JP2005280064A - Resin molding machine and resin molding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a plastic member, a plastic film, and a plastic fiber that do not release harmful organic molecules, conventionally, since the resin cannot be heated to a high temperature, the injection or extrusion pressure must be increased. It was heavy and high power consumption.
By adopting means for suppressing oxidative decomposition and decomposition due to catalytic effects, the molten plastic does not decompose or dissociate up to a high temperature, and becomes a molten plastic with extremely low viscosity. Therefore, film extrusion, capillary tube extrusion, and mold injection molding can be executed with very little extrusion and injection pressure, and the molding machine can be reduced in size and weight.
[Selection] Figure 1

Description

  The present invention relates to a resin molding machine and a resin molding method, and more particularly to an injection molding machine, a film extrusion molding machine, a fiber extrusion molding machine, and a molding method thereof.

  In resin molding, it is desired to produce a plastic member, a plastic film, and a plastic fiber that do not release any harmful organic molecules. Here, the harmful organic substance molecule usually means a low molecular weight component having a molecular weight of 1,000 or less. The reason is that when the molecular weight is 1,000 or more, the vapor pressure is so small that it is not released into the atmosphere. However, as the temperature increases, the molecular weight released shifts to the higher side, so that the molecular weight of the harmful low molecular weight organic substance varies accordingly. It is expected that such a resin molded product is manufactured with a molding machine that is as small, light, and low power consumption as possible.

  In the conventional resin molding technology, the molten resin is handled at a constant temperature so that the polymer material does not decompose and dissociate into a low molecular organic substance. Conventionally, such a temperature is, for example, about 280 ° C. As a result, the viscosity of the molten resin is high, so that a clamping pressure of 1,500 tons has been required. Since it is necessary to withstand such an extraordinary pressure, the molding machine is large and heavy, and power consumption is large. In order to reduce the injection pressure and mold clamping pressure, the viscosity of the molten resin must be lowered. For this reason, if the temperature of the resin is raised above about 280 ° C, the polymer resin decomposes and dissociates in conventional molding machines. I have.

  Also, for example, recent resin optical members are becoming thinner, larger, and finer in surface shape. In order to form the calculated optical shape, it is necessary to reduce the viscosity of the molten resin and ensure fluidity. It has come out.

  As a method for lowering the melt viscosity of the resin, there is a method for changing the characteristics of the resin itself. However, a method for easily reducing the viscosity of the resin material is to increase the temperature at the time of melting. However, increasing the melting temperature of the resin causes degradation and degradation of the resin as described above. The transparency of the optical member is important. In the resin molding step, the resin to be heated and melted is more likely to decompose and deteriorate as the temperature becomes higher. Further, when oxygen is present at the time of high-temperature melting, it reacts and is easily oxidized and deteriorated. Usually, the oxidation deterioration temperature is lower than the decomposition deterioration temperature in a state where there is no oxidizing atmosphere. The oxidized and deteriorated resin is colored or the refractive index is changed. Since these remain in the molded product as they are and become foreign matters, the transparency is lowered and the quality is deteriorated. In addition, the longer the residence time at high temperatures, the easier it is to undergo oxidative degradation. The foreign matters that have been oxidized and deteriorated and remain in the molded product are called burns, black spots, yellow, bumps, fish eyes, gels, and the like, and are a major cause of molding defects.

  As a countermeasure, recently, a molding machine having a structure in which the molding machine is sealed with nitrogen or air containing oxygen is forcibly exhausted has been developed and used.

  However, it is impossible to completely remove oxygen in the system, and it is impossible to eliminate defects completely. Further, if the residence time in the high-temperature molten state is shortened, the unmelted resin is extruded into the molded product as it is to cause a defect, so that it is very difficult to find optimum molding conditions.

  Accordingly, an object of the present invention is to provide a resin molding machine and a resin molding method capable of producing a plastic member, a plastic film, and a plastic fiber that do not emit harmful organic molecules.

  Another object of the present invention is to provide a resin molding machine that is small, lightweight, and has low power consumption.

  According to one aspect of the present invention, in a resin molding machine for molding a molten resin, there is obtained a resin molding machine characterized by having means for suppressing a polymer material from being decomposed or dissociated into a low molecular organic substance. It is done. Further, in the resin molding machine for molding the molten resin, the resin molding machine has means for reducing the viscosity of the molten resin while suppressing the polymer material from being decomposed or dissociated to become a low molecular organic substance, A resin molding machine characterized in that the pressure required for extrusion is reduced can be obtained.

