Vehicle seat base material and vehicle seat

Abstract

To provide a vehicle seat base material that has proper cushioning properties (comfort to sit on) and that can inhibit a submarine phenomenon when an impact is generated due to vehicular crash, sudden braking and the like, and a vehicle seat.SOLUTION: In a vehicle seat 10 in which a cushion material 21 is overlaid on a vehicle seat base material 11, the vehicle seat base material 11 comprises a front-side part 13 for being pressurized by the back side of a seated person's knee, and a rear-side part 15 for being pressurized by the seated person's buttocks. The front-side part 13 and the rear-side part 15 are made of a resin foam. The resin foam of the front-side part 13 is harder than that of the rear-side part 15.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vehicle seat base material and a vehicle seat. [Background technology]

[0002] A base material on which a cushioning material is laminated is used as a vehicle seat. In order to reduce the weight of the vehicle seat, the base material is made of a hard foam (preferably having a specific gravity of 0.1 to 0.25 (density of 100 to 250 kg / m)) instead of a metal frame. 3 ) has been proposed (Patent Document 1). Another vehicle seat proposed is one in which a soft foam portion is laminated onto a hard foam portion made of expanded polypropylene (Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3474571 [Patent Document 2] Patent No. 4503020 Publication Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional vehicle seats, in order to prevent the occupant from sliding forward off the seating surface in the event of an impact such as a vehicle collision or sudden braking, known as the "submarining phenomenon," some vehicle seats have a lightweight, high-hardness vehicle seat base material (raising material) placed under the cushioning material that takes advantage of the hardness of expanded polypropylene (EPP) to provide anti-submarining performance.

[0005] However, since foamed polypropylene is a hard material, by making the part of the vehicle seat that the back of the knees contact harder, it is possible to ensure anti-submarining performance, but there is a problem that the buttocks are uncomfortable to sit on.

[0006] The present invention has been made in consideration of the above-mentioned points, and aims to provide a vehicle seat base material and a vehicle seat that are comfortable for the buttocks and can suppress the submarine phenomenon when an impact occurs due to a vehicle collision, sudden braking, etc. [Means for solving the problem]

[0007] The first aspect is characterized in that a vehicle seat base material on which cushioning material is laminated has a front portion that is pressed by the back of the knees of a seated occupant and a rear portion that is pressed by the buttocks of the seated occupant, the front portion and the rear portion being made of resin foam, and the resin foam of the front portion being harder than the resin foam of the rear portion.

[0008] A second aspect is characterized in that in the first aspect, the resin foam of the front portion satisfies any one of the following 1) to 4). 1) 2% compression hardness is 100-5000N, 2) 5% compression hardness is 200-8000N, 3) 10% compression hardness is 300~12000N, 4) Asker C hardness: 15 to 100 degrees

[0009] The third aspect is characterized in that, in the first or second aspect, the difference in hardness between the resin foam of the front portion and the resin foam of the rear portion satisfies any of the following 1) to 4). 1) 2% compression hardness difference is 50~4900, 2) 5% compression hardness difference is 100~7800N, 3) 10% difference in compression hardness is 150~11700N 4) Asker C hardness difference is 5 to 85 degrees

[0010] A fourth aspect is any one of the first to third aspects, characterized in that the resin foam of the rear portion satisfies any one of the following 1) to 4). 1) 2% compression hardness is 20 to less than 100N, 2) 5% compression hardness is 40 to less than 200N, 3) 10% compression hardness is 60 to less than 300N, 4) Asker C hardness is between 2 and 20 degrees

[0011] A fifth aspect is a vehicle seat in which a cushioning material is laminated to a vehicle seat base material, the vehicle seat base material being any one of the vehicle seat base materials of the first to fourth aspects, and the cushioning material being made of urethane foam.

[0012] A sixth aspect is the fifth aspect, characterized in that the resin foam in the rear portion is harder than the cushion material. Effect of the Invention

[0013] In the present invention, the vehicle seat base material on which the cushioning material is laminated has a front portion that is pressed by the backs of the knees of the seated person and a rear portion that is pressed by the buttocks of the seated person, the front and rear portions are resin foam, and the resin foam of the front portion is harder than the resin foam of the rear portion, so that in a seated state, the rear portion that is pressed by the buttocks and the vicinity thereof sinks more than the front portion that is pressed by the backs of the knees and the vicinity thereof, and when an impact occurs due to a vehicle collision or sudden braking, the seated person in the seat is less likely to slide forward from the seating position on the seat surface, thereby preventing the occurrence of the submarine phenomenon. Also, the seating comfort of the buttocks can be improved. [Brief description of the drawings]

[0014] [Figure 1] 1 is a cross-sectional view of an example of a vehicle seat. [Diagram 2] 4 is a cross-sectional view of a mold showing a process for molding a vehicle seat base material. FIG. [Diagram 3] 1 is a table showing the configurations and physical properties of comparative examples and examples of vehicle seat base materials. [Figure 4] 11 is a table showing the measurement results of the configuration, physical properties, and load for the comparative example and the example of the rear side portion of the vehicle seat. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings, in which: FIG.

[0016] The vehicle seat base material 11 comprises a front portion 13 that is pressed against the back of the knees of the seated occupant and the vicinity thereof, and a rear portion 15 that is pressed against the buttocks of the seated occupant and the vicinity thereof, the thickness of the front portion 13 being greater than the thickness of the rear portion 15, and the upper surface 15a of the rear portion 15 being recessed and lower than the upper surface 13a of the front portion 13.

