WO2002069765A1

WO2002069765A1 - Seat cushion pad

Info

Publication number: WO2002069765A1
Application number: PCT/JP2001/001698
Authority: WO
Inventors: Atsushi Kazuno; Masanobu Banno; Takanori Sugie; Katsuya Satoh; Kikuo Sekita
Original assignee: Toyo Tire & Rubber Co., Ltd.
Priority date: 2001-03-05
Filing date: 2001-03-05
Publication date: 2002-09-12
Also published as: JPWO2002069765A1; JP3644640B2

Abstract

A seat cushion pad suitable for vibrating vehicles, having a vibration transmission rate in the vicinity of 6 Hz kept at as high a damping property as conventionally experienced with a resonance magnification at 2-4 Hz lowered, and excellent in a fitting feeling when more than one person take seats at the same time. The seat cushion pad which is formed from a molded polyurethane foam, wherein the seating surface has a one-layer structure, a resonance magnification at 2-4 Hz measured by a forced vibration test conducted at an amplitude of ±2.5 mm under a load of a 50-kg grinding-shaped, pressurized iron sheet is up to 4, an impact resilience modulus of a core layer is 50-70 %, and the polyurethane foam material uses, as polyol components, 60-80 pts.wt. of polyether polyol having a hydroxyl value of 20-40 mg KOH/g and 40-20 pts.wt. of polymer polyol having a hydroxyl value of 15-30 mg KOH/g, a silicon foam shaping agent, a foaming agent, and, as a polyisocyanate compound, diphenyl-methane-diisocyanate.

Description

Description Name of Invention

Seat Cushion ,. Good

[Technical field]

The present invention relates to a seat cushion pad made of a polyurethane foam. In particular, the seat cushion pad of the present invention is suitable for a seat cushion pad for a vehicle, particularly an automobile, which vibrates when used.

[Background technology]

In automobiles, in order to reduce the transmission of engine vibrations and vibrations caused by vehicle travel, and to ensure the comfort of passengers and occupants, suspension systems that absorb vibrations due to uneven road surfaces and engine vibrations are absorbed. Various vibration transmission preventing means such as an engine mount are used. In addition, a good feeling when sitting is required because the seat is made of a highly cushioning flexible polyurethane foam. There are various types of automobiles such as trucks and passenger cars, and passenger cars also have various grades. In addition, 伝達 ^! Dogs, applications, and selling prices are taken into consideration, and vibration transmission prevention means are also selected and used. Such vibration transmission preventing means cannot completely prevent vibration transmission at all frequencies, and there are frequencies disadvantageous to vibration transmission prevention depending on the type. For this reason, various characteristics are required for the flexible polyurethane foam for the seat cushion, including the characteristic of preventing vibration transmission, depending on the application.

Conventionally, in order to improve the riding comfort of automobile seat cushions ¾t, the vibration frequency range that people feel uncomfortable with regard to the JASOB-407 prescribed vibration transmissibility characteristics

It is said that it is effective to greatly attenuate (4 to 10 Hz: a vibration transmissibility of 6 Hz is usually adopted as the evaluation value). In particular, vibration around 6 Hz is said to be the frequency that causes car sickness.Therefore, even in a vehicle cushion pad made of urethane foam, the vibration transmission rate must be kept low. ^ ¹ has been developed. However, conventional seat cushions, with low vibration transmission at 6 Hz. The head has a large resonance magnification (resonance peak) appearing at 2 to 4 Hz in the vibration transmissibility characteristics, so that when an occupant is seated on an automobile seat cushion and runs, the body is subject to vibration due to body vibration. The sense of stability was lost, and the sensation of swinging the body up and down (so-called chilling feeling) could not be sufficiently prevented.

Under these circumstances, seat cushion pads for vehicles, including automobiles, not only reduce the vibration transmissibility around 6 Hz but also reduce driving sickness and reduce fatigue during driving. It is also necessary to improve safety (improvement of stability when sitting on the seat), and it is considered preferable to show a low vibration transmissibility even in a wider frequency range.

