JPH09154630A - Method of injecting compound latex material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the yield of a puff for makeup by reducing void and variation of foaming of a column-shaped foam rubber base material. SOLUTION: When a blended latex material 1 is injected via a discharge pipe 3 to a bottomed cylindrical mold 2, the injection is started from a position where the lower end 31 of the discharge pipe 3 is closed to the mold bottom face 21. After that, in association with rise of the level of the blended latex material 1 filled in the mold, the blended latex material 1 is injected while lifting the lower end 31 of the discharge pipe 3 so that the lower end 31 is not come into contact with the level of the material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casting method for injecting a compounded latex raw material into a mold so as not to cause air entrapment and foaming unevenness when a columnar foam rubber substrate for a cosmetic puff is produced. Regarding

[0002]

2. Description of the Related Art One of the methods for producing a cosmetic puff such as a powder foundation is to form a columnar foam rubber base material whose cross section is approximately equal to the size of the cosmetic puff surface and then slice the foam rubber base material. By cutting,
There is a manufacturing method that makes several cosmetic puffs from one foam rubber base material. The manufacturing method of such a cosmetic puff is
The outline is as follows. First, a raw material latex made of acrylonitrile-butadiene rubber (NBR), natural rubber (NR) or the like is blended with a metered compound such as a vulcanizing agent, an antioxidant and a dispersant. And, bubble stabilizer, pigment,
A gelling agent or the like is added, air for air is further mixed in, and mechanical agitation operation is performed to promote formation of fine bubbles. Next, the compounded latex raw material containing the fine bubbles is poured into a cylindrical mold to complete gelation at a predetermined temperature. Then, heat vulcanization is performed, and after washing, dehydration and drying, a columnar foam rubber substrate is produced. After that, the columnar foam rubber substrate is slice-cut (cut) into a predetermined thickness corresponding to a cosmetic puff, and after the final stage of polishing, powder removal, and inspection,
By packaging each one, a cosmetic puff product is completed.

Here, in the production of the cosmetic puff,
The method of injecting the compounded latex raw material into the cylindrical mold is conventionally
A method of casting the compounded latex raw material 1 from directly above the mold 2 (FIG. 3 (A)), a method of placing the mold 2 vertically and pouring the compounded latex raw material 1 by tying the inner surface of the mold ( 3 (b)), the method of casting the compounded latex raw material 1 by inclining the mold 2 obliquely to tie the inner surface of the mold 2 (FIG. 3 (c)) and the like have been adopted.

[0004]

However, the method of injecting the compounded latex raw material 1 into the cylindrical mold was unexpectedly difficult. If the injection method is poor, voids (cavities) are generated in the molded portion corresponding to the bottom portion 23 and the side surface 24 of the mold 2, which is a cause of defects. In the above-mentioned method, the air in the mold is hard to escape, and according to the method of ,, when the viscosity of the compounded latex raw material 1 is low, the generation of voids is relatively smaller than that of the method, but the raw material viscosity is If it is high, it will fall while entraining air, so it was easy to create voids. Further, when the method of and is adopted, the foaming unevenness is likely to occur in the product. When making a cosmetic puff with fine cells, it is necessary to increase the gelation speed of the compounded latex material 1,
In such a case, the portion at the beginning of pouring gels before the end of casting, and in many cases the product becomes defective due to layered unevenness.

The present invention solves the above problems and provides a method for casting a compounded latex raw material for reducing void defects and foaming irregularity defects of a columnar foam rubber substrate to improve the yield of cosmetic puffs. Characterize.

[0006]

In order to achieve the above object,
The gist of the present invention according to claim 1 is to inject the compounded latex raw material into a bottomed cylindrical mold from a discharge pipe.
Injecting is started from the position where the lower end of the discharge pipe is close to the bottom surface of the mold, and thereafter, as the liquid level of the compounded latex raw material filled in the mold rises, the lower end of the discharge pipe is pulled up from the liquid level while pulling up. A method for casting a compounded latex material is characterized by injecting a compounded latex material. Further, the casting method of the compounded latex raw material of the present invention according to claim 2 is the method of claim 1, wherein the lower end position of the discharge pipe at the start of injection and the pulling rate of the discharge pipe due to the rise of the liquid level of the compounded latex material are set. The feature is that automatic injection is performed so that it can be variably set.

According to the first aspect of the invention, the injection of the mixed latex raw material is started from the position where the lower end of the discharge pipe is brought close to the bottom surface of the mold, so that the air in the mold is not trapped. When the discharge tube is raised as the compounded latex material is filled in the mold, the compounded latex material is smoothly filled in the mold even if the injection speed is increased. Is reduced. Thus,
Filling of the compounded latex raw material is completed promptly. When the lower end position of the discharge pipe at the start of injection and the rising speed of the discharge pipe due to the filling of the blended latex raw material can be variably set as in the second aspect of the present invention, optimum injection according to the properties of the raw material becomes possible. Therefore, the amount of air entrained can be minimized. When these are automatically injected using a robot, not only productivity is improved, but also stable quality is maintained.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a method for casting a compounded latex raw material according to the present invention will be described in detail below. Figure 1
FIG. 2 is one mode of the method of casting the compounded latex raw material of the present invention, which is a step of molding a columnar foam rubber base material for a cosmetic puff, and FIG. 1 is a step of operating a mold, a discharge pipe and a discharge pipe. FIG. 2 is a schematic explanatory view of a mold robot, and FIG. 2 is a cross-sectional view showing a temporal change of injecting a compounded latex raw material into a cylindrical mold from a discharge pipe. The same reference numerals as those in FIG. 3 described above indicate the same or corresponding portions.

