Polyimide film having excellent heat resistance and mechanical properties and method for manufacturing same

Abstract

The present invention provides a polyimide film comprising a copolymer in which an acid dianhydride monomer containing pyromellitic dianhydride (PMDA) is copolymerized with a diamine monomer containing 4,4'-diaminodiphenyl ether (ODA) and m-tolidine (m-TD), wherein the thermal expansion coefficient CTETD in the transverse direction (TD) of the film, measured under conditions of a temperature range of 50-200°C and a heating rate of 10°C / min, is -5 to 2.5ppm / °C, and the modulus thereof is 8GPa or more.

Description

Polyimide film with excellent heat resistance and mechanical properties and method for manufacturing the same

[0001] The present invention relates to a polyimide film having excellent heat resistance and mechanical properties and a method for producing the same. More specifically, the present invention relates to a polyimide film having excellent heat resistance and mechanical properties without using p-phenylenediamine (PPD), and a method for producing the same.

[0002] Polyimide (PI) is a polymer material that has the highest level of heat resistance, chemical resistance, electrical insulation, chemical resistance, and weather resistance among organic materials, based on an imide ring with excellent chemical stability and a rigid aromatic main chain.

[0003] In general, polyimide (PI) film is a film made of polyimide resin. Polyimide resin is a high-heat-resistant resin manufactured by solution polymerizing aromatic dianhydride and aromatic diamine or aromatic diisocyanate to produce a polyamic acid derivative, and then imidizing it by ring-closing dehydration at high temperatures.

[0004] Conventional polyimide resins primarily use paraphenylenediamine (p-phenylenediamine, PPD) as an aromatic diamine. However, PPD can cause bubbles and gel formation during film manufacturing, resulting in low productivity and process efficiency. Furthermore, when a low coefficient of thermal expansion is required, large amounts of PPD are used, resulting in poor chemical resistance.

[0005] Accordingly, there is a need to develop a polyimide film with excellent heat resistance and mechanical properties after imidization without using paraphenylenediamine.

[0006] The purpose of the present invention is to provide a polyimide film having excellent heat resistance and mechanical properties after imidization without using paraphenylenediamine (p-phenylenediamine, PPD), and a method for manufacturing the same.

[0007] In addition, the present invention aims to provide a display device including the polyimide film.

[0008] The present invention is susceptible to various modifications and embodiments. Therefore, specific embodiments are illustrated and described in detail. However, this is not intended to limit the present invention to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention.

[0009] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the terms "comprise" or "have" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0010] When amounts, concentrations, or other values ​​or parameters are given herein as a range, preferred range, or enumeration of an upper preferred value and a lower preferred value, it should be understood that this specifically discloses any range formed by any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed.

[0011] When a range of numerical values ​​is mentioned in this specification, unless otherwise stated, it is intended that the endpoints of the range and the scope of the invention within the range are not limited to the specific values ​​mentioned in defining the range.

[0012] As used herein, "dianhydride" is intended to include precursors or derivatives thereof, also referred to as "dianhydric acids," "dianhydrides," or "acid dianhydrides." While these may not technically be dianhydrides, they will nonetheless react with diamines to form polyamic acids, which can then be converted to polyimides.

[0013] As used herein, "diamine" is intended to include precursors or derivatives thereof, which may not technically be diamines, but which will nonetheless react with a dianhydride acid to form a polyamic acid, which in turn can be converted to a polyimide.

[0014] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and shall not be construed in an idealized or overly formal sense unless explicitly defined herein. Specific details for implementing the invention are described below.

[0015] The present invention relates to a polyimide film having excellent heat resistance and mechanical properties and a method for manufacturing the same.

[0016] polyimide film

[0017] The present invention comprises a copolymer in which a dianhydride monomer including pyromellitic dianhydride (PMDA) is copolymerized with a diamine monomer including 4,4'-diaminodiphenyl ether (ODA) and m-tolidine (m-TD), and the transverse direction (TD) thermal expansion coefficient CTE of the film is measured under the conditions of a measurement temperature range of 50 to 200°C and a heating rate of 10°C / min. TD A polyimide film having a viscosity of -5 to 2.5 ppm / ℃ and a modulus of 8 GPa or more is provided.

