Black polyimide film and method for producing same

Abstract

Provided is a black polyimide film formed by imidizing a polyamic acid obtained from a dianhydride monomer and a diamine monomer, the black polyimide film including a black pigment containing bituminous coal and lactam black.

Description

Technical Field

[0001] The present invention relates to a black polyimide film and a method for manufacturing the same, and more particularly, to a low dielectric (low-k) black polyimide film including a black pigment and a method for manufacturing the same. Background Art

[0002] Polyimide is a general term for polymers having an imide structure, and is generally prepared by the condensation reaction of aromatic anhydrides and aromatic diamines, and has excellent properties such as high heat resistance (can withstand temperatures from extremely low temperatures to high temperatures exceeding 400°C), high electrical insulation, high radiation resistance, high chemical resistance, etc. Therefore, it is used as a high-tech material and insulating coating in a wide range of fields, such as in the fields of electrical and electronic products, semiconductors, displays, automobiles, aerospace, and space materials.

[0003] However, the use of polyimide has been limited due to its "insoluble or infusible" nature that it is insoluble in solvents and cannot be molded by heating. Therefore, most polyimides are manufactured by treating polyamic acid as a precursor, followed by high-temperature heat treatment and curing imidization processes, and a representative product manufactured in this manner is a polyimide film.

[0004] Recently, polyimide films are widely used as cover films for portable electronic devices and communication devices. Cover films are designed to protect electronic components (such as printed wiring boards and lead frames of semiconductor integrated circuits), and require physical properties such as thin film and thinness, and in recent years, cover films also require optical properties and safety, portability, visual effects and concealability of electronic components or mounted components.

[0005] Generally, both matting agents and colorants (e.g., pigments or dyes) are used in the manufacture of polyimide films. In conventional manufacturing methods, a colorant (such as carbon black) can be generally included to reduce the transparency of the polyimide film, and a matting agent (such as SiO2) can be added to reduce the glossiness of the polyimide film. However, neither a colorant nor a matting agent can achieve the reduction of matting properties and transparency alone. Therefore, conventional manufacturing methods need to use a large amount of colorants and matting agents to give the desired properties of the polyimide film, which may cause some problems (such as, not only difficult to handle and poor dispersion of additives, but also high dielectric constant and dielectric loss factor), making it difficult to internalize 5G electronic devices.

[0006] Therefore, there is a need to develop a black polyimide film for high-speed transmission, which includes an optimized black pigment and is capable of satisfying all of a low dielectric constant and a low dielectric loss factor as well as low gloss and low light transmittance without adding a matting agent. Summary of the invention

[0007] Technical issues

[0008] An object of the present invention is to provide a low dielectric (low-k) black polyimide film, which includes a black pigment with a controlled particle size in polyimide, has excellent optical properties (such as gloss, transmittance, etc.), and achieves a low dielectric constant and a low dielectric loss factor.

[0009] In addition, another object of the present invention is to provide a method for manufacturing a black polyimide film.

[0010] In addition, another object of the present invention is to provide a cover film including a black polyimide film.

[0011] In addition, another object of the present invention is to provide an electronic device for high-speed transmission including the cover film.

[0012] Technical Solution

[0013] Hereinafter, exemplary embodiments of the present invention will be described in more detail in the order of “black polyimide film” and “method of manufacturing black polyimide film” according to the present invention.

[0014] Since the present invention can be variously modified and has various exemplary embodiments, specific exemplary embodiments are described in detail. However, these are not intended to limit the present invention to specific exemplary embodiments, and should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

[0015] The terms used in the present invention are only used to describe specific exemplary embodiments and are not intended to limit the present invention. Unless the context clearly indicates otherwise, singular expressions include plural expressions. In this specification, terms such as "including", "having", etc. are intended to indicate the presence of features, quantities, steps, operations, components, parts, or combinations thereof described in the specification, and it should be understood that these terms do not exclude the possibility of the presence or addition of one or more other features, quantities, steps, operations, components, parts, or combinations thereof.

[0016] When amounts, concentrations or other values ​​or parameters in this specification are provided as ranges, preferred ranges or a list of upper preferred values ​​and lower preferred values, this will be understood to specifically disclose all ranges 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 disclosed individually.

[0017] Where numerical ranges are recited herein, it is not intended that the range be limited to the endpoints and that the scope of the invention be limited to the specific values ​​recited when defining a range unless otherwise indicated.

[0018] As used herein, the term "dianhydride" is intended to include its precursors or derivatives, also known as "dianhydride acid," "double anhydride," or "acid dianhydride." It may not technically be a dianhydride, but nonetheless will react with a diamine to form a polyamic acid that can be converted back into a polyimide.

[0019] "Diamine" herein is intended to include precursors or derivatives thereof which may not technically be diamines but which can still react with the dianhydride acid to form a polyamic acid which can be converted back to a polyimide.

[0020] Unless otherwise defined, all terms (including technical or scientific terms) used herein have the same meaning as those generally understood by those skilled in the art to which the embodiments belong. Terms (such as those defined in general dictionaries) should be interpreted as having a meaning consistent with the meaning in the context of the relevant field, and will not be interpreted in an idealized or overly formal sense unless clearly defined in the present invention. Specific details for implementing the invention will be described below.

[0021] Black polyimide film

[0022] The present invention provides a black polyimide film comprising a black pigment including bituminous coal and lactam black, wherein the black polyimide film is formed by imidizing a polyamic acid obtained from a dianhydride monomer and a diamine monomer.

[0023] Bituminous coal (also known as soft coal) is a black or dark black coal with a glassy or resinous luster and has a high content of volatile matter. In the present invention, the bituminous coal may contain up to 20% of volatile matter and about 75% of fixed carbon. In addition, the bituminous coal may contain up to 1% of moisture, up to 0.9% of SO2, and about 7.5% of ash. In the polyimide film of the present invention, by including bituminous coal, the glossiness can be reduced.

[0024] For example, the bituminous coal may be Mineral Black 325BA (Keystone Filley & Mfg.), Austin Black 325 (Coal Fillers), or a combination thereof, and embodiments of the present invention use Austin Black 325 manufactured by Coal Fillers.

[0025] The lactam black pigment, which is an infrared transmitting pigment, is one of black organic pigments that is made of an organic material and absorbs light in the visible wavelength range to appear black, and contains a lactam structure in the molecule.

[0026] Examples of lactam black may include BASF's Black 582 and Black S0100CF and SBPI-1 of SKC High-Tech & Marketing. In the embodiment of the present invention, SBPI-1 manufactured by SKC Hi-Tech & Marketing Co., Ltd. was used.

