Abstract: There is provided a method for producing a resin particle capable of unprecedentedly realizing both excellent heat resistant keeping property and melting property. The present invention is a method for producing a resin particle (X) comprising the step of treating a resin particle (B) containing a resin (A) composed of a crystalline part (a) containing, as an essential constitutional component, a polyester (p1) not containing an aromatic ring or a polyester (p2) containing an aromatic ring, and produced by polycondensation of a polyol component and a polycarboxylic acid component, and a noncrystalline part (b), with liquid or supercritical carbon dioxide (C), and removing (C), wherein a heat of fusion measured by differential scanning calorimetry (DSC) of the obtained (X) satisfies the following relational formula (1): 0?H2/H1?0.

Abstract: There is provided a method for producing a resin particle capable of unprecedentedly realizing both excellent heat resistant keeping property and melting property. The present invention is a method for producing a resin particle (X) comprising the step of treating a resin particle (B) containing a resin (A) composed of a crystalline part (a) containing, as an essential constitutional component, a polyester (p1) not containing an aromatic ring or a polyester (p2) containing an aromatic ring, and produced by polycondensation of a polyol component and a polycarboxylic acid component, and a noncrystalline part (b), with liquid or supercritical carbon dioxide (C), and removing (C), wherein a heat of fusion measured by differential scanning calorimetry (DSC) of the obtained (X) satisfies the following relational formula (1): 0?H2/H1?0.

Abstract: Process for producing fluorinated olefins from fluorinated materials, the process comprising thermally decomposing the fluoropolymers into fluoroolefins in a reactor having a feeding zone where the fluorinated materials are fed into the reactor and a decomposition zone where the fluorinated materials are thermally decomposed and wherein the thermal decomposition is carried out in the presence of microwave irradiation.

Abstract: A process for making a carbonaceous material and a carbonous residue from scrap tires is disclosed. Tires are digested in an oil product. Steel and glass fibers are separated. A product enhancing additive comprising halogen based organic or inorganic compounds is added. The resulting carbonaceous material is then cured to create the final product. The produced carbonous residue is well suited for capture of mercury. The present invention has the benefits of providing a use for scrap tires that would otherwise require disposal in a landfill, and also produces a product useful for capturing a harmful element, thereby providing multiple environmental and economic benefits.

Abstract: The present invention relates to a preparation method for a biodegradable polymer microparticle and a microparticle prepared by the method. More particularly, the present invention relates to a method for preparing a polymer microparticle, wherein the method includes the steps of: dissolving a biodegradable polyester-based polymer in DMSO (Dimethyl Sulfoxide); spraying the solution in a low temperature hydrocarbon solution to provide a frozen DMSO microparticle; adding the microparticle in a low temperature salt aqueous solution to dissolve DMSO; and removing salt. The present invention provides a method for preparing a novel polymer microsphere which can be injected through a syringe due to excellent physical properties (such as biocompatibility, biodegradability, porosity, mechanical strength) and the microcarrier's size-adjustability, and can be easily mass-produced.

Abstract: Method and apparatus for thermally processing polyester pellets, e.g., polyethylene terephthalate pellets, in order to achieve a partial crystallization, whereby the polyester melt is fed to an underwater pelletizer and pelletized, the pellets obtained are fed to a water/solids separating device and the dried pellets are fed at a pellet temperature of greater than 100°C. to an agitation device that the pellets leave at a pellet temperature of over 100°C.

Abstract: There is provided a method for producing a resin particle capable of unprecedentedly realizing both excellent heat resistant keeping property and melting property. The present invention is a method for producing a resin particle (X) comprising the step of treating a resin particle (B) containing a resin (A) composed of a crystalline part (a) containing, as an essential constitutional component, a lactone ring-opening polymer (p), and a noncrystalline part (b), with liquid or supercritical carbon dioxide (C), and removing (C), wherein a heat of fusion measured by differential scanning calorimetry (DSC) of the obtained (X) satisfies the following relational formula (1): 0?H2/H1?0.9??(1) [in the relational formula (1), H1 represents a measurement value of a heat of fusion (J/g) at the time of the initial temperature elevation measured by DSC; and H2 represents a measurement value of a heat of fusion (J/g) at the time of the second temperature elevation measured by DSC].

