JP6055710B2 - Vent-up detection mechanism, vent-up prevention device, molded body manufacturing method, and molded body molding apparatus - Google Patents

Description

  The present invention relates to a vent-up prevention device, a method for producing a molded body using the vent-up prevention device, and a molding device for the molded body used in the method for producing the molded body.

  A molding method in which a vent is provided in a plasticizing cylinder of a molding device and volatile components are discharged from the vent to the outside of the molding machine in order to remove volatile components (gas components) such as residual monomers contained in the raw material resin before molding. It has been known. By using a molding device having a vent, it is possible to suppress deterioration of the resin derived from volatile components such as residual monomers, and further, moisture in the raw resin can be discharged and removed from the vent, so that preliminary drying of the raw resin can be omitted. , The molded body can be produced efficiently.

  However, in a molding apparatus having a vent, the phenomenon of venting up in which molten resin is discharged from the vent along with the discharge of the gas component has been a problem. When vent-up occurs, the vent is blocked by the molten resin, and the gas component cannot be discharged. As a method for detecting such a vent-up, for example, a method for optically detecting a vent-up resin has been reported. When vent-up is detected, control such as reducing the feed amount of the raw material resin in the plasticizing cylinder is performed to suppress this. Patent Document 1 discloses a vent-up detector comprising a contact sensor and a spool suspended below the contact sensor so as to move up and down at the vent portion of a kneading extruder (plasticizing cylinder). Has been. According to Patent Document 1, when the spool is pushed up by the rise of the molten resin from the vent and comes into contact with the contact sensor, vent up is detected by transmitting a contact signal.

  On the other hand, in Patent Document 2, a functional material such as a metal complex is dissolved in pressurized carbon dioxide such as supercritical carbon dioxide, and a pressure containing the functional material in the molten resin using a molding apparatus having a vent. A molding method for mixing carbon dioxide is disclosed. According to Patent Document 2, a plasticizing cylinder is provided with a plasticizing zone for plasticizing a thermoplastic resin into a molten resin, a high-pressure kneading zone for mixing pressurized carbon dioxide and the molten resin, and a vent. The decompression zones are provided in this order from the upstream side, and a seal mechanism capable of blocking the communication of each zone is provided at the boundary of each zone. The communication between the high-pressure kneading zone and the other zones is blocked by the sealing mechanism, and after the functional material is dispersed in the molten resin in a high-pressure state in the high-pressure kneading zone, the high-pressure kneading zone and the decompression zone are communicated. Thereby, the pressurized carbon dioxide is separated from the decompressed molten resin, and only the pressurized carbon dioxide gasified from the vent is exhausted. Patent Document 2 also discloses foam molding in which a portion of pressurized carbon dioxide remains in the resin and functions as a physical foaming agent.

JP-A-9-277351 International Publication No. 2012/120737

  In a molding method using a pressurized fluid such as pressurized carbon dioxide, vent-up is particularly problematic because the pressurized fluid acts as a plasticizer and the viscosity of the molten resin decreases. However, in the molding method using a pressurized fluid, the vicinity of the vent is filled with a pressurized fluid containing a volatile component (gas component) and a molten resin. Therefore, even if a glass window or the like that supports high pressure is provided in the vicinity of the vent, the glass window is contaminated with gas components and cannot maintain transparency, and it is difficult to detect the resin optically vented up from the glass window. . In the molding method using a pressurized fluid, since the inside of the plasticizing cylinder is molded in a pressurized state, in order to remove the resin that has blocked the vent due to the occurrence of vent-up, the inside of the plasticizing cylinder is temporarily removed. Need to be opened to the atmosphere. Therefore, vent-up has been an obstacle to stable continuous molding.

  Further, in the plasticizing cylinder disclosed in Patent Document 2, in which the sealing mechanism is provided, when the pressurized carbon dioxide is introduced, the sealing mechanism causes the high-pressure kneading zone, the plasticizing zone to which the raw material resin is supplied, and the vent. Communication with the decompression zone having is cut off. Thereby, the pressure between the zones and the flow of the molten resin are divided. Therefore, in the plasticizing cylinder disclosed in Patent Document 2, even if control such as reducing the feed amount of the raw material resin in the plasticizing cylinder is performed when vent-up is detected, a vent is provided from the high-pressure kneading zone. It is difficult to eradicate the vent-up because the amount of the molten resin moving to the decompression zone cannot be sufficiently reduced.

An object of the present invention is to provide a vent-up detection mechanism for detecting vent-up in a molding apparatus having a vent, and to provide a vent-up prevention device for preventing the vent from being blocked by molten resin that vents up. And a method for producing a molded body using the vent-up prevention device.

According to the first aspect of the present invention, it is used for foam molding using a pressurized fluid as a physical foaming agent, a vent is formed, and a thermoplastic resin is plasticized and melted into a molten resin inside the molten resin. body in the plasticizing cylinder, a vent-up detection mechanism for detecting the vent up of the molten resin, the vent-up detection mechanism, which is connected to the vent of the plasticizing cylinder for mixing the pressurized fluid and And a moving member which is a detection rod movably held in the main body, wherein one end of the detection rod is inserted into the vent, and a permanent magnet is provided at the other end. detect said moving member to move, the position displacement of the permanent magnet provided on the other end portion of the movable member without contact by the molten resin up to contact with the end portion of the one And a detecting portion is a magnetic sensor, the atmosphere around the moving member, the vent-up detection mechanism provided, wherein the a pressurized atmosphere that is pressurized to above atmospheric pressure by the pressurized fluid Is done.

According to a second aspect of the present invention, there is provided a vent-up prevention device according to the first aspect, wherein the vent-up detection mechanism is disposed in the main body, and the vent-up detection result from the vent-up detection mechanism is obtained. And a pressing mechanism that pushes back the vented molten resin into the plasticizing cylinder, the pressing mechanism includes a piston that pushes the molten resin back into the plasticizing cylinder, and when pushed back into the plasticizing cylinder, vent-up prevention device portion of the piston, characterized in Rukoto inserted into the vent is provided. The piston has a cylindrical portion that is partially inserted into the vent when the molten resin is pushed back into the plasticizing cylinder, and the moving member is movably held inside the cylindrical portion. May be.

