JP2000095048A - Shock absorbing pad - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ideal stress-stroke wave form required for a shock absorbing pad by making the pad of foam resin material, and by partially, in the compression axis direction, changing or increasing cross sections in the compression axis and vertical directions. SOLUTION: Shock absorbing pads 1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 1I are made of hard polyurethane foam, their cross sections in the compression axis X and vertical directions increase and change partially in the compression axis X, and thereby a stress-stroke (F-S) wave form becomes almost linear. The hard polyurethane foam provides almost constant compression stress regardless of compression stroke in a given range of the compression stroke, surface load is proportional to pressurized surface, cross section in the compression axis X and vertical directions is changed, and thereby, the pads can be designed so that compression stroke is proportional to compression stress. Thus, an ideal F-S wave form can be easily provided, by designing the shape, for example, by providing a tapered portion, a recessed part, a notch, or a step portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock-absorbing pad, and more particularly to a shock-absorbing pad which is incorporated in an interior of an automobile and protects an occupant in the event of a vehicle collision. The present invention relates to a shock-absorbing pad incorporated in a center pillar garnish or the like and used for protecting a passenger's chest or shoulder.

[0002]

2. Description of the Related Art One of the material characteristics required of a shock absorbing material for absorbing the shock of the occupant's chest or shoulder at the time of a vehicle collision is that stress is linearly applied to a compression stroke (compression strain). FS waveform (stress-stroke waveform) in which the stress is proportional to the developed characteristics, ie, the compression stroke
Conventionally, such a linear F
In many cases, an iron plate, a semi-rigid polyurethane foam, or the like is used as the material exhibiting the -S waveform.

[0003]

However, among the conventional shock absorbers, the iron plate has a linear FS waveform as shown in FIG. 2A, but the iron plate is heavy. Therefore, there is a disadvantage that the weight of the vehicle is increased.

On the other hand, semi-rigid polyurethane foam F-
The S waveform is as shown in FIG. 2 (b), which is linear in the initial stage of compression (the range where the compression stroke is small). However, when the compression stroke is increased, the FS waveform is shifted from the required waveform. is there.

Although a rigid polyurethane foam is also used as a general cushioning material, a rigid polyurethane foam having a compressive stress of 8 even if it is a low-hardness rigid polyurethane foam having a compressive stress of about 3.0 kg / cm ^2. .0
Even a rigid polyurethane foam having a high hardness of about kg / cm ² has a shape as shown in FIG. 2C when the FS waveform is schematically shown, and greatly deviates from the required waveform.

The present invention solves the above-mentioned conventional problems and provides a lightweight shock-absorbing pad made of a foamed resin material, which shows an ideal FS waveform required for the shock-absorbing pad. The purpose is to do.

[0007]

The shock absorbing pad of the present invention is made of a foamed resin material, and has a cross-sectional area in a direction perpendicular to a compression axis direction at least partially changed in the compression axis direction.
Preferably, the relationship between the compression stress and the strain in the compression axis direction is substantially linear.

Even if the pad is made of a foamed resin material that does not exhibit a linear FS waveform, the cross-sectional area in the direction perpendicular to the compression axis direction at least partially changes, preferably increases, in the compression axis direction. By doing so, the relationship between the compressive stress and the strain in the compression axis direction, that is, the FS waveform can be adjusted, and can be preferably made substantially linear.

The shock absorbing pad of the present invention is preferably made of a rigid polyurethane foam having a FS waveform as shown in FIG. 2 (c). Alternatively, by devising the shape by providing a step portion or the like, it is possible to easily provide a shock absorbing pad showing an ideal FS waveform.

[0010] The shock absorbing pad of the present invention is particularly used as an automobile interior material for a shock absorbing pad for protecting an occupant for absorbing an impact received by an occupant in the event of a vehicle collision, especially a door trim or a center pillar garnish of an automobile. It is extremely useful industrially as a shock-absorbing pad that is incorporated and used to protect the occupant's chest or shoulder.

In the present invention, the FS of the material itself is used.
The waveform (that is, the relationship between the compression stress in the compression axis direction and the compression strain (stroke)) is 50 mm × 50 m as shown in FIG.
The sample 11 having a thickness of m × 50 mm is sandwiched between the pressing jigs 12 and 13 and is obtained by a stress with respect to a compression stroke when the sample 11 is compressed at a compression speed of 50 mm / min.

