific example of a method of laminating the sheet-shaped elastic bodies 1C to 1F and 1H in the center of the seat cushion 1. The sheet-shaped elastic bodies 1C to 1D are formed to be elongated in the left-right direction, and are arranged to correspond to the raised portion 13A. Of these, the sheet-shaped elastic body 1D is arranged only in the center in the left-right direction, and in the illustrated example, multiple sheets (particularly 2 to 4 sheets) are overlapped with their front-rear edges offset from each other. The sheet-shaped elastic body 1C has a larger left-right dimension than the sheet-shaped elastic body 1D, and extends left and right to the vicinity of the left and right edges of the seat cushion.

[0030] On the other hand, the sheet-like elastic body 1E extends left and right to the vicinity of the left and right edges of the seat cushion, similar to the sheet-like elastic body 1C, and covers from the pilot seat part 13 to the raised part 13A in the front-rear direction. In contrast, the sheet-like elastic body 1F extends from the vicinity of the front edge part 11 of the pilot seat part 13 to the vicinity of the rear edge of the co-passenger seat part 13B. In the illustrated example, a plurality of sheet-like elastic bodies 1F (especially 2 to 3 sheets) having the same dimensions and shape are arranged so as to be slightly shifted in the front-rear direction. As shown in Figs. 4A to 4B, the sheet-like elastic body 1E and the sheet-like elastic body 1F can be mutually interchanged in the stacking order, i.e., in the vertical direction (thickness direction).

[0031] In addition, since the vertically oriented sheet-like elastic bodies 1B to 1H are manufactured by folding them in an accordion shape, they are also oriented in one direction along the sheet surface. That is, they are oriented in the direction of the pleats when folded in an accordion shape. When the vertically oriented sheet-like elastic bodies 1B to 1H are stacked, the horizontal orientation directions can be made to be perpendicular or cross each other at an angle of 70° or more as appropriate. For example, in Figs. 4A to 4B, the sheet-like elastic bodies 1B, 1F and 1H can have fibers oriented in the front-rear direction of the seat cushion 1, and the sheet-like elastic bodies 1C to 1E can have fibers oriented in the left-right direction of the seat cushion 1. In addition, the sheet-like elastic body 1G described later can have fibers oriented in its length direction.

[0032] 4C to 4D show specific examples of lamination and molding methods for making edge portion 11 much higher in density and rigidity than other regions.

[0033] First, in each of Figs. 4C to 4D, the vertically oriented sheet-like elastic body 1H in contact with the upper die 21 and the vertically oriented sheet-like elastic body 1B in contact with the lower die 22 extend from the inside to the outside of the die 2 in the vicinity of the portion where the edge portion 11 is to be formed. Then, such protruding portions are sandwiched between the peripheral portion 21A of the upper die 21 and the peripheral portion 22A of the lower die 22 and are strongly compressed. As a result, during molding in the die, the sheet-like elastic bodies 1H and 1B are fixed at their peripheral portions so that they cannot shift in the horizontal direction. Therefore, the edge portion 11 with a uniform density can be reliably and easily formed.

[0034] As shown in Figs. 2A-2B, a groove formed on the inner edge of the peripheral portion 21A of the upper mold 21 engages with a rail-shaped protrusion formed on the inner edge of the peripheral portion 22A of the lower mold 22. The protruding portions of the sheet-like elastic bodies 1H and 1B, which are heated and strongly compressed by the peripheral portions 21A and 22A, can also function as a kind of sealant. In this way, even under the condition that the protruding portions of the sheet-like elastic bodies 1H and 1B are sandwiched, the inside of the mold can be sealed during molding, and the pressurized steam can be retained inside. After the molding is completed, the "burr"-like portions are cut and removed so as to cut out the molded product formed inside the mold 2.