According to a third aspect of the present invention, there is provided a method for producing a foam molded article, wherein a thermoplastic resin is plasticized and melted in a plasticizing cylinder in which a vent for discharging a gas component to the outside is formed. Mixing a pressurized fluid as a physical foaming agent with the molten resin, separating a part of the gasified pressurized fluid as a gas component from the molten resin , and separating the separated gas component and it is discharged from the vent to the outside of the plasticizing cylinder, with a vent-up detection mechanism, and detecting the vent up before Symbol molten resin by foaming molten resin to separate the gas components, and the desired the method comprising forming a shape, the vent-up detection mechanism, wherein the body connected to the vent of the plasticizing cylinder, a movable member is movably retained detected rod within said body, before One end of the detection rod is inserted into the vent, the other of said a moving member to which a permanent magnet is provided at an end portion, a positional displacement of the permanent magnet provided on the other end portion of the movable member non A detection unit that is a magnetic sensor that detects by contact, and the atmosphere around the moving member is a pressurized atmosphere pressurized to a pressure higher than atmospheric pressure by a pressurized fluid, and vents up the molten resin. When the molten resin to be vented contacts the one end portion of the moving member, the moving member moves, and the detecting portion is the other end portion of the moving member. There is provided a method for producing a foamed molded article, which comprises detecting the displacement of a permanent magnet provided in a non-contact manner.

Before SL pressurized fluid, pressurized nitrogen or may be pressurized carbon dioxide, by foaming the molten resin, may produce foamed molded article.

According to a fourth aspect of the present invention, there is provided a molding apparatus for producing a foam molded article, wherein a vent for discharging a gas component to the outside is formed, a screw is rotatably provided, and a thermoplastic resin is plasticized. A plasticizing cylinder that melts into a molten resin and mixes the molten resin with a pressurized fluid as a physical foaming agent , a pressurized fluid supply device that supplies the pressurized fluid to the plasticizing cylinder, and the vent The shaping | molding apparatus provided with the said vent-up detection mechanism of Claim 1 or 2 connected to is provided.
Moreover, the molding apparatus which manufactures the molded object of this aspect may be a molding apparatus provided with the vent-up prevention apparatus of the 2nd aspect connected to the said vent.

The plasticizing cylinder of this aspect includes a high-pressure kneading zone that mixes the molten resin and the pressurized fluid, and the vent that exhausts the pressurized fluid gasified from the molten resin mixed with the pressurized fluid. A pressure reducing zone formed, and further provided with a seal mechanism provided between the high pressure kneading zone and the pressure reducing zone and blocking communication between the high pressure kneading zone and the pressure reducing zone.

The vent-up detection mechanism of the present invention is attached to a plasticizing cylinder in which a vent for discharging a gas component to the outside is formed, and detects a molten resin that vents up . Further, the vent-up prevention device of the present invention detects the vent-up by the vent-up detection mechanism , and mechanically pushes the molten resin back into the plasticizing cylinder, so that the vent is blocked by the molten resin that vents up. Can be prevented or suppressed.

It is a schematic sectional drawing which shows the shaping | molding apparatus used for 1st Embodiment. It is a schematic sectional drawing of the vent-up prevention apparatus with which the shaping | molding apparatus shown in FIG. 1 is provided, Comprising: Fig.2 (a)-(f) is a figure explaining the drive of a ventup prevention apparatus. It is a flowchart which shows the manufacturing method of the molded object of 2nd Embodiment.

[First Embodiment]
The vent-up prevention device of this embodiment is used by being connected to a plasticizing cylinder of a thermoplastic resin molding device. As the plasticizing cylinder, a general-purpose plasticizing cylinder used in an injection molding machine, an extrusion molding machine, a foam injection molding machine, etc. can be used, but a vent for discharging gas components to the outside is formed. A vent-up prevention device in the form is connected to the vent. The vent-up prevention device of this embodiment may be a separate body from the plasticizing cylinder or may be formed integrally with the plasticizing cylinder.

  The vent-up prevention device according to the present embodiment includes a vent-up detection mechanism that detects that the molten resin leaks from the vent, that is, the molten resin vents up, and a molten resin that leaks from the vent (a molten resin that vents up). And a pressing mechanism for pushing back into the plasticizing cylinder. “Vent-up” is a phenomenon in which a thermoplastic resin (molten resin) melted together with a gas component leaks from a discharge port (vent) for discharging a gas component contained in the thermoplastic resin in a plasticizing cylinder of a molding apparatus. . In the present specification, the vent-up includes not only the phenomenon that the molten resin completely leaks out of the plasticizing cylinder but also the phenomenon that the molten resin leaks out of the plasticizing cylinder and enters the vent. . FIG. 2B shows a molten resin 70 a that leaks out from the plasticizing cylinder 210 and enters the vent 203 to vent up.

  Vent-up is a problem when the viscosity of the molten resin is low. For example, a resin that does not contain an inorganic filler, which is generally referred to as a non-reinforced resin, has a lower viscosity at the time of plasticizing and melting and tends to cause venting than a reinforced resin (a resin containing an inorganic filler). Also, in the case of foam molding or the like in which the molten resin contains a pressurized fluid such as pressurized carbon dioxide, the viscosity of the molten resin decreases because the pressurized fluid acts as a plasticizer. Therefore, the vent-up prevention device of the present embodiment functions particularly effectively in a molding method using non-reinforced resin or pressurized fluid.

  An arbitrary mechanism can be used as the vent-up detection mechanism of the present embodiment. For example, an optical detection mechanism that detects an optical change or a temperature detection mechanism that detects the temperature of a high-temperature molten resin can be used. A mechanical detection mechanism that mechanically detects the molten resin to be vented up is preferable because of high detection sensitivity. The mechanical detection mechanism is, for example, a moving member whose position is displaced by contact with resin that leaks from the vent (resin that vents up), and that detects the displacement of the moving member. A part. It is preferable that the moving member used for the mechanical detection mechanism is not affected by the temperature and viscosity of the molten resin with which it is in contact, and the ambient pressure, and moves smoothly when the molten resin comes into contact with it to cause positional displacement. In addition, if the pressure in the vent-up detection mechanism partially changes due to the displacement of the moving member, the detection sensitivity of the vent-up may be lowered. It is preferable that the pressure does not change. Therefore, it is preferable that the moving member is disposed so as not to interfere with surrounding components and is easily movable without load. Moreover, since it is difficult for the detection part (detection sensor) which detects the position displacement of a moving member to function stably under high pressure, it may be a mechanism which detects the position displacement of a moving member under atmospheric pressure in a non-contact manner. preferable. Further, the moving member may be disposed in the vent with a part thereof being inserted into the vent. Since the moving member is positioned in the vent, the molten resin that has entered the vent can be quickly detected, and the molten resin can be pushed back into the plasticizing cylinder at the initial stage of vent-up. Thus, it is possible to prevent the bent-up molten resin from solidifying and closing the vent.