The FS waveform of the shock-absorbing pads 1A to 1I shown in FIGS. 1A to 1I described below is different from the shock-absorbing pads 1A to 1I in FIG.
1I is sandwiched between the pressing jigs 12 and 13, and can be obtained in the same manner as described above.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1A to 1I and FIG. 4B are schematic sectional views showing an embodiment of the shock absorbing pad of the present invention. In FIG. 1, an arrow X indicates a compression direction.

The shock absorbing pads 1A, 1B, 1C, 1D, 1E, 1F, 1 shown in FIGS.
G, 1H, 1I and 1 are made of a rigid polyurethane foam, and have a cross-sectional area perpendicular to the compression axis direction X (hereinafter sometimes referred to as “pressing area”) in the compression axis direction X.
It is designed to increase or change at least partially, so that the FS waveform is substantially linear. As shown in FIG. 2C, the rigid polyurethane foam suitable for the present invention exhibits a substantially constant compressive stress in the range of the compression strokes a and b, regardless of the compression stroke. Therefore, it can be considered that the surface load is proportional to the pressing area, and by changing the pressing area corresponding to the compression stroke, that is, by changing the cross-sectional area in the compression axis direction X and the vertical direction,
The compression stroke is proportional to the compression stress, ie, F
-S Can be easily designed so that the waveform is linear.

That is, as shown in Example 2 below, a rigid polyurethane foam suitable for the present invention is 50 mm × 50 mm.
When the FS waveform of the cubic test piece having a thickness of 50 mm × 50 mm is measured by the method shown in FIG. 3, as shown in FIG. In the proportional relationship, the stress is substantially constant regardless of the stroke in the range of the strokes a to b, and the stress and the stroke again become proportional in the range of the strokes b to c. Using such a rigid polyurethane foam, as shown in FIG. 4B, the same cross-sectional shape is formed in the upper part (left part in FIG. 4B) in the range of 0 to a, and in the subsequent range of a to b, As shown in FIG. 4 (c), the shock absorbing pad 1 has a shape having a gradually increasing cross-sectional area and a substantially trapezoidal cross-section (substantially frustoconical shape) having the same cross-sectional shape in the range of b to c. , A-b
The FS waveform in the range of the stroke can be improved to obtain an ideal FS waveform that is entirely linear.

In the shock absorbing pad of the present invention, the pressing area may be designed so that a desired FS waveform can be obtained in a predetermined compression stroke according to required characteristics, and the shape is not particularly limited. . Examples of the shape of the shock absorbing pad of the present invention include, for example, FIGS. 4 (b), 1 (a), (b), and
Shock absorbing pads 1, 1A, 1B, 1H having a trapezoidal cross section or a substantially trapezoidal cross section as shown in (h); concave portions having a triangular or trapezoidal cross section in the center as shown in FIGS. Shock-absorbing pads 1C, 1D on which 2C, 2D are formed; shock-absorbing pads 1E, 1F, 1G having a triangular or substantially triangular cross section as shown in FIGS. 1 (e), (f), (g). Can be Furthermore, as an interior material of an automobile, there is a case where it is attached to a door trim surface, and in this case, it is desirable that one surface has a shape along the shape of the door trim,
For example, a shock absorbing pad 1I having an irregular shape as shown in FIG. 1 (i) may be mentioned, but the present invention is not limited thereto. In the case of a shock absorbing pad provided with a tapered portion or a notch, the angle of the inclined portion (the angle θ in FIG. 1) is desirably 15 ° or more.

As described above, the material of the shock-absorbing pad of the present invention is F-type as shown in FIG.
It has no S waveform, that is, a yield point (in the FS waveform, a point at which stress once rises and then falls with respect to strain), and in the initial stage of compression, strain and stress are almost proportional and reach a certain stress value. After that, the stress is substantially constant with respect to the change in strain, and it is preferable to use a rigid polyurethane foam having the characteristic of increasing the stress again at the end of compression.