[0017] The boundary position 17 between the front portion 13 and the rear portion 15 is near the midpoint between the front and rear of the vehicle seat base material 11, preferably further forward than the midpoint. Specifically, when the front-to-rear length of the vehicle seat base material 11 is L, the distance L1 from the front end 11a of the vehicle seat base material 11 to the boundary position 17 is preferably L / 2 to L / 5.

[0018] The groove 16 formed on the seat surface side (upper side) of the boundary position 17 between the front portion 13 and the rear portion 15 is a groove formed by a partition plate 55 erected on a mold surface 55 of a lower mold 51 of a mold 50 shown in Fig. 2 when the front portion 13 and the rear portion 15 are integrally manufactured by molding, which will be described later. The groove 16 is not always formed, and may not be formed, for example, when the front portion 13 and the rear portion 15 are integrated by another molding method.

[0019] The front portion 13 and the rear portion 15 are made of a resin foam, and the resin foam of the front portion 13 is harder than the resin foam of the rear portion. The front portion 13 of this embodiment is made of a semi-rigid or rigid resin foam. Examples of the semi-rigid resin foam include semi-rigid urethane foam, and examples of the rigid resin foam include rigid urethane foam and foamed polypropylene. Furthermore, from the viewpoint of preventing the submarine phenomenon, it is preferable that the thickness of the resin foam in the front portion 13 is thicker than that of the resin foam in the rear portion. In particular, it is preferable that the thickness of the resin foam in the below-knee portion of the front portion 13 is thicker than that of the resin foam in the below-buttocks portion of the rear portion. Also, it is preferable that the position of the resin foam in the front portion 13 that comes into contact with the cushioning material in the below-knee portion is higher than the position of the resin foam in the rear portion that comes into contact with the cushioning material in the below-buttocks portion, and that it is located on the surface side of the cushioning material.

[0020] Semi-rigid urethane foam is a foam having elastic recovery between soft urethane foam with good elastic recovery and rigid urethane foam without elastic recovery. Since semi-rigid urethane foam has elasticity, by forming the front portion 13 of the vehicle seat base material 11 from semi-rigid urethane foam, when the front portion 13 is pressed against the back of the knees and the vicinity thereof when the seated person sits down, the front portion 13 elastically deforms, improving the feel given to the back of the knees in the initial stage of sitting.

[0021] The resin foam constituting the front portion 13 has a density (in accordance with JIS K 7222) of 30 to 70 kg / m 3 is preferred. The density of the resin foam constituting the front portion 13 is set to 30 to 70 kg / m 3 This can increase the weight of the vehicle seat base material 11. Furthermore, by providing a recess in the resin foam constituting the front portion 13 and providing a space in the recess, the weight can be further reduced. Also, a recess may be provided in the resin foam constituting the rear portion 13.

[0022] The resin foam constituting the front portion 13 preferably satisfies any one of the following 1) to 4) in order to prevent the submarining phenomenon, in which a seated occupant slides forward from the seating surface in the event of a vehicle collision, and more preferably satisfies two or more of 1) to 4) in order to prevent the submarining phenomenon over a wide range of vehicle collision levels, regardless of whether the vehicle is seriously or not. It is even more preferable for the resin foam constituting the front portion 13 to satisfy all of the following. 1) 2% compression hardness is 100-5000N, 2) 5% compression hardness is 200-8000N, 3) 10% compression hardness is 300~12000N, 4) Asker C hardness: 15 to 100 degrees

[0023] By setting the 2% compression hardness, 5% compression hardness and Asker C hardness of the resin foam constituting the front portion 13 to any one of the following values ​​1), 2) and 4), the feeling given to the back of the knees and the surrounding area at the initial stage of sitting can be made better and more suitable. 1) 2% compression hardness is 100-1200N, 2) 5% compression hardness is 200-2000N, 4) Asker C hardness: 15 to 50 degrees Furthermore, by setting the 10% compression hardness of the resin foam constituting the front portion 13 to a value of 300 to 2500 N, it is possible to provide good cushioning to the backs of the knees and the surrounding areas when seated without feeling like the knees are bottoming out.

[0024] The compression hardness test method was to compress a test sample (100mmt x 400mm x 400mm) with a pressure plate without pre-compression at a compression speed of 50mm / min until the load reached 1000N, and then release the compression with the pressure plate at a speed of 50mm / min to obtain a load-deflection curve. The load at 2% compression was defined as the 2% compression hardness, the load at 5% compression as the 5% compression hardness, and the load at 10% compression as the 10% compression hardness. The pressure plate used had a diameter of 100mm.

[0025] The Asker C hardness was measured by using an Asker C hardness tester (pressure surface height: 2.54 mm, diameter 5.08 mm) and measuring the hardness by contacting the pressure surface of the test sample.

[0026] The resin foam constituting the front portion 13 is harder than the resin foam constituting the rear portion 15, and preferably has higher hardnesses of 2% compression hardness, 5% compression hardness, 10% compression hardness and Asker C hardness, and more preferably has higher hardnesses of all of them. By making the compression hardness and Asker C hardness of the front portion 13 higher than those of the rear portion 15, the rear portion 15, which is pressed at the buttocks and the vicinity thereof, sinks more when seated than the front portion 13, which is pressed at the backs of the knees and the vicinity thereof, and the synergistic effect of this difference in thickness between the front portion 13 and the rear portion 15 makes it possible to more effectively prevent the submarine phenomenon from occurring.

