JP2007038423A - Method for producing fluorocarbon resin molding and fluorocarbon resin molding produced by the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a high quality fluorocarbon molding and the molding produced by the method. <P>SOLUTION: In the method for producing the fluorocarbon resin molding, an admixture containing at least two perfluoroalkanes expressed by C<SB>n</SB>F<SB>2n+2</SB>(n: 6-12) is used as a molding auxiliary for fine PTFE powder, a sheet-shaped molding is produced by paste extrusion molding and rolled by a calender roll into an unbaked, semi-baked, or baked polytetrafluoroethylene film of 1-25 μm in thickness. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a fluororesin molded product and a fluororesin molded product produced by the production method.

  Conventionally, the following techniques have been proposed as a method for producing a thin film (25 μm or less) of polytetrafluoroethylene (hereinafter simply referred to as “PTFE” in the present specification).

  Method for making PTFE sintered block: As a method for producing this PTFE film, a skiving method for obtaining a film by cutting a block sintered body by compression molding of PTFE powder so as to peel off is known. In this method, it is difficult to directly obtain a film having a thickness of 50 μm or less, and secondary rolling treatment is necessary. Japanese Patent Application Laid-Open No. 56-24431 proposes this secondary processing method, in which a film is produced by cutting from a sintered block of PTFE, and subsequently heat-treated above the melting point of PTFE. Although it has been disclosed that a film having a thickness of 50 μm is further thinned by a rolling process at a temperature of 300 ° C. or more and having a pair of different roll speeds, it has been difficult to reduce the thickness of the film to less than 20 μm.

  Method of producing by casting from a dispersion of PTFE particles: This PTFE film is produced by applying an aqueous dispersion of PTFE particles on a substrate such as a glass plate or a polyimide film, and containing a surfactant. In this method, after the media are dried and removed, the film is further sintered at a temperature equal to or higher than the melting point of PTFE particles (industrially, a temperature of 350 ° C. or higher) and then peeled off from the substrate. However, since PTFE particles are simply agglomerated, there are many voids in the molded film, and the strength of the tensile test and the like is weaker than the film obtained by the PTFE calender, and it is pointed out that peeling is difficult. Japanese Patent Laid-Open No. 9-278927 proposes to solve the problems of casting film difficulty and film smoothness. However, this proposal requires a new problem that a layer soluble in an organic solvent must be provided between the PTFE membrane and the substrate.

Therefore, as a manufacturing method for solving the above-described problems, a method of manufacturing a PTFE stretched porous membrane by heating and pressurizing has been proposed (Japanese Patent Laid-Open No. 2002-275280). The production method is obtained by removing the molding aid from the paste molded body obtained by mixing the fine powder of PTFE with the molding aid, stretching at a high temperature and high speed, and further firing if necessary. The uniaxially or biaxially stretched porous PTFE film is compressed (pressurized) at a temperature below its melting point in the first compression step, and compressed (pressurized) at a temperature equal to or higher than the melting point of PTFE in the second compression step. Thus, a thin film is obtained.
JP2002-275280

  However, the above manufacturing method uses a PTFE powder paste extrusion, a molding auxiliary agent removal, and a stretched porous PTFE film that has been stretched (calcined if necessary) as a raw material, and then passed through a first compression step and a second compression step. There is a problem that a film is obtained and the process is long and complicated.

  As one of the reasons why this process becomes long and complicated, in the conventional manufacturing method, a hydrocarbon-based petroleum solvent has been used as a molding aid for PTFE fine powder paste extrusion. However, when this hydrocarbon-based petroleum solvent is used, a thickness of 30 μm is the limit of industrial production by drawing. Moreover, when manufacturing a spaghetti tube, the drawing ratio was about 1/3000.

  That is, the essence of molding using PTFE fine powder paste extrusion and extrudate calender rolls is the aid of lubrication between the particles of approximately spherical particles 0.2 to 0.3 μm in diameter obtained by emulsion polymerization of PTFE. As described above, a PTFE molded body is obtained by drawing using a liquid as a medium, or rolling a sheet obtained by drawing. As this liquid, a hydrocarbon solvent or oil is used. However, the surface energy of the hydrocarbon system and the surface energy of the PTFE particles are so far apart that they are lubricated at the extreme pressure between the PTFE particles at the time of paste extrusion processing with a large drawing ratio and at the time of rolling the thin wall of the paste extrudate. For this reason, the hydrocarbon-based lubricating film (also referred to as an oil film) formed for this purpose is destroyed and eliminated, so that there is the above-mentioned limit.

