JPS6096418A - Direct molding method of rubber and plastics - Google Patents

Abstract

PURPOSE:To contrive a reduction of a number of times of thermal histories and an improvement in molding yield, by a method wherein a resin or rubber loading material or others are molded while they are being supplied to a biaxial roller type mold as they are compounded, kneaded and extruded. CONSTITUTION:A resin or rubber loading material and others are put into a kneader 1 and loading and kneading are done at a predetermined temperature. Then a thing 3 to be kneaded is supplied continuously to a biaxial roll mold 4 by making a discharge screw 2 turn toward an extrusion side. Cooling and heating control of a main body 5 of rolls can be done by a rotary joint 6. The thing 3 to be kneaded is loaded between partition plates 8 set up on both sides by placing a cavity 7 between them. When the rolls are turned inwardly, cavities 7 engraved on the biaxial rolls, which are turned into a pair, are piled up completely, upon which the plasticized thing 3 to be kneaded is encroached for molding. Molded objects 9 are released continuously from a mold in a connecting state with a runner 10 engraved for a purpose of continuous mold release or burrs 11 through tension of an idle roll 12 and a conveyor 13.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a direct molding method for rubber and plastics, and more specifically, a method for directly molding rubber and plastics, and more specifically, a method for directly molding rubber and plastics, and more specifically, a method for directly molding rubber and plastics. A rubber that eliminates the process of forming rubber and plasticized molding materials into granules or pellets by continuously feeding the plasticized material through a blending and kneading process into a two-axis roller mold. Concerning direct molding of plastics.

Conventionally, the conventional method for molding rubber and plastics involves manufacturing a molding material through the steps of blending, mixing, granulation, or granulation, and then using an injection molding machine,
Transfer completed! l', the main method was to apply it to a direct pressure molding machine.

The advantage of such a method is that it can produce a large amount of molding material at one time, and can be used for molding products of a wide variety of products in small quantities as well as molded products of a large number of products.

However, the disadvantage of these methods is that the polymer is heated above its melting point and then heated again during molding.
It has been expected to reduce the number of heating cycles as much as possible for polymers that do not like heating cycles or molding materials that are prone to polymer breakage.

Next, even in the case of mass-produced items, the molding material must go through the process of manufacturing once, so it may absorb moisture during water cooling during granulation or granulation, or may absorb moisture during storage or undergo oxidation. Therefore, a process such as drying again is required during molding.
Here too, he did not have to worry about receiving heat.

Or, even if it is possible, molding materials with a formulation that causes adhesion or caking phenomena between particles during storage cannot be used for injection molding.
When used for hemostatic molding, it can cause extreme problems such as hopper drop, biting, short mold, mold separation, nozzle dripping, etc. riff
t, making it difficult to mold or unable to mold completely, so some methods use a sheet-shaped molding material and feed it to a molding machine.Moreover, injection molding, In the transfer molding method, molding is performed through the sprue and runner, which may result in gate unevenness and N-nicks due to the IIF-ness of the meat, and the molding yield excluding the sprue and runner is only 70 to 80%. It had many problems and drawbacks, such as:

Faced with such 1lff ljn fil, the inventor of the tree conducted intensive research to solve these four sets, and as a result, he focused on a method of immediately molding while mixing and kneading molding materials, which is currently in public use. As an application of the candy molding method, repeated research and improvement led to the completion of the wooden invention.

That is, the present invention is a method of mixing resin or rubber, filler, etc., and molding the mixture while extruding and supplying it to a twin-screw roller mold. The present invention provides a direct molding method in which blending, kneading, and molding are directly performed as one unit without any preparation.

In order to specifically explain the present invention, an example of the most preferable apparatus used in the wood invention will be described. FIG. 1 is a perspective view of the apparatus directly used in the molding method, and FIG.
FIG. 8 is a partially cutaway view of the cavity of the roll mold, and FIG. 8 is a plan view of the nI-type molded product upon receipt.

Mix resin or rubber with filler, etc. using a kneader for mixing (
1) and sufficiently mixed at a predetermined temperature, and when the mixing is completed, the discharge screw (2) is rotated to the extrusion side to continuously feed the mixed material (3) to the twin-roll mold (4).

The roll mold (4) can be attached to and removed from the roll body (5) via a key, and the roll body (51) can be cooled and heated by a rotary joint (6). The rotational speeds of the
: is inserted between the partition plates (8) set on both sides of the cavity (7), and when the roll rotates one turn inward, the cavity 17) carved into the two wheels so that they overlap completely, and this cavity (
7), the mixed wire material (31) is bitten into the molded product (9), and the molded product (9) is connected to a runner ridge or burr Qll carved for the purpose of a continuous hem μ, and an idler roller. t
Continuous HF type is formed by the tension of JJ and conveyor 03.