[0027] In the present invention, based on the gross weight of the film, the film may contain 5% to 30% of black pigment by weight. Preferably, the lower limit of the black pigment may be 5% or more by weight, 6% or more by weight, 7% or more by weight, 8% or more by weight, 9% or more by weight, 10% or more by weight, 11% or more by weight, 12% or more by weight, 13% or more by weight, or 14% or more by weight, and the upper limit of the black pigment may be 30% or less by weight, 29% or less by weight, 28% or less by weight, 27% or less by weight, 26% or less by weight, 25% or less by weight, 24% or less by weight, 23% or less by weight, 22% or less by weight, 21% or less by weight, 20% or less by weight, 19% or less by weight, 18% or less by weight, or 17% or less by weight. When the amount of the black pigment in the film is less than 5% by weight, light transmittance may increase, and when the amount is greater than 30% by weight, dispersibility and physical properties of the film may be poor.

[0028] In the present invention, based on the total weight of the film, the film may include 3% to 15% bituminous coal and 2% to 15% lactam black by weight. Preferably, based on the total weight of the film, the film may include 5% to 10% bituminous coal and 4% to 10% lactam black by weight. For example, the lower limit of bituminous coal may be 3% or more by weight, 3.5% or more by weight, 4% or more by weight, 4.5% or more by weight, 5% or more by weight, 5.5% or more by weight, 6% or more by weight, or 6.5% or more by weight, and the upper limit of bituminous coal may be 10% or less by weight, 9% or less by weight, 8% or less by weight, or 7% or less by weight. When using more than 15% bituminous coal by weight, the transmittance cannot be effectively reduced.

[0029] In addition, as an example, the lower limit amount of lactam black may be 2% by weight or more, 2.5% by weight or more, 3% by weight or more, 3.5% by weight or more, 4% by weight or more, 4.5% by weight or more, 5% by weight or more, 5.5% by weight or more, 6% by weight or more, 6.5% by weight or more, 7% by weight or more, or 7.5% by weight or more, and the upper limit amount of lactam black may be 10% by weight or less, 9.5% by weight or less, 9% by weight or less, 8.5% by weight or less, or 8% by weight or less.

[0030] In the present invention, by including a black pigment containing bituminous coal and lactam black, glossiness, light transmittance, dielectric constant, and dielectric loss factor can be maintained low.

[0031] In the present invention, the bituminous coal may have an average particle size (D50) of 0.5 μm to 10 μm, preferably, an average particle size (D50) of 1 μm to 8 μm, and more preferably, an average particle size (D50) of 2 μm to 5 μm. In addition, the bituminous coal may have an average particle size (D10) of 0.5 μm to 2 μm and an average particle size (D90) of 3 μm to 7 μm. The average particle size of the bituminous coal may represent the average particle size after grinding. When the average particle size (D50) exceeds 10 μm, the surface properties of the film may be impaired, the dispersibility may be reduced, or the mechanical properties of the film may be deteriorated.

[0032] In the present invention, lactam black can have an average particle size (D50) of 30nm to 1000nm, in particular, an average particle size (D50) of 40nm to 900nm, more particularly, an average particle size (D50) of 50nm to 500nm, still more particularly, an average particle size (D50) of 100nm to 300nm, and even more particularly, an average particle size (D50) of 100nm to 200nm. In addition, lactam black can have an average particle size (D10) of 100nm to 200nm and an average particle size (D90) of 100nm to 300nm. The average particle size of lactam black can represent the average particle size after grinding. When the average particle size (D50) exceeds 1000nm, the surface properties of the film will be impaired, the dispersibility will be reduced, or the mechanical properties of the film will deteriorate.

[0033] The present invention can realize a black polyimide film having low gloss, low transparency, low dielectric constant, and low dielectric loss factor by adjusting the particle size of the black pigment to an appropriate particle size through grinding.

[0034] In the present invention, the dianhydride monomer can be selected from pyromellitic dianhydride (PMDA), oxydiphthalic dianhydride (oxydiphthalic dianhydride, ODPA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (sBPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA), diphenyl sulfone-3,4,3',4'-tetracarboxylic dianhydride (DSDA), bis(3,4-dicarboxyphenyl) sulfide dianhydride, 2,2-bis(3,4-dicarboxyphenyl)-1,1,1,3,3,3-hexafluoropropane dianhydride, 2,3,3',4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA), bis(3,4-dicarboxyphenyl)methane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, p-phenylencbis(trimelliticmonoester acid) anhydride), at least one selected from the group consisting of p-biphenyl bis(trimellitic acid monoester anhydride), m-terphenyl-3,4,3',4'-tetracarboxylic dianhydride, p-terphenyl-3,4,3',4'-tetracarboxylic dianhydride, 1,3-bis(3,4-dicarboxyphenoxy)phthalic dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)phthalic dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)biphenyl dianhydride, 2,2-bis[(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (BPADA), 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride and 4,4'-(2,2-hexafluoroisopropylidene)diphthalic dianhydride, in particular, It may be at least one selected from the group consisting of pyromellitic dianhydride (PMDA), oxydiphthalic dianhydride (ODPA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (sBPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA) and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA), and more particularly, it may be at least one selected from the group consisting of pyromellitic dianhydride (PMDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (sBPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA) and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA).

