JP2001114917A - Foamed substrate for vehicle, its preparation method and sheet for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a foamed substrate for vehicles which substrate is light in weight while having a predetermined strength and/or has an improved recyclability. SOLUTION: This foamed substrate for vehicles comprises a polypropylene foamed material having a foaming magnification of 1.5-1.6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foamed substrate for a vehicle and a method for manufacturing the same, and more particularly, to a structure capable of securing strength and distortion.
The present invention relates to a lightweight foam substrate for a vehicle capable of improving recyclability, a method for manufacturing the same, and a vehicle seat.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 7, a vehicle seat 100 includes a skin material 110, a cushion material 120,
It is composed of a bottom plate 130 as a bottom plate. As a material for forming each member of the conventional vehicle seat 100, as an example, for the skin material 110, a polyvinyl chloride leather 111 and a base cloth 112 made of a material such as nylon, polyester, rayon, or cotton are laminated. A polyurethane foam was used for the cushioning material 120, and hard polypropylene was used for the bottom plate 130.

[0003]

[Problems to be Solved by the Invention] In recent years, due to the need for environmental protection of the earth and effective use of resources, interest in fuel efficiency and recyclability of vehicles has been increasing, and fuel efficiency has been improved. Light weight members and members that can be easily recycled are desired.

The urethane foam used as the cushioning material 120 of the conventional vehicle seat 100 has a tear or the like in the skin material 110, so that when rainwater or the like enters, it absorbs water to cause hydrolysis. There is a problem in that the portion that absorbs moisture is depressed, the cured portion deteriorates, and the like, and the seating feeling on the seat deteriorates.

[0005] The cushion material 120 due to the absorption of the above-mentioned moisture
As shown in FIG. 8, in order to prevent deterioration of
Waterproof film 113 between 10 and cushion material 120
However, there is a problem in that the number of parts increases, the manufacturing cost increases, and the number of steps increases.

Further, in a vehicle seat using polyvinyl chloride leather as a skin material, since the specific gravity of PVC (polyvinyl chloride) is heavy, the weight of the entire seat also becomes heavy.
There were also concerns about recyclability.

Further, for example, regarding the bottom plate of a vehicle seat, a hard material is used to maintain rigidity, and the weight increases accordingly, which is one of the factors that hinders reduction of the vehicle weight. .

SUMMARY OF THE INVENTION It is an object of the present invention to provide a lightweight foamed substrate having a predetermined strength and improved recyclability, and a method of manufacturing the foamed substrate for a vehicle. Another object of the present invention is to provide a vehicle seat having excellent water resistance and suitable for recycling.

[0009]

The above object is achieved by forming the foam substrate for a vehicle from a polypropylene foam having an expansion ratio of 1.5 to 1.6. in this way,
A foam substrate for a vehicle having an expansion ratio in the range of 1.5 to 1.6 is not only lightweight, but also sufficient in strength as a vehicle substrate.

[0010] In particular, when a foam substrate is provided with a cushion material on a bottom plate, and the cushion material is used as a bottom plate in a vehicle seat in which the cushion material is covered with a skin material, it is extremely suitable for weight reduction.

According to a third aspect of the present invention, a foamable material is filled between at least two molds and formed into a predetermined shape in a cavity of the mold. In the method of manufacturing a foam substrate for a vehicle made of a foamable material, after filling the mold with the foamable material, one of the at least two molds is moved in the cavity in the direction of increasing the thickness of the product. The problem is solved by foaming to a predetermined thickness. As described above, by moving the mold, the expansion ratio can be adjusted, and the thickness of the product can be adjusted.

Preferably, the initial cavity space width in the thickness direction of the mold is in the range of 1.5 to 2.5 mm, and the movement in the thickness increasing direction is in the range of 2.5 to 4.0 mm. Further, it is more preferable that the foamable material is polypropylene. As described above, by setting the initial space width in the mold in the range of 1.5 to 2.5 mm and the movement in the enlargement direction in the range of 2.5 to 4.0 mm, the expansion ratio is 1.5 to 2.5 mm.
The range can be set to 1.6, and the strength can be maintained while the weight is reduced.