As such a rigid polyurethane foam, when producing a rigid polyurethane foam by foaming and reacting a polyurethane foam foaming raw material containing a polyhydroxy compound and a polyisocyanate compound as main components, the foaming raw material has an average particle size. A powder having a particle size of 0.05 to 100 μm is added in an amount of
Examples include those manufactured by blending parts by weight. In the case of this rigid polyurethane foam, the powder is dispersed and present in the cell membrane of the rigid polyurethane foam.
As shown in (c), the stress is constant with respect to the change in strain, no yield point is observed, and the energy absorption efficiency is high.

That is, when a general rigid polyurethane foam is compressed, cell breakage occurs randomly, and F
Although some of the rigid polyurethane foams have a yield point in the -S waveform and the stress is not constant with respect to the change in strain, the rigid polyurethane foam causes cell destruction sequentially from the side to which compressive strain is applied. ), There is no yield point, strain and stress are almost proportional in the early stage of compression, and after reaching a certain stress value, the stress becomes substantially constant with respect to the change in strain,
Figure 4 shows an FS waveform where stress increases at the end of compression.

The mechanism of maintaining a constant stress with respect to a change in strain due to the presence of the powder in the cell film has not yet been sufficiently elucidated, but the existence of a foreign powder is not clear. It is presumed that this is due to the constant breaking stress of each cell. That is, it is considered that the presence of the powder becomes a stress concentration point in each cell, and an effect as if a notch is formed appears.

Hereinafter, a method for producing such a rigid polyurethane foam will be described.

The rigid polyurethane foam contains a polyhydroxy compound and a polyisocyanate compound as main components, and optionally contains a powder having a specific particle size, a catalyst, a foaming agent, a foam stabilizer, and other auxiliaries. It is produced by foaming and reacting the foamed polyurethane foam raw material.

The polyhydroxy compound is not particularly restricted but includes, for example, polyether polyols obtained by ring-opening addition polymerization of glycerin, sucrose, ethylenediamine or the like with an alkylene oxide such as ethylene oxide or propylene oxide; adipic acid, Polyester polyols obtained by a polycondensation reaction of a polybasic acid such as succinic acid with a polyhydroxyl compound such as ethylene glycol or propylene glycol, or a ring-opening polymerization of lactones; and the like. More than one species can be used in combination.

In order to improve the heat resistance of the obtained rigid polyurethane foam, the average OH value of all the polyhydroxy compounds is desirably 200 or more, preferably 300 or more.

Examples of the polyisocyanate compound include aromatic isocyanates such as diphenylmethane diisocyanate and tolylene diisocyanate; alicyclic isocyanates such as isophorone diisocyanate; aliphatic isocyanates such as hexamethylene diisocyanate;
One of these crude products and the like can be used alone or in combination of two or more.

The amount of the polyisocyanate compound used relative to the total amount of the compound having active hydrogen such as polyhydroxy compound and water, that is, the isocyanate index, is 80 to 13 in the case of producing a rigid rigid polyurethane foam.
In the case where an isocyanurate-modified rigid polyurethane foam is produced, the range is preferably from 150 to 350.

The powder having a specific particle size to satisfy the FS waveform has an average particle size of 0.05 to 100.
μm, preferably 0.5 to 50 μm, more preferably 1 μm
It is necessary to use one having a size of ３０30 μm. When the average particle size of the powder used is smaller than 0.05 μm, a stress concentration point cannot be formed, and when the average particle size exceeds 100 μm, it becomes difficult to use the powder in a commonly used urethane foaming machine.

The powder is not particularly limited as long as it has the above-mentioned average particle size. Examples of the powder include inorganic compounds such as calcium carbonate and aluminum hydroxide;
Metals such as iron and aluminum; and organic substances such as polyamide, polyvinyl chloride and melamine.
The species can be used alone or in combination of two or more.

The amount of the above-mentioned powder to be used should be in the range of 1 to 200 parts by weight, preferably 2 to 50 parts by weight, more preferably 5 to 50 parts by weight based on 100 parts by weight of the total polyhydroxy compound. . If the amount of the powder used is less than 1 part by weight based on 100 parts by weight of the total polyhydroxy compound, the stress concentration point is too small to make the stress against strain inconsistent, while the amount exceeds 200 parts by weight. If mixed
When the rigid urethane foam is formed by stirring, the viscosity of the reaction solution increases remarkably, the mixing / stirring efficiency decreases, and the non-reactive components increase. As a result, the reaction completeness is reduced, resulting in insufficient strength and the like.