  Any mechanism can be used as the pressing mechanism of the present embodiment as long as the molten resin leaking from the vent is mechanically pushed back into the plasticizing cylinder. For example, a mechanism that moves up and down like a piston is used. It may be used. The mechanism for driving the pressing mechanism is arbitrary, and a general-purpose drive mechanism such as an air cylinder, a cam, or a piezoelectric actuator can be used. In this embodiment, since the molten resin to be vented up is mechanically pushed back into the plasticizing cylinder, venting up can be reliably suppressed or prevented.

  The vent-up detection mechanism transmits a vent-up detection signal (detection result) when detecting the molten resin to be vented up, and the pressing mechanism starts an operation of pushing back the molten resin into the plasticizing cylinder based on the vent-up detection signal. Since the pressing mechanism is driven based on the vent-up detection signal (bent-up detection result), the present embodiment can efficiently suppress or prevent the vent-up. It is arbitrary how the pressing mechanism is driven based on the vent-up detection signal. For example, after the vent-up detection signal is transmitted, the pressing mechanism starts the molten resin push-back operation after a predetermined time has elapsed. Timer control may be performed.

  Below, the vent-up prevention apparatus 300 of this embodiment shown in FIG.1 and FIG.2 (a)-(f) is demonstrated. In the following description, the direction indicated by the arrow Y shown in FIGS. 2A to 2F is described as “upward”, and the direction indicated by the arrow Y ′ is described as “downward”.

  The vent-up prevention device 300 has a main body 30 connected by inserting an insertion portion 30 a into a vent 203 provided on the plasticizing cylinder 210 of the molding device 1000. A vent-up detection mechanism 310 that detects a leaking molten resin (resin to be vented up) 70a (see FIG. 2B) and a pressing mechanism 320 that pushes back the molten resin 70a leaking out of the vent into the plasticizing cylinder 210 are provided.

  The vent-up detection mechanism 310 is a mechanical detection mechanism, and is fixed to the main body 30 and the detection rod 31 (moving member) whose position is displaced (moved) in the vertical direction when the molten resin 70a leaking from the vent comes into contact. And a magnetic sensor 33 (detection unit) for detecting the displacement of the detection rod 31. One end 31a (downward end) of the detection rod 31 is inserted into the vent 203 and disposed at the center of the vent 203, and has a permanent magnet 32 at the other end (upward end). . When the molten resin 70a leaking from the vent contacts the tip 31a, the position of the detection rod 31 is displaced in the vertical direction, and the position of the permanent magnet 32 is also displaced in the vertical direction accordingly. The magnetic sensor 33 can detect a slight positional displacement of the permanent magnet 32 with high accuracy. The detection rod 31 does not require a seal material or the like around it, and is held in a cylindrical extrusion piston 35 described later without any interference without interfering with surrounding parts. Even if it is low, it can move up and down easily. Furthermore, the vent-up prevention device 300 includes a piston 34 that pushes the detection rod 31 downward on the detection rod 31.

  The pressing mechanism 320 includes a push-back piston 35 that pushes back the molten resin 70 a leaking from the vent into the plasticizing cylinder 210. The push-back piston 35 has a cylindrical portion 35b inserted into the vent 203 when the molten resin is pushed back into the plasticizing cylinder, and the detection rod 31 described above is inserted into the cylindrical portion 35b and moves in the vertical direction. Held possible. A groove (slit) 35c extending from the tip 35a is formed on the outer surface of the cylindrical portion 35b, and the gas component discharged from the vent 203 passes through the groove 35c and is discharged to the outside of the plasticizing cylinder 210. In the vent-up prevention device 300 of this embodiment, the push-back piston 35 and the above-described piston 34 are so-called air cylinder pistons that are driven in the vertical direction by compressed air. Therefore, the vent-up prevention device 300 is provided with a compressed air supply path and discharge path for driving these pistons, a large number of air seals, and electromagnetic valves, which are shown in FIGS. Omitted.

  Further, a discharge pipe 36 communicating with the outside is connected to the main body 30, and a pressure gauge 37 and a back pressure valve 38 are provided in the discharge pipe 36. The inside of the main body 30 is a closed system, and the gas component discharged from the vent 203 first moves into the main body 30 through the groove 35c formed in the cylindrical portion 35b of the pressing mechanism 320, and then the main body 30. It is discharged to the outside of the main body 30 through a discharge pipe 36 connected to. Therefore, the vent-up preventing device 300 can control the pressure inside the main body 30 to the set pressure of the back pressure valve 38, and further control the pressure near the vent 203 in the plasticizing cylinder 210 to the set pressure of the back pressure valve 38. it can. Thereby, the vent-up prevention device 300 can adjust the amount of gas components discharged from the molten resin while preventing the molten resin from being bent up.

  In particular, when the vent-up prevention device 300 is used for foam molding in which a pressurized fluid is contained as a physical foaming agent in the molten resin, excess physical foaming agent is discharged from the vent 203 before molding. By adjusting the pressure inside the main body 30, the pressure and concentration of the physical foaming agent in the molten resin can be stabilized. When the vent-up prevention device 300 is used for foam molding, the atmosphere in the vent-up prevention device 300, that is, the atmosphere around the vent-up detection mechanism and the pressing mechanism is the highest pressure reached when the physical foaming agent is contact-kneaded. In the following, it is preferable to control to atmospheric pressure or more, and it is particularly preferable to control to a pressure of 1 to 10 MPa. By setting the pressurized state to atmospheric pressure or higher, rapid volume expansion due to rapid decompression of the molten resin can be suppressed, which can contribute to suppression of vent-up.

  Next, a vent-up prevention method using the vent-up prevention device 300 of the present embodiment shown in FIGS.

  First, as shown in FIG. 2A, in the state where the molten resin 70 in the plasticizing cylinder is not vented up, the position of the tip 31a of the detection rod 31 in the vertical direction is the fixed position A. In the present embodiment, the tip 35a of the push-back piston 35 is located in the vent 203 even in the state shown in FIG. 2A where no vent-up occurs, but the gas component separated from the molten resin is the cylindrical portion 35b. It is always possible to discharge the vent 203 out of the groove 35c.

