JPH09131823A - Sheet pad for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress fogging of a window glass and discoloration of a skin material and to exhibit flame retardancy by performing integral foam molding of a non-woven fabric prepd. by heat welding a polyester fiber web with a low m.p. polyester cotton at the site where a flexible polyurethane sheet pad is brought into contact with a metal spring. SOLUTION: A sheet pad is constituted by performing integral foam molding of a thermally bonded non-woven fabric wherein a polyester fiber and a low m.p. polyester cotton are raw materials at the site where a flexible polyurethane foam is brought into contact with a metal spring. Namely, the thermally bonded non-woven fabric cut to a specified dimension is set on the inner face of a top force of a mold for foaming and a stock soln. for a flexible polyurethane foam is poured in a bottom force and the top force is closed to perform integral foam curing. The thermally bonded non-woven fabric is obtd. by mixing the low m.p. polyester cotton in a web consisting of a polyester fiber, etc., and heating it to stick the points of intersection. It is pref. that the m.p. of the web of a polyester fiber is 255-260 deg.C and the m.p. of the low m.p. polyester cotton is 100-110 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle seat pad, and more particularly to improvement of flame retardancy of a soft polyurethane seat pad mounted on a cushion panel having a metal spring.

[0002]

2. Description of the Related Art Conventionally, an automobile seat is manufactured by placing a seat pad, which has been molded in a predetermined shape by a foaming mold, on a cushion panel and covering it with a skin material. This seat pad is usually made of flexible polyurethane foam, but since polyurethane foam itself lacks flame retardancy, it is necessary to add various flame retardants such as chlorine-based, phosphorus-based, and bromine-based flame retardants. there were.

Further, since these seat pads are originally easily deformed and are used by directly mounting them on a metal spring, there is a drawback that a portion contacting with the frame or the metal spring is easily worn due to friction. Have Therefore, for the purpose of preventing damage due to such frictional wear and maintaining the shape, a non-woven fabric, a slab or the like is integrally foamed and embedded in a portion of the flexible polyurethane foam that comes into contact with the metal spring to form a rigid reinforcing layer. It has been used a lot.

[0004]

However, when the reinforcing layer is formed by integrally foaming a non-woven fabric, a slab, etc., there is a demerit that the flame retardant performance of the composite is significantly reduced. In order to prevent such a phenomenon and achieve the desired flame retardant performance, it is necessary to add a larger amount of the flame retardant for flexible polyurethane foam. This is not preferable because it causes an increase in cost and also has an adverse effect on moldability. Moreover,
Fogging (phenomenon of window glass of automobiles) and discoloration of skin materials, which have recently been regarded as a problem with interior parts for automobiles, are considered to be caused by hydrolysis and evaporation of these flame retardants. It is not preferable to increase the number because it impairs the aesthetics, comfort and comfort of the vehicle.

Therefore, it is an object of the present invention to provide an automobile seat pad in which the fogging of the window glass and the discoloration of the skin material due to the flame retardant are unlikely to occur, and moreover, the flame retardancy equal to or higher than the conventional one can be exhibited. is there.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to solve the above problems, and as a result, as a non-woven fabric for reinforcement that is embedded and integrated in a portion of a flexible polyurethane foam that comes into contact with a metal spring, a specific web. We have found that the intended purpose can be achieved by selectively using a thermal bond nonwoven fabric composed of a combination of fibers and a binder, and have completed the present invention.

That is, according to the present invention, in a soft polyurethane sheet pad placed on a cushion panel provided with a metal spring, a nonwoven fabric obtained by heat-bonding a polyester fiber web with low-melting polyester cotton is used. The subject is a seat pad for an automobile, which is integrally foam-molded at a portion of the soft polyurethane seat pad that comes into contact with a metal spring.

The thermal bond non-woven fabric referred to herein is a web made of polyester fiber (PET), acrylic fiber, nylon fiber (nylon 6, nylon 66), rayon fiber or the like, mixed with low melting point polyester cotton, and heated. By melting the low melting point polyester cotton, the web fibers are bonded to each other, especially at their intersections.

Usually, the material of the web used in combination with the low-melting point polyester cotton may be any material as long as it has a melting point higher than that of the low-melting point polyester cotton and can be strongly adhered thereto. Any of the fiber materials corresponds to this, but in the present invention, the most versatile polyester fiber (PET) is used for the web, and the low melting point polyester cotton is used for the adhesive (binder) thereof. ,
A nonwoven fabric formed by the thermal bond method is particularly selected and used.

Preferred polyester fiber webs for carrying out the present invention include webs made of PET fibers having a melting point of 255 to 260 ° C., a fiber length of 40 to 100 mm and a denier number of 3 to 15. Examples of the low-melting point polyester cotton preferably used as the binder include polyester cotton having a melting point of 100 to 110 ° C., a fiber length of 40 to 80 mm and a denier number of 3 to 10. However, it goes without saying that these characteristic values have no limit meaning and can be appropriately changed within the range publicly known and used in this field. Further, although this product is needle punched, such post-treatment is not always necessary.