[0035] In particular, the sheet-like elastic bodies 1H and 1B cover the entire surface of the seat cushion 1, and are located in the uppermost and lowermost layers in the mold 2, except for the non-vertical sheet-like elastic bodies 1A and 1I arranged only in the center of the seat cushion 1. Therefore, the sheet-like elastic bodies 1C and 1E sandwiched between these sheet-like elastic bodies 1H and 1B, particularly near the edge portions 11, are also fixed so as not to be displaced in the horizontal direction.

[0036] In the specific example of FIG. 4C, a long and narrow vertically oriented sheet-like elastic body 1G is arranged to extend along the edge portion 11 during molding using a mold. During molding, the sheet-like elastic body 1G is partially sandwiched directly between the peripheral portions 22A and 22B of the upper and lower molds on the peripheral side, or is sandwiched between the upper and lower sheet-like elastic bodies 1H and 1B extending to the outside of the mold 2, so that it is strongly compressed and fixed so that it cannot be displaced. Then, in this fixed state, it is laminated so that at least the inner side (the side opposite to the peripheral side) overlaps with the ends of the sheet-like elastic bodies 1C and 1E that extend into the edge portion 11. In this way, an edge portion 11 with a higher density and a uniform density can be easily formed.

[0037] Such an elongated sheet-like elastic body 1G for increasing the density of the edge portion 11 can be arranged over the entire or almost the entire periphery of the seat cushion 1, or can be arranged on a part of it. In one specific embodiment, it can be arranged on the left and right edges of the seat cushion 1, except for the front end and the rear end. As indicated by the thick curved arrow in FIG. 4C, the elongated sheet-like elastic body 1G can be inserted through the gap between the periphery portions 21A and 22A of the upper and lower dies just before the other sheet-like elastic bodies 1B to 1E and 1H are all set inside the die 2 and the die 2 is completely closed. In addition, the elongated sheet-like elastic body 1G can be set inside the die 2 in an "upright" state, that is, in a state inclined at 20° or more, 30° or more, or 40° or more with respect to the horizontal direction, as shown in FIG. 4C.

[0038] In the specific example of FIG. 4D, the vertically oriented sheet-like elastic body 1H in contact with the upper die 21 near the edge portion 11 is two-ply sheets of approximately the same size, and the edge portion of the sheet-like elastic body 1H that is not in direct contact with the upper die 21 is folded inward. The folded edge portion, i.e., the folded portion, is directly sandwiched between the peripheral portions 22A and 22B of the upper and lower dies on the peripheral side during molding, or is sandwiched between the sheet-like elastic bodies 1H and 1B extending to the outside of the die 2, so that it is strongly compressed and fixed so that it cannot be displaced. Then, in this fixed state, it is laminated by overlapping at least the inner side (the side opposite to the peripheral side) with the ends of the sheet-like elastic bodies 1C and 1E extending into the edge portion 11. In this way, the edge portion 11 having a higher density and a uniform density distribution can be easily formed.

[0039] In the above description, the longitudinally oriented sheet-like elastic bodies 1B to 1H are described as having the same thickness and the same density, but it is possible to use a plurality of types of thickness and density. For example, in the laminated structure shown in Figs. 4A to 4B, the sheet-like elastic bodies 1C to 1F and 1H may have the same thickness and density (for example, a basis weight of 1 kg / m 2 Among the vertically oriented elastic sheets, the elastic sheet 1B closest to the lower mold 22 (the uppermost layer side of the seat cushion 1) has a thickness or density smaller than those of the other vertically oriented elastic sheets 1C to 1F and 1H, for example, about half (for example, the basis weight is 0.5 kg / m 2 4C, the thickness or density of the elongated elastic sheet 1G for increasing the density of the edge portion 11 can be made larger than that of the main longitudinally oriented elastic sheets 1C to 1F and 1H, for example, about twice as large (for example, the basis weight is 2 kg / m 2 ) can be done.