  As shown in FIG. 2B, when the molten resin 70 enters the vent 203, the bent-up molten resin 70a comes into contact with the tip 31a of the detection rod 31 and moves the tip 31a upward from the fixed position A. . Along with this, the permanent magnet 32 provided on the upper portion of the detection rod 31 also moves upward, and the magnetic sensor 33 detects the displacement of the permanent magnet 32 in a non-contact manner.

  When the magnetic sensor 33 detects that the tip 31a of the detection rod 31 has moved upward from the fixed position A by a predetermined distance, the vent-up detection mechanism 310 determines that the molten resin has been vented up, and the vent-up detection signal To send. When the vent-up detection signal is transmitted, the pressing mechanism 320 starts driving the push-back piston 35. In the present embodiment, an electromagnetic valve (not shown) that controls inflow and outflow of compressed air for driving the push-back piston 35 is opened and closed. Thereby, as shown in FIG.2 (c), the pushback piston 35 starts a downward movement. The push-back piston 35 moves downward until its tip 35a is positioned at the fixed position A, and pushes back the molten resin 70a that is vented up into the plasticizing cylinder 210.

  Thereafter, as shown in FIG. 2 (d), the piston 34 provided on the upper portion of the detection rod 31 is driven downward, and the tip 31 a of the detection rod 31 is pushed down to the fixed position A. After a downward pressure is applied to the detection rod 31 by the piston 34 for a predetermined time, the piston 34 is retracted upward as shown in FIG. Thereby, the front end 31a of the detection rod 31 is positioned at the fixed position A and is in an unloaded state. Thereafter, as shown in FIG. 2 (f), the push-back piston 35 moves upward, and the molten resin 70 in the plasticizing cylinder shown in FIG. 2 (a) returns to a state where it is not vented up (initial state).

  However, in the state shown in FIG. 2E, that is, in the state where the tip 31a of the detection rod 31 and the tip 35a of the push-back piston 35 are located at the fixed position A, the molten resin 70 enters the vent 203 again, and the vent When the up detection mechanism 310 transmits a vent-up detection signal, a signal for starting driving of the push-back piston 35 (a signal for moving the push-back piston 35 downward) is input again, so that the push-back piston 34 moves upward. It stays at the fixed position A without moving to, and continues to suppress or prevent the bent-up of the molten resin.

  As described above, the vent-up prevention device 300 of the present embodiment shown in FIG. 1 and FIGS. 2A to 2F has been described. However, the present embodiment is an example of a preferred embodiment of the present invention. It is not limited to. For example, in this embodiment, the groove 35c through which the gas component discharged from the vent 203 passes is formed on the outer surface of the cylindrical portion 35b of the push-back piston 35, but the main body into which the cylindrical portion 35b is inserted into the groove through which the gas component passes. 30 may be formed on the inner surface of the insertion portion 30a or may not be formed. When the groove through which the gas component passes is not formed, the gas component discharge speed decreases, but the gas component can be discharged from the gap (clearance) between the cylindrical portion 35b and the insertion portion 30a. In the present embodiment, the detection rod 31 (the moving member of the vent-up detection mechanism 310) is inserted into the cylindrical push-back piston 35 (the pressing mechanism 320). A structure in which a rod-like pressing mechanism is inserted into the moving member may be used. Further, in the present embodiment, as shown in FIG. 2C, after the push-back piston 35 is moved downward and the molten resin to be vented is pushed back into the plasticizing cylinder, as shown in FIG. Although the detection rod 31 is moved downward, the push-back piston 35 and the detection rod 31 may be moved downward simultaneously. Further, in this embodiment, the atmosphere around the vent-up detection mechanism 310 and the pressing mechanism 320 is controlled to be a pressurized state, but the back pressure valve 38 may be opened to set the surrounding atmosphere to atmospheric pressure. Further, the drive of the vent-up prevention device 300 may be controlled by a control device (not shown). In this case, when the vent-up detection mechanism 310 transmits a vent-up detection signal, the control device drives the pressing mechanism 320 and the like based on the vent-up detection signal. The vent-up prevention device 300 itself may include a control device, or a control device that controls a molding device to which the vent-up prevention device 300 is attached may control the vent-up prevention device 300.

[Second Embodiment]
In the present embodiment, a method for manufacturing a molded body using the above-described vent-up prevention device 300 will be described with reference to FIG. First, the thermoplastic resin is plasticized and melted into a molten resin in the plasticizing cylinder 210 connected to the vent 203 for discharging the gas component to the outside shown in FIG. 1 (step S1). As the plasticizing cylinder, a general-purpose plasticizing cylinder provided with heating means such as a band heater can be used in which a screw is rotatably provided.

  The thermoplastic resin used in the present embodiment is arbitrary, for example, polyamide such as polypropylene, polymethyl methacrylate, nylon, polycarbonate, amorphous polyolefin, polyether imide, polyethylene terephthalate, polyether ether ketone, ABS resin, polyphenylene sulfide, Thermoplastic resins such as polyamideimide, polylactic acid, and polycaprolactone can be used. Moreover, various inorganic fillers, such as glass fiber, talc, and carbon fiber, can also be kneaded. In general, a resin that does not contain an inorganic filler, which is referred to as a non-reinforced resin, has a lower viscosity at the time of plasticizing and melting and tends to cause venting than a reinforced resin (a resin containing an inorganic filler). Therefore, the molding method of the present embodiment that suppresses vent-up is effective as a molding method using a non-reinforced resin.

  Moreover, in this embodiment, the thermoplastic resin which has not performed preliminary drying can also be used. If the undried resin that has absorbed water is molded as it is, the appearance of the molded body is remarkably deteriorated. Therefore, in the conventional method for manufacturing a molded body, preliminary drying is performed in order to remove moisture from the thermoplastic resin as a raw material. For example, in the case of polycarbonate, preliminary drying is required at about 120 ° C. for about 8 hours. In the present embodiment, moisture in the molten resin can also be discharged and removed as a gas component from the vent, so that preliminary drying of the thermoplastic resin as a raw material becomes unnecessary, and a resin molded body can be produced efficiently at low cost.

