Resin molded body, and production method and apparatus of the same

Abstract

To provide a production method of a foamed molded body small in reduction of physical characteristics, having a smooth and clean surface, and high in an expansion ratio using a metallic mold incorporated with a mechanism for core back-foaming after filling a foamable resin in a mold cavity.SOLUTION: Foamability is given to a molten resin in a heating cylinder by dissolving or micro-dispersing steam generated by injecting water which is a substance not becoming a super critical state by a temperature and a pressure in a heating cylinder to a foaming agent and vaporizing by a temperature of the heating cylinder, and a temperature of a molten resin into a molten resin in a heating cylinder in a step of operating with a physical power such as kneading by rotation of a screw. Reduction of physical characteristics of the foamed article molded using a polymer alloy of the obtained PC-based resin given with foamability is small in comparison to a case of using an inorganic, organic chemical foaming agent, and an alcohol. Though a foam cell becomes large when using only water as a foaming agent, a fine foamed cell can be obtained using a foam formation nucleus agent.SELECTED DRAWING: Figure 15

Description

[Technical field]

[0001] The present invention relates to a resin injection foam molding process in which foam molding is performed using a foaming agent whose properties are gaseous and / or liquid and / or solid at 23°C and under a pressure of 1 atmosphere, i.e., NPT. To provide a means for obtaining a foamed molded product having a high expansion ratio by filling a cavity with a foamable resin using a mold structure having either a two-plate structure or a three-plate or more structure, and performing mold backing and / or core backing. [Background technology]

[0002] Patent Document 1 describes a foam molding method in which a molding material consisting of a resin (plastic) and a foaming agent is shot into a mold in which an insert is placed, leaving an unfilled portion, and the unfilled portion is filled by the expansion force caused by the foaming of the foaming agent. The resin consists of a base resin and a low molecular weight resin of the same type as the base resin but with a lower molecular weight than the base resin. Patent document 2 explains the Gas Counter Pressure (GCP) method as a means of suppressing swirl marks (foam stripes, abbreviated as "SM") that occur on the surface during foam molding, as well as the mold structure and the use of a U-shaped O-ring. Patent Document 3 describes and fully explains foam molding using a liquid, but does not specifically show in examples that water is the only foaming agent useful for foam molding of polymer alloys of PC and PC-based resins, or that the use of a foam nucleating agent to make foam cells finer. Patent Documents 4, 5, 6, and 7 describe a means for sealing an ejector pin with a load type O-ring, but do not describe a specific means for fixing an inclined pin for a slide core using a nest or the like, and further fixing the nest with a bolt to seal the rod of the inclined core with a load type O-ring. Patent Documents 4, 5, 6, and 7 explain the means of increasing the expansion ratio using a mold back and a core back, but in a mold with a structure of three or more plates, the expansion ratio cannot be increased unless the PL is opened first. There is no description of a structure that requires the PL to be forced to open first by using a spring or the like in the PL. Furthermore, there is no description of a mold structure that allows the PL to move back a certain amount (distance) by inserting a spring or the like in both the stripper plate and the PL when opening the stripper plate first, cutting the pin gate, and then opening the PL to perform mold back and core back. In Patent Document 4, Patent Document 5, Patent Document 6, and Patent Document 7, two sets of ejector plates are used, and a die structure having an ejector plate with an ejector pin, which is an extrusion shaft, and an outer cylinder, which retreats before fluid pressurization, is shown as a die device for pressure molding. In pressure molding, if gas gets into the molded product, it is no good, and it is shown that the outer cylinder is retreated before fluid pressurization to create a space so that the pressurized fluid can enter the gap between the mold and the resin, and the pressure of the pressurized fluid is dispersed and it does not become hollow, but in so-called hollow molding, in which the pressurized fluid is poured into the molded product to create a hollow section and pressurized from within the hollow section, after sufficient pressurization, the pressurized fluid inside the hollow section is no longer necessary, and a means of eliminating the residual pressure by retreating the gas injection pin (the fluid pressurization pin that forms a hollow section inside, the pin used for fluid pressurization) and exhausting it all at once is not shown to easily and reliably solve the problem of bulging in blow molding. Mitsubishi Gas Chemical Company, Inc. has shown a gas injection nozzle structure (Simpless Nozzle) equipped with a hydraulic cylinder for blow molding, but the hydraulic cylinder gets in the way and gas cannot be injected at the desired location.Also, when gas injection from multiple locations is required, the installation of the ejector pins on the mold is greatly restricted by the gas injection nozzle equipped with the hydraulic cylinder. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 08-103919 [Patent Document 2] Japanese Patent Application Publication No. 11-216748 [Patent Document 3] International Publication No. 2003 / 026357 [Patent Document 4] International Application No. PCT / JP2015 / 062611 [Patent Document 5] International Application No. PCT / JP2015 / 069216 [Patent Document 6] International Application No. PCT / JP2016 / 086380 [Patent Document 7] International Application No. PCT / JP2020 / 15536 DISCLOSURE OF THEINVENTION

[0004] (Problem to be solved by the invention) The objective of the present invention is to obtain a foam-molded product with a high expansion ratio by filling the cavity with a foamable resin, followed by mold-backing and core-backing to open the cavity. (Means for solving the problem)

[0005] The mold is equipped with a mechanism (pre-mold opening mechanism, mold opening mechanism, mold opening mechanism) that forcibly opens the PL of the mold when mold back or core back is performed.

[0006] (composition) It takes time to open the exhaust valve and naturally exhaust the gas in the molten resin, which reduces productivity and is not economical. If the mold is opened with residual pressure remaining, it will swell and burst. By separating the tip 143 of the gas injection pin 120 from the boss 123, a new exhaust circuit is created, and the gas that formed the hollow part remaining in the hollow part is exhausted, making the pressure inside the hollow part the same as atmospheric pressure. In the present invention, "or / and" refers to either A or B, and "and" refers to both A and B. Also, " / " is a symbol that distinguishes between "or" and "and." In the case of foam molding, the Gas Counter Pressure (GCP) method is classified into outer (from outside the molten resin, from the outside, from outside, from outside the molded product, from the outside, from the outside) GCP {; a sealed mold is used to pressurize the inside of the cavity with a pressure above atmospheric pressure in advance, and in this invention, simply "GCP" refers to this outer GCP (O-GCP).} and inner (; from inside the molten resin, from the inside, from inside, from inside the molded product, from the inside, from the inside) GCP. A hollow part is formed inside using a foamable resin, and by evacuating the gas inside the hollow part, the foamable resin starts to foam toward the inside of the hollow part, and part or all of the internal hollow part is filled with a foam layer. This is called inner GCP (I-GCP). The structure of the mold of the present invention shown in FIG. 25 is similar to that of FIG. 55, FIG. 65, FIG. 66, FIG. 67, and FIG. 72 of International Application No. PCT / JP2016 / 086380 (hereinafter referred to as "Patent Document 6") of Patent Document 6, but the molding method in Patent Document 6 is compressed air molding, which is different from the blow molding of the present invention. The present invention is a blow molding mold (FIG. 25) that puts a high pressure gas into the molded product. If it is only blow molding, there is no need to provide O-rings such as numbers 69, 72, 102, and 103. In the present invention, GCP is performed and blow molding is performed, so these O-rings are used to make a seal mold. Of course, blow molding can be performed even with a mold with O-rings such as 69-103. On the other hand, the dies in Fig. 55, Fig. 65, Fig. 66, Fig. 67, Fig. 72 of Patent Document 6 are dies for pressure molding in which high pressure gas is injected into the gap between the resin and the die and pressurized by the pressure of the gas, so the reference number 226 in Fig. 55 of Patent Document 6 goes down first, creating a small space in the gas ejection section, and high pressure gas is injected into it, so it does not become a hollow molding (high pressure gas does not enter the molded product). Since it becomes a hollow molding, which goes against the purpose of performing pressure molding, the device to avoid hollow molding is shown in detail in Fig. 55, Fig. 65, Fig. 66, Fig. 67, Fig. 72 of Patent Document 6. On the other hand, in Fig. 25 of the present invention, the device to inject high pressure gas into the molten resin filled in the molding space is the boss reference number 123. The mechanism consisting of the reference numbers 117, 118, 120, etc. is for completely exhausting the gas remaining in the hollow portion after blow molding and making the residual pressure zero, so that the operation, purpose, action and effect are completely different from those of Patent Document 6, and this shows the difference between Patent Document 6 and the present invention. Note that "high pressure" means gas with a pressure higher than atmospheric pressure.

[0007] (Action and effect) In the first invention described above, if the mold is opened while the high-pressure gas that formed the hollow portion remains inside the hollow portion, the molded product will swell and burst. Therefore, by separating the gas inlet (for example, tip 143 of 120) from the molded product 123, creating a new exhaust circuit, and exhausting the gas so that the pressure inside the hollow portion is the same as atmospheric pressure, a hollow molded product with a hollow portion inside without swells or bursts can be obtained.

[0008] In the case of foam molding using foamable resin, by discharging gas into the inner hollow space due to the high pressure, the inner hollow space has not yet cooled or solidified, so a foam layer is formed in the hollow space. This is called the "inner GCP".

[0009] Even in the case of foam molding using foamable resin and performing mold-back or core-back, if high-pressure gas is applied from the inside (if an inner GCP is used), the part will not separate from the mold, and mold reproducibility will increase (improve).

[0010] (composition) In the second invention described above, before the process of filling the cavity with foamable resin and / or non-foamable resin, a gas injection and exhaust mechanism (for example, 117, 118, 120, 143, etc., hereinafter referred to as the "gas injection mechanism") consisting of reference numbers 117, 118, and 120 is advanced and retreated by an ejector rod, or by a mechanism such as a hydraulic or pneumatic cylinder or motor built into the mold. When filling the cavity with molten resin, the gas injection mechanism advances first, and reference number 120 is made to be in a state where it is inserted into reference number 123 (before filling with molten resin, it is a space). After filling with molten resin and taking a delay time as necessary, a gas with a large pressure is injected into the molten resin to form a hollow space. This time is called the "injection time". The injection pressure and injection time at this time are variable depending on the type of resin used, the shape of the molded product, the molding conditions, etc., and are injected at optimal settings.

[0011] The gas injected into the hollow space at high pressure is trapped there for a certain period of time, if necessary. This is called the "retention time."

[0012] After the holding is finished, the gas due to the high pressure inside the hollow is exhausted to the atmosphere through the gas injection pins 143 and 144 shown in Figures 27 and 28. In the middle of the exhaust, when the exhaust is almost completed, the gas injection mechanism consisting of the reference numbers 117, 118 and 120 is retracted. By retracting, the reference number 120 moves away from the reference number 123, and a new exhaust circuit is created, and the gas is completely exhausted and the pressure inside the hollow becomes the same as the atmospheric pressure.

[0013] When the resin used is a foamable resin, the timing of retraction may be when the pressure in the hollow part drops to approximately atmospheric pressure. Also, if 120 is retracted when the pressure in the hollow part drops to about 1 MPa, the same as the GCP, the pressure in the hollow part (inner GCP) is released all at once, and foaming begins in the hollow part.

[0014] The mold is clamped (closed) and the gas injection pin 120 (which also has an exhaust function) is advanced. Next, when the exhaust of the gas in the hollow is almost completed, the gas injection pin 120 is advanced and retreated. This forward and backward movement is generally performed by the ejector rod of the molding machine, but urethane rubber, springs, gas springs, hydraulic or pneumatic cylinders, or other mechanical mechanisms may be provided separately in the mold. The urethane rubber, springs, gas springs, etc. are mainly incorporated for the purpose of retreat. In the previously disclosed hollow molding method, the SYMPRESS, a mechanism called the SYMPRESS nozzle was used, but in this case, a hydraulic cylinder of about φ70 mm was incorporated in the mold, for example, in the movable mold plate. This resulted in many restrictions on the mold design, such as the ejector pin not being able to be installed in this part, or the gas not being able to be injected from the desired location of the molded product.

[0015] When using a hydraulic cylinder or the like instead of the ejector mechanism of the molding machine, that mechanism is incorporated in 80 in Fig. 25 (urethane rubber, springs, gas springs, air pressure, hydraulic cylinders, and other mechanical mechanisms are not shown in Fig. 25). This makes it possible to inject a large amount of gas from any position. Also, there are no restrictions on ejector pin installation like with the Simpress nozzle, and no restrictions on mold design.

[0016] (Action and effect) The second invention described above solves the problem of bulging and bursting due to residual pressure inside the hollow part by retracting the mechanism that forms the hollow part in the molded product, eliminating the residual pressure inside the hollow part, and making the pressure the same as atmospheric pressure.

[0017] In particular, in the case of mold back and core back, which are carried out to increase the expansion ratio, the mold is retracted while being pressurized from the inside with high pressure gas, so the foamed product does not leave the mold, resulting in high mold reproducibility.

[0018] (composition) The third invention described above advances a mechanism for injecting high pressure gas into the molten resin, for example, consisting of the ejector rod of the molding machine, or a polyurethane rubber, spring, gas spring, pneumatic or hydraulic cylinder, or other mechanical mechanism incorporated in the mold, such as reference numbers 117, 118, and 120. The mechanism for injecting high pressure gas into the molten resin, consisting of the above-mentioned reference numbers 117, 118, and 120, is retracted by the force of a hydraulic or pneumatic cylinder or other mechanical mechanism provided between 117 and 101. Of course, the ejector rod may be connected to, for example, 118. In this case, a magnet may be provided, for example, at the tip of the ejector rod (or on the 118 side of the portion where the ejector rod and 118 contact). In this case, the springs, urethane rubber, etc. of the mechanism for returning the reference numbers 117, 118, and 120 described in the third invention are not necessary.

[0019] (composition) After a gas of high pressure is injected into the filled molten resin, held therein, and exhausted, in order to retract the gas injection mechanism consisting of, for example, 117, 118, and 120, if the mechanism is advanced using an ejector rod, the gas injection mechanism consisting of 117, 118, and 120 does not retract simply by retracting the ejector rod, so it is necessary to incorporate some mechanism (function) for retracting the gas injection mechanism into the mold. In the fourth invention, the retraction mechanism is provided between 101 and 117, for example, in a urethane rubber, spring, gas spring, hydraulic or pneumatic cylinder, or other mechanical mechanism, and is retracted by a signal from the molding machine or a sequencer provided externally. This command may be given only by a program written in the program in the sequencer of the molding machine, or may be given by using the program of the molding machine in combination with an external sequencer (signal exchange).

[0020] (composition) In the fifth invention described above, after a gas under high pressure is injected into the filled molten resin, held therein, and exhausted, in order to retract the gas injection mechanism consisting of, for example, 117, 118, and 120, if the mechanism is advanced using an ejector rod, the gas injection mechanism consisting of 117, 118, and 120 cannot be retracted by simply retracting the ejector rod, so some kind of retraction mechanism must be incorporated into the mold. Advancement and retraction are performed by polyurethane rubber, springs, gas springs, hydraulic or pneumatic cylinders, or other mechanical mechanisms within the mold, and the program for this operation is incorporated into a sequencer within the molding machine, and the mechanism is operated by the sequencer incorporated within the molding machine. In the fifth invention, the retraction mechanism, for example, urethane rubber, springs, and gas springs are incorporated mainly for the purpose of retraction, and are provided between 101 and 117, and the gas injection mechanism retracts in accordance with the retraction of the ejector rod. Since hydraulic or pneumatic cylinders or other mechanical mechanisms are used for forward and backward movement, the inventors mainly incorporated them into the mounting plate on the movable side. The purpose of the urethane rubber, springs, and gas springs is to retract the gas injection mechanism, so the forward movement is performed by the ejector rod, and when the ejector rod is retracted, the gas injection mechanism retracts as the urethane rubber, springs, and gas springs expand. Hydraulic or pneumatic cylinders and other mechanical mechanisms can be either forward or retracted. In either case, they are retracted by a signal from the molding machine.

[0021] (composition) The sixth invention described in claim 6 is a method of carrying out the steps described in the first invention described above in a sealed mold in which the inside of the mold is pressurized in advance with a gas at atmospheric pressure or higher (outer GCP).

[0022] (Action and effect) In the sixth invention described in claim 6, a foamable resin is filled into a mold that has already been pressurized, so that a skin layer is formed on the molded product and a foam layer is formed inside. The surface is smooth and clean, free of swirl marks caused by the foaming agent, due to the pressurization inside the mold (outer GCP), and by making the inside hollow (inner GCP), a foam molded product with a high expansion ratio can be obtained.

[0023] In the process described in claim 6, if the mold is further recessed (expanded into the cavity) by molding back or core back, the expansion ratio can be further increased.

[0024] (Configuration, Action, Effect) In claim 7, the use of a non-foaming resin instead of a foaming resin has the effect of eliminating silver streaks that occur due to moisture and other volatile components contained in the resin before molding. When using molding materials containing inorganic fillers such as talc or glass beads, the action and effect of the outer GCP pushes the inorganic fillers into the molded product, making them invisible on the surface, resulting in molded products with a beautiful surface. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] (Definition of terms) First, the terms used in the present invention will be defined. "Mold cavity" refers to the space filled with foamable and / or non-foamable resin in injection molding, block molding, or casting molding. "Inside the cavity" refers to the interior, space, or volume of the mold cavity. "Cavity" is synonymous with "mold space." In injection molding, when the first mold (generally the fixed mold) and the second mold (generally the movable mold) are joined together, a space defined by the first and second molds is created. This space is the "cavity" and refers to the space filled with foamable resin and / or non-foamable resin, and is sometimes simply called the "cavity." The pushing shaft mainly refers to the ejector pin installed in the second mold, but also includes the inclined pin and kicker pin of the slide core.

[0026] In addition to the injection molding exemplified above, the present invention can also be implemented by sheet extrusion molding, profile extrusion molding, blow molding, and the like, depending on the ingenuity of the die.

[0027] "Injection" refers to the process of filling, injecting, or pouring foamable and / or non-foamable resin into a mold cavity. "Extrusion" refers to the continuous extrusion molding of a heated and molten foamable resin and / or a non-foamable resin through a die. This includes a method of mixing a non-foaming resin and a foaming resin in the extruder nozzle (mixing them together and calling it mixed) to give them foamability, and a method like the Niho Method of mixing gas and / or liquid with the heated and melted resin in the extruder nozzle to give them foamability. Of course, the Niho Method is also an effective method for injection foam molding.

[0028] "Blow" refers to the technique of placing a parison in a mold and pressurizing it with air or other gas from inside the parison to form it. If the parison is made of foam resin, this is blow molding using foam resin.

[0029] "Filling" refers to filling the mold cavity with foamed resin and / or non-foamed resin in processes such as injection molding and block molding. Filling an amount less than the volume of the mold cavity is called a short shot or short mold, filling an amount equal to the volume is called a full shot or full pack, and filling an amount greater than the volume is called an overshot or overpack. In order to reduce sink marks or improve transferability (UP, UP, Up), if pressure is applied to the resin from the molding machine heater barrel after the full shot, this invention clearly indicates that pressure is used. In the case of block molding, the distinction between non-pressurized and pressurized is made clear, such as non-pressurized after filling and pressurized after filling. "Pressurization" refers to applying a fluid pressurized to the resin at atmospheric pressure or higher.

[0030] "Resin in the heating cylinder" refers to thermoplastic resin in a solid (solid) state such as pellets, bulk, or powder before being heated and melted, in the middle of being plasticized, or in a molten state after plasticization is complete.

[0031] The properties of "foaming agents" can be gas, liquid, or solid, and are broadly classified into physical and chemical foaming agents, each of which can be inorganic or organic. Gases include inert gases such as nitrogen gas, carbon dioxide, helium, argon, and other rare gases, and flammable gases such as hydrogen, and these are used alone or as mixed gases (mixed fluids). Liquid foaming agents refer to substances that are liquid at NTP (Natural Temperature Pressure, Natural Temperature and Pressure, Normal Temperature Pressure, Normal Temperature and Pressure = temperature of 23°C and pressure of 1 atmosphere (1 atm, 760 mmHg)), and include monohydric alcohols such as ethanol (EtOH) and propanol (mainly isopropanol, iso-PrOH in this invention), dihydric or higher alcohols, ethers, esters, ketones, etc., vaporizable substances such as distilled water, ion-exchanged water, city water (tap water), and well water, sodium bicarbonate water, sodium citrate water, etc. that use these substances as solvents, and liquefied carbon dioxide gas (liquid carbon dioxide) liquefied by pressurization and cooling, etc. Solids include inorganic thermal decomposition types of chemical foaming agents such as hydrogen carbonates, carbonates, nitrites, hydrogen compounds, carboxylic acids, and carboxylates. Microballoons (macroballoons, microballoons) such as Advancel (trade name), copper sulfate containing structural water {copper sulfate pentahydrate, (now called "hydrate" rather than the concept of "crystal water"), of course, these 5 moles of structural water also vaporize in the heating cylinder at the temperature of the heating cylinder and the temperature of the molten resin heated and melted, and the water vapor acts as a foaming gas.}, silica gel soaked in water to be hydrated, ABS soaked in water for a long time, for example about 6 hours, and the surface moisture is removed by centrifugation or the like to be hydrated (ABS), PC and PC-based resins (PC / ABS in this case) soaked in water like ABS, and soaked in water to be hydrated can also be used as foaming agents because the moisture vaporizes in the heating cylinder like the structural water and functions as a foaming agent. These are examples of water, but it is not limited to water, and organic solvents such as alcohol may also be used.Although it is an extreme example, rice that has been soaked in water to absorb moisture can also be used as a foaming agent. Of course, solid carbon dioxide (dry ice) is also a solid foaming agent. When dry ice is mixed with pellets and placed in a hopper and then in the heating cylinder, the dry ice vaporizes immediately and the vaporized carbon dioxide escapes from the hopper, so a plug (such as a back melter) should be placed in the hopper during plasticization measurement to prevent the carbon dioxide from escaping. Alternatively, a preferred method is to drill a hole in the heating cylinder and use a mechanism such as a feed screw to measure the amount and steadily add a fixed amount to the molten resin.

[0032] Inorganic thermal decomposition type blowing agents include hydrogen carbonates and carbonates such as sodium hydrogen carbonate, potassium hydrogen carbonate, and lithium hydrogen carbonate (Li) as mentioned above, while organic thermal decomposition type blowing agents include azo compounds, hydrazine derivatives, semicarbazide compounds, azide compounds, nitroso compounds, and triazole compounds, and reactive types include isocyanate compounds. Examples include ADCA {azo di(di) carboxylic acid amide}, HDCA (hydro dicarboxylic acid amide), azo dicarboxylate (ADCA Ba salt), HDCA Ba salt, DPT (dinitroso pentamethylenetetramine), OBSH {P-P'-oxybis(benzenesulfonylhydrazide)}, and AIBN (azo bis isobutyronitrile) (listed above). Details of blowing agents and foam molding are described in Various Polymers and Foam Molding Technology, published by the Technical Information Association in August 1993. In the case of carbonates or bicarbonates (alkali metals or alkaline earth metals), an equivalent amount (neutralization reaction with basic carbonate or bicarbonate) of a weakly acidic substance such as citric acid or disodium hydrogen citrate may be used in combination.

[0033] When using a liquid as a foaming agent for thermoplastic resin, the optimal volume (vol.) for the weight (wt.) of the molded product is measured (weighed) and injected into the thermoplastic resin in the heating barrel all at once or continuously, and vaporized or / and thermally decomposed or / and chemically reacted depending on the temperature of the heating barrel and inside the heating barrel, the temperature of the molten thermoplastic resin in the heating barrel, or / and the temperature of the nozzle, or / and the temperature of the mold, to generate a foaming gas useful (effective) for foam molding. The temperature of the liquid to be injected is room temperature, but it may be heated if necessary to shorten the time until vaporization. The pressure of the liquid may be increased to a level higher than the pressure that can be injected into the heating barrel, raising the boiling point before injection.

[0034] The generated gas is finely dispersed and / or pressurized and dissolved in the molten resin in the heated barrel by the physical force of the metering stage and the physical force of the filling stage, and the thermoplastic resin in the heated barrel becomes a foamable thermoplastic resin. This can be filled into the mold cavity to produce a molded product with a foamed structure. In other words, "foam molding" refers to the process of obtaining a foamed structure by filling a mold with a resin that has been given foamability by dispersing and / or dissolving (including pressurized dissolving) a foaming gas into the resin in the heated barrel. Note that in the case of extrusion, a die is used instead of a mold.

[0035] "Giving foamability to molten resin" means that in the case of gas {gas (e.g. nitrogen gas)}, large lumps of foaming gas (nitrogen gas) are dispersed by the force of screw rotation, and pressurized melting by back pressure, or / and finely dispersed in molten resin. In the case of liquid, foaming gas is generated by vaporization, thermal decomposition, etc. depending on the temperature inside the heating cylinder and the temperature of the molten resin, and the foaming gas is dispersed by the force of screw rotation, and pressurized melting by back pressure, or / and finely dispersed in molten resin. In the case of solid foaming agents, it means that foaming gas generated by chemical reaction is dispersed by the force of screw rotation, and pressurized melting by back pressure, or / and finely dispersed in molten resin. In the case of micro (macro, micro) balloons, it also means that the generated foaming gas is dispersed by the force of screw rotation, and pressurized melting by back pressure, or / and finely dispersed in molten resin. It is desirable for the screw to have a high rotation torque and a high rotation speed. Increasing the back pressure improves the mixing ability and the dispersion of the foaming gas. This includes cases where the nozzle has an inlet for the gas foaming agent, an inlet for the liquid foaming agent, and where the heated and melted foamable resin is mixed with the non-foamable resin. If necessary, the screw may have a dulmage or the like.

[0036] "Foaming" refers to the state where the foaming gas is suppressed by external pressure, such as the GCP (outer GCP), back pressure, injection pressure, etc. (compressed into the resin and finely dispersed in a small volume, or / and pressurized and dissolved), and the volume of the foaming gas in the resin increases, or / and the foaming gas that was pressurized and dissolved becomes gas, when the external pressure is reduced or eliminated. "Foaming" also refers to the process in which a foamable thermoplastic resin is extruded from a heating cylinder and foams, or the process in which a foaming gas is generated by the vaporization, thermal decomposition, or chemical reaction of a liquid or solid foaming agent.

[0037] "Foaming" refers to the process of finely dispersing and / or pressurizing and dissolving foaming gas in a molten thermoplastic resin, and then lowering the pressure to form foam cells inside and / or on the surface of the thermoplastic resin {The foam cells (bubbles) that appear on the surface are swirl marks.} In the case of thermosetting resins, the foaming agent is heated, vaporized, thermally decomposed, and chemically reacts to generate foaming gas, which forms foam cells inside and / or on the surface of the thermosetting resin. Molded products with foam layers inside and / or outside due to foaming in this way are called foam molded products or foam structures.

[0038] "Foamable resin" refers to a thermoplastic resin or thermosetting resin in a molten state in which a foaming gas useful for foam molding has been finely dispersed and / or dissolved under pressure. In other words, "foamable resin" refers to a thermoplastic resin or thermosetting resin containing a gaseous foaming agent, a liquid foaming agent, or a solid foaming agent. In the present invention, the state of the resin is described as "a thermoplastic resin having foamability in a molten state," "a thermoplastic resin containing a foaming agent, or a thermosetting resin containing a foaming agent," and the state of the resin is described as accurately as possible, such as the fact that the resin has foamability, that the resin contains a gaseous foaming agent, a liquid foaming agent, or a solid foaming agent. Note that the foaming agent may be a combination of liquid and solid, a combination of gas and solid, or several types of gas alone. In the case of a liquid, a mixture of alcohol and water may be used.

[0039] "Foam-molded products" refer to resin-molded products that have discontinuous foam cells inside, and are produced by molding foamable thermoplastic resins or thermosetting resins. The average size of the foam cells is 5,000 μm {microns (μ), micrometers (μm)} or less. In the present invention, foam-molded products are also considered to be foam-molded products when hollow parts and foam cells are mixed in a hollow molding process using foamable resins.

[0040] "Combined use" also refers to using or combining something with another thing. For example, one molding process method can be effective, but it can also be used in combination with another method, creating a synergistic effect or improving one or / and both effects. Foaming agents may also be used in combination with several types rather than alone. Gas, liquid, and solid foaming agents may also be used in combination.

[0041] "Foaming assistant" refers to a substance used to lower the decomposition temperature of the foaming agent or to promote the decomposition of the foaming agent. Examples of foaming assistants for organic foaming agents include zinc stearate, barium stearate, metal soap, urea (which has the effect of lowering the decomposition temperature of ADCA), zinc oxide, etc. Inorganic and organic acids (such as citric acid and sodium hydrogen citrate) used to decompose carbonates and hydrogen carbonates can also be considered foaming assistants. However, in the case of PC-based resins, there is a risk of decomposition, so it is necessary to check in advance whether the physical properties will be reduced by adding each substance. In particular, basic oxides (another word for metal oxides) such as CaO, BaO, and Cs2O have a high risk of decomposing the PC in PC-based resins.

[0042] (Foam nucleating agent for PC resins, foam nucleating agent) "Foaming (foaming) nucleating agents, bubble nucleating agents" are substances that are mixed with the resin and foaming agent to be molded in order to form fine foam cells. Foaming nucleating agents utilize the difference in specific heat between the molten resin and the foaming nucleating agent to create small sinks (spaces) at the boundary between the molten resin and the foaming nucleating agent, and foaming begins with these sinks as nuclei (the sinks = the small spaces where the foaming gas gathers and the foaming gas starts to gather and foaming begins), forming foam cells. In this way, foaming nucleating agents utilize temperature differences {(differences in specific heat, differences in the rate of heating, differences in the rate of cooling) (when the foaming nucleating agent is heated, it becomes warmer than the surrounding molten resin, or conversely, when it becomes cooler)} to bring about the effect of finely dividing foam cells. Examples of foam nucleating agents include metal powders such as aluminum (Al), titanium (Ti), nickel (Ni), cobalt (Co), iron (Fe), copper (Cu), silver (Ag), W (tungsten), and Cr (chromium), non-metal powders such as silicon (Si) and germanium (Ge), and oxides, nitrides, and carbides of these metals.

[0043] In addition, flame retardants can also be foam nucleating agents, and provide the action and effect of foam nucleating agents. Halogen-based flame retardants, such as brominated epoxy, phosphate-based flame retardants, such as trimethyl phosphate, triethyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, cresyl di-2,6-xylenyl phosphate, non-halogen phosphate esters, such as DAIGUARD-1000 (trade name) and aromatic condensed phosphate esters, such as CR-7335 (trade name), CR-741 (trade name), and aromatic condensed phosphate esters, such as PX-200 (trade name). Examples of such phosphate esters include non-halogen phosphate esters represented by {TMCPP (trade name)} and tris(tribrimoneopentyl) phosphate {CR-900 (trade name)}, halogen-containing phosphate esters represented by {CR-504L (trade name)}, {CR-570 (trade name)}, and {DAIGUARD-540 (trade name)}, and non-halogen condensed phosphate esters represented by {DAIGUARD-580 (trade name)}, {DAIGUARD-880 (trade name)}, and {DAIGUARD-850 (trade name)}.