[0040] In the above description, the non-vertical elastic sheet bodies 1A and 1I are described as being disposed only in the center of the seat cushion 1 in direct contact with the upper die 21 and the lower die 22, but they may be disposed over the entire surface, or may be disposed over only one of the upper die 21 and the lower die 22. Furthermore, the non-vertical elastic sheet bodies may be used by overlapping one covering the entire surface of the seat cushion 1 with one disposed only in the center.

[0041] Using FIG. 3, the density levels between regions have been explained. In a specific embodiment, the density can be set as follows (a) to (b), and can also be set as follows (b1) to (b2). (a) Edge part 11 40kg / m 3 , 43kg / m 3 , 45kg / m 3 , or 48 kg / m 3 or greater than 50 kg / m 3 That's it. (Note that the area having this density in the peripheral portion of the seat cushion 1 can also be called the edge portion 11.) Also, 150 kg / m 3 Below 120kg / m 3 or less than 100kg / m 3 below. (b) Other than the edge portion 11: Excluding the area close to the edge portion 11. For example, excluding areas within 2 cm, 5 cm, or 8 cm from the inner edge of the edge portion 11 having the above density range. 50kg / m 3 , 48kg / m 3 , 45kg / m 3 , 43kg / m 3 , 40kg / m 3 , 38kg / m 3 or 35 kg / m 3 Less than 10kg / m 3 More than 15kg / m 3 or more than 20kg / m 3 The end.

[0042] (b1) Pilot seat 13, raised portion 13A, and co-pilot seat 13B 20~35kg / m 3 , 23~32kg / m 3 , or 25-30kg / m 3 . (b2) Control side section 12 and rear side section 20~32kg / m 3 , 20~30kg / m 3 , or 23-26 kg / m 3 Alternatively, the density may be 70 to 97%, 80 to 95%, or 83 to 93% of the density of the pilot seat 13, etc.

[0043] In the above description of the density distribution, the pilot seat 13, the raised portion 13A, and the co-pilot seat 13B are described as having substantially the same density level, but the density can be stepped as appropriate. For example, the density of the raised portion 13A can be set to 103-110% or 103-108% of the density of the pilot seat 13. In this case, the co-pilot seat 13B can be set to the same density level as the raised portion 13A or the pilot seat 13.

[0044] In a preferred embodiment, the following fibers and conditions (1) to (8) can be used to manufacture a sheet-like elastic body ("Elk" (registered trademark) sheet).

[0045] (1) Fineness of skeletal fibers and fusible fibers: 1 to 200 dtex.

[0046] (2) Structure of skeletal fibers: They have a fiber cross-section that is solid, hollow, irregular, sheath-core, eccentric sheath-core, or side-by-side, and have two-dimensional zigzag crimps or three-dimensional helical or omega crimps.

[0047] (3) Skeleton fiber and core component resin of fusible fiber: Short fibers made of polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polytetramethylene terephthalate, poly-1,4-dimethylcyclohexane terephthalate, polypivalolactone, or polyester copolymerized with a third component, or a blend of these fibers, or composite fibers made of two or more of the above polymer components, etc.

[0048] (4) Composition of sheath component resin (fusion resin): thermoplastic polyester-ether elastomer. More specifically, it is a polyester-ether block copolymer having a copolymerization ratio (weight ratio) of hard segment component to soft segment component of 95:5 to 20:80, the hard segment component being a polyester having a main acid component of 40 to 100 mol % terephthalic acid and 0 to 50 mol % isophthalic acid and a main glycol component of 1,4-butanediol, and the soft segment component being a polyether, which is a poly(alkylene oxide) glycol having an average molecular weight of 400 to 5000.

[0049] (5) Intrinsic viscosity of sheath component resin (fusion resin): 0.8 to 1.7 dl / g, particularly 0.9 to 1.5 dl / g. (6) Core-sheath area ratio in the cross section of the fusible fiber: 20 / 80 to 80 / 20. (7) Melting point of sheath component resin (fusion resin): lower than the melting points of skeletal fiber and core component resin by 40° C. or more. When the skeletal fiber and core component resin are polyethylene terephthalate (melting point: 250 to 270° C.), the melting point of the sheath component resin is, for example, 120 to 200° C., or 130 to 180° C.