[0027] The resin foam constituting the rear portion 15 preferably satisfies any one of the following 1) to 4), more preferably satisfies a combination of 1) to 4), and even more preferably satisfies all of 1) to 4). 1) 2% compression hardness is 20 to less than 100N, 2) 5% compression hardness is 40 to less than 200N, 3) 10% compression hardness is 60 to less than 300N, 4) Asker C hardness is between 2 and 20 degrees

[0028] From the viewpoint of preventing the submarine phenomenon, it is preferable that the difference in hardness between the resin foam constituting the front portion 13 and the resin foam constituting the rear portion 15 satisfies any one of the following 1) to 4), more preferably satisfies two or more of 1) to 4), and even more preferably satisfies all of 1) to 4). 1) 2% difference in compression hardness is 50~4900N, 2) 5% compression hardness difference is 100~7800N, 3) 10% difference in compression hardness is 150~11700N 4) Asker C hardness difference is 5 to 85 degrees In addition, from the viewpoint of the feeling around the back of the knees at the beginning of sitting, and the cushioning and bottoming out around the back of the knees in the seated state, it is preferable that the difference in hardness between the resin foam constituting the front portion 13 and the resin foam constituting the rear portion 15 satisfies any one of the following 1) to 4), more preferably satisfies two or more of 1) to 4), and even more preferably satisfies all of 1) to 4). 1) 2% difference in compression hardness is 40~1150N, 2) 5% compression hardness difference is 80~1900N, 3) 10% difference in compression hardness is 120~2300N 4) Asker C hardness difference is 4 to 45 degrees

[0029] By setting the 2% compression hardness of the resin foam constituting the rear portion 15 to less than 20 to 100 N, the 5% compression hardness to less than 40 to 200 N, and the Asker C hardness to less than 2 to 20 degrees, the feel given to the buttocks and surrounding areas at the initial stage of sitting can be made good. By setting the 10% compression hardness of the resin foam constituting the rear portion 15 to less than 60-300 N, the flexibility in the seated state is improved, the bottoming out feeling in and around the buttocks is reduced, and the cushioning properties are improved. In addition, in the seated state, the rear portion 15, which is pressed by the buttocks, sinks more, and the occurrence of the submarine phenomenon can be more effectively prevented. The resin foam constituting the rear portion 15 is preferably made harder than the cushion material 21 laminated on the vehicle seat base material 10 so as to be able to support the cushion material 21 when seated.

[0030] The method for testing the compression hardness and the method for measuring the Asker C hardness of the resin foam constituting the rear portion 15 are similar to the method for testing the compression hardness and the method for measuring the Asker C hardness of the resin foam constituting the front portion 13.

[0031] The resin foam constituting the rear portion 15 has a density (in accordance with JIS K 7222) of 30 to 70 kg / m 3 is preferred. The density of the resin foam constituting the rear portion 15 is set to 30 to 70 kg / m 3This allows the vehicle seat base material 11 to be made lighter.

[0032] In this embodiment, the resin foam constituting the rear portion 15 is made of soft urethane foam. Soft urethane foam is a foam with good elastic recovery. Since soft urethane foam has better elasticity than semi-rigid or rigid resin foam, by forming the rear portion 15 of the vehicle seat base material 11 from soft urethane foam, the rear portion 15 sinks more when seated, suppressing the occurrence of the submarine phenomenon, and eliminating the feeling of bottoming out in and around the buttocks, thereby providing good cushioning.

[0033] The following describes the case where the front portion 13 is made of semi-rigid or rigid urethane foam, and the rear portion 15 is made of flexible urethane foam. The semi-rigid or rigid urethane foam constituting the front portion 13 and the flexible urethane foam constituting the rear portion 15 are both obtained by mixing urethane foam raw materials containing polyol, polyisocyanate, a blowing agent, and a catalyst, and reacting the polyol with the isocyanate.

[0034] The polyol may be a polyhydric alcohol or a polyol having an alkylene oxide such as ethylene oxide (EO) or propylene oxide (PO) added thereto, and a polyol for polyurethane foam may be used. For example, any of polyether polyol, polyester polyol, polyether ester polyol, and polymer polyol may be used, and one or more of these may be used.

[0035] Examples of polyether polyols include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, neopentyl glycol, glycerin, pentaerythritol, trimethylolpropane, sorbitol, sucrose, and the like, as well as polyether polyols in which alkylene oxides such as ethylene oxide (EO) and propylene oxide (PO) are added to these polyhydric alcohols.

[0036] Examples of polyester polyols include polyester polyols obtained by polycondensation of an aliphatic carboxylic acid such as malonic acid, succinic acid, or adipic acid, or an aromatic carboxylic acid such as phthalic acid, and an aliphatic glycol such as ethylene glycol, diethylene glycol, or propylene glycol. Examples of the polyether ester polyol include those obtained by reacting the above-mentioned polyether polyol with a polybasic acid to form a polyester, and those having both polyether and polyester segments in one molecule.

[0037] The polymer polyol is a polyol in which polyacrylonitrile or polystyrene is dispersed.

[0038] Of the polyols for semi-rigid urethane foams, the polyol (main polyol) used in an amount of 5 parts by weight or more is preferably a polyether polyol or polymer polyol having a molecular weight of 500 to 8000, a functionality of 2 to 6, and a hydroxyl value of 14 to 700 mgKOH / g. As the polyol for rigid urethane foam, a polyether polyol or polymer polyol having a molecular weight of 400 to 5000, a functional number of 2 to 8, and a hydroxyl value of 14 to 1200 mgKOH / g is preferred. On the other hand, as the polyol for flexible urethane foam, polyether polyols and polymer polyols having a molecular weight of 1,000 to 10,000, a functional number of 2 to 4 and a hydroxyl value of 10 to 300 mgKOH / g are preferred.

