JPS60178012A - Manufacture of foam - Google Patents

Abstract

PURPOSE:To prevent the deterioration of working environment by mold releasing agent, omitting the coating of mold releasing agent and to prevent the inferiority of the surface of a foam by adsorbing the mold releasing sheet having been teflon treated, onto the bottom force for a foam. CONSTITUTION:The mold releasing sheet 11 having been teflon treated is attracted on the molding surface of a bottom force 2. Next, the stock solution 12 of foaming synthetic resin with separate bubbles, is poured on the mold releasing sheet 11. A top force 3 is placed onto the bottom force 2, and the foam 13 composed of separate bubbles is molded, while foaming and curing said resin. Next, at the state where the top force 3 is clamped, compressed air is injected into an air chamber 7, while operating the injection device 5 connected to the bottom force 2 of a foaming mold 1. The separate bubbles are broken by the pressure of this compressed air. Then, at the state where the top force 3 is opened, the injection device for compressed air is gradually operated, and the mold releasing sheet 11 and a foam 13 is easily released from the bottom force 2. The foam 13 is well separated from the mold releasing sheet 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a foam, and will be explained in detail by injecting a stock solution of closed-cell foamed synthetic resin into the lower mold of a foam mold, and then inserting the upper mold into the lower mold. The present invention relates to a method for producing a foam, which involves mold matching, foam curing to form a foam, and removing the foam from the foam mold.

Generally, a metal mold is often used as a foam mold, and when a foam is molded using this foam mold, a molding agent 11 is used to facilitate release of the foam. This mold release agent is in the form of a wax, such as paraffin wax or silicone wax, or in the form of a film, a solution of polyvinyl alcohol or acetyl cellulose is used.

However, when these mold release agents are used, the work of applying the mold release agent is complicated and the working environment is significantly deteriorated, and furthermore, the mold release agent adheres to the surface of the foam, causing surface roughness of the foam. This causes deterioration of physical properties, and also significantly inhibits adhesion when adhering a facing material to a molded foam. When the application amount of the broken mold release agent is small, or when the application is not uniform, it is extremely difficult to demold the foam, resulting in an increased number of defective products.

It is an object of the present invention to eliminate the need to apply a mold release agent to the lower mold of a foam mold every time molding, and to make it possible to remove the foam from the lower mold extremely easily, without deteriorating the working environment. The purpose is to provide a method for manufacturing a foam that improves efficiency and does not cause surface roughness or physical property deterioration of the molded foam, which will become clear from the detailed description below with reference to the drawings. Dew.

1 to 6 each schematically show an embodiment of the method for producing a foam according to the present invention, and a foam mold 1 used in the method of the present invention has a lower mold 2 and an upper mold 3. The lower mold 2 is formed into a vacuum mold.

A vacuum pump 4 for vacuum suction is connected to the lower mold 2, and a compressed air injection device 5 is further connected to the lower mold 2.

Reference numeral 2a in the figure is a through hole formed in the lower mold 2, through which the cavity 6 of the lower mold 2 and the air chamber 7 are formed in communication, and through the suction hole 4a and the injection hole 5a. The vacuum pump 4 and the injection device 5 are connected to the air chamber 7, respectively. Further, a clamp device 8 is provided at the upper end of the lower mold 2 .

As shown in FIG. 1, a mold release sheet 11 having mold releasability and airtightness is clamped onto the lower mold 2 by a clamp device 8.

The release sheet 11 may be fabric, non-woven fabric, etc. coated with Teflon to maintain airtightness, or Teflon formed into a sheet, or may be released from foam such as silicone. It is made of something that has a sexual nature.

After the mold release sheet 11 is clamped, the vacuum pump 4 is operated to adsorb the mold release sheet 11 onto the molding surface of the lower mold 2 as shown in FIG. The mold release sheet 11 may be press-molded to correspond to the shape of the molding surface of the lower mold 2, and the mold release sheet 11 may be arranged along the molding surface of the lower mold 2.