[0050] (8) Mixing weight ratio of skeletal fiber to fusible fiber: 90 / 10 to 10 / 90.

[0051] In a preferred embodiment, the thermoplastic elastomer forming the sheath (fusible resin) of the fusible fiber has the following characteristics (9) to (10) when a sheet tensile test is performed in accordance with JIS K6273:2018 "Vulcanized rubber and thermoplastic rubber - Determination of tensile set, elongation and creep rate" and JIS K6251:2017 "Vulcanized rubber and thermoplastic rubber - Determination of tensile properties". (9) Recovery rate from (300±10)% elongation (100-constant elongation permanent tensile set (%)): 60% or more, preferably 70% or more, for example, 70 to 90%. (10) Elongation at break: 500% or more, preferably 800% or more, for example, 800 to 1200%.

[0052] In a preferred embodiment, molding of the sheet-like elastic body in a mold can be carried out under the following condition (11), and the molded seat cushion has the following properties (12) to (14). (11) Heating during molding: Pressurized steam is introduced into the mold all at once to rapidly heat the material to a temperature 3 to 10°C or 3 to 8°C higher than the melting point of the sheath of the fusible fiber, and maintain that temperature. For example, steam at 5 to 20 atmospheres is introduced.

[0053] (12) Density distribution range: 15-150kg / m 3 45~120kg / m at the edge 3 15~40kg / m except for edges 3 . (13) Compression hardness (JIS K 6400-2:2012) - Area excluding edges and their vicinity When measured with a compression plate size of 200φ and a compression speed of 100mm / min, the pressure side load at a constant compression of 40% is 200~500N or 300~400N. At a constant compression of 25%, the pressure side load is 400~800N or 500~700N.

[0054] (14) Durometer A hardness (JIS K 7215:1986) - Edge part According to JIS K 7215 "Durometer hardness testing method for plastics", the durometer A hardness is approximately 25 to 75 (A25 to A75). Durometer A hardness is the density of 100 kg / m 3 and density is 50kg / m 3 At a density of 100 kg / m 3 When the above-mentioned compression hardness (JIS K 6400-2:2012) was measured for this area, it appeared to be significantly greater than 1000N.

[0055] <Example> A seat cushion 1 having the laminated structure shown in Figures 4A and 4C was manufactured.

[0056] The sheet-like elastic bodies 1A to 1I used in the production are all "ELK" (registered trademark), a commercial product of Teijin Frontier Co., Ltd., or vertical-type nonwoven fabric, and are incorporated into various products manufactured and sold by Teijin Frontier Co., Ltd.

[0057] The non-vertical sheet-like elastic bodies 1A and 1I have a basis weight of 0.15 kg / m 2 The vertical elastic sheet bodies 1B to 1H are made of nonwoven fabric of "ELK" (registered trademark) with a basis weight of 0.45 kg / m 2 However, for the sheet-like elastic bodies 1C to 1F and 1H, two sheets were overlapped and slightly compressed (with a basis weight of about 1 kg / m 2 ) was used, and the sheet-like elastic body 1B was a single sheet that was slightly compressed (weight per unit area was 0.5 kg / m 2 ) was used, and the elongated sheet-like elastic body 1G for increasing the density of the edge portion 11 was made by overlapping two sheets and slightly compressing them (with a basis weight of about 2 kg / m 2 The vertical elastic sheets 1B to 1H used here were obtained by folding the nonwoven fabric of "ELK" (registered trademark) in an accordion shape, similar to the non-vertical elastic sheets 1A and 1I.

[0058] The sheet-like elastic bodies 1A to 1I used in the production had the production conditions or characteristics described below in (1) to (10). (1) Fineness of skeletal fiber: 13 dtex. Fineness of fusible fiber: 6.6 dtex.

[0059] (2) Structure of skeletal fiber: hollow cross section, three-dimensional Ω-shaped three-dimensional crimped shape.