  The means includes means for suppressing decomposition or dissociation due to oxidation. Preferably, the means includes means for setting the oxygen concentration in the atmosphere in contact with the raw material of the molten resin or the molten resin to 10 ppm or less. Preferably, the means further includes means for setting the concentration of moisture (H 2 O) in the atmosphere in contact with the raw material of the molten resin or the molten resin to 10 ppm or less.

  The resin is selected from the group consisting of acrylic resins, silicone resins, fluorine resins, polyimide resins, polyolefin resins, alicyclic olefin resins, epoxy resins, hydrocarbon resins, and fluorocarbon resins. It can be at least one of the following.

  It is also a feature of the present invention that the means includes means for setting the concentration of at least one of oxygen and moisture in a molten resin raw material or an atmosphere in contact with the molten resin to 1 ppm or less, and that the resin contains a hydrocarbon-based resin. . In this case, the concentration of at least one of oxygen and moisture is more preferably 0.1 ppm or less.

  Alternatively, the means includes a means for setting the concentration of at least one of oxygen and moisture in a molten resin raw material or an atmosphere in contact with the molten resin to 10 ppm or less, and the resin also includes a fluorocarbon resin. is there. More preferably, the concentration of at least one of oxygen and moisture is 1 ppm or less. The fluorocarbon-based resin is tetrafluoroethylene, hexafluoropropene, tetrafluoropropyne, hexafluorocyclobutene, hexafluoro-1,3-butadiene, hexafluoro-1-butyne, hexafluoro-2-butyne, octafluorocyclobutane, It may be at least one of octafluorocyclopentene, octafluoro-1,3-pentadiene, octafluoro-1,4-pentadiene, octafluoro-1-pentyne, octafluoro-2-pentyne and hexafluorobenzene.

  The granular resin raw material supplied as a raw material for the molten resin is brought into contact with an inert gas heated to a temperature lower than the temperature at which the resin raw material melts, the molten resin raw material is melted, the molten resin is an injection part or It is another feature of the present invention that at least one atmosphere of the portion moving to the extrusion portion, the portion where the resin is extruded from the elongated slit or small hole, and the mold injection molding portion is a high purity inert gas atmosphere.

  In the present invention, the means includes a material having a low catalytic effect on the molten resin that covers at least a part of a surface with which the molten resin comes into contact.

Preferably, the material contains Al or Cr in at least a part of the main component, and the resin contains a hydrocarbon resin. More preferably, the material includes trivalent chromium, aluminum oxide (Al ₂ O ₃ ), or chromium oxide (Cr ₂ O ₃ ).

  Alternatively, the material may contain Ni in at least a part of the main component, and the resin may contain a fluorocarbon resin. The material preferably includes at least one of plated Ni, Ni-P, Ni-B, and Ni-WP.

  The material may cover at least one surface of a screw, a cylinder, a housing, a nozzle, a blowing slit, a blowing hole, a mold, a die, and a roll.

  The resin is, for example, a resin for optical molded products, and may be a nonpolar polyolefin resin or a cycloolefin resin.

  The resin molding machine of the present invention can perform injection molding, film extrusion molding, or fiber extrusion molding. In injection molding, it is preferable to have a plurality of injection injection points, and it is also preferable to include a temperature control means in the mold driving means. When the temperature control means is water, it is preferable to use hydrogenated water. In order to remove static electricity from the resin molded product, it is preferable to provide soft X-ray irradiation means.

  In another aspect of the present invention, in the resin molding method including the first step of melting the resin and the second step of molding the molten resin by injection or extrusion, the first step and the second step A resin molding method characterized in that at least one of the above is performed while suppressing the polymer material from being decomposed or dissociated to become a low molecular organic substance. Further, in the resin molding method including the first step of melting the resin and the second step of molding the molten resin by injection or extrusion, at least one of the first step and the second step is a polymer. It is necessary to increase the temperature of the molten resin by decreasing the viscosity of the molten resin by suppressing decomposition or dissociation of the material into a low molecular organic substance, and is necessary for injection or extrusion for resin molding in the second step. A resin molding method characterized by reducing the pressure is obtained.

  At least one of the first step and the second step is performed while suppressing the polymer material from being decomposed or dissociated by oxidation. The reason is that at least one of the first step and the second step is performed with the oxygen concentration in the atmosphere in contact with the raw material of the molten resin or the molten resin being 10 ppm or less. Alternatively, at least one of the first step and the second step is performed at a moisture concentration of 10 ppm or less in a molten resin raw material or an atmosphere in contact with the molten resin. Alternatively, when at least one of the first step and the second step is performed, at least a part of the surface with which the molten resin comes into contact is covered with a material having a low catalytic effect on the molten resin. The other characteristics of the resin molding method of the present invention are the same as the characteristics of the above resin molding machine.

