Black polyimide film and method for producing the same

Abstract

The present invention provides a black polyimide film obtained by imidizing a polyamic acid obtained from a dianhydride monomer and a diamine monomer, the black polyimide film containing black pigments including bituminous coal and perylene black.

Description

[Technical Field]

[0001] The present invention relates to a black polyimide film and a method for producing the same, and more particularly to a black polyimide film containing a black pigment, which has low dielectric constant, low gloss and low transmittance, and a method for producing the same. [Background technology]

[0002] Polyimide is a general term for polymers with an acid imide structure, and is generally formed by the condensation reaction of aromatic acid anhydrides and aromatic diamines. It has excellent properties such as high heat resistance, able to withstand temperatures from extremely low to over 400°C, electrical insulation, radiation resistance, and chemical resistance, and is therefore used in a wide range of fields as advanced materials and insulating coating agents in the electrical and electronics, semiconductor, display, automotive, aviation, and space materials fields.

[0003] However, its use has been limited due to its "insoluble and infusible" characteristics, meaning that it cannot be dissolved in solvents or molded by heating. Therefore, most polyimides are manufactured by processing the precursor polyamic acid, subjecting it to high-temperature heat treatment, and then curing it to imidization, and the most representative product produced by this method is polyimide film.

[0004] Recently, polyimides have been widely used as coverlays in portable electronic devices and communication devices. Coverlays are used to protect electronic components such as printed wiring boards and lead frames of semiconductor integrated circuits, and require physical properties such as thinness and slimness. Recently, there has been a demand for coverlays that offer security, portability, visual effects, and the ability to conceal electronic components and mounted parts, as well as optical properties.

[0005] Generally, both quenchers and color additives (e.g., pigments or dyes) are used in the production of polyimide films. In conventional manufacturing processes, color additives (e.g., carbon black) are typically added to reduce the transparency of polyimide films, while quenchers such as SiO2 can be added to reduce the gloss of polyimide films. However, neither color additives nor quenchers alone can achieve quenching or reduce transparency. Therefore, conventional manufacturing processes require the use of large amounts of color additives and quenchers to impart the desired properties to polyimide films. This not only causes problems such as operational issues and poor dispersion of the additives, but also results in high dielectric constants and dielectric loss factors, making them difficult to integrate into 5G electronic devices.

[0006] Therefore, in order to realize a polyimide film having a low dielectric constant, a low dielectric loss factor, a low gloss and a low transmittance without adding a quencher, there is a need to develop a black polyimide film for high-speed transmission containing an optimal combination of black pigments. Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention provides a black polyimide film which contains a black pigment with controlled particle size in a polyimide, and which has excellent optical properties such as gloss and transmittance, as well as a low dielectric constant and dielectric loss factor.

[0008] The present invention also provides a method for producing the black polyimide film.

[0009] The present invention also provides a coverlay comprising the black polyimide film.

[0010] The present invention also provides an electronic device for high-speed transmission that includes the coverlay. [Means for solving the problem]

[0011] Hereinafter, the embodiments of the present invention will be described in more detail, starting with the "black polyimide film" according to the present invention and the "method for producing a black polyimide film."

[0012] Since the present invention can be modified in various ways and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail, but it should be understood that this does not limit the present invention to the specific embodiments, and that the present invention includes all modifications, equivalents, and alternatives that fall within the spirit and technical scope of the present invention.

[0013] The terms used in this application are merely used to describe specific embodiments and are not intended to limit the present invention. The singular expressions include the plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" and the like specify the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and should be understood not to preclude the presence or additional possibility of one or more different features, numbers, steps, operations, components, parts, or combinations thereof.

[0014] Whenever an amount, concentration, or other value or parameter is given herein by a list of ranges, preferred ranges, or upper preferred values ​​and lower preferred values, that should 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 otherwise disclosed.

[0015] Where a range of numerical values ​​is recited herein, unless otherwise stated, it is intended that the endpoints of the range and the scope of the invention within that range are not limited to the specific values ​​recited when defining the range.

[0016] As used herein, "dianhydride" is intended to include precursors or derivatives thereof, but may also be referred to as "dianhydride acids," "dianhydrides," or "acid dianhydrides," which may not technically be dianhydrides but nevertheless react with diamines to form polyamic acids, which in turn can be converted to polyimides.

[0017] As used herein, "diamine" is intended to include precursors or derivatives thereof, which may not technically be diamines, but which nevertheless react with dianhydride acids to form polyamic acids, which in turn can be converted to polyimides.

[0018] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which this invention pertains. Terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant art, and should not be interpreted in an ideal or overly formal sense unless expressly defined in this application. Specific details for realizing the above invention are described below.

[0019] Black Polyimide Film The present invention provides a black polyimide film obtained by imidizing a polyamic acid obtained from a dianhydride monomer and a diamine monomer, the black polyimide film including a black pigment including bituminous coal and perylene black.

[0020] Bituminous coal, also known as bituminous coal, is black or dark black, has a glassy or resinous luster, and contains a high amount of volatile matter. In the present invention, bituminous coal may contain up to 20% volatile matter and about 75% fixed carbon, but is not limited thereto. It may also contain up to 1% moisture, up to 0.9% SO2, and about 7.5% ash. Since the polyimide film of the present invention contains bituminous coal, its gloss may be low.

[0021] As the bituminous coal, for example, Mineral Black 325 BA (Keystone Filley & Mfg. Co.), Austin Black 325 (Coal Fillers Inc.), or a combination thereof can be used. In the embodiment of the present invention, Austin Black 325 manufactured by Coal Fillers Inc. is used.