  In this embodiment, a pressurized fluid such as pressurized nitrogen or pressurized carbon dioxide is introduced into the plasticizing cylinder to mix the molten resin and the pressurized carbon dioxide. In the present embodiment, foam molding is performed using a pressurized fluid as a physical foaming agent. The pressure and temperature at which the pressurized fluid is introduced into the plasticizing cylinder vary depending on the type of the pressurized fluid, and the conditions are arbitrary. However, since the density is high and stable, the liquid state or the supercritical state is preferable. When using pressurized nitrogen or pressurized carbon dioxide as the pressurized fluid, the pressure is preferably 3 to 25 MPa and the temperature is preferably 10 ° C to 100 ° C. If the pressure is 3 MPa or more, it can be stably introduced into the plasticizing cylinder 210, and if it is 25 MPa or less, the load on the apparatus is reduced. Moreover, if the temperature is in the range of 10 ° C. to 100 ° C., it is easy to control the pressurized fluid in the system. Note that the pressurized nitrogen and pressurized carbon dioxide used as the pressurized fluid in the present embodiment instantaneously become high temperature in the plasticizing cylinder 210 and the pressure also fluctuates. Therefore, the above-described state, temperature, and pressure of the pressurized fluid are values of the state, pressure, and temperature of the pressurized fluid in a stable state before being introduced into the pressurizing cylinder 210.

  The method for preparing the pressurized fluid is not particularly limited, and a conventionally known method can be used. For example, it can be prepared by pressurizing a pressurized fluid in a liquid state by a pressurizing means such as a syringe pump. In the present embodiment, the pressurized fluid concentration in the molten resin can be adjusted by discharging the pressurized fluid in the molten resin from the vent before molding the molten resin. Therefore, it is not necessary to strictly control the amount of pressurized fluid introduced at the stage of introduction into the plasticizing cylinder.

  Any method can be used for supplying the pressurized fluid to the plasticizing cylinder. For example, the pressurized fluid may be introduced intermittently into the plasticizing cylinder or may be introduced continuously. Further, the introduction of the pressurized fluid may be controlled by using a syringe pump capable of stable liquid feeding.

  Next, the gas component is separated from the molten resin and discharged from the vent to the outside of the plasticizing cylinder (step S2). The gas component is a low-molecular volatile component such as an unreacted monomer, a solvent, or moisture contained in the thermoplastic resin. When the thermoplastic resin is heated to become a plasticized and melted state, it becomes a gas component (gas), is separated from the molten resin, and is discharged from the vent to the outside of the plasticizing cylinder. By removing the gas component before the molding of the molten resin, it is possible to improve the resistance of the molded article to be produced. Further, since moisture in the molten resin can be discharged and removed from the vent, preliminary drying of the thermoplastic resin as a raw material becomes unnecessary, and a molded body can be manufactured at low cost and efficiently.

  In this embodiment, since the pressurized fluid is mixed with the molten resin, the excess pressurized fluid is also separated from the molten resin as a gas component and discharged from the vent 203 to the outside of the plasticizing cylinder 210. Moreover, it is preferable to control the atmosphere around the vent-up detection mechanism and the pressing mechanism to a pressurized state by the back pressure valve 38 of the vent-up prevention device 300. Thereby, the pressure and concentration of pressurized carbon dioxide in the molten resin can be stabilized. The atmosphere around the vent-up detection mechanism and the pressing mechanism is preferably controlled to a pressure state that is equal to or lower than the maximum pressure reached when the pressurized fluid (physical foaming agent) is contact-kneaded and is equal to or higher than atmospheric pressure. It is particularly preferable to control the pressure to -10 MPa.

  When the pressurized fluid is kneaded with the molten resin, the resin viscosity is lowered, and further, the pressure is reduced for exhaustion, so that the resin expands in volume and vent-up is likely to occur. As described above, when the molten resin vents up, the vent-up detection mechanism 310 of the vent-up prevention device 300 detects it (step S3) and transmits a vent-up detection signal. Based on the vent-up detection signal, the pressing mechanism 320 is driven to push back the molten resin 70a leaking from the vent into the plasticizing cylinder 210 (step S4). Thereby, it can prevent or suppress that the molten resin vented up obstruct | occludes a vent, and can perform continuous shaping | molding of molten resin smoothly.

  After the gas component is separated from the molten resin, the molten resin is injected or extruded from the tip of the plasticizing cylinder 210 and formed into a desired shape (step S5). In the present embodiment, a molten resin is injected and filled into a mold having a predetermined internal shape, and the molded resin (foamed molded body) in which foamed cells are formed by rapidly depressurizing the molten resin containing a physical foaming agent. .

  The manufacturing method of the molded body of the present embodiment shown in FIG. 3 has been described above. However, the present embodiment is an example of a preferred embodiment of the present invention, and the present invention is not limited to this. For example, in the present invention, a foamed molded body is manufactured by mixing a pressurized fluid with a molten resin, but a non-foamed molded body may be manufactured, or a pressurized fluid may not be mixed with the molten resin. In this embodiment, the back pressure valve 38 of the vent-up prevention device 300 controls the atmosphere around the vent-up detection mechanism and the pressing mechanism to a pressurized state, but the back pressure valve 38 is opened to make the atmosphere atmospheric pressure. Also good.

  Alternatively, the functional material may be dissolved in a pressurized fluid, introduced into the plasticizing cylinder together with the pressurized fluid, and mixed with the molten resin. Thereby, the molded object containing a functional material can be manufactured. The functional material is not particularly limited as long as it can be dissolved or dispersed in a pressurized fluid and can give a predetermined function to the obtained molded body. Examples of such functional materials include inorganic particles such as organometallic complexes and metal alkoxides or precursors thereof, inorganic fillers such as carbon fibers and glass fibers or modified compounds thereof, and alloys for promoting various resins. Examples include compatibilizers, surfactants, dyes, nanocarbons, antistatic agents, and flame retardant materials. The concentration of the functional material in the pressurized fluid can be appropriately selected in consideration of the type of the functional material to be used and the function of the target molded body, and is not particularly limited. Considering the aggregation of the functional material in the mixed high-pressure fluid, it is preferably not more than the saturation solubility. In particular, since the density of the pressurized fluid is drastically reduced in the plasticizing cylinder of the molding apparatus that becomes high in temperature, the concentration of the functional material is preferably about 1 to 50% of the saturation solubility.

  EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples.