However, in general, in terms of vibration engineering, the vibration transmissivity characteristic curve (vertical axis: vibration transmissivity, horizontal axis: frequency) is obtained by lowering the resonance magnification at 2 to 4 Hz of the vibration transmissibility characteristic. However, the vibration transmissibility at a relatively high frequency (for example, 6 Hz) related to the cushioning property increases, and the vibration transmissibility characteristic curve becomes a broad curve as a whole. That is, in the vibration transmissibility characteristic curve, a decrease in the vibration transmissivity and a decrease in the resonance magnification had a trade-off relationship.

Therefore, an object of the present invention is to provide a high attenuation property that can reduce the resonance magnification at 2 to 4 Hz and reduce the vibration transmissibility around 6 Hz to the same level as or less than the conventional one. Another object of the present invention is to provide a seat cushion pad having an excellent fit when seated at the same time.

[Disclosure of the invention]

The present invention relates to a sheet cushion pad comprising a polyurethane foam having a skin layer and a core layer formed by injecting a polyurethane foam material into a mold,

The seat has a one-layer structure,

The resonance magnification at 2 to 4 Hz was 4 or less and the rebound resilience of the core layer was 5 0 to 70%, The polyurethane foam raw material has a hydroxyl value of 20 to 40 mg KOH / g as a polyol component, 60 to 80 parts by weight of a polyether polyol having an ethylene oxide unit at the end, and 7 an acid value of 1 5 to 30 mg K0H / g of polymer polyol 40 to 20 parts by weight, a silicone foam stabilizer, a foaming agent, and diphenylmethane diisocyanate as a polyisocyanate conjugate It is characterized by being used.

The seat cushion pad with the above configuration has a low resonance magnification at 2 to 4 Hz, and the vibration transmissibility at around 6 Hz is equal to or less than the conventional one, has high damping properties, and sits at the same time. Seat cushioning, with a good fit when you do it. The polyurethane foam raw material is a copolymer of ethylene oxide and propylene oxide having a molecular weight of 100 to 500, and the copolymerization ratio of ethylene oxide is 50% by weight. ^_0/0 or more in a polymer as a foam breaking agent, it is preferred for the polyol component 1 0 0 part by weight 0. 5 are those containing 5 parts by weight. By using the above-mentioned foam breaking agent, it is possible to reduce the resonance magnification while suppressing the resonance frequency from becoming 4 Hz or more. A compound having an ethylene oxide content of less than 50% by weight has a small foam breaking effect, and a resonance magnification while suppressing the resonance frequency from becoming 4 Hz or more even when the molecular weight is out of the above range. The effect of lowering is not obtained. If the added amount of the above-mentioned foaming agent is less than 0.5 parts by weight, the foaming effect cannot be sufficiently obtained, so that the ratio of insect-bubble bubbles in the foam increases, and the seat cushion pad is formed during molding. Cracks may appear on the screen. If the amount of the foaming agent exceeds 5 parts by weight, the foaming effect becomes too strong and the resonance magnification becomes high.

The foaming agent may have a polymerization ratio of ethylene oxide of '100%. Further, the addition amount of the foaming agent is more preferably 1 to 4 parts by weight.

The silicone foam stabilizer preferably has an average free foam height of not less than 225 mm.

The average value of the free foam height, which indicates the characteristics of the silicone foam stabilizer used, is the foam height measured using the model formulation shown in the following (Table 1). The average value of the free foaming foam height is obtained by evaluating the properties of the foam stabilizer using a model compound. The height of the free-foamed foam was determined by weighing the raw materials shown in Table 1 above so that the total weight would be 147.3 ± 0.5 g, the bottom diameter being 105 mm, and the opening diameter being 1 mm. It is determined by measuring the height to the top of the foam when foamed in a truncated cone with a height of 4 O mm and a height of 195 mm.

(table 1 )

In the measurement of the height of the free-foamed foam, the polyol component containing the polyol conjugate in the upper column of (Table 1) was uniformly premixed, and the polyol component and the isocyanate component were separately mixed. Measure the height of the foam formed by adjusting the temperature to 25 ° C, mixing uniformly, and foaming under the specified conditions. Mixing is performed using a well-known stirrer capable of uniformly stirring the polyol component and the isocyanate component in a short time of about 5 seconds. By using such a silicone foam stabilizer, the resonance magnification at 24 Hz is low, and It is possible to more reliably and stably obtain a high-damping seat or solution pad having a vibration transmissibility near 6 Hz which is equal to or less than the conventional one. Silicon uniform Foaming agents that have an average free foam height of at least 25 mm can be used, even if a mixture of two or more components is used.

