JPS61121903A - Manufacture of molded product - Google Patents

Abstract

PURPOSE:To prevent the inclusion of voids produced upon mixing of A component and B component of nylon reactive injection molding material by employing a reduced pressure buffer adaptor. CONSTITUTION:Respective components are led out of tanks 1, 2, reserving A component and B component of the material for nylon RIM and a constituent, in which the A and B components are mixed by using a mixer 4 such as static mixer, power mixer, collision mixer or the like, is deaerated by the reduced pressure buffer adaptor 7, thereafter, is poured into a preheated rubber mold, ceramics mold, metal mold or hybrid mold, which is provided in a vacuum chamber, and is heated heated further to produce the molded product.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is used as a material for nine mechanical parts for structural materials. Physically, it has excellent impact resistance and heat deformation temperature, and in terms of molding, it has an excellent appearance and a uniform shape. The present invention relates to a manufacturing method suitable for producing a wide variety of materials in small quantities with high quality and good productivity.

Conventional structure and its problems Conventionally, when performing reactive injection molding using nylon RIM materials, it is common practice to perform collision mixing inside a mixing head, and then spray this mixed liquid into a metal mold for molding. It was spot on. However, in this method, the liquid must be in a turbulent flow for collisional mixing, which has the disadvantage that voids are created and the voids cannot be completely removed. For this reason, variations in physical property values were observed, and in particular, variations of 10% or more were observed in impact values, which were 3 pages. Furthermore, in many manufacturing methods, pressure is applied after mixing in order to eliminate voids in this collision mixing, and for this reason, the molds had to be made of metal. For this reason, mold costs accounted for a large portion of manufacturing costs, and it was generally difficult to achieve cost benefits when considering productivity. In addition, this manufacturing method cannot be used especially for low-volume production of a wide variety of products.

Purpose of the Invention The purpose of the present invention is to solve the above-mentioned problems, to prevent the occurrence of voids in the molded product, thereby making it possible to obtain uniform physical property values, and to use rubber molds, ceramic molds, and metal molds. By doing so, the purpose is to provide a useful manufacturing method that can handle a wide variety of products in small quantities.

Components of the Invention In the material for nylon RIM, liquids A and B obtained by heating the raw materials A and B are mixed using either a static mixer or a power mixer. There are several vacuum buffer adapters from the mixed solution discharge nozzle to the vacuum chamber, and the mixed solution is guided into the vacuum chamber through the vacuum buffer adapters, which increase the degree of vacuum as the mixture passes through this liquid pool. Grind and preheat rubber molds.

Nylon RIM is produced by pouring it into a ceramic mold, metal mold, or hybrid mold and heating it further.
The method for manufacturing molded products using the material is for structural materials, mechanical parts materials, and has excellent impact resistance and thermal deformation temperature in terms of physical properties, and excellent appearance in terms of molding, and can be produced in a wide variety of products in small quantities. They discovered a completely new manufacturing method that could handle this problem.

This manufacturing method uses a vacuum buffer adapter, which is not used at all in conventional manufacturing methods such as vacuum casting and reactive injection molding.
This is a completely new improvement in that it can be completely defoamed using any mixing method, including power mixer or collision mixing, and there are no air bubbles in the molded product. ! , Attaching the Octopus Adapter From page 6, it is a completely versatile product that can be used for everything from large moldings using impingement mixing to small laboratory-level reactive injection molding machines using power mixers and even study mixers. New improvements have been made. In addition, by using a rubber mold or a ceramic mold, it has been improved to be able to handle a large variety of products in small quantities, which has a large cost advantage that could not be obtained with conventional manufacturing methods.

Description of examples Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

[Example 1] 1 is made of component A of nylon RIM material (Ube Industries ■),
Tank A contains the A component of UX-B, and tank B contains the B component (the B component of UX-B). 3 is pulp from which liquids A and B are poured out from their respective tanks. 4 is a static mixer for mixing two liquids. 5.8 is a pulp for adjusting the amount of the two liquid mixture. 7 is a vacuum buffer adapter;
6 is a Pal 6 pen knob for leaking the vacuum buffer adapter, and 9 is a vacuum hose for reducing pressure. 1° is
It is a vacuum chamber, and 11 is a gate opening of a mold 12. 13 is a vacuum valve.

Mass, A tank, B tank during the oil bath.

Immerse in a static mixer, etc., and soak in an oil bath for 90 minutes.
℃ and leave it for about 2 hours. Thereafter, after completely purging the insides of tanks A and B, liquids A and B, which are nylon RIM materials kept at 90° C. and liquefied, are poured into the respective tanks. After keeping warm for about 1 hour,
Pulp 3 is opened, poured into static mixer 4, and the two liquids are mixed. Open the pulp in step 6, pour these into the vacuum buffer adapter in step 7, and hold them at -76c for about 6 minutes.
After reducing the pressure to mHf and maintaining it, open the pulp in step 8, preheat it in a constant temperature bath at 160°C for about 3 hours, and purge the inside of the mold with N2. 1) Pour the mixed solution through the gate opening of the rubber mold. , fill the inside of the mold with the mixed liquid. this i
After being left in a constant temperature bath at 50C for about 6 minutes, the mold was removed.