Abstract: A method and device for reprocessing used plastic containers, especially PET bottles, by analyzing the degree of contamination of the plastic, determining the decontamination process parameters as a function of the degree of contamination found in the analyzing step, and conducting a controlled decontamination of the plastic according to the decontamination process parameters thus determined. With this method and this device, it is thus possible to perform the decontamination process step in a controlled manner, yielding a more economical reprocessing method.

Abstract: Embodiments of the invention provide a process for processing post-consumer polymer. The polymer is contacted with a control medium having a carrier gas and a reactive vapor. Such a process is useful for processing post-consumer polymers with lower energy and reactants than with liquid reactants, and also promotes decontamination of the recycled polymer during the reaction.

Abstract: The invention provides methods and systems for manufacturing low-acid polyalkylene terephthalate, for example, polybutylene terephthalate (PBT). The invention also provides methods and systems for preparing macrocyclic polyester oligomer (MPO) from low-acid polyalkylene terephthalate. Finally, the invention provides methods and systems for preparing MPO via reaction of a diol and a dialkyl ester in an organic solvent to form non-isolated, low-acid polyalkylene terephthalate which undergoes cyclization (depolymerization) to form MPO.

Abstract: Polyester-carbonate copolymers are prepared by copolymerizing lactide with a 1:4-3:6 dianhydrohexitol in the presence of a carbonate precursor and a polymerization catalyst. The copolymers have an elevated glass transition temperature, relative to polylactide resins.

Abstract: A method for producing a composite nanoparticle, including the steps of: changing the conformation of a dissolved polyelectrolyte polymer from a first extended conformation to a more compact conformation by changing a solution condition so that at least a portion of the polyelectrolyte polymer is associated with a precursor moiety to form a composite precursor moiety with a mean diameter in the range between about 1 nm and about 100 nm; and cross-linking the polyelectrolyte polymer of the composite precursor moiety to form a composite nanoparticle.

Abstract: A fine agglomerates mixture formed from pyrolysis of recyclable polymeric material such as scrap tires, polymeric automotive components, used rubber materials, and plastic containers. The mixture contains a carbon content ranged between about 80% to about 95% by weight of the fine agglomerates mixture. The fine agglomerates mixture has agglomerate particles averaging less than or equal to 35 nm. The fine agglomerates mixture also has a nitrogen surface area greater than or equal to 73 m2/g and includes an inorganic functional filler in a range between about 5% to about 20% weight of the fine agglomerates mixture.

Abstract: A process for producing a perfluoropolymer, the process including extruding a polymer obtained by polymerizing a perfluoromonomer to prepare strands, and bringing a gas comprising from 3 to 50 volume % of fluorine gas into contact with the strands; the process being conducted on an apparatus that includes an extruder for melting and extruding the polymer obtained by polymerizing a perfluoromonomer, a die having a plurality of pores for preparing the strands from the molten polymer extruded, and a fluorination tank for bringing the gas comprising from 3 to 50 volume % of fluorine gas into contact with the strands.

Abstract: Purification methods of polyamic acid resin and polyimide resin are provided. The purification methods of polyamic acid resin or polyimide resin includes providing a polyamic acid resin or a polyimide resin containing metal ion impurities. Thereafter, a cation exchange resin is used to react with the polyamic acid resin or the polyimide resin in order to remove the metal ion impurities therein, and a water content in the polyamic acid resin or the polyimide resin is removed to purify the polyamic acid resin or polyimide resin.

Abstract: Polyester compositions, especially polyethylene terephthalate homopolymer and copolymers, are disclosed containing titanium catalysts and catalyst deactivator added late in the manufacturing processing having reduced acetaldehyde generation rates. The polyester compositions are low in free acetaldehyde, making them suitable for fabrication into beverage containers for relatively tasteless beverages such as bottle water. Furthermore, the polyesters are polymerized to a high inherent viscosity in reduced processing time, without the necessity of further polymerization in the solid state, and in the absence of acetaldehyde scavengers leading to polyester polymers having reduced color.

Abstract: Integrated processes for making polyesters are disclosed, that include the steps of: (a) producing an aromatic polycarboxylic acid in a monomer production facility; (b) producing a polyester in a polyester production facility, wherein the producing of the polyester comprises the substeps of: (i) forming a polyester reaction medium comprising at least a portion of the aromatic polycarboxylic acid from the monomer production facility, (ii) subjecting at least a portion of the polyester reaction medium to one or more chemical reactions to thereby produce the polyester, (iii) heating the polyester reaction medium at one or more locations in the polyester production facility via indirect heat exchange with high-pressure steam, wherein the heating causes at least a portion of the high-pressure steam to condense and thereby provide pressurized condensed water, and (iv) flashing at least a portion of the pressurized condensed water to thereby produce lower-pressure steam; and (c) using at least a portion of the lower

Abstract: Methods for preparing active carbonate esters of water-soluble polymers are provided. Also provided are other methods related to the active carbonate esters of water-soluble polymers, as well as corresponding compositions.