The silicone foam stabilizer is represented by polydimethylsiloxane or (chemical formula 1), in which the equivalent ratio m / n of the ethylene copolymer unit m and the propylene oxide unit n in the copolymerized polyether is 0. It is preferably a compound having a ratio of 4 / 0.6 to 0.05 / 0.95.

(Chemical formula 1)

CH ₃

(In (Chemical formula 1), X is an organic residue having 1 to 4 carbon atoms, R is an alkyl group or an acyl group, X is 80 to 250, and y is 0 to 50. ')

[Brief description of drawings]

Figure 1 is a cross-sectional view of an example of a seat cushion pad with a seat thickness of 65 mm. Figure 2 is a diagram showing the method of measuring the free foam height.

Fig. 3 is a graph showing the measurement results of the vibration transmissibility of the seat cushion pad at a frequency of 10 Hz or less.

[Best Mode for Carrying Out the Invention]

The polyol compound used in the flexible polyurethane foam of the present invention may be any type as long as the resonance frequency, resonance magnification and elastic modulus of the core layer of the obtained sheet cushion pad are within predetermined ranges. Although there is no particular limitation, the polyol compound of the present invention is preferably a combination of polyoxyalkylene glycol and polymer polyol. As the polyoxyalkylene glycol, a so-called polyether polyol obtained by adding an alkylene oxide to a polyfunctional alcohol compound as an initiator is usually used.

Examples of polyfunctional alcohol compounds include ethylene glycol, propylene glycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol, sucrose, triethanolamine, and diethanolamine. The added compound can be exemplified. Alkylene oxides that are addition-polymerized to polyfunctional alcohol compounds include those having 2 or more carbon atoms, such as ethylene oxide, 1,2-propylene oxide, 2-butylene oxide, and 3-butylene oxide. And styrene oxide. Among these alkylene oxides, those in which propylene oxide and / or butylene oxide are used in combination with ethylene oxide are low in cost, and the characteristics of the obtained seat cushion pad are good. And so on. In particular, those containing ethylene oxide ring-opened ethylene oxide units in an addition ratio of 3 to 50% by weight, more preferably 3 to 25% by weight are preferable.

The boroxyalkylene glycol may be either a random polymer or a block polymer of the above-described alkylene oxide, but a polymer containing a oxyethylene unit at the terminal is preferable because of good reactivity with an isocyanate group. 1 quaternizing rate of end (terminal E Ji Ren O key side unit rate) is preferably one containing poly O carboxymethyl 3 wt ^_0/0 or more O Kishiarukiren alkylene glycol units, those containing 5 wt ^0/6 or more Gayori It is preferably, particularly preferably, 10 to 20% by weight.

The molecular weight between crosslinks (molecular weight per hydroxyl group) of such a polyoxyalkylene polyol is preferably about 1000 to 400, and particularly, the molecular weight between crosslinks is 150 to 280. The use of 0 is preferred.

In the present invention, a polymer polyol obtained by dispersing polymer particles in the form of fine particles in a polyol compound is used.

Examples of the above polymer particles include homopolymers of vinyl monomers such as acrylonitrile, styrene, alkyl methacrylate, and alkyl acrylate. Or particles of an addition polymerization type polymer such as a copolymer or a condensation polymerization type polymer such as a polyester, a polyurea or a melamine resin. Among these, a homopolymer or copolymer of acrylonitrile and styrene is preferred. Particularly, a homopolymer of acrylonitrile is preferred. In addition, as the polymer particles, a system containing atarilonitrile polymer fine particles is preferable because the moldability of the sheet cushion pad is good.

The proportion of the polymer particles in the whole polyol component is preferably not more than 40% by weight, more preferably not more than 20% by weight, because if the ratio is too large, it causes economic disadvantage. In order to effectively improve the physical properties such as hardness and durability of the sheet cushion pad, it is preferable that the ratio of the polymer particles in the entire polyol component is 1% by weight or more, and more preferably 2% by weight or more. .