  In addition, the present invention also provides a method for producing a resin molded product characterized by molding using the above resin molding method.

  ADVANTAGE OF THE INVENTION According to this invention, the resin molding machine and resin molding method which can manufacture the plastic member which does not discharge | release harmful organic substance, a plastic film, and a plastic fiber are obtained. Moreover, in this invention, a resin molding machine can be made small size, lightweight, and low power consumption. By adopting means for suppressing oxidative decomposition and decomposition due to the catalytic effect as in the present invention, the molten plastic does not decompose or dissociate up to a high temperature, and becomes a very low viscosity molten plastic. Therefore, film extrusion, capillary tube extrusion, and mold injection molding can be executed with very little extrusion and injection pressure, and the molding machine can be reduced in size and weight.

  Hereinafter, the configuration and operation according to the present invention will be described.

  First, one of the requirements to be provided by the present invention is to suppress oxidative decomposition / dissociation so that the polymer material is not decomposed / dissociated to become a low-molecular organic substance. For hydrocarbon plastics, the O2, H2O concentration should be 1 ppm or less, preferably 0.1 ppm or less. For fluorocarbon plastics (PTFE, PFA, PVDF, etc.), the O2, H2O concentration should be 10 ppm or less, preferably 1 ppm or less. Thus, the inventors have found that oxidative decomposition / dissociation can be suppressed and the heating temperature can be increased. Based on this knowledge, in the present invention, before supplying the granular raw material to the hopper, moisture (H2O) and oxygen (O2) adsorbed on the surface or occluded in the raw material are removed from the granular raw material. A high-purity inert gas such as N2 gas is allowed to flow at as high a temperature as possible without causing the raw material to decompose. In addition, from the raw material charging hopper, the temperature of the plastic raw material is raised to produce a low-viscosity liquid plastic, the extrusion / injection part, the part that extrudes a film or fiber from a narrow, long slit or a hole with a narrow hole diameter, and gold The mold injection molding part is also replaced with a high purity inert gas such as N 2 atmosphere. This suppresses oxidative decomposition / dissociation.

  Also, according to the knowledge of the present inventor, molten plastic is sensitive to the catalytic effect of various surfaces that come into contact. For example, it has been found that the hydrocarbon-based resin is weak on the surface of Ni and stainless steel and stable to Al2O3 and Cr2O3, and the fluorocarbon-based resin is weak to stainless steel and Al2O3 and stable to Ni (NiF2). Considering the actual production, the surface with which the molten plastic contacts is Al-coated surface, Cr-coated surface (for example, 1 μm thick Ni-P base is plated with about 0.2 μm of trivalent Cr on the surface of the hydrocarbon resin. The Al2O3 surface and the Cr2O3 surface. For fluorocarbon resins, Ni surfaces, Ni-P plated surfaces, Ni-B plated surfaces, and Ni-WP plated surfaces are recommended.

  That is, one, a plurality, or all of the screw surface, housing surface, blowing slit or blowing hole surface, or mold surface must be as described above.

  By performing the above-mentioned treatment in consideration of the oxidative decomposition and the catalytic effect, the molten plastic does not decompose or dissociate up to a high temperature, and becomes a very low viscosity molten plastic. It is 400 ° C. for hydrocarbon-based cycloolefin, and 380 ° C. for fluorocarbon-based PTFE and PFA. Therefore, the film extrusion, the capillary tube extrusion, and the mold injection molding can be executed with very little extrusion and injection pressure.

  The embodiment of the present invention will be described with respect to an example of a mold injection molding machine.

  FIG. 1 is a sectional view showing an example of a resin molding machine of the present invention. A resin molding machine (injection molding machine) 8 according to an embodiment of the present invention shown in FIG. 1 includes a cylinder 5, a screw 4, a nozzle 6 and a mold 7. Pellets are supplied.

  Among these, since the screw 4, the cylinder 5, the nozzle 6, and the mold 7 are in contact with the molten resin, the surfaces that are in contact with the molten resin are covered with a material described later. Although an example of an injection molding machine has been described here, the present invention can be applied to an extrusion molding machine and a kneading machine in addition to an injection molding machine.