[0060] (3) Resin constituting the skeletal fiber and the core component of the fusible fiber: polyethylene terephthalate.

[0061] (4) Composition of sheath resin (fusion resin): Thermoplastic polyester-ether elastomer. More specifically, it is a block copolymer with isophthalic acid copolymerized polybutylene terephthalate as the hard segment and polytetramethylene glycol as the soft segment.

[0062] (5) Intrinsic viscosity of sheath component resin (fusion resin): 1.15 dl / g. (6) The core-sheath area ratio in the cross section of the fusible fiber: core / sheath=60 / 40. (7) Melting point of sheath component resin (fusion resin): 155°C.

[0063] (8) Mixing weight ratio of skeletal fiber to fusible fiber: 30 / 70.

[0064] When a sheet-like tensile test is performed on the thermoplastic elastomer constituting the sheath component resin (fusible resin) of the fusible fiber in accordance with JIS K6273:2018 "Vulcanized rubber and thermoplastic rubber," the sheet has the following characteristics (9) to (10). (9) Recovery rate from (300±10)% elongation: 70-90%. (10) Breaking elongation: 1000%.

[0065] The sheet-like elastic body was molded in a mold under the conditions of (11) below. The molded seat cushion had the following properties of (12) to (14). (11) Heating during molding: Pressurized steam at 10 atmospheres was suddenly introduced into the mold 2 to heat it to 160°C and maintain it for a while.

[0066] (12) Density distribution range: 20-100kg / m 350 to 100 kg / m at the edge 11 3 26 to 28 kg / m for the pilot seat 13 and the co-pilot seat 13B 3 27~29kg / m at raised part 13A 3 26 to 28 kg / m in the steering side section 12 and the rear side section 12A 3 .

[0067] (13) Hardness (JIS K6400-2:2012) measurement The seat cushion before the skin was attached was used as a test specimen as it was, and measurements were taken with a compression plate size of 200φ and a compression speed of 100 mm / min. The results shown in Table 1 below were obtained.

[0068] JPEG0007630326000001.jpg36170

[0069] (14) Evaluation of drainage The time required for drainage, as evaluated by the measurement method described below, was 24 hours.

[0070] The seat cushion 1 was covered entirely with a support base as a lid and a skin fixed thereto. The skin here was made of a water-impermeable material (raw cloth) obtained by soaking a polyester (PET) knitted fabric in polyurethane resin. This skin was formed by sewing together a plurality of skin pieces cut out from the raw cloth at locations corresponding to the ridges and valleys of the seat cushion 1. The skin had a string-through hole for fixing the skin along the cut 14 in the center of the seat cushion 1, and a string was passed through this location to fasten the skin, seat cushion 1, and support base together. The seat cushion 1 with the skin and support base thus provided with a plurality of fastening holes and sewing holes was completely immersed in water for 24 hours. Then, it was pulled out of the water and placed on a weighing scale, and the time required for the amount of water that had soaked in to decrease to 10% was determined based on the weight change thereafter.

[0071] It took 2 hours for the amount of water to decrease by 80%. Also, 120 hours (5 days) after it was taken out of the water, the weight had almost returned to the weight before it was immersed in water, and it was confirmed that the water had been almost completely removed.

[0072] As a comparative example, we tested the drainage of a seat cushion (current product of "Yamaha FX") made of a general soft urethane resin foam in the same way. Even after 144 hours (6 days), the amount of water that had soaked in had only decreased to 14%. Furthermore, even after leaving it on a weighing scale for 30 days, there was almost no change in weight and the water did not come out.

[0073] The seat cushion of this comparative example has a nearly uniform density and rigidity. Therefore, in order to prevent the edge portion from being pulled inward when attaching the skin, it was necessary to set a fastening method that would not apply such force to the edge portion. For example, as shown in the left end of Fig. 1A, it was necessary to sew together the skin piece on the upper surface side and the skin piece covering the end surface of the edge portion as separate pieces.