Abstract: A method for producing a composite nanoparticle, including the steps of, collapsing at least a portion of a polyelectrolyte polymer in solution about one or more precursor moieties to form a composite precursor moiety having a mean diameter in the range between about 1 nm and about 100 nm, wherein the polyelectrolyte polymer has an extended conformation in a first solution state and a more compact conformation in a second solution state; and cross-linking the polyelectrolyte polymer of the composite precursor moiety to form a composite nanoparticle wherein the precursory moiety is a charged organic ion.

Abstract: It is an object of the present invention to produce a polylactic acid having a high molecular weight such as a weight average molecular weight (Mw) of more than 100,000 from which only a stereocomplex crystal is grown even by repeating melting and crystallization. The present invention is a process of producing a polylactic acid, including the steps of: (i) obtaining a solid by kneading together poly(L-lactic acid) and poly(D-lactic acid) at a temperature of 160 to 225° C. and crystallizing the kneaded product; and (ii) melt kneading the obtained solid.

Abstract: In one embodiment, the invention relates to a two step process in which a 1,4-butane diol component reacts with a polyethylene terephthalate component under conditions that depolymerize the polyethylene terephthalate component into a molten mixture and the molten mixture is placed under subatmospheric conditions that produce the modified polybutylene terephthalate random copolymers. In another embodiment, the invention relates to a three step process in which a diol component selected from the group consisting of ethylene glycol, propylene glycol, and combinations thereof reacts with a polyethylene terephthalate component under conditions sufficient to depolymerize the polyethylene terephthalate component into a first molten mixture; and where the first molten mixture is combined with 1,4-butane diol under conditions that create a second molten mixture that is subsequently placed under subatmospheric conditions that produce the modified polybutylene terephthalate random copolymers.

Abstract: An aromatic polyester resin composition, comprising: a melt-kneaded product of 99-70 weight parts of an aromatic polyester resin and 1-30 wt. parts (providing a total of 100 wt. parts together with the aromatic polyester resin) of a polyglycolic acid resin, wherein the composition is characterized by a transesterification rate CTE (%) of 20-60% determined by formula (1) below based on a peak integration ratio of methylene group in polyglycolic acid appearing at ?4.87 ppm with reference to tetramethylsilane according to 1H-NMR measurement: CTE (%)=(1?I(B)/I(A))×100??(1), wherein I (A): a peak integration ratio of the methylene group of the polyglycolic acid main chain with respect to the alkylene group of the aromatic polyester main chain calculated from the components weight ratio; and I (B): a peak integration ratio of the methylene group of polyglycolic acid main chain to the alkylene group of the aromatic polyester main chain in the resin composition.

Abstract: An ion-conducting layer for an actuator element including (I) a fluorine-containing polymer having a functional group and (II) an ionic liquid. The functional group is selected from —OH, —COOH, —COOR, —CN, iodine atom, epoxy group and (meth)acryloyl group, and is contained in a side chain and/or at an end of a trunk chain of the fluorine-containing polymer. Also disclosed is an electrode layer including (I) the fluorine-containing polymer having a functional group, (II) an ionic liquid and (III) an electroconductive nano-filler. Also disclosed is an actuator element including the ion-conducting layer and at least two electrode layers formed on the surfaces of the ion-conducting layer and insulated from one another, in which flection or deformation can be caused by applying an electric potential between the electrode layers.

Abstract: The invention relates to a process for making modified polybutylene terephththalate random copolymers from a polyethylene terephthalate component. The invention relates to a three step process in which a diol component selected from the group consisting of ethylene glycol, propylene glycol, and combinations thereof reacts with a polyethylene terephthalate component under conditions sufficient to depolymerize the polyethylene terephthalate component into a first molten mixture; and where the first molten mixture is combined with 1,4-butanediol under conditions that create a second molten mixture that is subsequently placed under subatmospheric conditions that produce the modified polybutylene terephthalate random copolymers. The invention also relates to compositions made from the process.