The method of introducing such polymer particles into the polyol compound is not particularly limited.For example, when the polymer particles are addition-polymerized polymers, the presence of a radical polymerization initiator in a polyol such as polyoxyalkylene polyol is considered. By polymerizing a butyl monomer such as styrene or acrylonitrile below, it can be stably dispersed in the polyol compound. Polymer polyols (POF) are commercially available from Mitsui Chemicals, Asahi Glass and the like, and can be suitably used.

It is preferable that both the above-mentioned polyester polyol and the polyalkylene polyol constituting the polymer polyol have a low terminal unsaturated group concentration.Specifically, the terminal unsaturated group concentration is me 0.1 meq Z g The following is preferred.

As described above, polyisocyanate compounds include diphenylmethane diisocyanate (MDI) (purified diphenylmethane diisocyanate (p-MDI), crude MDI (c-MDI), carbodiimide modified MDI or There is uretonimine metamorphic MDI.

In addition to diphenylmethane diisocyanate (MDI), seat cushions. Aromatic, alicyclic, and aliphatic polyisocyanate compounds having two or more isocyanate groups, which are generally used in the production of tablets, and various polyisocyanate compounds obtained by modifying these polyisocyanate compounds. The modified polyisocyanate compound thus obtained may be used for adjusting properties within a range that does not impair the object of the present invention. Specific examples of polyisocyanate compounds that can be used in combination with diphenylmethane diisocyanate (MDI) include toluene diisocyanate (TDI) and xylylene

Examples of the modified products include prepolymers of polyisocyanate compounds, modified isocyanates, modified urea, modified carbodiimides, and the like.

Water is used as the blowing agent, but it is also preferable to use another blowing agent together with water. HCFC-141b, HFC-134a, HFC_245fa, HFC-3.65mfc, etc., and halogenated hydrocarbons such as cyclopentane-n-pentane Examples include boiling point aliphatic or alicyclic hydrocarbons, liquefied carbon dioxide, and the like. To use them together, it is preferable to use liquefied carbon dioxide gas.

Blowing agent, the core density is added to a 50-65 kg / m ³ is, shea - balance with other properties such as naturally required 25% compression hardness as cushions pad good sheet This is preferable because a cushion pad can be obtained.

As the foam stabilizer, use a foam stabilizer having an average value of free foam foam height of not less than 225 mm evaluated by the foaming stock solution composition described in (Table 1). As such a silicone-based foam stabilizer, known foam stabilizers such as polydimethylsiloxane and derivatives thereof can be used without any limitation, and the compound represented by the above-mentioned formula (1) is preferable. As the silicone-based foam stabilizer, a commercially available product is preferably used. Specifically, SF2965, SF2962, SF2904, SF2908, SRX294A, (Toray Dow Corning Silicon) , L-5366, L-5 309 (manufactured by Nippon Rikiichi Co., Ltd.), B 8680 (Gold Schmitttone: h®) and the like are commercially available. Among them, SF2965, SF2962. L-5366, L-5309 are compounds represented by the above-mentioned (Chemical formula 1), and the m / n ratio and x, y belong to suitable ranges. This is illustrated as an example. In particular, it is effective to use a foam stabilizer having a surface tension lowering ability (difference between surface tension before and after addition to the polyol component) of about 1 (dyne / cm). The use of 2962, B 8680, L-5366, L-5309 is particularly preferred. However, it is also possible to adjust the surface tension and the surface tension lowering ability by using a plurality of foam stabilizers instead of a single foam stabilizer. Use with other foam stabilizers If you are, SF 2 9 6 5, SF 2 96 2, B 8 6 80, L- 5 3 66, L foam stabilizer selected from a 53 0 9 1 0 weight ZenSeiawa agent ⁰ / It is preferable to use ₀ or more.