[0044] In addition, fine particles of fluorine-containing resins such as polytetrafluoroethylene (tetrafluoride) (abbreviation: PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (abbreviation: PFA), tetrafluoroethylene-hexafluoropropylene copolymer (4.6 fluoride) (abbreviation: FEP), tetrafluoroethylene-ethylene copolymer (abbreviation: ETFE), polyvinylidene fluoride (difluoride) (abbreviation: PVDF), polychlorotrifluoroethylene (trifluoride) (abbreviation: PCTFE), and chlorotrifluoroethylene-ethylene copolymer (abbreviation: ECTFE), which are used in combination with the above flame retardants, also act as foam nucleating agents. Metal particles with nano-sized particles also act as foam nucleating agents.

[0045] For example, when water is used as a blowing agent, the foam cells are smaller in ABS than in AS. When comparing PS and HIPS, the foam cells are smaller in HIPS, just like ABS. This is because the rubber (graft rubber) made by graft copolymerizing acrylonitrile and styrene with butadiene blended in the resin has an island-sea structure dotted like islands in a sea of ​​AS, and this graft rubber acts as a foam nucleating agent. It has been confirmed that the foam cells are smaller with PC / ABS than with PC alone. This is because the specific heat of each polymer is different, and minute contractions occur at the interface and boundary regions, resulting in the action and effect of the foam nucleating agent. The above foam nucleating agents can be used alone, or two or more types can be mixed together as necessary.

[0046] A foaming agent useful for foam molding of PC resin is a gas such as nitrogen gas or carbon dioxide gas that is injected into the heating barrel during metering to impart foamability to the plasticized and melted molten resin in the heating barrel. Similarly to the gas, water is introduced into the heating barrel and vaporized by the heat (thermal energy, temperature) of the heating barrel and / or the heat (thermal energy, temperature) of the molten resin that has been heated and melted, and then finely dispersed in the molten resin in the heating barrel to impart foamability. As mentioned above, foam nucleating agents can be used alone or in combination of two or more types.

[0047] In the case of PC resin, the foam nucleating agent may act as a catalyst to accelerate the decomposition of PC resin, or the foam nucleating agent itself may decompose the PC resin. In particular, when water is used to foam PC resin, a substance that does not hydrolyze PC resin is selected.

[0048] Examples of useful foam nucleating agents in the foam molding of PC resin include light diffusing agents such as silver oxide, aluminum oxide, silicon dioxide, and silicon carbide, which do not decompose PC and do not cause a decrease in physical properties. As a result of extensive research by the inventors, the content ratio of the components in the foam nucleating agent of the present invention is preferably 40 to 60 parts by weight of aluminum oxide, 20 to 40 parts by weight of silver oxide, 1 to 10 parts by weight of silicon dioxide, and 1 to 10 parts by weight of silicon carbide. The particle size of the components other than silver oxide is preferably 30 μm or less in order to be blended with PC resin. If it exceeds 30 μm, it cannot be uniformly dispersed in the resin and sufficient light diffusing effect cannot be obtained, which is not preferable. More preferably, it is 100 nm to 10 μm. These components may be commercially available or may be synthesized to any particle size. Also, those with a large particle size may be crushed. The synthesis method is not particularly limited.

[0049] Silver oxide is useful as a foam nucleating agent for PC resins, and promising alternatives to silver oxide include Cu2O, ZnO, Al2O3, MgO, TiO2, ZrO2, V2O3, V2O5, tungsten oxide, FeO, Fe2O3, manganese oxide, chromium oxide, cobalt oxide, nickel oxide, In oxide, indium (In) tin (Ti) oxide, germanium oxide, tin oxide, lead oxide, corundum, carborundum, Al2O3·MgO (spinel), WC (tungsten carbide), TiN (titanium nitride), and CrN (chromium nitride).

[0050] On the other hand, for example, carbonates such as calcium carbonate (Ca), magnesium carbonate (Mg), and barium carbonate (Ba), sulfates such as calcium sulfate and barium sulfate, and alkali metal salts of organic acids, especially monosodium dihydrogen citrate and monopotassium dihydrogen citrate, act as effective foam nucleating agents, but there is concern about the decomposition of PC. Helical D (a calcium-containing inorganic filler made by Shiraishi Calcium) also acts as a foam nucleating agent. The above foaming assistants such as zinc stearate, barium stearate, and metal soaps also act as foam nucleating agents. Glass fiber, glass beads, carbon fiber, carbon powders such as Ketjen Black and Acetylene Black, and carbon nanotubes (CNTs) also act as foam nucleating agents. Metal powders are also acceptable. Nanomaterials from Adachi Shinsangyo Co., Ltd. can also be used as foam nucleating agents. Resin additives, such as pigments, also act as foam nucleating agents.

[0051] {Particle size of foam nucleating agent (particle size)} If the particle size of the foam nucleating agent is fine, it can be uniformly dispersed in the resin and the size of the foam cells can be made uniform. Although it depends on the foam nucleating agent used, it is generally 250 μm (micrometer, micron) or less, preferably 100 μm or less, and considering uniform dispersion, 50 μm or less is preferable. Even finer particles of 100 nm (nanometer) to 10 μm are better.

[0052] (Use of foam nucleating agents) The foam nucleating agent used may be one type (single), or two or more types may be mixed together (composite use). The particle size may also be the same, or even if a single type is used, different particle sizes may be used. When using multiple types, the particle sizes of the foam nucleating agents may be the same or different.

[0053] (Master batch of foam nucleating agent) Useful foam nucleating agents for use in foam molding of PC resins include metal oxides and metal carbides. These foam nucleating agents are mixed (dispersed) in the resin before use, but if the foaming agent is liquid, it is mixed with the liquid before use. A foam nucleating agent with a high concentration (content of foam nucleating agent) may be produced in the pellets of the resin to be foamed and used as a master batch. When there are several types of foam nucleating agents, each of them (meaning one type of substance in this invention) may be made into a master batch of foam nucleating agent, and the master batch of each foam nucleating agent may be mixed with the pellets of the resin to be foamed and used. A master batch of foam nucleating agent may be produced by heating and melting and kneading (for example, melting and kneading using an extruder, or pelletizing using a pelletizer), but a master batch of foam nucleating agent can also be produced by supporting it on the surface of the pellets of the resin to be foamed as described in PCT / JP2020 / 15536.

[0054] "Mix ratio" is expressed as the ratio of the weight (wt.) or volume (vol.) of the foam nucleating agent master batch to the weight or volume of the resin to be molded, assuming that the weight (wt.) or volume (vol.) of the foam nucleating agent master batch is 1. It is expressed as the ratio (weight ratio) of the foam nucleating agent master batch contained in the resin to be foam molded (weight is generally used). For example, it is 2 wt. (weight)% or 2 vol. (volume, volume)% relative to the resin. It is expressed as 2:100 (or 1:50, or 1 / 50), or 2 wt.%, 2 vol.%, etc. When a liquid foaming agent is used, it is expressed as the volume (vol.) relative to the weight (wt.) or volume of the resin.

[0055] (Amount of foam nucleating agent added) The amount of foaming nucleating agent added can be within the range that does not affect the physical properties of the resin and allows for acceptable deterioration of the physical properties. The amount added varies depending on the resin to be foamed and also on the foaming gas that imparts foaming (for example, nitrogen gas or carbon dioxide gas may be used alone, or a composite gas may be made by mixing the various foaming gases, such as nitrogen gas, carbon monoxide, carbon dioxide gas, and water vapor). The amount of foam nucleating agent to be added to the resin to be foamed is 0.001 to 10 parts by weight per 100 parts by weight of resin. If the amount of foam nucleating agent is less than 0.001 part by weight, the particle size of the foam cells will be large. On the other hand, if the amount of foam nucleating agent added is large, the foam cells will become finer and the foaming power will be strong, so in order to eliminate the swirl marks that occur on the surface of the GCP and obtain a foam molded product with a smooth surface and a beautiful appearance, the type and pressure of the gas used (the inventor uses air at a pressure of 1.4 MPa, taking into consideration economical reasons and ease of foam molding) is generally changed. It is possible to suppress swirl marks by increasing the pressure of the GCP, and if carbon dioxide gas is used instead of air, the carbon dioxide gas will dissolve into the flow front of the molten resin to which foaming properties have been added and the swirl marks will be reduced. For reference, GCP using carbon dioxide gas will produce a beautiful surface even in the case of non-foaming resin. Composite materials such as glass fiber also have the effect of sinking the glass fiber.

[0056] [Polycarbonate resin, polycarbonate ester {polycarbonate (PC)}] The PC used in the present invention will be described. PC is a polycarbonate produced from bisphenol A and phosgene or di(di)phenyl carbonate. When carbonyl chloride is used, it is polymerized by interfacial condensation polymerization. When diphenyl carbonate is used, it is synthesized by polymerization by ester exchange. There is no particular limitation on PC, and any known resin can be used. For example, a resin obtained by reacting an aromatic dihydroxy compound with phosgene or a carbonic acid diester by a melting method or a solution method can be used. Representative examples of aromatic dihydroxy compounds include 2,2-bis(4-hydroxyphenyl)propane (=bisphenol A), 1,1-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, bis(4-hydroxyphenyl)sulfide, and bis(4-hydroxyphenyl)sulfone. Among these, bisphenol A is particularly preferred and widely used. In the present invention, in addition to bisphenol A-based PC, which is a widely used PC, it is also possible to use PC produced using other dihydric phenols.

[0057] Furthermore, trivalent or higher phenolic compounds such as those shown below may be used in combination. Trivalent or higher phenolic compounds include phloroglucin, 4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)-heptene, 2,4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)-heptane, 1,3,5-tri-(4-hydroxyphenyl)-benzene, 1,1,1-tri-(4-hydroxyphenyl)-ethane, and 2,2-bis-[4,4-(4,4-dihydroxydiphenyl)-cyclohexyl]-propane.

[0058] The viscosity average molecular weight of the PC used in the present invention is 1,000 to 100,000. More preferably, it is 10,000 to 50,000. When producing such PC, a molecular weight regulator, a catalyst, etc. can be used as necessary. The PC resin may be used alone or in a suitable mixture of two or more kinds.

[0059] (Regarding the production of PC resin compositions) The method for producing the PC resin composition containing the foam nucleating agent of the present invention is not particularly limited, but a preferred method for producing the resin composition of the present invention is a method of melt-kneading each component using a multi-screw extruder such as a twin-screw extruder. A representative example of a twin-screw extruder is ZSK (trade name, manufactured by Werner and Pfleiderer). Specific examples of similar types include TEX {trade name, manufactured by Japan Steel Works, Ltd.}, TEM {trade name, manufactured by Toshiba Machine Co., Ltd.}, and KTX {trade name, manufactured by Kobe Steel, Ltd.}. Other specific examples include melt-kneaders such as FCM (trade name, manufactured by Farrel), Ko-Kneader (trade name, manufactured by Buss), and DSM (trade name, manufactured by Krauss-Maffei).

[0060] (Purpose and meaning of foaming PC resin) PC is a resin whose impact strength is highly dependent on thickness. For example, the impact strength of solid (general, general) molded products with a thickness of 5mm or 6mm is lower than that of ABS. However, if the thickness is reduced to 1mm or 2mm, the impact strength becomes extremely high. It has been confirmed that if 0.2mm PC is laminated, it will not break even if a large impact is applied. If this is the case, it is possible to obtain a PC foam structure with sufficient impact strength by foaming it using water, which does not affect the physical properties of PC, as a foaming agent, making an expanded core such as a mold back or core back, increasing the foaming ratio and forming thin PC foam cells on the surface and inside. This is the purpose of the foaming molding of PC and resins mainly composed of PC described in this invention. PC is often used in polymer alloys with other resins, such as ABS, but in this case, PC also has a thin layer in the ABS, so it is possible to use water as a foaming agent for foaming molding of PC / ABS, PC / PS, PC / HIPS, etc.

[0061] (Method of increasing the expansion ratio of PC resin) Water is used as the foaming agent, and the resin that has been given foaming properties in the heating cylinder of the molding machine is filled into the cavity. After filling, the mold is moved back a predetermined distance (generally the movable mold is moved back. In other words, the PL is opened a predetermined distance). The detailed process is shown below. The mold is closed, and the foamable resin is filled into the cavity. The mold is opened a predetermined distance at the same time as filling, or with a slight delay after filling. At this time, the molded product expands due to the foaming force of the foamable resin. In addition, when the inside is made hollow (inner GCP) {in hollow molding using foamable resin, high-pressure nitrogen gas or the like is injected from the nozzle of the molding machine, or / and from the runner, or / and directly into the molded product, and the inside is expanded by the force of the fluid} {especially in the core-back shown in Figures 11, 12, 13, and 14, the PL is vertically cut off, so there is little flash even if the mold is opened widely. However, when the expansion ratio is extremely increased to 2, 5, or 10 times, the foaming power alone is not enough to transfer the foam to the mold, and if the molded product is cored back as it is, it will separate from the mold, and as a result, the mold reproducibility will decrease. As a result, a foamed molded product with a high expansion ratio cannot be obtained. In the foam molding using Aotar GCP, the mold reproducibility is further decreased, so a foamed molded product with a high expansion ratio and a smooth and beautiful surface cannot be obtained. To solve this problem, the inventor also performed hollow molding (; inner GCP) using a foamable resin and confirmed that sufficient mold reproducibility was obtained. It was also confirmed that a foamed molded product with a high expansion ratio and a beautiful surface can be obtained by using an outer GCP to perform hollow molding (; inner GCP) on a foamable resin, followed by mold backing and core backing. Once cooling and solidification is complete, if a pressurized fluid (also called a "high pressure fluid" or "compressed fluid"; generally, gas compressed to above atmospheric pressure is used, but liquid is also fine. In the case of gas, the main ones are air, nitrogen, and carbon dioxide, either alone or in combination. In the case of liquid, the main one is water, but it can also be used at higher temperatures such as 40℃, 50℃, 90℃, and even 100℃ because the pressure is so high that it can remain liquid) is injected into the molded product, the pressurized fluid is vented and the pressure is reduced to a level where the internal pressure will not cause the product to expand or burst, and the mold is then opened and the foam molded product is removed.At this time, in a three-plate mold, if the PL is opened a certain distance beforehand, the stripper plate will not open even if the PL is opened as is, and the spool runner cannot be removed; therefore, it is necessary to incorporate a mechanism in the mold that will open the stripper plate later, even if the PL is opened first. Furthermore, the software that controls this mold back and core back can be implemented by exchanging signals with the molding machine using an external sequencer (PLC, a controller box using a PLC), but it is also possible to add (write) software that performs these operations to a PLC (a PLC with programs written into it that control opening and closing the mold, injection, etc.) built into the molding machine.

[0062] The method for feeding the foam nucleating agent and the PC resin of the present invention to the extruder is not particularly limited, but the following method is a typical example. (1) A method in which the foam nucleating agent of the present invention and a PC resin are supplied independently to an extruder. (2) A method in which the foam nucleating agent of the present invention and the PC resin additive are premixed in a mixer such as a super mixer, and then the mixture is fed to an extruder.

[0063] The method is not limited to the above, and a resin may be produced after mixing an arbitrary amount of the foam nucleating agent with the raw material PC. The method for producing the PC resin composition is not limited at all. The PC resin composition containing the foam nucleating agent of the present invention can also be used for foam molding in the form of various profile extrusion molded products, sheets, films, etc. by extrusion molding. Furthermore, it can be molded into a heat shrink tube by applying a specific stretching operation. Furthermore, it can be molded into a molded product by rotational molding or blow molding. It can also be molded from flame-retardant PC resin compositions (resins made flame-retardant by adding flame retardants and flame retardant assistants) and resins with added minerals such as glass fiber to increase rigidity. These molded products can also be subjected to various surface treatments such as painting and plating.

[0064] Among PC-based resins, polymer alloys and polymer blends that contain PC as the main component include PC / PET (polyethylene terephthalate), PC / PBT (polybutylene terephthalate), PC / ABS (acrylic-nitrile-styrene graft terpolymer in which acrylic-nitrile and styrene are graft copolymerized onto butadiene, and AS (copolymer of acrylic-nitrile and styrene)), PC / AES, PC / AAS, PC / ASA, PC / PS (polystyrene), PC / PP (polypropylene, polymethylvinyl), PC / PE (polyethylene, polyvinyl hydrogen), PC / vinyl chloride (polyvinyl chloride, PVC), and PC / PPO. In foam molding, if the foam nucleating agent is not selected correctly, the original physical properties of PC will not be exhibited. Water is a useful blowing agent for foam molding of PC resins, but when PET or PBT is included in a polymer alloy or polymer blend mainly composed of PC, the ester resins such as PET decompose and the physical properties decrease significantly. In the case of polyamide (PA), hydrolysis hardly occurs at all.

[0065] "Compatibility" refers to the property of thermoplastic resins to mix at the molecular level when each resin is heated and melted; for example, AS is compatible with ABS, and PS (polystyrene) and HIPS (high impact polystyrene) are compatible with PPO (polyphenylene oxide) and PPE (polyphenylene ether). In this invention, PPO and PPE are treated as the same substance and referred to as "PPO." PPO that is modified or denatured (mixed to form a blended polymer or polymer alloy) with HIPS and / or PS, as well as PP, ABS, and PA, is called modified-PPO, modified-PPO, or m-PPO.

[0066] "Compatibility" refers to a situation where one resin is not compatible with the other and is dispersed in the other, forming an island structure or other structure. For example, rubber B in ABS {a polymer (polymer) in which butadiene rubber is graft-copolymerized with acrylonitrile (vinyl cyanide) and styrene (vinyl phenylate)} shows compatibility with AS. When they are compatible, there is no or only a small decrease in physical properties.

[0067] {Compatibilizer} When manufacturing polymer alloys and polymer blends, such as PC / PET, PC / PBT, PC / AS, PC / ABS, PC / PS, and PC / HIPS, which have PC as the main component, a compatibilizer is used as necessary. Examples of compatibilizers used for these purposes include those sold by Nippon Oil & Fats. If the amount of compatibilizer added is small, the resin will not be compatible (miscible) enough and the physical and chemical properties of the resin will not be fully exhibited. If too much is added, the physical properties will decrease significantly, so it is desirable to add an amount that has little effect on the physical properties relative to the weight of the PC.

[0068] (Suitable for painting) In the case of PC resin molded products, if the internal stress (internal distortion) is high, the paint solvent (thinner) will cause microcracks and the high impact strength of PC will not be exhibited. In the foam molding of this invention, the molding is a cut-off molding that does not use a dwell pressure as in the case of injection molding, so there is little internal stress. Even if painting is applied in this state, there will be less deterioration in physical properties due to cracking than in molded products with high internal stress caused by high dwell pressure. If the product is further annealed for about 2 hours to remove the internal stress, the deterioration in physical properties (such as cracking) due to microcracks will be further reduced.

[0069] (Example of foam molding of PC resin) When performing foam molding of PC-based resins, as is clear from Comparative Example 1 (foaming agent used was sodium bicarbonate), Comparative Example 2 (foaming agent used was ADCA), and Comparative Example 3 (foaming agent used was ethanol) described below, the properties of PC (high impact strength = does not break easily) are not exhibited at all in the foam molding of PC. However, as shown in Example 1, it was confirmed that if water (chemical name is "hydrogen oxide, dihydrogen monoxide", chemical formula is "H2O") is used as the foaming agent, the deterioration of the physical properties of PC is small.

[0070] (Outer GCP) Using water as the foaming agent, water was injected into the heating barrel of the injection molding machine through the liquid injection device and the injection port on the heating barrel shown in Fig. 1, Fig. 4, and Fig. 5 of PCT / JP2015 / 062611 to perform foam molding. Swirl marks due to the water foaming agent were generated on the surface of the foam molded product. When GCP was performed using 1.4 MPa air and the nozzle shown in Fig. 20 to Fig. 22 of PCT / JP2015 / 062611, the sealed mold for GCP shown in Fig. 23 and Fig. 25, and the GCP device shown in Fig. 24, it was confirmed that it is possible to produce foam molded products with no swirl marks on the surface, a clean and smooth skin layer, and a fine foam layer inside.

[0071] (Undercut Treatment) When the molded product has an undercut (protruding part) shape as shown in Figures 17 and 18, a mechanical slide using a slide core (outer slide core method), tilted core method (tilt pin), hydraulics, pneumatics, rack and pinion, ball screw, etc. is used. In Figure 17, reference number 57 indicates the undercut part, and the arrow at reference number 58 indicates the slide direction. In this case, an angular pin is used, and by linking the opening and closing of the mold with the opening and closing of the slide, it is possible to process the undercut (processing molded products with undercut shapes). Since the amount of movement of the slide is determined by the angle of the angular pin, in some cases a new part such as a slide stopper that stops the slide from going down too far is installed. If the undercut portion indicated by reference number 57 (shown as a hole in Fig. 17) is long, a slide core using hydraulics or the like is used. Reference number 55 indicates the cross section of the product (cross section of the cavity), and 61 is the PL of the mold (the parting surface, parting portion, the surface where the movable side mold and the fixed side mold come together, the space defined by the joining of the fixed side mold and the movable side mold is the "cavity").

[0072] In the case of Fig. 18, the undercut treatment of reference number 59 is mainly performed by the inclined core method. Reference number 60 indicates the direction of the slide. Reference number 56 indicates the cross section of the product, and reference number 61 is the PL of the mold.

[0073] (Sealing mold) First, we will explain the structure of the sealing mold for GCP, which is an effective means of eliminating the swirl marks that occur on the surface during foam molding used in this invention and obtaining foam molded products with a smooth surface. There are two types of sealing mold structures: one that surrounds the ejector mechanism with a spacer block (mold structure), and one that seals each ejector pin with an L-shaped, U-shaped weighted O-ring, or a U-shaped (concave) O-ring (mold structure). Figure 19 shows the structure of a sealing mold using an ejector box, in which the spacer block (74) is integrated into a single structure shaped like the Japanese katakana character "ro" and houses and seals the ejector mechanism. Reference number 62 is a spool bush, which is sealed with an O-ring (64). Reference number 63 is a mounting plate on the fixed (cavity) side, and an O-ring 65 is installed between the mounting plate and the fixed mold plate (104) to seal. Reference number 89 is a fixed side insert that forms a cavity, reference number 61 is a PL, and an O-ring (69) is placed (installed) on the PL. Reference numbers 55 and 56 are cavities that are filled with molten resin. Reference number 70 is a movable (core) mold plate, in which an insert (92) is installed. The insert is fixed by bolts (not shown) or the like. The pressurized air and pressurized fluid in the cavity also enter and exit through the gap (the mating surface) of the insert (92). Reference number 87 is a receiving plate. Reference number 72 is an O-ring that seals between the movable mold plate (reference number 70) and reference number 87, reference number 73 is an O-ring that seals the gap between reference number 87 and reference number 74 (a spacer block processed into the shape of the Japanese katakana character "ロ" to enclose and seal the ejector mechanism), which completes reference number 75, an ejector box structure (a mold structure that encloses the ejector mechanism in a space for sealing purposes). Since the ejector pins are sealed by the ejector box, there is no need to seal each of the ejector pins (reference number 67). Reference number 76 is an ejector plate (upper) that fixes the ejector pins, and reference number 77 is an ejector plate (lower) that fixes the ejector pins. Reference number 80 is a mounting plate on the movable side, and reference number 79 is an O-ring installed in the gap between reference number 80 and reference number 74. Reference number 82 is an ejector rod hole, and an O-ring indicated by reference number 81 is assembled at the bottom of reference number 77 to seal when the mold is closed and the ejector plate is moved back by a return pin (not shown) or the like.

[0074] The O-rings with numbers 64, 65, 69, 72, 73, 79, and 81 are commercially available and are made of NBR (nitrile butadiene rubber), silicone rubber, urethane rubber, etc. These O-rings are used by carving a groove into which they are fitted, but there is a risk that the surfaces fixing the O-rings with numbers 69 and 81 will come apart when the mold is opened and the molded product is extruded, resulting in the O-ring coming out of the groove. Therefore, the inventor has devised a tapered end mill to make the grooves with numbers 69 and 81 into dovetail grooves (shapes in which the top is narrower than the bottom in cross section) so that the O-rings will not come out of the groove even if the plate comes apart.

[0075] Next, the gas circuit for pressurizing the inside of the mold {mainly air compressed to atmospheric pressure or higher is used, but in some cases nitrogen gas, carbon dioxide gas, or a mixture of these gases is used.} is explained. Reference number 88 is a circuit that puts compressed air (gas, pressurized fluid in a broad sense) into the bottom of the fixed side insert, and pressurizes the inside of the cavities 55, 56 from the gap (not shown) between the fixed side insert (reference number 89) and reference number 104 (fixed side mold plate), and the inventor calls this L3 (pressurized air into the cavity from the fixed side). During filling of the cavity with foamable resin or non-foamable resin, after filling is completed, and after a certain time has passed since filling is completed, the compressed air in the mold is exhausted to the atmosphere through the same circuit. Reference number 66 is an arrow that indicates the flow of compressed air in the mold, and in order to show that the pressurization and exhaustion in the mold are performed through the same circuit, both the beginning (start point) and the end (end point) are illustrated as arrows. Reference number 90 is a circuit that pressurizes the cavity 55 and reference number 56 from PL, and reference number 91 indicates the flow direction of the pressurized fluid (for example, gas). Reference numbers 90 and 91 are called L2 and are pressurized fluid (for example, gas) circuits that pressurize the cavity from PL and exhaust it. Reference number 95 is a compressed air fluid (gas) circuit that pressurizes the inside of the ejector box of reference number 75 by drilling a hole in reference number 74 and exhausts it. Reference number 96 is an arrow (the start point and the end point are also indicated by arrows, as with L3) that indicates the flow of compressed air fluid (gas) in the ejector box. When the inside of the ejector box is compressed, for example, gas (compressed air) in the ejector box pressurizes the inside of the cavity (reference numbers 55 and 56) through the gaps of the ejector pins and the gaps of the insert, and in the present invention, this is called L1. When the ejector box is vented after the molten resin is filled, the pressure inside the ejector box decreases, and as a result, the pressure inside the cavity decreases.

[0076] The ejector box structure has a simple sealing method and a high sealing effect, but the ejector box is larger in volume than the cavity, and a large amount of air is required to pressurize a mold sealed with the ejector box structure. Moreover, it takes time to pressurize the mold, which results in economic problems such as the extra air costs and time required for pressurization, resulting in a longer molding cycle.

[0077] FIG. 20 explains a means for sealing the ejector pin to solve the problem of FIG. 19. The difference between FIG. 19 and FIG. 20 is that the ejector mechanism is enclosed by the "R" shape of reference number 74, but the ejector pin is sealed by the weighted O-ring of reference number 103, so the spacer block of reference number 105 can be of a normal shape. As a result, the O-rings of reference numbers 79 and 81 are not necessary. Reference number 93 pressurizes the cavities 55 and 56 through the gap between the bottom of the movable insert and the ejector pin. Reference number 94 is an arrow indicating the flow of the compressed air and exhaust fluid (gas), and corresponds to L1 in FIG. 19. Reference number 101 is a seal plate into which reference number 103 is fitted and fixed. A groove may be dug directly into the seal plate 101 to insert reference number 103, or the seal plate may be inserted to insert reference number 103. The seal for the inclined pin shown in Figure 24 requires that the weighted O-ring 103 be installed parallel to the axis of the inclined pin, so it is better to use a nested O-ring. Number 102 is an O-ring installed in the gap between the receiving plate 87 and the seal plate 101. The movable side is very different, but the differences between the PL and fixed side seals and the like in Figures 19 and 20 are not great.

[0078] Figure 21 shows the mold structure when processing the undercut shape of reference number 57 shown in Figure 17 with a slide core. Reference number 69 is the O-ring of PL, and reference number 97 is the guide pin or guide post, which is provided outside of reference number 69. Reference number 98 is a fluid (gas) circuit provided in PL to pressurize the insides of reference numbers 55 and 56, reference number 184 is an outlet for blowing out compressed air from the compressed air circuit of reference number 90L2, which is connected to reference number 98 and also to reference number 90 as shown in Figure 22. Reference number 99 is an arrow showing the flow of compressed air and exhaust air of reference number 98. Reference number 68 is the slide core, and reference number 78 is a hole into which the angular pin fits. The slide core of reference number 68 must be placed inside the O-ring of PL of reference number 69 in order to be sealed. The mating surface of the slide (PL surface of the slide) also needs to be sealed (not shown) with an O-ring on the outside of the product shape in the same way as reference number 69. FIG. 21 is a front view of the cavity in FIG. 19 and FIG.

[0079] Figure 22 is a cross-sectional view of the cavity in Figures 19 and 20, where reference number 184 is the L2 circuit, reference number 98 is the L2 fluid (gas) circuit (groove) provided in the PL of the mold, and the inventor has set the cross-sectional shape to, for example, a width (width, width, width) of about 5 mm to 10 mm and a depth of about 1 mm to 3 mm. Reference number 100 is a vent that pressurizes and exhausts air to the cavities 55 and 56, and is not provided around the entire circumference, but is provided at regular intervals {pitch intervals of 20 mm to 50 mm)} like a comb shape. The width is about 5 mm to 10 mm, and the depth varies depending on the molten resin, but for resins with high fluidity such as PP, it is about 0.03 mm in consideration of the risk of burrs, for ABS it is about 0.05 mm to 0.1 mm, and for modified PPO, PC, etc., the fluidity is not high, so the risk of burrs is low and it is acceptable to have a depth of 0.1 mm or more.

[0080] FIG. 23 shows a means (mold structure) for treating the undercut of reference number 59. In the case of such a shape, an inclined core is used. Reference number 107 is an inclined core. The movable side including the movable side mold plate of reference number 70 moves back, and the PL of reference number 61 is opened. When the ejector rod (not shown) provided in the molding machine is pushed, the ejector plate (ejector plate) composed of reference numbers 77 and 78 is pushed forward, and the ejector pin of reference number 70 and the shaft of reference number 108 are also pushed out as shown by the arrows (reference numbers 109 and 110). As a result, the resin filled in reference number 56 (a molded product that has been cooled and solidified) is pushed out. The inclined core of reference number 107 moves in the direction of the arrow of reference number 111 (perpendicular to the opening and closing direction of the mold in FIG. 23). The molded product moves relative to the inclined core 107 as indicated by reference numeral 112, and the undercut indicated by reference numeral 59 comes out of the mold, allowing the molded product to be removed. In FIG. 23, the load type O-rings 103 and 106 are arranged facing the cavity, but if they are arranged in the opposite direction, a mold structure can be created in which the cavity is made into a vacuum (meaning a reduced pressure below atmospheric pressure) for molding.