In the present invention, the compounded latex raw material 1 is injected into a cylindrical mold having a bottom to form a columnar foam rubber base material 7.
The compounding latex raw material 1 is formed here.
Is sent from the Oaks mixer (foamer) to the discharge pipe 3 via the pipe 4. Compounded latex raw material 1
Includes a latex such as NBR as a main raw material, a vulcanizing agent, a gelling agent, etc., and fine bubbles are included by the stirring operation of the Oaks mixer K. The discharge pipe 3 is attached to a work arm 51 of a known industrial robot 5. As an example, the variable sequence robot 5 is adopted.
The flow rate of the compounded latex raw material 1 from the discharge pipe 3 is determined in advance, and the lower end position of the discharge pipe 3 at the start of injection, the rising speed, and the molds are determined for a plurality of molds 2, 2, ... The order of filling 2 etc. is determined, and the robot 5
It has a manipulator 51 that advances sequentially according to this,
Moreover, it is possible to easily deal with the change of the setting information.

The casting method of the compounded latex raw material 1 is performed as follows. First, a plurality of bottomed cylindrical molds 2 are arranged, and a multi-cavity mold in which these are integrated by a stop frame 9 is placed on a set base 6 of the robot 5. Each vertically long mold 2 stands upright with the opening 22 facing upward. Then, by operating the robot 5, a series of operations is performed.

First, the discharge pipe 3 arranged in the vertical direction descends in the mold 2 and stops at a position where the lower end 31 approaches the mold bottom surface 21. Specifically, the mold bottom surface 2
The lower end 31 of the discharge pipe is set at a predetermined upper position within the range of 1 to 5 cm to 30 cm. 5 cm to 30 cm
The reason for this is that the proper position changes depending on the viscosity, specific gravity, etc. of the compounded latex raw material 1. Qualitatively, if the viscosity is low, from the mold bottom 21 to the discharge pipe lower end 3
The distance up to 1 is made closer, and conversely, for those with high viscosity, it is made a little more than the above distance. The cross-sectional area of the mold 2 is substantially the same as the size of the cosmetic puff, which is the final product, and has a circular shape, a rectangular shape, an oval shape, or the like. The diameter of the discharge pipe 3 is naturally smaller than the cross-sectional area of the mold 2, and the discharge pipe 3 has such a length that the lower end 31 can be brought close to the vicinity of the bottom surface of the mold.

Next, the valve 8 is opened and the injection of the mixed latex raw material 1 is started from the discharge pipe 3 (FIG. 2 (A)). Then, as the compounded latex raw material 1 is filled in the mold 2, the discharge pipe 3 is pulled up at a constant speed (Fig. 2 (b),
(C)). The rising speed of the liquid surface 11 increases in proportion to the discharge amount of the compounded latex raw material 1 per unit time, but the lower end 31 of the discharge pipe 3 is kept away from the liquid surface 11, and the distance between them is set to 5 cm to 30 cm. Keep pulling up.
Again, the lower end 31 depends on the properties of the compounded latex raw material 1.
~ The set position between the liquid surfaces is adjusted within the range of 5 cm to 30 cm. The range of about 5 cm to 15 cm is suitable for low viscosity, and the range of about 15 cm to 30 cm is suitable for high viscosity. If the viscosity of the raw material is low and the compounded latex raw material 1 is discharged to the liquid surface 11 with a head, the raw material will sneak into the liquid surface and void defects will easily occur. On the other hand, when the viscosity is high, the compounded latex raw material 1 in the discharge pipe is subject to a constant internal pressure, so that it tends to swirl, and if it is brought too close, this vortex will affect and it will be difficult to escape the entrapped air. This is because it is necessary to separate them a little. The viscosity of the compounded latex raw material 1 is difficult to measure because it is gelled or bubbles are crushed, and when it is replaced with a liquid specific gravity, one having a low viscosity is 0.25 or more, and one having a high viscosity is 0. It means less than 20.

Then, the latex material 1 to be blended into the mold
When the filling of the mold progresses and a predetermined amount is filled in the mold (Fig. 2
(D)), the valve 8 is closed and the injection is stopped. Thus,
The injection of the compounded latex raw material 1 into the one mold 2 is completed. At this point, the lower end 31 of the discharge pipe that has been in the mold until then comes to be located above the mold.