In the present invention, it is preferable to use a foaming agent in addition to the above-mentioned silicone-based foam stabilizer. Molecular weight of copolymer of 1 000 to 50 0 0 of ethylene O key side and propylene Nokisaido, as the defoaming agent copolymerization ratio of ethylene O · The side of 50 wt. ^_0/0 or more polymers, the A compound produced by subjecting ethylene oxide or propylene oxide to ring-opening polymerization can be used for the polyfunctional alcohol compound used in the production of the prepared polyoxyalkylene polyol. As the polyfunctional alcohol compound to be used, water, ethylene glycol, 1,4-butanediol, glycerin, trimethylolpropane and the like are suitable. The foam breaking agent may be a block copolymer of ethylene oxide and propylene oxide, or may be a random copolymer. The use of a commercially available product is also preferable, and examples of suitable commercially available products include Pull Mouth Nick (manufactured by BASF), EP-505S (manufactured by Tanigaku) and the like.

Examples of urethanization catalysts include triethylenediamine (TEDA, Dab c0), bis (N, N-dimethylamino-2-ethyl) ether, N, N, Ν ', ·' -tetramethylhexamethylene diamine Amine-based catalysts such as benzene, bis (-dimethylaminoethyl) ether (TOYOCAT-II; manufactured by Tosoh), metal carboxylate such as potassium acetate and potassium octylate, and organic gold such as dibutyltin dilaurate. Genus compounds and the like. Among these, the use of an amine catalyst is preferred in that it is suitable for the production of a water-foamable polyurethane foam.

In the production of the seat cushion pad of the present invention, it is also a preferable embodiment to use a low-molecular-weight polyvalent active hydrogen compound as required, and the rigidity and the like of the seat cushion pad can be easily adjusted. Examples of such low molecular weight polyvalent active hydrogenated compounds include polyhydric alcohols such as ethylene glycol, propylene glycol, 1,4-butanediol, trimethylolpropane, and glycerin, and polyhydric alcohol pages thereof. Hydroxyl value obtained by polymerizing ethylene oxide / propylene oxide as an initiator and having a hydroxyl value of 300 to 100 mg OOH / g Examples are alkanolamines such as noethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine and the like. These compounds may be used alone or in combination of two or more. The use of commercially available products using these compounds is also suitable, for example, KL-110 (manufactured by Mitsui Chemicals), Hardmaster 1 (manufactured by Daiichi Kogyo Seiyaku), EL-980. (Made by Asahi Glass Co., Ltd.).

The amount of each component used in the polyurethane foam raw material containing the polyol mixture, the polyisocyanate component, the foaming agent, the catalyst, and the foam stabilizer is usually as follows. Needless to say, the amount of the core layer of the cushion pad can be appropriately changed in order to adjust the elastic modulus, hardness, density, and the like.

The equivalent ratio of the hydroxyl group of the polyol component containing the polyol compound to the isocyanate group of the polyisocyanate component (Isocyanate index [NCO index]) is 0.85 to 1.15 (8.55 in the index notation). To 115), and more preferably approximately equivalent weight 0 (100 in the exponential notation). When water is used as the blowing agent, the amount of 7K used is usually 0.1 to 8 parts by weight, preferably 2 to 4 parts by weight, based on 100 parts by weight of the polyol compound. The amount of the catalyst to be used is generally 10 parts by weight or less, preferably 0.05 to 1.0 part by weight, based on 100 parts by weight of the polyol compound. The amount of the foam stabilizer used is usually 0.01 to 5 parts by weight (in the case of a foam stabilizer diluted with a plasticizer or the like, based on the active ingredient) with respect to 100 parts by weight of the polyol compound. Preferably it is 0.1 to 2 parts by weight. In addition to the above-mentioned components, various additives such as an emulsifier, an antioxidant, an ultraviolet absorber, an antioxidant, a filler, a flame retardant, a plasticizer, a colorant, a fungicide and an antibacterial agent are added to the polyurethane foam raw material. Agents can be added as needed.

Polyurethane foam raw materials containing the above-mentioned various components are available in various types depending on the use to which the sheet cushion pad is applied. It is molded into a seat pad in a predetermined mold for the dog. A usual method can be adopted as a molding method. For example, a polyol compound, a foaming agent, a catalyst, a foam stabilizer, a cross-linking agent, and, if necessary, an additive are preliminarily mixed into a polyol component in a predetermined amount, and then the mixture is mixed with a polyol component. Use a polyurethane foaming machine or stirrer for the fanate component Then, the polyurethane foam raw material obtained by rapid mixing is poured into a mold and demolded after a predetermined time to obtain a seat cushion. A soft polyurethane foam as a pad is obtained.