Abstract: The present invention concerns a process for the preparation of a silicone coating of low dielectric constant, comprising the following essential steps: a) a film-forming silicone composition is deposited on the surface of a substrate, said silicone composition comprising: (i) at least one crosslinkable film-forming silicone resin, (ii) at least one ?,?-hydroxylated, essentially linear silicone oil capable of degrading under the action of heat, and (iii) at least one solvent capable of rendering the silicone resin (i) compatible with the silicone oil (ii), b) the solvent (iii) is removed, preferably by heating, and, simultaneously or sequentially, c) the film-forming silicone composition is cured by heating. The invention deals also with a silicone coating obtained by this process and an integrated circuit comprising such a silicone coating as an electrical insulator.

Abstract: The invention provides a novel method for manufacturing iodinated resin particulates that have widespread utility as disinfectants. The invention also provides novel iodinated demand disinfectant iodinated resins that have superior properties than resins known in the art. The novel manufacturing process of the current invention is highly efficient and environmentally friendly and is conducted without the presence of water. Additionally, the manufacturing process produces iodinated resins that have better overall biological performance than resins produced by prior art methods owing to higher degrees of iodine in the manufactured resin particulates and higher degrees of uniformity of iodine content when comparing particulate to particulate.

Abstract: A method for the preparation of a modified fluoropolymer powdered material is disclosed. A suspension of solid fluoropolymer particles together with PTFE particles in an aqueous carrier, is frozen and the frozen carrier is then removed by sublimation at sub-atmospheric pressure to produce a dry powder of modified fluoropolymer particles.

Abstract: A method for the preparation of hydrophilic elastomers involves the synthesis of polydimethylsiloxane with tunable hydrophilic surface properties. An elastomeric monolith with desired hydrophilic properties is produced by combining a polyethylene oxide polymeric surfactant additive with a PDMS base and curing agent during polymerization. The surfactant chain segment lengths are varied to control the hydrophobic/hydrophilic balance.

Abstract: The present case relates to a process for the purification of lactide from a crude lactide vapor product stream which process comprises a rectification/condensation step leading to a lactide-enriched condensate.

Abstract: A process for producing non-solid-stated polyester polymer particles having one or more properties similar to polyester polymer particles that have undergone solid-state processing. In one embodiment, the process comprises (a) forming polyester polymer particles from a polyester polymer melt; (b) quenching at least a portion of the particles, (c) drying at least a portion of the particles, (d) crystallizing at least a portion of the particles, (e) annealing at least a portion of the particles. At all points during and between steps (b) through (e), the average bulk temperature of the particles is maintained above 165° C.

Abstract: The present invention relates to a polycarbonate resin composition which comprises a polycarbonate resin having the repeating unit that is represented by the following general formula (1) and a hydroxyl group at terminal thereof and has the concentration of the terminal hydroxyl group of 1000 ppm or more.

Abstract: Spheroidal polyester polymer particles, as well as preforms and stretch blow molded bottles made from the spheroidal particles, are provided which have: A) an It.V. of at least 0.72 dL/g, and either B) at least two melting peaks (on a DSC first heating scan), wherein one of said at least two melting peaks is a low peak melting point having a peak temperature within a range of 140° C. to 220° C.

Abstract: Processes for making polyesters in a polyester production facility are disclosed, that include the steps of forming a reaction medium comprising at least one monomer that includes terephthalic acid (TPA) and/or an ester derivative of TPA; subjecting at least a portion of the reaction medium to one or more chemical reactions in the polymer production facility to thereby produce the polyester; and heating the reaction medium at one or more locations in the polyester production facility, wherein at least 50 percent of the total energy input employed for the heating of the reaction medium is provided by indirect heat exchange between the reaction medium and steam.

Abstract: The method for producing a sulfonic acid group-containing carbonaceous material of the present invention comprises the step of carbonizing and sulfonating a polymer having a structural unit derived from resorcinol by heating in an inert gas atmosphere to obtain a sulfonic acid group-containing carbonaceous material. A catalyst comprising the resulting sulfonic acid group-containing carbonaceous material is useful for producing a target substance with high efficiency in various reactions in hydrophobic media such as alkylation reaction and polymerization reaction of olefins.