As the catalyst, a known catalyst used for producing a rigid polyurethane foam can be used. For example, organometallic compounds such as dibutyltin dilaurate, lead octoate and stannas octoate; amine compounds such as triethylenediamine and tetramethylhexamethylenediamine are used. (Propyl) hexahydro-s-triazine, potassium acetate, potassium octylate and the like used for isocyanurate modification can also be used.

As the foaming agent, any of those used in the production of rigid polyurethane foams can be used. For example, water, trichlorofluoromethane, 1,1,1
Chlorofluorocarbons such as 2-trichloro-1,2,2-trifluoroethane; hydrochlorofluorocarbons such as dichlorotrifluoroethane and dichlorotetrafluoroethane; hydrochlorocarbons such as methylene chloride; and hydrochlorocarbons such as hexafluoropropane. Hydrocarbons such as fluorocarbons and pentane can be used. Among these, water is particularly preferable in view of the influence on the environment due to diffusion into the atmosphere and the like.
In general, when a large amount of water is used, a large amount of heat is generated at the time of foaming / reaction, and scorch is easily generated inside the obtained rigid polyurethane foam. The calorific value is small,
There is also an advantage that scorch can be prevented. The amount of water was 0.1% with respect to 100 parts by weight of the polyhydroxy compound.
A range of 5 to 10 parts by weight is preferred.

When a foam stabilizer is compounded, the foam stabilizer is
Polyoxyalkylene-based ones such as polyoxyalkylene alkyl ethers, silicone-based ones such as organopolysiloxane, and the like, which are effective for rigid polyurethane foams, can be used,
In the present invention, the surface tension is 16 to 22 dyn / c.
It is preferred to use a foam stabilizer in the range of m, especially 18 to 21.5 dyn / cm. By using this kind of foam stabilizer, the desired rigid polyurethane foam can be reliably obtained. If a foam stabilizer having a surface tension of less than 16 dyn / cm is used, phenomena such as cell roughening may occur. If the foam tension is more than 22 dyn / cm, the cells constituting the obtained rigid polyurethane foam become close to spherical and have a constant shape. Buckling may not occur stably with respect to stress.

That is, as the cell becomes closer to a sphere, the buckling stroke becomes shorter with respect to the input from the major axis direction of the cell, and as a result, the macroscopic "strain-stress" characteristic of the foam, which is an aggregate of cells, is also obtained. It is considered that the buckling region where the stress is constant, that is, the effective strain range is reduced, and the energy absorption efficiency is reduced. Generally, the obtained stress itself is related to the major axis / minor axis ratio of the cell, and when the ratio is large, the major axis direction shows the highest stress. For this reason, in the present invention, the ratio of the major axis / minor axis of the obtained rigid polyurethane foam is preferably in the range of 1 to 5, particularly 1.5 to 4.

In the foaming raw material, an arbitrary component other than the above components, for example, a flame retardant can be used as long as the object of the present invention is not hindered.

For foaming and reaction, the same method as in the production of ordinary rigid polyurethane foam can be adopted.
Increase the foaming speed by 10 to 140 seconds, especially 15 to 1
The adjustment is preferably performed so as to be in the range of 10 seconds, whereby the intended rigid polyurethane foam can be obtained reliably. On the other hand, if the rise time is shorter than 10 seconds, a necessary and sufficient stirring time cannot be obtained, and scorch may be easily generated in the foam. On the other hand, if the time exceeds 140 seconds, the cell becomes nearly spherical, and the energy absorption efficiency may decrease as described above.

When the rigid polyurethane foam thus obtained is compressed at a temperature of -30 to 100 ° C., it has no yield point as shown in FIG. Thus, the stress is as constant as possible, and the cell is sequentially destroyed from the strain side. Therefore, it has excellent compression characteristics and high impact energy absorption efficiency. Specifically, according to the method for producing a rigid polyurethane foam,
A specimen having a width of 50 mm, a length of 50 mm and a height of 30 mm was compressed at a compression rate of 50 mm / in the height direction (cell major axis direction).
When compressed under the compression condition of sec, the compression ratio is 10 to 65%
, A rigid polyurethane foam having a stress that is substantially constant in the range of ² to 8 kg / cm ² (the fluctuation of stress is ± 0.5 kg / cm ² ) can be produced.