Claims

1. A seat cushion having an edge portion for use in a seat of a saddle-ride type vehicle, The seat cushion has a three-dimensional fiber structure formed by heat-sheathing a core-sheath type fusible fiber and a skeletal fiber at the intersections of the fibers, The sheath of the fusible fiber is formed from a polyester polyether elastomer or other thermoplastic elastomer; This thermoplastic elastomer is unevenly distributed at the fusion points between the fibers, forming bulges at each fusion point. The skeletal fiber and the core of the fusible fiber are formed from a non-elastomer resin, The skeletal fiber is a bulky fiber that has been subjected to a crimping treatment, The fineness of the skeletal fiber and the fusible fiber is within the range of 1 to 200 dtex, the seat cushion has a laminated structure in which a plurality of layers, each having the three-dimensional fiber structure, are fused to each other, the seat cushion has a density distribution due to the laminated structure in each part of the seat cushion, and has a rigidity distribution that depends on this density distribution; The plurality of layers forming the laminated structure include at least one of each of the following c1 to c2, or at least one of each of the following c1 to c3. (c1) Extending over the entire surface of the seat cushion. (c2) Extending from the cockpit to the raised area behind it. (c3) Those placed only on the raised rear part.

2. A seat cushion having an edge portion for use in a seat of a saddle-ride type vehicle, The seat cushion has a three-dimensional fiber structure formed by heat-sheathing a core-sheath type fusible fiber and a skeletal fiber at the intersections of the fibers, The sheath of the fusible fiber is formed from a polyester polyether elastomer or other thermoplastic elastomer; This thermoplastic elastomer is unevenly distributed at the fusion points between the fibers, forming bulges at each fusion point. The skeletal fiber and the core of the fusible fiber are formed from a non-elastomer resin, The skeletal fiber is a bulky fiber that has been subjected to a crimping treatment, The fineness of the skeletal fiber and the fusible fiber is within the range of 1 to 200 dtex, the seat cushion has a laminated structure in which a plurality of layers, each having the three-dimensional fiber structure, are fused to each other, the seat cushion has a density distribution due to the laminated structure in each part of the seat cushion, and has a rigidity distribution that depends on this density distribution; A seat cushion for a saddle-ride type vehicle, which requires 36 hours or less for water to drain as evaluated by the following measurement method. A seat cushion is entirely covered with a support base as a lid and a skin fixed to the support base, and the skin is made of a water-impermeable sheet material and has a number of string holes or sewing holes. The seat cushion is then completely immersed in water for 24 hours, and the time required for the amount of soaked water to decrease to 10% is determined based on the change in weight after being pulled out.

3. At least one of the layers of the laminated structure extends to a periphery of the seat cushion; 3. The seat cushion for a saddle-ride type vehicle according to claim 1, wherein the plurality of layers forming the laminated structure includes a plurality of layers having longitudinally oriented fibers oriented in a thickness direction.

4. A seat cushion having an edge portion for use in a seat of a saddle-ride type vehicle, The seat cushion has a three-dimensional fiber structure formed by heat-sheathing a core-sheath type fusible fiber and a skeletal fiber at the intersections of the fibers, The sheath of the fusible fiber is formed from a polyester polyether elastomer or other thermoplastic elastomer; This thermoplastic elastomer is unevenly distributed at the fusion points between the fibers, forming bulges at each fusion point. The skeletal fiber and the core of the fusible fiber are formed from a non-elastomer resin, The skeletal fiber is a bulky fiber that has been subjected to a crimping treatment, The fineness of the skeletal fiber and the fusible fiber is within the range of 1 to 200 dtex, the seat cushion has a laminated structure in which a plurality of layers, each having the three-dimensional fiber structure, are fused to each other, the seat cushion has a density distribution due to the laminated structure in each part of the seat cushion, and has a rigidity distribution that depends on this density distribution; At least one of the layers of the laminated structure extends to a periphery of the seat cushion; The multiple layers forming the laminated structure include multiple vertically oriented layers in which fibers are oriented in the thickness direction, and at least one non-vertically oriented layer, and this at least one non-vertically oriented layer has the same three-dimensional fiber structure as the vertically oriented layer.