[0035] In addition, the diamine monomer may be selected from p-phenylenediamine (PPD), m-phenylenediamine, 3,3'-dimethylbenzidine, 2,2'-dimethylbenzidine, 2,4-diaminotoluene, 2,6-diaminotoluene, 3,5-diaminobenzoic acid (DABA), 4,4'-oxydianiline (ODA), 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane (4,4'-methylenedianiline), 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine), 2,2'-bis(trifluoromethyl)-4 ,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-dicarboxy-4,4'-diaminodiphenylmethane, 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane, bis(4-aminophenyl) sulfide, 4,4'-diaminobenzanilide, 3,3'-dimethoxybenzidine, 2,2'-dimethoxybenzidine, 3,3'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 4,4'- Diaminodiphenyl sulfone, 3,3'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-diamino-4,4'-dichlorobenzophenone, 3,3'-diamino-4,4'-dimethoxybenzophenone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2-bis(3-aminophenyl)propane, 2,2-bis(4-aminophenyl)propane, 2,2-bis(3-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-bis(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 3,3'-diaminodiphenyl sulfoxide, 3,4'-diaminodiphenyl sulfoxide, 4,4'-diaminodiphenyl sulfoxide, 1,3-bis (3-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(3-aminophenyl)benzene, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenoxy)benzene (TPE-R), 1,4-bis(3-aminophenoxy)benzene (TPE-Q), 1,3-bis(3-aminophenoxy)-4-trifluoromethylbenzene, 3,3'-diamino-4-(4-phenylphenoxy)benzophenone, 3,3'-diamino-4,4'-bis(4-phenylphenoxy)benzophenone, 1,3-bis(3-aminophenyl sulfide)benzene, 1,3-bis(4-aminophenyl sulfide)benzene, 1,4-bis(4-aminophenyl sulfide)benzene, 1,3-bis(3-aminophenyl sulfone)benzene, 1,3-Bis(4-aminophenylsulfone)benzene, 1,4-bis(4-aminophenylsulfone)benzene, 1,3-bis[2-(4-aminophenyl)isopropyl]benzene, 1,4-bis[2-(3-aminophenyl)isopropyl]benzene, 1,4-bis[2-(4-aminophenyl)isopropyl]benzene, 3,3'-bis(3-aminophenoxy)biphenyl, 3,3'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)biphenyl, bis[3-(3-aminophenoxy)phenyl]ether, bis[3-(4-aminophenoxy)phenyl]ether, bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-aminophenoxy) )phenyl]ether, bis[3-(3-aminophenoxy)phenyl]ketone, bis[3-(4-aminophenoxy)phenyl]ketone, bis[4-(3-aminophenoxy)phenyl]ketone, bis[4-(4-aminophenoxy)phenyl]ketone, bis[3-(3-aminophenoxy)phenyl]thioether, bis[3-(4-aminophenoxy)phenyl]thioether, bis[4-(3-aminophenoxy)phenyl]thioether, bis[4-(4-aminophenoxy)phenyl]thioether, bis[3-(3-aminophenoxy)phenyl]sulfone, bis[3-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[3-(3-aminophenoxy)phenyl]sulfone, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[3-(3-aminophenoxy)phenyl]sulfone, bis[3-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[3-(3-aminophenoxy)phenyl]sulfone bis[3-(4-aminophenoxy)phenyl]methane, bis[3-(4-aminophenoxy)phenyl]methane, bis[4-(3-aminophenoxy)phenyl]methane, bis[4-(4-aminophenoxy)phenyl]methane, 2,2-bis[3-(3-aminophenoxy)phenyl]propane, 2,2-bis[3-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP), 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 2,2-bis[3-(4-aminophenoxy)phenyl]-1,1,1,3,3 ,3-hexafluoropropane, 2,2-bis[4-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane and 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, etc., in particular, it can be at least one selected from the group consisting of p-phenylenediamine (PPD), 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine), 4,4'-oxydiphenylamine (ODA) and 1,3-bis(4-aminophenoxy)benzene (TPE-R), more particularly, it can be p-phenylenediamine (PPD) and 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine). ,

[0036] In an embodiment, the polyamic acid contains a mixture of dianhydride monomers and diamine monomers as polymerization units, the dianhydride monomers including pyromellitic dianhydride (PMDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (sBPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA) and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA), and the diamine monomers including p-phenylenediamine (PPD) and 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine).

[0037] Here, in the total dianhydride monomer component, pyromellitic dianhydride (PMDA) may be used in an amount of 20 mol% or more to 80 mol% or less (preferably, 22 mol% or more, 24 mol% or more, 26 mol% or more, 28 mol% or more, 30 mol% or more, 31 mol% or more, 32 mol% or more, 33 mol% or more, 34 mol% or more, 35 mol% or more, 36 mol% or more, 37 mol% or more, 38 mol% or more, 39 mol% or more or 40 mol% or more, wherein the upper limit thereof may be 80 mol%. % or less, 75 mol % or less, 70 mol % or less, 65 mol % or less, 60 mol % or less, 55 mol % or less, 50 mol % or less, 48 ​​mol % or less, 46 mol % or less, 44 mol % or less, 42 mol % or less, 40 mol % or less, 39 mol % or less, 38 mol % or less, 37 mol % or less, 36 mol % or less, 35 mol % or less, 34 mol % or less, 33 mol % or less, 32 mol % or less, 31 mol % or less or 30 mol % or less) are included in amounts including 35 mol % or less, 36 mol % or less, 37 mol % or less, 38 mol % or less, 39 mol % or less, 38 mol % or less, 37 mol % or less, 36 mol % or less, 35 mol % or less, 34 mol % or less, 33 mol % or less, 32 mol % or less, 31 mol % or less or 30 mol % or less.

[0038] In addition, among the total dianhydride monomer components, 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) may be used in an amount of 10 mol% or more to 50 mol% or less (preferably, 10 mol% or more, 15 mol% or more, 20 mol% or more, 22 mol% or more, 24 mol% or more, 26 mol% or more, 28 mol% or more, 30 mol% or more, 31 mol% or more, 32 mol% or more, 33 mol% or more, 34 mol% or more, 35 mol% or more, 36 mol% or more, 37 mol% or more). % or less, 38 mol% or more, 39 mol% or more or 40 mol% or more, wherein their upper limits may be 50 mol% or less, 48 ​​mol% or less, 46 mol% or less, 44 mol% or less, 42 mol% or less, 40 mol% or less, 39 mol% or less, 38 mol% or less, 37 mol% or less, 36 mol% or less, 35 mol% or less, 34 mol% or less, 33 mol% or less, 32 mol% or less, 31 mol% or less or 30 mol% or less) in an amount included.

[0039] In addition, among the total dianhydride monomer components, 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA) and / or 3,3',4,4'-biphenyltetracarboxylic dianhydride (sBPDA) may be used in an amount of 10 mol% or more to 50 mol% or less (preferably, 10 mol% or more, 15 mol% or more, 20 mol% or more, 22 mol% or more, 24 mol% or more, 26 mol% or more, 28 mol% or more, 30 mol% or more, 31 mol% or more, 32 mol% or more, 33 mol% or more, 34 mol% or more, 35 mol% or more, 36 mol% or more). % or less, 37 mol% or more, 38 mol% or more, 39 mol% or more or 40 mol% or more, wherein their upper limits may be 50 mol% or less, 48 ​​mol% or less, 46 mol% or less, 44 mol% or less, 42 mol% or less, 40 mol% or less, 39 mol% or less, 38 mol% or less, 37 mol% or less, 36 mol% or less, 35 mol% or less, 34 mol% or less, 33 mol% or less, 32 mol% or less, 31 mol% or less or 30 mol% or less) in an amount including.