As a method for integrally molding the above-mentioned thermal bond nonwoven fabric at a predetermined portion of a soft polyurethane sheet pad, a thermal bond nonwoven fabric cut to a predetermined size is detachably set on the inner surface of the upper mold of a foaming mold, Inject the undiluted solution for flexible polyurethane foam into the mold, close the upper mold,
The method of integrally foaming and hardening is particularly effective.

At this time, as the flame retardant added to the undiluted solution for the flexible polyurethane foam, those publicly known and used in this field can be used, for example, manufactured by Daihachi Chemical Industry Co., Ltd., trade names: CR505, CR530, CR504, C
Typical examples include R570, or Akzo Kashima Co., Ltd., trade names: PHIROLL VEF, PHIROLL 701S, PHIROLL 731, PHIROLL 751 and the like.

As described above, in the present invention, when a sheet pad is formed by integrally foam-molding a thermal bond nonwoven fabric made of polyester fiber and low-melting point polyester cotton at the portion of the flexible polyurethane foam which comes into contact with the metal spring, FM with an amount of flame retardant less than 20% of
It became clear for the first time that the flame-retardant performance specified in VSS 302 could be cleared.

Further, in the present invention, since the amount of the flame retardant added can be greatly reduced as described above, the problems of the prior art such as fogging of automobile window glass and discoloration of the skin material due to the flame retardant are effective. The cost can be reduced at the same time.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Table 1 shows an example of a thermal bond nonwoven fabric (a nonwoven fabric obtained by heat-sealing a polyester fiber web with a low-melting polyester cotton) according to the present invention. In the practice, first, the non-woven fabric is cut into a predetermined size and detachably set on the inner surface of the upper mold of the foaming mold through the fixing pin, and then the lower mold is filled with the undiluted solution for the flexible polyurethane foam containing the flame retardant. After pouring, the upper mold was closed, the foam was cured, and the polyurethane foam and the nonwoven fabric were integrally foam-molded to obtain the intended soft polyurethane sheet pad.

[0016]

[Table 1]

Table 2 shows the formulation of the stock solution for polyurethane foam used.

[Table 2]

Then, with respect to the obtained seat pad, F
A flame test was carried out according to the test method specified in MVSS 302 to evaluate the flame retardancy. The results are shown in Examples 1 to 2 in Table 3.
However, both are different in the basis weight of the non-woven fabric. As is clear from this, the combustion speed (mm / min) of the seat pad according to the present invention is substantially zero, and it can be said that it is nonflammable.

In Table 3, nonwoven fabrics obtained by immersing and impregnating various web fibers in a conventional binder (emulsion type SBR or emulsion type ethylene / vinyl chloride copolymer) (Comparative Examples 1 to 5). , And combustion test results measured on the obtained seat pad, which was molded in the same manner as in the above-mentioned example except that a thermal bond nonwoven fabric (comparative examples 6 to 7) made of a combination of acrylic fiber and low melting point polyester cotton was used. Is added. As is clear from Table 3, the seat pads (Examples 1 and 2) according to the constitution of the present invention can exhibit particularly excellent flame retardancy as a composite.

[0020]

[Table 3]

Table 4 uses the same thermal bond non-woven fabric as used in Example 1, but the amount of flame retardant in the stock solution for flexible polyurethane foam is a regular value (7.4 parts by weight per 100 parts by weight of polyol component). It is the result of testing the relationship between the added amount of the flame retardant and the flammability by molding the seat pad with a smaller amount than the above. According to this, even if the amount of the flame retardant added was reduced to 30% of the regular value (7.4 parts by weight), the combustion speed was substantially zero and it was nonflammable.
Further, even when this value was reduced to 10%, it was almost the same level as Comparative Examples 1 to 5 in which the conventional amount of the flame retardant in the flexible polyurethane foam stock solution was set to the regular amount (7.4 parts by weight) using the non-woven fabric. Flame retardant performance was obtained.

[0022]

[Table 4]

[0023]

As described above, according to the present invention,
Even if the amount of the flame retardant added to the flexible polyurethane foam is reduced to 20% or less of the conventional level, the flame retardance regulation (FMVSS 3
A seat pad for an automobile that fully satisfies 02) can be obtained. Also, by reducing the amount of flame retardant added, the fogging of window glass and the discoloration of the skin for seats, which were problems of the prior art, are greatly suppressed, and the appearance, comfort and comfort of the vehicle are improved, and the product cost is reduced. Down was achieved.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hideki Ogawa 1-17-18 Edobori, Nishi-ku, Osaka-shi, Osaka Prefecture Toyo Tire & Rubber Co., Ltd. (72) Masanobu Sakano 1-17-18 Edobori, Nishi-ku, Osaka-shi, Osaka No. Toyo Tire & Rubber Co., Ltd. (72) Inventor Mitsuaki Hayama 1-17-18 Edobori, Nishi-ku, Osaka City, Osaka Toyo Tire & Rubber Co., Ltd.

Claims (1)

[Claims] 1. A soft polyurethane sheet pad placed on a cushion panel provided with a metal spring, wherein a nonwoven fabric formed by heat-bonding a polyester fiber web with low-melting polyester cotton (thermal bond) is the soft polyurethane. An automotive seat pad, which is integrally foam-molded at a portion of the seat pad that comes into contact with a metal spring.