  The present invention provides a method for producing a fluororesin molded article that facilitates rolling to obtain a thin PTFE film by using PTFE fine powder as a raw material and using a fluorine-based solvent as a molding aid. It is in.

  The above-mentioned fluororesin molded product by paste extrusion molding is an auxiliary mixture mixing and aging process that uniformly covers the surface of primary particles formed by emulsion polymerization with a molding aid, and obtains a finely packed state of primary particles without breaking the shape of the primary particles. In order to achieve this, the paste extrusion process and the rolling process to align the primary particles in laminar drawing and calendering, the drying process to remove the lubricant present in the gap between the finely packed particles, the melting point of the polymer A sintering process that forms a uniform molten layer by filling the gaps between the particles with the slow free movement of the molecules that make up the crystal, and a finishing process that cools the melting point to below the melting point of the fired body. It is manufactured through each process.

  The problem of close-packing of emulsion-polymerized particles in paste extrusion molding begins with considering the state of particle packing. If a close-packed state of particles can be obtained, a molded product can be obtained. Assuming that the size of the primary particles is 0.2 μm true sphere and the density is 2.3 (crystallinity 99%), the fine packing porosity is 25.95% and the apparent specific gravity is 1.7. In the case of the primary particles having an ellipsoidal shape, when the closest packing void ratio is 30.19%, it is 1.60. The raw tape powder is mainly composed of elliptical particles, and the specific gravity of the raw tape is 1.55 level, which is slightly smaller than the theoretical value. However, the close-packing in an actual unsintered molded product deviates from the theoretical value for complex reasons such as sphere and size.

  The proper amount of auxiliary agent is an amount necessary for forming a lubricating skin layer covering the surface of the primary particles, and the auxiliary agent cannot be contained in crystals having 98% or more of the primary particles. Therefore, the amount of auxiliary agent is proportional to the specific surface area of the powder. The specific surface area of the PTFE primary particles is round and the larger the particle size, the smaller the amount of auxiliary agent.

  In the skin layer, particles flow through a molding aid during extrusion flow. The thickness of the liquid film that is not subjected to shear deformation is the minimum necessary amount of the skin layer. When the amount of the auxiliary agent is insufficient, the extrusion pressure is abnormally increased. When the amount is extremely reduced, the primary particles are no longer present in the molded product. The phenomenon that causes shearing of the skin layer is often observed as a devitrification whitening phenomenon during a raw tape calendar.

  Therefore, the type of auxiliary agent also affects the rollable thickness (thickness at which devitrification whitening occurs). Conventionally, the industrial film thickness obtained by calender molding from PTFE fine powder using a petroleum-based solvent was at most 30 μm. In addition, the type of auxiliary agent is determined by whether it is processed like a rolled tape, or processed like electric wire coating, or the processing method and process, but the auxiliary agent condition may have a subtle effect.

  The drying speed affects the production speed, and some of the evaporation residue is colored, and the rapid volatilization of the auxiliary agent causes blistering and deteriorates the mechanical strength and electrical insulation characteristics together with the whitened portion.

  The present invention has produced a technique for greatly improving the above-mentioned matters, which has been a conventional problem. That is, even if the surface of the primary particles is covered with an auxiliary agent, a strong affinity between the PTFE surface and the auxiliary agent is necessary, so a fluorinated solvent is suitable, and in particular, a PFC solvent having the same structure as PTFE has the strongest affinity. The skin layer does not break down due to the local pressure resistance of the oil film, and the mixed PFC with a wide boiling range does not cause blistering due to the volatile of the auxiliary agent, and the generation of whitening occurs up to the 1 μm film thickness. Furthermore, the present inventors have found that it is the most excellent processing aid in that no residue is left.

  Also, the primary particles must flow independently and laminarly during extrusion, and if the particles are connected in a conglomerate form, they become turbulent and a continuous smooth molded product is obtained. There are no problems, and the cause of the particles becoming agglomerate is due to the vibration of the raw material powder, distribution process vibration, storage temperature, long-term storage at a transition point of 21 ° C. or higher, etc. The fluorine-based solvent of the present invention is contained in the PTFE powder. It has been devised that the quality defects due to these can be greatly solved since it sufficiently penetrates the surface of PTFE primary particles.