The fit of the seat cushion knob when seated varies depending on the thickness of the skin layer formed as the polyurethane foam surface layer during molding. The thickness and properties of the skin layer vary depending on the packing ratio during molding, the mold temperature during molding, the reaction speed of forming the polyurethane foam, and the like. Under the pad forming conditions of about 1.1 to 1.3 and the mold temperature of about 50 to 70 ° C, the thickness and properties of the skin layer do not change much. The thickness of the skin layer is about 1 Omm for commonly used sheet pads, and the core density of the foam is about 80 to 90% of the total density including the skin layer, and is about 85% in most cases. Becomes

Seat Cushion ,. On the back of the pad, for example, a resin supporter made of polyurethane, polypropylene, polyethylene, polystyrene or its foam, or a sabot (reinforcing material) such as PP cloth, coarse blanket, or non-woven fabric, is pre-formed at the time of molding. It is also possible to laminate by an integral molding method that inserts into the mold or by bonding after foam molding.

A seat or the like that is actually mounted in a car rain is provided with the seat cushion pad of the present invention, which is covered with outer layers such as genuine leather, moquettes, tricots, jerseys, and fabrics. When covering the outer layer with the seat cushion pad, it is also preferable to attach one member of the hook-and-loop fastener to the seat cushion pad by bonding or the like. .

[Example]

Hereinafter, examples and the like that specifically show the configuration and effects of the present invention will be described. The methods for evaluating physical properties and the like in Examples and the like are as follows.

[Physical properties of seat cushion pad]

a) 25% hardness: This is the load when the seat cushion pad is compressed by 15% with a pressure plate having a diameter of 200 mm (based on JISK640).

b) Core density (k / m ³ ): Seat cushion. The core of the pad Density.

C) Rebound resilience of core layer ''

A measurement sample of 100 mm × 100 mm × 50 mm (t) was taken from the core portion (excluding the skin layer) of the seat cushion pad, and the measurement was performed in accordance with JIS-6400. The removed skin layer is about 1 Omm.

[Vibration transmissibility characteristics of seat cushion pad]

The resonance frequency (Hz) was obtained from the vibration transmissibility curve obtained by performing a forced vibration test with an amplitude of ± 2.5 mm by applying a 50 kg iron-type press plate in accordance with JASO B-407. , Resonance magnification, and vibration transmissibility (6 Hz, 1 OHz) were measured. For the measurement of vibration characteristics, a sheet cushion vibration tester C-1002 DL (manufactured by Ito Seiki Co., Ltd.) was used.

[Hyoko Hyo feeling]

For a sample with a thickness of 65 mm, a seat cushion covered with a polyurethane foam pad skin material was actually mounted on a vehicle, and five panelists were riding and running, and a sensory evaluation was performed using an actual vehicle.

[Free foam height]

Based on the formulation shown in (Table 1) above, the total amount of the polyol components excluding the isocyanate component was weighed to about 600 g (equivalent to 5 times of about 107 g per use). And placed in a cylindrical container with a capacity of 1 L, and using an auto homomixer AM-M (special machine Kako Co., Ltd.), a diameter of 4 Omm. A total of 12 sheets were attached, and the mixture was stirred at 3500 rpm for 5 minutes to adjust the polyol component. Leave this voryl component for 12 to 20 hours and leave it as a frustoconical container with a bottom diameter of 105 mm, an opening diameter of 14 Omm, and a height of 195 mm. ) Was used as the foaming container, and the amount was weighed into this foaming container, and the mixture was stirred with the above-mentioned auto homomixer AM-M at 3500 rpm for 5 seconds, and immediately NCO index x = l. An isocyanate component was added so that the value became 0 (100 in the exponential notation), and the mixture was stirred at 3500 rpm for 7 seconds to form a foamed composition. The foaming composition is mixed to a total amount of 147.3 g, and the polyol component and the isocyanate component are both adjusted to 25 ° C before use. Used. As shown in FIG. 2, the free foamed foam height was determined by placing a foamed container containing a foam on a horizontal table and measuring the height using a gold scale. Figure 2 shows the measurement of the free foam height. The measurement results of the free foam height (unit: mm) are shown in (Table 2) and (Table 3). Free foaming was performed 5 times, and the maximum value, the minimum value, and the average value of 5 times were shown. The x / y ratio of the foam stabilizer is preferably 0.75 / 0.25 or more.