[0039] As the polyisocyanate, an aliphatic or aromatic polyisocyanate having two or more isocyanate groups, a mixture thereof, and a modified polyisocyanate obtained by modifying them can be used. As the aliphatic polyisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexamethane diisocyanate, etc. can be mentioned, and as the aromatic polyisocyanate, toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), naphthalene diisocyanate, xylylene diisocyanate, polymeric MDI (crude MDI), etc. can be mentioned. In addition, prepolymers can also be used.

[0040] The isocyanate index (INDEX) is preferably 80 to 120 or more, and more preferably 85 to 120. The isocyanate index is a value obtained by dividing the number of moles of isocyanate groups in an isocyanate by the total number of moles of active hydrogen groups such as hydroxyl groups in a polyol, and multiplying the result by 100, and is calculated by [(parts by weight of polyisocyanate / NCO equivalent of polyisocyanate) / (parts by weight of active hydrogen component / active hydrogen equivalent)×100].

[0041] As the blowing agent, water, alternative fluorocarbons, or hydrocarbons such as pentane can be used alone or in combination. In the case of water, carbon dioxide gas is generated during the reaction of polyol with isocyanate, and the carbon dioxide gas causes foaming. The amount of water used as the blowing agent is preferably 2 to 5 parts by weight per 100 parts by weight of polyol.

[0042] As the catalyst, a known urethane catalyst can be used in combination. For example, amine catalysts such as triethylamine, triethylenediamine, diethanolamine, dimethylaminomorpholine, N-ethylmorpholine, and tetramethylguanidine, tin catalysts such as stannous octoate and dibutyltin dilaurate, and metal catalysts such as phenylmercury propionate and lead octenate (also called organometallic catalysts), may be used alone or in combination of the amine catalyst and the metal catalyst. The amount of the catalyst is preferably 0.5 to 3 parts by weight based on 100 parts by weight of the polyol.

[0043] In addition, foam stabilizers, flame retardants, colorants, etc. may be appropriately blended into the urethane foam raw material.

[0044] When the front portion 13 is a semi-rigid or rigid urethane foam and the rear portion 15 is a flexible urethane foam, mold foaming is preferably used to manufacture the vehicle seat base material 11. Mold foaming is a foam molding method in which urethane foam raw material is injected into a mold and foamed within the mold, and wire frames, nonwoven fabrics, etc. can be easily insert molded. The method for manufacturing the vehicle seat base material 11 by mold foaming is described below.

[0045] The mold 50 shown in FIG. 2 is composed of a lower mold 51 and an upper mold 53 that covers the lower mold 51. The inner surface of the lower mold 51 has a mold surface 55 for molding the vehicle seat base material 11, which is configured to have the same shape as the upper surface of the vehicle seat base material 11. The mold surface 55 of the lower mold 51 is divided into a mold surface 55a for molding a front portion and a mold surface 55b for molding a rear portion by a partition plate 56 that stands upright from the mold surface 55. The position of the partition plate 56 coincides with the boundary position 17 (position of the groove 16) between the front portion 13 and the rear portion 15 of the vehicle seat base material 11. The partition plate 55 is provided so that a gap is generated between the upper end of the partition plate 56 and the mold surface 54 of the upper mold 53 when the lower mold 51 is covered with the upper mold 53.

[0046] Semi-rigid or rigid urethane foam raw material 131 is extruded onto the front portion molding surface 55a of the lower mold 51, while soft urethane foam raw material 151 is extruded onto the rear portion molding surface 55b, and the upper mold 53 is placed over the material to allow the semi-rigid or rigid urethane foam raw material 131 and the soft urethane foam raw material 151 to foam.

[0047] The semi-rigid or rigid urethane foam raw material 131 ejected onto the front portion molding mold surface 55a of the lower mold 51 foams and fills the space between the front portion molding mold surface 55a of the lower mold 51 and the mold surface 54 of the upper mold 53, while the soft urethane foam raw material 151 ejected onto the rear portion molding mold surface 55b of the lower mold 51 foams and fills the space between the rear portion molding mold surface 55b of the lower mold 51 and the mold surface 54 of the upper mold 53, so that the foamed semi-rigid or rigid urethane foam raw material 131 and the foamed soft urethane foam raw material 151 come into contact with each other in the gap between the upper end of the partition plate 56 and the mold surface 54 of the upper mold 53.

[0048] Thereafter, the semi-rigid or rigid urethane foam raw material 131 and the flexible urethane foam raw material 151 are cured, whereby the front portion 13 of the vehicle seat base material 11 is formed between the front portion molding mold surface 55a of the lower mold 51 and the mold surface 54 of the upper mold 53, while the rear portion 15 of the vehicle seat base material 11 is formed between the rear portion molding mold surface 55b of the lower mold 51 and the mold surface 54 of the upper mold 53, and the formed front portion 13 and rear portion 15 are bonded together in the gap between the upper end of the partition plate 56 and the mold surface 54 of the upper mold 53, thereby forming the vehicle seat base material 11. Thereafter, the mold 50 is opened, and the vehicle seat base material 11 is taken out.

[0049] On the other hand, when the front portion 13 is made of foamed polypropylene and the rear portion 15 is made of soft urethane foam, the vehicle seat base material 11 is manufactured as follows. Foamed polypropylene is formed in advance as the front portion 13 by the bead method in-mold foaming molding method, and the front portion 13 is set in a mold, and soft urethane foam raw material is injected to foam and form the rear portion 15, which is integrated with the front portion 13. At this time, the front portion 13 made of foamed polypropylene is treated with a primer to improve adhesion with the soft urethane foam of the rear portion 15.

