JPS5914342B2 - Composite seat cushion material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Objective of the Invention) The present invention combines the cushioning properties of a cushioning material made of compression-molded plastic elastic foam fragments with a membrane layer to match the feeling of sitting, and to improve the physical properties necessary for seat design. This invention relates to a composite seat cushion material with a stress dispersion type structure that has been widely accepted.

(Prior art) In the conventional manufacturing of automobile seat cushions, furniture seat cushions, etc., the cushioning materials are generally foamed polyurethane foam, wrapper foam, etc.
Alternatively, compression-molded pieces of polyurethane foam fragments have been used, but each has advantages and disadvantages as a cushioning material.

5 Since these cushioning materials are made from a single raw material, they are limited to the unique properties of the raw material itself, and generally have certain characteristics as well as drawbacks as a cushioning material. be.

Automotive systems requiring especially dynamic physical properties10-
As a compression material, it is not always satisfactory. Therefore, it is not possible to use only a single molded cushioning material, and instead a steel spring and a rubber band are used together, or different types of cushioning materials are combined, and the cushioning material is molded by cutting out and waving. I came, but
The composite cushioning material according to the present invention has a special structure that disperses stress and improves the cushioning properties, and can be molded in one shot to achieve the required physical properties with only one molded cushion, while also reducing pollution. Plano is the cause
Since stick waste can be reused, it can be provided at low cost. There is also a method in which a plate-shaped flexible polyurethane foam material is set around the outer periphery and a flexible polyurethane foam stock solution is injected into the hollow part and foamed, but in order to inject the stock solution, the inner cavity of the outer skin made of the flexible polyurethane foam material is simply filled. It is simply filled with foamed resin, and as in the present invention,
Unlike the 90 model, which had a structure in which a slab block cushioning material of the desired hardness was placed inside at a desired position, and the outer periphery was surrounded by urethane foam fragments and compression molded, the structure was simple with delicate ergonomic properties. I couldn't get any kind of cushion.

(Structure of the Invention) The present invention is a compressed polyurethane foam fragment in which an elastic membrane layer of a desired hardness made of a resin such as a polyurethane elastomer is coated with an adhesive at a desired location inside 95 pieces of molded plastic elastic foam fragments. Hereinafter, an embodiment of the present invention will be described with reference to the drawings of FIGS. Form into foam fragments, sprinkle adhesive on it, and apply it evenly to prepare foam fragments 1.

As the adhesive, a polyurethane polymer which is reactively cured by moisture is suitable.

On the other hand, a soft foam body or stretchable fabric is coated or impregnated with a prepolymer for polyurethane elastomer and set to a required width suitable for the cushion material.

The prepolymer 1 is produced by reacting a mixture of polyether polyols and diols prepared by a conventional method with tolylene diisocyanate (T-80 or T-65) or the like. During this production, about 10 free isocyanate groups
(weight 70) or less, and unreacted tolylene diisocyanate is preferably 2.0 (weight %) or less. Next, when filling the foam fragments 1 into the mold 2 shown in FIG. 1, the foam pieces 1 are filled into a substantially flat surface using a urethane foam slap or stretchable fabric impregnated or coated with a polyurethane elastomer at required locations in the middle as a base material 3. The molded product 5 is heated and humidified by injecting water vapor through the pipe 4 provided at the bottom of the mold 2, and the inside of the molded product 5 is compressed into a desired shape that matches the seat cushion. A cured elastic membrane layer 6 as shown in FIG. 2 is formed.

The prepolymer used to impregnate soft foams or stretchable fabrics is generally MOCA (3,3/Zigroll 4).
, 4/di-amino-di-phenylmethane), etc., and hardens by reacting with polyamines, but it also forms a tough and highly elastic film layer 6 when reacted with water.