[0018] Specifically, the transverse direction (TD) thermal expansion coefficient CTE of the polyimide film measured under the conditions of a measurement temperature range of 50 to 200°C and a heating rate of 10°C / min. TD It may be -5 to 2.5 ppm / ℃, preferably -4.5 to 1.5 ppm / ℃.

[0019] Specifically, the polyimide film may have a modulus of 8 GPa or more. For example, the lower limit of the modulus may be 9 GPa or more, 9.5 GPa or more, or 10 GPa or more. In addition, the upper limit of the modulus is not particularly limited, but may be 18 GPa or less, 17 GPa or less, 16 GPa or less, or 15 GPa or less. The modulus was measured at a speed of 20 mm / min using an Instron 5564 UTM device manufactured by INSTRON, using a sample with a length of 80 mm and a width of 15 mm, and the average of 10 samples was calculated.

[0020] The above polyimide film has a coefficient of thermal expansion CTE in the machine direction (MD) MD and coefficient of thermal expansion CTE in the transverse direction (TD) TD The difference between (CTE) MD -CTE TD ) may be -3 to 3 ppm / ℃, preferably -2 to 2 ppm / ℃, more preferably -1.8 to 1.8 ppm / ℃.

[0021] The above polyimide film has an average coefficient of thermal expansion CTE Ave The average coefficient of thermal expansion CTE may be from -4.25 to 3.0 ppm / ℃, preferably from -4.35 to 2.0 ppm / ℃. Ave is the coefficient of thermal expansion CTE of the polyimide film in the machine direction (MD). MD and coefficient of thermal expansion CTE in the transverse direction (TD) TD It may be calculated as the average value.

[0022] Coefficient of thermal expansion CTE in the machine direction (MD) MD and coefficient of thermal expansion CTE in the transverse direction (TD) TD Each was measured at a slope of 50 to 200 ℃ at 10 ℃ / min and 50 mN using TA TMA equipment (Q400).

[0023] The above polyimide film may have a glass transition temperature (Tg) of 380°C or higher. For example, the lower limit of the glass transition temperature may be 385°C or higher, 395°C or higher, or 398°C or higher. In addition, the upper limit of the glass transition temperature is not particularly limited, but may be 500°C or lower, 495°C or lower, or 490°C or lower. The above glass transition temperature is measured using DMA at 10°C / min.

[0024] The above polyimide film may have a chemical resistance based on thickness of -25 to -13%, preferably -24.5 to -13.5%.

[0025] In one embodiment, the polyimide film may have a chemical resistance of -25 to -10% by weight, preferably -23.5 to -11%.

[0026] The above thickness-based chemical resistance and weight-based chemical resistance were each measured based on ASTM D570 absorption rate. The solution impregnation and storage standards were measured by checking the weight and thickness changes after immersion in a 15% NaOH solution at 60°C for 30 minutes and storage.

[0027] The above polyimide film may have a coefficient of hygroscopic expansion (CHE) of 3 to 6 ppm / RH%, preferably 3.5 to 5 ppm / RH%. The coefficient of hygroscopic expansion was measured using a PMIC device by performing stabilization under humidity conditions of 3 to 90% RH until no dimensional change occurred.

[0028] The thickness of the above polyimide film can be appropriately selected considering the purpose, usage environment, physical properties, etc. of the polyimide film. For example, the thickness of the polyimide film can be 1 to 100 μm, 15 to 70 μm, 25 to 50 μm, or 30 to 45 μm, but is not limited thereto.

[0029] Another embodiment of the present invention provides a multilayer film comprising the polyimide film and a thermoplastic resin layer.

[0030] Another embodiment of the present invention provides a flexible metal foil laminate comprising the polyimide film and an electrically conductive metal foil.

[0031] Another embodiment of the present invention provides an electronic component including the flexible metal foil laminated plate.

[0032] Another embodiment of the present invention provides a display device including the polyimide film.

[0033] copolymer

[0034] The above copolymer is a copolymer of a dianhydride monomer including pyromellitic dianhydride (PMDA) and a diamine monomer including 4,4'-diaminodiphenyl ether (ODA) and m-tolidine (m-TD).