[Example 1]
In this example, a non-reinforced nylon containing no inorganic filler (Amilan CM1017 manufactured by Toray) was used as the thermoplastic resin, and a foamed molded article was manufactured using pressurized nitrogen as a physical foaming agent. The non-reinforced nylon used in this example was pre-dried at about 100 ° C. for about 4 hours.

[Molding equipment]
A molding apparatus 1000 used in this embodiment shown in FIG. 1 will be described. The molding apparatus 1000 includes a kneading apparatus 200 having a plasticizing cylinder 210 and a vent-up prevention apparatus 300, a physical foaming agent supply apparatus 100 that supplies a physical foaming agent to the plasticizing cylinder 210, and a mold clamping provided with a mold 252. A unit 250 and a control device (not shown) for controlling the operation of the physical foaming agent supply device 100, the kneading device 200, and the mold clamping unit 250 are provided. Further, the kneading apparatus 200 is provided with a shut-off valve 26 that opens and closes by driving the air cylinder 27 at the nozzle tip 29, so that the inside of the plasticizing cylinder 210 can be maintained at a high pressure. A die is brought into close contact with the nozzle tip 29, and molten resin is injected and filled from the nozzle tip 29 into a cavity formed by the die.

  A kneading apparatus 200 shown in FIG. 1 includes a plasticizing cylinder 210, a screw 20 disposed in the plasticizing cylinder 210 so as to freely rotate and advance, an upstream side seal mechanism S1 disposed in the plasticizing cylinder 210, and a downstream side. The above-described vent-up prevention device 300 connected to the side seal mechanism S2 and the plasticizing cylinder 210 is provided. In this embodiment, in the plasticizing cylinder 210, the plasticized and melted molten resin flows from the right hand to the left hand in FIG. Therefore, in the plasticizing cylinder 210 of the present embodiment, the right hand in FIG. 1 is defined as “upstream” or “rear”, and the left hand is defined as “downstream” or “front”.

  Further, although not shown, at the rear end portion on the upstream side of the plasticizing cylinder 210, a rotation driving means such as a rotary motor for rotating the screw 20, a ball screw for moving the screw 20 forward and backward, a motor for driving the same, and the like Is connected to the moving means. The kneading apparatus 200 of the present embodiment, like the configuration of a conventionally known kneading apparatus, causes the molten resin to move forward (when the screw 20 is rotated counterclockwise when viewed from the rear side of the plasticizing cylinder 210 ( It is configured to perform forward rotation sent to the nozzle part side) and reverse rotation when rotated clockwise.

  On the upper side surface of the plasticizing cylinder 210, in order from the upstream side, a resin supply port 201 for supplying a thermoplastic resin to the plasticizing cylinder 210, and an introduction port 202 for introducing a physical foaming agent into the plasticizing cylinder 210. , And a vent 203 for exhausting the gasified physical foaming agent from the plasticizing cylinder 210 is formed. A resin supply hopper 211 and a physical foaming agent introduction valve 212 are disposed in the resin supply port 201 and the introduction port 202, respectively, and a vent-up prevention device 300 is connected to the vent 203. Yes. The introduction valve 212 is connected to the physical foaming agent supply device 100 provided outside the kneading device 200.

  A band heater (not shown) is disposed on the outer wall surface of the plasticizing cylinder 210, whereby the plasticizing cylinder 210 is heated to plasticize the thermoplastic resin. Further, a sensor (not shown) for monitoring pressure and temperature is provided at a position facing the inlet 202 on the lower side surface of the plasticizing cylinder 210 and a position facing the vent 203, respectively.

  In the kneading apparatus 200 having such a structure, the thermoplastic resin is supplied from the resin supply port 201 into the plasticizing cylinder 210, the thermoplastic resin is plasticized by the band heater to become a molten resin, and the screw 20 rotates in the forward direction. Sent downstream. The molten resin sent to the vicinity of the inlet 202 is contact-kneaded with the introduced physical foaming agent under high pressure. Next, gasification is achieved by adjusting the pressure of the atmosphere of the molten resin to lower the internal pressure of the molten resin contact-kneaded with the physical foaming agent below the maximum pressure reached when the physical foaming agent is contact-kneaded. A part of the physical foaming agent thus separated is separated from the molten resin, and the gasified physical foaming agent is exhausted from the vent 203. The molten resin sent further forward is pushed out to the tip of the screw 20, and the pressure of the molten resin becomes a reaction force against the screw 20, and the screw 20 moves backward by the reaction force to perform measurement. As a result, in the plasticizing cylinder 210, in order from the upstream side, the plasticizing zone 21 that plasticizes the thermoplastic resin into a molten resin, the molten resin and the physical foaming agent introduced from the inlet 202 are brought into contact under high pressure. A high pressure kneading zone 22 for kneading and a pressure reducing zone 23 for exhausting the physical foaming agent partially separated from the molten resin from the vent 203 are formed by lowering the internal pressure of the molten resin kneaded with the physical foaming agent. In order to efficiently perform the kneading of the molten resin and the physical foaming agent, a plurality of inlets 202 and vents 203 are provided in the plasticizing cylinder 210, and the high-pressure kneading zone 22 and the decompression zone 23 are provided in the plasticizing cylinder 210. A plurality of each may be formed. In this case, a plurality of vent-up prevention devices 300 may be connected to the plurality of vents 203, respectively.

  As shown in FIG. 1, an upstream side seal mechanism S <b> 1 that temporarily blocks communication between the plasticizing zone 21, the high-pressure kneading zone 22, and the decompression zone 23, respectively. In addition, a downstream seal mechanism S2 is provided. Thus, for example, when the physical foaming agent is introduced into the high-pressure kneading zone 22, the upstream side and the downstream side of the high-pressure kneading zone 22 are mechanically sealed, and the zones 21 and 23 adjacent to the high-pressure kneading zone 22 are reliably Can be cut off. As a result, the pressure in the high-pressure kneading zone 22 is maintained at a high pressure, so that the physical foaming agent can effectively penetrate into the molten resin. As the upstream side seal mechanism S1 and the downstream side seal mechanism S2, various types can be used as long as they block the communication between the zones 21, 22, and 23. However, the communication between these zones depends on the rotational state of the screw 20. In this embodiment, the upstream side seal mechanism S1 and the downstream side seal mechanism S2 disclosed in Patent Document 2 (International Publication No. 2012/120637) are used. The upstream-side seal mechanism S1 and the downstream-side seal mechanism S2 can block the communication between the zones 21, 22, and 23 by the reverse rotation of the screw 20, and the screw 20 can be rotated forward, stopped, or reversely rotated. The zones 21, 22, and 23 can be communicated with each other by decreasing the number.