[0040] In the present invention, in the polyamic acid, the amount of each dianhydride monomer component (including pyromellitic dianhydride (PMDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (sBPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA) and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA)) can be appropriately adjusted within the range where the total amount of the dianhydride monomer components is 100 mol%.

[0041] In an embodiment, the dianhydride monomer may include 20 mol % to 80 mol % of pyromellitic dianhydride (PMDA), 10 mol % to 50 mol % of 3,3',4,4'-biphenyltetracarboxylic dianhydride (sBPDA) and / or 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA), and 10 mol % to 50 mol % of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA).

[0042] In addition, among the total diamine monomer components, p-phenylenediamine (PPD) may be used in an amount of 10 mol% or more to 80 mol% or less (preferably, 10 mol% or more, 15 mol% or more, 20 mol% or more, 25 mol% or more, 30 mol% or more, 35 mol% or more, 40 mol% or more, 42 mol% or more, 44 mol% or more, 46 mol% or more, 48 mol% or more, 50 mol% or more, 52 mol% or more, 54 mol% or more, 56 mol% or more, 58 mol% or more, 60 mol% or more, 62 mol% or more). %, 64 mol% or more, 66 mol% or more, 68 mol% or more, 70 mol% or more, 72 mol% or more, 74 mol% or more or 76 mol% or more, wherein their upper limits may be 80 mol% or less, 78 mol% or less, 76 mol% or less, 74 mol% or less, 72 mol% or less, 70 mol% or less, 68 mol% or less, 66 mol% or less, 64 mol% or less, 62 mol% or less, 60 mol% or less, 55 mol% or less, 50 mol% or less or 45 mol% or less) are included.

[0043] In addition, among the total diamine monomer components, 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine) may be used in an amount of 20 mol% or more to 90 mol% or less (preferably, 22 mol% or more, 24 mol% or more, 26 mol% or more, 28 mol% or more, 30 mol% or more, 31 mol% or more, 32 mol% or more, 33 mol% or more, 34 mol% or more, 35 mol% or more, 36 mol% or more, 37 mol% or more, 38 mol% or more, 39 mol% or more or 40 mol% or more, wherein the upper limits thereof may be 90 mol% or less, 88 mol% or less, 86 mol% or less, 84 mol% or less, 82 mol% or less, % or less, 48 ​​mol% or less, 46 mol% or less, 44 mol% or less, 42 mol% or less, 40 mol% or less, 39 mol% or less, 38 mol% or less, 37 mol% or less, 36 mol% or less or 35 mol% or less) are included in amounts including but not limited to 35 mol% or less, 36 mol% or less, 37 mol% or less, 36 mol% or less, 37 mol% or less, 38 mol% or less, 39 mol% or less, 38 ...

[0044] In the present invention, in the polyamic acid, the amount of each diamine monomer component including p-phenylenediamine (PPD) and 2,2′-dimethyl-4,4′-diaminobiphenyl (m-tolidine) may be appropriately adjusted within a range in which the total amount of the diamine monomer components is 100 mol %.

[0045] In an embodiment, the diamine monomer includes 10 mol % to 80 mol % of p-phenylenediamine (PPD) and 20 mol % to 90 mol % of 2,2′-dimethyl-4,4′-diaminobiphenyl (m-tolidine).

[0046] In the present invention, the molar ratio of the diamine monomer to the dianhydride monomer may be 0.5 equivalent to 2 equivalents. The molar ratio may be particularly 0.8 equivalent to 1.5 equivalents. When the molar ratio is less than 0.5 equivalent or greater than 2 equivalents, the polyimide finally formed has a very small molecular weight, and therefore, there is a problem that the physical and chemical properties of the polyimide are very poor.

[0047] The black polyimide film according to the present invention can have a thickness of 3 μm to 100 μm, particularly, a thickness of 4 μm to 90 μm, more particularly, a thickness of 5 μm to 80 μm, and more particularly, a thickness of 5.5 μm to 75 μm. The thickness of the film is not particularly limited as long as it can be flexibly applied, and the thickness can be adjusted in consideration of mechanical strength, handling, productivity, etc.

[0048] The black polyimide film of the present invention has a light transmittance of 0.2% or less in the visible light region, a glossiness (60°) of 50 or less, a dielectric constant (Dk) of 4.0 or less, and a dielectric loss factor (Df) of 0.01 or less.

[0049] Furthermore, the black polyimide film of the present invention can satisfy all conditions in which the transmittance in the visible light region is 0.2% or less, the glossiness (60°) is 50 or less, the dielectric constant (Dk) is 4.0 or less, and the dielectric loss factor (Df) is 0.01 or less.

[0050] As an example, the dielectric constant of the black polyimide film according to the present invention at 10 GHz may be 4.0 or less, preferably 3.9 or less, wherein their lower limit may be at least 3.0. It is understood that the polyimide film exhibits an ideal dielectric constant as an insulator, considering that the engineering properties of the polyimide film are at the highest level.

[0051] In addition, the dielectric loss factor of the black polyimide film according to the present invention at 10GHz can be 0.01 or less, preferably, 0.0099 or less, wherein their lower limit can be at least 0.005 or greater. "Dielectric loss factor" means the force dissipated by a dielectric (or insulator) when molecular friction hinders the molecular motion caused by an alternating electric field, and the value of the dielectric loss factor is generally used as an index indicating the ease of charge dissipation (dielectric loss), wherein when the dielectric loss factor is high, the charge is easier to dissipate, on the contrary, when the dielectric loss factor is low, the charge dissipation can be difficult. In other words, since the dielectric loss factor is a measure of power loss, the lower the dielectric loss factor, the faster the communication speed can be maintained while reducing the delay in signal transmission caused by power loss.

[0052] Therefore, the polyimide film of the present invention has an advantage in that insulation is easily maintained even in an electronic device for high-speed transmission operating at a frequency of a gigahertz (GIGA) unit (eg, 10 GHz or more).

[0053] In addition, the light transmittance of the black polyimide film according to the present invention can be, for example, 0.2% or less, preferably, 0.18% or less, wherein their lower limit can be at least 0.01%.It is understood that the polyimide film has properties suitable for use as a cover film.

[0054] In addition, the glossiness (60°) of the black polyimide film according to the present invention may be, for example, 50 or less, preferably 48 or less, wherein their lower limits may be at least 1. When the glossiness exceeds 50, there may be problems of reduced visual beauty and poor covering function.