[0035] The above copolymer may be a block copolymer having two or more blocks.

[0036] The above block copolymer may be composed of a first block copolymerized with a dianhydride monomer composed of pyromellitic dianhydride (PMDA) and a diamine monomer composed of m-tolidine (m-TD); and a second block copolymerized with a dianhydride monomer composed of pyromellitic dianhydride (PMDA) and a diamine monomer composed of 4,4'-diaminodiphenyl ether (ODA).

[0037] The m-tolidine (m-TD) content among the total diamine monomers of the copolymer may be 40 to 80 mol%, preferably 45 to 75 mol%, more preferably 50 to 70 mol%, and even more preferably 55 to 65 mol%. When the m-tolidine content is less than 40 mol%, the low hygroscopicity and low dielectric properties of the polyimide film are poor and the chemical resistance is very low, which is not preferable. When it exceeds 80 mol%, it is not preferable because it is difficult to form a polyimide film thereafter.

[0038] Among the total diamine monomers of the copolymer, the content of 4,4'-diaminodiphenyl ether (ODA) may be 20 to 60 mol%, preferably 25 to 55 mol%, more preferably 30 to 50 mol%, and even more preferably 35 to 45 mol%. If the content of 4,4'-diaminodiphenyl ether is less than 20 mol%, it is difficult to form a polyimide film thereafter, which is undesirable, and if it exceeds 60 mol%, the low hygroscopicity and low dielectric properties caused by including m-tolidine are insignificant, which is undesirable.

[0039] The molar ratio of the above-mentioned dihydric acid monomer and the above-mentioned diamine monomer may be 1:2 to 2:1, and preferably 1:1.

[0040] The above copolymer may contain 90 to 110 mol% of the diamine monomer, preferably 95 to 105 mol%, more preferably 98 to 102 mol%, and even more preferably 99 to 101 mol%.

[0041] The above copolymer may contain 90 to 110 mol% of the above dianhydride monomer, preferably 95 to 105 mol%, more preferably 98 to 102 mol%, and even more preferably 100 mol%.

[0042] The copolymer may contain 95 to 105 mol% of the dianhydride monomer based on 100 mol% of the diamine monomer, and for example, the lower limit may be 95.5 mol% or more, 96 mol% or more, 96.5 mol% or more, 97 mol% or more, 97.5 mol% or more, 98 mol% or more, 98.5 mol% or more, 99 mol% or more, or 99.5 mol% or more, and the upper limit may be 105 mol% or less, 104 mol% or less, 103 mol% or less, 102 mol% or less, 101 mol% or less, or 100 mol% or less.

[0043] Method for manufacturing polyimide film

[0044] The present invention relates to a method for producing a polyimide film, comprising a step of copolymerizing a dianhydride monomer containing pyromellitic dianhydride (PMDA) and a diamine monomer containing 4,4'-diaminodiphenyl ether (ODA) and m-tolidine (m-TD), wherein the transverse direction (TD) thermal expansion coefficient CTE of the polyimide film is measured under conditions of a measurement temperature range of 50 to 200°C and a heating rate of 10°C / min. TD A method for manufacturing a polyimide film is provided, wherein the polyimide film has a viscosity of -5 to 2.5 ppm / ℃ and a modulus of 8 GPa or more.

[0045] Specifically, the transverse direction (TD) thermal expansion coefficient CTE of the polyimide film measured under the conditions of a measurement temperature range of 50 to 200°C and a heating rate of 10°C / min. TD It may be -5 to 2.5 ppm / ℃, preferably -4.5 to 1.5 ppm / ℃.

[0046] Specifically, the polyimide film may have a modulus of 8 GPa or more. For example, the lower limit of the modulus may be 9 GPa or more, 9.5 GPa or more, or 10 GPa or more. In addition, the upper limit of the modulus is not particularly limited, but may be 18 GPa or less, 17 GPa or less, 16 GPa or less, or 15 GPa or less. The modulus was measured at a speed of 20 mm / min using an Instron 5564 UTM device manufactured by INSTRON, using a sample with a length of 80 mm and a width of 15 mm, and the average of 10 samples was calculated.

