JPS62135328A - Production of bag shaped cushioning body - Google Patents

Abstract

PURPOSE:To prevent the generation of burr and the generation of a wall lacking part at the visor shaped side wall part, by a method wherein a foamable stock solution is supplied into a mold wherein a fluid leaking means is arranged to the contact part of an upper mold and a core and foamed to perform molding. CONSTITUTION:An upper mold 1 is fixed to a lower mold 3 in a freely openable and closable manner and a core 2 is fixed to one side part of the lower mold 3 in a freely openable and closable manner. A fluid leaking means 4 for leaking a part of the gas or foamable stock liquid in the molds is arranged to the contact part 5 of the upper mold 1 and the core 2. AS the fluid leaking means 4, vent holes (e.g., pores with a pore size of 2-10mm) or slits (e.g., fine grooves with a depth of 2-10mm and a width of 2-10mm) are arranged to the contact area of the upper mold and the core at a proper interval. Because a part of gas and the foamable stock liquid is leaked from the vent holes or the like, the leakage of the gas or the foamable stock liquid from a contact part 6 is suppressed to the min. degree and a problem caused by the formation of a burr is improved and a bag shaped cushion body, especially, the bag shaped back cushion body for molor a car seat can be prepared.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cushion body having a bag-shaped opening, and particularly to a method for manufacturing a bag-shaped back cushion body for an automobile seat.

BACKGROUND ART A part of a cushion body having a bag-shaped opening on the back side, for example, a bag-shaped back cushion body for an automobile seat, has a lower mold,
It is manufactured using a two-sided mold consisting of a middle mold and an upper mold. In other words, the method for manufacturing this type of bag-shaped cushion body is to set a middle mold in the molding chamber of the lower mold, close it with the upper mold, and then supply foam stock solution into the mold to perform foam molding. It has been used for a long time.

In this case, the foam does not fully reach the space between the middle and upper molds, that is, the bending side walls and the top bending wall of the cushion body, especially the space where the bending side walls are to be formed. Not only is there a problem in that lack of thickness is likely to be formed in the yielding wall, which impairs the aesthetic appearance and reduces strength, but it also has the disadvantage that it is not easy to control the amount of foam stock solution supplied into the mold. be.

Furthermore, in the conventional manufacturing method for bag-shaped cushion bodies, the foam stock solution leaks from the contact area between the lower mold and the upper mold located on the parting line and hardens, resulting in the formation of so-called "paris". There is a problem of being exposed. In other words, an extra process for removing the paris is required after demolding, and the removed pars must be disposed of by incineration, etc., which is not only disadvantageous in terms of cost, but also reduces the cost of removing the paris from the cushion body. Since correction is required, there is a problem in that the accuracy of mold matching between the abutting portions of the lower mold and the upper mold must be increased.

Problems to be Solved by the Invention An example of a method for avoiding the occurrence of the lack of thickness in the bowing wall is the method described in Japanese Patent Application Laid-open No. 59-31124. In addition to requiring additional steps, the above-mentioned problems caused by the formation of particles still remain.

In addition, as a method to solve the problem caused by the formation of bubbles, the upper mold corresponding to the eave wall part of the bag-shaped cushion body is provided with pores that allow the gas and foam stock solution in the mold to leak out. However, in this case, locally hardened protrusions are formed on the surface of the cushion body covering wall corresponding to the pores, and the protrusions are covered with a cover such as cloth. There is a disadvantage in that when covered, the covering cover locally rises and the appearance of the product is spoiled, making it necessary to remove it.

The present invention has been made to solve the above problems.

That is, in the present invention, a foam stock solution is supplied to the inner part of the mold, which is composed of a lower mold, a middle mold, and an upper mold, and a fluid leakage means is provided at the abutting portion of the upper mold and the middle mold, and the stock solution is poured into the mold. The present invention relates to a method of manufacturing a bag-shaped cushion body, which is characterized in that molding is carried out by foaming in a mold.

Hereinafter, the present invention will be explained based on the accompanying drawings.

FIG. 1 is a schematic longitudinal section showing an embodiment of a two-sided mold suitable for carrying out the method of the present invention. The middle mold (2) is fixed to the lower mold (3) via a hinge or the like so that it can be opened and closed.

A fluid leakage means (4) for leaking a part of the gas or foam stock solution in the mold is provided at the abutment part (5) between the upper mold (1) and the middle mold (2). .

Examples of the fluid leakage means (4) include bottom holes (for example, pores with a diameter of 2 to 1Q mm) and slits (for example, narrow grooves with a depth of 2 to 1Q mm and a width of 2 to 1Qmm). The contact areas of the upper mold and the middle mold are arranged at appropriate intervals.