[0055] Therefore, when the polyimide film satisfies all of the dielectric constant, dielectric loss factor, glossiness and transmittance, the polyimide film can be used as an insulating film for a covering film, and even if the manufactured covering film is used for an electrical signal transmission circuit that transmits signals at a high frequency of 10 GHz or higher, the insulation stability of the covering film can be ensured and the delay in signal transmission can be minimized.

[0056] The black polyimide film of the present invention having all the above conditions is a hitherto unknown novel black polyimide film.

[0057] Method for producing black polyimide film of the present invention

[0058] In addition, another embodiment of the present invention provides a method for producing a black polyimide film, the method comprising:

[0059] (1) polymerizing a polyamic acid solution from at least one dianhydride monomer and at least one diamine monomer;

[0060] (2) preparing a polyimide precursor composition by mixing a polyamic acid solution with a black pigment containing bituminous coal and lactam black; and

[0061] (3) The polyimide precursor composition is formed into a film on a support, and then subjected to heat treatment and imidization.

[0062] In the method for producing a black polyimide film, the "dianhydride monomer" and the "diamine monomer" are the same as described above, and the method for producing a black polyimide film of the present invention may be a method for forming a polyimide film as a whole.

[0063] In an embodiment, in step (1), polyamic acid solution is obtained by reacting dianhydride and diamine using an organic solvent. Here, the solvent is not particularly limited, as long as polyamic acid can be dissolved, but the solvent can be, for example, aprotic polar solvent. As solvent, N-methylpyrrolidone (NMP), N,N'-dimethylformamide (DMF), N,N'-diethylformamide (DEF), N,N'-dimethylacetamide (DMAc), dimethylpropionamide (DMPA), N,N-diethylacetamide (685-91-6, DEAc), 3-methoxy-N,N-dimethylpropionamide (53185-52-7, KJCMPA) etc. can be preferably used alone or in combination, but most preferably N-methylpyrrolidone (NMP).

[0064] In the present invention, the weight-average molecular weight (weight-average molecular weight) of the polyamic acid solution of the present invention can be 100000g / mol to 300000g / mol.The lower limit of weight-average molecular weight can be 100000g / mol, 120000g / mol, 150000g / mol or 200000g / mol or larger, and the upper limit of weight-average molecular weight can be 300000g / mol, 280000g / mol, 270000g / mol, 260000g / mol or 250000g / mol or smaller.

[0065] In the present invention, the weight of the monomer added to the whole polyamic acid solution in a state where diamine and dianhydride are added in substantially equimolar amounts is referred to as solid content, wherein the polyamic acid solution may have a solid content of 5% to 30% by weight. The lower limit of the weight percentage of the solid content may be 5% by weight, 8% by weight, 9% by weight, 10% by weight, 15% by weight, 20% by weight, 21% by weight, 22% by weight, 23% by weight, 24% by weight, 25% by weight, 26% by weight, 27% by weight, 28% by weight or 29% by weight or more, and the upper limit of the weight percentage of the solid content may be 29% by weight, 27% by weight, 25% by weight, 23% by weight, 21% by weight, 20% by weight, 19% by weight or 18% by weight or less. By adjusting the solid content of the polyamic acid solution, the viscosity increase during the curing process can be controlled and the process time can be shortened.

[0066] In the present invention, the polyamic acid solution may have a viscosity in the range of 20000 cP to 400000 cP, which is 23° C. at a temperature of 1 s. -1The viscosity can be measured under the conditions of a shear rate of 1 / s, a temperature of 23°C and a plate gap of 1mm using, for example, Haake's Rheostress600. The present invention can provide a precursor composition with excellent processability by adjusting the viscosity range.

[0067] In step (2), the bituminous coal and lactam black contained in the polyimide precursor composition can be ground through a grinding process to adjust the particle size, thereby increasing the dispersion so as to be uniformly mixed when mixed with the polyamic acid solution, while reducing the gloss, transmittance, dielectric constant and dielectric loss factor.

[0068] In this regard, before step (2), the manufacturing method may further include the step of grinding with a grinder to respectively manufacture bituminous coal having an average particle size (D50) of 0.5 μm to 10 μm and lactam black having an average particle size (D50) of 30 nm to 1000 nm.

[0069] In an embodiment, a bead mill using beads having a particle size of 1.0 mm to 2.0 mm may be used to perform a grinding process to produce bituminous coal and / or lactam black having a particle size within the above range, wherein the grinding process may be performed on bituminous coal and lactam black separately or the bituminous coal and lactam black may be combined to perform a grinding process. During the grinding process, the stirring speed and the grinding time may be appropriately adjusted according to the desired particle size, so these conditions are not particularly limited. In addition, bituminous coal and / or lactam black having a particle size within the above range may be produced by grinding using a bead mill using beads having a particle size of 0.8 mm to 1.5 mm.

[0070] In addition, in step (2), the black pigment includes bituminous coal and lactam black dispersed in an organic solvent, wherein the organic solvent can be at least one selected from the group consisting of N-methylformamide, N,N'-dimethylformamide (DMF), N-methylformanilide, N,N'-dimethylacetamide (DMAC), N-methylpyrrolidone (NMP), propylene glycol methyl ether acetate (PGMEA), ethylene glycol acetate, propylene glycol monomethyl ether acetate, dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether and acetylacetone, preferably, it can be at least one selected from the group consisting of N,N'-dimethylformamide (DMF), N,N'-dimethylacetamide (DMAC), N-methylpyrrolidone (NMP) and propylene glycol methyl ether acetate (PGMEA).

[0071] In the present invention, step (3) comprises forming a gel film by casting the polyimide precursor composition prepared in step (2) on a support and drying it, and then imidizing the gel film to form a black polyimide film.

[0072] In the process of forming the gel film, the polyimide precursor composition may be subjected to casting the polyimide precursor composition on a carrier (such as an aluminum foil, an endless stainless steel belt, or a stainless steel barrel) to become a film form, and then drying the precursor composition on the carrier at a variable temperature in the range of 50° C. to 200° C. (particularly, 80° C. to 150° C.).

[0073] Imidization can be performed by heat treatment, wherein the heat treatment can be performed at a variable temperature in the range of 50°C to 500°C (particularly, 150°C to 500°C) to remove residual water, residual solvent, etc., and imidize almost all of the remaining amic acid groups, thereby manufacturing the black polyimide film of the present invention. In some cases, the polyimide film obtained as described above can be further cured by heat-finishing the polyimide film at a temperature of 400°C to 650°C for 5 seconds to 400 seconds, and in order to relieve the internal stress that may remain in the obtained polyimide film, the polyimide film can be cured under a predetermined tension.