[0081] FIG. 24 shows that when there are multiple inclined cores that cross closely with each other, it is difficult for the weighted O-ring to seal adequately with only one seal plate. In such a case, sealing is possible by using multiple seal plates (FIG. 24 shows the use of two plates, reference numbers 101 and 116).

[0082] For the outer GCP, "pressurizing" or "pressurizing" the inside of the mold (cavity). "Pressurizing the GCP", "pressurizing the GCP", and "applying the GCP" are synonymous with using gas to increase the pressure inside the mold before filling it with molten resin. Also, "exhausting". "Exhausting the GCP" is a synonym for venting the gas that has pressurized the inside of the mold into the atmosphere during or after filling with molten resin, lowering the pressure inside the mold and causing foaming. Sometimes a vacuum is used.

[0083] (Hollow molding) When using a pressurized fluid injection pin (Figure 29) consisting of an ejector pin (Figure 27) and an ejector sleeve pin (Figure 28) to perform hollow molding of non-foaming resin, the problem is the speed of exhausting the pressurized fluid from inside the molded product. Since the injection is originally done with high pressure into the molten resin in the cavity, the injection pressure is constant and the injection speed is not a big problem. In the case of exhaust, the pressurized fluid in the hollow part must be exhausted to reference number 122 through a narrow gap (about 0.01mm to 0.08mm) as shown in Figures 27, 28, and 29. As the exhaust progresses, the pressure in the hollow part of the molded product decreases, making it difficult to exhaust, and the exhaust speed slows down. If the pressurized fluid in the hollow part is not exhausted sufficiently and completely and the mold is opened, the residual pressure inside the hollow part will cause the molded product to swell and burst. To solve this problem, a mold with an ejector plate (B) consisting of reference numbers 117 and 118 (Figure 25) is used. Before the resin is filled, the ejector plate (B) is advanced by a stepped ejector rod, and non-foaming resin and foaming resin are filled. During the resin filling process and after filling is completed, pressurized fluid is injected from reference number 121, and the inside of the molded product is hollowed out through the pressurized fluid injection pin at reference number 120 (assembled in Figures 27 and 28). After hollowing out, the exhaust valve of the hollow molding device is opened to exhaust the pressurized fluid that was put into the hollow, and once the pressure has dropped, the ejector plate (B) is moved backwards {; this is possible by lowering the ejector rod. Springs, gas springs, etc. are installed in the ejector plate (B), and when the ejector rod is lowered, the force of the springs, etc. forces the ejector plate (B) down.}, the tip of the pressurized fluid injection pin 120 separates from the boss 123 (provided for the purpose of directing the pressurized fluid into the molten resin) that surrounds the tip of the pressurized fluid injection pin of the molded product, creating a space, which is then exhausted all at once. In Figure 25, the ejector pin 67 penetrates the ejector plate (B).

[0084] This is an effective method for foam moldings with high expansion ratios using foamable resins, and for thermoplastic elastomers with low resin rigidity. When molding foam moldings with expansion ratios of 2x, 3x, 5x, or even higher, the cavity is filled with foamable resin that has been given foaming properties using a gas, liquid, or solid foaming agent (either alone or in combination), making the inside hollow. With pressure still applied to the hollow, the mold is returned and the core is returned, venting the pressurized fluid in the hollow, and the pressurized fluid pressurizing pin is retracted {the ejector plate (B) is retracted.} The pressure in the hollow is suddenly reduced, and foaming begins toward the inside. In the case of molded back as shown in Figures 11 and 12, the foaming ratio must be about 2 times or there is a risk of flashing. In the case of core back as shown in Figures 13 and 14, there is no risk of flashing. An outer GCP may also be used.

[0085] (Method of avoiding defects such as swelling and bursting during blow molding) The filling of the cavity with the molten resin starts (the injection start signal is output), and during the filling, or immediately after the filling is completed, or after a predetermined delay time has passed, the injection valve of the blow molding device is opened to start the hollowing of the molten resin. After the predetermined time for opening the injection valve (called the "injection time" in this invention) is completed, the pressurized fluid is trapped in the hollow. This is called the "retention time" in this invention. After the retention time is completed, the exhaust valve of the blow molding device is opened and the pressurized fluid in the hollow is exhausted to the atmosphere. After the time is up on a timer that is started (triggered) by the start of exhaust, the ejector plate (B) is moved backward until no swelling or burst occurs due to the pressurized fluid in the hollow, and after cooling and solidification are completed, the mold is opened and the molded product is removed. The mold in Figure 25 shows a sealed mold of GCP specifications, but in the case of blow molding using non-foaming resin, sealing is not necessary, and there is no need to seal the PL, etc. as shown in Figure 36. Of course, if the mold in Figure 25 is used without using GCP, the function of the mold will be the same as that in Figure 36.

[0086] (Compressed Air Molding) When performing mold backing and core backing, the mold release reproducibility decreases when separating from the mold at that stage. Therefore, pressurize from the inside (by means of hollow molding) and perform mold backing and core backing in a state where it is sufficiently adhered to the mold. Separately, a non-foamed resin or a foamed resin with high mold reproducibility can be obtained by using a means of injecting a pressurized fluid into the gap between the molten resin and the mold and performing mold backing and core backing while applying pressure to the opposite side of the fluid pressurized surface with the pressure of the pressurized fluid. Note that hollow molding and pressure air molding can be used in combination. In this case, there are cases where the pressure of the pressurized fluid for forming hollow molding (referred to as "H pressure" in the present invention) and the pressure of the pressurized fluid for performing pressure air molding (referred to as "P pressure" in the present invention) are such that P pressure > H pressure, P pressure = H pressure, and P pressure < H pressure, and the size of the hollow part formation changes in each case. When using this combination of hollow molding and pressure air molding, it becomes possible to control the size of the hollow part in a PP hollow molded product that was difficult with only hollow molding.

[0087] (Mold structure for pressure air molding) Figure 26 shows the structure of the mold used in compressed air molding. Reference number 125 is a pressurized fluid pressurizing pin (Figure 32), which is made by additional processing of the ejector pin (Figure 30) and the ejector sleeve (Figure 31). The pressurized fluid pressurizing pin is installed between the ejectors because the pressure used is high. It is assumed that the strength of the ejector and the strength of the bolts assembling the ejector plate will not be enough if pressurized fluid is injected, so the inventor installed a plate at reference number 133 on the movable side mounting plate at reference number 80, and fixed with sufficient strength by pressing it down with the die plate (not shown) of the molding machine and the spacer block 105, so that it can withstand the pressure of the pressurized fluid. Reference number 127 is a load type O-ring that seals the gap between reference number 125 and reference number 127. Reference number 128 is a seal plate for installing (fixing) reference number 127, and an O-ring at reference number 102 is installed between reference number 87 and reference number 101 as necessary. Number 126 (also an additionally processed part of the ejector sleeve) is placed in number 129 ejector plate (upper) and number 130 ejector plate (lower). The ejector plate (C) consisting of numbers 129 and 130 moves with the ejector rod as shown by the arrow of number 130. Before the resin is filled, the ejector plate (C) is in the forward position. When the resin is filled into numbers 55 and 56 and the ejector plate (C) is moved backward immediately after filling is completed or after a short delay, number 126 also moves backward, creating a small space in number 135. Pressurized fluid is poured into this space from number 132, and the pressurized fluid reaches number 135 through the gap between the outer tube and core (inner core) of number 125, enters the gap between the resin and the mold, and pressurizes the resin with the pressure of the pressurized fluid. The ejector plate (C) is moved backwards to create a space, disperse the pressure, and fill the resin so that it does not become hollow, as mentioned above. If the resin does not become hollow due to compressed air molding, this mechanism does not need to be provided. Although not shown in the figure, the tip of reference number 135, and if necessary, the surrounding area, can also be embossed on the surface where the compressed air is applied, so that the resin does not become hollow, but enters the gap between the resin and the mold, and the embossing creates a wedge effect. The pressurized fluid equipment used for pressure molding can be the same as that used for blow molding (the same equipment can be used for both blow molding and pressure molding. If this equipment is used to feed pressurized nitrogen gas or carbon dioxide gas (the pressure should be higher than the pressure of the molten resin inside the heater barrel) into the compression zone of the heater barrel instead of into a mold, it is also easy to implement Musel (product name?) or Amottec (product name?); in this case the program can also be written into the molding machine's PLC.)

[0088] (Mold back, core back, outer GCP, inner GCP) In this invention, the GCP in which the inside of the mold is pressurized in advance using the sealed mold shown in Figure 26 is called the outer GCP, and the blow molding using foamable resin is called the inner GCP. When the inner GCP is used, the cavity can be expanded greatly by performing core backing (which is difficult to implement with mold backing due to problems such as burrs and leakage of the pressurized fluid to the outside), and a foam molded product with an even higher expansion ratio can be obtained than with mold backing. When mold-back or core-back is performed using an inner GCP, mold-back or core-back begins at the same time as the pressurized fluid starts to be injected into the molten resin, or after the injection has started and a certain time has elapsed, or when the injection valve is closed and the hollow molding (in this case, the inner GCP) program reaches the hold time, or during the hold time, or when the hold time is completed and the exhaust valve is opened and exhaust begins.

[0089] (GCP) By programming the GCP for the blow molding, mold back, and core back, it is possible to create a foam molded product with a large expansion ratio, a smooth and beautiful surface without swirl marks, and a clean foamed product with a high expansion ratio. The GCP issues a command to the GCP device that the mold is closed, and pressurizes the inside of the mold (the entire mold including the cavity in a sealed mold as shown in Figure 25, etc.). In this pressurized state, the foamable resin that has been given foaming properties is filled into the cavity. During or immediately after filling is complete, or after filling is complete, the pressure valve of the GCP device is closed and the exhaust valve is opened to vent the compressed air inside the mold.

[0090] A separate controller (with a built-in PLC) is set up for the molding programs that operate the blow molding, compressed air molding, mold bag, core bag and GCP devices, and the molding machine receives signals to command the controller and sends them to the controller. It is also common for the controller to output signals to the molding machine and exchange them (meaning that they operate with each other's signals), but the molding machine originally has a PLC (sequencer), so if you write in programs such as blow molding, compressed air molding, GCP, mold bag, core bag and liquid foaming agent, a signal to start metering to the liquid injection device to start injection into the heating barrel, stop liquid injection when the injection time is up or when metering is completed, set the liquid injection position during metering in advance, start liquid injection when the screw passes that position, and stop liquid injection when the screw passes a preset liquid injection stop position, then there is no need to retrieve troublesome signals or use an external controller. It is also possible to write a program to seal the hopper with nitrogen (a means of injecting nitrogen gas into the hopper to prevent discoloration and burning), or to start injecting nitrogen gas into the hopper when measurement starts and stop the nitrogen gas when measurement stops. Nitrogen gas can also be continuously injected into the hopper by changing the switch on the molding machine screen. It is also possible to perform intermittent injection in relation to measurement, such as starting nitrogen sealing when measurement starts and sealing with nitrogen gas when measurement is completed.

[0091] In the molding method using pressurized fluids exemplified by the pressurized gas and pressurized liquid explained in this invention, when controlling a GCP device, a blow molding device, a compressed air molding device, a liquid injector, etc., there are two cases: when each device is operated by writing a program into a PLC (sequencer) in the control panel of the molding machine, and when these devices are operated by writing a program into a PLC in a controller installed separately outside for the purpose of operating these devices, signals are exchanged between the molding machines, and these devices are operated. Each case will be explained in detail below.

[0092] (Gas and liquid injection) (When writing to the molding machine's PLC) The molding machine software is explained below for injecting gas and / or liquid into the heating barrel to give foaming properties to the molten resin in the plasticization stage. The program written into the molding machine's PLC software first starts metering, and when a certain amount of time has elapsed from 0 seconds (the delay time can be set as desired), the valve (reference number 161) of the externally provided liquid and / or gas injection device (Fig. 35) is opened and the liquid is injected, for example, into the initial location of the compression zone in the heating barrel of the molding machine. The liquid is vaporized by the temperature of the heating barrel and the temperature of the molten resin, and is pressurized and dissolved and finely dispersed in the molten resin in the heating barrel by the back pressure during metering and the pressure applied to the molten resin in the heating barrel. The gas (nitrogen gas, carbon dioxide gas, etc.) is pressurized and dissolved and finely dispersed in the molten resin as it is.

[0093] Injection can be stopped when the screw passes a preset position. Alternatively, the start time for injection can be preset, and the start of injection can be treated as a zero start, and injection can be stopped when the time is up (end). The amount of injection may be constant, but if the screw rotation speed changes, the amount of resin plasticized will naturally change, so the injection amount (plunger pump discharge amount) may be synchronized with the screw rotation speed as necessary.

[0094] (For external controllers) When using an external controller rather than writing a program for injecting gas and / or liquid into the molding machine's PLC, signals are exchanged between the molding machine and the controller. The injection molding machine sends a signal to the external controller that it has started metering. The controller, upon receiving the signal, arbitrarily sets a fixed delay time from 0 seconds, and when the time is up, begins injecting the gas and / or liquid into the heating barrel. When the screw passes a stop position arbitrarily set on the molding machine, it outputs a signal to the controller, and upon receiving that signal, the controller stops injecting the gas and / or liquid. The program is reset by this stop signal.

[0095] In injection control by time control, the controller that receives a signal to start injection has a timer that can be set arbitrarily, sets the arbitrary injection time, and stops the injection when the injection time is up. For synchronization with the screw rotation speed, the screw rotation speed is output as a continuous signal to the controller, and upon receiving this signal, the controller controls the gas and / or liquid injection device to change the injection amount.

[0096] In the case of liquids, which are incompressible substances (volume changes little due to pressure), the injection amount can be easily controlled by changing the speed at which the plunger pump piston is pressed, for example the rotation speed of a rack and pinion motor or servo motor, while in the case of gases, which are compressible substances (volume changes much due to pressure), the injection amount is controlled using an automatically opening and closing needle valve, etc. In some cases, multiple injection machines are used, and the controller is installed with one program for each injection machine so that it can receive signal output and input from the molding machine.

[0097] (Compressed air at GCP) (When writing to the molding machine's PLC) Figure 34 is a schematic diagram showing an overview of GCP measures. Reference number 151 is the air pressure valve, and reference number 154 is the exhaust valve. When writing a GCP program into the molding machine, reference number 151 is opened after an arbitrarily set time has elapsed from 0 seconds upon receiving a mold closing completion signal, and the inside of the sealing mold is pressurized (pre-pressurized) to a pressure equal to or higher than atmospheric pressure. An arbitrarily set timer is used for the time to pressurize the inside of the mold, and after the time is up, the molding machine starts filling the cavity with foamable resin or non-foamable resin. In some cases, the air pressure inside the mold is measured using a pressure sensor, and filling starts when the pre-set pressure is reached.

[0098] (Compressed air at GCP) (For external controllers) When the GCP program is not written in the molding machine's PLC and an external controller is used to control the GCP device shown in Figure 34, the molding machine outputs a mold clamping completion signal to the external controller. Upon receiving this signal, the controller opens the GCP device (reference number 151) and pressurizes the inside of the mold. After the time for pressurizing the inside of the mold, which is preset in the controller, is up, the controller outputs an injection start signal to the molding machine, and upon receiving this signal, the molding machine starts filling the cavity with molten resin. Alternatively, if the controller confirms that a pressure sensor that monitors the compressed air pressure installed in the mold has reached a preset pressure, the controller outputs an injection start signal to the molding machine, and upon receiving this signal, the molding machine starts filling.

[0099] (GCP exhaust) (When writing to the molding machine's PLC) The compressed air in the mold can be exhausted during filling (at any position of the screw), after filling is completed, or after a certain time has passed after filling is completed. In the case of a molding machine, the exhaust valve 154 is opened to exhaust the compressed air in the mold when the screw position is set to the PLC, or after a time set arbitrarily from 0 seconds has passed.

[0100] (GCP exhaust) (For external controllers) When exhausting using an external controller rather than the PLC inside the molding machine, the molding machine outputs an exhaust signal to the controller. For exhausting during filling, an exhaust signal is output to the controller when the screw passes a position that is set arbitrarily, and for exhausting after injection is complete, an injection completion (primary pressure completion or secondary pressure completion) signal is output. Upon receiving this signal, the controller starts an internal timer, and after a set time has elapsed from 0 seconds, the exhaust valve 154 is opened to exhaust air.

[0101] {Mold back, core back} (When writing to the molding machine's PLC) The foaming ratio is increased by retracting the mold (usually the movable mold) a set distance at the start of exhausting compressed air, during exhausting, or after a set time has elapsed from 0 seconds after exhausting is complete. When using the molding machine's PLC, this is performed at the start of exhausting selected, during exhausting, or after a set time has elapsed from 0 seconds after exhausting is complete. When operating with pressure, the mold starts to retract when the pressure gauge installed on the mold reaches a preset pressure (the set exhaust pressure).

[0102] {Mold back, core back} (When using an external controller) When an external controller is used, as soon as exhaust starts, a signal to retract the mold is sent to the molding machine, causing the mold to retract (the mold retracts at the same time as exhaust starts). Or a timer starts when exhaust starts, and when the timer is up, a signal to retract the mold is sent to the molding machine, causing the mold to retract (the mold retracts during exhaust). In some cases, a timer starts when the controller starts exhausting, and when exhaust is sufficiently complete, a signal to retract the mold is sent to the molding machine, causing the mold to retract (the mold retracts after exhaust is complete). It is also possible to have a timer in the molding machine PLC, rather than in the controller. In this case, a signal to start the exhaust timer is output. To monitor the pressure and cause the mold to retract, a signal to retract the mold is sent to the molding machine when the air pressure drops to the set pressure, and the mold is retracted after an arbitrarily set time has elapsed from 0 seconds after receiving that signal.

[0103] The above example shows the case where there is only one GCP device, but if multiple devices are used (L1, L2, L3: L1 = space under the movable insert or space such as the ejector box, L2 = cavity, L3 = space under the fixed insert), prepare the same number of programs for pressurizing and exhausting the air inside the mold, whether in the molding machine's PLC or in the controller. There are also cases where L1, L2, and L3 are exhausted with one GCP device. When pressurizing and exhausting air using a pressure gauge, the main pressure is the cavity pressure, but other pressures are also acceptable. The mold retreat is a means of increasing the volume of the cavity and increasing the foaming ratio.

[0104] (Pressurized fluid injection, retention, and evacuation during blow molding) (When writing to the molding machine's PLC) Hollow molding (including inner GCP) is a molding method in which, using the device shown in Figure 35, gas (such as air, nitrogen gas, carbon dioxide gas, etc.) at atmospheric pressure or higher is injected into the molten resin in the cavity during or after filling of the cavity with foamable or non-foamable resin, for example, using a pressurized fluid injection pin (120), to make the inside hollow, or liquid (such as heated water) pressurized to a high pressure (high pressure) is injected to make the inside hollow. The hollow molding program written into the PLC of the molding machine can be used in two ways: when the screw passes a position arbitrarily set in advance, the pressurized fluid injection valve (161) is opened to inject pressurized fluid (pressurized fluid injection during filling, pressurized fluid injection during filling), or when pressurized fluid is injected immediately after filling is completed or after an arbitrarily set time has elapsed from 0 seconds (pressurized fluid injection after filling is completed). The injection pressure is set using a regulator (165). The injection time is arbitrarily set (called the "injection time"). After the injection time is complete, injection valve 161 closes, and the time for which the pressurized fluid is trapped inside the mold (called the "retention time") is set as desired. After the retention time is complete, exhaust valve 163 is opened and the pressurized fluid inside the hollow is exhausted to the atmosphere. The pressure of the pressurized fluid is rarely fluctuated during blow molding, but in cases where a profile of the pressure of the pressurized fluid to be injected is to be drawn, for example by initially injecting at high pressure, then lowering the pressure of the pressurized fluid to be injected and then raising it again, the pressure of the pressurized fluid to be injected is measured, and this pressure is fed back to the molding machine's PLC, and the injection pressure is controlled using reference number 165, a needle-type regulator (pressure adjustment valve) that is capable of automatic pressure adjustment.

[0105] When the molding machine retracts the ejector plate (B) consisting of the numbers 117 and 118 at the start of the atmospheric release (the timer starts counting) or after a certain time has elapsed from the start of the counting (this time can also be set to any time), the number 120 also retracts, so the pressurized fluid in the hollow part is completely exhausted and no residual pressure remains, and the problem of bulging and bursting is solved even when the mold is opened. Furthermore, number 120 must be at the forward end before the next resin is filled.

[0106] (Pressurized fluid injection, retention, and evacuation during blow molding) (For external controllers) When using an external controller to operate the equipment in Figure 35, a separate controller is provided to control this equipment, and signals are output and input from the molding machine, interfaced with the controller to operate the equipment in Figure 35 and perform blow molding. The timing of pressurized fluid injection is during the resin filling and after the filling is completed. In the case of during the filling, when the screw passes a predetermined position, the molding machine outputs a signal to the controller to command the pressurized fluid injection. The controller receives this signal and opens the injection valve 161 to start injecting the pressurized fluid into the molten resin. The time for injecting the pressurized fluid is set by a timer installed in the controller, and when the time is up, the valve 161 is closed to confine the pressurized fluid inside the hollow. The inventors call this the "retention time". The length of the retention time is set by a timer installed in the PLC in the controller, which can be set at will. After the retention timer is up, the valve 163 is opened and the pressurized fluid inside the hollow is exhausted to the atmosphere. The exhaust time (called the "release time", "exhaust time", etc.) is set by a timer installed in the PLC, making it possible to set the time at will. When the atmospheric release begins (the timer starts counting), or after a certain amount of time has passed since the start of the count (this time can also be set arbitrarily), or when the atmospheric release timer finishes counting, an ejector plate retraction signal is sent to the molding machine, and when the molding machine receives this signal and retracts the ejector plate (B) consisting of numbers 117 and 118, number 120 also retracts, so the pressurized fluid in the hollow part is completely exhausted and no residual pressure remains, and the problem of bulging and bursting is solved even when the mold is opened. Furthermore, number 120 must be at the forward end before the next resin is filled.

[0107] (Compressed Air Molding) (When writing to the molding machine's PLC) In blow molding, pressurized fluid is injected into the resin filled in the cavity. In compressed air molding, the pressure (force) of the pressurized fluid is inserted into the gap between the molten resin filled in the cavity and the mold, improving the transferability to the opposite surface. The equipment used is that shown in Figure 35, and the mold is that shown in Figure 26. The timing for jetting the pressurized fluid is either during filling, after filling is complete, or a short time after filling is complete, just like with blow molding {If multiple pieces of equipment in Figure 35 are used, prepare a program for each piece and set the best pressurization time (timing) for each.} The settings for the subsequent holding time and exhaust time are almost the same as with blow molding.

[0108] In compressed air molding, the cooling and solidification speed slows down when the mold temperature is increased, so the transfer effect of the pressurized fluid is increased. In this case, in order to prevent the pressurized fluid from entering the molten resin (inside) instead of entering the gap between the resin and the mold, resulting in a hollow molding, the ejector plate (C) consisting of the ejector plate (129) and the ejector plate (130) is moved back during the resin filling process and before the pressurized fluid is ejected after the filling process is completed, creating a small space where the pressurized fluid is ejected, and the pressurized fluid is ejected into that space. The ejector plate (C) consisting of the ejector plate (129) and the ejector plate (C) is moved back during the resin filling process and before the pressurized fluid is ejected after the filling process is completed, the pressurized fluid is ejected into that space. The ejection of the ejector plate (C) consists of the ejector plate (129) and the ejector plate (C) consists of the ejector plate (130) is moved back when the cavity is filled with molten resin and a certain amount of time has passed from 0 seconds (the time can be set arbitrarily). This operation is performed by a program written in the PLC in the molding machine.

[0109] (Compressed Air Molding) (For external controllers) When an external controller is used for compressed air molding without writing a program in the PLC of the molding machine, the process is almost the same as that of the blow molding. The retraction of the reference number 126 is performed by sending a retraction signal from the molding machine to the controller, and the timer in the controller retracts the machine after a certain time has elapsed from 0 seconds after starting. After the timer has timed out, the reference number 161 is opened and compressed air molding is started. After the compressed air time has elapsed, the valve 161 closes, trapping and holding the pressurized fluid, and when the holding timer has finished, the exhaust timer starts counting and the exhaust valve of the reference number 163 is opened to release the pressurized fluid into the atmosphere. When the release of the pressurized fluid is completed (time-out for atmospheric release is completed), the controller sends a mold-opening permission signal to the molding machine, and the molding machine receives this signal, and when various conditions such as the completion of the cooling time are met, the mold is opened and the molded product is removed. The molding machine sends a mold-opening signal to the controller and resets the controller program. Note that the reference number 126 must be at the forward end before the next resin is filled.

[0110] (manual) Since a series of operations such as injecting liquid, stopping, opening valve 151, opening valve 154, opening valve 161, and opening valve 163 must be performed manually, a manual switch is provided on the PLC of the molding machine, and, if an external controller is used, on the external controller. When an external controller is installed, signals must be exchanged between the molding machine's PLC and the external controller's PLC, which makes the programs for both complicated. It is simpler and more economical to write programs for gas and liquid injection, GCP, blow molding, compressed air molding, etc. in the molding machine's PLC. Furthermore, when implementing these programs as combined operations, signal exchange becomes complicated, so it is recommended to use the molding machine's PLC rather than an external controller.

[0111] The following will be described using comparative examples, examples, and embodiments. Comparative Example 1

[0112] A pellet of linear aromatic PC resin {Teijin Chemical Co., Ltd., Panlite-L1225WP}, color natural color (transparent), which had been dehumidified and dried at 80℃ for 2 hours, was mixed with 0.7wt.% of sodium bicarbonate {(sodium bicarbonate, sodium bicarbonate, NaHCO3) raw powder, so it is white powder}, which is an inorganic chemical foaming agent, and foam molding was performed without GCP using a 180-ton injection molding machine manufactured by Toyo Machinery and Metal Co., Ltd., in a mold with the product shape (top plate thickness 2mm) shown in Figures 1 and 2. The surface temperature of the mold during molding was about 45℃ on both the fixed (cavity) side and the movable (core) side, and the molten resin temperature was 260℃. The screw of the injection molding machine was cut off at the forward end without using a holding pressure, and there was a slight tendency for short molding {there was no chipping of the shape (short mold, short shot) etc.} and subjected to injection molding to obtain a foamed molded product using sodium bicarbonate as a foaming agent. The surface of the foam-molded product obtained had swirl marks because GCP had not been implemented. In order to check its strength, the molded product was placed on the floor and a person weighing 75 kg slowly put his entire weight on it from above. As a result, it was confirmed that the strength of the original PC was completely lost and that it was as brittle as shrimp rice crackers, and foam-molded PC products using sodium bicarbonate as a foaming agent cannot withstand normal use. Sodium bicarbonate as a foaming agent is not suitable for foam-molding PC. Comparative Example 2

[0113] In Comparative Example 2, the sodium bicarbonate foaming agent used in Comparative Example 1 was changed to ADCA (yellow powder in nature) an organic chemical foaming agent. The amount added was 0.35 wt.%, half the 0.7 wt.% of sodium bicarbonate. The mold, injection molding machine, and molding conditions used were otherwise the same. The obtained molded product was loaded and checked for strength in the same way as in Comparative Example 1, but like Comparative Example 1, it had no strength, and PC molded products using ADCA as a foaming agent cannot withstand use like normal PC molded products. ADCA as a foaming agent is not suitable for PC foam molding. Comparative Example 3

[0114] Using the liquid injection device shown in FIG. 1 of PCT / JP2015 / 062611 and the injection port provided in the heating barrel (shown in FIG. 4 and FIG. 5 of PCT / JP2015 / 062611), a certain amount of ethanol (chemical formula is C2H5OH) was continuously injected at the beginning of the compression zone of the screw in the heating barrel with respect to the weight of the molded product (a value measured at one time) from the start of metering to the end of metering, and foamability was imparted to the plasticized molten resin using ethanol (the ethanol vapor was vaporized in the heating barrel and pressure-dissolved and / or finely dispersed in the molten resin melt-kneaded during metering). A foam-molded product was obtained in the same manner as in Comparative Example 1 and Comparative Example 2. A load was applied to check the strength in the same manner as in Comparative Example 1 and Comparative Example 2, but there was no strength as in Comparative Example 1 and Comparative Example 2, and the PC foam-molded product using ethanol as the foaming agent was not usable. Ethanol as a foaming agent is not suitable for PC foam molding. The same can be done using isopropanol (C3H7OH) instead of ethanol, but alcohol is not suitable for use in the production of PC foam molded products.

[0115] Unlike the PC, the ABS foam molded products, m-PPO (PS or HIPS modified, PA modified, PP modified), PP foam molded products, and 6-nylon foam molded products using the ethanol (EtOH) and isopropanol (IPA) mentioned above show almost no deterioration in physical properties. It is presumed that the molecular structure of the PC changes (becomes lower molecular weight) as a result of the attack by the vapor of ethanol and IPA that reaches a supercritical state inside the heating cylinder, causing a deterioration in physical properties. For the same reason, the foam molded products using PET and PBT with ethanol and IPA also show a significant deterioration in physical properties. Comparative Example 4

[0116] In the above Comparative Examples 1, 2, and 3, no GCP was applied, and swirl marks were generated on the surface of each foam-molded product. GCP was applied using the nozzles shown in Figs. 20 to 22 of PCT / JP2015 / 062611, the seal mold sealed for GCP shown in Figs. 23 and 25, and the GCP device shown in Fig. 24 (the gas used was 1.4 MPa air compressed by a reciprocating type compressor. In the present invention, the seal mold shown in Figs. 20 and 21 and the GCP device shown in Fig. 15 were used). Foam molding was performed to obtain a foam-molded product with a clean skin layer without swirl marks on the surface and fine foam cells (foam layer) inside. However, the strength was confirmed in the same way as in Comparative Examples 1, 2, and 3, and the strength was significantly reduced as in Comparative Examples 1, 2, and 3. EXAMPLES

[0117] While searching for a foaming agent for PC resin from the above Comparative Examples 1 to 4, undried PC (linear aromatic PC resin {Teijin Chemicals Co., Ltd., Panlite-L1225WP}) resin pellets (water absorption rate is about 0.1 wt.%) were molded without using the foaming agent sodium bicarbonate in Comparative Example 1. As a result, several voids caused by the moisture in the resin (moisture that had originally been absorbed) were generated in the spool, runner, and molded product. However, the molded product using this undried PC did not experience a decrease in strength. From this, the inventor hypothesized that water could be used for foam molding of PC, and found the possibility and effectiveness of water from the results of preliminary experiments. After intensive research, the inventor confirmed the fact that water is effective for foam molding of PC resins, and broadly ester resins, and completed the present invention.