[0047] The above copolymerization step may include a step of polymerizing a dianhydride monomer including pyromellitic dianhydride (PMDA) and a diamine monomer including m-tolidine (m-TD) to produce a first block; and a step of polymerizing a dianhydride monomer including pyromellitic dianhydride (PMDA) and a diamine monomer including 4,4'-diaminodiphenyl ether (ODA) to produce a second block.

[0048] In the step of generating the first block, the content of the diamine monomer including the m-tolidine (m-TD) may be greater than the content of the dianhydride monomer including the pyromellitic dianhydride (PMDA).

[0049] Specifically, in the step of generating the first block, the content of the diamine monomer including the m-tolidine (m-TD) is 40 to 80 mol%, the content of the dianhydride monomer including the pyromellitic dianhydride (PMDA) is 20 to 70 mol%, and the content of the dianhydride monomer including the pyromellitic dianhydride (PMDA) (M 1st PMDA ) content of diamine monomer containing m-tolidine (m-TD) compared to the above m-TD ) ratio (M m-TD / M 1st PMDA ) may be greater than 1 and less than 2.

[0050] The above ratio (M m-TD / M 1st PMDA ) is less than 1 or more than 2, it is difficult to form a block copolymer of the target shape, which is not desirable.

[0051] In the step of generating the second block, the content of the diamine monomer including the 4,4'-diaminodiphenyl ether (ODA) may be less than the content of the dianhydride monomer including the pyromellitic dianhydride (PMDA).

[0052] Specifically, in the step of generating the second block, the content of the diamine monomer including the 4,4'-diaminodiphenyl ether (ODA) is 20 to 60 mol%, the content of the dianhydride monomer including the pyromellitic dianhydride (PMDA) is 30 to 80 mol%, and the content of the dianhydride monomer including the pyromellitic dianhydride (PMDA) (M 2nd PMDA ) compared to the content (M) of the diamine monomer containing the above 4,4'-diaminodiphenyl ether (ODA) ODA ) ratio (M ODA / M 2nd PMDA ) can be greater than 0 and less than 1.

[0053] The above ratio (M ODA / M 2nd PMDA) is 0 or 1 or more, it is difficult to form a block copolymer of the target shape, which is not desirable.

[0054] Each of the first block and the second block can be produced in the presence of a solvent.

[0055] The above solvent may include at least one selected from the group consisting of N,N'-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), N,N'-dimethylformamide (DMF), dimethylsulfoxide (DMSO), diethylacitamide (DEAc), N-ethyl-2-pyrrolidone (NEP), N,N'-diethylformamide (DEF), dimethylpropanamide (DMPA), and gamma-butyrolactone (GBL), and preferably, N,N'-dimethylformamide (DMF) may be used.

[0056] Another embodiment of the present invention provides a multilayer film comprising a polyimide film manufactured by the method for manufacturing the polyimide film and a thermoplastic resin layer.

[0057] Another embodiment of the present invention provides a flexible metal foil laminate comprising a polyimide film manufactured by the method for manufacturing the polyimide film and an electrically conductive metal foil.

[0058] Another embodiment of the present invention provides an electronic component including the flexible metal foil laminated plate.

[0059] Another embodiment of the present invention provides a display device including the polyimide film.

[0060] The polyimide film and its manufacturing method according to the present invention are relatively price competitive because they do not use paraphenylenediamine (p-phenylenediamine, PPD), and have excellent productivity and process efficiency.

[0061] In addition, the polyimide film according to the present invention has excellent heat resistance and mechanical properties.

[0062] In addition, the polyimide film according to the present invention has an effect that can be applied to display devices.

[0063] To aid in understanding the present invention, examples are presented. The following examples are provided solely to facilitate a better understanding of the present invention, and the scope of the present invention is not limited by the examples.

[0064] <Example>

[0065] Example 1. Preparation of polyimide film

[0066] Example 1-1

[0067] A solution containing the first block (m-TD / PMDA block) was prepared by mixing and polymerizing 80 mol% of a diamine monomer, m-tolidine (m-TD), and 60 mol% of a dianhydride monomer, pyromellitic dianhydride (PMDA), in 100 mol% of dimethylformamide (DMF).