According to the vehicle seat of the present invention, a cushion material is provided on a bottom plate, and the cushion material is covered with a skin material. The problem is solved by forming the skin material entirely from an olefin-based material.

[0014] As described above, the vehicle seat of the present invention is formed of the olefin-based resin for all of the skin material, the cushion material, and the bottom plate. Recycling is facilitated and recyclability can be improved.

Further, the above-mentioned materials forming the skin material, the cushion material and the bottom plate are the same as those of conventional materials, that is, polyvinyl chloride leather forming the skin material and polyurethane foam forming the cushion material. In addition, the vehicle seat of the present invention uses a foam for the bottom plate of the vehicle seat of the present invention, so that the weight of the entire vehicle seat is reduced, thereby improving the fuel efficiency of vehicles using the vehicle seat. To contribute.

Furthermore, since the polyethylene foam is used as the cushioning material, and the polyethylene foam is excellent in water resistance, for example, even when the skin material is damaged and rainwater or the like enters, the cushioning material is used. No settling or hardening, and a good seating feeling can be maintained.

Further, an olefin-based thermoplastic elastomer is used as a skin material, and since this olefin-based thermoplastic elastomer has excellent transferability, it is possible to form fine particles formed on an emboss plate for embossing the skin. The unevenness is clearly transferred, and it is possible to give a luxurious feeling to genuine leather.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. The members, arrangements, and the like described below do not limit the present invention, and can be variously modified within the scope of the present invention.

1 and 2 show an example using a foam substrate for a vehicle according to the present invention. The foam substrate for a vehicle according to the present invention can be used not only for the bottom plate of the vehicle seat shown in FIGS. 1 and 2 but also for a substrate of a vehicle interior component such as a pillar. This embodiment shows an example in which the present invention is used for a vehicle seat. FIG. 1 is a sectional view of the vehicle seat, and FIG. 2 is an enlarged view of a portion A in FIG.

In the present embodiment, the vehicle seat includes not only land-based motorcycles and scooters, but also snowmobiles and personal watercrafts, and further includes various vehicle seats such as three-wheeled buggies, straddle-type vehicles, and construction machine seats. Shall be included.

As shown in FIG. 1, the vehicle seat S comprises a skin material 10, a cushion material 20, and a bottom plate 30 as a bottom plate. The cushion material 20 is placed on the bottom plate 30, It is formed by covering the material 20 with the skin material 10.

First, specific materials for forming the skin material 10 will be described. The skin material 10 is, as shown in FIG.
It is formed of an olefin-based thermoplastic elastomer leather 11 and a base fabric 12 made of polypropylene fibers.
In this example, an olefin-based thermoplastic elastomer leather having a resin phase of polypropylene is used. The olefin-based thermoplastic elastomer leather has a low specific gravity among thermoplastic elastomers and is excellent in heat aging resistance, cold resistance, weather resistance, and electrical properties.

The base fabric 12 is formed from a knitted fabric using polypropylene yarns as polypropylene fibers. The base fabric 12 and the olefin-based thermoplastic elastomer leather 11 are laminated by a conventionally known method such as pressing, heating, and curing. The base cloth 12 is located between the skin material 10 and the cushion material 20, and when the skin material 10 and the cushion material 20 are displaced or the skin material is damaged, dust and rainwater enter the cushion material. It is to prevent.

The outer surface of the skin material 10 is given an arbitrary emboss (squeezing), and is formed in a leather touch. As the emboss, for example, a known press machine such as a lithographic press machine or a roll emboss machine, or an emboss machine can be used, and the uneven shape of the emboss plate is formed on the surface of the skin material by heat and pressure.

In this embodiment, as shown in FIG. 1, the skin material 10 is formed into a three-dimensional shape by sewing two skin materials 10 together. The two skin materials 10 are sewn at the position of the ridgeline 3 located between the seat surface 1 and the side surface 2. In addition, in order to form the skin material 10 into a three-dimensional shape, two skin materials are formed by sewing as described above,
Of course, other methods such as vacuum forming and welding may be adopted.