Abstract: A method for producing polycrystalline silicon, including: reacting trichlorosilane and hydrogen to produce silicon and a remainder including monosilanes (formula: SiHnCl4-n, wherein n is 0 to 4) containing silicon tetrachloride, and a polymer including at least trisilanes or tetrasilanes; and supplying the remainder and hydrogen to a conversion reactor and heating at a temperature within the range of 600 to 1,400° C. to convert silicon tetrachloride into trichlorosilane and the polymer into monosilanes.

Abstract: Processes for making polyesters in a polyester production facility are disclosed, that include the steps of: forming a reaction medium comprising at least one monomer that includes terephthalic acid (TPA) and/or an ester derivative of TPA; subjecting at least a portion of the reaction medium to one or more chemical reactions in the polyester production facility to thereby produce the polyester; generating high-pressure steam having a pressure of at least 5 megapascals; heating one or more process fluid streams of the polyester production facility by indirect heat exchange with the high-pressure steam, wherein the process fluid streams include any stream that is formed predominately of the reaction medium and/or the at least one monomer; heating a heat transfer medium (HTM) via indirect heat exchange with the high-pressure steam to thereby form heated HTM; and heating at least a portion of the process fluid streams by indirect heat exchange with the heated HTM.

Abstract: A silicone resin containing boron, aluminum, and/or titanium, and having silicon-bonded branched alkoxy groups; a silicone composition containing a silicone resin; and a method of preparing a coated substrate comprising applying a silicone composition on a substrate to form a film and pyrolyzing the silicone resin of the film.

Abstract: A fluororubber composition including a polyol-crosslinkable fluororubber; a cross-linking accelerator comprising a quaternary ammonium salt; and a polyol crosslinking agent; wherein the weight ratio X (quaternary ammonium salt/polyol crosslinking agent) between the cross-linking accelerator and the polyol crosslinking agent is in a range of 0.40 to 0.60; and a production method of a cross-linked fluororubber product, comprising the steps of: previously polyol-crosslinking, as required, the fluororubber composition; and subsequently heat treating the polyol-crosslinked composition, in a temperature range of 200° C. to 300° C. for 0.1 to 48 hours. The fluororubber composition has surface has a lower friction coefficient, and the surface roughness of the cross-linked fluororubber product can be increased without applying a treatment to a mold.

Abstract: In various aspects provided are methods for producing a nanoparticle within a cross-linked, collapsed polymeric material, said method including (a) providing a polymeric solution comprising a polymeric material; (b) collapsing at least a portion of the polymeric material about one or more precursor moieties; (c) cross-linking the polymeric material; (d) modifying at least a portion of said precursor moieties to form one or more nanoparticles and thereby forming a composite nanoparticle. In various embodiments, a non-confined nanoparticle can be produced by complete pyrolysis of the confined nanoparticle, and a carbon-coated nanoparticle by incomplete pyrolysis of the confined nanoparticle.

Abstract: The present invention provides an apparatus for recovering a polymer from polymer solution, and a method of recovering a polymer using the apparatus. The apparatus includes a polymer solution-storage tank for storing a polymer solution; a polymer solution feeding pump for pumping the polymer solution from the polymer solution storage tank; an antisolvent storage tank for storing an antisolvent; an antisolvent feeding pump for pumping the antisolvent from the antisolvent storage tank; a reaction chamber to which the polymer solution pumped by the polymer solution feeding pump and the antisolvent pumped by the antisolvent feeding pump are supplied; a high-speed mixer that is rotated in the reaction chamber at a speed range of 1000 to 30000 rpm, mixes the polymer solution with the antisolvent under a shearing force corresponding to a tip speed of 5 to 30 m/sec, and precipitates a polymer; and a precipitate storage tank for storing the precipitation mixture of the polymer and the solvent/antisolvent.

Abstract: The invention relates to a method for recycling polyesters or polyester mixtures from polyester-containing waste, in which the polyester or the polyester mixture is dissolved in a solvent and subsequently free-flowing particles are precipitated herefrom with a precipitant. The precipitant is thereby chosen such that subsequent separation of precipitant and solvent is made possible in a simple manner.

Abstract: The invention relates to a process for making modified polybutylene terephthalate random copolymers from a polyethylene terephthalate component. In one embodiment, the invention relates to a two step process in which a 1,4-butane diol component reacts with a polyethylene terephthalate component under conditions that depolymerize the polyethylene terephthalate component into a molten mixture and the molten mixture is placed under subatmospheric conditions that produce the modified polybutylene terephthalate random copolymers.