In the present invention, the injection pressure is drastically reduced to provide a compact, lightweight and ultra-low power consumption type device. As the main points (configuration requirements) of this embodiment,
(1) Make the temperature of the molten plastic as high as possible. For this purpose, melting and molding are performed in an N2 atmosphere in which O2 and H2O are blocked, and if the cycloolefin (representative of hydrocarbon-based plastic) is used, the surface of the resin contact portion is covered with a Cr plating base and a Cr2O3 film. The temperature can be raised to 370 to 380 ° C. Conventionally, the possible temperature is 280 ° C. or less, and the viscosity is 10 times or more. Further, in the case of PFA (a representative of fluorocarbon plastics), it is possible to reach 360 to 370 ° C. by plating the surface of the member with Ni. Conventionally, only 290 ° C. or less can be heated.

(2) Trivalent chromium plating (molding machine resin melting part and injection molding machine mold):
In hydrocarbon resin molding, in order to suppress decomposition, it is preferable to use a chromium plating surface because the surface of the chromium plating is naturally oxidized to form a chromium oxide film. However, it is preferable to use trivalent chromium so that the chromium oxide film is Cr2O3. Ordinary chromium plating uses hexavalent chromium, but hexavalent chromium is not preferable because the oxide film becomes CrO3. Hexavalent chromium is also undesirable because it is a harmful substance. The chrome plating is preferably used with a film thickness of about 0.2 microns. By the way, when realizing the mold surface in which the fine pitch is formed, the fine shape is processed on the plated surface by a diamond cutting technique or the like. However, when chrome plating is applied to the mold surface, the surface height is high and cutting is not possible. Therefore, after applying a plating process that is easy to process, such as nickel plating or Ni-P plating, as the foundation It is preferable to apply chrome plating.

(3) Use multi-point injection and increase the number of injection and injection points as much as possible.
In the case where kinks may be present on the side of the resin molded product, for example, 3 × 4 = 12 injection / injection points are provided in a matrix on the side of the mold. If there is a bulge on the side of the molded product, inject it from the side. In this case as well, a plurality of injection / injection points are provided on the long side. In the past, injection was performed at one injection point at a temperature of 280 ° C., and an injection pressure of 1,500 tons was required. In the present invention, when the injection point was set at 12 at 380 ° C., the injection pressure was 100 kg or less. It will be enough. Therefore, the mold clamping pressure and driving pressure of the mold can be made extremely small.

(4) If the output pressure can be reduced, the force applied to the mold will be very small. Therefore, the mold holding mechanism and other parts can be made extremely simple and small, and the heat capacity of the entire mold drive unit must be extremely small. Can do. In the mold driving jig, there is provided temperature control means capable of periodically repeating a high temperature of, for example, 150 to 160 ° C. and a low temperature of 25 to 40 ° C. on the mold surface. At the time of plastic injection injection, molten plastic is injected at a mold temperature of 150 to 160 ° C. Since the mold surface temperature is high, the plastic flows very quickly, and the extremely fine shape of the mold is transferred in detail. Since the mold surface temperature is high, there is no weld line at the joint even if multi-point injection is performed. When the injection process is performed, the temperature is lowered to 25 to 40 ° C. and the molded product is taken out. For this purpose, a temperature control refrigerant is injected into the mold drive jig and circulated. When using cooling water as a coolant, do not rust the metal. Use hydrogenated water to prevent bacterial growth. As the hydrogenated water, it is desirable to use pure water containing 0.1 to 1.6 ppm, preferably 0.2 to 1.0 ppm of hydrogen (saturated solubility of hydrogen in water at room temperature is 1.6 ppm). If hydrogenated water is not used, the machine will rust at once.

  By doing as mentioned above, the conventional injection pressure of 1,000 tons and 2,000 tons is not necessary, and an injection pressure of 10 kg / square cm or less is sufficient. As a result, the device can be miniaturized and a weight of 1/10 to 1/100 that of a conventional device is sufficient.

(5) Multi-molding (injection molding machine):
Since the viscosity of the resin is drastically reduced by the technique of the present invention, it is possible to flow the resin using piping and switch the flow path with a valve, and to flow into a plurality of molds. Productivity is dramatically improved by using multiple dies.

(6) Inert gas blowing during mold release (application to injection mold):
In the injection to the mold at the time of injection molding, when the molten resin viscosity decreases, the transferability of the resin to the mold surface is improved. For example, when having a fine pitch (groove) structure like a Fresnel lens or an optical disk, The pitch is densely filled, but as a result, the adhesion with the mold surface is improved and the molded product is not easily peeled off from the mold. The reason why it is difficult to peel off is that the mold and the molded product are in close contact with each other, so that a vacuum state occurs when the mold and the molded product are peeled off. Therefore, by introducing an inert gas into the mold pitch at the time of mold release, the vacuum state is released and it is easy to peel off. The inert gas is introduced from a portion that does not affect the quality of the molded product.