The end of the skin material 10 is fixed to the bottom plate 30. The end of the skin material 10 is fixed to the end of the bottom plate 30 by a staple needle 40 or the like,
If necessary, it is fixed by an adhesive.

The cushion member 20 is formed from a polyethylene foam. The polyethylene foam is obtained by foaming polyethylene pellets (beads) or powder mixed with a foaming agent. The cushion material 20 is formed into a sheet shape in which predetermined irregularities are formed on the seat surface. The cushion material 20 may be formed in advance and then bonded to the skin material with an adhesive or the like.
It is preferable to adopt a method of forming and integrating simultaneously with the skin material, since the time and effort for bonding can be omitted.

The bottom plate 30 is formed from a polypropylene foam. The polypropylene foam is obtained by foaming polypropylene pellets (beads) or powder mixed with a foaming agent. Bottom plate 30 of this example
Is formed from a polypropylene foam having an expansion ratio of 1.5 to 1.6.

Next, FIG. 3 to FIG.
The manufacturing method using the bottom plate as an example will be described with reference to FIG. Injection molding is used to manufacture the foam substrate for a vehicle of this example. Then, a foaming material (not shown) is filled between the at least two molds 51 and 52, and the cavity 5 of the molds 51 and 52 is filled.
3 is formed into a predetermined shape.

Then, as shown in FIG. 3, the molds 51 and 52 are moved from the opened state as shown in FIG.
Close 1,52. Then, as shown in FIG. 4, a polypropylene-based material is filled as a foamable material into the cavity 53 of the molds 51 and 52 in a closed state. After filling the foamable material, one of the at least two molds 51 and 52 is moved in the direction in which the thickness of the cavity 53 increases. Thereby, the cavity 53 expanded in the thickness direction
Within the range, the foam can be foamed to a predetermined thickness. At this time, the foamable material in contact with the mold has a dense cell structure, but has a large cell structure inside to secure a thickness. In the above example, an example using two molds 51 and 52 is shown. However, if the shape is complicated, not only the two molds but also other slide molds or the like may be used. Of course, a split mold or the like can be used.

In the present embodiment, the space width in the initial cavity of the mold shown in FIG. 4 is set in the range of 1.5 to 2.5 mm, and after filling the foamable material, the movement in the enlargement direction is performed as shown in FIG. The range is 2.5 to 4.0 mm. After the foaming is completed, the mold is opened as shown in FIG. 3 to take out the product.

Regarding the expansion ratio, in the present example, the thickness of the filling in the mold was 1.59 mm. And
The foaming ratio was 1.6 times, and the product thickness was 2.59. This is a test method determined by JIS (JIS-K
-7203). A test piece with a width of 20 mm is set at a distance between fulcrums of 60 mm, and a bending speed of 1.5 mm in the center
/ 60 min. The distortion at that time was measured. The result at this time is shown in FIG. As a result, the load was 2.41 kg at 10% strain. On the other hand, as a comparative example, the non-foamed one having a filling thickness of 2.3 mm had a thickness of 2.28 mm due to shrinkage and the like. When the same measurement was performed for this sample, the load was 2.34 kg. From this,
Even if the filling thickness is 1.59 mm, when foamed 1.6 times, it can withstand a load of 2.41 kg at 10% strain, which is comparable to 2.3 mm without foaming. In addition, in the case of one-time foaming with a filling thickness of 1.59 mm, the 10% strain was a load of 0.88 kg.

In this embodiment, a seat of a motorcycle or the like is taken as an example, and the explanation has been given based on a configuration in which a cushion material is placed on a bottom plate as a bottom plate. However, a seat having another configuration, for example, a construction machine seat Here, the cushion material 20 is placed on a frame as a bottom plate. Also in this case, the frame shall be formed from a polypropylene foam. In addition, the foamed substrate for a vehicle can be applied to vehicle interior parts such as pillars and console boxes.

When the weight reduction rate of the vehicle seat having the above configuration was measured, the weight reduction rate was 25 to 35%. As a specific example, the weight of a conventional vehicle seat (for a scooter) is 1100 to 150.
In contrast to the case of 0 g, when a similar vehicle seat was manufactured with the configuration of the present example, the weight was 800 to 1100 g.