The base material to which the prepolymer is applied must be breathable, such as cloth or paper, but as shown in Figure 4, slab protection materials such as urethane foam wrapper stoms A, b, etc.
It may be applied to the surface of c or impregnated in a layer 1 to 2 thick.

The film layer 6 to be formed is not only one layer as shown in FIG. 2, but also a plurality of layers as shown in FIG. It is also possible to install it in the direction.

The most suitable embodiment for automobile seat cushion materials is shown in Fig. 4, in which A, b, and c are made with different specific gravity, hardness, weight, etc. in accordance with the required steresis loss curve. Or choose a slab of cushioning material of the same quality,
The surfaces of each of A, b, and c are coated with the elastomer prepolymer as necessary or impregnated to a desired thickness, and then placed in the desired position in the mold and subjected to a steam reaction, resulting in the formation of the elastomer prepolymer shown in Fig. 4. The cushion slab materials A, b, and c and the surrounding debris are simultaneously bonded to each other, and the urethane elastomer film layers 6'', 6''', and 6'''' are simultaneously formed, and the physical properties of the surrounding debris layers are A, When the physical properties of the foam bodies b and c are combined with the physical properties of the film layers 6'', 6'', and 6''2, the effects of the present invention are significantly demonstrated.

(Function of the invention) In the present invention, an elastic membrane layer made of polyurethane elastomer or the like is formed inside the molded product of plastic elastic foam fragments, so that the cushioning properties of the molded product have appropriate elasticity for seating, and can be adjusted. Become free.

The elastomer liquid that forms the membrane hardens upon contact with water vapor, and for example, the content of NCO groups is 3.2701 clay and 9,000 c.
When a prepolymer at p/25°C is cured with moisture in the air, the hardness (Shore A) is 30, 100% modulus is 5.0 Kf/d1, the tensile strength is 18.0 K9/(71. Elongation at break) 50070.Also, the NCO group content is 5
．． 8% viscosity 70,000 c. When 16 parts of the above MOCA is added to the prepolymer at p/25°C and cured, the hardness (Shore A) is 90,10070, and the modulus is 170 Kf.
/Crll tensile strength 400K9/CTI. It shows an elongation rate of 420 at break. The physical properties of molded article 5 are shown in FIG.

Curve 7 is for the structure shown in Figure 2, and curve 8 is for the structure shown in Figure 3, where the debris layer density is 0.050 and the membrane thickness is 1? It is molded in.

Curves 9 and 10 in FIG. 6 are hysteresis loss curves for a urethane foam foam mold density of 0.035 and a urethane foam fragment mold density of 0.05. (
Effects of the Invention) The present invention is a molded cushion that is compression-molded in one shot and has contradictory physical properties of a soft feel and a strong cushion. A cushion with elasticity has poor comfortability and is not suitable for obtaining delicate physical properties as a cushion material.However, the present invention combines the advantages of both, and a one-shot stress-dispersing composite cushion has been developed. It is easy to manufacture and therefore low cost.

Furthermore, in the case of a conventional cushion mold, a springless sheet could not be used unless it had a thickness of 100 m/m or more, but with the product of the present invention, a thickness of 50 m/m to 100 m/m is sufficiently satisfactory.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of the mold, Figs. 2 and 3 are cross-sectional views of the molded product, Fig. 4 is a cross-sectional view of a molded product according to an embodiment other than the above, and Figs. 5 and 6 are cross-sectional views of the molded product. The figure shows the hysteresis loss curve of the molded product. (Explanation of symbols of main parts), 1... Foam fragments (unreacted), 2... Molding mold, 3...
Base material, 5... Molded product, 6... Membrane layer.

Claims (1)

[Claims] 1 A polyurethane foam in which a membrane layer with desired hardness and elasticity is formed using a polyurethane elastomer membrane at a predetermined position inside a molded product of plastic elastic chip foam, and the outer periphery of the membrane layer is coated with a prepolymer adhesive. A composite seat cushion material made by surrounding crushed pieces and compression molding.