[0074] The present invention provides a cover film comprising the black polyimide film as described above and an electronic device for high-speed transmission comprising the cover film as described above.

[0075] Beneficial Effects

[0076] The black polyimide film of the present invention includes a black pigment containing a combination of bituminous coal and black lactam, thereby having low gloss and light transmittance, resulting in excellent optical properties, and having a low dielectric constant and dielectric loss factor, resulting in excellent low dielectric properties. DETAILED DESCRIPTION

[0077] The following examples are provided to facilitate understanding of the present invention. These examples are provided only to make it easier to understand the present invention, but the content of the present invention is not limited to the following examples.

[0078] <Example>

[0079] Example 1: Preparation of polyimide precursor composition

[0080] Example 1-1

[0081] For polyamic acid solution polymerization process, under nitrogen atmosphere, 408.62g of dimethylformamide (DMF) was added as solvent in 500mL reactor. After temperature was set to 25°C, PPD (66mol%) and m-tolidine (34mol%) were added as diamine monomers, and stirred for 30 minutes to confirm that the monomer was dissolved. Then, PMDA (35mol%), BTDA (33mol%) and BPDA (32mol%) were added as dianhydride monomers, and stirred to react until viscosity did not change, thereby obtaining polyamic acid solution.

[0082] A polyimide precursor composition was prepared by mixing the polyamic acid solution prepared above with a black pigment containing bituminous coal (6.6% by weight) and lactam black (4.5% by weight) dispersed in an organic solvent. The polyimide precursor composition contained the black pigment in an amount of 11.1% by weight in total.

[0083] Example 1-2

[0084] A polyimide precursor composition was prepared in the same manner as in Example 1-1, except that a black pigment containing bituminous coal (6.6% by weight) and lactam black (5.5% by weight) was used instead of the black pigment containing bituminous coal (6.6% by weight) and lactam black (4.5% by weight) in Example 1-1. The polyimide precursor composition contained the black pigment in a total amount of 12.1% by weight.

[0085] Examples 1-3

[0086] A polyimide precursor composition was prepared in the same manner as in Example 1-1, except that a black pigment containing bituminous coal (6.6% by weight) and lactam black (6.5% by weight) was used instead of the black pigment containing bituminous coal (6.6% by weight) and lactam black (4.5% by weight) in Example 1-1. The polyimide precursor composition contained the black pigment in a total amount of 13.1% by weight.

[0087] Examples 1-4

[0088] A polyimide precursor composition was prepared in the same manner as in Example 1-1, except that a black pigment containing bituminous coal (6.6% by weight) and lactam black (7.5% by weight) was used instead of the black pigment containing bituminous coal (6.6% by weight) and lactam black (4.5% by weight) in Example 1-1. The polyimide precursor composition contained the black pigment in a total amount of 14.1% by weight.

[0089] The components and contents of the polyimide precursor compositions prepared according to Example 1-1 to Example 1-4 are summarized in Table 1 below (wherein the weight percentage (%) of the black pigment represents the content in the polyimide precursor composition).

[0090] Table 1

[0091]

[0092] Comparative Example 1: Preparation of polyimide precursor composition

[0093] Comparative Example 1-1 (excluding black pigment)

[0094] For polyamic acid solution polymerization process, 408.62g of dimethylformamide (DMF) was added as solvent in a 500mL reactor under a nitrogen atmosphere. After the temperature was set to 25°C, PPD (66mol%) and m-tolidine (34mol%) were added as diamine monomers, and stirred for 30 minutes to confirm that the monomers were dissolved. Then, PMDA (35mol%), BTDA (33mol%) and BPDA (32mol%) were added as dianhydride monomers, and stirred to react until viscosity did not change, thereby obtaining a polyimide precursor composition.

[0095] Comparative Example 1-2 (comprising only soft coal as black pigment)

[0096] A polyimide precursor composition was prepared in the same manner as in Example 1-1, except that a black pigment containing only bituminous coal (6.6% by weight) was used instead of the black pigment containing bituminous coal (6.6% by weight) and lactam black (4.5% by weight) in Example 1-1. The polyimide precursor composition contained the black pigment in an amount of 6.6% by weight in total.

[0097] Comparative Examples 1-3 (comprising soft coal and carbon black as black pigments)

[0098] A polyimide precursor composition was prepared in the same manner as in Example 1-1, except that a black pigment containing bituminous coal (6.6% by weight) and carbon black (2.5% by weight) was used instead of the black pigment containing bituminous coal (6.6% by weight) and lactam black (4.5% by weight) used in Example 1-1. The polyimide precursor composition contained the black pigment in a total amount of 9.1% by weight.

[0099] Comparative Examples 1-4 (containing only lactam black as black pigment)

[0100] A polyimide precursor composition was prepared in the same manner as in Example 1-1, except that a black pigment containing only lactam black (6.5% by weight) was used instead of the black pigment containing bituminous coal (6.6% by weight) and lactam black (4.5% by weight) used in Example 1-1. The polyimide precursor composition contained the black pigment in an amount of 6.5% by weight in total.

[0101] The components and contents of the polyimide precursor compositions prepared according to Comparative Example 1-1 to Comparative Example 1-4 are summarized in Table 2 below.

[0102] Table 2

[0103]

[0104]

[0105] Example 2: Preparation of black polyimide film

[0106] Example 2-1

[0107] The polyimide precursor composition prepared in Example 1-1 was subjected to casting on a SUS plate (100SA, Sandvik) to a thickness of 70 μm using a doctor blade, and then dried at a temperature range of 100° C. to 200° C. Then, the film was peeled off the SUS plate, fixed to a pin frame, and transferred to a high-temperature tenter. The film was heated from 200° C. to 600° C. in a high-temperature tenter, cooled at 25° C., and separated from the pin frame, thereby manufacturing a black polyimide film having a thickness of 12.5±0.5 μm, the black polyimide film containing 6.6% by weight of bituminous coal and 4.5% by weight of lactam black based on the total weight of the polyimide film.

[0108] Example 2-2

[0109] A black polyimide film was manufactured in the same manner as in Example 2-1, except that the polyimide precursor composition prepared in Example 1-2 was used instead of the polyimide precursor composition of Example 1-1, and the black polyimide film contained 6.6% by weight of bituminous coal and 5.5% by weight of lactam black based on the total weight of the polyimide film.