[0050] The cushioning material 21 laminated on the vehicle seat base material 11 is preferably made of urethane foam. The urethane foam is preferably soft urethane foam. Soft urethane foam has good elasticity, and therefore can improve the cushioning properties of the vehicle seat 10.

[0051] The urethane foam constituting the cushioning material 21 has a density (in accordance with JIS K 7222) of 35 to 80 kg / m 3 By setting the density within this range, the overall lightweight property of the laminate for the vehicle seat can be improved. The cushion material 21 has a lower hardness than the resin foam of the rear portion 15 of the vehicle seat base material 11 .

[0052] The cushion material 21 may be foam-molded separately from the vehicle seat base material 11 and then laminated and adhered to the vehicle seat base material 11, or may be foam-molded integrally with the vehicle seat base material 11 by mold foaming. When foam-molding the cushion material 21 integrally with the vehicle seat base material 11 by mold foaming, the vehicle seat base material 11 previously molded is set in a mold, and urethane foam raw material (soft urethane foam raw material in this case) is injected into the mold to be foamed integrally with the vehicle seat base material 11. At that time, the cushion material 21 can be adhered to the vehicle seat base material 11 by the adhesiveness of the urethane foam raw material (soft urethane foam raw material), and the molding process of the cushion material 21 and the adhesion process can be combined. Furthermore, when the resin foam constituting the front portion 13 of the vehicle seat base material 11 is a semi-rigid urethane foam or a rigid urethane foam, the soft urethane foam constituting the cushion material 21 and the semi-rigid urethane foam or the rigid urethane foam constituting the vehicle seat base material 11 are both made of urethane foam, so that they have good adhesion to each other and there is no risk of peeling off after bonding.

[0053] The vehicle seat 10 is attached to the vehicle with its surface covered with a covering material (not shown) made of fabric or the like. EXAMPLES

[0054] 3 shows the physical properties of the material (foam) constituting the vehicle seat base material for the Comparative Example and Examples 1 to 3. For the Comparative Example and Examples 1 to 3, the density, 2% compression hardness, 5% compression hardness, 10% compression hardness, Asker C hardness, and Asker F hardness were measured for test samples of the front and rear parts of the vehicle seat base material.

[0055] The density was measured in accordance with JIS K 7222. The compression hardness was measured by compressing a test sample (100 mmt x 400 mm x 400 mm) with a pressure plate (diameter 100 mm) without pre-compression at a compression speed of 50 mm / min until the load reached 1000 N, and then releasing the compression by the pressure plate at a speed of 50 mm / min to obtain a load-deflection curve. The load at 2% compression was recorded as the 2% compression hardness, the load at 5% compression was recorded as the 5% compression hardness, and the load at 10% compression was recorded as the 10% compression hardness. The Asker C hardness was measured by using an Asker C hardness tester (pressure surface height: 2.54 mm, diameter 5.08 mm) to measure the hardness by contacting the pressure surface of the test sample. The Asker F hardness was measured by using an Asker F hardness tester (pressure surface height: 2.54 mm, diameter 25.2 mm) to measure the hardness by contacting the pressure surface of the test sample.

[0056] In the comparative example, the front and rear parts of the vehicle seat base material are made of a single foamed polypropylene. Product name: EPP, foamed polypropylene made by JPS was used. The foamed polypropylene in the comparative example has a density of 33 kg / m 3 The 2% compression hardness is 1500N, the 5% compression hardness is 2500N, the 10% compression hardness is 3000N, the Asker C hardness is 55 degrees, and the Asker F hardness is 98 degrees. The compression hardness and Asker C hardness are high (hard), so the feel when initially sitting down and the cushioning while sitting down are poor, and there is a risk of bottoming out.

[0057] Example 1 is an example in which the front portion of the vehicle seat base material is made of semi-rigid urethane foam and the rear portion is made of soft urethane foam. The semi-rigid urethane foam was prepared by molding a sample having a plate shape of 100 mmt×400 mm×400 mm by molding the semi-rigid urethane foam raw material consisting of the following ingredients into a sample by mold foaming. Polyol 1: 20 parts by weight of a polyol consisting of polyether polyol, molecular weight: 1000, functionality: 3, and hydroxyl value: 168 mg KOH / g Polyol 2: 80 parts by weight of a polyol consisting of polymer polyol, solids (polymer content) 33%, molecular weight 5000, and hydroxyl value 24 mgKOH / g Polyol 3: 1.2 parts by weight of polyol consisting of glycerin, molecular weight: 92, functionality: 3, hydroxyl value: 1826 mg KOH / g Foaming agent: Water 4 parts by weight Amine catalyst: Tosoh ETS... 0.04 parts by weight Amine catalyst: Tosoh L33PG 1.1 parts by weight Foam stabilizer: Silicone-based, MOMENTIVE, L3184J... 0.2 parts by weight Isocyanate: Diphenylmethane diisocyanate, Sumika Covestro urethane, Sumidur 44V20L, NCO%: 31.8% Isocyanate index: 100