Depending on the molding conditions and the properties of the material, the closing pressure of the roll mold (4) is controlled by the hydraulic machine a4. #5 For materials with poor ε-type properties, periodically apply i from the hot molding agent nozzle aQ.
f: It is designed to spray rflA agent.

In order to specifically explain the wood invention in more detail, examples will be given below.

Example 1 100 parts of vinegar and ethylene copolymer (vinyl acetate ratio 45%) and 100 parts of the water absorbing agent Aqua Keep 10SH manufactured by Seitetsu Kagaku Co., Ltd. were mixed into a kneader FM-8RM-1 manufactured by Fuji Sangyo Co., Ltd. (with 100 IC, 60"C to 70"). After kneading for 5 minutes with
X 8mm thick fish cavity, pitch 20mm
, 42 pieces were taken, arranged in one row, the gap between the partition plates was set to 40 mm, the roll temperature was set to 40° C.±6° C., and molding was performed at a speed of 20 revolutions/minute. Molding ratio is 84
0 were completed, and 6 of them were unfilled. The molding yield after subtracting the weight of Paris and the weight of unfilled material is 98.5.
%Met. Put this thing in the water? When 1ffi was applied, the elongation rate in the length direction was 600%. That is, the volume is 2
The expansion rate was 1600%, and no separation and elution of the water absorbing agent was observed.

Comparative Example 1 100 parts of vinyl acetate ethylene copolymer (vinyl acetate ratio 46%) and 100 parts of Aqua Keep 10 S (manufactured by Hosuiyaku Tetsu Kagaku Co., Ltd.) were placed on a cooling roll under conditions that allowed them to be taken out in the form of a sheet.
A sheet with a thickness of 2 mm was made, and the ribs were cut into a 90 mm sheet using a cutter. Using an injection molding machine with a screw diameter of 80 mm, and using a lO cutting mold with the same cavity size as in Example 1, a l shot 2 minute cycle was applied. So, the cylinder temperature is 70
When molding was carried out at a temperature of ±1°C and a mold temperature of 40°C or less, 180 good products and 20 unfilled products were returned after 80 minutes of molding.
4 yield was 65%. When this molded product was immersed in water, the elongation rate in the length direction was 60096, the volume was 125009+f, and almost no elution of the water absorbing agent was observed; The shape of the swollen product tends to be deformed due to the formation of gate unevenness with high polymer content.

Control example 2 The sheet made in control example 1 is 4m84mX2mmX
When the pellets were made into cubes and molded, adhesion occurred between the particles, they fell into the hopper, and the biting was poor, resulting in almost no molding.

Comparative Example 8 When the diced pellets obtained in Comparative Example 2 were molded using charcoal, white carbon, polyethylene glycol, etc. as an n# type agent to prevent adhesion, the molding yield was 58%. The expansion coefficient in water is 800 in the length direction.
% and 2700% by volume, and the water absorbing agent was significantly eluted. The present invention consists of the embodiments described above, and the molding material does not undergo much heat history, significantly reduces the degree of oxidation, moisture absorption, deterioration, molecular scission, etc., and also directly blends the molding material. Because of the high molding speed and extremely high molding yield, the cost of the finished product is greatly reduced, the uniformity of the molded product is significantly improved, there is no gate unevenness, and the molded product is The quality is improved, and materials that cannot be subjected to injection molding or transfer molding can be molded with high yield and efficiency. In particular, soft materials, low melting point polymers, low temperature plasticized polymers, and granulation or It is extremely effective for molding materials that do not form granules or are difficult to form.

The preferred embodiments of the direct molding method for rubber and plastic according to the present invention have been described above, but it is possible to add various shapes to the method without departing from the spirit of the present invention, and these can also be incorporated into the present invention. #M#cIt is something that bends.

[Brief explanation of drawings]

Figure 1 shows the drum used for the direct molding method.
Figure 2 is a partial cross-sectional view of the cavity of the roll mold, Figure n is H-! Plan view 1 of the molded product when taken out, and the main symbols in the drawing are as follows. 1...n? , It's a knee, 2... Discharge screw, 2... Al1t thing, 4... Roll gold, 5... Roll body, G... Rotary joint, 7... Cavity, 8・・・Partition plate, 9...
・Molded product, lO...Runner, 11...Paris,
12... Idle roller, 18... Conveyor, 1
4...lll [EIll, 15...^ to the agent nozzle.

Claims (1)

[Claims] Mix resin or rubber with fillers and other ingredients and mix evenly with a 4-mix machine.
A direct molding method for rubber and plastics, in which molded metal is fed to two rotating rollers and molded while extruding in a mixed manner.