[0110] Example 2-3

[0111] A black polyimide film was manufactured in the same manner as in Example 2-1, except that the polyimide precursor composition prepared in Example 1-3 was used instead of the polyimide precursor composition of Example 1-1, and the black polyimide film contained 6.6% by weight of bituminous coal and 6.5% by weight of lactam black based on the total weight of the polyimide film.

[0112] Embodiment 2-4

[0113] A black polyimide film was manufactured in the same manner as in Example 2-1, except that the polyimide precursor composition prepared in Example 1-4 was used instead of the polyimide precursor composition of Example 1-1, and the black polyimide film contained 6.6% by weight of bituminous coal and 7.5% by weight of lactam black based on the total weight of the polyimide film.

[0114] Comparative Example 2: Preparation of polyimide film

[0115] Comparative Example 2-1 (excluding black pigment)

[0116] A polyimide film was manufactured in the same manner as in Example 2-1 except that the polyimide precursor composition prepared in Comparative Example 1-1 was used instead of the polyimide precursor composition of Example 1-1. The polyimide film of Comparative Example 2-1 did not include a black pigment.

[0117] Comparative Example 2-2 (comprising only bituminous coal as black pigment)

[0118] A black polyimide film containing 6.6% by weight of bituminous coal based on the total weight of the polyimide film was manufactured in the same manner as in Example 2-1, except that the polyimide precursor composition prepared in Comparative Example 1-2 was used instead of the polyimide precursor composition of Example 1-1.

[0119] Comparative Example 2-3 (comprising bituminous coal and carbon black as black pigment)

[0120] A black polyimide film was manufactured in the same manner as in Example 2-1, except that the polyimide precursor composition prepared in Comparative Example 1-3 was used instead of the polyimide precursor composition of Example 1-1, and the black polyimide film contained 6.6% by weight of bituminous coal and 2.5% by weight of carbon black based on the total weight of the polyimide film.

[0121] Comparative Example 2-4 (comprising only lactam black as black pigment)

[0122] A black polyimide film containing 6.5% by weight of lactam black based on the total weight of the polyimide film was manufactured in the same manner as in Example 2-1, except that the polyimide precursor composition prepared in Comparative Example 1-4 was used instead of the polyimide precursor composition of Example 1-1.

[0123] Experimental Examples

[0124] Experimental Example 1. Evaluation of glossiness

[0125] The glossiness was measured at an angle of 60° according to the ASTM D523 method using a glossiness measuring device (PG-IIM manufactured by NIPPON DENSHOKU), and the results are shown in Table 3 below.

[0126] Experimental Example 2. Evaluation of light transmittance

[0127] The light transmittance was measured in the visible light region according to the ASTM D1003 method using a light transmittance measuring device (ColorQuesetXE manufactured by HunterLab), and the results are shown in Table 3 below.

[0128] Experimental Example 3. Evaluation of Dielectric Constant (Dk)

[0129] The dielectric constant was measured at 10 GHz using a split postdielectric resonator (SPDR) manufactured by Keysight Technologies, and the results are shown in Table 3 below.

[0130] Experimental Example 4. Dielectric loss factor (Df)

[0131] Copper foil lamination was performed on both sides of the polyimide film to prepare a flexible metal clad laminate. The dielectric loss factor (Df) was measured by leaving the flexible metal clad laminate for 72 hours using an Agilent 4294A ohmmeter, and the results are shown in Table 3 below.

[0132] Table 3

[0133]

[0134] With reference to Table 3, the black polyimide film of the present invention satisfies all conditions of 0.2% or less transmittance, 50 or less glossiness, 4.0 or less dielectric constant, and 0.01 or less dielectric loss factor. However, it can be confirmed that the comparative example 2-1 without black pigment and the comparative example 2-4 containing only lactam black as black pigment have very high transmittance and glossiness, and the comparative example 2-2 containing only bituminous coal as black pigment has a transmittance far exceeding 0.2%. In addition, it can be confirmed that the comparative example 2-3 containing bituminous coal and carbon black as black pigment has a high dielectric constant of 4.61 and a high dielectric loss factor of 0.03082.

[0135] In the specification, detailed descriptions of contents that can be fully recognized and inferred by those skilled in the art to which the present disclosure belongs are omitted, and in addition to the specific exemplary embodiments described in the specification, many changes and modifications can be made within the scope of not changing the technical spirit or basic configuration (construction) of the present invention. Therefore, it can be understood by those skilled in the art that the present disclosure can also be practiced in a manner different from that specifically described and shown here.

Claims

1. A black polyimide film, comprising a black pigment, wherein the black pigment comprises bituminous coal and lactam black, in, The black polyimide film is formed by imidizing a polyamic acid obtained from a dianhydride monomer and a diamine monomer.

2. The black polyimide film according to claim 1, wherein The black polyimide film includes 3 to 15% by weight of the bituminous coal and 2 to 15% by weight of the lactam black, based on the total weight of the black polyimide film.

3. The black polyimide film according to claim 1, wherein The black polyimide film includes 5 to 10% by weight of the bituminous coal and 4 to 10% by weight of the lactam black, based on the total weight of the black polyimide film.

4. The black polyimide film according to claim 1, wherein The bituminous coal has an average particle size (D50) of 0.5 μm to 10 μm.

5. The black polyimide film according to claim 1, wherein The lactam black has an average particle size (D50) of 30 nm to 1000 nm.

6. The black polyimide film according to claim 1, wherein The dianhydride monomer is at least one selected from the group consisting of: Pyromellitic dianhydride (PMDA), oxydiphthalic dianhydride (ODPA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (sBPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA), diphenyl sulfone-3,4,3',4'-tetracarboxylic dianhydride (DSDA), bis(3,4-dicarboxyphenyl)sulfide dianhydride, 2,2-bis(3,4-dicarboxyphenyl)-1,1,1,3,3,3-hexafluoropropane dianhydride, 2,3,3',4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA), bis(3,4-dicarboxyphenyl)methane dianhydride, 2,2-bis(3,4- 1,4-bis(3,4-dicarboxyphenoxy)phthalic acid dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)phthalic acid dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)phthalic acid dianhydride, 2,2-bis[(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (BPADA), 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride and 4,4'-(2,2-hexafluoroisopropylidene)diphthalic acid dianhydride.