[0035]

As described above, by forming the foamed substrate for a vehicle from a polypropylene foam having an expansion ratio of 1.5 to 1.6, not only is it lightweight, but also sufficient in strength as a vehicle substrate. It will be. Especially foam substrate,
If a cushion material is provided on the bottom plate and the cushion material is used as a bottom plate in a vehicle seat that is covered with a skin material, it is extremely suitable for weight reduction.

Further, according to the method of manufacturing a foamed substrate for a vehicle, the foamable material is filled between at least two molds and formed into a predetermined shape in a cavity of the mold. In the method for manufacturing a substrate, after filling the mold with the foamable material, one of the at least two molds is moved in the cavity in the direction of increasing the thickness of the product, and foamed to a predetermined thickness. Is solved by As described above, by moving the mold, the expansion ratio can be adjusted, and the thickness of the product can be adjusted. By setting the initial space width in the mold in the range of 1.5 to 2.5 mm and moving in the enlargement direction in the range of 2.5 to 4.0 mm,
The expansion ratio can be in the range of 1.5 to 1.6, and it is possible to maintain the strength while using a lightweight foam material.

As described above, in the vehicle seat of the present invention, since all of the skin material, the cushioning material, and the bottom plate are formed of the olefin-based resin, the time and effort required for separation can be reduced. Recycling is facilitated and recyclability can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a vehicle seat of the present invention.

FIG. 2 is an enlarged view of a portion A in FIG.

FIG. 3 is an explanatory view showing steps of a method for manufacturing a foam substrate for a vehicle.

FIG. 4 is an explanatory view showing steps of a method for manufacturing a foam substrate for a vehicle.

FIG. 5 is an explanatory view showing steps of a method for manufacturing a foamed substrate for a vehicle.

FIG. 6 is a table of measurement results.

FIG. 7 is a sectional view showing a conventional vehicle seat.

FIG. 8 is an enlarged view of a portion B in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Seat surface part 2 Side part 3 Ridge line 10 Skin material 11 Olefin thermoplastic elastomer leather 12 Base cloth 20 Cushion material 30 Bottom plate (bottom plate) 40 Staple needle S Vehicle seat 51,52 Mold 53 Cavity

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) B29L 31:58 B29L 31:58 F term (Reference) 4F074 AA24 CA23 DA02 DA35 4F100 AK03B AK03C AK04 AK07A AL09 AR00B AS00C AT00A BA03 BA07 BA10A BA10C DG01 DG11 DJ01A EC08 EC082 EC18 EC183 GB33 JB07 JB16 JL16 4F206 AA03 AA04 AA45 AC04 AD05 AD08 AD16 AD17 AH26 JA04 JE06 JE21 JL50 JW26 JW50

Claims (6)

[Claims] 1. A foam substrate for a vehicle, comprising a polypropylene foam having an expansion ratio of 1.5 to 1.6. 2. The foam for a vehicle according to claim 1, wherein the foam substrate is a bottom plate of a vehicle seat in which a cushion material is provided on a bottom plate, and the cushion material is covered with a skin material. substrate. 3. A method of manufacturing a foamed substrate for a vehicle, comprising a foamable material formed by filling a foamable material between at least two molds and molding the foamable material into a predetermined shape in a cavity of the mold.
A vehicle characterized in that, after filling the mold with the foamable material, one of the at least two molds is moved in the cavity in the direction in which the thickness of the product is enlarged, and foamed to a predetermined thickness. Of manufacturing a foam substrate for use. 4. The mold according to claim 1, wherein an initial cavity space width in a thickness direction of the mold is in a range of 1.5 to 2.5 mm, and a movement in a thickness increasing direction is in a range of 2.5 to 4.0 mm. Item 4. A method for producing a foam substrate for a vehicle according to Item 3. 5. The method according to claim 3, wherein the foamable material is polypropylene. 6. A vehicle seat in which a cushion material is provided on a bottom plate, and the cushion material is covered with a skin material, wherein the bottom plate, the cushion material, and the skin material are all formed of an olefin-based material. A vehicle seat characterized by the above-mentioned.