(7) Thickness adjustment of the extrusion molding machine is performed with a piezoelectric body (extrusion molding machine):
Usually, the thickness adjustment of an extruder such as a film, pipe or fiber is performed by controlling the temperature of the molten resin. However, this makes precise thickness control impossible. Therefore, it is preferable to adjust the thickness of the extruder with a piezoelectric body. The piezoelectric body is disposed in a die portion where the molten resin is extruded, and the number of piezoelectric bodies is adjusted and used as necessary.

(8) Static electricity, whether injection molding or film / fiber extrusion.
Usually, an ionizer using a discharge electrode is used for removing static electricity. However, if the ionizer is used in the atmosphere, O3 (ozone) is generated, and the plastic polymer is decomposed and dissociated to lower the molecular weight. Therefore, do not use ionizers that generate O3. In order to remove static electricity, it is preferable to remove static electricity without forming O3 by irradiating soft X-rays to the air with a soft X-ray generating tube having a wavelength of about 1 to 2 angstroms. Ionization of gas molecules occurs very efficiently even in an inert N 2 atmosphere, and static electricity is efficiently removed.

(9) The current injection molding machine realizes a strong injection pressure by slowly retracting the screw to the right once and protruding suddenly to the left when the resin is melted near the tip of the screw 4. This is because the viscosity of the molten resin is high. However, in the present invention, since the decomposition and dissociation of the molten resin can be suppressed and the temperature can be increased, the viscosity of the molten resin is extremely small. A plurality of mold parts shown in FIG. 1 are provided in parallel (for example, 4 to 6 pieces), and the screw is continuously rotated to continuously supply the molten resin. Continuous mold molding in which molten resin is sequentially supplied to the part by valve operation is realized. When the processed resin product is taken out from the first mold and the acceptability of the molten resin is adjusted, the next molten resin is injected by the valve operation. During this time, the molten resin flows one after another into the mold parts provided in parallel, and the mold forming process is continuously performed. It becomes a completely new molding method of resin.

(10) Figure 2 shows the temperature dependence of low molecular emission gas amount when low molecular emission gas generated during thermal decomposition of cycloolefin polymer on various metal material surfaces is measured by atmospheric pressure ionization mass spectrometer (APIMS). Show. The horizontal axis is the temperature of the metal surface, and the vertical axis is the sum of the intensities of the mass spectrum derived from the low molecular emission gas. It can be seen that the surface from which the released gas is generated at the lowest temperature is Ni. On the Ni surface, it can be confirmed that APIMS starts to detect low-molecular components released from thermal decomposition of the resin at around 350 ° C. Next, the surface of the austenitic stainless steel SUS316L electropolished surface (EP) at 360 ° C, SUS316L annealed surface (BA) at 370 ° C, and ferritic stainless steel FS9 surface treated with 200% Cr ₂ O ₃ passive state It can be seen that the temperature at which the gas released during decomposition is increased to 400 ° C. The material selected this time that did not generate the highest release gas due to decomposition and dissociation was the surface of austenitic stainless steel HR31 treated with 500Å Al ₂ O ₃ passive state, and cycloolefin up to 410 ° C. It was found that there is an effect of suppressing the thermal decomposition of the polymer. In the case of a cycloolefin polymer, that is, a hydrocarbon-based injection molding machine, for example, FIG. 1, the metal material constituting the cylinder 5, screw 4, nozzle 6 and mold 7 is subjected to Al ₂ O ₃ passive state. By using such a metal material, the decomposition and dissociation of the plastic due to the catalytic effect can be suppressed up to 410 ° C., so that the molding process by injection molding can be operated at a higher temperature. As a result, since it is in a molten state having a lower viscosity, molding can be performed with very little clamping pressure and injection pressure. That is, the injection molding machine can be reduced in size and weight. This function can also be applied to film extrusion machines for hydrocarbon resins, including cycloolefin polymers, and to capillary and fiber extrusion machines.