[0118] In Comparative Example 3, foam molding was performed using 0.5 wt. % water (distilled water, ion-exchanged water, tap water, city water) instead of ethanol. As a result, as shown in Figure 3, the foam cells are large at several mm (millimeters). However, when water is used as the foaming agent, there is no deterioration in physical properties as with ethanol, and no cracks occur even when loaded. The physical properties of the PC foam-molded product are fully maintained, and water is an effective foaming agent for obtaining a foam-molded product that is fully usable as a PC molded product. EXAMPLES

[0119] (foaming nucleating agent) 100 parts by weight of linear aromatic PC resin (Teijin Chemical Co., Ltd., Panlite-L1225WP) was mixed uniformly with 5 parts by weight of aluminum oxide using a tumbler, and the mixture was fed into a vented twin-screw extruder to produce a pellet-shaped resin composition, which was designated as A001, a master batch containing 5 parts by weight of aluminum oxide as a foam nucleating agent.

[0120] Similarly, a foam nucleating agent master batch B001 was prepared containing 5 parts by weight of silver oxide instead of aluminum oxide.

[0121] Similarly, a foam nucleating agent master batch C001 was prepared containing 5 parts by weight of silicon dioxide instead of aluminum oxide.

[0122] Similarly, a foam nucleating agent master batch D001 was prepared containing 5 parts by weight of silicon carbide instead of aluminum oxide. EXAMPLES

[0123] In Example 1, since no foam nucleating agent was used, the foam cells were large and coarse, but in Example 2, the action and effect of each of the foam nucleating agents aluminum oxide, silver oxide, silicon dioxide, and silicon carbide was confirmed to determine whether the foam cells could be made finer. Panlite-L1225WP was mixed with 5 parts of foam nucleating agents, Masterbatch A001, Masterbatch B001, Masterbatch C001, and Masterbatch D001, separately, per 100 parts of PC resin pellets (mixing ratio = 100:5), and water (distilled water was used) was injected into the heating cylinder at a volume of 0.4% of the volume of resin in the same manner (conditions) as in Comparative Example 1 to obtain a PC foam-molded product using water as a foaming agent. The injection foam-molded product obtained in this Example 3 had a foam structure with fine foam cells due to the action and effect of the foam nucleating agents A001, B001, C001, and D001. From the results of Example 3, the substances that make the foam cells fine in foam molding, contained in the foam nucleating agents Masterbatch A001, Masterbatch B001, Masterbatch C001, and Masterbatch D001, contained in PC, sufficiently made the foam cells fine. The obtained foam-molded products containing the foam nucleating agents aluminum oxide, silver oxide, silicon dioxide, and silicon carbide were loaded and their strength was checked in the same manner as in Comparative Example 1. As a result, there was almost no deterioration in the physical properties of the PC due to the inclusion of the foam nucleating agents aluminum oxide, silver oxide, silicon dioxide, and silicon carbide. Of course, there was almost no deterioration in the physical properties due to the foaming agent water. EXAMPLES

[0124] When the GCP described in Comparative Example 4 was applied to Example 3, a foam-molded product was obtained that had a clean skin layer without swirl marks on the surface and foam cells of about 50 μm or less inside. EXAMPLES

[0125] In the above-mentioned Examples 3 and 4, the foam nucleating agents Masterbatch A001, Masterbatch B001, Masterbatch C001, and Masterbatch D001 were used separately and alone, but the amount of foam nucleating agent was mixed and used by mixing two or more kinds of master batches, such as 5, A001 2.5 and B001 2.5, or A001 2.5 and C001 2.5, as in the examples. In the case of three types of foam nucleating agents, A001, B001, and C001, the mixing ratio was 5, or when all of A001, B001, C001, and D001 were used, the action and effect of each foam nucleating agent was fully exerted, and it was confirmed that the foam cells were finer. Naturally, the more the amount of foam nucleating agent added, the finer the foam cells, and the less the amount added, the coarser the foam cells. Because it is a master batch, the desired foam cell size can be achieved by controlling the amount added, whether it is large or small. When implementing GCP, the optimum amount can be found by checking whether or not swirl marks occur on the surface (adding more foam nucleating agent makes the foam cells finer, but the foaming power increases and swirl marks occur on the surface. In this case, by increasing the GCP pressure or using carbon dioxide gas in the GCP, it is possible to produce a foam molded product with a clean surface without swirl marks). EXAMPLES

[0126] Can the present foam nucleating agents, aluminum oxide, silver oxide, silicon dioxide, and silicon carbide, refine the foam cells not only with PC alone but also with PC-based resins? As a result of confirming the usefulness of using water as a foaming agent, the methods of Examples 2 to 4 were carried out for all of the molding materials shown below, and the results showed that it was effective. The resins used were PC / ABS, PC / PS (polystyrene), PC / PVC (vinyl chloride, polyvinyl chloride), PC / polyamide (PA), etc. When using water as a foaming agent with PC-based resins, distilled water is preferable, but ion-exchanged water is also acceptable. City water or well water can be used, but calcium ions (Ca 2+ ), magnesium ion (Mg 2+The presence of ), accelerates the decomposition of PC, so it is preferable for the total hardness (total concentration of calcium ions and magnesium ions) to be 100 ppm or less (water), and even better to have it at 35 ppm. Although foam nucleating agents also have an effect on PC / PET, PC / PBT, and PC / PEN (polyethylene naphthalate), as mentioned above, these resins hydrolyze in the case of PET, PBT, and PEN, resulting in a significant decrease in physical properties. These foam nucleating agents are not limited to PC resins, but can also be used as foam nucleating agents for styrene resins such as ABS and HIPS, olefin resins such as PP, nylon resins, and vinyl resins such as PVC. EXAMPLES

[0127] During the plasticization and weighing of Sumika Polycarbonate Co., Ltd.'s PC {SD Polyca (product name) 301-15 (grade)}, 0.5 wt.% of ion-exchanged water was injected from the start of weighing to the end of weighing, based on the weight of the molded product (weight of the molten resin in the heating cylinder) shown in Figures 1 and 2, and vaporized in the heating cylinder, imparting foamability to the heated and melted PC resin, resulting in the molded product shown in Figure 3. Since no foam nucleating agent was mixed into the molded product obtained, the foam cells were coarse and large, about 2 mm to 5 mm, but there was no deterioration in physical properties as with baking soda, ADCA, or ethanol, and the original physical properties of PC were displayed (Figure 3).

[0128] Immediately after the GCP was evacuated, the movable mold was moved back 1 mm, and the mold back was performed 1 mm from the plate thickness of 2 mm immediately after the GCP was evacuated, increasing the foaming ratio. The pressure applied to the resin molded product was reduced by the mold back, and as a result, the foam cells grew to 10 mm, and in some places reached 20 mm (Fig. 4). Despite the molded product having such large foam cells, the inside of the mold was pressurized to 1 MPa using the GCP device shown in Fig. 15, and water was used under pressure to impart foaming properties to the above-mentioned PC resin molded product. The surface was completely free of swirl marks, and was smooth and clean (Fig. 4). Furthermore, the surface of the molded product, such as that shown in Figure 4, is textured to prevent the raindrop phenomenon, a defect specific to GCP.

[0129] GCP was performed with air at a pressure of 1 MPa, and a foamed molded product with a beautiful surface was obtained, but because no foam nucleating agent was added, the foam cells were very large (size (diameter) was about 5 mm, and in some places was more than 5 mm) (Figures 3 and 4). EXAMPLES

[0130] When Sumika Polycarbonate Co., Ltd.'s PC {SD Polyca (product name) SI8000L (grade)} was foamed with ion-exchanged water in the same way, ultra-fine foam cells were obtained. When GCP was performed with the same air at a pressure of 1 MPa, the foaming power was too strong and it was not possible to push the swirl marks on the surface. In the above Example 7, only 301-15 was used, so the foam cells were coarse and large, but by using (mixing) SI8000L, the foam cells were refined, and it was confirmed that the swirl marks on the surface could be somewhat suppressed by GCP. 70 parts of 301-15 pellets were mixed with 30 parts of SI8000L pellets, and the components in SI8000L were used as a foam nucleating agent. Compared to Figures 3 and 4, the foam cells were refined, and it was visually confirmed that foam cells of 1 mm or less were uniformly distributed inside the molded product (Figure 5). The foam nucleating agent used in this example was a light diffusing agent. EXAMPLES

[0131] A mixed resin of 80 parts of 301-15 pellets and 20 parts of SI8000L pellets was foamed using ion-exchanged water in the same manner. GCP was carried out in the same manner as in Examples 7 and 8, and although the number of swirl marks on the surface was further reduced compared to Example 8, a clean foamed product without swirl marks could not be obtained. EXAMPLES

[0132] Example 10 is a case where the mixing ratio of Example 9 is changed, and the mixing ratio is 90 parts of 301-15 and 10 parts of SI8000L. As a result, the swirl marks on the surface disappeared with GCP using 1 MPa air (the gas used was compressed by a compressor at a pressure of about 1 to 1.2 MPa), and a PC foam-molded product with a smooth and clean surface and fine and clean foam cells was obtained. It was confirmed that the strength of the foam-molded product obtained was sufficient. Figure 5 (photo) shows that in this Example 8, the core side was retreated by 0.5 mm after exhausting the GCP, and the foaming ratio {(2 mm + 0.5 mm (mold retreat amount = mold opening distance) ÷ 2 mm (initial plate thickness) = 1.25 (volume expansion of 25 vol.%) was increased. The diameter of the foam cells was about 1 mm and was present throughout the molded product. Due to the action and effect of the GCP, the surface of the molded product was completely free of swirl marks and was smooth and clean. EXAMPLES

[0133] A polymer alloy of PC and ABS manufactured by Sumika Polycarbonate Co., Ltd. {SD Polyca (product name) IM6011 (grade)} was foam-molded using ion-exchanged water in the same manner as in Example 7. The GCP was air and the pressure was 1 MPa. The PC / ABS ("PC / ABS" means a polymer alloy of PC and ABS) used in this Example 11 was black in color, and the pigment acted as a foam nucleating agent, resulting in a fine foam layer inside and a smooth, beautiful foam-molded product with no swirl marks on the surface. When ethanol was used as a comparative example, the physical properties were decreased. From this, it is concluded that water is also an effective blowing agent for PC-based polymer alloys. EXAMPLES

[0134] In this Example 12, the resin used in Example 11 was confirmed to be that of another company. Instead of IM6011, PC / ABS {Techniace (product name) T-251T-15 (grade)} from Nippon A&L Co., Ltd. was used. The obtained foam molded product had a smooth surface and fine foam cells inside, similar to Example 11. When ethanol was used as a comparative example, the physical properties were reduced. From this, it is judged that water is also effective as a foaming agent for PC-based polymer alloys. EXAMPLES

[0135] A polymer alloy of PC and PET (polyethylene terephthalate) {SD Polyca (product name) IM401-18 (grade)} manufactured by Sumika Polycarbonate Co., Ltd. was used and foamed with ion-exchanged water in the same manner as in Example 7, but the physical properties of PC / PET were not observed at all, and it was assumed that this was due to hydrolysis of PET. PET is used for cosmetic containers. When this cosmetic PET resin is foamed with alcohol, no deterioration in physical properties is observed. EXAMPLES

[0136] The inclined pins shown in Figures 23 and 24 were sealed with a load type O-ring, and the load type O-ring 106 was fixed with a nest 113 in a sealing mold. After confirming that there were no leaks, air was used as the gas and a pressure of 1.4 MPa was applied in the GCP device shown in Figure 15, and this sealing mold was used for foam molding using PP as the molding resin and a liquid mixture of ethanol and tap water in a 4:6 ratio as the foaming agent, and a foam molded product with a smooth and beautiful surface without swirl marks was obtained. EXAMPLES

[0137] The inclined pin shown in Figures 23 and 24 was sealed with a load type O-ring, and the load type O-ring 106 was fixed with a die insert 113, and the seal mold was subjected to pressure molding at a pressure of 30 MPa using the blow molding and pressure molding device shown in Figure 35. There was no leakage of pressurized fluid from the shaft (reference number 108) of the inclined core, and it was confirmed that the action and effect of fluid pressurization was sufficient. The molding materials used were PP and ABS. EXAMPLES

[0138] In the mold shown in Figure 25, the resin was PP, and the foaming agent was a mixed solution of water and ethanol 4:6 shown in Example 14. The GCP (to be precise, outer GCP) of Example 14 was performed, and the foaming molded product had a smooth and beautiful surface with no swirl marks on the surface. Inner GCP (hollow molding using foamable resin) was performed from the inside at a pressure of 30 MPa. When the internal pressure was sufficient, the pin 120 was retracted, the pressure inside the hollow part was suddenly reduced, and foaming was performed toward the inside. After cooling and solidification were completed, the mold was opened, but no swelling or bursting was observed. The effectiveness of retracting the pin 120 was confirmed even in the inner GCP using foamable resin according to this Example 16. EXAMPLES

[0139] Using the mold shown in Fig. 36, blow molding was performed with the HIPS injection device shown in Fig. 35. In order to eliminate the residual pressure in the hollow, the pin 120 was retracted, the pressure inside the hollow was suddenly reduced, and the mold was then opened, but no swelling or bursting due to the residual pressure in the hollow was observed. This Example 17 confirmed the effectiveness of retracting the pin 120 even in blow molding using a non-foaming resin. EXAMPLES

[0140] The inclined cores (reference numbers 10.7, 108, etc.) shown in Fig. 23 were inserted into the mold shown in Fig. 20, with the load-type O-ring 106 held down by a nest as shown by reference number 113 in Fig. 23. Using this mold, the above-mentioned Examples 1 to 15 were carried out, and it was confirmed that the sealing of the inclined cores was also possible as shown in Fig. 23. Furthermore, using the mold of Example 18, pressure molding was carried out at a nitrogen gas pressure of 30 MPa, and it was confirmed that the mold using the nesting structure to seal the inclined cores was sufficiently pressure-resistant to pressure molding, and had sufficient sealing properties. EXAMPLES

[0141] Example 18 is a mold in which the inclined pins in FIG. 23 are sealed, whereas Example 19 is a sealed mold in which multiple inclined cores and ejector pins are sealed with a load-type O-ring 106 and fixed with a nest 113 as shown in FIG. 24. It has been confirmed that this sealed mold is fully capable of mass production by foam molding using the GCP in Example 18 and compressed air molding. EXAMPLES

[0142] Figure 7 shows an IC tray mold with six pin gates of about φ4 mm on the product surface (reference number 4 is the IC tray cavity). In this case, instead of opening the PL first, reference number 8 was opened and the pin gates were cut, then the PL was opened and molded back to increase the expansion ratio. ABS and modified PPO (PP modified with PPO) were used as resins for foam molding, and a foam molded product was obtained with a weight reduction of about 30% (about 10% for the amount not using dwell pressure, as this is foam molding, and about 20% for the mold expansion due to mold back). A GCP of 1.2 MPa was used with air, and it was confirmed that a foam molded product with a clean surface and no swirl marks could be obtained. Since IC trays require high dimensional accuracy and little warpage, foam molding and blow molding, which do not use dwell pressure and are molded at low dwell pressure, are good. Foam molding uses a foaming agent, which can be gas, liquid, or solid. Considering the risk of foaming residue in the foam-molded IC tray affecting the IC, gases such as nitrogen gas and carbon dioxide gas, which do not leave foaming residue, or alcohols such as ethanol and IPA, and water are good. Foam molding and blow molding also require less than half the clamping force compared to conventional solid molding, so in addition to stack molding, multiple molded products with the shape of the molded product processed on the same PL surface, and multiple molded products of different types can also be implemented. In fact, the IC tray in Figure 7 (Figure 10 is the IC tray processed in Figure 7) is 135 mm long, 315 mm wide, and 8 mm thick, and in normal molding it is processed in one mold using an injection molding machine with a clamping force of 180 tons. However, in foam molding, the clamping force required is at most 80 tons, so a two-cavity process was used in which two of the same IC trays were processed in one mold, or a two-cavity process was used in which two IC trays of different shapes were processed, and an IC tray with satisfactory quality and little warping or deformation was obtained. EXAMPLES

[0143] A gas injection pin was attached to the fixed side of the runner in Figure 7, and the nitrogen gas was increased to 20 MPa. After filling the cavity with non-foaming resin, gas was immediately injected for 5 seconds to form a hollow section. The gas was then trapped (retained) in the hollow section for 10 seconds, vented, and a hollow molded product with a hollow ratio of 8% (compared to the weight of general molding) was obtained. EXAMPLES

[0144] In the above-mentioned Example 22, a hollow was formed after filling the cavity with a non-foamable resin, but in this Example 22, the mold was retreated by 0.2 mm (mold back) while injecting high pressure gas, resulting in a hollow ratio of nearly 20%. Note that the same experiment was carried out with a foamable resin that had been given foamability using ethanol in Examples 21 and 22, verifying that hollow molding is possible even when a foamable resin is used. EXAMPLES

[0145] Mats that are attached to the floor of an automobile are made of rubber and thermoplastic elastomer (TPE), and in this Example 22, foam molding was performed using elastomer. The foaming agents used were Advancel (trade name) and Expancel (trade name) with medium air bubbles, a master batch with 20 wt.% ADCA supported on the surface of an olefin-based elastomer (TPV), a master batch with 20 wt.% sodium bicarbonate supported on the surface of an olefin-based elastomer (TPV), and ethanol as a liquid foaming agent. It was confirmed that it was possible to foam an olefin-based elastomer using any of the foaming agents. Similarly, foaming was possible with TPS and TPU. It was confirmed that the physical properties of ester-based TPC decreased with both solid and liquid foaming agents, and only nitrogen gas was used for foaming of TPC. TPE is broadly divided into seven categories, including the above-mentioned TPV, TPA, TPC, TPO, TPS, TPU, TPV, and TPZ, and is further divided into 32 categories based on the difference between the hard segment and the soft segment. This Example 22 was explained using an automobile mat as an example, but it is presumed that foam molding is possible for all molded products using TPE. Of course, foam molding alone will cause swirl marks on the surface, so we performed GCP with TPV and TPS using air at a pressure of 1MPa, and obtained a foam structure with no swirl marks on the outside and fine foam cells inside. If the GCP air gets caught and raindrops occur due to the GCP, open the mold by about 0.1mm to 0.2mm after exhausting the GCP to smoothly exhaust the compressed air in the gap between the resin and the mold. Furthermore, if the inside of the mold is vacuumed after exhausting, raindrops can be reduced even further.

[0146] Using an 850-ton injection molding machine manufactured by Toyo Machinery & Metals Co., Ltd., foam molding was performed using an olefin-based thermoplastic elastomer (hereinafter referred to as material "A"). The foaming agents used were sodium bicarbonate and ADCA. First, the results of foam molding using sodium bicarbonate are explained. A foaming agent master batch was produced by supporting 20 wt.% of sodium bicarbonate on the pellet surface of material A. Material A was blended so that the content of sodium bicarbonate alone in material A was 0.5 wt.%, and foam molding was performed at the melting temperature of material A, 215°C. The obtained foam molding product had no swirl marks on the surface and a foam layer was confirmed inside, but the foaming power of sodium bicarbonate was insufficient and sink marks occurred. ADCA was used instead of sodium bicarbonate, and the ADCA content was 0.25 wt.%, half that of sodium bicarbonate, and a foam molding product with a beautiful surface without swirl marks was obtained without using GCP, just like the case of sodium bicarbonate. The foam cells inside were a mixture of fine ones and coarse (large) ones. We judged that the large foam cells were due to a lack of foaming agent, and increased the ADCA to 0.5wt.%, resulting in fewer coarse foam cells, but no swirl marks on the surface. The initial thickness of the molded product was 3mm, and after filling was completed, the mold was molded back 0.2mm to increase the foaming ratio. Next, a hole was made in the place where liquid can be injected into the heating barrel of the molding machine {close to the compression zone of the screw; in foam molding using liquid, if alcohol or other substances are put into the heating barrel, it will vaporize all at once. It is better to have the molten resin wrapped around the screw and seal it so that the vaporized steam does not leak into the hopper. A liquid injection port was provided in front of the place where the molten resin is wrapped around the screw (towards the nozzle).}, and ethanol was poured in from there, and the vaporized and plasticized weighed material A was given foaming properties, and foam molding was performed. As a result, unlike the cases of baking soda and ADCA, swirl marks occurred on the surface. The difference in the occurrence of swirl marks is that in the case of chemical foaming agents, when the foaming agent master batch is mixed with material A and fed into the heating cylinder from the hopper, some of the foaming agent immediately decomposes thermally and generates foaming gas. Most of the foaming gas generated in thermoplastic resins such as PP and ABS is finely dispersed and dissolved in the resin, and only a small amount escapes to the hopper side, so the foaming resin filled in the cavity has sufficient foaming power, and many swirl marks occur on the surface.On the other hand, with material A, the resin plasticized and melted at a slow rate, and in the case of the chemical foaming agents sodium bicarbonate and ADCA, the decomposition rate of the chemical foaming agent was faster than the plasticization rate of material A, and most of the foaming gas escaped into the hopper, failing to impart the desired foaming power to material A, so there was not much foaming, and the occurrence of swirl marks was hardly observed. On the other hand, with alcohol, the foaming agent ethanol was added to the resin near the compression zone (to the molten resin) after melting was completed, so many swirl marks occurred. The above material A was mixed with 5 wt.% calcium carbonate as a foam nucleating agent.

[0147] Since the foaming agent used in material A is supported on the surface of the pellets of material A, it is better to use a foaming agent that has been melted and kneaded to contain the foaming agent inside. It is better to plug the heating cylinder after feeding the material containing the foaming agent master batch from the hopper into the heating cylinder so that the foaming gas does not escape to the hopper side. Example 23 was explained using an automobile mat, but the embodiment can be applied to all foam-molded products molded with TPE, not just mats. EXAMPLES

[0148] In Example 23, a master batch of a foaming agent in which ADCA or sodium bicarbonate was supported on the surface of material A to be foamed was used. In this Example 24, a master batch was not used, and pellets of material A containing 0.25 wt. of ADCA were produced in advance in the granulation (pelletization) process (stage) of material A. The ADCA-containing pellets were used in the injection molding machine and mold used in Example 23. As a result, a foam-molded product of material A with an even higher expansion ratio than that of Example 23 was obtained.

[0149] A similar experiment was carried out using 0.5 wt. % sodium bicarbonate instead of ADCA, and it was confirmed that the expansion ratio was also higher than in Example 23. The reason why the expansion ratio is higher than that of the method of Example 23 is that when the TPE of material A is melted, for example, ABS, PP, etc., the viscosity drops quickly when melted, and the foaming gases such as nitrogen gas, carbon dioxide gas, and water vapor can be included in the resin (finely dispersed in the molten resin, dissolved under pressure, etc.), but in the case of material A, the viscosity does not drop so quickly even when melted, so most of the foaming gas generated by the thermal decomposition of the foaming agents such as ADCA and baking soda escapes from the hopper. In Example 24, the necessary amount of foaming agents such as ADCA and baking soda are kneaded into material A, so that when material A melts, heat is applied to the foaming agent for the first time and it starts to decompose thermally, making it easier to include a lot of foaming gas in material A, and as a result, sufficient foaming can be achieved even with a small amount of foaming agent. In this Example 24, ADCA and baking soda are shown, but it is also possible to carry out the method with DPT, other hydrogen carbonates (Li, Na, K, Rb, Ca, Mg, etc.) and air spheres. Of course, in this case, if a GCP is used, swirl marks can be suppressed. Naturally, in order to further improve the kneading ability, it is possible to use dulmage or to design the flights so that they have high kneading ability.

[0150] (Embodiment 1) From Comparative Examples 1 to 4 and Examples 1 to 5, it can be seen that if a PC resin is used, water is used as a foaming agent, and aluminum oxide, silver oxide, silicon dioxide, or silicon carbide is used as a foaming nucleating agent, it can be carried out not only with an injection molding machine but also with extrusion molding, and if the foamable resin that has come out (extruded) from the die is passed through a gas (which can be air, nitrogen gas, or carbon dioxide gas) with a pressure of 0.6 MPa or more, and the principles and means of GCP are also applied to extrusion molding, it is possible to suppress foaming on the surface and achieve extrusion molding without swirl marks.

[0151] (Embodiment 2) In Examples 1 to 5 and in Embodiment 1, it has been described that water is used as the foaming agent, but even in the case of Musel, Amotech, and Sofit (product name?), which are foam molding products using gases such as nitrogen gas and carbon dioxide gas, the foam nucleating agents such as aluminum oxide, silver oxide, silicon dioxide, and silicon carbide exemplified in this invention use PC-based resins, and the action and effect of the foam nucleating agent is fully exerted when implemented in injection molding, extrusion molding, and blow molding.

[0152] (Embodiment 3) The present invention adds to and asserts that the present invention encompasses all of the parts involved in foam molding (GCP devices, sealing molds, molding machines, and ancillary equipment such as shut-off nozzles) contained in PCT / JP2015 / 062611, PCT / JP2015 / 069216, PCT / JP2016 / 086380, and PCT / JP2020 / 015536.

[0153] (Embodiment 4) In the foam molding of PC resins, the foaming agent used in the examples of this invention is water, and there are many other foam nucleating agents that can be used other than aluminum oxide, silver oxide, silicon dioxide, and silicon carbide, as long as they do not decompose PC. Mix wet PC (water-absorbed PC) with another foam nucleating agent (spread it on the PC surface with a small amount of water), and use an injection molding machine to mold test pieces to check for any significant decrease in physical properties (decomposition of PC). If there is no significant decrease in physical properties, it can be judged to be a usable foam nucleating agent.

[0154] (Embodiment 5) (Methods for increasing foaming ratio) In foam molding, the means for increasing the expansion ratio include increasing the amount of foaming agent added to increase the foaming power of the resin, filling the cavity with foamable resin and expanding a part of the mold to reduce the pressure of the filled foamable resin to make foaming easier, lowering the screw to reduce the pressure of the foamable resin to make foaming easier, and opening the mold to increase the expansion ratio. When opening the mold, the mold structure can be either flat parting (mold structure shown in Figures 11 and 12, movable side mold retraction movement) or vertical parting (mold structure shown in Figures 13 and 14, movable side mold retraction movement). The former is called mold back and the latter is called core back, and they are distinguished in this invention. When the mold back is opened widely, there is a risk of flash occurring on the PL, so it is not opened very widely. In the case of core back, there is less risk of flash occurring on the PL, so a molded product with a large expansion ratio can be obtained.

[0155] (Molding equipment) This embodiment 5 can be implemented in either mold back or core back. There are two-plate and three-plate injection molds (mold structure). When mold back or core back is performed with a two-plate mold, the movable die plate of the injection molding machine is moved back a predetermined amount (distance) to expand the cavity (mold, cavity) and increase the foaming ratio. In general injection molding, when a three-plate mold is opened, if the PL opens first, it may be difficult to open the stripper plate (the sweeper plate for the spool runner), so it is common to provide a PL lock mechanism for the PL and open the fixed mold plate and stripper plate first. However, even if the movable die plate of the injection molding machine is moved back with this mold structure, the stripper plate opens due to the PL lock, and mold back or core back is not achieved. As a means of solving this problem, the inventor does not use a PL lock, but instead fits a spring or urethane rubber into the PL, and by moving the movable die plate back a predetermined distance, the spring or urethane rubber will always open the PL first, allowing mold back and core back. A gas spring can be used instead of the spring or urethane rubber. A hydraulic cylinder or pneumatic cylinder can also be used. The inventor called this a "first mold opening mechanism, first mold opening mechanism." After the mold back and core back are performed to increase the foaming ratio, and cooling and solidification are completed inside the mold, the die plate is lowered (retracted) to remove the foam molded product, but since there is no PL lock, the stripper plate does not move and the spool runner does not leave the mold. At this point, the inventor pulls the movable mold and the stripper plate using a pull ring, pull bolt (rod), chain, or chain to move the stripper plate by using the mold opening, and remove the spool runner from the mold (mold release). Measures are taken to ensure that tension rings, chains, and other fasteners do not break or snap when the mold is opened (for example, a spring is installed in the tension bolt). In addition to directly connecting the movable die and the stripper plate with a tension ring or the like, the movable die and the fixed die may be connected with a tension ring or the like, and the fixed die and the stripper plate may be connected with a tension ring or the like. Figures 6 and 7 show a three-plate type that uses the above-mentioned tension ring, but in the case of a two-plate type, a spring, urethane, etc. can also be installed on the PL, and if installed, the mold back and core back can assist in retracting the mold.

[0156] This mold structure can also be implemented in the case of GCP. It is also effective for molds with a back-chamfer structure (a mold structure of three or more plates) (such as stack molds), and just like with three-plate molds, springs, urethane rubber, etc. can be installed on the PL of each product surface so that they always open first when the die plate retracts. In this case, if a seal mold is used, GCP can be performed and a foam molded product with a smooth and clean surface without swirl marks and a high expansion ratio can be obtained by applying GCP. The mechanism for opening the PL first can also be implemented in a mold with a built-in hot runner. In this case, it is preferable for the hot runner to have an opening and closing mechanism (valve) such as a spring or needle type.

[0157] In the case of stack molding, generally, horizontal injection molding machines are also possible, but when injecting foamable resin from PL, injection molding machines with vertical clamping mechanism and horizontal injection mechanism (generally called vertical injection molding machines) are used. In this case, for stack molding of PL injection, shut-off nozzles with spring-type or needle-type opening and closing mechanisms are used. In this way, for foam molding products suitable for stack molding, the foam molding process is an effective means of increasing productivity, especially for flat shapes (flat plate shapes, shapes close to flat plates) such as IC trays used to transport semiconductors in semiconductor manufacturing plants. In the case of IC trays, conductivity is required, so conductive carbons such as Ketjen Black and acetylene black, carbon nanotubes (CNTs), etc. are added. Polymer alloys mainly composed of m-PPO and PC resins with high heat resistance are used for molding. PC resins may be used alone, and the type of resin is not important as long as the heat resistance requirement is met.