[0068] In the above solution, 20 mol% of 4,4'-diaminodiphenyl ether (ODA), a diamine monomer, and 37 mol% of pyromellitic dianhydride (PMDA), a dianhydride monomer, were mixed and polymerized to form a second block (ODA / PMDA block).

[0069] Finally, 3 mol% of PMDA was additionally added to manufacture a polyamic acid including the first block (m-TD / PMDA block) and the second block (ODA / PMDA block).

[0070] The polyamic acid was mixed with a catalyst, and the resulting mixture was applied to a glass plate. The resulting polyamic acid was then spread evenly across the surface using an applicator, calculated from the solvent and solids ratio. The resulting polyamic acid was then cured under a nitrogen atmosphere at 130°C (4 minutes) → 280°C (4 minutes) → 420°C (4 minutes) to obtain a polyimide film. The film had a thickness of 33.5 μm.

[0071] Examples 1-2 to 1-6

[0072] A polyimide film was manufactured in the same manner as in Example 1-1, except that the content ratios of m-tolidine, ODA, and PMDA were adjusted as shown in Table 1 below.

[0073] Comparative Example 1-1

[0074] A polyimide film was manufactured in the same manner as in Example 1-1, except that the content ratios of m-tolidine, ODA, and PMDA were adjusted as shown in Table 1 below.

[0075] Comparative Example 1-2

[0076] A random copolymerized polyimide film was manufactured by mixing 50 mol% of m-tolidine (m-TD), 50 mol% of 4,4'-diaminodiphenyl ether (ODA), and 97 mol% of pyromellitic dianhydride (PMDA), which is an dianhydride compound, with 100 mol% of dimethylformamide (DMF), and then adding 3 mol% of PMDA.

[0077]

[0078] Table 1 below shows the composition and content of the dianhydride monomer and diamine monomer used in manufacturing the polyimide film according to Examples 1-1 to 1-6 and Comparative Example 1-1.

[0079] m-TD (mol%)1st PMDA (mol%)ODA (mol%)2nd PMDA (mol%)3rd PMDA (mol%)Copolymer typeExample 1-1806020373BlockExample 1-27052.53044.53BlockExample 1-36045.04052.03BlockExample 1-46548.83548.23BlockExample 1-55037.55059.53BlockExample 1-64030.06067.03BlockComparative Example 1-13022.57074.53Block

[0080]

[0081] Table 2 below shows the composition and content of the dianhydride monomer and diamine monomer used in manufacturing the polyimide film according to Comparative Example 1-2.

[0082] m-TD (mol%)ODA (mol%)Primary PMDA (mol%)Secondary PMDA (mol%)Copolymer Type Comparison Example 1-25050973Random

[0083]

[0084] <Experimental Example>

[0085] Experimental Example 1. Evaluation of the physical properties of polyimide films

[0086] (1) Coefficient of thermal expansion (CTE)

[0087] For the polyimide films of Examples 1-1 to 1-6 and Comparative Examples 1-1 and 1-2, the slope was measured in the range of 50 to 200°C under the conditions of 10°C / min and 50 mN in the machine direction (MD) and the transverse direction (TD) using a TA TMA device (Q400). Thereafter, the coefficient of thermal expansion CTE in the machine direction (MD) was measured. MD and coefficient of thermal expansion CTE in the transverse direction (TD) TD Average coefficient of thermal expansion CTE from values Ave Wow, MD coefficient of thermal expansion CTE MD and TD coefficient of thermal expansion CTE TD The difference value (CTE) MD -CTE TD ) was calculated. The coefficient of thermal expansion (CTE) in the machine direction (MD) of the polyimide film MD , transverse direction (TD) coefficient of thermal expansion CTE TD , average coefficient of thermal expansion CTE Ave and MD coefficient of thermal expansion CTE MD and TD coefficient of thermal expansion CTE TD The difference value (CTE) MD -CTE TD ) The results of each measurement are shown in Table 3 below.

[0088] (2) Glass transition temperature (Tg)

[0089] The glass transition temperature of the polyimide films of Examples 1-1 to 1-6 and Comparative Examples 1-1 and 1-2 was measured using DMA at 10°C / min. The results are shown in Table 3 below.