(11) Figure 3 shows the temperature dependence of the low molecular emission gas when the low molecular emission gas generated during the thermal decomposition of the cycloolefin polymer under various oxygen concentration atmospheres was measured with a Fourier transform infrared spectrometer. Results are shown. The material surface in contact with the cycloolefin polymer in this measurement is a Ni metal surface assuming Ni plating currently used on the surface of the mold. The horizontal axis represents the temperature of the Ni surface, and the vertical axis represents the intensity of infrared absorbance derived from the low-molecular emission gas. As can be seen from FIG. 3, the higher the concentration of oxygen coexisting in the gas phase, the lower the decomposition start temperature. In a 20% O ₂ atmosphere, low molecular emission gas due to thermal decomposition of cycloolefin polymer begins to be observed from 150 ° C. In an atmosphere that does not coexist with oxygen, emitted gas began to be observed around 300 ° C, but it was confirmed that there was a temperature difference of 150 ° C. In addition, when the coexisting oxygen concentration in the gas phase is 1 ppm or less, decomposition / dissociation due to oxidative decomposition can be suppressed, and decomposition of the material is rate-determined by thermal decomposition / dissociation due to catalytic action caused by Ni material. That is, by setting the oxygen concentration in the atmosphere in contact with the molten resin at the time of injection molding to 1 ppm or less, it is possible to reduce low molecular weight monomers due to oxidative decomposition of the resin. The high-purity nitrogen in which the oxygen / water concentration is controlled to 1 ppm or less is supplied into the hopper 9 filled with the raw material resin pellets in FIG. By providing the molding machine with a function of sufficiently removing oxygen and moisture, and making the atmosphere in which the molten resin of the cylinder 5, screw 4, nozzle 6 and mold 7 in the injection molding machine is a high-purity nitrogen atmosphere, oxidation is performed. Low molecular weight resin produced by decomposition can be reduced. It is possible to mold a highly functional resin material that sufficiently suppresses outgassing of the low molecular weight monomer having a high vapor pressure from the resin material into the gas phase and elution into the liquid phase. This function can also be applied to hydrocarbon resin film extrusion machines and thin tube / fiber extrusion machines.

(12) Figure 4 shows the low molecular emission gas temperature when the low molecular emission gas generated during the thermal decomposition of PFA resin, which is one of fluororesins, on the surface of various metal materials is measured with a Fourier transform infrared spectrometer. Indicates dependency. The horizontal axis represents the temperature of the metal surface, and the vertical axis represents the intensity of infrared absorbance derived from the low molecular emission gas. In contrast to the thermal decomposition of the hydrocarbon-based resin, it can be seen that the surface of the metal material having the effect of suppressing the released gas due to the thermal decomposition of the resin to a higher temperature is Ni. It can be seen that the release of C ₂ F ₄ gas generated by the decomposition of PFA can be suppressed up to around 380 ° C. to 390 ° C. Next, it can be seen that the NiF ₂ surface, the TaN surface, the Al ₂ O ₃ passivated stainless steel surface, and the SUS316L electropolished surface of SUS316L are cooled at lower temperatures. This result is the same with PTFE, and it is considered that an equivalent result can be obtained with a fluororesin-based resin material. Taking a fluororesin-based resin material injection molding machine, for example, FIG. 1 as an example, the metallic material constituting the cylinder 5, the screw 4, the nozzle 6 and the mold 7 is composed of a Ni-based metallic material, thereby providing a catalytic effect. Because the decomposition and dissociation of the PFA resin by 390 ℃ can be suppressed up to 390 ℃, the molding process by injection molding can be operated at a higher temperature. As a result, since it is in a molten state having a low viscosity, molding can be performed with extremely slight clamping pressure and injection pressure. That is, the injection molding machine can be reduced in size and weight. This function can also be applied to PFA resin film extruders and capillary / fiber extruders.

  The present invention can also be applied to the molding of fluororesin, PFA, fluorocarbon resin films, and the like. The molding machine of the present invention is effective for any molding machine used for resin molding. The molding machine used for resin molding is a machine for performing resin molding, such as an injection molding machine, a transfer molding machine, an extrusion molding machine, a blow molding machine, a compression molding machine, and a vacuum molding machine. Further, the present invention can be applied not only to a molding machine for obtaining a molded product, but also to an extrusion molding machine, a melt kneader, a roll kneader, etc. for adding a compounding agent or creating resin pellets. .

FIG. 1 is a sectional view of an injection molding machine as an example of the present invention. 4 is a graph showing temperature dependence of low molecular emission gas amount when low molecular emission gas generated during thermal decomposition of cycloolefin polymer on various metal material surfaces is measured by an atmospheric pressure ionization mass spectrometer (APIMS). It is a graph which shows the result of the temperature dependence of the low molecular emission gas at the time of measuring the low molecular emission gas generate | occur | produced at the time of the thermal decomposition of a cycloolefin polymer in various oxygen concentration atmosphere with a Fourier-transform infrared spectrometer. It is a graph which shows the temperature dependence of low molecular emission gas amount when the low molecular emission gas generated at the time of thermal decomposition of PFA resin is measured with a Fourier transform infrared spectrometer.