[0158] Usually, foam molding does not use holding pressure, or if it does, it is for a short time, so there is no need to precisely balance the filling of each molded product (cavity). It is sufficient to fill the cavity almost to the brim with foamable resin, or more than 70 of a cavity's volume being 100. A short mold is acceptable since mold back and core back will be used. Even if it exceeds 100, mold back and core back will occur, so the final volume will never exceed 100. Each cavity is filled with foamable resin at approximately the same time (the filling conditions are the same), but separate filling using sequential control is also acceptable.

[0159] The foam molding performed in this embodiment 5 is foam molding using an injection molding machine, and the properties of the substance that gives the resin foamability, the so-called foaming agent, can be applied to all of the following foam molding techniques: techniques that use gaseous substances, for example, compressed gas such as Mucel or Amotec, liquefied carbon dioxide, techniques that use liquid substances such as alcohol or water in NPT, microballoons, macroballoons, microballoons, bicarbonates such as baking soda, azo compounds such as ADCA, and nitroso compounds such as DPT.

[0160] In the case of IC trays, if a chemical foaming agent is used, there is a risk that the foaming gas and foaming residue will have a negative effect on the IC and the plated legs of the IC, so it is necessary to check thoroughly. There is no problem with foaming molding using gas or liquid, as the foaming residue will not be mixed into the molded product. In fact, the inventor used a mold for IC trays shown in Figure 10 (photo), m-PPO containing acetylene black as the molding resin, and water, ethanol, propanol, a mixture of water containing 40 wt.% ethanol, a mixture of water containing 40 wt.% propanol, and a mixture of ethanol and propanol in a 1:1 ratio as the foaming agent. Approximately 1 wt.% of the resin (molded product) was placed in a heating cylinder, vaporized to become a foaming resin, and foaming molding was performed without GCP, resulting in a weight reduction of about 6 to 10%. When GCP was used, the weight reduction was about 5 to 8%. The impact strength of each molded product was approximately 70% lower without GCP and only 25% lower with GCP, assuming the impact strength of the solid (solid, general, solid, general) molded product to be 100. The above examples were performed with m-PPO, but similar results are expected with PC resins. In this case, water is the most suitable blowing agent. In terms of heat resistance and cost, the molding material suitable for IC trays is preferably a conductive resin whose main component is m-PPO or PC resin, and when the heat resistance requirement is not so high, a conductive resin whose main component is a styrene resin such as ABS may also be used.

[0161] As a result of molding back 25% of the plate thickness (wall thickness) of the molded product, molded products without GCP and with GCP were obtained, with a weight reduction of about 25%. In this case, the impact strength of the molded product was further reduced, but this can be solved by adding graft rubber (a binary copolymer in which styrene is graft-copolymerized with butadiene rubber) contained in m-PPO in advance, assuming a decrease in impact strength. It is also possible to increase impact strength by increasing the particle size of the rubber, and in this case, using graft rubber with a different particle size will further improve impact strength. After the mold has been backed up, the mold can be closed a little again to compress it. After this, the mold must be opened and the molded product must be brought to the movable side (the side pushed out by the ejector pin), but depending on the shape, it may be taken to the fixed side. In this case, undercut or texture the side of the movable mold to ensure that it is brought to the movable side in a balanced manner.

[0162] The impact strength can be further improved by using EPDM {ethylene rubber (ethylene-propylene-diene monomer)} instead of butadiene rubber. EPDM has a much higher thermal stability than butadiene rubber, and m-PPO using EPDM graft rubber has high recyclability (there is little deterioration in physical and mechanical properties even if it is repeatedly recycled and subjected to heat history). When manufacturing m-PPO, PPO and rubber grafted with PS are melt-kneaded, but using a reduced volume of discarded polystyrene foam (the component is PS, and it is possible to use it because it is foamed using pentane, which does not leave a foaming residue), instead of PS, can contribute to reducing the environmental load. If necessary, a general foam nucleating agent or the foam nucleating agent of the PC resin described in this invention may be used. Since IC trays are made by mixing conductive materials such as acetylene black into m-PPO, acetylene black also acts as a foam nucleating agent. PC resin may be used instead of m-PPO.

[0163] Using the mold shown in Figure 10, a resin made by giving electrical conductivity to PC{SD Polycarbonate (product name) 301-15 (grade) instead of m-PPO was foam-molded using ion-exchanged water, and it was confirmed that foam-molding was possible in the same way as m-PPO, and that weight reduction was also possible. The conductive carbons such as Ketjen black and acetylene black, which impart electrical conductivity, acted as bubble nucleating agents. Trials with CNT also showed that CNT also acted as a foam nucleating agent, and therefore these conductive materials that impart conductivity are effective as foam nucleating agents for molded products that require conductivity, such as IC trays, and can therefore be used satisfactorily.

[0164] (Embodiment 6) In addition to mold backs and core backs, breathing (expanding) cores and dummy shapes are used to facilitate foaming. First, we will explain the expansion core. Figures 37 and 38 show an example of a dummy shape (a throw-away shape, a throw-away cavity) with a shutter. The shape is the opposite of a submarine gate. When resin is filled in the inside of reference number 4 and part or all of reference number 172 is filled with resin (Figure 37), the rod rod connected to the ejector plate of the mold reference number 168 retracts (Figure 38) immediately or after a certain period of time has passed. At that time, reference number 173 appears. Reference number 137 is connected to the dummy shape 171 from the gate reference number 170, so the molten resin in reference number 4, which has pressure (residual pressure), flows into reference number 171 through reference number 172, reference number 173, and reference number 170, and as a result, the pressure of the resin in reference number 4 decreases, making it easier to foam. Reference number 168 is a mechanism that moves using an ejector rod (for forward movement) and a spring (for backward movement) built into the mold, for example, in the same way as ejector plates (B) and (C). If ejector plates (B) and (C) are built into the mold, reference number 168 may be a new ejector plate (D). Ejector plate (D) may have a two-plate structure, one above the other, like (B) and (C), but it can also be a single plate since it is simply provided with a pin. Figures 37 and 38 show the reverse structure of a submarine gate (closed at first), but reference number 170 can also be implemented with other shapes.

[0165] (Embodiment 7) By using this rod structure and mechanism, automatic gate cutting can be easily performed in foam molding, blow molding, and pressure molding that do not use pressure holding. Figures 39, 40, and 41 show the structure of automatic gate cutting. Reference number 175 is the gate of the molded product of reference number 4, and its shape is a loading gate (Figure 39). Resin is filled into reference number 4, and immediately or after a certain period of time, when the rod rod connected to the ejector plate of the mold of reference number 177 advances, reference number 175 is pushed into the molded product of reference number 4 (Figure 40). As a result, the spool runner and gate are separated from the molded product 4 (Figure 41). In this case, there is no limit to the height or width of the gate, and in the case of a wide gate, a plate wider than the gate width can be used, with the tip of reference number 177 adjusted to the gate width. In blow molding and pressure molding, automatic gate cutting prevents backflow of the pressurized fluid injected into the spool runner. There are no restrictions on gate width for automatic gate cutting in foam molding, blow molding, pressure molding, etc., and the latitude of molding conditions is greatly expanded. Since holding pressure is not used in foam molding, blow molding, and pressure molding, and even if it is used, it is only for a short time, automatic gate cutting shown in Figures 39 to 41 can be easily implemented.

[0166] Next, we will show a method for reducing the pressure of the molten resin filled in the cavity to facilitate foaming in foam molding using a dummy shape (a throwaway cavity) without a shutter. In Figure 42, the shapes indicated by 181 and 182 are dummy shapes connected by reference number 180. Part of the dummy shape is filled with resin (reference number 181), and the part indicated by reference number 182 is actually filled, which is a so-called short mold, so the pressure of the filled resin in reference number 4 is reduced and foaming occurs easily, resulting in a foam molded product with a high expansion ratio.

[0167] In the case of blow molding and pressure molding, the dummy shape indicated by reference number 183 must be fully filled (fill the space of 183 with resin). In the case of blow molding, the pressurized fluid put into the molded product advances toward the part with low pressure, so if reference number 183 is a short mold like reference numbers 181 and 182, the pressurized fluid will escape from there and sufficient hollow space cannot be formed. Pressure molding is a molding method in which pressurized fluid is put into the gap between the resin and the mold and the other side is pressurized with that pressure. In this case, too, if reference number 183 is a short mold, the pressurized fluid will escape from the end of the short mold, so sufficient pressurization effect cannot be expected. The dummy shapes indicated by reference numbers 181, 182, and 183 are more suitable for the purpose of reducing pressure if they take a longer time to cool and solidify, so the thickness of this part is often made two or three times thicker than the thickness of reference number 4.

[0168] (Embodiment 8) Super engineering plastics such as PPS (polyphenylene sulfide), PES (polyethersulfone), and PEI (polyetherimide) are thermoplastic resins with high melting temperatures. When foam molding is performed using low boiling point solvents such as ethanol (ignition point temperature at 1 atm pressure is about 400°C) and iso-propanol as a blowing agent, if the ignition point of these liquids is higher than the temperature of the molten resin, there is a risk of fire, and discoloration and burning of the resin are expected. In other words, nitrogen gas replacement is performed in the hopper. Also, if air is used for the outer GCP, the temperature of the resin is still high, and if the temperature rises further due to adiabatic compression, discoloration and burning of the resin are a concern, inert nitrogen gas can be used instead of air for pressurization. Carbon dioxide is fine.

[0169] (Embodiment 9) Foaming agents that are insoluble in water or alcohol, such as ADCA powder and HDCA powder, will precipitate (sediment) if simply placed in water or alcohol, due to their low viscosity. In order to slow down the rate of precipitation as much as possible, a varnish with increased viscosity is used in combination. If the resin to be foamed is PP, a solvent-based or water-based varnish for maleic acid-modified PP is used. If the resin to be foamed is ABS, for example, a varnish made from AS or ABS using a solvent (e.g., n-butanone) is used, and if the resin to be foamed is HIPS, a varnish made from PS or HIPS in the same manner as AS or ABS is used. In the case of styrene-modified acrylic resin varnish, both ABS and HIPS can be used. If a low-boiling point solvent is used, the inside of the hopper is replaced with an inert gas as shown in embodiment 8.

[0170] (Embodiment 10) The water holes (cooling circuits) of the mold used in the present invention will be explained. Generally, water holes are opened using a gun drill, but since they are straight and curved, the heat exchange rate is not so high. By using heat bonding {Yamatec Co., Ltd. 3-3-5 Mizuho-cho, Nishitama-gun, Tokyo 190-1232 TEL: 042-557-5660} and heat melt bonding, a water circuit with a high heat exchange rate can be created. Specifically, an optimal cooling circuit is created on the surface, for example, with a milling cutter or by electric discharge machining. This is called the first insert. Next, a insert with a shape to cover the first insert is machined. This is called the second insert, and the first insert is covered with the second insert, and the surfaces are joined using heat bonding or the like to create a curved water circuit inside. The shape of the insert and the optimal flow path of the water hole are designed (calculated) in advance using CAD or the like. A water circuit is created in the hexahedral first mold before the insert is shaped, and also in the hexahedral second mold as necessary, and then a hexahedral body with a water circuit inside can be made by heat bonding. This hexahedral body can then be used to machine the shape designed in advance using CAD using conventional means. The reason why the first insert and the second insert are made hexahedral is that the bonding strength is increased if the bonding surfaces have as high a surface accuracy as possible (for example, polished surfaces are better than milled surfaces). Although a hexahedral shape is used in the tenth embodiment, the shape is not limited to this.

[0171] (Embodiment 11) (Nitrogen gas is generated as a foaming agent in liquids) Compounds that generate nitrogen gas with high foaming power include azides such as sodium azide (NaN3), azo compounds such as ADCA, and nitrosates such as DPT. Inorganic sodium azide is water-soluble, but NaN3 begins to decompose when dissolved in water, so aqueous solutions of sodium azide cannot be stored for long periods and are therefore not suitable as liquid foaming agents. ADCA derivatives that are soluble in alcohol include esters of ADCA, such as ADCA diethyl {DEAD(CH 10 There is a DEAD (N2O4) which can be used as a liquid foaming agent. ADCA isodipropyl (DIAD) is also soluble in ethanol, and an alcohol solution of DIAD can be used as a liquid foaming agent in the same way as the alcohol solution of DEAD mentioned above. Simply putting ADCA powder in alcohol such as ethanol and pulverizing it using a mill or the like will create a slurry, which can be used as a liquid foaming agent that generates nitrogen gas in the foaming gas containing ADCA.

[0172] Polyvinyl alcohol (PVAL) is compatible with thermoplastic resins due to its molecular structure. Polyvinyl butyral (PVB) is a thermoplastic resin that exhibits high adhesion to glass, metal, ceramics, etc., and is compatible with thermoplastic resins. Both (PVAL, PVB) can be used to create a highly viscous liquid using alcohol and water, so if ADCA powder is dispersed in these, it becomes a slurry containing ADCA, which becomes a liquid foaming agent.

[0173] If maleic acid-modified PP varnish is thickened and ADCA powder is suspended, it becomes a liquid blowing agent for PP, and if ADCA powder is suspended in styrene-modified acrylic resin varnish, it becomes a liquid blowing agent for styrene-based resins such as HIPS and ABS. To thicken these maleic acid-modified PP solutions and styrene-modified acrylic resins with ADCA slurries, the thickener carboxymethyl cellulose (CMC) can be used. In addition to ADCA, air bubbles can also be dispersed. Naturally, inorganic hydrogen carbonates such as sodium bicarbonate can also be used. Cellulose nanofibers (CNF) can also be added to thicken the mixture. CNF also acts as a foam nucleating agent in foam molding.

[0174] The chemical structure of ADCA shows that two molecules of urea can be combined. When combined with urea, this substance may become water-soluble, since urea is water-soluble. If it is water-soluble, it can be used as a liquid foaming agent, and it will decompose thermally in the same way as ADCA, generating nitrogen foaming gas.

[0175] (Embodiment 12) In the two-cavity, paired molding of Example 20, the foamable resin can be filled into each cavity at once, or separately. The method of filling the paired molding and separate filling is explained below. Let's assume that the molded products are A and B, and the amount of resin to be filled into A and B is measured in advance. First, fill molded product A, then switch the gate and fill B. When A and B have finished cooling and solidifying, the mold is opened and each molded product is removed at the same time. First, the amount of molded product A is measured and filled into the cavity of A. After filling is completed, the amount of molded product B is measured again, and the gate is switched and filled into B. When A and B have finished cooling and solidifying, the mold is opened and each molded product is removed at the same time. When this molding method is used, the mold closing, cooling inside the mold, mold opening, and ejection (pushing out the molded product) are common, so the molding cycle is increased and productivity is improved. This method can also be implemented in the case of the blow molding of Example 21 and Example 22. After filling the cavity with foamable resin or non-foamable resin, the mold is closed and compressed, and then mold back or core back may be performed as necessary. The IC tray shape can be used as a so-called cassette mold, which allows the inserts of the molded product to be replaced while the mold is still attached to the molding machine in order to reduce mold costs. In this way, when switching between A and B molding, in addition to the mechanism for switching the gate, a valve-gate type hot runner can be used to open and close the valves respectively. This filling for switching between A and B is performed by a program in the molding machine's sequencer.

[0176] The foam nucleating agent for PC resin explained in this invention is used for extrusion foam molding using PC resin. The foaming agent used in this case is most preferably liquid water.

[0177] (Embodiment 13) The thirteenth embodiment shows the main problems of plastic recycling and the means of solving them. There are many technical challenges in plastic recycling, but the main ones are "color recycling", "restoring or maintaining physical properties", "reproducing dimensions", and "sorting". First, we will explain "color recycling". Plastics have low mechanical strength, but they are characterized by being inexpensive and mass-produced, and being able to be colored freely. This ability to be colored freely means that plastic products of various colors are offered on the market, so the color problem, that is, color reproduction, is one of the challenges that prevents plastic recycling from progressing. There are two means of recycling this color. One method is to collect only objects (molded products) of the same color, wash them, crush them, mix the crushed material with virgin pellets or powdered objects, re-pelletize them, and obtain a molding material with a certain amount of recycled material mixed in (about 10wt.% to 50wt.%). In this way, colors can be reproduced, but it is a means of recycling only plastic molded products of a specified color.

[0178] (Cleaning Method) Molded products collected from the market are often dirty and have been photodegraded by ultraviolet rays and other factors, resulting in discoloration. In such cases, the photodegraded parts (mainly the surface) are removed using shot blasting or other methods. The molded products are washed by placing them in water and scrubbing them with hands, or by inserting an ultrasonic vibrator and performing ultrasonic cleaning.

[0179] When a molded product is crushed in a crusher, sound is produced. A wet crusher is a crusher that utilizes this sound. When crushing is performed while injecting water or underwater, sound is produced (generated), and this sound is transmitted underwater, and dirt on the molded product surface is washed away by physical force (sound waves).

[0180] (Recycling colors using paint) When there are molded products of various colors, they are not color-sorted, but are crushed as they are, and the molding material is pelletized as necessary. The molding material is then molded as it is in the various colors, and the surfaces of the molded products obtained by molding the various colors can be painted to recycle them into molded products of the desired color. When using paint for coloring (decorative paint, cover mark paint), for example, if the resin that makes up the molded product is ABS, HIPS, or modified PPO, paint whose main component is styrene-modified acrylic resin that is compatible (soluble) with the resin that makes up the molded product is used. When a molded product with a coating film painted using the above-mentioned compatible paint is recycled, the coating film is not separated or peeled off, but is crushed with the coating film still attached, and if necessary, when the molded product is molded using pelletized molding material, the styrene-modified acrylic resin, which is the main component of the coating film, is compatible with the resin that makes up the molded product and melts into the resin at the pelletizing stage and / or the heating and melting stage of remolding, so there is less deterioration in the physical properties of the resin caused by the coating film mixing.

[0181] Since the styrene-modified acrylic resin is a resin that exhibits thermoplasticity, paints using this resin have low chemical resistance, and the coating film peels off in a rubbing test using alcohol, for example. When chemical resistance is required, paints whose main component is urethane resin (the urethane resin in the coating is thermosetting, while styrene-modified acrylic resin is thermoplastic) are often used, and although it is best to separate and peel off the coating of painted molded products that have been painted with paints whose main component is urethane resin, if the coating is not separated or peeled off and the product is pulverized with the coating still on, and then refined (for example, to an average particle size of 1,000μm or less, preferably 100μm or less) using an extruder capable of high-intensity kneading such as a twin-screw extruder or kneader, then the physical properties will not decrease significantly even if the urethane coating is mixed into the molding resin. In some cases, there may be no decrease compared to thermoplastic styrene-modified acrylic resin (in the case of styrene-modified acrylic resin, the dyes and pigments in the coating melt during the pelletizing and remolding stages, migrating into the resin and reducing the physical properties of the resin, but in the case of urethane resin, since it does not melt, the dyes and pigments in the coating remain in the coating and do not migrate into the resin, so there is less decrease in the physical properties of the resin).

[0182] The extruder with strong kneading may be a single screw, but preferably a multi-screw extruder (two or more) with one or several screws with dulmage. The screws may rotate in the same direction, but to improve kneading and refine the urethane coating, it is better to rotate them in opposite directions. PP is used extensively in automobile parts, so to paint PP molded products, a primer treatment is first performed using maleic acid-modified PP, and then a paint using a thermosetting urethane resin is used.

[0183] (Restoration of physical properties) In order to improve the physical properties of styrene resins such as ABS and HIPS, rubber that has been grafted with the resin components to be blended is blended. We will explain using ABS. ABS is a blend polymer made by blending (mixing) AS resin, which is a copolymer of A (vinyl cyanide) and S (vinyl phenylate), with a tertiary graft copolymer of A, S, and butadiene rubber, which is a graft copolymer of A and S grafted onto butadiene rubber. When ABS is molded, crushed, and remolded, the butadiene rubber in the tertiary graft copolymer of A, S, and butadiene rubber (brown butadiene rubber) undergoes thermal degradation and loses its rubber properties. As a result, repeated recycling reduces the physical properties of the resin, such as impact strength. The deteriorated physical properties of the resin can be restored by mixing in new grafted butadiene rubber. If the addition of grafted butadiene rubber reduces the rigidity of the resin, AS resin is mixed in to balance the resin and then recycled.

[0184] (Maintaining physical properties) ABS has low weather (light) resistance due to butadiene rubber. AAS (ASA) and AES, which use acrylic rubber (AR) and ethylene propylene rubber (EPM, EPDM) instead of butadiene rubber, do not experience significant deterioration in physical properties like ABS, even if recycled repeatedly. As a simple means of confirming recyclability, the inventors used an injection molding machine equipped with a shut-off nozzle, set all zone temperatures to 220°C, and set the temperature of the molten resin to 250°C, melted and mixed the resin, and allowed it to remain in the heating barrel for 30 to 60 minutes to apply thermal stress to the molten resin in the heating barrel. After a specified time (e.g., 30 minutes) had passed, the resin was purged, the purged mass was submerged in water to cool, and the purged mass that had been cooled was crushed, and the crushed material was used to mold test pieces for evaluating physical properties, and the physical properties were evaluated (this means is called the "thermal degradation test" in this invention). As a result, the Izod impact strength was 0% to 5% for AES and less than 10% for AAS, but a significant decrease of more than 50% was confirmed in the case of ABS.

[0185] Similarly, in the case of PE (polyethylene), the retention test showed almost no decrease in Izod impact strength, which was almost the same as that of virgin material, and no significant decrease in physical properties was confirmed. PE has high thermal stability and can be said to be a resin suitable for recycling.

[0186] In the case of PP (polypropylene), based on its molecular structure, there is syndiotactic PP, isotactic PP, and atactic PP. Furthermore, the catalysts used during polymerization include Ziegler-Natta catalysts and metallocene catalysts. When thermal degradation tests were conducted on each of these, the reduction in Izod impact strength was only about 5% for all types of PP, and it was concluded that PP has high heat resistance and is a resin suitable for recycling.

[0187] Just as the surface of a molded product is always wet by absorbing moisture from the air, a permanently antistatic resin made by mixing polyetheresteramide with ABS (Toray Industries, Inc.'s PAREL (product name)) showed a drop in Izod impact strength of nearly 90% in heat degradation tests, so PAREL is not a suitable resin for recycling.

[0188] (Recycling aid) "Recycling aids" are materials and additives that restore recycled materials to their original physical properties. Resins that are added for the purpose of modifying properties to give them different properties are also recycling aids. For example, the impact strength of ABS decreases when recycled. In this case, adding half the same ABS can restore some of the physical properties. ABS, which is developed to reduce the impact of recycled materials, and the aforementioned AS are both recycling aids. AES has high thermal stability, so if AES collected from the market is mixed with recycled ABS, the physical properties of the ABS can be restored. In this case, AES is also a recycling aid in the broad sense, and HIPS, which is used to modify EPS, is also a recycling aid. In this way, the original resin and resin additives are defined as recycling aids in this invention. Paints used to restore color (such as cover marking molded products to a different color) are also recycling aids.

[0189] (Maintain dimensions) When recycled resin is subjected to heat history, some of the molecular chains are broken and become low molecular weight.Otherwise, if a recycling aid is added to restore the physical properties, the fluidity of the molten resin changes, so in injection molding, with the general injection molding method (a molding process in which molten resin is filled into the cavity and then pressure is applied to eliminate defects in the molded product such as sink marks), there is a large variation in dimensions (variation in molding shrinkage rate) and the dimensions are not stable like when virgin materials are used, and in the case of recycled materials, there is a large variation in dimensions and they are not stable. To solve this problem, if the molding methods that do not use pressure holding are used, such as foam molding (injection foam molding), blow molding (injection blow molding), and pressure molding (injection pressure molding), and if the main components (molecular structure) of the resin to be molded are the same, the molding shrinkage rate of the recycled material will be roughly the same as when foam molding, blow molding, or pressure molding is performed using virgin material, so when recycling, it is better to use foam molding, blow molding, or pressure molding rather than general molding.

[0190] (Sorting) When recycling, complete recycling is not possible unless it is possible to accurately determine what resin is used in the molded product to be recycled and what types and amounts of additives are blended into that resin. Below we will provide a detailed and concrete explanation of the preparations that need to be made in advance for recycling (sorting).

[0191] First, we will explain the resin that is the main component of the molded product, using ABS as an example. As mentioned above, ABS is a blend polymer, or polymer alloy, made by mixing a copolymer of A and S with grafted butadiene rubber. Here, AS can be manufactured into resins with various ratios depending on the polymerization ratio of A and S (A to S ratio). Naturally, resins with different molecular weights (e.g. number average molecular weight, average molecular weight, etc.) are manufactured depending on the polymerization initiator and polymerization terminator, and there are differences in the molecular weight distribution. Even butadiene rubber has differences in the ratio of A to S and grafting rate. Various particle sizes (bimodal type) are used for the grafted butadiene rubber that is mixed with AS. In this way, various types of ABS alone can be manufactured.

[0192] (Other additives) As mentioned above, dyes and pigments are used for coloring ABS. If flame retardancy is required, flame retardants (such as halogen-type or non-halogen-type) and flame retardant assistants are added. In addition, antioxidants, antioxidants, antiozonants, UV absorbers, light stabilizers, plasticizers, fillers, reinforcing agents, PVC stabilizers, lubricants, slip agents, internal mold release agents, anti-fog agents, antistatic agents, colorants (including the above dyes and pigments), coupling agents, preservatives, mold inhibitors, compatibilizers, modifiers, crystal nucleating agents, dispersants, light diffusing agents, and bubble nucleating agents in the case of foam molding ("resin additives" or simply "additives") are used as necessary, as described in the "Handbook of Rubber and Plastic Compounding Chemicals, Second Revised Edition {Rubber Digest Co., Ltd., Second Revised Edition, October 30, 1993}." These additives may be usable when the molded products containing these additives are processed and delivered to the market, but may be substances that should not be mixed in when they are collected from the market and recycled several years later. Let's take flame retardants as an example. In the past, flame retardants were generally made by using halogen compounds that use the negative catalytic action of halogens, such as brominated epoxy and TBBA (tetrabromobisphenol A derivative), and antimony trioxide as a flame retardant assistant, but these days, their use is being refrained from due to the problem of the generation of brominated dioxins and brominated benzofurans. Antimony trioxide is a hazardous substance, so its use is hesitant. When recycling today, if halides are contained like this, it is necessary to recycle separately.

[0193] However, as mentioned above, it is not possible to reliably grasp the information (type of resin, additives, etc.) necessary to implement recycling (equivalent recycling, higher-level recycling) just by looking at the molded product, so the resulting recycling ends up being lower-level recycling.

[0194] (display) As mentioned above, it is difficult to grasp the huge amount of information required for recycling only from the mandatory recycling mark, so the inventors have inscribed a barcode {: normal barcode, two-dimensional barcode (QR code)} on the mold in advance for molded products with a certain weight, for example, 100 grams (g) or more. The barcode contains the weight of the molded product required for recycling, information on the resin that is the main component of the molded product as mentioned above using ABS as an example, such as molecular weight, ratio of A to S, information on the additives mentioned above (type and amount added), and the weight of the molded product. A useful method is to write this information on the molded product, collect it from the market, and read it at the recycling stage, for example before washing or before crushing, and at the recycling stage, crush it after confirming that it does not contain any prohibited substances at the current time. Molded products that contain prohibited substances are not crushed and are stored in a separate location.

[0195] Since the amount of information is enormous, it is given to each molded product as a barcode, preferably a QR code (two-dimensional barcode). QR codes are preferable to barcodes because they can hold more information. A label (sticker) with the QR code printed on it is affixed. Alternatively, in the case of injection molded products, the QR code can be engraved into the mold beforehand, eliminating the need to affix a label (Figure 44). In the following, the present invention will be described using a QR code (see FIG. 48, reference number 206).

[0196] The information in the QR code is read by a barcode reader, and when the crushed material is crushed, it is possible to know what kind of resin and how much of the additives are contained in the crushed material after crushing. If this can be done, it is easy to use a computer, for example, AI (Artificial Intelligence), to add the necessary additives in the necessary amounts to modify the material. The previously mentioned QR code is displayed on the molded products made from the recycled material obtained in this way, with the next recycling in mind. This allows recycling to be repeated (meaning repeating the recycling generations {1st (1st turn), 2nd (2nd turn), 3rd (3rd turn), etc.}). Of course, the QR code information also includes the content (mixture ratio, etc.) of the 1st turn material and the 2nd turn material. In other words, the necessary information is always added as a preparation for future recycling. This allows future recycling to be carried out without any problems.

[0197] (Confidentiality) For example, the name of the resin manufacturer, the product name, the grade, and the detailed composition of the resin (such as the type and amount of additives) can be read from the QR code, so there is a risk that important confidential information of the resin manufacturer may leak to competitors, and this is not desirable as it is. To do this, it is necessary to encrypt part or all of the content contained in the QR code (for example, a combination of numbers and letters using prime numbers, etc.). The encrypted content is only stored within the AI, such as the type of resin, the type and amount of additives, and the weight of the crushed material (the total weight of the crushed molded products is the weight information of the molded products written in the QR code, or the weight of each molded product is automatically measured and entered into the AI.), and the AI ​​and the person operating the AI ​​(such as an operator) must be required to impose necessary security measures to ensure that this information is never leaked to other companies.

[0198] (Recycling) Specifically, all recycling and resin modification is done within the AI. The AI ​​checks and understands all information related to the resin and additives of the crushed material for recycling purposes, so if you instruct the AI ​​on what kind of resin properties the crushed material should be modified into, the AI ​​will perform calculations and calculate the type and amount of resin and the type and amount of additives (type and amount of recycling aids, etc.) that need to be recycled. The type and amount of resin and the type and amount of additives calculated by the AI ​​are added to the crushed material in advance, and test pieces are molded and processed, and the physical properties are measured (quality control), and it is confirmed whether the results match the contents calculated by the AI ​​(the planned physical properties of the recycled material). If the results are good, the type and amount of resin and the type and amount of additives required for recycling are added, and the recycled material is manufactured using the necessary means (for example, a multi-screw extruder with short shafts, screws rotating in the same direction, and counter-rotating screws, melt kneading with kneader processing, pelletization, etc.). The obtained recycled material is sampled to measure its physical properties, and these are compared with the physical properties confirmed before production to confirm whether the recycling has been completed to the desired physical properties.