Next, the manipulator 51 moves horizontally based on the preset information, and the discharge pipe 3 is located right above the adjacent die 2.
Is set upright. Here, although it is the same for any of the molds 2, it is desirable that the discharge pipe 3 is arranged at the center position of the mold cross section.

Subsequently, similarly to the above, the discharge pipe 3 descends in the mold 2 and the injection of the blended latex raw material 1 is restarted from the point of approaching the mold bottom surface 21. Then, as the compounded latex raw material 1 is filled in the mold, the discharge pipe 3
The injection is continued while the pressure is being raised, and after the predetermined amount has been injected, the valve 8 is closed. Thus, the casting of the blended latex raw material 1 is repeated one after another to complete the injection of the blended latex raw material 1 into all of the multi-cavity molds integrated by the stop frame 9. Then, when the gelling is completed at a predetermined temperature, a molded product with no void defects and uneven foaming is obtained, and then heat vulcanization,
When washing, dehydration and drying are completed, the desired foam rubber substrate 7 is completed. The cosmetic puff as the final product is made by slicing and cutting the foam rubber base material 7, polishing, inspecting, etc., and packaging each piece.

By the way, when the specifications and the discharge amount of the compounded latex raw material 1 different from the present embodiment, the mold cross-sectional shape, the tube length, etc. are used, the lower end position of the discharge pipe 3 at the start of injection and the compounded latex raw material. The pulling speed of the discharge pipe 3 associated with the rise of the liquid level of No. 1 is readjusted. Further, the size of the discharge pipe 3, which is an end effector, is exchanged if necessary.

Compounded latex raw material 1 thus constructed
According to the casting method of 1, the injection of the mixed latex raw material 1 is started from the position where the lower end 31 of the discharge pipe is brought close to the mold bottom surface 21, so that the injection of the mixed latex raw material 1 seals the air in the mold. This reduces the number of void defects generated at the bottom and side surfaces, which are often found in the conventional method. Also, since it is not a method of pouring through the wall surface of the mold, there is no problem even if the flow rate of the compounded latex raw material 1 per unit time is increased, and gelation speed must be increased. Even the production of the rubber base material 7 can sufficiently cope with quality. The foaming unevenness due to the deviation of gelation of the compounded latex raw material 1 is eliminated. Further, the robot starts the injection from the position where the lower end 31 of the discharge pipe is close to the bottom face 21 of the mold, and pulls up the lower end 31 of the discharge pipe in a state of being separated from the liquid surface 11 as the liquid level of the compounded latex raw material 1 rises. Since it relies on automatic injection of No. 5, it contributes to maintaining stable quality of the foam rubber substrate 7 and labor saving. Although the accuracy is poor, this may depend on human power. In addition, since the robot 5 can variably set the lower end position of the discharge pipe 3 at the start of injection and the lifting speed of the discharge pipe 3 due to the rise of the liquid level of the mixed latex raw material 1, the mixed latex raw material 1 having various properties can be set. In addition, the foam rubber substrate 7 having various shapes can be manufactured without any trouble.

The present invention is not limited to those shown in the above-mentioned embodiment, but can be variously modified within the scope of the present invention depending on the purpose and application. The shapes and sizes of the mold 2, the discharge pipe 3 and the like are appropriately selected according to the application. The robot 5 may be a numerical control robot or the like. Foam rubber base 7
Can of course be used for applications other than cosmetic puffs.

[0019]

As described above, the casting method of the compounded latex raw material of the present invention is excellent in quality improvement since void defects and foaming irregularity defects are reduced in the foam rubber substrate to be molded, as compared with the conventional method. Exert the effect.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory diagram of a mold, a discharge pipe, and a casting robot that operates the discharge pipe according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a temporal change of injecting a compounded latex material into a cylindrical mold from a discharge pipe.

FIG. 3 is an explanatory sectional view of a conventional technique.

[Explanation of symbols]

 1 Compounded latex raw material 11 Liquid level 2 Mold 21 Bottom 3 Discharge pipe 31 Lower end

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical indication location B29L 31:48 (72) Inventor Yoshiaki Yano 680, Hongo, Ikeda-cho, Ibi-gun, Gifu Prefecture Seino Inoac (72) Inventor Terumi Ito, 680 Hongo, Ikeda-cho, Ibi-gun, Gifu Prefecture Stock company Seino Inoac

Claims (2)

[Claims] 1. When injecting a compounded latex raw material into a bottomed cylindrical mold from a discharge pipe, the injection is started from a position where the lower end of the discharge pipe is close to the bottom face of the mold, and then the mold is filled. A method for casting a compounded latex raw material, comprising injecting the compounded latex raw material while raising the liquid level of the compounded latex raw material while keeping the lower end of the discharge pipe separated from the liquid level. 2. The blended latex raw material according to claim 1, wherein automatic injection is performed by variably setting the lower end position of the discharge pipe at the start of injection and the pulling rate of the discharge pipe due to the rise of the liquid level of the blended latex raw material. Casting method.