Explanation of symbols

4 Screw 5 Cylinder 6 Nozzle 7 Mold 8 Injection molding machine 9 Hopper

Claims (47)

  A resin molding machine for molding a molten resin, the resin molding machine comprising means for suppressing a polymer material from being decomposed or dissociated into a low molecular organic substance.   In a resin molding machine for molding a molten resin, it has means for reducing the viscosity of the molten resin while suppressing the decomposition or dissociation of a polymer material into a low molecular organic substance, and is used for injection or extrusion for resin molding A resin molding machine characterized by reducing the required pressure.   3. The resin molding machine according to claim 1, wherein the means includes means for suppressing decomposition or dissociation due to oxidation.   4. The resin molding machine according to claim 3, wherein said means includes means for setting the oxygen concentration in an atmosphere in which the raw material of the molten resin or the molten resin contacts to 10 ppm or less.   5. The resin molding machine according to claim 4, wherein the means further includes means for setting the concentration of moisture (H2O) in the atmosphere in contact with the raw material of the molten resin or the molten resin to 10 ppm or less.   6. The resin according to claim 1, wherein the resin is an acrylic resin, a silicone resin, a fluorine resin, a polyimide resin, a polyolefin resin, an alicyclic olefin resin, an epoxy resin, a hydrocarbon resin, and a fluorocarbon. A resin molding machine that is at least one resin selected from the group consisting of a resin.   4. The method according to claim 3, wherein the means includes means for setting the concentration of at least one of oxygen and moisture in the atmosphere in contact with the raw material of the molten resin or the molten resin to 1 ppm or less, and the resin includes a hydrocarbon resin. Resin molding machine.   8. The resin molding machine according to claim 7, wherein the concentration of at least one of oxygen and moisture is 0.1 ppm or less.   4. The method according to claim 3, wherein the means includes means for setting a concentration of at least one of oxygen and moisture in a molten resin raw material or an atmosphere in contact with the molten resin to 10 ppm or less, and the resin includes a fluorocarbon resin. Resin molding machine.   The resin molding machine according to claim 9, wherein the concentration of at least one of oxygen and moisture is 1 ppm or less.   The fluorocarbon resin according to claim 9 or 10, wherein the fluorocarbon-based resin is tetrafluoroethylene, hexafluoropropene, tetrafluoropropyne, hexafluorocyclobutene, hexafluoro-1,3-butadiene, hexafluoro-1-butyne, or hexafluoro-2. At least of butyne, octafluorocyclobutane, octafluorocyclopentene, octafluoro-1,3-pentadiene, octafluoro-1,4-pentadiene, octafluoro-1-pentyne, octafluoro-2-pentyne and hexafluorobenzene A resin molding machine characterized by including one.   The resin molding according to any one of claims 1 to 11, wherein the granular resin raw material supplied as a raw material of the molten resin is brought into contact with an inert gas heated to a temperature lower than a temperature at which the resin raw material melts. Machine.   In any one of Claims 1-11, the part by which the raw material of molten resin fuse | melts, the part to which molten resin moves to an injection | pouring part or an extrusion part, the part by which resin is extruded from an elongate slit or a small hole, and a mold injection molding part A resin molding machine characterized in that at least one atmosphere is a high purity inert gas atmosphere.   14. The resin molding machine according to claim 2, wherein the means includes a material having a low catalytic effect on the molten resin that covers at least a part of a surface with which the molten resin comes into contact.   15. The resin molding machine according to claim 14, wherein the material includes Al or Cr in at least a part of a main component, and the resin includes a hydrocarbon-based resin.   The resin molding machine according to claim 15, wherein the material includes aluminum oxide or chromium oxide.   15. The resin molding machine according to claim 14, wherein the material includes Ni in at least a part of a main component, and the resin includes a fluorocarbon resin.   The resin molding machine according to claim 17, wherein the material includes at least one of plated Ni, Ni-P, Ni-B, and Ni-WP.   The resin according to any one of claims 14 to 18, wherein the material covers a surface of at least one of a screw, a cylinder, a housing, a nozzle, a blowing slit, a blowing hole, a mold, a die, and a roll. Molding machine.   5. The resin molding machine according to claim 1, wherein the resin is a resin for optical molded products.   The resin molding machine according to claim 20, wherein the resin is a nonpolar polyolefin resin or a cycloolefin resin.   The resin molding machine according to any one of claims 1 to 21, wherein injection molding, film extrusion molding, or fiber extrusion molding is performed.   23. The resin molding machine according to claim 22, wherein the molding machine performs injection molding and has a plurality of injection injection points.   