JPH04220313A - Manufacture of polyurethane sheet pad - Google Patents

Abstract

PURPOSE:To provide the manufacture of a polyurethane sheet pad, which has excellent side-face holding properties while having soft feeling on the surface of a side section on sitting and in which there is no generation of creases, etc., in a skin material. CONSTITUTION:In the manufacture of a sheet pad consisting of a polyurethane foam obtained by foam-molding a polyurethane foaming stock solution into the surface mold of a foaming mold made up of a rear mold molding the rear side section of a foamed product and the surface mold molding a surface side section, a section corresponding to the side-section surface of the product after the foaming of the surface mold is spray-coated with the polyurethane foaming stock solution having hardness lower than polyurethane constituting the lower section of the side section of the product and the stock solution is foam-molded, and the polyurethane foaming stock solution having hardness lower than polyurethane organizing the lower section of the side section of the product is injected to a section corresponding to a seat section and the polyurethane foaming stock solution to a section corresponding to the lower section of the side section and foamed and integrated, thus acquiring the polyurethane sheet pad.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing polyurethane sheet pads for use in automobile seats.

0002

2. Description of the Related Art Generally, an automobile seat has a spring material set on a seat frame, and a seat pad material placed on top of the spring material, or a thick seat pad material is placed directly on the top of the seat frame, and the upper surface of the spring material is placed on top of the spring material. is covered by the trim cover assembly.

[0003] Seat pads used for seats in automobiles and the like are generally made of shaft felt, latex foam, polyurethane foam, etc., and at the same time provide a seated occupant with a soft feel on the seat surface. This gives the spring action and damping action as a cushion body.

[0004] In recent years, consideration has been given to the holding characteristics of a seat for an occupant, and there has been an increasing need for seat pads with different hardness, the side portions of which are harder than the seat pad. This sheet pad of different hardness is made by placing a mold 1 of a predetermined shape as shown in FIG. By injecting a first polyurethane raw material 4 and a second polyurethane raw material 5 having different hardness from those of 2, 2, and 3 into the mold 1, and then foaming the first polyurethane raw material 4 and the second polyurethane raw material 5. The sheet pad 6 of different hardness is formed to have a cross-sectional shape as shown in FIG.

The mold 1 has a partition 7 formed at the boundary between the parts where the first polyurethane raw material 4 and the second polyurethane raw material 5 are injected. Contamination is prevented.

However, in the above-mentioned method for manufacturing polyurethane sheet pads of different hardness, depending on the shape of the sheet pad, the partition provided in the mold is not useful, and two or more types of polyurethane raw materials may be mixed with each other, resulting in a decrease in the foaming rate. Also, due to the difference in foaming height, the interface between the two or more types of raw materials is disturbed, making it impossible to obtain a desired sheet pad.

[0007] As a method for manufacturing polyurethane sheet pads with different hardnesses that eliminates these drawbacks, expands the degree of freedom in arranging polyurethane raw materials of different hardnesses, and enhances the functionality and aesthetics of the sheet, a method of manufacturing polyurethane sheet pads with different hardnesses is proposed. At least one type of polyurethane raw material of multiple types is sprayed into the mold without mixing with each other to foam, and then other different types of polyurethane raw materials are injected into the mold and foamed. A method for manufacturing polyurethane sheet pads with different hardness (Japanese Patent Application Laid-Open No. 160241/1983) was developed. In this method, for example, a mold as shown in FIG. 3 is used to obtain polyurethane sheet pads of different hardness as shown in FIG. 4. Both sides of the polyurethane sheet pad 6' in FIG. 4 are made of the first polyurethane raw material 4 with high hardness, and the other parts are made of the second polyurethane raw material 5 with low hardness. When manufacturing the above polyurethane sheet pad 6', first,
The above first coating is applied to both sides of the mold 1' by spraying.
The polyurethane raw material 4 is sprayed and foamed, then the second polyurethane raw material 5 is injected into the mold 1' and foamed, and the mold 1' is further cured in a cure furnace,
Finally, the polyurethane sheet pad 6' of different hardness is removed from the mold 1'.

However, in such a polyurethane sheet pad, all the side portions have high hardness, so there is a problem that the seating feeling is impaired because there is no soft feeling when sitting. Furthermore, since all the side parts are highly hard, there is a drawback that when assembling the skin material, it does not fit well with the skin material, causing wrinkles and the like, resulting in poor finished quality.

[0009]

[Problems to be Solved by the Invention] The object of the present invention is to provide a method for manufacturing a polyurethane seat pad that has good side holding properties, has a soft feel on the side surface when seated, and does not cause wrinkles on the surface material. Our goal is to provide the following.