[0090] (3) Modulus

[0091] For the polyimide films of Examples 1-1 to 1-6 and Comparative Examples 1-1 and 1-2, samples measuring 80 mm in length and 15 mm in width were prepared using an Instron 5564 UTM device from INSTRON, and measurements were made at a speed of 20 mm / min, and the average of 10 samples was calculated. The results are shown in Table 3 below.

[0092] (4) Chemical resistance

[0093] Thickness-based chemical resistance and weight-based chemical resistance were measured for the polyimide films of Examples 1-1 to 1-6 and Comparative Examples 1-1 and 1-2, respectively, and the results are shown in Table 3 below.

[0094] The above thickness-based chemical resistance and weight-based chemical resistance were each measured based on ASTM D570 absorption rate. The solution impregnation and storage standards were measured by checking the weight and thickness changes after immersion in a 15% NaOH solution at 60°C for 30 minutes and storage.

[0095] (5) Coefficient of hygroscopic expansion (CHE)

[0096] For the polyimide films of Examples 1-2, 1-3, and 1-5 and Comparative Examples 1-1 and 1-2, the coefficient of hygroscopic expansion was measured by stabilizing them under humidity conditions of 3 to 90% RH using PMIC equipment until no dimensional changes occurred. The results are shown in Table 3 below.

[0097]

[0098] Table 3 below summarizes the results of property evaluation of the polyimide films of Examples 1-1 to 1-6 and Comparative Examples 1-1 and 1-2.

[0099] Classification CTE (ppm / ℃) Tg (℃) Modulus (GPa) Chemical resistance (%) CHE (ppm / RH%) MDTD Average difference Thickness Weight Example 1-1-3.07-4.50-3.79 1.43 412 12.9-14.5-13.3-Example 1-2-3.19-3.55-3.37 0.36 413 11.8-13.9-11.8 4.0 Example 1-3-1.55-1.78-1.67 0.23 406 10.3-16.2-13.9 4.4 Example 1-4-3.03-2.40-2.72-0.63 409 12.6-14.4-14.4-Example 1-5-0.30-0.73-0.50.434029.8-18.9-20.15.7Example 1-63.82.02.91.84028.1-25.0-24.6Comparative Example 1-19.44.87.14.64006.2-32.1-34.27.2Comparative Example 1-23.13.43.2-0.34008.8-34.0-32.96.7

[0100]

[0101] According to Table 3, when including a block copolymer, the example having an m-TD content of 40 to 80 mol% has better chemical resistance than the comparative example 1-1 having an m-TD content of 30 mol%, and it can be confirmed that the CTE and CHE are also better.

[0102] In addition, when comparing the physical properties according to the inclusion of blocks in the same content (Example 1-5 and Comparative Example 1-2), it can be confirmed that other physical properties are similar, but when blocks are included, heat resistance and chemical resistance are significantly superior.

[0103] From these results, it can be confirmed that the polyamic acid of the present invention and the polyimide film manufactured therefrom have excellent heat resistance, chemical resistance, moisture resistance, and mechanical properties without using paraphenylenediamine (p-phenylenediamine, PPD).

[0104] In addition, since the polyimide film of the present invention does not use paraphenylenediamine (p-phenylenediamine, PPD), it has relatively high price competitiveness and excellent productivity and process efficiency.

[0105]

[0106] The specification omits detailed descriptions of matters that would be readily apparent and inferred by those skilled in the art. Furthermore, various modifications, other than the specific examples described herein, are possible without altering the technical spirit or essential configuration of the invention. Therefore, the present invention may be practiced in ways other than those specifically described and exemplified herein, as will be readily apparent to those skilled in the art.

Claims

1. A copolymer comprising a dianhydride monomer including pyromellitic dianhydride (PMDA) and a diamine monomer including 4,4'-diaminodiphenyl ether (ODA) and m-tolidine (m-TD), The coefficient of thermal expansion CTE of the film in the transverse direction (TD) measured under the conditions of a measurement temperature range of 50 to 200°C and a heating rate of 10°C / min. TD is -5 to 2.5 ppm / ℃, Polyimide film having a modulus of 8 GPa or more.