  Furthermore, high-viscosity auxiliary agents such as liquid paraffin and perfluoropolyether, such as demnum (manufactured by Daikin Industries), florinart (manufactured by 3M) or fomblin Y (Audimont), etc. In rolling tape processing formed using a high-boiling auxiliary agent, the concentration distribution of the auxiliary agent tends to exist, and appears as a change in the meandering, width, and thickness of the tape during rolling, resulting in a problem of quality deterioration. When the fluorine-based solvent in is used, the above-described quality deterioration does not occur.

  When the FP is extruded and rolled under pressure, the primary particles that come into contact with the mold surface are sheared and broken to form a continuous film. During drying, the auxiliary agent passes through this continuous layer and goes outside. Since blisters and surface cracks occur when the auxiliary agent passes suddenly, it is necessary to prevent rapid drying. However, the mixed PFC having two or more molecular weights of the present invention can be dried stepwise. Because it is possible, it is hard to generate a blister.

  When a solvent with a single boiling point reaches the boiling point temperature, it vaporizes and vaporizes all at once, but the change in the evaporation rate of mixed solvents with different boiling points starts at the boiling point on the low boiling side and the boiling point on the high boiling side. As the end point, the concentration changes in proportion to the partial pressure during that period, and only the partial pressure is vaporized below this boiling point temperature. Against the backdrop of these properties, the solvent as a molding aid used for PTFE paste extrusion needs to prevent vaporization of the solvent at the temperature of the normal working process and vaporize and evaporate in the drying process. This means that if the auxiliary agent is not sufficiently dried before entering the sintering step, particularly in the step where drying and sintering are continuously performed, the surface of the molded product may be torn by rapid evaporation of the auxiliary agent, Alternatively, the auxiliary agent is decomposed and the quality (chemical property, physical property, mechanical property) of the molded product is deteriorated, or flammable solvent is ignited. Therefore, the drying process is important for paste extrusion molded products. On the other hand, the surface of the molded product obtained by extrusion and rolling of the paste is formed into a film as a dense film without primary particles of PTFE becoming fibrillated and remaining in the form of particles. This film exists as a barrier for gasification and diffusion of the auxiliary agent, and rapid gasification destroys the dense film. Therefore, it is necessary to gradually perform gasification diffusion of the auxiliary agent. Therefore, a solvent having a boiling range is selected in the process of removing the auxiliary agent by heating. For example, petroleum solvents with a boiling range are used for forming aids for thin tubes called spaghetti tubes, such as when coating metal wires with PTFE fine powder (the Exfoliant Isopar E boiling point range for Polyflon Handbook of Daikin Industries, Ltd.) 115 ° C. to 142 ° C. are recommended). In the present invention, a mixed solvent having two or more boiling points at the same time as the affinity of perfluoroalkane having the same structure as PTFE prevents separation due to extreme pressure applied to PTFE particles in the molding process, and moderates gasification diffusion in the drying process. It is in having found out what to do.

  The method for producing a fluororesin molded product according to the present invention is characterized by being produced by paste extrusion molding using a fluorine-based solvent as a molding aid for PTFE fine powder.

  In the above manufacturing method, a molded product manufactured by paste extrusion molding using a fluorine-based solvent as a molding aid for PTFE fine powder is rolled with a calender roll, and an unfired, semi-fired or fired PTFE film having a thickness of 25 μm to 1 μm You may make it shape | mold.

  Further, in the above manufacturing method, paste extrusion molding may be performed with a molding die that gives orientation to two axes.

  Furthermore, in said manufacturing method, you may orient in two axes | shafts of the rotation direction of a calender roll and the direction orthogonal to this rotation direction.

Moreover, as the fluorine-based solvent used in the above production method, it is desirable to use a mixture containing at least two perfluoroalkanes represented by C _n F _{2n + 2} (n: 6 to 12).

Furthermore, the mixing ratio of two kinds of perfluoroalkanes represented by C _n F _{2n + 2} (n: 6 to 12), which is the above mixture, is low molecular weight C _n F _{2n + 2} 10 to 50%, high molecular weight C _n F _{2n + 2} is preferably 50 to 90%.