Next, molding was performed in the same manner using a ceramic mold having the same shape as the rubber mold (Shinrai 7 Beno Kogyo (Yomei, Polar Ceramics R)).

I made a hybrid type as shown in Figure 2. Second
The figure is a cross-sectional view of a hybrid mold using rubber, ceramics, and metal as the mold material. 14 is made of ceramics, 16 is made of silicone rubber, and 17 is made of metal. The 16 lines that were cut showed the mating surfaces. Molding was carried out in the same manner using this hybrid mold.

None of the obtained molded products had any visible air bubbles, the molding cycle could be completed within 10 minutes, and the molds themselves were similar to rubber molds,
It was found that by using a ceramic mold, etc., it was possible to obtain an inexpensive product. Furthermore, the Izot impact value (with notch) is 13 to 15 (AI+-m/m),
H, D, and T also fall within the range of 180°C to 190°C,
Stable quality has been achieved.

[Example 2] Fig. 3 shows a case where stirring is performed using a power mixer. 18 is a stirrer, 19 is a stirring pie, 2
0 is a mixing chamber, 21 is a vacuum hose for reducing pressure, and 22 is a reduced pressure buffer adapter.

In the same manner as in Example 1, liquid A and liquid B were dissolved and mixed in the mixing chamber 2.
After the temperature reached 0, the mixture was stirred for 15 seconds using a stirrer. This was first degassed for 5 minutes at -26 cm Hfl using vacuum adapter D1, then degassed for 5 minutes at -76 cm Hf using D2, heated to 160°C, and placed in a rubber mold in a vacuum chamber prepared in advance. I poured it into The rubber mold filled with the liquid mixture was taken out from the chamber and left in a constant temperature bath at 150° C. for 10 minutes, then taken out and the molded product was demolded.

The resulting molded product reached fine and narrow parts of the molded product compared to the case under normal pressure, and no voids were observed. Also, since the mixture is poured in a vacuum and returned to normal pressure, the mixed liquid is pressurized by atmospheric pressure, resulting in dimensional accuracy of 0.
．． The result was that it could be kept within 1 to 0.5 units. The physical properties of this molded product were homogeneous with only variations within a factor of 5.

Effects of the invention From page 9 onwards, the present invention uses nylon RIM material, so
1 molding cycle compared to conventional urethane RIM materials
/15 to 1/2o, and the material properties are also better than that of urethane R.
Compared to IM, in particular, H, D, and T are improved by 1.5 to 2.0 times, and it is a rubber type.

Since a ceramic mold is used, the mold size is 1150 mm compared to conventional ones.
This method is effective as a manufacturing method that can be obtained at a low price as shown below and can be used to produce a wide variety of products in small quantities.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing an apparatus for mixing with a static mixer showing one embodiment of the present invention, having one vacuum buffer adapter, and injecting liquid into a rubber mold in a vacuum chamber, and Fig. 2 is a hybrid type. FIG. 3 is an explanatory view showing an apparatus for mixing two liquids with a power mixer, connecting two vacuum adapters in series, and injecting the liquid into a rubber mold in a vacuum chamber. 1...tank for component A, 2...tank for component B, 3...valve, 4...static mixer, 5...valve, 6... ... Leak valve of the vacuum buffer adapter, 7... Vacuum buffer adapter, 8... Vacuum hose, 9... Vacuum hose, 10... Vacuum chamber, 11... ...Gate entrance, 12...Type, 13
...Vacuum valve, 14...Ceramics, 1
6... Line indicating the mating surface, 16... Silicone rubber, 1. Metal. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2

Claims (3)

[Claims] (1) For nylon reactive injection molding materials, the A and B components obtained by heating the raw materials A and B are mixed using a static mixer or a power mixer, or one of these methods. The mixed solution obtained using the vacuum chamber is introduced into a vacuum chamber through a vacuum buffer adapter, and poured into a preheated rubber mold, ceramic mold, metal mold, or hybrid mold, and these are further heated to create a mold. A method for manufacturing molded products. (2) A vacuum buffer adapter has one or several liquid pools from the nozzle that discharges the mixed liquid to the vacuum chamber, and these liquid pools are under reduced pressure, and the mixed liquid passes through the liquid pools. 2. The method for manufacturing a molded article according to claim 1, wherein the degree of pressure reduction increases with each step. (3) The method for manufacturing a molded article according to claim 1, wherein the hybrid mold is a mold made of a plurality of materials such as rubber, ceramics, and metal.