The rigid polyurethane foam is JIS-A-951 in order to secure the properties as a shock absorber.
The foam density measured according to 4 is 25-90 kg /
It preferably has a value in the range of m ³ , in particular 30 to 80 kg / m ³ .

The above-mentioned rigid polyurethane foam is a rigid polyurethane foam suitable as a constituent material of the impact-absorbing pad of the present invention, and the impact-absorbing pad of the present invention is manufactured by any of the above-mentioned rigid polyurethane foams. It is not limited. That is, FIG.
Even if the rigid polyurethane foam does not show a linear FS waveform as shown in (c), by changing the shape, that is, the cross-sectional area in the direction perpendicular to the compression axis direction changes in the compression axis direction. By adjusting the degree of compression, it is possible to make the relationship between the compressive stress and strain in the compression axis direction substantially linear, and the object of the present invention can be achieved even with other rigid polyurethane foams. However, if the rigid polyurethane foam is used, the present invention can be easily realized with a relatively independent shape, and is practically preferable.

[0040]

The present invention will be described more specifically below with reference to examples and comparative examples.

Example 1 A shock absorbing pad 1I made of a rigid polyurethane foam and having the shape shown in FIG. 1 (i) (in FIG. 1 (i), the width W =
100 mm, thickness D = 40 mm), the compression speed is 6
The FS waveform when the entire surface was compressed in the direction of arrow X at m / sec was examined, and the results are shown in FIG. From FIG. 5, it can be seen that this shock absorbing pad 1I exhibits a substantially linear FS waveform.

Example 2, Comparative Example 1 A rigid polyurethane foam was produced with the composition shown in Table 1.

First, 200 g of a polyhydroxy compound was weighed into a 1-liter paper cup, a predetermined amount of a catalyst, a silicone foam stabilizer and water were added thereto, and the mixture was stirred for about 10 seconds with a propeller-type stirrer. The powder was added and thoroughly mixed and stirred for about 30 seconds.

Next, a predetermined amount of crude diphenylmethane diisocyanate was added to the homogeneous mixture, and the mixture was rapidly stirred at room temperature for about 5 seconds.
The mixture was poured into a polyethylene bag set in a m × 250 mm × 250 mm wooden mold and foamed and reacted at room temperature. The obtained foam is placed in an oven at 50 ° C. for about 1 hour.
After-curing was performed for 0 minutes to obtain a rigid polyurethane foam. The time required from the start of the high-speed stirring after the addition of the crude diphenylmethane diisocyanate to the end of the apparent increase in the volume of the reaction solution was taken as the rise time (foaming / curing time) of each foam, and this value is shown in Table 1.
Also, the foam density of the obtained foam was determined according to JIS.
-A-9514, and the ratio of the major axis / minor axis of the cells of the foam was measured by actual measurement of an enlarged photograph, and the results are shown in Table 1. These measurements were carried out after the foaming and curing of the foam was completed, and then left for 3 days.

[0045]

[Table 1]

Using each rigid polyurethane foam, a cubic test piece having a thickness of 50 mm × 50 mm × 50 mm was prepared, and the FS waveform of this test piece was measured by the method shown in FIG. In the rigid polyurethane foam No. 2, as shown in FIG. 4A, the stress and the stroke are substantially proportional in the range of the compression strokes 0 to a, and the stress is substantially constant in the range of the strokes a to b regardless of the stroke. In the range of the strokes b to c, the stress and the stroke again have a proportional relationship. As shown in FIG. 6A, the rigid polyurethane foam of Comparative Example 1 had a yield point. Also, using such a rigid polyurethane foam, FIGS.
As shown in (b), the upper portion (left portion in FIGS. 4 (b) and 6 (b)) has the same cross-sectional shape in the range of 0 to a, and the cross-sectional area gradually increases in the subsequent range of a to b. Then, shock absorbing pads 1 and 10 having a substantially trapezoidal cross section (substantially frustoconical shape) having the same cross sectional shape in the range of b to c are manufactured (however, the shock absorbing pads 1 and 10 in FIG. The shock absorption pad 1 using the rigid polyurethane foam of Example 1 was measured by measuring the FS waveform in the same manner as the shock absorption pad 10 of FIG. 6 (b). As shown in FIG. 4C, the FS waveform in the range of strokes a to b is improved,
Although an ideal linear FS waveform could be obtained as a whole, the shock absorbing pad 10 using the rigid polyurethane foam of Comparative Example 1 exhibited sufficient performance as shown in FIG. I couldn't. Therefore, in order to produce an ideal FS waveform shock absorbing pad as shown in FIG. 4C using the rigid polyurethane foam of Comparative Example 1, it is necessary to further devise its shape.