5. A seat cushion for a saddle-type vehicle as described in any one of claims 1 to 3, wherein the multiple layers forming the laminated structure include at least one non-vertically oriented layer.

6. The seat cushion for a saddle-ride type vehicle according to any one of claims 1 to 5, wherein the edge portion is a portion provided along at least a part of the periphery of the seat cushion that is thinner than other regions, or a portion whose thickness tapers toward the periphery.

7. The seat cushion for a saddle-ride type vehicle according to any one of claims 1 to 6, wherein the edge portion has a higher density and rigidity than other areas, and the seat cushion has at least two areas other than the edge portion having different density levels.

8. The edge portion has a density of 40 kg / m 3 8. The seat cushion for a saddle-ride type vehicle according to claim 7, further comprising a shape-retaining frame for retaining the shape of the seat cushion.

9. The density is 40 kg / m except for the edge part. 3 The seat cushion for a saddle-ride type vehicle according to claim 8, wherein the seat cushion is smaller than

10. Density is 20 to 35 kg / m except for the edge part. 3 is within the range of 10. A seat cushion for a saddle-ride type vehicle as described in claim 9, wherein the at least two regions are a pilot's seat portion that supports and holds the pilot from below, a side portion that contacts the insides of the pilot's legs, or a raised portion behind the pilot's seating position, and the density of the pilot's seat portion is smaller than the density of the side portion or the density of the raised portion.

11. 11. The seat cushion for a saddle-ride type vehicle according to claim 1, wherein the skeletal fibers are hollow fibers crimped into a curved shape, and the fusible fibers have a fineness smaller than that of the skeletal fibers.

12. The seat cushion for a saddle-ride type vehicle according to any one of claims 1 to 11, wherein the plurality of vertically oriented layers included in the laminated structure all have a horizontal orientation, and are arranged such that the horizontal orientation directions are perpendicular to each other or parallel to each other.

13. A saddle-ride type vehicle having a seat cushion according to any one of claims 1 to 12.

14. The cover that covers the seat cushion, A support base on which the seat cushion is placed; a string or thread used at least in part to fasten the skin to the support; 14. The saddle-ride type vehicle of claim 13, wherein the support platform defines a flip-up lid for a machinery or storage compartment.

15. 15. The saddle-ride type vehicle according to claim 13 or 14, which is a personal watercraft or a motorcycle.

16. A method for manufacturing a seat cushion having an edge portion for use in a seat of a saddle-ride type vehicle, comprising the steps of: A fiber made of a non-elastomer resin is subjected to a crimping process to prepare a skeletal fiber as a bulky fiber, and a core-sheath type fusible fiber is prepared by covering a core made of a non-elastomer resin with a sheath formed of a polyester / polyether elastomer or other thermoplastic elastomer, wherein the fineness of the skeletal fiber and the fusible fiber is within a range of 1 to 200 dtex, A core-sheath type fusible fiber and a skeletal fiber are mixed in the state of short fibers and heated to form a sheet-like elastic body having a three-dimensional fiber structure in which the fibers are thermally fused at their intersections, and at this time, the thermoplastic elastomer forming the sheath of the fusible fiber is unevenly distributed at the fusion points between the fibers to form bulging portions at each of the fusion points, In this case, in order to obtain a sheet-like elastic body having longitudinally oriented fibers oriented in the thickness direction, the sheet-like elastic body before being longitudinally oriented is folded in an accordion-like manner and then heat-sealed to each other. The plurality of sheet-like elastic bodies thus obtained are stacked together, and in a mold, the sheet-like elastic bodies are fused together by applying pressure and heat thereto, and a seat cushion is formed along the inner surface of the mold. At this time, the plurality of sheet-like elastic bodies include a plurality of vertically oriented ones, A density distribution is formed depending on the degree of compression in the mold for each part of the seat cushion, as well as the density, thickness, and number of layers of the sheet-like elastic body, and a rigidity distribution is also formed depending on the density distribution. The method for manufacturing a seat cushion for a saddle-type vehicle, wherein the vertical sheet-like elastic body includes at least one of the following c1 to c2, or at least one of the following c1 to c3: (c1) Extending over the entire surface of the seat cushion. (c2) Extending from the cockpit to the raised area behind it. (c3) Those placed only on the raised rear part.