  The physical foaming agent supply device 100 includes three nitrogen cylinders 10 having a pressure of 14 MPa connected in parallel, and the plastic foaming agent supply device 100 is connected to a pressure gauge 11, a pressure gauge 12, a pressure gauge 13, a back pressure valve 14, and a pressure gauge 15. It is connected to the physical foaming agent introduction valve 212 of the control cylinder 210.

[Manufacture of molded products]
A foamed molded article was manufactured using the molding apparatus 1000 shown in FIG. 1 described above. First, the discharge valve of the nitrogen cylinder 10 of the physical foaming agent supply device was opened, and the system up to the introduction valve 212 for introducing the physical foaming agent into the plasticizing cylinder 210 was pressurized. At this time, first, the pressure of nitrogen is adjusted by the pressure reducing valve 11 so that the display of the pressure gauge 12 becomes 9 MPa, and further, the nitrogen pressure is adjusted by the back pressure valve 14 so that the display of the pressure gauge 13 becomes 8.5 MPa. It was adjusted.

  On the other hand, in the kneading apparatus 200, the thermoplastic resin is supplied from the resin supply hopper 211, the plasticizing zone 21 is heated by a band heater (not shown) provided on the outer wall surface of the plasticizing zone 21, and the screw 20 is adjusted correctly. Rotated. Thus, the thermoplastic resin was heated and kneaded to obtain a molten resin. In this example, the plasticizing zone 21 of the plasticizing cylinder 210 was heated so that the temperature of the molten resin was 200 to 220 ° C.

  The molten resin was caused to flow from the plasticizing zone 21 to the high-pressure kneading zone 22 by positively rotating the screw 20 at a rotation speed of 100 rpm. Next, after the rotation of the screw 20 is temporarily stopped in the middle of the molten resin plasticizing measurement, the upstream seal mechanism S1 and the downstream seal mechanism are rotated by rotating the screw 20 reversely for 1 second (the number of revolutions: 50 rpm). The communication between the high-pressure kneading zone 22, the decompression zone 23, and the plasticizing zone 21 was blocked by S2. Further, the reverse rotation was continued for 5 seconds at a low speed of 10 rpm, while the introduction valve 212 was opened for 2 seconds, and pressurized nitrogen was introduced into the plasticizing cylinder 210. The monitoring pressure inside the plasticizing cylinder 21 by a pressure sensor (not shown) in the high-pressure kneading zone 22 when pressurized nitrogen was introduced was a maximum of 6 MPa. In this embodiment, before the molten resin is molded, excess nitrogen is separated and discharged from the molten resin, so that the amount introduced into the plasticizing cylinder 210 does not need to be strictly controlled. Therefore, precise control of the amount of pressurized nitrogen introduced into the plasticizing cylinder 210 was not performed, and an excessive amount was introduced into the plasticizing cylinder 210.

  After the physical foaming agent introduced into the high-pressure kneading zone 22 was dispersed in the molten resin at a high pressure in the high-pressure kneading zone 22, the screw 20 was returned to the normal rotation, and the molten resin was caused to flow into the decompression zone 23.

  In the vent-up prevention device 300 attached to the vent 203 in the decompression zone 23, the back pressure valve 38 was set to 4 MPa. As a result, the atmosphere around the vent-up detection mechanism 310 and the pressing mechanism 320 was set to a pressurized state of 4 MPa. The monitoring pressure by a pressure sensor (not shown) in the decompression zone 23 in the plasticizing cylinder 210 was always 4 MPa.

  The pressure of the molten resin and the physical foaming agent that flowed into the decompression zone 23 decreased to the set pressure of the decompression zone, 4 MPa. Thus, excess physical foaming agent (nitrogen) was gasified and separated from the molten resin, and then discharged to the outside of the molding apparatus 1000 through the vent 203 of the plasticizing cylinder 210 and the discharge pipe 36 of the vent-up prevention apparatus 300. .

  In the vent 203 of the decompression zone 23, when venting of the molten resin occurs along with the discharge of the gas component, the vent-up detection mechanism 310 of the vent-up prevention device 300 detects it and transmits a vent-up detection signal by the method described above. did. Then, based on the vent-up detection signal, the pressing mechanism 320 is driven, and the molten resin 70a leaking from the vent is pushed back into the plasticizing cylinder 210.

  Further, by rotating the screw 20 in the forward direction, the molten resin from which excess physical foaming agent (gas component) was separated was sent to the tip of the plasticizing cylinder 210, and the plasticizing measurement of the molten resin was completed. Thereafter, the shut-off valve 26 was opened, and the molten resin was injected and filled into the mold 252 adjusted to a temperature of 100 ° C. at an injection speed of 100 mm / s to obtain a foamed molded product. In contrast to the measuring stroke at the time of solid (non-foamed molded body) molding, which was 80 mm, in this example, injection filling was performed with a measuring stroke of 70 mm, and no holding pressure was applied. In the foamed molded product obtained in this example, fine cells having a cell diameter of 30 μm to 50 μm were formed, and the specific gravity was reduced by 15% compared to a non-foamed molded product produced from the same material.

  Although this example is a condition in which vent-up using a non-reinforced resin and a pressurized fluid is likely to occur, by using a vent-up prevention device, the vent resin is not blocked by the vent-up molten resin. A foamed molded product could be produced. In addition, in this example, a foam having fine foam cells equivalent to the foam molding method using a supercritical fluid was obtained although the introduction amount and pressure of the physical foaming agent were not controlled.

[ Reference example ]
In this reference example , the same non-reinforced nylon containing no inorganic filler as in Example 1 was used, and the molding apparatus 1000 shown in FIG. 1 was used. However, the non-reinforced nylon was not pre-dried and a physical foaming agent was used. A non-foamed molded product was produced without using.

In this reference example , the physical foaming agent is not supplied to the plasticizing cylinder 210, and the plasticizing metering of the thermoplastic resin is performed by rotating the plasticizing screw 20 forward at a constant rotational speed without rotating backward. Then, the mold was injected and filled with a measuring stroke of 80 mm, which is the production condition for solid (non-foamed molded body) molding, to produce a non-foamed molded body. In the vent-up prevention device 300, the back pressure valve 38 is opened, and the atmosphere around the vent-up detection mechanism 310 and the pressing mechanism 320 is set to atmospheric pressure. Except for this, vent-up of the molten resin was suppressed or prevented using the vent-up prevention device 300 in the same manner as in Example 1.