[0047]

As described in detail above, according to the shock absorbing pad of the present invention, it is a lightweight shock absorbing pad made of a foamed resin material, and an ideal linear F-type required for the shock absorbing pad. An impact-absorbing pad exhibiting an S waveform can be provided.

The shock-absorbing pad of the present invention is particularly preferably constituted by using a rigid polyurethane foam. By using a rigid polyurethane foam and appropriately adjusting the shape, the FS waveform of the shock-absorbing pad can be adjusted. Can be adjusted easily.

The shock-absorbing pad of the present invention is incorporated in an interior material of an automobile, in particular, into an impact-absorbing pad for protecting an occupant for absorbing an impact received by an occupant in a vehicle collision, especially an automobile door trim, a center pillar garnish and the like. Therefore, it is extremely useful industrially as a shock absorbing pad used for protecting the occupant's chest or shoulder.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a shock absorbing pad of the present invention.

FIG. 2 is a graph showing FS waveforms of various materials.

FIG. 3 is a schematic cross-sectional view showing a method of measuring an FS waveform.

4A and 4B are diagrams illustrating the principle of adjustment of the FS waveform in Example 1. FIG. 4A is a graph showing the FS waveform of a cubic rigid polyurethane foam test piece, and FIG.
FIG. 4B is a cross-sectional view showing a shock-absorbing pad produced using the rigid polyurethane foam, and FIG.
It is a graph which shows the FS waveform of the shock absorption pad of (b).

FIG. 5 is a graph showing the results of Example 1.

6A and 6B are diagrams illustrating an FS waveform in Comparative Example 1. FIG. 6A is a graph showing an FS waveform of a cubic rigid polyurethane foam test piece, and FIG. FIG. 6C is a cross-sectional view showing a shock absorbing pad made using a rigid polyurethane foam, and FIG. 6C is a graph showing an FS waveform of the shock absorbing pad of FIG. 6B.

[Explanation of symbols]

1,1A, 1B, 1C, 1D, 1E, 1F, 1G, 1
H, 1I Shock absorbing pad 2C, 2D recess

Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court II (Reference) // (C08G 18/28 101: 00)

Claims (10)

[Claims] 1. A shock absorbing pad comprising a foamed resin material, wherein a cross-sectional area in a direction perpendicular to a compression axis direction is at least partially changed in the compression axis direction. 2. The shock absorbing pad according to claim 1, wherein a cross-sectional area in a direction perpendicular to the compression axis direction is at least partially increased in the compression axis direction. 3. The shock absorbing pad according to claim 1, wherein the relationship between the compressive stress and the strain in the compression axis direction is substantially linear. 4. The shock-absorbing pad according to claim 1, wherein the shock-absorbing pad is made of a rigid polyurethane foam. 5. The foam according to claim 4, wherein the rigid polyurethane foam is obtained by foaming and reacting a polyurethane foam foaming raw material containing a polyhydroxy compound and a polyisocyanate compound as main components. An impact-absorbing pad comprising 0.05 to 100 μm of a powder in an amount of 1 to 200 parts by weight per 100 parts by weight of the polyhydroxy compound. 6. The method according to claim 5, wherein the rigid polyurethane foam has a stress when compressed at −30 to 100 ° C.
A shock absorbing pad characterized by having no yield value in a compression strain curve. 7. The impact-absorbing pad according to claim 5, wherein a foam stabilizer having a surface tension of 16 to 22 dyn / cm is added to the foaming raw material. 8. The method according to claim 5, wherein the foaming rate in the foaming / reaction is 10 times in rise time.
A shock-absorbing pad characterized by a range of seconds to 140 seconds. 9. The shock-absorbing pad according to claim 5, wherein water is used as a foaming agent. 10. The shock-absorbing pad according to claim 1, wherein the shock-absorbing pad is a shock-absorbing pad for an automobile interior.