When a foam stock solution is supplied into a king-type mold that is closed in the state shown in Fig. 1 and the stock solution is foamed within the mold, the stock solution is formed into a lower mold (3) and a middle mold (2). Foaming starts from the space between the middle mold (2) and the upper mold (1), and predetermined foam molding is performed by going around to the space between the middle mold (2) and the upper mold (1).

In this case, the contact part between the upper die (1) and the middle ffi (21) (
5) Some of the gas and foam stock solution inside the mold will leak out from the vent holes provided in the upper mold (
Since the leakage of gas and foam stock solution from the abutment part (6) between the mold 1) and the lower mold (3) is suppressed to a minimum, the problem caused by the formation of flakes described above is improved.

Further, the foaming fluid is arranged at the abutting portion (5) to prevent the foaming fluid from entering the space between the middle mold (2) and the upper mold (1), that is, the space corresponding to the bending wall of the bag-shaped cushion body. The provided fluid leakage means (4) act as a passageway for the foaming fluid, which facilitates its thorough distribution in the space. Therefore, the problem caused by the occurrence of a lack of thickness in the bending wall portion l of the bag-shaped cushion body is solved.

Furthermore, in the heating and foaming process, the means for fluid leakage (4)
The foaming state within the mold, especially the foaming state in the space between the middle mold (2) and the upper mold (1), can be checked by the amount of foaming fluid flowing out from the mold.

Furthermore, since the contact portion (5) including the hardened portion that has flowed out from the fluid leakage means (4) is located below the surface of the yielding wall of the bag-shaped cushion body, it is covered with a covering sheet such as cloth. hidden. Therefore, a step of cutting out the paris is not particularly necessary.

The foam stock solution used in the present invention is not particularly limited, and may be appropriately selected from foam raw materials that have been conventionally used in the production of cushion bodies, such as polyurethane foam stock solutions. .

A polyurethane foam stock solution is a composition containing a polyisocyanate, a polyol, a catalyst, a blowing agent, and the like.

Examples of polyisocyanates include 2,4-tolylene diisocyanate (1-165/35) lylene diisocyanate, 80/20 tolylene diisocyanate), 4,4'-cy'phenylmethane diisocyanate, polymethylene polyphenylinocyanate, N , N'-(4,4'-
Dimethyl-3,3'-diphenyl diisocyanate) uredione, 4,4,4"-trimethyl-3,3',3
Examples include ``-)lisocyanate 2,4.6-triphenyl cyanurate, hydrogenated MDI, and hydrogenated tolylene diisocyanate.

Examples of polyols include polyethylene oxide having two OHi molecules and a molecular weight of about 1,000 or more, and copolymers of polypropylene oxide and polyethylene oxide, among which trivalent or higher valent polyols include glycerin, trimethylol, etc. It is obtained by the reaction of propane, pentaerythritol, sorbitol, etc. with the alkylene oxide.It is also obtained by polymerizing unsaturated monomers such as acrylonitrile and styrene in the polyol, and copolymerizing it to a certain extent with the polyol. can also be used.

As a catalyst, trimethylamine, triethylamine,
Examples include tertiary amines such as N-methylmorpholine, N,N-dimethylethanolamine, and triethylenediamine, and organic tin compounds such as dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate, and stannous octoate. As blowing agents, water, dichlorodifluoromethane (R-12), trichloromonofluoromethane (R-11), methylene chloride, 1.1
Examples include halogenated alkanes such as -dichloro-1-fluoroethane.

According to the present invention, the production of bag-shaped cushion bodies has been solved by the occurrence of cracks at the abutment portion between the lower die and the upper die, which have been problems in the past, and the bending walls of the bag-shaped cushion body, among others. ,
Since the occurrence of a lack of thickness in the yielding side wall is suppressed or prevented, the bag-shaped cushion can be fully satisfied in terms of appearance, strength, etc. without requiring one additional process before closing the mold and after demolding. It is possible to produce a bag-like back cushion body for a body, especially a car seat.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing one embodiment of a two-sided mold used in carrying out the method of the present invention. (1) is an upper mold, (2) is a middle mold, (3) is a lower mold, (4) is a means for fluid leakage, and (5) is a contact portion between the upper mold and the middle mold. Figure 1

Claims (1)

[Claims] 1. A foam stock solution is supplied into a mold consisting of a lower mold, a middle mold, and an upper mold, and a fluid leakage means is provided at the abutting portion of the upper mold and the middle mold, and the foam stock solution is supplied into a mold. A method for producing a bag-shaped cushion body, characterized in that forming is carried out by foaming within the mold. 2. The method according to item 1, wherein the means for fluid leakage is a vent hole or a slit. 3. The method according to item 1, wherein the foam stock solution is a polyurethane foam stock solution. 4. The method according to item 1, wherein the bag-shaped cushion is a bag-shaped back cushion body for an automobile seat.