[0058] The soft urethane foam was prepared by molding a sample having a plate shape of 100 mmt×400 mm×400 mm by foaming in a mold from the soft urethane foam raw material consisting of the following ingredients. Polyol 1: 45 parts by weight of a polyol consisting of polyether polyol, molecular weight: 5000, functionality: 3, and hydroxyl value: 33.6 mg KOH / g Polyol 2: 25 parts by weight of a polyether polyol having a molecular weight of 7000, a functionality of 3, and a hydroxyl value of 24 mgKOH / g Polyol 3: 30 parts by weight of a polyol consisting of polymer polyol, solids (polymer content) 33%, molecular weight 5000, and hydroxyl value 24 mgKOH / g Polyol 4: 1.1 parts by weight of polyol consisting of glycerin, molecular weight: 92, functionality: 3, hydroxyl value: 1826 mg KOH / g Foaming agent: Water 3.5 parts by weight Amine catalyst: Tosoh ETS... 0.05 parts by weight Amine catalyst: Tosoh Corporation, L33PG... 0.5 parts by weight Amine catalyst: Mitsui Chemicals, DEA80... 1 part by weight Foam stabilizer: Silicone-based, MOMENTIVE, L3184J... 0.5 parts by weight Isocyanate: Toluene diisocyanate, Sumika Covestro urethane, Desmodur T80, NCO%: 48.3% Isocyanate index: 95

[0059] In Example 1, the semi-rigid urethane foam constituting the front portion has a density of 40 kg / m 3 The 2% compression hardness is 354N, the 5% compression hardness is 576N, the 10% compression hardness is 648N, the Asker C hardness is 33 degrees, and the Asker F hardness is 98 degrees, which provides a good feel when initially sitting down and good cushioning. The soft urethane foam that makes up the rear part has a density of 55kg / m 3, 2% compression hardness is 29N, difference from the front portion is 325N, 5% compression hardness is 54N, difference from the front portion is 522N, 10% compression hardness is 73N, difference from the front portion is 575N, Asker C hardness is 4 degrees, difference from the front portion is 29 degrees, Asker F hardness is 70 degrees, difference from the front portion is 28 degrees.Since the 2% compression hardness, 5% compression hardness and Asker C hardness are low, the feel at the beginning of sitting is good, and since the 10% compression hardness is lower than the foamed polypropylene of the comparative example, cushioning while sitting is good and it is possible to prevent a feeling of bottoming out in the buttocks and the surrounding areas.

[0060] Furthermore, in Example 1, the 10% compression hardness and Asker C hardness are higher (harder) in the front portion than in the rear portion, and the 10% compression hardness of the rear portion is soft at 73 N, so that when seated, the rear portion sinks more than the front portion, thereby preventing the occurrence of the submarine phenomenon.

[0061] In the second embodiment, the front portion of the vehicle seat base material is made of a hard urethane foam, and the rear portion is made of a soft urethane foam similar to that in the first embodiment. The rigid urethane foam was prepared by molding a sample having a plate shape of 100 mmt×400 mm×400 mm by molding the rigid urethane foam raw material consisting of the following ingredients into a mold. Polyol 1: 95 parts by weight of a polyol consisting of polyether polyol, molecular weight: 400, functionality: 3, and hydroxyl value: 420 mg KOH / g Polyol 2: 5 parts by weight of polyol consisting of glycerin, molecular weight: 92, functionality: 3, hydroxyl value: 1824 mg KOH / g Amine catalyst: Tosoh L33PG... 1.5 parts by weight Foam stabilizer: Tosoh Corporation, L3184J... 0.5 parts by weight Isocyanate: Sumika Covestro urethane, Sumidur 44V20L, NCO%: 31.5% Isocyanate index: 105 The soft urethane foam was prepared by molding a sample having a plate shape of 100 mmt×400 mm×400 mm by molding the same soft urethane foam raw material as in Example 1 using mold foaming.

[0062] In Example 2, the rigid urethane foam constituting the front portion has a density of 60 kg / m 3 , 2% compression hardness is 2500N, 5% compression hardness is 5500N, 10% compression hardness is 9000N, Asker C hardness is 75 degrees, and Asker F hardness is 100 degrees. The soft urethane foam constituting the rear portion has the same physical properties as in Example 1, and has a density of 55 kg / m 3 , 2% compression hardness is 29N, difference from the front portion is 2471N, 5% compression hardness is 54N, difference from the front portion is 5446N, 10% compression hardness is 73N, difference from the front portion is 8927N, Asker C hardness is 4 degrees, difference from the front portion is 71 degrees, Asker F hardness is 70 degrees, difference from the front portion is 30 degrees.Since the 2% compression hardness, 5% compression hardness and Asker C hardness of the rear portion are low, the feel at the beginning of sitting is good, and since the 10% compression hardness is lower than the foamed polypropylene of the comparative example, cushioning while sitting is good and a feeling of bottoming out in the buttocks and surrounding areas can be prevented.

[0063] Furthermore, in Example 2, the 10% compression hardness and Asker C hardness are higher (harder) in the front portion than in the rear portion, and the 10% compression hardness of the rear portion is soft at 73 N, so that when seated, the rear portion sinks more than the front portion, thereby preventing the occurrence of the submarine phenomenon.

[0064] In the third embodiment, the front portion of the vehicle seat base material is made of foamed polypropylene, and the rear portion is made of the same soft urethane foam as in the first and second embodiments. The foamed polypropylene in the front portion was the same as that in the comparative example, and was made of foamed polypropylene manufactured by JPS, product name: EPP, cut into a plate shape of 100 mmt×400 mm×400 mm. The foamed polypropylene that makes up the front part has a density of 33 kg / m 3, 2% compression hardness is 1500N, 5% compression hardness is 2500N, 10% compression hardness is 3000N, Asker C hardness is 55 degrees, and Asker F hardness is 98 degrees. The soft urethane foam constituting the rear portion has the same physical properties as in Examples 1 and 2, and has a density of 55 kg / m 3 , 2% compression hardness is 29N, difference from the front portion is 1471N, 5% compression hardness is 54N, difference from the front portion is 2446N, 10% compression hardness is 73N, difference from the front portion is 2927N, Asker C hardness is 4 degrees, difference from the front portion is 51 degrees, Asker F hardness is 70 degrees, difference from the front portion is 28 degrees.Since the 2% compression hardness, 5% compression hardness and Asker C hardness of the rear portion are low, the feel at the beginning of sitting is good, and since the 10% compression hardness is lower than the foamed polypropylene of the comparative example, cushioning while sitting is good and it is possible to prevent a feeling of bottoming out in the buttocks and the surrounding areas.