[3. Production of pad)

The properties of the raw materials used in the following examples are summarized in (Table 4). In Table 4, the x / y ratio and m / n ratio of the foam stabilizer are values measured by NMR. The measurement was carried out using FT-NMR DPX 400 S (manufactured by BURKER), and the foam stabilizer was measured as a 2% by weight solution of heavy-mouthed form. x / y and m / n are respectively

x / y = [(P 3-1.5 XP 5) / 6] / (P 5/2)

m / n = C (P 1 -P 2-P 5) / 4] / (P 2/3)

I asked for it. Here, Pl, P2, P3, and P5 are the following HP 1 in (I-Dai 2): — OCH ₂ — group, H- (〇CH—) group (3.0 to 4.0 ppm)

P 2: C— CH ₃ group H (around 1. l ppm)

P 3: H of _three Si-CH groups (around O ppm)

P 5: H of S i -CH ₂ — group in X group (around 0.45 ppm)

Is the integral value of.

(Example 1)

The formulation used to produce the seat cushion pad of Example 1 is shown in (Table 5). The compounding ratio was expressed in parts by weight with the total of the polyol compounds being 100 parts by weight. The components described in (Table 5) were blended in the usual manner at the weight ratios shown in the same table, mixed uniformly, and then poured into a mold of a predetermined shape, foamed and cured, and then foamed and cured. I got it.

For the seat cushion pad, a seat cushion with a thickness of 65 mm was manufactured. This sheet cushion pad uses a sheet cushion pad mold for an actual vehicle, and a polypropylene net Nisseki Conwed Net (Nisseki Goho) is used as a support member on the bottom side. Tree Products Co., Ltd.) was used.

The shape of the seat cushion pad with a seat surface thickness of 65 mm is shown in Fig. 1. Fig. 1 (A) shows the dog in the front-rear direction, that is, the cross section in the front-rear direction when a person is seated. Figs. 1 (B) to (D) show the positions (a) to (c) in Fig. 1 (A). 5 shows a cross section in the left-right direction of FIG. 5, where (a) is a seat surface portion and the thickness is 65 mm.

The position where the hardness of the seat cushion pad is measured is the seat surface, as shown in FIG. The position below the hip point where the elastic modulus of the core layer was measured is near this hardness measurement position.

The results of measuring the physical properties of the obtained sheet cushion pad and the results of evaluating the feeling of chill are shown in Table 6. Fig. 3 shows a graph of the measured vibration transmissibility.

As shown in (Table 6), the seat cushion pad of the present invention has a resonance frequency, a resonance magnification, and a rebound resilience of the core layer within a predetermined range. The chick feeling was good, and the fit when sitting was also good.

On the other hand, in Comparative Example 1, the resonance magnification was large, and it did not satisfy the feeling of humming when used as an actual sheet cushion pad.

[Industrial applications]

INDUSTRIAL APPLICABILITY The sheet cushion pad of the present invention can be used for a sheet cushion pad for a vehicle, particularly an automobile, which vibrates when used.

(Table 2)

Seiyanagi J Product name Sanofiya Old

Trading value Flat ± 5ί

0 Λ Γ

9bo bunch Ο

F Retaukonino Kunrikono 4 ϋ. L i b 4.b

0 π

Sr Bundle Letaukoninokun Ο 0

Ricono 44 2 d 3 ΰδ.U east ■ -.1

SF 2961 ゥ Konino Kunrikono ο

242 2 3 2 2 3 4.8

―, _-. * · "* I i, 10 ITβ 8680" One note --- Note 4 ά i Ό 2 3 5.4

L 53bb says 2 ^ L two-car π ο ο ο / 1

1 L 2 3 3

L 5309 days ^ 2.2 cars 0 ο ο ο

240 2 2 3

PDV OV / I Γ ο ο Ο Α Γ Ο 1))