7. The black polyimide film according to claim 1, wherein: The diamine monomer is at least one selected from the group consisting of: p-phenylenediamine (PPD), m-phenylenediamine, 3,3'-dimethylbenzidine, 2,2'-dimethylbenzidine, 2,4-diaminotoluene, 2,6-diaminotoluene, 3,5-diaminobenzoic acid (DABA), 4,4'-oxydiphenylamine (ODA), 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane (4,4'-methylenedianiline), 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine), 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-dicarboxy-4, 4'-diaminodiphenylmethane, 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane, bis(4-aminophenyl) sulfide, 4,4'-diaminobenzanilide, 3,3'-dimethoxybenzidine, 2,2'-dimethoxybenzidine, 3,3'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-diamino-4,4'-dichlorobenzophenone, 3,3'-diamino-4,4'-dimethyl Oxybenzophenone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2-bis(3-aminophenyl)propane, 2,2-bis(4-aminophenyl)propane, 2,2-bis(3-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-bis(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 3,3'-diaminodiphenyl sulfoxide, 3,4'-diaminodiphenyl sulfoxide, 4,4'-diaminodiphenyl sulfoxide, 1,3-bis(3-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(3-aminophenyl)benzene, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenoxy)benzene (TP E-R), 1,4-bis(3-aminophenoxy)benzene (TPE-Q), 1,3-bis(3-aminophenoxy)-4-trifluoromethylbenzene, 3,3'-diamino-4-(4-phenylphenoxy)benzophenone, 3,3'-diamino-4,4'-di(4-phenylphenoxy)benzophenone, 1,3-bis(3-aminophenyl sulfide)benzene, 1,3-bis(4-aminophenyl sulfide)benzene, 1,4-bis(4-aminophenyl sulfide)benzene, 1,3-bis(3-aminophenyl sulfone)benzene, 1,3-bis(4-aminophenyl sulfone)benzene, 1,4-bis(4-aminophenyl sulfone)benzene, 1,3-bis[2-(4-aminophenyl)isopropyl]benzene, 1,4-bis[2-(3-aminophenyl)isopropyl]benzene, 1,4-Bis[2-(4-aminophenyl)isopropyl]benzene, 3,3'-bis(3-aminophenoxy)biphenyl, 3,3'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)biphenyl, bis[3-(3-aminophenoxy)phenyl]ether, bis[3-(4-aminophenoxy)phenyl]ether, bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-aminophenoxy)phenyl]ether, bis[3-(3-aminophenoxy) phenyl] ketone, bis[3-(4-aminophenoxy)phenyl] ketone, bis[4-(3-aminophenoxy)phenyl] ketone, bis[4-(4-aminophenoxy)phenyl] ketone, bis[3-(3-aminophenoxy)phenyl] sulfide, bis[3-(4-aminophenoxy)phenyl] sulfide, bis[4-(3-aminophenoxy)phenyl] sulfide, bis[4-(4-aminophenoxy)phenyl] sulfide, bis[3-(3-aminophenoxy)phenyl] sulfide, bis[4-(4-aminophenoxy)phenyl] sulfide, bis[3-(3-aminophenoxy)phenyl] sulfone, bis[3-(4-aminophenoxy)phenyl] sulfone, bis[4-(3-aminophenoxy)phenyl] sulfone, bis[3-(3-aminophenoxy)phenyl]methane, bis[3-(4-aminophenoxy)phenyl]methane, bis[4-(3-aminophenoxy)phenyl]methane, bis[4-(4-aminophenoxy)phenyl]methane, 2,2-bis[3-(3-aminophenoxy)phenyl]propane, 2,2-bis[3-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2 -bis[4-(4-aminophenoxy)phenyl]propane (BAPP), 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 2,2-bis[3-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 2,2-bis[4-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane and 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane.

8. The black polyimide film according to claim 1, wherein The dianhydride monomer is at least one selected from the group consisting of pyromellitic dianhydride (PMDA), oxydiphthalic dianhydride (ODPA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (sBPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA) and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA), and The diamine monomer is at least one selected from the group consisting of p-phenylenediamine (PPD), 2,2′-dimethyl-4,4′-diaminobiphenyl (m-tolidine), 4,4′-oxydiphenylamine (ODA), and 1,3-bis(4-aminophenoxy)benzene (TPE-R).

9. The black polyimide film according to claim 1, wherein: The dianhydride monomer comprises 20 mol % to 80 mol % of pyromellitic dianhydride (PMDA), 10 mol % to 50 mol % of 3,3',4,4'-biphenyltetracarboxylic dianhydride (sBPDA) and / or 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA), and 10 mol % to 50 mol % of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA), and The diamine monomer includes 10 mol % to 80 mol % of p-phenylenediamine (PPD) and 20 mol % to 90 mol % of 2,2′-dimethyl-4,4′-diaminobiphenyl (m-tolidine).

10. The black polyimide film according to claim 1, wherein The black polyimide film has a thickness of 3 μm to 100 μm.

11. The black polyimide film according to claim 1, wherein The black polyimide film has: A light transmittance of 0.2% or less in the visible light region; Gloss of 50 or less (60°); A dielectric constant (Dk) of 4.0 or less; and Dielectric dissipation factor (Df) of 0.01 or less.

12. A method for manufacturing a black polyimide film, the method comprising: (1) polymerizing a polyamic acid solution from at least one dianhydride monomer and at least one diamine monomer; (2) preparing a polyimide precursor composition by mixing the polyamic acid solution with a black pigment comprising bituminous coal and lactam black; as well as (3) Forming the polyimide precursor composition into a film on a support, followed by heat treatment and imidization.

13. The manufacturing method according to claim 12, further comprising: Prior to step (2), bituminous coal having an average particle size (D50) of 0.5 μm to 10 μm and lactam black having an average particle size (D50) of 30 nm to 1000 nm are ground with a grinder to respectively produce.

14. The manufacturing method according to claim 12, wherein: In step (2), the black pigment includes bituminous coal and lactam black dispersed in an organic solvent.

15. The manufacturing method according to claim 14, wherein: The organic solvent is at least one selected from the group consisting of N-methylformamide, N,N'-dimethylformamide (DMF), N-methylformanilide, N,N'-dimethylacetamide (DMAC), N-methylpyrrolidone (NMP), propylene glycol methyl ether acetate (PGMEA), ethylene glycol acetate, propylene glycol monomethyl ether acetate, dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether and acetylacetone. 16 . A cover film, comprising the black polyimide film according to claim 1 .

17. An electronic device for high-speed transmission, comprising the cover film according to claim 16.

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