[0199] ("Equivalent reproduction", "upper reproduction", and "lower reproduction".) For example, using the casing (molded product) of an office equipment printer to recycle it into the casing of the same office equipment printer is called "equivalent recycling." Recycling (remanufacturing) using something of equal value (the printer casing) to recycle it into something of equal value (the printer casing) is called "equivalent recycling." Since the main component of expanded polystyrene (for example, EPS) is PS (GP), it can be modified to HIPS (high impact polystyrene) by reducing the volume, crushing it, mixing it with butadiene rubber made by grafting styrene with butadiene rubber, and pelletizing it. In this way, using a low-grade material such as EPS and modifying it with HIPS to make a higher-grade HIPS that is more valuable than EPS is called "high-grade recycling." By mixing this HIPS with PPO (polyphenylene oxide) and adding a flame retardant, it is possible to produce the same Noryl (brand name) using EPS. However, currently, management is not carried out using the QR codes and other methods described in this invention, and the resins and additives in the molded products are not known. Therefore, the resins are simply crushed without being separated into different types, and when they are used as resins to process artificial wood, flower pots, etc., this is called "lower-level recycling." Since molded products collected from the market are combustible, if they are recycled as fuel in cement factories, steel mills, thermal power plants, etc. to produce thermal energy (a lower-level type of energy), this is considered lower-level recycling and will be a one-time process. This is also "lower-level recycling."

[0200] (Recycling method flow) The actual flow of plastic recycling using this invention is shown below. Virgin resin is used for molding, and painting is applied as necessary. Molded products marked with QR codes are supplied to the market, and are collected once their role is completed. The QR codes and other methods shown on the molded products are used to check whether they are recyclable and whether they contain any substances that inhibit recycling. Recyclable molded products are washed as necessary, or any deteriorated surface areas are removed using blasting or other methods.

[0201] When items of the same material and color are collected, they are crushed, the necessary recycling aids calculated by AI are added, and the items are tumbled to make them uniform, pelletized, and reused as recycled material. In this case, the amount of recycled resin contained, the amount of each additive, and the amount of recycling aid are recorded on the molded item using a QR code or similar, since the molded item will be recycled again in the future.

[0202] Even if they are not color-coded and are crushed as they are, with the QR code, only those molded products that are judged to be recyclable are crushed, and the AI ​​checks the type of resin and the type and amount of additives contained in the crushed material, and in the same way, recycling aids and other additives are added, tumbled, pelletized, and remolded. The resulting molded products can be used as they are, with mixed colors, but if coloring is required, they are painted as a cover mark. Of course, this molded product is engraved with a QR code that contains information on the type and amount of recycling aids and other additives, including the fact that it has been painted, with the assumption that it will be recycled using the QR code.

[0203] In this way, by using a QR code on a molded product and providing the information necessary for recycling to the molded product, recycling becomes easier. Even if recycling is carried out again, the QR code provided on the molded product ensures that the product can be recycled. In cases where a mold is not used, such as vacuum molding, it is not possible to imprint the molded product, so for example, the QR code can be silk-screened or a sticker with a QR code printed on it can be affixed. Of course, information such as the ink used for silk-screen printing and the material of the sticker are also written into the QR code.

[0204] (Embodiment 14) In recent years, interest in biomass plastics has been growing amid rising interest in prefectural border issues. In the fourteenth to twenty-eighth embodiments, specific means and methods for producing resin pellets used in processing resins containing environmentally degradable components that undergo biodegradation in nature through the power (action) of bacteria, photodecomposition through ultraviolet light, and hydrolysis through water, and that are mainly thermovisible and thermosetting, are shown, as well as details of extrusion molding, injection molding, and other necessary equipment using the resin pellets, and means for preventing discoloration and burning.

[0205] (mixing device) In this invention, the device that mixes each material is called a "mixing device." Common examples of mixing devices include tumblers, Henschel mixers, and rocking mixers, but any device that is used for the purpose of mixing each material is acceptable. There are no restrictions on the means or structure. A concrete mixer can also be used. In this invention, mixing using a tumbler is called "tumbling." It is preferable to use a weight control device, weight control feeder, weight feeder, etc., such as a Backmelter (product name) shown in the embodiment described later (see Figures 45 and 46, reference numbers 187 and 188).

[0206] (Dust explosion) Environmentally degradable components and substances such as cellulose powder, paper powder, wheat flour, bran, and wood powder are flammable fine powders, so there is a risk of dust explosions. The air inside the mixing device is replaced with an inert gas, such as nitrogen gas, before each material is placed in the device and mixed. A specific explanation will be given using a tumbler. The air in the tumbler is replaced with nitrogen gas, and cellulose powder, thermoplastic resin, and other additives, if necessary, are placed in the device, and the tumbler is rotated to mix. The same is true for the Henschel mixer; the inside of the mixer is replaced with nitrogen gas beforehand, and then each material is added and mixed. Even during the mixing stage, nitrogen gas should continue to be added as necessary. The environmentally degradable component of the present invention may be used in one kind, but if necessary, several kinds may be mixed and used, which is expected to improve quality and provide economical benefits.

[0207] (Tumbler) It is common to mix the thermoplastic resin and the environmentally degradable component in a tumbler before pelletizing. This mixture naturally contains air. In particular, the environmentally degradable component is in powder form, so it is particularly prone to containing air. Naturally, air contains about 20% by volume (about 23% by weight). If the mixture is pelletized in this state using a kneader (including pressure kneaders), Banbury mixer, single-screw extruder, or multi-screw extruder, the oxygen will oxidize the environmentally degradable component or some of the components in the environmentally degradable component, such as lignin, and cause discoloration. To solve this problem, an inert gas is introduced into the tumbler to reduce the oxygen concentration. Lignin can be removed, for example, by washing with water and / or an organic solvent, by raising the temperature of the water and / or the organic solvent, by boiling in hot water, or by washing with steam. When washing with steam, the environmentally degradable components absorb water, making it possible to reduce their volume. When washing with water, the components also absorb water. By reducing the volume in this way, operations such as melting and kneading in a tumbler are made easier.

[0208] (Melting and kneading equipment) In the present invention, a device that heats, melts, and kneads the thermoplastic material among the mixed materials is called a "melt kneading device." Examples of such a device include a single-screw (one-screw) or multi-screw (e.g., two-screw) extruder, a heatable kneader, a heatable Banbury mixer, and a heatable roller. However, before being fed into the melt kneading device, there is a risk of dust explosion, so measures such as nitrogen gas replacement are required. For example, when melt kneading is performed using a twin-screw extruder, which may rotate in the same direction or in different directions, in addition to dust explosions, for example, when cellulose powder colored in a desired color, such as white (several types of environmentally degradable components may be mixed in), is mixed with a thermoplastic resin and melt kneaded, the environmentally degradable components will discolor or burn, and the desired color will not be obtained. If colored, the intended color will not be achieved. This is because when melt kneading a thermoplastic resin in an extruder heating tube, even if the resin used is PP, it is heated to nearly 200°C. At this temperature of 200°C, for example, if an environmentally degradable component is used, it will discolor to yellow or brown. In some cases, if the temperature of the melt kneading is increased, it will burn to black. This discoloration and burning problem is caused by oxygen in the air, and discoloration occurs in an atmosphere where oxygen is present. In inert gases such as nitrogen gas, carbon dioxide gas, and rare gases, discoloration is minimal. Or there is no discoloration at all.

[0209] As a means for solving the problem of discoloration, the inventor replaces the inside of the hopper with nitrogen gas, for example, when using an extruder for pelletization, sheet molding, etc. Specifically, by replacing the inside of the hopper with nitrogen gas and injecting nitrogen gas into the vent part of the extruder, the nitrogen gas also enters the heating cylinder, preventing discoloration.

[0210] Even when the nitrogen-substituted mixture (mixture 001 in which the air in the gaps has been replaced with nitrogen gas) is melt-kneaded using a kneader, Banbury mixer, single-screw mixer, or multi-screw extruder, there is a risk of discoloration due to oxidation if oxygen gets in. Now, melt-kneading using a single-screw or multi-screw extruder will be explained. It is preferable to replace the air in the hopper of the extruder with nitrogen gas before putting the mixture into the hopper. The mixture to be melt-kneaded and pelletized (tumbled and nitrogen-substituted) is placed in the hopper, and nitrogen gas is continuously introduced into the hopper. In the present invention, this is called sealing the hopper with nitrogen gas. Nitrogen gas should be injected into the hopper and sealed so that it comes out from the bottom of the hopper, just before the heating cylinder, inside the hopper, and preferably from the center of the material, as shown in Figures 45 and 46. Nitrogen gas (reference numbers 187 and 188) below the hopper is sent from the hopper to the heating cylinder together with the mixture 001.

[0211] (Discoloration / burning) Environmentally degradable components and thermoplastic resins do not cause any problems at room temperature, but when they are heated to high temperatures, for example to nearly 200°C, and come into contact with air, they are oxidized by the oxygen in the air and turn yellow or brown. If the oxidation progresses further, they become burnt. In this invention, discoloration and burning are collectively referred to as "discoloration, etc." or "discoloration / burnt."

[0212] (molding equipment) The term "molding equipment" refers to an extruder, a sheet extruder, a profile extruder, an injection molding machine, a block molding machine, a casting machine, a calendar molding machine, a blow molding machine, etc. Products processed using a molding equipment are called "molded products, molded products, molded products." In the present invention, pellets of the raw material are also included in the molded products.

[0213] (cooling device) "Cooling equipment" refers to conveyors for air-cooling the thermoplastic resin strands coming out of the extruder, water tanks for water-cooling, temperature regulators that control the temperature of the molding machine, chillers, etc. In the case of sheet molding, it also refers to conveyors, water tanks, etc. that cool the sheet.

[0214] (Molding equipment) "Molding equipment" is a general term for extruder dies, molds for casting processing, molds for injection molding processing, etc.

[0215] (Molding method) The "molding method" referred to in the present invention refers to extrusion molding, profile extrusion molding, cast molding, injection molding, block molding, calendar molding, and the like, which are used to produce strands or sheets. In particular, injection molding includes not only general molding methods (general molding methods, normal molding methods), but also injection foam molding using a chemical foaming agent whose properties are solid, liquid, or gas, injection foam molding using a physical foaming agent whose properties are solid, liquid, or gas (also simply referred to as "foam molding, or foam molding method"), extrusion molding, profile extrusion molding, cast molding, block molding, calendar molding, and the like, which use the above-mentioned foaming agents. Simpress (product name), AGI (product name), Air Mold (product name), and its applied technology RFM, H 2 Injection blow molding methods such as the M molding method (which are also referred to simply as "blow molding" or "blow molding methods" in the present invention), and injection pressure molding (which is also referred to simply as "pressure molding" or "pressure molding method") in which a gas having a pressure equal to or higher than atmospheric pressure is introduced into the gap between the molten resin and the mold and pressure is applied by the pressure of that gas can also be carried out using the resin containing the environmentally degradable component of the present invention.

[0216] (inert gas) The term "inert gas" refers to a gas that contains an environmentally decomposable component and does not oxidize a molding material containing a thermoplastic resin when the actual temperature of the molding material is 380°C. Examples of such gases include nitrogen gas, carbon monoxide, carbon dioxide gas, hydrogen gas, gas obtained by vaporizing an organic solvent, and rare gases such as helium and neon. These gases are used alone or mixed together to form a composite gas. Particularly useful gases in the present invention are nitrogen gas and carbon dioxide gas. In particular, nitrogen gas is used frequently in the present invention because it can be obtained in large quantities at low cost using a separation device such as a separation membrane or PSA. In addition, oxidation in the present invention refers to bonding with oxygen and decomposition by oxygen, as well as the loss of electrons by the target substance.

[0217] (Gas replacement) "Gas replacement" refers to the process of reducing the pressure and degassing the oxygen-containing air that has entered the device and / or the gaps in the materials, and then introducing an inert gas, such as nitrogen gas or carbon dioxide gas, under reduced pressure, and then raising the pressure back up to atmospheric pressure. Instead of reducing the pressure, it is also possible to introduce an inert gas and then pressurize. For example, an inert gas with a pressure equal to or higher than atmospheric pressure is introduced and replaced with the air. This method can be done once, but repeating it several times will ensure sufficient replacement. The air in the hopper of the extruder or injection molding machine, and the air in the gaps between the materials, can be reduced in pressure, pressurized with the gas to be replaced, reduced in pressure, and pressurized with the gas to be replaced, repeatedly. Since equipment optimal for this method, such as a back melter (Back Melter) (product name), is available, gas replacement can be easily performed. It is also possible to simply perform a vacuum (which actually means to reduce the pressure) using Haruna Co., Ltd.'s Eco Mac (product name). The inert gas can be introduced again into the vacuum device. In this invention, devices with functions such as a back melter and Eco Mac are collectively referred to as "back melters". The pressure may be increased to above atmospheric pressure without reducing the pressure in the back melter, returned to atmospheric pressure, and then increased to above atmospheric pressure again for replacement.

[0218] The mixture of environmentally degradable components and thermoplastic resin mixed in a tumbler is placed in a closed container, and a vacuum is drawn using a vacuum pump or the like. When inert nitrogen gas is poured into the reduced pressure, the air (especially oxygen) in the tumbled material is replaced by nitrogen gas. This process of replacing air with nitrogen gas can replace as much oxygen as possible with nitrogen gas even in one go, but if further replacement with nitrogen gas is desired, it is preferable to carry out the process multiple times.

[0219] (Gas sealing) "Gas sealing" means, for example, that after air has been expelled and replaced with inert nitrogen gas, in order to prevent air from re-entering, nitrogen gas is continuously or intermittently pumped into an apparatus, such as the hopper or feed screw (subscrew) of an extruder, to create an atmosphere of only inert gas inside the apparatus.

[0220] {Gas Under Pressure (GCP), GCP method, outer GCP} "Outer GCP" is a method for obtaining a foamed product with a smooth and beautiful surface without swirl marks in foam molding. Normally, air pressurized to a pressure higher than atmospheric pressure is used, but as mentioned above, discoloration and burning are significant when environmentally degradable components are used. To solve this problem, gases such as nitrogen gas or carbon dioxide gas are used for the GCP instead of air containing oxygen.

[0221] In the so-called GCP, a method in which a mold is sealed with an O-ring for PL etc., a load-type O-ring for ejector pins etc., or an ejector box, and then pressurized with a gas (usually air) to above atmospheric pressure before filling it with foamable resin, and the gas inside the mold is evacuated during or after filling with the foamable resin to obtain a foam-molded product with a smooth, clean surface and an internal foam layer, if the gas used is air, discoloration and burning will occur, but if the mold is pressurized in advance (this is called "pressurization", also known as "compressed air" or "pressurizing") and the gas used for pressurization is not air {air contains oxygen, so discoloration and burning will occur.} but inert nitrogen gas is used, discoloration and burning can be reduced. First, the inside of the sealed mold is pressurized with air, and then nitrogen gas with a higher pressure than the air is introduced into the cavity, and the initial air is expelled and replaced by the nitrogen gas pressure. In this case, the nitrogen gas is mainly used to pressurize the inside of the cavity, and other parts of the mold, such as the space at the bottom of the insert and the inside of the ejector box, are pressurized with inexpensive air, which is more economical than pressurizing the entire sealed injection mold with nitrogen gas. Sometimes, a vacuum is used to remove the initial air, and then nitrogen gas is used again to pressurize the chamber. It is also possible to use nitrogen gas to pressurize the chamber from the beginning. GCP is explained in PCT / JP2016 / 86380, PCT / JP2015 / 062611, and PCT / JP2020 / 015536, and the contents of the above-mentioned documents are used in the foam molding, GCP, blow molding, and pressure molding of the present invention.

[0222] (Fluid support) Using carbon dioxide gas in the GCP not only prevents discoloration and burning, but also has the effect of improving the fluidity of the molten resin by entering the leading edge of the flow of the molten resin filled in the cavity. Carbon dioxide gas has a higher affinity with molten resin than nitrogen gas, and when nitrogen gas dissolves in it, the fluidity improves. A mixture of nitrogen gas and carbon dioxide gas can also be used.

[0223] Even when a sealed mold is not used, the mold is closed and nitrogen gas with a pressure equal to or greater than atmospheric pressure is introduced into the cavity before filling with molten resin (which can be either foamable or non-foamable resin). The air in the cavity is initially replaced with nitrogen gas, and then the molten resin is filled in the process. In this process, the injection of nitrogen gas can be stopped before the molten resin is filled, or the injection of nitrogen gas can be continued once filling has begun until filling is completed.

[0224] (Flow support and dispersion) A fluidity improver is used to increase the fluidity of molten resin, but in molding equipment, extruders and injection molding machines, a hole is made in the heating barrel, and liquid that vaporizes at the temperature inside the heating barrel, such as water, alcohols, a mixture of water and alcohol, or other organic solvents, is poured in through the hole, and the fluidity of the molten resin can be significantly improved. Naturally, if the fluidity can be increased, the dispersibility of the environmentally degradable components in the thermoplastic resin can also be increased. An anionic, cationic, or nonionic surfactant can be added to this liquid (used in combination). Commercially available dispersants can also be used.

[0225] In addition to the liquids mentioned above, gases such as nitrogen gas and carbon dioxide gas can be added to the molten resin to increase its fluidity. Carbon dioxide gas has a higher affinity (ease of mixing) with molten resin than nitrogen gas, so if a gas is used, carbon dioxide gas is the best. Solid blowing agents, such as hydrogen carbonates represented by sodium bicarbonate, chemical blowing agents such as azo compounds represented by ADCA, and nitrosated compounds represented by DPT, as well as physical blowing agents such as hollow air balloons, have the effect of increasing the fluidity of the molten resin in the heating barrel.

[0226] To increase the binding strength between the environmentally degradable component and the thermoplastic resin, if the thermoplastic resin is PP, an emulsion (solvent-based is also acceptable) containing maleic acid-modified PP, which has a high binding strength with PP resin, is placed in the heating cylinder in the same manner as in the case of the liquid described above to increase the binding strength (binding force) between the environmentally degradable component and the PP resin. If the thermoplastic resin is a styrene-based resin such as ABS, a solution of styrene-modified acrylic resin in emulsion or a solution of styrene-modified acrylic resin dissolved in a solvent is used. If the thermoplastic resin is polyamide, a solution or emulsion of methoxymethylated polyamide can be used in the same manner and placed in the heating cylinder. Of course, maleic acid-modified PP, styrene-modified acrylic resin, methoxymethylated polyamide solid (powder, etc.), and polyvinyl alcohol may be mixed together. In this case, if the maleic acid-modified PP or the like is in a solid state, they are mixed in the tumbler (tumbling) stage and then fed into the extruder hopper, etc.

[0227] Liquefied carbon dioxide gas is injected into the barrel and vaporized at the temperature of the heating tube, and can be used as a flow improver as carbon dioxide gas in the heating tube. Solid carbon dioxide gas (dry ice) is pelletized, and a device with a mechanism like a back melter is installed in an extruder, injection molding machine, or other molding device, and a mixture of dry ice, environmentally degradable components, and thermoplastic resin is placed in the heating tube and melted. When melted, the dry ice sublimes and becomes carbon dioxide gas, which dissolves in the molten resin. As a result, the molten resin in the heating tube has improved flowability because carbon dioxide gas has been dissolved in it. Dry ice can be used as a flow improver. Another method is to improve the fluidity of substances that impart foaming properties to the molten resin in the heating barrel, such as hydrogen carbonates (salts of alkali metals such as Li, Na, and K), azo compounds such as ADCA, and nitrosated compounds such as DPT. Another method is to introduce gases such as MU-CEL, AMOTECH, and SOFIT into the heating barrel to impart foaming properties to the molten resin in the heating barrel, which will improve fluidity. Of course, there are also fluidity improvers as another method.

[0228] (Embodiment 15) (Pellet manufacturing) The particle size of the environmentally degradable component used in the fifteenth embodiment is not particularly important. It may be large or small. In some cases, large and small particles may be mixed together. The average particle size of the cellulose powder (KC Flock W-100GK, W-50GK, W-400G) manufactured by Nippon Paper Industries Co., Ltd. used in the examples of the present invention is sufficient if it is 200 μm or less, and when uniformity (uniform dispersion) is required to be improved in dispersibility, 20 μm or more and less than 50 μm are used. The cellulose powder KC Flock manufactured by Nippon Paper Industries Co., Ltd. is originally a white powder like shoji paper. A mixture (referred to as "Mixture 001" in the present invention) of 51 wt.% of this white powder (cellulose powder) and 49 wt.% of natural colored PP resin {Sumitomo Noblen HX101A (product name)} was heated and melt-kneaded with a kneader {pressure kneader manufactured by Toshin Co., Ltd.} using an electric rod heater for heating. The melting temperature was adjusted to below 200°C, but the product that was melted and kneaded with the cellulose powder and PP resin turned brown (originally, both the cellulose powder and the PP resin pellets were white.) It was speculated that the cause of this was the cellulose powder being oxidized by the air (oxidized by oxygen in the air), causing the discoloration.

[0229] To confirm whether the discoloration was caused by oxygen in the air, the heating section of the kneader was enclosed in a vinyl bag and inert nitrogen gas was poured inside {Nitrogen gas was continuously poured in while melting and kneading in the kneader, replacing the air and sealing the resin melting environment (the atmosphere during melting and kneading) with nitrogen gas. ) Similarly, when it was melted and heated at 200℃, there was almost no discoloration and it was white, compared to the one melted and kneaded in air. This made it clear that the discoloration was caused by oxygen in the air. Although slight discoloration was observed, it was assumed that this was due to air getting into the gaps between the cellulose powder and PP pellets.

[0230] When the melt-kneaded lump of PP resin containing the cellulose powder was taken out of the nitrogen gas atmosphere into the air, the surface temperature was close to 200°C, the same as during melt-kneading, and the surface turned brown due to the oxygen in the air. This experiment confirmed that cellulose powder is easily oxidized and discolored, but this discoloration problem can be solved by replacing the air with an inert gas such as nitrogen gas.

[0231] Conventional resin (e.g. PP resin) pellets are made by cooling strands in water and then cutting them into pellets. However, since the environmentally degradable components have high water absorption, cooling in water is not preferred and air cooling is preferable. The molten mass of PP resin containing cellulose powder that had been melt-kneaded earlier, before it had completely cooled and solidified, was extruded using a plunger-type extruder and cooled in air on a stainless steel mesh conveyor (as cellulose has high water absorption), and strands were extruded and cut using a pelletizer to obtain PP resin pellets containing cellulose powder. However, at the stage of extruding and forming strands using the plunger, the process was carried out in air (strand cutting, air cooling and solidification), so the surface of the strands was oxidized and turned brown.

[0232] It was confirmed that discoloration can be prevented by replacing the air with nitrogen gas, as in the case of the kneader. Specifically, the conveyor is enclosed in a tunnel structure, and nitrogen gas is poured inside to replace the air with nitrogen gas. The strands extruded from the die are cooled by blowing nitrogen gas onto them. In this way, by replacing the air with nitrogen gas at the melt-kneading stage and the stage of pulling the strands and pelletizing them, oxidation of the cellulose powder can be prevented, and white pellets without discoloration can be obtained. Although only cellulose is used in the above embodiment, cellulose powder and paper powder (either from a paper mill or paper collected from the market that has been pulverized) can also be used. These can also be mixed together.

[0233] (Embodiment 16) (Method to prevent oxidation: nitrogen gas sealing) From the third embodiment, it was confirmed that the discoloration of the cellulose powder (due to oxidation) is caused by oxygen in the air. However, the pressurized heated kneader is a batch-type production (manufacturing) method, and therefore the productivity is low. To obtain pellets, continuous production using a single-screw or multi-screw extruder and a pelletizer reduces production costs and is more economical. The 16th embodiment shows a method for obtaining discolored pellets without oxidation using an extruder. Mixture 001 is placed in the hopper of an extruder, and the air in the hopper is replaced with inert nitrogen gas. In practice, nitrogen gas can be continuously introduced into the lower part of the hopper (preferably the part of the pipe connected to the heating cylinder) using a thin hose. Nitrogen gas can be purchased from a commercially available cylinder, but in this case, nitrogen gas cylinders are expensive and not economical. The inventor used nitrogen gas separated from the air using PSA (Pressure Swing Adsorption) or a nitrogen gas separation membrane {hollow fiber (N2 separator) sold by UBE Co., Ltd.}.

[0234] As mentioned above, by replacing the air inside the hopper with nitrogen gas, the oxygen concentration will decrease, and discoloration due to oxidation will be avoided. To prevent further discoloration, for example, a high vacuum plasticizing device inside the heating cylinder {Bacmelter (product name)} manufactured and sold by Meiki Seisakusho Co., Ltd. and Japan Steel Works Co., Ltd. as an attachment to molding machines is used. Mixture 001, whose hopper has been replaced with nitrogen, is placed in the heating cylinder, and before melt-kneading, a vacuum is drawn using the backmelter to suck out the air that has entered the gaps between the cellulose powder and PP resin pellets. The mixture may be placed in the heating cylinder as is and melt-kneaded.

[0235] If necessary, after drawing a vacuum, nitrogen gas can be pumped into the back melter, and the air in the gaps will be replaced with nitrogen gas. To further increase the effect of replacing the nitrogen gas, use multiple back melters instead of one.

[0236] Mixture 001, whose air has been replaced with nitrogen gas, is fed into the extruder for melting and kneading, but in order to stabilize the amount fed into the extruder, small sub-screws (feed screws) are installed above the heating barrel, below the hopper, and between the heating barrel and the hopper. In this case, it is advisable to also replace the air inside the sub-screw with nitrogen gas. This is necessary and recommended to prevent discoloration.

[0237] The extruder may be a single screw (one screw) or a multi-screw (e.g., two-screw) extruder with strong (high) mixing ability. In the case of a multi-screw extruder, the rotation directions of the screws may be either synchronous or counter-rotating. In the case of an extruder, a vent is provided in the heating cylinder. This vent is also covered and nitrogen gas is poured inside to perform nitrogen gas sealing (meaning replacing air with inert nitrogen gas). After melting and kneading, the material is extruded through a die to form strands. It is cooled and solidified using a stainless steel mesh conveyor belt. As explained above when pellets were obtained using a kneader, during the cooling and solidification stage, in order to prevent discoloration due to oxidation on the strand surface, nitrogen gas replacement (replacement of air with inert nitrogen gas; replacement of oxygen in the air with nitrogen gas) is similarly performed to prevent discoloration on the strand surface due to oxidation when it comes out of the die. Once cooling and solidification is complete, the temperature drops and the material is pelletized (cold cut). By thus lowering the oxygen concentration in the air to approximately zero, white pellets can be obtained without discoloring the cellulose powder. By adding pigments and dyes during the pellet manufacturing process, pellets containing cellulosic powder in various colors can be obtained. Furthermore, PP does not oxidize at a melting temperature of 200°C. Therefore, it has been confirmed that PP does not discolor or burn at around 200°C.

[0238] When a dulmage screw is used for the extruder in order to enhance the kneading property, the kneading property is high, and therefore the environmentally degradable component is highly dispersible in the thermoplastic resin. If a vaporizable liquid is introduced into the molten resin in the heating barrel after melt-kneading by the means shown in Patent Publication (PCT / JP2015 / 062611), not for the purpose of foaming as in Patent Publication (PCT / JP2015 / 062611), but rather to lower the melt viscosity of the molten resin in the extruder heating barrel, the kneadability of the cellulose powder and the PP resin is improved, and dispersibility is improved. Since the purpose is not foaming, the amount of ethanol to be added is, for example, 1 part or more, preferably 3 parts or more, per 100 parts of the molten resin containing the environmentally decomposable component. The vaporizable liquid should be alcohols such as ethanol and propanol, water, or a mixture of water and alcohols. Methanol can be used, but is not recommended due to its toxicity. Its use is discontinued in this invention. If you add dyes to this liquid, you can color the pellets. Liquid injection is not limited to one place, but can be done in several places. You can also add a solution containing alcohol, dyes, or pigments. In order to increase the bonding strength between the cellulose powder and the olefin resin PP and to increase the strength of the final molded product, an emulsion-type solution of maleic acid-modified PP (model number DB-4010 (Arrowbase (product name)) sold by Yuichika Co., Ltd.) may be added to increase the bonding strength at the interface / boundary region between the cellulose and PP. Naturally, it is possible to make it even whiter by adding white inorganic substances such as titanium oxide, alumina, and magnesia. Use plasticizers, preservatives, anti-mold agents, dispersants, etc. as necessary. If these substances are solid, mix them in appropriate amounts with Mixture 001, for example. In the case of a solution using an organic solvent such as alcohol, the solution may be injected into the heating cylinder using the liquid injection device described above (Patent Publication PCTPCT / JP2015 / 062611) shown in Figs. 1, 4 to 19.

[0239] (Embodiment 17) (Injection molding processing) The following describes a method for preventing oxidation of cellulose powder when the cellulose powder-containing pellets 001 obtained in the third and fourth embodiments using the mixture 001 are injection molded. The means for this is nitrogen replacement and nitrogen sealing, as in the case of pellet 001, and discoloration and burning during injection molding can be prevented. First, the inside of the hopper of the injection molding machine is replaced with nitrogen gas. The replacement method is the same as the nitrogen replacement method in the hopper when pellet 001 was produced using an extruder in the above pellet production. The inside of the hopper is replaced with nitrogen, and then the pellets are plasticized in the heating cylinder of the injection molding machine. The injection molding machine of the fifth embodiment is equipped with the back melter described above, and the pellets 001 in the hopper have some of the air in the gaps between the pellets replaced with nitrogen gas, and then the pellets are sent into the back melter. The back melter is evacuated, and the pellets are sent into the heating cylinder, where they are melted, plasticized, and kneaded. After the back melter is evacuated, nitrogen gas may be introduced into the back melter again. Naturally, a single-stage back melter is sufficient, but if multiple stages are used in series, the nitrogen gas replacement rate can be further increased. In this way, the gaps between pellets 001 are replaced with nitrogen gas, so discoloration and burning caused by oxygen do not occur during the plasticization and melting / kneading stages.

[0240] The pellets 001 plasticized in the heating barrel of the injection molding machine are then filled into the mold, but since there is air in the cavity of the mold, actually the oxygen in the air, there is a risk of discoloration and burning in the resulting molded product. If the injection speed is increased, discoloration and burning will increase due to adiabatic compression. In order to solve this problem, the inside of the cavity is replaced with an inert gas, for example, nitrogen gas. A specific method for replacing the inside of the cavity with nitrogen gas will be described below. The mold used is provided with gas injection pins and gas pressurization pins shown in Fig. 52, Fig. 53, and Fig. 54 in the patent publication (PCT / JP2016 / 86380) on either the fixed side, the movable side, or the spool runner (multiple are possible). The mold is closed, and the valve (reference number 14) in Fig. 1 of the patent publication (PCT / JP2016 / 86380) is opened to blow nitrogen gas into the cavity. When the air in the cavity is replaced with nitrogen gas, the molten resin of the pellet 001 is injected (filled) into the cavity. When the cooling and solidification of the molten resin is completed, the mold is opened and the molded product is taken out, and a beautiful white injection molded product without discoloration or burning is obtained, which is injection molded using the pellet 001 produced using the mixture 001.