24. The resin molding machine according to claim 22, wherein the molding machine performs injection molding, and includes a mold driving unit and a temperature control unit installed in the mold driving unit.   25. The resin molding machine according to claim 22, wherein the molding machine performs injection molding, and the temperature control means includes hydrogenated water.   26. The method according to claim 22, wherein the molding machine performs injection molding, and includes soft X-ray irradiation means for removing static electricity from the resin molded product peeled from the mold. Resin molding machine.   23. The resin molding machine according to claim 22, wherein the molding machine performs film extrusion molding or fiber extrusion molding, and includes soft X-ray irradiation means for removing static electricity from the molded product.   In the resin molding method including the first step of melting the resin and the second step of molding the molten resin by injection or extrusion, a polymer material is used as at least one of the first step and the second step. A resin molding method, which is performed while suppressing decomposition or dissociation to form a low-molecular organic substance.   In the resin molding method including the first step of melting the resin and the second step of molding the molten resin by injection or extrusion, a polymer material is used as at least one of the first step and the second step. By suppressing decomposition or dissociation to become a low-molecular organic substance, the temperature of the molten resin is increased while lowering its viscosity, and the pressure required for injection or extrusion for resin molding in the second step A resin molding method characterized by reducing.   30. The resin molding method according to claim 28, wherein at least one of the first step and the second step is performed while suppressing decomposition or dissociation of the polymer material due to oxidation.   31. The resin molding method according to claim 30, wherein at least one of the first step and the second step is performed at an oxygen concentration of 10 ppm or less in an atmosphere in contact with the raw material of the molten resin or the molten resin.   32. The resin molding method according to claim 31, wherein at least one of the first step and the second step is performed with a moisture concentration in an atmosphere in contact with the raw material of the molten resin or the molten resin being 10 ppm or less. .   33. The resin according to claim 28, wherein the resin is an acrylic resin, a silicone resin, a fluorine resin, a polyimide resin, a polyolefin resin, an alicyclic olefin resin, an epoxy resin, a hydrocarbon resin, or a fluorocarbon. A resin molding method characterized by being at least one resin selected from the group consisting of a resin.   31. The method according to claim 30, wherein at least one of the first step and the second step is performed with a concentration of at least one of oxygen and moisture in the atmosphere in contact with the raw material of the molten resin or the molten resin being 1 ppm or less, and the resin Includes a hydrocarbon-based resin.   35. The resin molding method according to claim 34, wherein the concentration of at least one of oxygen and moisture is 0.1 ppm or less.   31. The method according to claim 30, wherein at least one of the first step and the second step is performed with a concentration of at least one of oxygen and moisture in an atmosphere in contact with a molten resin raw material or a molten resin being 10 ppm or less, and the resin Includes a fluorocarbon-based resin.   37. The resin molding method according to claim 36, wherein the concentration of at least one of oxygen and moisture is 1 ppm or less.   The resin molding method according to any one of claims 28 to 37, wherein a granular resin raw material is supplied as a raw material for the molten resin, and is brought into contact with an inert gas heated to a temperature below which the resin raw material melts. .   38. The resin molding method according to claim 28, wherein at least one of the first step and the second step is performed in a high purity inert gas atmosphere.   40. The material according to any one of claims 29 to 39, wherein at least a part of a surface with which the molten resin comes into contact when at least one of the first step and the second step is performed has a low catalytic effect on the molten resin. The resin molding method characterized by covering with.   41. The resin molding method according to claim 40, wherein the material contains Al or Cr in at least a part of a main component, and the resin contains a hydrocarbon-based resin.   42. The resin molding method according to claim 41, wherein the material includes aluminum oxide or chromium oxide.   41. The resin molding method according to claim 40, wherein the material includes Ni in at least a part of a main component, and the resin includes a fluorocarbon resin.   44. The resin molding method according to claim 43, wherein the material includes at least one of plated Ni, Ni-P, Ni-B, and Ni-WP.   45. The resin molding method according to claim 28, wherein injection molding, film extrusion molding, or fiber extrusion molding is performed in the second step.   46. The resin molding method according to claim 28, wherein the second step includes soft X-ray irradiation for removing static electricity from the molded product. 47. A method for producing a resin molded product, comprising molding using the resin molding method according to claim 28.

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