Abstract: A process for continuously producing a thermoplastic copolymer, in which a copolymer (A) containing unsaturated carboxylic acid alkyl ester units and unsaturated carboxylic acid units is produced and in succession heat-treated to perform intramolecular cyclization reaction by dehydration and/or dealcoholization reaction, for producing a thermoplastic copolymer (B) containing glutaric anhydride units and the unsaturated carboxylic acid alkyl ester units. The obtained copolymer is excellent in heat resistance and colorless transparency and very small in foreign matter content.

Abstract: A process for producing non-solid-stated polyester polymer particles having one or more properties similar to polyester polymer particles that have undergone solid-state processing. In one embodiment, the process comprises (a) forming polyester polymer particles from a polyester polymer melt; (b) quenching at least a portion of the particles, (c) drying at least a portion of the particles, (d) crystallizing at least a portion of the particles, (e) annealing at least a portion of the particles. At all points during and between steps (b) through (e), the average bulk temperature of the particles is maintained above 165° C.

Abstract: A separation object including at least two types of resins with different glass transition temperatures (glass transition temperature of a first resin 1<glass transition temperature of a second resin 2) is placed on a separating member 3. Next, primary heating is applied at a temperature between the glass transition temperatures of the first resin 1 and the second resin 2, and pressurization is additionally performed to cause the first resin 1 to adhere to the separating member 3. Subsequently, a heat history of secondary heating at a temperature higher than the primary heating temperature is applied to detach and recover the second resin 2 by restoring the shape of the second resin 2, while the first resin 1 adhering to and retained by the separating member 3 is detached by a blade 5 and the like for recovery.

Abstract: In the production of elastomers the product obtained from the polymerization process is often in the form of a slurry. Described herein are an apparatus and a process for “finishing” the elastomer, i.e., dewatering and drying the elastomer. The process comprises the steps of obtaining a slurry comprising water and elastomer; passing the slurry through a first dewatering device to produce a wet elastomer crumb, wherein the first dewatering device comprises two dewatering extruders in parallel; passing the wet elastomer crumb through a second dewatering device; and then passing the wet elastomer crumb through a drying device to produce a dried elastomer crumb.

Abstract: The invention relates to polyacetal compositions comprising a mixture of (i) a polyacetal resin, (ii) p-aramid particles and (III) a vinyl-terminated dimethyl siloxane polymer. These compositions are useful in preparing molded articles exhibiting a good balance between high self-lubricating properties and wear resistance, and especially useful in articles that are in motion with respect to other parts they are in contact with.

Abstract: Methods and systems for processing waste materials and for manufacturing composite materials are disclosed herein. According to some embodiments, the heterogeneous waste includes a plastic component and a non-plastic component, and the non-plastic component includes a plurality of pieces of waste. The heterogeneous waste is heated to melt at least a portion of said plastic component and reducing a volume of said heterogeneous waste, and then mixed (e.g. by rotating a mixing chamber or by stirring) until at least some said pieces are each encapsulated by the melted plastic component. Upon cooling, the mixture optionally sets into a composite material. The presently disclosed invention does not require pre-sorting of the heterogeneous waste and is operative to process “as is” waste. Optionally, the waste is pre-sorted.

Abstract: In the production of elastomers the product obtained from the polymerization process is often in the form of a slurry. Described herein are an apparatus and a process for “finishing” the elastomer, i.e., dewatering and drying the elastomer. The process comprises the steps of obtaining a slurry comprising water and elastomer; passing the slurry through a first dewatering device to produce a wet elastomer crumb, wherein the first dewatering device comprises two dewatering extruders in parallel; passing the wet elastomer crumb through a second dewatering device; and then passing the wet elastomer crumb through a drying device to produce a dried elastomer crumb.

Abstract: A method for treating an unstretched thermoplastic resin film. The method includes includes heat treating an unstretched thermoplastic resin film at a glass transition temperature of the thermoplastic resin Tg° C. or higher and Tg+50° C. or lower for 10 seconds or longer and 600 seconds or shorter while conveying the thermoplastic resin film at a tension of 2 N/cm2 or higher and 50 N/cm2 or lower. The method provides a thermoplastic resin film has an in-plane retardation (Re) and a retardation in the thickness direction (Rth) close to 0 nm, and as such the thermoplastic resin film after heat treatment has |Re| of 0 to 10 nm and |Rth| of 0 to 20 nm.