[0241] (Embodiment 18) Pellet 001 contains 51wt% cellulose powder, so its fluidity is significantly lower than that of 100% PP resin. Furthermore, because of concerns about discoloration and burning of the cellulose powder, the resin temperature during molding cannot be made very high. Therefore, as an application of the foam molding method using liquid described in the patent publication (PCT / JP2015 / 062611) as a means to increase the fluidity of the molten resin, alcohols, water, and a mixture of alcohols and water are added to the molten resin in the heating cylinder to improve the fluidity of the molten resin. Since the amount added is not foam molding, an amount several times more than that of foam molding is added, the fluidity is increased, and the resin is injected into a cavity replaced with nitrogen gas, and then the resin is held under pressure to squeeze out the liquid. This is a means of using a foaming agent and holding pressure to prevent foaming. Naturally, there is a risk of discoloration and burning, so the inside of the hopper and cavity are replaced with inert gas and sealed with inert gas.

[0242] We have previously shown the use of alcohol as a liquid to improve the flowability of thermoplastic resin (as a means of injecting it into the heating barrel), but the material is not limited to alcohol. The same flow support effect can also be achieved by using nitrogen gas or carbon dioxide gas pressurized to a level where it can be injected into the molten resin in the heating barrel (pressure higher than the back pressure of the molten resin in the heating barrel during plasticization and melting). In addition to liquids such as alcohols, and gases such as nitrogen gas and carbon dioxide gas, baking soda (sodium hydrogen carbonate, sodium bicarbonate, sodium acid carbonate), ADCA (azo dicarboxylic acid amide), DPT (di-nitroso pentamethylene tetramine), and other medium-sized air balloons such as Advancel (trade name) and Expancel (trade name) can also be expected to have a similar fluidity support effect.

[0243] (Foam molding) Although the action and effect of flow support using a liquid has been explained above, it is of course possible to carry out foam molding using pellets 001. In the sixth embodiment, alcohols are used as a flow improver, but foam molding is possible if the amount added is reduced and an appropriate amount is used, and alcohols are also used as a foaming agent. The cellulose powder in the pellet 001 acts as a foam nucleating agent, and talc, metal oxides, inorganic fillers, etc., which act as nucleating agents for the purpose of foaming, may be added as necessary.

[0244] {Gas Counter Pressure (GCP), mainly outer GCP} Naturally, the Gas Canter Pressure (GCP) method described in the patent publication (PCT / JP2016 / 86380) and the literature {S&T Publishing Co., Ltd. October 20, 2022, 1st Edition, 1st Printing "Preparation for Mass Production of Foam Molding, Blow Molding, and Compressed Air Molding, and Explanation of Specific Means for Reducing Environmental Impact" by Yasutaka Suzuki and Minoru Shinbo} can be used to reduce floating on the surface of cellulose powder. By increasing the GCP pressure (pressurization inside the mold) and increasing the mold temperature, the floating of cellulose powder due to the effect of GCP can be further reduced. In GCPs using general resins such as ABS and PP, the gas used to pre-pressurize the inside of the mold is air, but air can cause problems with discoloration and burning, so inert nitrogen gas is sometimes used instead. When carbon dioxide gas is used, it dissolves into the molten resin from the front of the flow, improving the fluidity of the molten resin and reducing (holding down) the floating of the cellulose powder. Naturally, in the case of this foam molding, as explained in the fourth embodiment (which is extrusion molding, but is roughly the same for injection molding) and the fifth embodiment, it is necessary to carry out nitrogen replacement in the hopper and nitrogen replacement using a device such as a back melter.

[0245] (Embodiment 19) (Extrusion molding = sheet extrusion molding) When using pellets 001 for extrusion molding to produce sheets, the inside of the hopper is sealed with nitrogen and replaced with nitrogen, as in the case of the injection molding, and if a feed screw is provided on the extruder heating barrel, the air in the feed screw is also replaced with nitrogen to prevent discoloration and burning due to oxidation, before putting the pellets into the heating barrel, plasticizing them, and extruding the sheets. This is the same for both injection molding machines and extrusion molding machines, but as long as oxygen does not enter the heating barrel, there is no need to worry about discoloration or burning even if the temperature is raised slightly.

[0246] However, when the sheet comes out of the extruder die, it has not yet cooled and solidified, and is still at a high temperature, so when it comes into contact with air, the surface will naturally oxidize and discolor. In some cases, burning may occur. The sheet must be in a nitrogen gas atmosphere until the surface has cooled and solidified completely, and the surface temperature has dropped to a point where it no longer oxidizes and discolors. Once cooling and solidification is complete, the sheet is cut to the desired size and used for pressure forming or vacuum forming.

[0247] In both the case of the extrusion molding for producing the sheet of the 19th embodiment and the case of the previous 18th embodiment, if a vent is provided in the heating barrel, air may enter the heating barrel through the vent and be oxidized, resulting in discoloration and burning. Therefore, nitrogen gas is introduced through that part (the vent section, vent opening, etc.) to prevent oxidation of the molten resin in the heating barrel. Another port is provided to add the environmentally degradable component in a slurry form (described later) to the heated and melted thermoplastic resin and knead it in. During the heating, melting and kneading stage, the water, organic solvent, etc. used in producing the slurry are sucked in through yet another vent port and released to the outside of the heating cylinder. The slurry is produced by adding water and / or an organic solvent such as alcohol to the environmentally degradable components and using a Henschel mixer, etc. For the produced slurry, in the case of single-screw or multi-screw extrusion molding, if the thermoplastic resin is an olefin resin such as PP, a maleic acid-modified PP solution (including water-based) is used, and if the thermoplastic resin is a styrene-based resin such as ABS or HIPS, a styrene-modified acrylic resin solution (including water-based) is used. When the slurry is melt-kneaded using a single-screw or multi-screw extruder to produce pellets, the slurry is melt-kneaded by continuously injecting a fixed amount of the slurry into the molten resin in the heating cylinder using a plunger pump or the like. In the case of injection molding, a certain amount of slurry is injected into the molten resin in the heating barrel of the injection molding machine from the start to the end of metering. This is called volume control. In the case of injection molding machines, the liquid injection device shown in the figure (photo 17 on page 36) in the literature {S$T Publishing Co., Ltd. October 20, 2022, 1st edition, 1st printing "Preparation for mass production of foam molding, blow molding, and compressed air molding, and explanation of specific measures to reduce environmental impact" by Yasutoshi Suzuki and Minoru Shinbo} can be used. In addition, Figure 32 and photo 24 on page 66 of this book show a gas counter pressure device.

[0248] (Embodiment 20) In the previous embodiment, PP, an olefin resin, was used as the resin (for example, mixture 001, pellet 001), but in the present invention, any resin that exhibits thermoplasticity can be used (is usable). PE can be added to lower the melting temperature of PP, for example, to create a mixed resin (polymer alloy, polymer blend) with PP:PE=50:50. It can also be implemented with only PE (PE alone). Since the PP was in the form of pellets, it was mixed with cellulose powder and pelletized to obtain pellet 001. However, since ABS is commercially available in powder form, the inventor mixed cellulose powder and ABS powder using a tumbler, Henschel mixer, etc. to obtain ABS-containing cellulose powder, and instead of pelletizing it, the powder mixture may be placed in a hopper as is and injection molded as is without pelletizing it. Of course, foam molding using alcohols and GCP are also possible. Other than ABS, ester resins such as PET, vinyl chloride, and polystyrene can also be used. Biodegradable plastics such as polylactic acid can also be used. Polymer alloys and polymer blends of these resins are also acceptable.

[0249] Although alcohol and other liquids have been exemplified as a means of increasing the fluidity of resin, liquefied carbon dioxide gas can also be used. If the back melter shown above is slightly modified and solid carbon dioxide gas (dry ice) is mixed into it and placed in the heating cylinder, the dry ice will sublimate at the temperature of the heating cylinder and become a foaming gas. By increasing the amount added, it can also be used as a fluidity improver or dispersant.

[0250] In the fourteenth to twenty embodiments of the present invention, the means for carrying out the invention are shown using cellulose powder, but the present invention is not limited to cellulose powder. Environmentally degradable components other than the cellulose powder shown in the present invention are also easily oxidized by oxygen and discolored or burned, so when using these substances, sealing with inert nitrogen gas or replacing with nitrogen gas should be performed.

[0251] (Embodiment 21) (Supported by maleic acid-modified PP, etc.) When the bonding strength between PP and an environmentally degradable component such as cellulose powder is low, a substance having a strong bonding strength with PP, such as maleic acid-modified PP or a halogenated polyolefin such as chlorinated PP or chlorinated PE, is used, for example, on the surface of the environmentally degradable component (e.g., cellulose powder, paper powder, etc.).

[0252] The first step of the implementation will be described below. When the environmentally degradable component is in powder form, in order to eliminate the risk of dust explosion, the atmosphere inside a Henschel mixer is replaced with an inert gas such as nitrogen gas beforehand, and the environmentally degradable component is then placed in the mixer, followed by maleic acid-modified PP (whose properties are emulsion type where maleic acid-modified PP is emulsified, or solvent type where a solvent is dissolved), and the like, and then the environmentally degradable component and maleic acid-modified PP are mixed together by stirring. The obtained mass of the environmentally degradable component containing the maleic acid-modified PP, etc. is crushed to a particle size (size) that can be melt-kneaded with PP resin, mixed with PP, and pelletized or formed into sheets.

[0253] In the case of styrene-based resins such as AS, ABS, PS, and HIPS, instead of PP, styrene-modified acrylic resin, acrylic resin, acid-modified acrylic resin, etc. are used in place of maleic acid-modified PP. As mentioned above, these are available in both emulsion and solvent types, so either can be used.

[0254] Poval (polyvinyl alcohol) dissolved in water or solvent can also increase the binding strength between the environmentally degradable component and the binder resin PP, ABS, HIPS, etc. The method of use (implementation) is the same as that of the maleic acid modified PP solution and styrene modified acrylic resin solution shown above.

[0255] A solution of maleic acid-modified PP or styrene-modified acrylic resin is injected into the heating cylinder and mixed with environmentally degradable components, PP, ABS and other binder resins at the melt-kneading stage. The water in the solution (water in the case of an emulsion) and the organic solvent in solvent-based products also act as flow improvers. In this case, other additives such as pigments and dyes can be injected at the same time. To impart flame retardancy to the resin, the flame retardant can be injected as a liquid using a solvent, water, etc.

[0256] When maleic acid modified PP or styrene modified acrylic resin is solid, the environmentally degradable components and binder resin are mixed in a tumbler that has been explosion-proofed (replaced with inert gas, sealed using inert gas), and then pelletized using an extruder, molded into sheets, or placed in the hopper of an injection molding machine for direct injection molding. Naturally, in this case, it is also possible to use alcohol or other fluidity improvers in combination, and these liquids are injected into the molten resin in the heating barrel using a liquid injection device. Low molecular weight PE (WAX), linear fatty acid, polycaprolactone, or copolymer (resin) of polylactic acid and polycaprolactone may be mixed with PP, ABS, etc. In this case, the viscosity of the molten resin is significantly reduced.

[0257] (Embodiment 22) The embodiment 22 shows a specific means for producing pellets using the mixture 001 by using a single-screw extruder. In the case of a single-screw extruder, the kneading performance is inferior to that of a multi-screw (e.g., two-bow) extruder. However, even in a single-screw extruder, the kneading performance can be improved by putting a dulmage into the screw. Also, the kneading performance can be improved by increasing L (screw length) / D (screw diameter). Also, the kneading performance can be improved by making the screw flight double-flighted. It is also possible to improve the kneading performance by lengthening the compression zone.

[0258] (Screw shape) When producing resin pellets consisting of the environmentally degradable component and thermoplastic resin of the present invention, the produced pellets are semi-finished products (raw materials for producing molded products), and the pellets are heated and melted again at the stage of injection molding, extrusion molding, etc., and therefore it is not necessary to use a two-headed extruder with high kneading properties. Since the pellets are heated and melted again at the stage of injection molding, extrusion molding, etc., and are kneaded again, in order to facilitate workability, the pellets are simply pelletized so that the environmentally degradable component, such as cellulose powder, does not float in the air in the workplace, for example. The environmentally degradable component does not need to be uniformly mixed in the pellets, and it is sufficient that the pellet shape is maintained.

[0259] The screw shape of the extruder can be a single screw, and a screw with a simple flight is also sufficient, but if you want to improve the kneading ability even a little, you can use a double flight (with an additional flight between the flights). If high kneadability is required, Dulmage (e.g., mud type) may be used with environmentally decomposable components. If discoloration or burning of thermoplastic resin occurs, the inside of the hopper and / or the inside of the heating cylinder may be sealed with an inert gas such as nitrogen gas or carbon dioxide gas, and the combustion-indicating gas or combustion-supporting gas, such as oxygen, which causes discoloration or burning, may be replaced with the inert gas, as described in the previous embodiment.

[0260] To improve kneading, for example in the case of injection molding, a shut-off nozzle can be used to increase the back pressure during plasticization and metering, which will improve kneading. In this case, using the mechanism of the Dynamelter (product name) made by Meiki Seisakusho Co., Ltd. (a subsidiary of the Japan Steel Works, Ltd.), a manufacturer and distributor of injection molding machines, will improve kneading even further. In the case of extrusion molding, if the discharge volume is reduced and throttled based on the shape of the die, and the back pressure in the heating barrel is increased, pelletization, sheet molding, and profile extrusion molding are fully possible with a single-screw extruder using the sub-flight screw or the screw with a dalmeage, as described above, without necessarily using a multi-screw extruder.

[0261] The inventor, Suzuki Yasuhiro, has filed a separate patent application (application number PCT / JP2015 / 062611) for injection foam molding using alcohol with a low ignition point inside the heating barrel. In this case, even alcohol, which is easily oxidized, does not cause discoloration or burning of the resin at temperatures inside the barrel (for example, about 230°C for ABS molding). No discoloration or burning of the molded product occurs. This is because there is no air (oxygen) in the heated and molten resin inside the heating barrel.

[0262] However, the cellulose powder and paper powder of the present invention are low in density and contain a lot of air (containing about 21% oxygen). In ordinary extrusion molding and injection molding, if the back pressure is increased slightly, the air escapes from the hopper, but this is not the case when environmentally degradable components are included. The air (actually the oxygen in the air) is an environmentally degradable component, and a large amount of air is contained in the gaps. If it is mixed with a thermoplastic resin as it is and plasticized, discoloration and burning will occur. To solve this problem, the air (oxygen) is replaced with an inert gas. To replace, these environmentally degradable components are placed in a vacuum device, vacuumed to expel the air, and then an inert gas, such as nitrogen gas, is introduced and the pressure is set to normal (1 atm, 760 mmHg), and the air inside is replaced with almost all inert gas. This process may be carried out multiple times as necessary. Next, the required thermoplastic resin is added and mixed (for example, using a tumbler, mixer, etc.). At that time, the mixer (vessel) is sealed with an inert gas, such as nitrogen gas, to prevent air from re-entering.

[0263] This material is placed in the hopper of the extruder, and the inside of the hopper is also replaced with an inert gas in advance to prevent discoloration and burning.

[0264] As mentioned above, the air that has entered the environmentally degradable component can be replaced with an inert gas by drawing a vacuum. Alternatively, for example, the air in the wheat flour can be expelled by mixing the environmentally degradable component wheat flour with water to form a slurry. This wheat flour slurry is mixed with the thermoplastic resin to be melt-kneaded in the extruder of the molding machine, placed in a hopper replaced with an inert gas, and kneaded until hot. The water that was added beforehand can be withdrawn from a vent port midway through the extruder (one end is generally suctioned with a vacuum pump). Other than water, alcohols such as ethanol and propanol may be used. Furthermore, a mixture of the above alcohols and water may be used. Instead of wheat flour, environmentally degradable components such as cellulose powder and paper powder may be used, and these may be mixed together.

[0265] In the pelletizing stage, the compression ratio can be increased to improve the kneading inside the extruder heating cylinder, but this also creates problems with discoloration and burning. In this case too, replacement with an inert gas is effective. As mentioned above, providing a screw with a dull burr is a means of improving the kneading performance, but in this case too, the problem of discoloration and burning can be solved by replacing the air with an inert gas.

[0266] (Embodiment 23) Next, a method for enhancing melt mixing using an extruder will be described. When mixing the environmentally degradable component and the thermoplastic resin and melt mixing them in a single-screw or twin-bore extruder, a hole is opened in the heating barrel and a vaporizable substance {a liquid at room temperature (23°C) and normal pressure (1 atm, 760 mmHg, such as water, alcohol, etc.) is introduced into the heating barrel and vaporized at the temperature of the heating barrel and / or the temperature of the molten resin in the heating barrel, and the vaporized steam melts into the molten resin and / or is finely dispersed, lowering the viscosity of the molten resin, thereby enhancing the dispersibility of the environmentally degradable component in the heated and melted thermoplastic resin. If nitrogen gas is added in addition to the vaporizable substance, the viscosity of the molten resin will decrease, and the environmentally degradable component will be uniformly dispersed in the thermoplastic resin. Carbon dioxide gas may be used in addition to nitrogen gas. Liquefied carbon dioxide gas may also be used. These may also be combined.

[0267] A so-called solid foaming agent such as a substance that generates gas by thermal decomposition at the temperature in the heating cylinder, for example, hydrogen carbonate represented by sodium hydrogen carbonate (baking soda, acidic sodium carbonate, NaHCO3), azo compounds represented by ADCA (azo di-carboxylic acid amide), nitrosated compounds represented by DCP (di-nitroso pentamethylenetetramine), or air bubbles such as Advancel (trade name), may be used in the mixture of the environmentally decomposable component and thermoplastic resin. Dry ice (solid carbon dioxide gas) may be added to the mixture of the environmentally decomposable component and thermoplastic resin. Dry ice may be continuously added to the heating cylinder by opening a window in the heating cylinder using a feed screw.

[0268] The molten resin thus made foamable using a gaseous, liquid, or solid foaming agent naturally becomes pellets that are somewhat foamed (with foam cells inside), but since the pellets are remelted and remixed in the next stage of processing, such as extrusion molding or injection molding, the environmentally degradable components do not need to be uniformly dispersed in the initial pellets. The presence of foam cells inside the pellets does not pose any significant problem.

[0269] There is also a method of using liquefied carbon dioxide gas instead of alcohol. Specifically, if liquefied carbon dioxide gas is added to the molten resin in the heating cylinder, the molten resin is given foaming properties, which results in a decrease in the viscosity of the molten resin and improved kneading properties. If solid carbon dioxide gas (dry ice) is added instead of liquefied carbon dioxide gas, the dry ice will sublimate in the heating cylinder and become gaseous carbon dioxide gas, which will give the molten resin in the heating cylinder foaming properties and similarly improve kneading properties.

[0270] (Embodiment 24) (Method of producing pellets by support) Although the means for pelletizing the environmentally degradable component using a single-screw or multi-screw extruder has been described, it is not necessary to melt-knead the environmentally degradable component and the thermoplastic resin to form pellets. The environmentally degradable component may be supported on the surface of the thermoplastic resin pellets. The term "support" refers to coating the surface of another substance (in this invention, as thermoplastic resin pellets) with some kind of binder or adhesive component. The adhesive component is preferably a resin that is compatible (soluble) with the thermoplastic resin. For example, in the case of PP, an olefin resin, examples include halogenated polyolefins such as chlorinated PP and chlorinated PE, maleic acid-modified PP, and polyvinyl alcohol. In the case of styrene resins such as ABS, for example, AS or doped cement in which ABS is dissolved using n-butanone {methyl ethyl ketone (MEK)}, ethyl acetate, etc. can be used. In the case of HIPS, PS or doped cement produced in the same manner as HIPS can be used. Styrene-modified acrylic resin is compatible with both ABS and HIPS, so styrene-modified acrylic resin varnish, which is the raw material for paints, can be used as a coating agent to support both solvent-based and water-based (emulsion-based) products. For polyamide resins such as 6-Nylon (trade name) and 6,6-Nylon (trade name), methoxymethylated polyamide varnish can be used.

[0271] The supported material does not naturally contain the environmentally degradable components inside the pellets, unlike pellets produced using single-screw or multi-screw extruders, kneaders, pressure kneaders, Banbury mixers, etc., but only on the surface, but as described above, it will be remelted during injection molding or extrusion molding (sheet molding), so it is sufficient to disperse it as uniformly as possible at this stage. For example, in injection molding machines, instead of the conventional single-flight screw, double-flight screws, screws with long compression zones and high compression ratios, or screws with high kneading properties are required to perform foam molding such as mu-cell, so the screws of the injection molding machines are also made to have dulmage. Furthermore, after dulmage, a structure is incorporated in which the flights of the screw are raised in order to reduce the pressure of the molten resin once.

[0272] In the case of sheet molding using an extruder, a multi-screw extruder can be used to obtain high mixing performance, but in the case of a single screw, a screw with high mixing performance can be used by providing a dulmage as described above.

[0273] If a high-mixing screw is used as described above, if discoloration or burning of the environmentally degradable substances and / or thermoplastic resin occurs, the inside of the hopper, etc. can be replaced with an inert gas as described above.

[0274] In addition to the environmentally decomposable component, thermoplastic resin, and coating agent, pigments such as titanium oxide, dyes, etc. may also be added by the above-mentioned supporting means.

[0275] This method of support is also suitable for the production of materials for powder metallurgy. Metal powder is supported on the surface of thermoplastic resin pellets to form pellets for injection molding, which are then injection molded to create a shape (modeling), and sintered in an inert gas, such as nitrogen gas, atmosphere. If alumina, magnesia, zirconia, etc. are used instead of metal powder, it can also be used as a material for manufacturing ceramics (fine ceramics). As with powder metallurgy, ceramic powder is supported on the surface of thermoplastic resin, and molded (shaped) by injection molding, etc., and then fired in a nitrogen gas atmosphere.

[0276] The pellets carrying the thermoplastic resin on the surface are immersed in a liquid, such as a solution containing a dispersant, before molding, and then dried as necessary, and then extrusion molding, injection molding, or the like can be carried out.

[0277] (Embodiment 25) (Volume reduction) Environmentally degradable ingredients such as cellulose powder, paper powder, and bran are in the form of powder, and because they have low density and are bulky, they do not easily enter the heating cylinder even if they are put directly into the hopper of the extruder. To solve this problem, a small amount of water or a solvent such as alcohol is added to the cellulose powder to make it into a slurry, which is then pressed to reduce the volume and increase the density, and then mixed with PP pellets and melt-kneaded. When an extruder is used, the environmentally degradable component in a slurried form is fed not through a hopper but through a separate port provided in the heating barrel, and mixed and kneaded with the molten resin in the heating barrel. In the case of an injection molding machine, it may be fed through a separate port provided in the heating barrel, as in the case of the extruder. In these cases, the volume (amount added) of the component is controlled relative to the molten resin.

[0278] (Embodiment 26) (Sheet molding) When forming a sheet using the pellets of the resin containing the environmentally degradable component of the present invention, an extruder is used. In this case, the extruder may be a single-screw extruder, but using a multi-screw extruder, for example, with the same or different rotation directions, allows the environmentally degradable component to be uniformly and finely dispersed in the thermoplastic resin. In this case, if there is a concern about discoloration or burning, the air can be replaced with an inert gas as described above, for example, by replacing the air in the hopper with nitrogen. In order to reduce the viscosity of the molten resin, adding a liquid to the molten resin in the heating cylinder will improve the flowability and kneadability. If a multi-screw extruder is used to mold a sheet, the environmentally degradable components in the pellets do not need to be uniformly or finely dispersed. A single-screw extruder can be used to pelletize the pellets. In this case, if the screw of the single-screw extruder is double-flighted or equipped with a dulmage or similar, pellets containing the environmentally degradable components can be produced sufficiently even with a single-screw extruder. If it is desired to further increase the content of the environmentally degradable component, for example, pellets containing about 30 wt.% of the environmentally degradable component can first be prepared using a single screw, and then the pellets (containing 30 wt.% of the environmentally degradable component) can be supported by using a varnish such as maleic acid-modified PP, styrene-modified acrylic resin, or poval to support, for example, 30 wt.% of the environmentally degradable component. This will allow the production of pellets for use in sheet molding or injection molding that contain 30 wt.% of the environmentally degradable component in the pellets and support 30 wt.% on the surface.

[0279] (Embodiment 27) In Fig. 44, an environmentally degradable component is mixed into the molten resin in the heating cylinder, and the mixture is melted and kneaded to produce a resin raw material, mainly composed of thermoplastic resin containing the environmentally degradable component, such as resin pellets for injection molding, and sheets for vacuum molding and compressed air molding. In Fig. 45, reference numeral 185 denotes a hopper for putting in the environmentally degradable component, such as pulp powder and oil powder. Reference numeral 186 denotes a hopper for putting in the thermoplastic resin with which the environmentally degradable component is melted and kneaded. When the sub-screws 197 and 198 rotate, a certain amount of the environmentally degradable component enters the heating cylinder 192 of the extruder. When the sub-screw 198 rotates, a certain amount of the environmentally degradable component enters the heating cylinder 192 of the extruder. The environmentally degradable component in 185 and the thermoplastic resin in 186 (in the form of pellets, powder, crushed bulk, etc.) enter 192, where they are mixed by the rotation of the screw in 193, and heated by a heater (not shown) provided in 192. The thermoplastic resin melts, so that the environmentally degradable component enters the molten thermoplastic resin, is dispersed by the force of the rotation of the screw 193, and is pushed forward. The arrow in 189 indicates that the environmentally degradable component is pushed out by the rotation of the sub-screw 198. The arrow in 196 indicates that the thermoplastic resin in 192 moves forward by the rotation of the screw in 193. The amount of each of them put into the heating cylinder can be adjusted by the rotation speed of the respective screws 196 and 197, and the content of the environmentally degradable component in the thermoplastic resin is determined by this rotation speed. This is called a weight control device, weight control feeder, weight feeder, etc.

[0280] (Embodiment 28) Figure 46 shows an apparatus for introducing an environmentally degradable component into a previously melted resin, the apparatus being composed of the hopper 185 and reference number 198 of Figure 45. Compared to Figure 45, it is separated from the hopper reference number 186. In Figures 45 and 46, reference numeral 194 denotes a vent. Reference numerals 187 and 188 denote the introduction of inert gas into the hopper in order to prevent discoloration and burning of the environmentally decomposable components. Reference number 195 is the die of the extruder, from which the strand comes out, and by hot cutting (not shown), pellets containing environmentally degradable components can be produced. However, even in this case, it is necessary to prevent discoloration and burning due to inert gas. Instead of hot cutting, it is also possible to cut after air cooling. In this case too, the material is cooled and solidified in an inert gas atmosphere such as nitrogen gas, and then cut into pellets. In the case of sheets, they are extruded from a die in the same way as pellets, and then cooled in air, or if necessary, in an inert gas, to prevent discoloration and burning.

[0281] The environmentally degradable component to be put in the container 185 may be used as it is in powder form. It may also be used after being moistened with water, alcohol, etc., or it may be made into a slurry by adding a large amount of liquid. The container 198 may be filled with gas and / or liquid to lower the melt viscosity of the resin, making it easier for the environmentally degradable component to disperse in the thermoplastic resin. The device using small screws (subscrews, feed screws) as shown in Figures 45 and 46, numbered 197 and 198, to feed a stable amount into the heating barrel of the molding machine, is similar in structure and function to the Dynamelter (product name) manufactured by Meiki Seisakusho Co., Ltd. The FCM device (Farrell type continuous mixer) manufactured by Nishida Giken Co., Ltd. may also be used.

[0282] To reiterate, "environmentally degradable components" refer to substances that are decomposed in nature by organisms such as earthworms and microorganisms such as bacteria. Materials that can be photodecomposed, thermally decomposed, or hydrolyzed are also included in environmentally degradable components. In addition, the thermoplastic resin that is the main component can be any resin that exhibits thermoplasticity in the present invention, such as styrene resins such as PS, HIPA, and ABS, olefin resins such as PE and PP, ester resins such as PET, polyamide, and vinyl chloride. In the present invention, the term "main component" refers to a component that is contained in the resin at a content of 10% or more by weight or volume. The terms "main component" and "constitute" are roughly synonymous, and for example, "the thermoplastic resin that constitutes the pellets" means that the pellets contain 10% or more of the thermoplastic resin.

[0283] (Embodiment 29) (Final Processing) Another issue is how to dispose of molded products made from composite materials whose main component is a thermoplastic resin containing environmentally degradable components. The final disposal of molded products containing environmentally degradable components is to either landfill them or incinerate them to recover the thermal energy. If landfilling is to be carried out, it is important to check whether they contain any harmful substances, and if incinerating them, whether they emit gases that pollute the air, whether the combustion gases will pollute the air, and whether the combustion residue (ash) contains any harmful substances. If landfilling is to be carried out, it is important to check whether they contain any harmful substances. However, current molded products only have a recycle mark indicating the main component of the product, which raises concerns about environmental pollution, and therefore neither incineration nor landfilling is possible.

[0284] {Upper regeneration, equal regeneration, lower regeneration (lower regeneration)} For example, to recycle molded products, EPS (expanded polystyrene) used in fish boxes is heated and melted to return it to GP (PS), and then the fish boxes are used again. Recycling from the same thing to the same thing, to something of the same value, is called "equivalent recycling". By adding about 20 wt.% of graft rubber, which is butadiene rubber containing butadiene rubber copolymerized with styrene, to the PS obtained by reducing the volume of the fish boxes, it is possible to make PS {HIPS (high impact polystyrene)} with high attack properties. This can be used to manufacture HIPS from fish boxes, for example, for molded products such as home appliances and office equipment. Recycles that increase the value of resin in this way are called "upper recycling". On the other hand, recycling that recovers heat energy by burning molded products, or recycling into imitation wood, is called "lower recycling". In any of the above mentioned recycling processes, it is important to ensure that the molded articles to be disposed of do not contain any harmful substances.