0010

[Means for Solving the Problems] The present invention involves injecting a polyurethane foam stock solution into the surface mold of a foaming mold, which consists of a back mold for molding the back side portion of a foamed product and a front mold for molding the front side portion. In the manufacturing method of a sheet pad made of polyurethane foam, a polyurethane foaming stock solution having a hardness lower than that of the polyurethane constituting the lower side part of the product is sprayed onto a portion corresponding to the surface of the side part of the product after surface foaming. After foam molding, a polyurethane foam stock solution with a lower hardness than the polyurethane that makes up the lower part of the side part of the product was injected into the part corresponding to the seat part, and a polyurethane foam stock solution was injected into the part corresponding to the lower part of the side part to integrate the foam. The present invention relates to a method for manufacturing a polyurethane sheet pad, characterized in that:

[0011] Furthermore, the present invention is capable of forming polyurethane foam by injecting and foam-molding a polyurethane foam stock solution into the surface mold of a foaming mold, which is composed of a back mold for molding the back side portion of a foamed product and a front mold for molding the front side portion. In the manufacturing method of the seat pad, polyurethane having a hardness lower than that of the polyurethane constituting the lower part of the side part of the product is added to both the part corresponding to the side part surface and the part corresponding to the seat part surface of the surface-type foamed product. After spraying a foaming solution and foaming, a polyurethane foaming solution with a hardness lower than that of the polyurethane constituting the lower part of the side part of the product is applied to the remaining part of the seat corresponding to the lower part of the seat and a part corresponding to the lower part of the side part of the product. This invention relates to a method for producing a polyurethane sheet pad characterized by injecting a polyurethane foam stock solution and foaming it integrally.

The present invention will be explained below with reference to the drawings.

FIG. 5 is a schematic cross-sectional view of a seat pad obtained by the method of claim 1 of the present invention, in which a side surface polyurethane foam 9 and a side lower polyurethane foam 1 are formed on both sides of the seat polyurethane foam 8, respectively.
It has 0.

FIG. 6 is a schematic cross-sectional view of a seat pad obtained by the method according to claim 2 of the present invention, and the seat polyurethane foam has a two-layer structure of a top surface portion 11 and a remaining bottom surface portion 12. The surface polyurethane foam of the side part and the polyurethane foam of the lower part of the side part are the same as those shown in FIG. In the seat pad of FIG. 6, it is preferable for the seat surface portion 11 and the side surface portions 9 to be made of the same polyurethane foaming solution, but they may be made of different materials.

In the present invention, the area to be spray coated as described above can be the side surface of the foamed product or the entire surface of the product, and the thickness is preferably 5 to 20 mm, and the hardness is A, which is the hardness of the spray coated area. , seat hardness B, and side hardness C, the following relationship is possible.

[0016]

[Example] Example 1 A foaming mold consisting of a back mold for molding the back side part of a foamed product and a front mold for molding the front part is sprayed onto the area corresponding to the side surface of a sheet pad product to form a foam with a core density of 0.
．． 06g/cm3, thickness 10mm, measurement range 5kgf
After applying a polyurethane foam stock solution that has a hardness of 0.5 kgf when measured with a push pull gauge, the seat is coated with a core density of 0.05 g/cm3 and a 25% compression hardness of 13.0.
g/314cm2, core density 0.07g/c on the side part
m3, hardness measured with the push pull gauge above is 2.5k
A polyurethane foam stock solution such as gf was injected and foamed and integrated to obtain sheet pads of different hardness made of polyurethane foams of three types of hardness.

[0017]

[Effects of the Invention] The sheet pad of different hardness obtained by the present invention has good side holding properties and has a soft side surface layer, so it has an extremely excellent sitting feeling. Furthermore, in the skin material assembly, wrinkles and the like do not occur when the side portions are rolled up, and the finished quality is improved.

[0018]

[Brief explanation of the drawing]

FIGS. 1 and 2 are schematic diagrams showing a conventional method for manufacturing polyurethane sheet pads of different hardness.

3-4 are schematic illustrations of a conventional manufacturing method showing an improvement over the method of FIGS. 1-2.

5-6 are schematic cross-sectional views of sheet pads obtained by the method of the present invention.

[Explanation of symbols]

1, 1' Molding mold 2, 3 Raw material injection nozzle 4, 4', 4", 5, 5' Polyurethane raw material 6, 6
' Different hardness polyurethane sheet pad 7 Partition 8 Seat polyurethane foam

Claims (2)

[Claims] Claim 1: A sheet pad made of polyurethane foam is produced by injecting a polyurethane foam stock solution into the surface mold of a foamed product, which is made up of a back mold for molding the back side portion and a front mold for molding the front side portion of the foamed product. In the manufacturing method, a polyurethane foam stock solution with a hardness lower than that of the polyurethane constituting the lower part of the side part of the product is sprayed onto the part corresponding to the surface of the side part of the surface-type foamed product, and then the seat part is foam-molded. A polyurethane sheet characterized by injecting a polyurethane foaming solution having a lower hardness than the polyurethane constituting the lower side portion of the product into a portion corresponding to the lower part of the side portion, and injecting a polyurethane foaming stock solution into the portion corresponding to the lower side portion to form an integrated foam. Method of manufacturing pads. [Claim 2] A sheet pad made of polyurethane foam is produced by injecting a polyurethane foam stock solution into the surface mold of a foamed product, which is made up of a back mold for molding the back side part and a front mold for molding the front side part. In the manufacturing method, a polyurethane foaming stock solution with a hardness lower than that of the polyurethane constituting the lower side part of the product is applied to both the part corresponding to the side part surface and the part corresponding to the seat part surface of the product after surface foaming. After spraying and foam molding, a polyurethane foam stock solution with a hardness lower than that of the polyurethane that makes up the lower part of the side part of the product is applied to the remaining lower part of the seat, and a polyurethane foam stock solution is applied to the part corresponding to the lower part of the side part. A method for manufacturing a polyurethane sheet pad characterized by integrally foaming it by injecting it.