In this reference example , it was possible to produce a molded body without the vent being blocked by the molten molten resin. Further, the molded product obtained in this reference example was excellent in appearance characteristics, and no influence of moisture residue was observed even though the raw resin was not pre-dried.

The present invention has been described above with reference to the embodiments , examples, and reference examples . However, the present invention is not limited to the above-described embodiments , examples, and reference examples . Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress or prevent that a vent is obstruct | occluded by vent-up of the molten resin during molded object manufacture by using a vent-up prevention apparatus. Thereby, a molded object can be manufactured industrially stably stably.

30 Main body 30a Insertion part 31 Detection rod (moving member)
33 Magnetic sensor (detector)
32 Permanent magnet 34 Piston 35 Push-back piston 35b Cylindrical portion 35c Groove (slit)
36 discharge pipe 37 pressure gauge 38 back pressure valve 100 physical foaming agent supply device 200 kneading device 203 vent 210 plasticizing cylinder 300 vent-up prevention device 310 vent-up detection mechanism 320 pressing mechanism 250 mold clamping unit 252 mold 1000 molding device

Claims (10)

Used for foam molding using pressurized fluid as physical foaming agent,
Vent is formed, internally, a thermoplastic resin is melted plasticized and molten resin in the plasticizing cylinder to mix with the molten resin and the pressurized fluid, vent-up detection for detecting a vent-up of the molten resin Mechanism,
The vent-up detection mechanism is
A body connected to the vent of the plasticizing cylinder;
A moving member that is a detection rod movably held in the main body , wherein one end of the detection rod is inserted into the vent, and a permanent magnet is provided at the other end to vent up. and the moving member to which the molten resin is moved by contact with the end portion of the one,
A detection unit that is a magnetic sensor that detects a position displacement of a permanent magnet provided at the other end of the moving member in a non-contact manner;
A vent-up detection mechanism, wherein the atmosphere around the moving member is a pressurized atmosphere pressurized to an atmospheric pressure or higher by the pressurized fluid.   The atmosphere around the detection unit is atmospheric pressure,
  The vent-up detection mechanism according to claim 1, wherein the detection unit is a mechanism that detects a displacement of a permanent magnet provided on the moving member in a non-contact manner under atmospheric pressure. A vent-up prevention device,
The vent-up detection mechanism according to claim 1 or 2 ,
A pressing mechanism that is disposed in the main body and that pushes back the molten resin to be vented up into the plasticizing cylinder, based on a vent-up detection result from the vent-up detection mechanism;
The pressing mechanism has a piston that pushes back the molten resin into the plasticizing cylinder, and when the molten resin is pushed back into the plasticizing cylinder, a part of the piston is inserted into the vent. A vent-up prevention device. A vent-up prevention device,
The vent-up detection mechanism according to claim 1 or 2 ,
A pressing mechanism that is disposed in the main body and that pushes back the molten resin to be vented up into the plasticizing cylinder, based on a vent-up detection result from the vent-up detection mechanism;
When the pressing mechanism pushes the molten resin back into the plasticizing cylinder, a part of the piston has a cylindrical portion inserted into the vent;
A vent-up prevention device in which the moving member is movably held inside the cylindrical portion. A method for producing a foam molded article,
In a plasticizing cylinder formed with a vent for discharging gas components to the outside, plasticizing and melting the thermoplastic resin to make a molten resin;
Mixing a pressurized fluid as a physical foaming agent with the molten resin;
Separating a part of the gasified pressurized fluid as a gas component from the molten resin, and discharging the separated gas component from the vent to the outside of the plasticizing cylinder;
And that using a vent-up detection mechanism detects the vent up before Symbol molten resin,
Foaming the molten resin from which the gas component has been separated , and forming into a desired shape,
The vent-up detection mechanism is
A body connected to the vent of the plasticizing cylinder;
A moving member which is a detection rod movably held in the main body , wherein one end of the detection rod is inserted into the vent and a permanent magnet is provided at the other end ; ,
A detection unit that is a magnetic sensor that detects a position displacement of a permanent magnet provided at the other end of the moving member in a non-contact manner;
The atmosphere around the moving member is a pressurized atmosphere that is pressurized to atmospheric pressure or higher by a pressurized fluid,
Detecting the molten resin vent-up,
When the molten resin that vents up contacts the one end of the moving member, the moving member moves;
The manufacturing method of a foaming molding including the detection part detecting the position displacement of the permanent magnet provided in the other end of the moving member by non-contact.   6. The method for manufacturing a foam molded article according to claim 5, wherein the detection unit detects a displacement of a permanent magnet provided on the moving member in a non-contact manner under atmospheric pressure. The method for producing a foam molded article according to claim 5 or 6 , wherein the pressurized fluid is pressurized nitrogen or pressurized carbon dioxide. A molding apparatus for producing a foam molded article,
A vent that discharges gas components to the outside is formed, a screw is rotatably installed, a thermoplastic resin is plasticized and melted to form a molten resin, and the molten resin and a pressurized fluid are mixed as a physical foaming agent. A plasticizing cylinder;
A pressurized fluid supply device for supplying the pressurized fluid to the plasticizing cylinder;
A shaping | molding apparatus provided with the said vent up detection mechanism of Claim 1 or 2 connected to the said vent. A molding apparatus for producing a foam molded article,
A vent that discharges gas components to the outside is formed, a screw is rotatably installed, a thermoplastic resin is plasticized and melted into a molten resin, and a plastic fluid is mixed with the molten resin and a pressurized fluid as a physical foaming agent. A cylinder,
A pressurized fluid supply device for supplying the pressurized fluid to the plasticizing cylinder;
The vent-up prevention device and forming shapes device Ru comprising a according to claim 3 or 4 is connected to the vent. The plasticizing cylinder is formed with a high-pressure kneading zone for mixing the molten resin and the pressurized fluid, and the vent for exhausting the pressurized fluid gasified from the molten resin mixed with the pressurized fluid. Having a reduced pressure zone,
Furthermore, the shaping | molding apparatus of Claim 8 or 9 provided with the sealing mechanism which is provided between the said high pressure kneading zone and the said pressure reduction zone, and interrupts | blocks communication with the said high pressure kneading zone and the said pressure reduction zone.

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