Toretau _J-ichi / Kunrikono L L L (J D Ζ 丄. 4

SF 2969 Toray Dow Corning Silicon 2 2 5 2 05 2 1 7.2

SF 2964 Toray Downcon Silicon 2 24 2 06 2 16.0

-9T-

(εhara) l0 / l0dT / 13d S9.690 / Z0 OAV (Table 4) Raw material name Supplier Description

EP 901 3 学学 PPG, OHV = 24mgKOH / g,

EP 3033 PPG, 0HV = 34mgK0H / g

POP 3690 polymer polyol, 0HV = 2 lmgKOH / g

POP 3128 Sanshogaku polymer polyol, 0HV = 28mgKOH / g

t- ¹

SF 2962 Toray Dow Corning Silicon Silicon-based foam stabilizer ij ( _x = 0.77, y = 0.23, m = 0.19, n = 0.81)

SRX-274C 桌 Reduced Silicon Silicon Silicone foam stabilizer ( _x = 0.76, y = 0.24, m = 0.19, n = 0.81)

EP— 505 S Tri-removal trifunctional EO / PO copolymer OHV = 52mgKOH / g EO = 75mo 1%

TEDA L 33 Tosoh third grade Amin horn! ^ Certain

N i ax A- 1 day 2 car 3rd grade Amin horn certain

MC 73 Mitsusho MD I

TM-20 Sangei TD I / MD 1 = 80/20

(Table 5)

(Table 6)

I

I— ^L

00

I: 1 ^ 〇0 / 〇1 ^ today;

Claims

The scope of the claims

1. A seat cushion pad made of polyurethane foam having a skin layer and a core layer formed by injecting a polyurethane foam material into a mold, and having a single-layer seating surface,

The resonance magnification at 2 to 4 Hz measured by a forced vibration test performed at 0.5 mm with a 50 kg iron-plate type press plate was 4 or less, and the rebound resilience of the core layer was 50%. The raw material of the polyurethane foam has a hydroxyl value of 20 to 40 mg KOH / g as a polyol component, and a polyether polyol having an ethylene oxide unit at the end thereof has a weight of 60 to 80%. Parts, a polymer having a hydroxyl value of 15 to 30 mg K 0 HZ g 40 to 20 parts by weight, a silicone foam stabilizer, a foaming agent, and diphenylmethanediiso as a polyisocyanate compound Seat cushion nose characterized by the use of cyanates. Good.

2. The polyurethane foam raw material is a copolymer of ethylene oxide and propylene oxide having a molecular weight of 100 to 500, and the copolymerization ratio of ethylene oxide is 50% by weight or more. 2. The sheet cushion according to claim 1, wherein the polymer is 0.5 to 5 parts by weight based on 100 parts by weight of the polyol component as a foam breaking agent. Good.

3. The sheet cushion pad according to claim 1, wherein the silicone foam stabilizer has an average free foam height of not less than 25 mm.

4. The silicone foam stabilizer is represented by polydimethylsiloxane or (Chemical Formula 1), in which the equivalent ratio of ethylene oxide unit m to propylene oxide unit n in the copolymerized polyester is m / n. Is preferably from 0.4 / 0.6 to 0.6, 0.5 / 0.95. (Chemical formula 1)

CH ₃ CH ₃ CH ₃

CH -Si-0 Si-0 Si-0 Si-CH ₃

CH ₃ , X (E0) _m (P0) _n -R / _y CH ₃

(In (Chemical Formula 1), X is an organic residue having 1 to 4 carbon atoms, R is an alkyl group or an acyl group, X is 80 to 250, and y is 0 to 50.)

5. The seat cushion pad according to any one of claims 1 to 4, wherein the foaming agent is water, and the amount of the foaming agent is 0.1 to 8 parts by weight based on 100 parts by weight of the polyol compound.

6. The seat cushion pad according to claim 5, wherein the amount of the water added is 2 to 4 parts by weight based on 100 parts by weight of the polyol compound.

7. The sheet cushion pack K according to any one of claims 1 to 6, wherein the addition amount of the silicone foam stabilizer is 0.1 to 2 parts by weight based on 100 parts by weight of the polyol compound. .