  Moreover, it is desirable that the fluorine-based solvent used in the above production method is a mixture containing two types of fluorine-based solvents having a boiling point of 50 ° C. or higher and 180 ° C. or lower.

  Furthermore, it is desirable that the mixing ratio of the two types of fluorine-based solvents having a boiling point of 50 ° C. or higher and 180 ° C. or lower is 10 to 50% for low boiling point components and 50 to 90% for high boiling point components.

  The fluororesin molded product according to the present invention is manufactured by the above-described fluororesin molded product manufacturing method.

In the present invention, a perfluoroalkane solvent represented by C _n F _{2n + 2} (n: 6 to 12) having the same chemical structure as that of PTFE particles, mainly an admixture of C ₆ F ₁₄ and C ₁₂ F ₂₆ has a chemical interaction. However, the above-mentioned phenomenon is solved by forming an extruded product using the perfluoroalkane solvent as a molding aid for PTFE paste extrusion.

  It is possible to prevent oil film breakage between PTFE particles that occurs when the above-mentioned extruded product is rolled with a calender roll, and to obtain a thin film while maintaining lubrication.

In addition, by making the perfluoro solvent mainly a mixture of C ₆ F ₁₄ and C ₁₂ F ₂₆ , the perfluoroalkane solvent is dried and removed by heating at about 120 ° C. after rolling with a calender roll, thereby forming a thin PTFE film. Obtainable. By the way, when a perfluoroalkane solvent with a single molecular weight is used, evaporation occurs momentarily during drying, and blistering or balloon-like blistering tends to occur. Deteriorating quality such as rough skin on the surface.

More importantly, the perfluoroalkane solvent is a mixture of C ₆ F ₁₄ and C ₁₂ F ₂₆ , and the perfluoroalkane C ₆ F _{14 has} a boiling point of 56 ° C. and the boiling point of C ₁₂ F ₂₆ is 117 ° C. It is a thing. Since this admixture has a strong chemical interaction with PTFE particles, it is not easily separated at room temperature, and is excellent in processability at room temperature. Others such as n-hexane having an equivalent boiling point are scattered quickly and are difficult to process in an open system. Further, by heating to the boiling point, the molding aid can be easily removed and recovered from the molded product sequentially. In a single substance, bumping occurs during drying, and C ₁₂ F ₂₆ is solid up to the boiling temperature and cannot be mixed with the powder of PTFE particles at room temperature. In addition, there is a perfluoroether oil, demnum (manufactured by Daikin Industries, Ltd.), which has the same level of surface energy as the admixture, but it has a low vapor pressure and a high boiling point, so that it is dried by normal heating. There are difficulties.

  In paste extrusion molding in the production of fluororesin molded products as in the present invention, a fluorine-based solvent is used as a molding aid, so that a high-quality thin-film PTFE film is obtained without requiring complicated processes as in the prior art. It became possible.

As the fluorine-based solvent in the present invention, a chemical name perfluoroalkane represented by C _n F _{2n + 2} (n: 6 to 12), a fluorine-based inert liquid, a chemical name perfluoropolyether (an example of a structural formula: CF ₃ − ((O—CF ₂ —CF ₂ ) _n — (O—CF ₂ ) _m ) —O—CF ₃ ), chemical name hydrofluoropolyether (example of structural formula: HCF ₂ O— (CF ₂ O) _p ( _{CF 2 CF 2 O) q -CF} 2 H) can be mentioned. In addition, the mixing ratio of two types of perfluoroalkanes represented by C _n F _{2n + 2} (n: 6 to 12) is low molecular weight C _n F _{2n + 2} 10 to 50%, high molecular weight C _n F _{2n + 2} 50 to 90%. For example, two types of C ₆ F ₁₄ of about 20% and C ₁₂ F ₂₆ of about 80% and a mixture of some C ₈ F ₂₀ and C ₁₁ F ₂₄ can be preferably used.

Further, as the fluorinated solvent in the present invention, an admixture containing at least two kinds of fluorinated solvents having a boiling point of 50 ° C. or higher and 180 ° C. or lower is used. Among them, the boiling point of perfluoroalkane C ₆ F ₁₄ is 56 ° C., A perfluoroalkane C ₁₂ F _{26 has} a boiling point of 117 ° C., and a mixture containing these two kinds of fluorine-based solvents is preferable.