[0285] However, it takes a lot of time and effort to analyze each molded product to be recycled using analytical equipment such as GC-MASS, FT-IR, and fluorescent X-ray analysis before recycling it. In reality, it is impossible. The inventor has made it possible to easily grasp the type and amount of all materials that make up a molded product, such as the weight of the molded product for molded products weighing 100 grams or more, the type and amount of the resin of the molded product, the number average molecular weight of the resin, the molecular weight distribution, the type and amount of flame retardant and flame retardant auxiliary, the type and amount of pigment and dye, and if a coating is applied, the type and amount of the resin for the coating film that is the main component of the coating film (e.g., urethane-based, one-liquid lacquer-based, etc.), the type and amount of pigment and dye in the coating film, and other additives, just by looking at the molded product. The inventor has made it possible to easily, reliably, and instantly read the information required to recycle molded products by using barcodes, two-dimensional barcodes, QR codes, alphabets, and combinations of alphabets and numbers on the molded products. Specifically, in the case of injection molded products, for example, a symbol consisting of numbers and letters, a barcode, a QR code (two-dimensional barcode), etc. are engraved on the mold. This barcode, etc., contains the type and amount of additives to the resin that composes the molded product mentioned above, the molecular weight distribution of the resin, the number average molecular weight, the graft ratio in the case of graft copolymerization, the type of grafted monomer, and, in the case of flame retardant products, the type and amount of flame retardant and flame retardant assistant, the weight of the molded product, etc. At the recycling stage, the barcodes are read and the data is entered into a computer, after which the material is crushed. The crushed material contains the necessary information for regeneration (recycling), so it is possible to manufacture new resin using recycled materials by adding a certain amount of resin and resin additives to the crushed material. In this way, by collecting molded products from the market, the weight of the molded products, the type and amount of resin contained in the molded products, and the type and amount of additives contained therein can be accurately determined, making it easy and reliable to recycle and improve and modify the resin using recycled materials.

[0286] The type of resin mentioned above, for example the ratio of An (acrylonitrile) to styrene (An ratio) in AS resin, the type and amount of rubber, size distribution, and the type and amount of additives if graft rubber is added, are secrets of the manufacturer that produces and sells the molding material and are not easily disclosed. Since the resin used for recycling is not limited to only one company, this information must be encrypted using prime numbers, etc., and measures must be taken to ensure that it is never leaked to outsiders. To produce new resin using recycled materials, AI is used to determine the new resin blend desired by the AI. Naturally, the physical and chemical properties of this new resin calculated by the AI ​​are confirmed by actually molding test pieces such as dumbbells to check whether they meet the required values. Figure 44 (photo) is a QR code 206 that was engraved (actually engraved on the mold) on an actual molded product to be recycled. When this QR code was scanned with an iPhone camera, the URL (homepage) of Ryumai Plastic Co., Ltd. (535 Ryumai-cho, Ota-shi, Gunma Prefecture), the manufacturer of this molded product, appeared, and it was confirmed that the QR code engraved on the molded product can actually be read. A detailed explanation of this embodiment 29 is given in the literature {S&T Publishing Co., Ltd., October 20, 2022, 1st edition, 1st printing, "Preparation for mass production of foam molding, blow molding, and compressed air molding, and explanation of specific measures for reducing environmental impact" Suzuki This is stated in the book by Yasukuni Niho Minoru.

[0287] (Embodiment 30) {Means for sealing the ejecting shaft (ejector pin, tilt core, etc.) when using high pressure gas} (Back-up Ring) The known document PCT / JP2016 / 86380 describes a means of sealing a mold using a load-type O-ring (Figures 3, 27, 28, etc. in the above document), but when using a high-pressure gas, such as a gas with a pressure of 35 MPa or 50 MPa (compressed), a load-type O-ring with a spring and a rubber O-ring built in, or a general concave ring, cannot completely seal the mold. Therefore, the inventor uses a resin back-up ring (reference number 200) made of, for example, PEEK (polyether ether ketone) at the bottom of the load-type O-ring 201 as shown in Figure 47. This is particularly effective in the case of an inclined core (Figures 17, 18, 20, 23, 25, 26). A detailed explanation of the load-type O-ring is provided in the literature {S&T Publishing Co., Ltd., 1st edition, 1st printing, October 20, 2022, "Preparation for mass production of foam molding, blow molding, and compressed air molding, and explanation of specific measures to reduce environmental impact," by Yasukuni Suzuki and Minoru Niibo}. There are various means for producing high-pressure gas, such as DC motors, AC motors, servo motors, hydraulic pumps, Power Mameister (product name), and air cylinders (such as Haskell's Gas Booster in the United States). When using a servo motor, the equipment is simple, energy saving, and easy maintenance are advantageous. However, we will explain the case of Haskell's Gas Booster with a compression ratio of 30 / 75 as an example. When the central air cylinder of Haskell's Bus Booster is a servo motor, it is preferable that the servo motor is stopped not halfway, but when the first stage cylinder is at the rear end, or when the two-stage compression cylinder reaches the rear end. In this case, the servo motor will stay at the stopped position due to the pressure of the high-pressure gas in one of the cylinders. If necessary, the servo motor may be mechanically locked (like the mechanical lock of an injection molding machine).

[0288] (Embodiment 31) Using the sealed molds in Figures 19 and 20, GCP was performed using air at a pressure of 1.0 MPa. Foam molding was performed using ABS as the resin and water as the foaming agent. When plating the molded product with nickel (Ni) and then chromium (Cr) on the nickel plating, water is a good foaming agent to use. Foam molded products using ethanol have high adhesion to the nickel plating, and no microcracks occur. When ethanol is used as the foaming agent, many cracks are observed in the nickel plating.

[0289] (Embodiment 32) In Example 31, as shown in Figures 50 and 51, the molding material is fed from a hopper 207 to a screw 210 in a heating barrel 209 stably by shifting (eccentrically) the feed port 208 of the molding material from the center position of the screw 210 so that the molding material is fed into the heating barrel of a molding machine (which may be an injection molding machine, an extrusion molding machine, or other molding machines) and plasticized stably. A gap indicated by 215 is provided between the screw 210 and the heating barrel 207. By providing this gap, it is possible to easily plasticize a composite material that contains a large amount of metal powder or ceramic powder, is kneaded, and is pelletized. In addition, the temperature of the cylinder of the heating barrel is lowered in Figure 51 than in the case of a conventional hopper such as Figure 50, so that discoloration and burning of the material can be reduced when plasticizing a material that is difficult to plasticize and contains environmentally decomposable components.

[0290] In the method of supplying materials to the heater barrel with good bite as shown in Figure 51, simply mix the resin, pellets, and environmentally degradable components to be melt-mixed such as metal powder, ceramic powder, cellulose powder, and paper powder in a tumbler or the like, and then place the mixture in hopper 207 having the structure of Figure 51.Since the materials will easily mix inside the molding machine heater barrel, there is no need to produce pellets containing these materials.

[0291] (Embodiment 33) (Production of molding materials using supporting means) This paper describes a method for manufacturing molding materials for MIM (short for metal (metal powder, metallic) powder injection molding), CIM (short for ceramic powder injection molding), and PIM (short for powder injection molding made of a mixture of metal and ceramic) using the support method explained in this invention. The means for producing molding materials made of thermoplastic resin and containing metal or ceramic powder (in this invention, metal powder is abbreviated as "MP" and ceramic powder as "CP") is, for example, to melt the resin in advance in a heated kneader, and then add the intended amount of MP and / or CP to the molten resin and knead and mix it, and then the mixed resin kneaded with MP and CP is fed into a plunger, single-screw or multi-screw extruder to extrude strands, and then hot-cut, or the air-cooled or water-cooled strands are cold-cut to produce molding materials (in the form of pellets) for MIM and CIM.

[0292] The produced molding material for MIM, CIM, and PIM is injection molded using, for example, an injection molding machine to form a shape. In this case, the molding material for MIM and CIM contains a large amount of MP and CP, so the fluidity in the molten state is significantly reduced. To solve this problem, the inventor used a foam molding method in which a liquid acts as a foaming agent, as described in the document; International Application No. PCT / 2015 / 062611. The fluidity of the molten resin is improved by adding alcohol, water, etc. to the molten resin. To improve the fluidity of the molten resin, the temperature of the resin can be increased separately. The inventor can increase the temperature of the resin (by increasing the heater setting temperature of the injection molding machine heating barrel). In this case, in order to prevent oxidation of the resin in MIM or CIM, or the liquid foaming agent to be put into the heating barrel, nitrogen gas is continuously put into the hopper (or only during plasticization metering) to replace the air, and oxygen in the air enters the heating barrel, preventing oxidation of the resin or the liquid foaming agent.

[0293] The molded products made from MIM, CIM, and PIM molding materials that have been shaped using an injection molding machine are degreased (de-resined) in argon gas and sintered in a nitrogen gas atmosphere to obtain the desired MIM, CIM, and PIM molded products that are primarily composed of MP and CP. After sintering, the MIM, CIM, and PIM molded products are machined as necessary by drilling and cutting to create the final product.

[0294] The above-mentioned MIM, CIM, and PIM manufacturing methods were explained by kneading into molten resin, but they can also be manufactured by the supporting method described in International Application No. PCT / 2020 / 015536. For example, a rocking mixer is used to insert a polymer alloy of PE and PP (referred to as "PE-PP pellets" in this invention) obtained by melt-kneading low molecular weight PE (polyethylene) and PP (polypropylene) in advance, and a required amount of MP or / and CP is added inside. A solution of maleic acid-modified PP is sprayed from the nozzle inside, and MP or / and CP is supported on the surface of the PE-PP pellets. The pellets thus obtained with MP or / and MP supported are shaped using an injection molding machine as shown above, and as described above, they are degreased, baked in a nitrogen gas atmosphere, and machined as necessary.

[0295] When using the above-mentioned support method to manufacture molding materials for MIM, CIM, and PIM, the paste component for supporting MP and CP on the surface of the resin pellets is, for example, in the case of PE-PP pellets, a solution of maleic acid-modified PP, which has a high bond with PP, is good, but a solution mainly composed of ethylene maleic anhydride copolymer is also fine. A solution using poval is also fine, and compatibility (solubility) with PE-PP is not that important, since organic substances such as PE, PP, and maleic acid-modified PP become water and carbon dioxide gas at the final baking stage, and any material will do as long as the MP and CP are attached to the surface of the pellets and injection molding is easy. One possible method is to make MP or CP powder into a slurry or paper mache using, for example, glycerin, and then put the slurry into an extruder or injection molding machine. Through a liquid inlet in the heating barrel, a solution of maleic acid-modified PP, a poval solution, or a solution of straight-chain fatty acid is poured in to produce pellets, or direct injection molding can be performed.

[0296] Specific examples of MP used in the present invention include Zn (zinc), Sn (tin), Ni (nickel), Co (cobalt), Fe (iron), and W (tungsten). Examples of CP include metal oxides such as magnesia (MgO), alumina (Al2O3), zirconium oxide, and spinel (MgO·Al2O3), nonmetal oxides such as SiO2, metal nitrides such as TiN and CrN, nonmetal nitrides such as BN3, and metal and nonmetal carbides such as WC and SiC. These CPs may be used alone or in combination. It is expected that the melting point of CP will be lowered by combining them. Of course, CP and MP may be mixed together.

[0297] Examples of resins that can be used as pellets include the PE, PP, and POM mentioned above.

[0298] To obtain resin pellets for MIM, CIM, and PIM molding, the resin pellets mentioned above are mixed with MP and CP, and a small amount of a flow improver such as straight-chain fatty acid is added to make the subsequent pellet manufacturing and molding easier.

[0299] Of course, when injection molding is performed using pellets for MIM, CIM, or PIM molding obtained by the supporting means, the liquid mentioned above is placed in the heating barrel to increase the fluidity of the molten resin, and the molten resin containing the liquid with increased fluidity (the liquid vaporizes inside the heating barrel because of the high temperature) is filled (injected) into the mold, and if necessary, a holding pressure is applied from the injection molding machine nozzle to increase the internal density. The best position for injecting (putting in) the liquid, that is, the place where a hole is drilled in the heater barrel of the injection molding machine (or extrusion molding machine) and the liquid is injected there, is a position where the molten resin is wrapped around the screw, the liquid is injected, the temperature of the heater barrel and the temperature of the molten resin are used to vaporize it, and the vaporized steam does not escape from the hopper (the inventor prefers the start of the compression zone or within the compression zone). This is a big difference from the conventional technology of injecting gas into the MU-CELL to form a foam. Of course, it is also possible to insert a check valve (check ring) at the rear of the screw, as is used in the MU-CELL. In this case, a hole can be drilled further back (closer to the hopper) to inject the liquid. In the case of MIM and CIM, a dalmage is provided in front of the liquid injection point (as viewed from the direction of the nozzle) to allow the liquid vapor to be more finely dispersed, thereby allowing the MP and CP to be dispersed evenly.

[0300] The inventor has made the hopper inlet eccentric as shown in Figure 51 in order to make it easier for MIM and CIM pellets to be fed into the hopper. This method shown in Figure 51 is effective not only for the above-mentioned MIM, CIM and PIM pellets, but also for pellets containing environmentally degradable components, composite materials containing glass fibers and glass beads, plastic materials and simply for molding pellets of thermoplastic resin. It is an effective method not only for injection molding but also for extrusion molding.

[0301] Furthermore, if a dalmage is provided after the liquid is injected (in the direction of the nozzle), the liquid vapor will be finer and finely dispersed in the resin, and in the case of foam molding using liquid, a foam molded product with finer foam cells can be obtained. The number of liquid injection ports may be multiple, not just one, and multiple Dulmages may be used. Not only liquids, but also combinations of gas and liquid, liquid and solid chemical foaming agents, and foaming agents such as hollow air balloons may be used.

[0302] This embodiment 33 was created by inventor Yasuhiro Suzuki in response to a request from Mr. Makoto Onishi, president of Atect Co., Ltd., and Mr. Yoshitaka Fukushima to include it in the patent specification (for the purpose of preventing future claims or patent applications by competitors, etc.), and was described as embodiment 33. Note that in creating this embodiment 32, information on necessary technology, etc. was provided by the aforementioned Mr. Makoto Onishi and Mr. Yoshitaka Fukushima of Atect Co., Ltd.

[0303] (Embodiment 34) In the above embodiment 33, the screw's high mixing dalmage was described, but if the dalmage is provided before the liquid is injected (for example, at the beginning of the compression zone) (before the screw, on the nozzle side), the liquid dispersibility will be higher, resulting in higher fluidity of the molten resin. In this case, the screw's L (length) / D (diameter) is preferably 18 or more, and if it is 20 or more, swirl marks on the surface can be reduced or eliminated when foam molding is performed using a liquid such as ethanol, isopropanol, water, or a mixture of alcohol and water (which in this case becomes an azeotropic mixture, but this is not so important in foam molding using liquids).

[0304] In fact, the inventor confirmed that no swirl marks were generated on the surface of the foamed molded product when he used homogeneous PP and added 1.5 vol.% ethanol to foam mold it using an injection molding machine with a clamping force of 180 tons (a Dulmage is installed in the screw to disperse gas) installed at the Akashi headquarters of Toyo Machinery & Metals Co., Ltd. Similarly, almost no swirl marks were generated on the surface of the foamed molded product when a mixed solution of ethanol:water was used with a ratio of 6:4.

[0305] (Embodiment 35) As shown in the previous embodiment 34, in the injection foam molding process using a molding machine with a screw having a dulmage, for example, an injection molding machine, it was confirmed that even if a GCP is not used, there is almost no occurrence of swirl marks in the appearance of the foam molding when, for example, the resin is an olefin resin (homo PP resin) and the liquid foaming agent is an alcohol such as ethanol or IPA, or a mixed solution of the alcohol and water {for example, alcohol (ethanol, IPA, etc.):water = 8:2, 7:3, 6:4, 2:8, etc.}. In addition to the screw with a dulmage, the same action and effect as in the case of a dulmage can be expected with a screw with strong kneading properties such as a double flight. In this way, in the case of liquids, for example when foam molding a combination of olefin resin (homo PP, block PP, etc.) and alcohol, it is possible to expect to obtain injection foam molded products with no or few swirl marks even without a GCP, or even if the GCP (pressurization inside the mold, compressed air) pressure is as low as 0.6 MPa or 0.8 MPa, the same as factory air. In the case of GCP using carbon dioxide gas, the carbon dioxide gas dissolves from the leading edge of the flow, increasing the fluidity of the molten resin.

[0306] When using a resin that has been given foaming properties by adding 0.3% (0.3% x 17MPa = 5.1% for NPT) of nitrogen gas with a pressure of 17MPa to the volume of the resin in the heating cylinder, unlike the above liquid, swirl marks on the surface could not be eliminated even with air at a pressure of 1MPa. This is because the amount of gas injected as a foaming agent is too large, and swirl marks cannot be eliminated with a GCP pressure of about 1MPa. Swirl marks can be eliminated by increasing the pressure to a higher pressure, for example, about 5MPa. From these results, in order to obtain beautiful and smooth foam molding products without swirl marks on the surface, liquid foaming agents such as alcohol and water, or solid foaming agents such as baking soda and ADCA are good.

[0307] In addition, with a general screw shape (screws used in normal molding), there is no check valve structure at the rear of the screw (near the hopper), so if gas is used as a foaming agent, the gas escapes to the hopper side, making it difficult to impart foaming properties to the molten resin inside the heating barrel. However, in the case of liquid or solid foaming agents, a screw of a general shape (without a mechanism such as a check valve at the rear) is sufficient. In the case of liquids, the injection port is located at the beginning of the compression zone of the screw (resin), and at this point the resin is melted and wrapped around the screw, so this wrapped resin plays the role of a check. Of course, if a check ring is used, the liquid injection port can be located near the hopper.

[0308] When using liquid to mold plastic magnets, ferrite is bound {Since ferrite alone cannot be molded, thermoplastic resin (any type of thermoplastic resin is acceptable, but currently EVA, nylon 6, etc. are the mainstream) is used.} When molding, whether injection molding or extrusion molding, using liquid improves the fluidity of the molten resin, which results in a higher orientation rate of the ferrite when molded in a magnetic field, and a higher magnetic force. In this case, the size of the ferrite used can be the same, but ferrites of different sizes can also be mixed and used. In this case, sufficient resin holding pressure is used, as described below in the non-foaming foam molding method, such as the previously mentioned PIM.

[0309] (Embodiment 36) In the thirty-sixth embodiment, in the case of foam molding methods using gases currently available on the market, such as MU-CELL, AMOTECH, and SOFIT, the gas to be put into the heating barrel is a gas with a controlled (constant) pressure, but when gas is put into the heating barrel, the pressure inside the tank (actually, the capacity of the accumulator tank of the MU-CELL machine is small. Considering putting gas into the heating barrel at a stable pressure, the capacity of the accumulator tank is required to be equal to or greater than the weight and volume of the molded product) drops, and although gas can be put in at the initial high pressure, the amount that can be put in decreases when the pressure drops. Also, the molten resin in the heating barrel is subjected to various disturbances (variations in the resin's fluidity, differences in water content, variations in the operation of the molding machine during plasticization metering, etc.), and there is variation in the amount of gas (nitrogen gas, carbon dioxide gas, rare gas, etc., which are used alone or as a mixed gas) that gives foamability to the molten resin that enters the heating barrel that enters the heating barrel (due to the problem of the capacity of the accumulator tank mentioned above), which results in variations in the strength of the foaming force. The inventors determined that this is an issue with the currently available MU-CELL machines. In addition, when foam molding is performed by putting gas into the heating cylinder, the gas put into the heating cylinder is all pressure controlled due to the structure of the gas device. This is the issue and drawback of foam molding using the pressure control method.

[0310] In order to solve the drawback (pressure control) of the gas foam molding using this pressure control, the inventor also proposes the use of a volume control type gas injection device shown in Figure 52 in the present invention. Nitrogen gas obtained from a nitrogen gas cylinder, a nitrogen gas separation membrane, PSA, etc. is pressurized to a certain pressure, for example, about 3 MPa, and is introduced from reference number 227 (inlet) through piping 232, 233 into a space 228 defined by a cylinder 220 and a piston 219 or a piston 218. In the case of an injection molding machine, upon receiving a metering start signal, if necessary, after a time-up of an arbitrarily set delay time, the motor 222 rotates, the pistons 219, 218 move forward, and nitrogen gas is injected into the heating barrel of the molding machine in 228. By injecting the nitrogen gas, the nitrogen gas in the heating barrel is finely dispersed in the molten resin by the force of plasticization metering (rotation of the screw), or is pressurized and dissolved. Injection is stopped when a predetermined injection time has elapsed (; timer time-up). Or, it is stopped when metering is completed. By using multiple gas injection devices such as those shown in Figure 52, it is possible to use a gas mixture such as nitrogen gas, carbon dioxide gas, etc.

[0311] When the injection of gas (e.g., nitrogen gas) into the heating cylinder is completed, the motor 222 reverses (reverses rotation) and the piston 218 retreats, for example, to 219, so that the gas to be next injected into the heating cylinder is charged into 228, preparing for the next gas injection into the heating cylinder. Reference number 221 is a rod rod connecting 218 and 219, and this rod portion is machined with, for example, a screw (not shown), and 2218 and 119 move back and forth by the forward rotation (forward rotation) and reverse rotation (reverse rotation) of 222, and gas is injected into the heating cylinder or gas is sucked into 228.

[0312] The device in Figure 52 is not limited to nitrogen gas, and can also be used with gaseous carbon dioxide. However, since the critical temperature of carbon dioxide is 31.2°C, carbon dioxide will liquefy when pressurized in a normal NPT working environment. In this case, carbon dioxide easily goes into a supercritical state, so the sealing material must be made of NBR (nitrile rubber) or similar. When using carbon dioxide as a gas, the critical temperature and critical pressure must be taken into consideration.

[0313] In the case of liquids, since they are incompressible substances, the volume is not affected by temperature as much, but in the case of gases, since they are compressible substances, the volume depends on Boyle's law {pressure (P) x volume (V) = k (constant) T (absolute temperature)}, so if you want to repeatedly add a stable amount of gas by controlling the volume of the gas added to the molten resin in the heating tube, it is better to keep the device in Figure 52 and the pipes 232 and 233 at a constant temperature. The device in Figure 52 has its operation program built into the PLC of the molding machine. A separate controller can also be installed to exchange signals with the molding machine.

[0314] (Embodiment 37) There are reports that when manufacturing PET bottles, the preform is foamed to block light. In this case, the foaming agent used for foaming can be either gas (e.g. nitrogen gas, carbon dioxide gas) or liquid. However, since it is necessary to clean the surface by blow molding, it is preferable to use GCP during the injection foaming molding of the preform to make a preform without swirl marks. The foaming agent used for thick-wall molding using PET-G (G-PET) can be liquid (water, ethanol) or solid, and the effect of GCP can be fully demonstrated.

[0315] (PP) This is an explanation of PP, an olefin-based resin. PP homopolymer is a polymer made only from propylene. However, the raw material propylene may contain a small amount of ethylene, or a small amount of ethylene may be added at the start of polymerization, but this ethylene is excluded as if it did not exist. Random PP is made by mixing propylene with ethylene and polymerizing it. If you keep adding more and more ethylene, it will turn into rubber. The term was coined to refer to a block polymer of block propylene and ethylene-propylene rubber, but in reality it is a mixture with an island structure in which particles made of rubber and ethylene are dispersed in a homopolypropylene matrix, and is not a block polymer. The term block polypropylene does not exist overseas and is only used in Japan. When rubber is added to homogeneous PP, it is not called block PP, but is always a product that has been polymerized to completion.

[0316] (Embodiment 38) The inside of the sealing mold shown in Figure 20 was pressurized to 1 MPa using air, and then a foamable resin made by adding water to PP containing 20 wt.% talc to give it foamability was filled into the cavity, and as soon as filling was completed, the air pressure inside the mold was released into the atmosphere. The surface of the obtained foam-molded product containing 20 wt.% talc was somewhat thinner than that of a general molded product and a foam-molded product not using GCP, but it was not possible to completely sink the talc into the resin.

[0317] When 1.5 wt.% of ethanol was used instead of water, no floating of talc was observed on the surface of the foam-molded product, and all of the talc was submerged in the resin. Next, a material (PP) with talc content increased to 60wt.% was injection molded using 2wt.% ethanol. The GPC pressure was 1MPa inside the mold. Even though the talc content was increased to 60wt.%, there was no talc floating on the surface of the molded product, and all of it was sunk into the molded product.

[0318] In this way, the use of ethanol in molding PP resin containing talc greatly increases the fluidity of the molten resin. By adding a GCP of air with a pressure of about 1 MPa, the talc sinks and a foamed product with a good appearance can be obtained. This is because ethanol has a higher solubility in PP than water.

[0319] When carbon dioxide gas is used instead of air in the GCP, the carbon dioxide gas in the cavity penetrates into the molten resin from the flow front of the molten resin, improving the fluidity of the molten resin, making the talc more likely to sink than when air is used in the GCP. Based on the results of the GCP using carbon dioxide, the inventor used propane at about 1MPa as the compressed gas. Since propane is a flammable gas, there is a risk of explosion when it is mixed with air, so the cavity was pressurized with 1MPa of nitrogen gas in advance, vented to the atmosphere, and the inside of the mold was replaced with nitrogen gas. Next, the inside of the mold was pressurized (compressed air) using propane at a pressure of 2MPa. PP containing 60wt.% of talc, which had been given foaming properties with 2wt.% of ethanol, was filled in, and the propane in the mold was vented to the atmosphere as soon as filling was completed. The surface of the obtained molded product was a beautiful foamed molded product with no swirl marks or floating talc. This example of GCP using propane was carried out with the aim of confirming the GCP effect of propane (sinking talc), and it should be noted that there is a risk of fire and explosion in mass production.

[0320] In the case of PP resin containing environmentally degradable components such as paper pulp described in this invention other than the talc-containing PP mentioned above, in the case of injection molding processing, ethanol is used and the environmentally degradable components do not float to the surface, but can be somewhat submerged when using a GCP using air or nitrogen gas. The action and effect is particularly large when using a GCP using carbon dioxide gas. The inventor molded a PA-62 glass fiber 50% material with air at 1.2MPa GCP and ethanol and tap water as the foaming agent, and confirmed that the glass fiber float on the surface was greater in the case of ethanol than in the case of tap water. This does not match the previous case of PP talc. The combination of the resin to be foamed and the liquid needs to be changed depending on the resin used.

[0321] (Embodiment 39) In the above embodiment 38, it was confirmed that the fluidity of the molten resin increases when a liquid is used as a foaming agent. Therefore, embodiment 39 shows that a liquid is used as a fluidity improver rather than a foaming agent. In general molding, in the case of a resin with low fluidity, the effect of the resin's holding pressure is high near the gate and low at the end of the flow. In other words, flash is formed on the PL near the gate and large sink marks appear at the end of the flow. The molding shrinkage rate is small near the gate and large at the end of the flow, so the dimensional variation is large. In this way, a difference occurs between the pressure applied near the gate (holding pressure effect) and the pressure at the end of the flow (holding pressure effect), and the distortion (stress) inside the molded product is large, resulting in large warping and deformation of the molded product. However, by simply mixing a few wt.% or vol.% of alcohol or the like into the molten resin (plasticized and measured), the fluidity of the molten resin increases, making it easier to fill the cavity, thereby reducing the previously mentioned burrs, sink marks, dimensional variations due to differences in molding shrinkage rates, warping, and deformation.

[0322] A specific method of improving fluidity using liquid is explained. Using a sealed mold as shown in Figure 20, air, nitrogen gas, or carbon dioxide gas is used to pressurize the inside of the mold to above atmospheric pressure. A GCP is applied. The mold is pressurized. A resin with foaming properties and increased fluidity using, for example, alcohol is filled in the mold, and the GCP is vented at the very last moment when swirl marks do not occur. N...

Claims

1. A step of filling a foamable resin and / or a non-foamable resin into the cavity; A step (injection step) of injecting a gas (air) at a high (high) pressure, which is pressurized to a pressure equal to or higher than atmospheric pressure, into the foamable resin or non-foamable resin filled in the cavity during or after the filling is completed. A process of trapping the injected gas inside (a retention process); A process of exhausting the high pressure gas injected inside from the injection port (a process of natural exhaust); After the gas is exhausted into the atmosphere, the gas inlet is moved away from the molded product and the residual pressure inside the hollow portion is made equal to atmospheric pressure (a process of exhausting the gas by providing an exhaust circuit); After the molten resin in the cavity has cooled and solidified, the mold is opened and the molded product is removed (demolding process). A manufacturing method for resin molded products that have a foam layer and / or a hollow portion (layer) inside.

2. The mold used in the method for manufacturing a molded product according to claim 1 includes two or more sets of ejector plates, one of which has: The ejector pins that release the molded product are installed in the ejector plate, and the gas injection pins are installed in the other ejector plate. Another ejector plate incorporating a gas injection pin is provided with a mechanism that allows it to move forward and backward at any time.

3. In claim 1 and claim 2, the following are included: The gas injection mechanism, which injects high pressure gas into the molten resin in the cavity, can move forward and backward. A mechanism for advancing the reference numbers 117, 118, and 120; A mechanism for retracting it is provided, which is implemented by a mechanism built into the molding machine and / or mold.

4. The mold according to claim 1 is placed on a molding machine (injection molding machine), The advancement of the gas injection pin according to claim 2 is performed by a mechanism of an ejector rod of the molding machine, A gas with a large pressure is injected into the foamable resin and / or the non-foamable resin filled in the cavity, and is retained as necessary. After that, the gas is exhausted. The ejector rod moves backward. As a result of this ejector rod moving backward, the gas in the hollow portion is completely exhausted and the pressure becomes equal to the external pressure.

5. The advancement and / or retreat of the gas injection mechanism described in claim 2 is effected by urethane rubber, springs, gas springs, hydraulic or pneumatic cylinders, or other mechanical mechanisms installed within the mold, and the program for this operation is incorporated into a sequencer within the molding machine and is operated by the sequencer incorporated within the molding machine.

6. A sealed mold is used, the mold is closed, and gas with a pressure higher than atmospheric pressure is poured into the mold, a step of filling the cavity with a foamable resin having foaming properties by using a foaming agent having gaseous and / or liquid and / or solid properties into the gas-filled cavity; A step (injection step) of injecting a high (high) pressure gas pressurized at a pressure equal to or higher than atmospheric pressure into the foamable resin filled in the cavity during or after the filling is completed; A process of trapping the injected gas inside (a retention process); A process of exhausting the high pressure gas injected inside from the injection port (a process of natural exhaust); After the gas is exhausted into the atmosphere, the gas inlet is moved away from the molded product, and the residual pressure inside the hollow portion is made equal to atmospheric pressure (a process of exhausting the gas by providing an exhaust circuit); After the molten resin in the cavity has cooled and solidified, the mold is opened and the molded product is removed (demolding process). A manufacturing method for resin molded products that have a foam layer and / or a hollow portion (layer) inside.

7. 7. The method for producing a resin molded product according to claim 6, wherein a non-foaming resin is used.

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