[0065] Next, for the comparative examples and examples of the rear portion of the vehicle seat, the table in FIG. 4 shows the material, thickness, density, 2% compression hardness, 5% compression hardness, 10% compression hardness of the cushion material and the rear portion of the vehicle seat base material, and the load measurement values ​​and evaluations at 10 mm compression (corresponding to the initial state of sitting), 20 mm compression (corresponding to when sitting), and 25 mm compression (corresponding to when bottoming out) of the laminated state of the cushion material and the rear portion of the vehicle seat base material (rear portion of the vehicle seat).

[0066] The density, 2% compression hardness, 5% compression hardness, 10% compression hardness, and Asker C hardness were measured in the same manner as the respective measurement methods described above. The loads applied to the laminate in which the cushioning material is laminated on the rear portion of the vehicle seat base material at 10mm, 20mm, and 25mm compression were measured by cutting a test sample to 60mmt x 400mm x 400mm, compressing it at a compression speed of 50mm / min without pre-compression until the load reached 1000N, and then releasing the compression at a speed of 50mm / min to obtain a load-deflection curve, from which the loads at 5% compression and 10% compression were obtained. The pressure plate used was an ISO6549 iron grinding plate (300mm x 250mm). When the measured value when compressed 10 mm was less than 220 N, it was rated as "good", and when it was 220 or more, it was rated as "poor". When the measured value when compressed 20 mm was between 320 and 380 N, it was rated as "good", and when it was less than 320 or 380 or more, it was rated as "poor". If the measured value when compressed 25 mm was less than 520 N, it was rated as "good", and if it was 520 or more, it was rated as "poor".

[0067] The comparative example is 40mm thick x 400mm x 400mm thick, with a density of 40kg / m 3 The thickness is 100mm x 400mm x 400mm, the hardness is 2% compression hardness 13N, 5% compression hardness 23N, 10% compression hardness 32N, and Asker C hardness 1 soft urethane foam (cushion material) and the thickness is 20mm x 400mm x 400mm, density is 33kg / m 3 It is made of a laminate (non-adhesive) with foamed polypropylene (rear part of vehicle seat base material) with a thickness of 100mm x 400mm x 400mm, a hardness of 2% compression hardness of 1500N, 5% compression hardness of 2500N, 10% compression hardness of 3000N, and an Asker C hardness of 55 degrees. The laminate of the comparative example had a load of 203 N when compressed by 10 mm (when initially sitting) and was rated as "good", a load of 350 N when compressed by 20 mm (when sitting) and was rated as "good", and a load of 537 N when compressed by 25 mm (when bottoming out) and was rated as "poor". The feel was good when initially sitting, but bottoming out occurred and the cushioning was poor.

[0068] The soft urethane foam (cushion material) of the comparative example was formed by mold foaming using a soft urethane foam raw material having the following composition. Polyol 1: 30 parts by weight of a polyol consisting of polyether polyol, molecular weight: 5000, functionality: 3, and hydroxyl value: 33.6 mg KOH / g Polyol 2: 50 parts by weight of a polyol consisting of polyether polyol, molecular weight: 7000, functionality: 3, and hydroxyl value: 24 mg KOH / g Polyol 3: 20 parts by weight of a polyol consisting of polymer polyol, solids (polymer content) 33%, molecular weight 5000, and hydroxyl value 24 mgKOH / g Polyol 4: 1.2 parts by weight of polyol consisting of glycerin, molecular weight: 92, functionality: 3, and hydroxyl value: 1826 mg KOH / g Foaming agent: Water 3.5 parts by weight Amine catalyst: Tosoh ETS... 0.05 parts by weight Amine catalyst: Tosoh Corporation, L33PG... 0.5 parts by weight Amine catalyst: DEA80 manufactured by Mitsui Chemicals, 1.2 parts by weight Foam stabilizer: Silicone-based, manufactured by MOMENTIVE, L3184J... 0.4 parts by weight Isocyanate: Sumika Covestro urethane, Desmodur T80. NCO%: 48.3% Isocyanate index: 95 The foamed polypropylene (rear portion of the vehicle seat base material) was formed by cutting out foamed polypropylene (product name: EPP, manufactured by JPS).

[0069] The example is 40mm thick x 400mm x 400mm thick, with a density of 40kg / m 3 The thickness is 100mm x 400mm x 400mm, the hardness is 2% compression hardness 13N, 5% compression hardness 23N, 10% hardness 32N, and Asker C hardness 1 soft urethane foam (cushion material) and the thickness is 20mm x 400mm x 400mm, density is 55kg / m 3 It is made of a laminate (non-adhesive) with soft urethane foam (rear part of vehicle seat base material) with a thickness of 100mm x 400mm x 400mm and hardness of 2% compression hardness 29N, 5% compression hardness 54N, 10% hardness 73N, and Asker C hardness 4.

[0070] The laminate of the embodiment had a load of 191 N when compressed by 10 mm (when initially sitting) and was rated as "good", a load of 350 N when compressed by 20 mm (when sitting) and was rated as "good", and a load of 447 N when compressed by 25 mm (when bottoming out) and was rated as "good". The feel was good when initially sitting, there was no bottoming out, and the cushioning properties were good.