  Hereinafter, the Example of the manufacturing method of the thin film PTFE film based on this invention is explained in full detail.

a: Mixing of molding assistant PTFE fine powder F-104 (manufactured by Daikin Industries, Ltd.) 1 Kg was passed through a 10-mesh sieve and placed in a 5-liter wide-mouth polyethylene container. Next, 100 parts by weight of fine powder was mixed with perfluoroalkane, which is a fluorinated solvent as a molding aid (about 20% for C ₆ F _{14 and} about 80% for C ₁₂ F ₂₆ and some C ₈ F ₂₀ ). 590 g (a proportion of 59 parts by weight) of the mixture of C ₁₁ F ₂₄ ). The specific gravity of perfluoroalkane is 2.0, and the mixing ratio is matched to the volume of the petroleum solvent. In addition, a series of work from the auxiliary agent mixing to the paste extrusion step was performed in an air-conditioned room at 25 ° C. Since PTFE has a transition point at 19 ° C., it is usually handled at a temperature of 2 to 3 ° C. or more from this transition point.

b: Paste extrusion molding After 48 hours have passed after mixing of the auxiliary agent, the sheet is extruded using the paste extrusion molding machine A shown in FIGS. The paste extrusion molding machine A has a cylinder 1 made of a square cylinder having an inner cross-sectional shape of 75 mm square on one side, a tapered taper die 2 connected to the lower part thereof and having an angle θ of 60 degrees, and the cylinder 1 is filled. And an extrusion ram 3 for extruding a filler P made of a PTFE fine powder and a molding aid mixed with the powder. The die land at the tip of the taper die 2 has a short side of 5 mm and a long side of 75 mm. Since the rectangular shape is 30 mm, the aperture ratio is 15: 1. Then, as shown in FIG. 2, the cylinder 1 was filled with a filler P containing PTFE fine powder, and the sheet S was extruded from the tip of the taper die while being pressurized at a lowering speed of 20 mm / min of the extrusion ram 3. It should be noted that, in order to ensure that the paste is uniformly distributed in the powder for good paste extrusion molding, it is usually preferable to perform after 48 hours, although it depends on the vapor pressure and penetration rate of the aid. Moreover, you may make it make a biaxial crossing of an extrusion sheet using what expanded the die land of the front-end | tip part of a taper die in the width direction.

c: Rolling of Extruded Sheet Next, the process of rolling the extruded sheet S with the calendar roll R will be described. After heating the extruded sheet S created by the above extrusion molding in a constant temperature water bath at 50 ° C. for 30 minutes, the sheet S1 is cut into a length of 100 mm along the extrusion direction L, and the cut sheet S1 is shown in FIG. The sheet S1 is rolled to a predetermined thickness by being inserted into a calender roll R composed of rolling rolls R1 and R2 heated to a pair of upper and lower surface temperatures of 50 ° C. The rolling rolls R1 and R2 are rolls having a surface finish of 0.1 μm and rotate at a circumferential speed of 5 m / min with a width of 350 mm and a diameter of 300 mm, and the gaps can be adjusted until the rolls come into contact with each other. It has become. When inserting the sheet S1 into the calendar roll R, the calendar roll R so that the width direction W of the sheet S1 perpendicular to the extrusion direction L of the sheet S1 and the rotation direction H of the rolling roll as the calendar roll R are the same direction. So that the two axes of the extrusion direction L and the width direction W are crossed. When the gap between the rolling rolls R1 and R2 of the calender roll R is appropriately changed to change the rolling thickness, the rolled sheet S2 has almost no change in width and has a thickness of 50 μm, 30 μm, 20 μm, 10 μm, and 5 μm. A film that did not occur could be obtained continuously. Moreover, when the width of the cutting sheet was 20 mm, a film similar to the above was continuously obtained with a thickness of 2 μm.

d: Drying and sintering of sheet aid Each of the films prepared was cut to a length of 50 cm, placed on an aluminum plate, sandwiched between clips, and heated in a hot air oven at 200 ° C. for 10 minutes. The auxiliary was dried and then calcined in a hot air oven heated to 360 ° C. for 15 minutes. As a result, each sintered transparent film was obtained. In some cases, it may be used as an unfired film without firing, or as a semi-fired film.