Next, as shown in the fsa diagram, the stock solution 12 of closed-cell foamed synthetic resin is injected onto the mold release sheet ll, and the upper mold 3 is replaced with the lower mold 2.
(Refer to FIG. 4 for the 1C type), a foamed synthetic resin stock solution is foamed and cured to form a foamed body 13 consisting of closed cells.

Next, with the upper mold 3 aligned, the injection device 5 connected to the lower mold 2 of the foaming mold 1 is operated to inject compressed air into the air chamber 7. The pressurized air in the air chamber 7 presses the airtight mold release sheet 11 in the direction of the upper mold 3 through the through hole 2a as shown in FIG.
3 to burst the closed cells of the foam 13. This injection of compressed air has a crushing effect on the foam 13, and the pressure of the compressed air is adjusted according to the size of the closed cells, etc., and by injecting compressed air several times, the foam is crushed. Proceed to foam breakage.

Next, as shown in FIG. 6, when the compressed air injection device 5 is gradually operated with the upper mold 3 in the open state, the mold release sheet 11 and the lower mold 2 are separated into closed cells. As is clear from the above, since they are not in an adhesive state, the mold release sheet 11 and the foam 13 are gradually released from the lower mold 2 with great ease, and at this time, the foam 13 of the release sheet 11 ( The joint with the tiller becomes gradually peeled off.

The foam 13 is obtained by peeling off the remaining bonded portion of the foam 13 and the release sheet 11 in a state in which the meat 11j I~rinshi 11 and the foam 13 are removed from the lower mold 2. Since the mold release sheet 11 is made of a material having mold releasability such as Teflon or silicone, it has good releasability from the foam 13 and there is no risk of damage to the foam 13.

The above is an example of the method for manufacturing a foam according to the present invention. According to this method, there is no need to apply a mold release agent to the lower mold of a foam mold, and the foam can be manufactured with great ease. The mold can be removed from the lower mold, and no mold release agent is applied, so there is no deterioration of the working environment. Also, the mold release agent does not adhere to the surface of the foam, causing surface roughness or physical property deterioration of the foam. It is possible to obtain a method for producing a foam that is highly economical and free from the risk of damage.

[Brief explanation of the drawing]

1 to 6 each schematically show an embodiment of the foam manufacturing method according to the present invention, and FIG. 1 is a cross-sectional view showing a state in which a release sheet is clamped to the lower die of a foam molding mold. Explanatory drawings, Figure 2 is a cross-sectional explanatory view showing a state in which the release sheet is vacuum-suctioned to the molding surface of the lower mold, and Figure 3 is a cross-sectional explanatory view showing a state in which a stock solution of closed-cell foamed synthetic resin is poured. , FIG. 4 is a cross-sectional explanatory diagram showing the state in which the foam has been molded, FIG. 5 is a cross-sectional explanatory diagram showing the state in which the compressed air injection device is operated to burst the closed cells of the foam, and FIG. FIG. 3 is an explanatory cross-sectional view showing a state in which the upper mold is opened and the foam and the release sheet are removed from the lower mold. In the figure, l...foaming mold, 2...lower mold, 3...upper mold, 4...vacuum pump, 5...injection device, 7...
Air chamber, 8... Clamp device, 11... Release sheet, 12... Stock solution of foamed synthetic resin, 13... Foamed body. Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] A compressed air injection device is connected to the lower mold of the foaming mold, and a ll1II type seam 1 having #-shaped property and airtightness is arranged along the molding surface in the lower mold of the foaming mold. C!・Pour the stock solution of closed-cell foamed synthetic resin into the second mold, match the upper mold to the lower mold, cure the foam, and mold the foam. Activate the compressed air injection device in the lower mold, inject compressed air from the bottom of the foam mold (1) to burst the closed cells of the foam, and then open the upper mold. In this state, the compressed air injection device was operated, and the foam was molded with the release sheet using compressed air. A method for manufacturing a foam with special features of 6 to 11.