[0071] The soft urethane foam of the cushioning material in the examples was formed by mold foaming using a soft urethane foam raw material having the same composition as in the comparative examples. The flexible urethane foam in the rear portion of the vehicle seat base material in the examples was formed by mold foaming using a flexible urethane foam raw material having the following composition. Polyol 1: 45 parts by weight of a polyol consisting of polyether polyol, molecular weight: 5000, functionality: 3, and hydroxyl value: 33.6 mg KOH / g Polyol 2: 25 parts by weight of a polyol consisting of polyether polyol, molecular weight: 7000, functionality: 3, and hydroxyl value: 24 mg KOH / g Polyol 3: 30 parts by weight of a polyol consisting of a polymer polyol, molecular weight: 5000, hydroxyl value: 24 mgKOH / g Polyol 4: 1.1 parts by weight of polyol consisting of glycerin, molecular weight: 92, functionality: 3, and hydroxyl value: 1826 mg KOH / g Foaming agent: Water 3.5 parts by weight Amine catalyst: Tosoh ETS... 0.05 parts by weight Amine catalyst: Tosoh Corporation, L33PG... 0.5 parts by weight Amine catalyst: Mitsui Chemicals, DEA80... 1 part by weight Foam stabilizer: Silicone-based, MOMENTIVE, L3184J... 0.5 parts by weight Isocyanate: Toluene diisocyanate, Sumika Covestro urethane, Desmodur T80, NCO%: 48.3% Isocyanate index: 95 The soft urethane foam of the cushioning material and the soft urethane foam of the rear portion of the vehicle seat base material were each foam-molded and then laminated.

[0072] Thus, the vehicle seat base material and vehicle seat of the present invention provide a comfortable sitting experience for the buttocks and can suppress the submarine phenomenon when an impact occurs due to a vehicle collision, sudden braking, or the like. [Explanation of symbols]

[0073] 10 Vehicle seats 11 Vehicle seat base material 13 Front part (back of the knee and the area that receives pressure) 15 Rear part (buttocks and surrounding areas that are subject to pressure) 21 Cushioning material 50 Mold 51 Lower mold 53 Upper mold 54 Upper die surface 55 Lower die surface 55a Mold surface for front part molding 55b Mold surface for molding the rear part 56 Partition 131 Semi-rigid urethane foam raw materials 151 Soft urethane foam raw materials

Claims

1. In a vehicle seat base material on which a cushioning material is laminated, The seat cushion has a front portion that is pressed by the back of the knees of the seated person and a rear portion that is pressed by the buttocks of the seated person, the front portion and the rear portion are made of a resin foam, the resin foam of the front portion is harder than the resin foam of the rear portion; A vehicle seat base material, characterized in that the resin foam in the front portion is semi-rigid urethane foam, rigid urethane foam or foamed polypropylene, and the resin foam in the rear portion is soft urethane foam.

2. A vehicle seat base material on which a cushioning material is laminated, The seat cushion has a front portion that is pressed by the back of the knees of the seated person and a rear portion that is pressed by the buttocks of the seated person, the front portion and the rear portion are made of a resin foam, the resin foam of the front portion is harder than the resin foam of the rear portion; A vehicle seat base material, characterized in that a groove is formed on a seat surface side of a boundary portion between the front portion and the rear portion.

3. A vehicle seat base material on which a cushioning material is laminated, The seat cushion has a front portion that is pressed by the back of the knees of the seated person and a rear portion that is pressed by the buttocks of the seated person, the front portion and the rear portion are made of a resin foam, the resin foam of the front portion is harder than the resin foam of the rear portion; The resin foam of the front portion satisfies all of the following: 1) 2% compression hardness of 354 to 2500 N, 2) 5% compression hardness of 576 to 5500 N, 3) 10% compression hardness of 648 to 9000 N, and 4) Asker C hardness of 33 to 75 degrees; The difference in hardness between the resin foam of the front portion and the resin foam of the rear portion satisfies all of the following: 1) a difference in 2% compression hardness of 325 to 2471 N, 2) a difference in 5% compression hardness of 522 to 5446 N, 3) a difference in 10% compression hardness of 575 to 8927 N, and 4) a difference in Asker C hardness of 29 to 71 degrees. The resin foam in the rear portion satisfies all of the following requirements: 1) a 2% compression hardness of 20 N or more and less than 100 N, 2) a 5% compression hardness of 40 N or more and less than 200 N, 3) a 10% compression hardness of 60 N or more and less than 300 N, and 4) an Asker C hardness of 2 degrees or more and less than 20 degrees.

4. A vehicle seat base material on which a cushioning material is laminated, The seat cushion has a front portion that is pressed by the back of the knees of the seated person and a rear portion that is pressed by the buttocks of the seated person, the front portion and the rear portion are made of a resin foam, the resin foam of the front portion is harder than the resin foam of the rear portion; The vehicle seat base material is characterized in that the density of the resin foam constituting the rear portion is 55 to 70 kg / m 3 .

5. In a vehicle seat in which a cushioning material is laminated on a vehicle seat base material, The vehicle seat base material is the vehicle seat base material according to any one of claims 1 to 4, The vehicle seat, wherein the cushioning material is made of urethane foam.

6. A vehicle seat having a cushioning material laminated on a vehicle seat base material, The vehicle seat base material has a front portion that is pressed by the back of the knees of a seated person and a rear portion that is pressed by the buttocks of the seated person, the front portion and the rear portion are made of a resin foam, the resin foam of the front portion is harder than the resin foam of the rear portion; The cushioning material is made of urethane foam, The vehicle seat, wherein the cushioning material covers a front side of the front portion and is thicker than the rear portion.

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