17. The method for manufacturing a seat cushion for a saddle-ride type vehicle according to claim 16, wherein a laminated structure derived from at least one of the following d1 to d3 is formed. (d1) The sheet-like elastic bodies of c1 are overlapped with each other, and one of them is folded back along the edge of the side portion of the seat cushion. (d2) A long, thin sheet-shaped elastic body is disposed along the edge of the side portion of the seat cushion, and is compressed and fused so that its width direction is oriented nearly vertically. (d3) In order to form the raised rear portion, elongated sheet-shaped elastic bodies extending in the width direction of the seat cushion are placed only in this area and are overlapped so that their positions in the front-to-rear direction of the seat cushion are shifted relative to each other.

18. A method for manufacturing a seat cushion having an edge portion for use in a seat of a saddle-ride type vehicle, comprising the steps of: A fiber made of a non-elastomer resin is subjected to a crimping process to prepare a skeletal fiber as a bulky fiber, and a core-sheath type fusible fiber is prepared by covering a core made of a non-elastomer resin with a sheath formed of a polyester / polyether elastomer or other thermoplastic elastomer, wherein the fineness of the skeletal fiber and the fusible fiber is within a range of 1 to 200 dtex, A core-sheath type fusible fiber and a skeletal fiber are mixed in the state of short fibers and heated to form a sheet-like elastic body having a three-dimensional fiber structure in which the fibers are thermally fused at their intersections, and at this time, the thermoplastic elastomer forming the sheath of the fusible fiber is unevenly distributed at the fusion points between the fibers to form bulging portions at each of the fusion points, In this case, in order to obtain a sheet-like elastic body having longitudinally oriented fibers oriented in the thickness direction, the sheet-like elastic body before being longitudinally oriented is folded in an accordion-like manner and then heat-sealed to each other. The plurality of sheet-like elastic bodies thus obtained are stacked together, and in a mold, the sheet-like elastic bodies are fused together by applying pressure and heat thereto, and a seat cushion is formed along the inner surface of the mold. At this time, the plurality of sheet-like elastic bodies include a plurality of vertically oriented ones, A density distribution is formed depending on the degree of compression in the mold for each part of the seat cushion, as well as the density, thickness, and number of layers of the sheet-like elastic body, and a rigidity distribution is also formed depending on the density distribution. A method for manufacturing a seat cushion for a saddle-ride type vehicle, wherein a plurality of sheet-like elastic bodies fused to each other in a mold includes at least one non-vertical one.

19. The method for manufacturing a seat cushion for a saddle-ride type vehicle according to any one of claims 16 to 18, wherein the edge portion has a higher density and rigidity than other regions, and at least two regions other than the edge portion have different density levels.

20. The edge portion has a density of 40 kg / m 3 It is larger than the seat cushion and has a shape-retaining frame to maintain the shape of the seat cushion. The density is 40 kg / m except for the edge part. 3 The method for manufacturing a seat cushion for a saddle-ride type vehicle according to any one of claims 16 to 19, wherein the width of the seat cushion is smaller than the width of the saddle-ride type vehicle seat cushion.

21. 21. The method for manufacturing a seat cushion for a saddle-ride type vehicle according to claim 16, wherein the skeletal fibers are hollow fibers crimped into a curved shape, and the fusible fibers have a fineness smaller than that of the skeletal fibers.

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