Comparative Example 1

a ': Mixing of molding aids PTFE fine powder F-104 (Daikin Kogyo Co., Ltd.) 1 kg was mixed with 230 g of petroleum solvent Isopar M (Exxon) as a molding aid (the volume ratio was the same as in the examples). The specific gravity of Isopar M was 0.78). The procedure was the same as in the example except that the molding aid was changed.

b'c ': Paste extrusion molding and rolling Paste extrusion and rolling were performed in the same manner as in the examples. Film thicknesses of 50 μm and 30 μm were formed in the same manner as in the examples, but the film was devitrified at 20 μm and 10 μm. The 5 μm film was torn or cut, and a continuous sheet could not be obtained.

d ′: Drying and Sintering of Sheet Auxiliary Agents The continuous films obtained above were dried and fired in the same manner as in the Examples. As a result, a transparent sintered film could be obtained when the film thickness was 50 μm and 30 μm, but the 20 μm and 10 μm films were whitened and opaque films. The 5 μm film could not obtain such a length for drying and baking.

Comparative Example 2

In the same manner as in the example, molding was carried out using only C ₆ F ₁₄ in perfluoroalkane in the order of steps a, b and c. However, the auxiliary sheet volatilized from the heated sheet surface, and devitrification occurred from 20 μm. Even after sintering of d, the film lacked transparency.

Comparative Example 3

C ₆ F ₁₄ in the perfluoroalkane was removed by rectification, but they were room temperature solids and could not be mixed with the powder.

  The fluororesin molded product manufactured by the manufacturing method of the present invention is used in various industrial fields for which applications have already been developed, and in particular, an insulating film for capacitors, a pellicle film for photoprinting of IC circuits, and an X-ray It can be suitably used for a medical film mixed with an impermeable substance, a conductive film mixed with a conductive substance, a coating film for communication lines, and a sliding coating film for OA equipment.

It is a schematic perspective view of an extrusion molding machine. It is a schematic sectional drawing which shows the state which is performing the extrusion molding with an extrusion molding machine. It is a schematic sectional drawing which shows the state currently rolling by the calendar roll.

Explanation of symbols

DESCRIPTION OF SYMBOLS A ... Paste extrusion molding machine 1 ... Cylinder 2 ... Taper die 3 ... Extrusion ram R ... Calender roll R1, Roll roll R2, Roll P: PTFE fine powder and this Filler made of molding aid mixed with powder S ... Extruded sheet S1 ... Sheet after cutting S2 ... Sheet after rolling L ... Sheet extrusion direction W ... Sheet width direction H ...・ Rolling roll rotation direction

Claims (9)

A method for producing a fluororesin molded product, characterized in that it is produced by paste extrusion molding using a fluorine-based solvent as a molding aid for polytetrafluoroethylene fine powder. A molded product produced by paste extrusion molding using a fluorine-based solvent as a molding aid for polytetrafluoroethylene fine powder is rolled with a calender roll, and an unfired, semi-fired or fired polytetrafluoroethylene film having a thickness of 25 μm to 1 μm A method for producing a fluororesin molded product, which is molded into The method for producing a fluororesin molded product according to claim 1 or 2, wherein paste extrusion molding is performed using a mold that gives orientation to two axes. The method for producing a fluororesin molded product according to claim 2, wherein the fluoropolymer molded product is oriented in two axes, a rotation direction of the calender roll and a direction orthogonal to the rotation direction. The fluorine-based solvent is an admixture containing at least two perfluoroalkanes represented by C _n F _{2n + 2} (n: 6 to 12), according to any one of claims 1 to 4. Manufacturing method of fluororesin molded product. The mixing ratio of two kinds of perfluoroalkanes represented by C _n F _{2n + 2} (n: 6 to 12) is 10 to 50% of low molecular weight C _n F _{2n + 2 and} 50 to 90% of high molecular weight C _n F _{2n + 2} The method for producing a fluororesin molded product according to claim 5. The fluororesin molded article according to any one of claims 1 to 6, wherein the fluorinated solvent is a mixture containing two fluorinated solvents having a boiling point of 50 ° C or higher and 180 ° C or lower. Method. 8. The fluorine according to claim 7, wherein the mixing ratio of the two types of fluorine-based solvents having a boiling point of 50 ° C. or higher and 180 ° C. or lower is 10 to 50% of low boiling point components and 50 to 90% of high boiling point components. Manufacturing method of resin molded product. A fluororesin molded product produced by the method for producing a fluororesin molded product according to any one of claims 1 to 8.

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