2. In paragraph 1, Coefficient of thermal expansion CTE in the machine direction (MD) of the above polyimide film MD and transverse direction (TD) coefficient of thermal expansion CTE TD The difference between (CTE) MD -CTE TD ) is -3 to 3 ppm / ℃, polyimide film.

3. In paragraph 1, Average coefficient of thermal expansion CTE of the above polyimide film Ave is -4.25 to 3.0 ppm / ℃, The above average coefficient of thermal expansion CTE Ave is the coefficient of thermal expansion CTE in the machine direction (MD) of the polyimide film. MD and transverse direction (TD) coefficient of thermal expansion CTE TD Polyimide film, which is calculated by the average value of .

4. In paragraph 1, A polyimide film, wherein the copolymer is a block copolymer having two or more blocks.

5. In paragraph 4, The above block copolymer comprises a first block copolymerized with a dianhydride monomer composed of pyromellitic dianhydride (PMDA) and a diamine monomer composed of m-tolidine (m-TD); and A polyimide film comprising a second block copolymerized with a dianhydride monomer composed of pyromellitic dianhydride (PMDA) and a diamine monomer composed of 4,4'-diaminodiphenyl ether (ODA).

6. In paragraph 1, A polyimide film, wherein the m-tolidine (m-TD) content among the total diamine monomers of the copolymer is 40 to 80 mol%.

7. In paragraph 1, A polyimide film, wherein the content of 4,4'-diaminodiphenyl ether (ODA) among the total diamine monomers of the copolymer is 20 to 60 mol%.

8. In paragraph 1, A polyimide film having a glass transition temperature (Tg) of 380°C or higher.

9. In paragraph 1, A polyimide film having a chemical resistance based on thickness of -25 to -13% and a chemical resistance based on weight of -25 to -10%.

10. In paragraph 1, A polyimide film having a hygroscopic expansion coefficient of 3 to 6 ppm / RH%.

11. In paragraph 1, A polyimide film having a thickness of 1 to 100 μm.

12. A method for manufacturing a polyimide film, comprising a step of copolymerizing a dianhydride monomer containing pyromellitic dianhydride (PMDA) and a diamine monomer containing 4,4'-diaminodiphenyl ether (ODA) and m-tolidine (m-TD), The coefficient of thermal expansion CTE in the transverse direction (TD) of the polyimide film measured under the conditions of a measurement temperature range of 50 to 200°C and a heating rate of 10°C / min. TD is -5 to 2.5 ppm / ℃, A method for manufacturing a polyimide film, wherein the modulus of the polyimide film is 8 GPa or more.

13. In paragraph 12, The above copolymerization step A step of producing a first block by polymerizing a dianhydride monomer including pyromellitic dianhydride (PMDA) and a diamine monomer including m-tolidine (m-TD); and A method for producing a polyimide film, comprising the step of polymerizing a dianhydride monomer containing pyromellitic dianhydride (PMDA) and a diamine monomer containing 4,4'-diaminodiphenyl ether (ODA) to produce a second block.

14. In paragraph 13, In the step of generating the first block, The content of the diamine monomer including the above m-tolidine (m-TD) is 40 to 80 mol%, The content of the dianhydride monomer including the above pyromellitic dianhydride (PMDA) is 20 to 70 mol%, The content (M) of the dianhydride monomer containing the above pyromellitic dianhydride (PMDA) 1st PMDA ) content of diamine monomer containing m-tolidine (m-TD) compared to the above m-TD ) ratio (M m-TD / M 1st PMDA ) is greater than 1 and less than 2, a method for manufacturing a polyimide film.

15. In paragraph 13, In the step of generating the second block, The content of the diamine monomer including the above 4,4'-diaminodiphenyl ether (ODA) is 20 to 60 mol%, The content of the dianhydride monomer including the above pyromellitic dianhydride (PMDA) is 30 to 80 mol%, The content (M) of the dianhydride monomer containing the above pyromellitic dianhydride (PMDA) 2nd PMDA ) compared to the content (M) of the diamine monomer containing the above 4,4'-diaminodiphenyl ether (ODA) ODA ) ratio (M ODA / M 2nd PMDA ) is greater than 0 and less than 1, a method for manufacturing a polyimide film.