[0022] Perylene black is any one of the black organic pigments that have a perylene structure in their molecules, absorb light in the visible wavelength range, and exhibit a black color.

[0023] Examples of perylene black include Pigment Black 31 and Pigment Black 32 (all numbers are CI numbers). Other perylene blacks that can be used include PALIOGEN (registered trademark) BLACK S0084, PALIOGEN (registered trademark) K0084, PALIOGEN (registered trademark) L0086, PALIOGEN (registered trademark) K0086, PALIOGEN (registered trademark) EH0788, PALIOGEN (registered trademark) FK4281, and Lumogen Black K 0087, all manufactured by BASF. In one embodiment, Lumogen (registered trademark) Black K 0087 is used as the perylene black.

[0024] In the present invention, the film may contain 5 to 30 wt% of black pigment based on the total weight of the film. Preferably, the black pigment content is 5 wt% or more, 6 wt% or more, 7 wt% or more, 8 wt% or more, 9 wt% or more, 10 wt% or more, 11 wt% or more, 12 wt% or more, 13 wt% or more, or 14 wt% or more, with the upper limit being 30 wt% or less, 29 wt% or less, 28 wt% or less, 27 wt% or less, 26 wt% or less, 25 wt% or less, 24 wt% or less, 23 wt% or less, 22 wt% or less, 21 wt% or less, 20 wt% or less, 19 wt% or less, 18 wt% or less, or 17 wt% or less. If the black pigment content in the film is less than 5 wt%, light transmittance will be high, while if it exceeds 30 wt%, dispersibility and physical properties of the film will be reduced.

[0025] In the present invention, the film may contain 3 to 15% by weight of bituminous coal and 2 to 15% by weight of perylene black, based on the total weight of the film.

[0026] For example, the bituminous coal may be present in an amount of 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, or 6.5% by weight or more, with an upper limit of 10% by weight or less, 9% by weight or less, 8% by weight or less, or 7% by weight or less. If more than 15% by weight of bituminous coal is used, it is not effective in reducing permeability.

[0027] In one embodiment, perylene black may be present in an amount of 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, with an upper limit of 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. If the amount present is less than 2% by weight, it is not effective in reducing transmittance.

[0028] The present invention can maintain lower gloss, transmittance, dielectric constant, and dielectric loss factor by including black pigments including bituminous coal and perylene black.

[0029] In the present invention, the bituminous coal has an average particle size (D 50 The average particle size (D ) of the bituminous coal may be 0.5 to 10 μm, preferably 1 to 8 μm, and more preferably 2 to 5 μm. 10 ) is 0.5 to 2 μm, and the average particle size (D 90 The average particle size of the bituminous coal may be 3 to 7 μm. The average particle size of the bituminous coal may mean the average particle size after milling. 50 If the range of the particle diameter exceeds 10 μm, the surface properties of the film may be damaged, or the dispersibility and mechanical properties of the film may be deteriorated.

[0030] In the present invention, the perylene black has an average particle size (D 50 The average particle size (D) may be 100 nm to 1,200 nm, specifically 200 nm to 1,000 nm, and more specifically 300 nm to 900 nm. 50 If the average particle diameter (D) of the perylene black exceeds 1200 nm, the surface properties of the film may be damaged, or the dispersibility and mechanical properties of the film may be deteriorated. 10 ) is 100 to 400 nm, and the average particle size (D 90 ) may be 500 to 2000 nm. The average particle size of perylene black may mean the average particle size after milling.

[0031] The present invention realizes a black polyimide film with low gloss, transparency, dielectric constant and dielectric loss factor by adjusting the particle size of the black pigment to an appropriate size through milling.

[0032] In the present invention, the dianhydride monomer is selected from the group consisting of pyromellitic dianhydride (PMDA), oxydiphthalic dianhydride (ODPA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA), diphenylsulfone-3,4,3',4'-tetracarboxylic dianhydride (DSDA), bis(3,4-dicarboxyphenyl)sulfide dianhydride, 2,2-bis(3,4-dicarboxyphenyl)sulfide dianhydride, and 2,2-bis(3,4-dicarboxyphenyl)sulfide 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-phenylenebis(trimeric monoester acid anhydride), p-biphenylenebis(trimeric Monoester acid anhydride), m-terphenyl-3,4,3',4'-tetracarboxylic dianhydride, p-terphenyl-3,4,3',4'-tetracarboxylic dianhydride, 1,3-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)biphenyl dianhydride, 2,2-bis[(3,4-dicarboxyphenoxy)phenyl]propane dianhydride The dianhydride may be one or more selected from the group consisting of 2,3,6,7-naphthalenetetracarboxylic dianhydride (BPADA), 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, and 4,4'-(2,2-hexafluoroisopropylidene)diphthalic dianhydride, and specifically, pyromellitic dianhydride (PMDA), oxydiphthalic dianhydride (ODPA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3,3',It may be one or more selected from the group consisting of 4'-biphenyltetracarboxylic dianhydride (a-BPDA) and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA), and more specifically, it may be one or more selected from the group consisting of pyromellitic dianhydride (PMDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA) and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA).

[0033] In addition, the diamine monomer may be paraphenylenediamine (PPD), metaphenylenediamine, 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, 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, 3,4'-diaminodiphenyl ether, 4,4 '-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, 4,4'-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-phenyl)phenoxybenzophenone, 3,3'-diamino-4,4'-di(4-phenylphenoxy)benzophenone, 1,3-bis(3-aminophenylsulfide)benzene, 1,3-bis(4-aminophenylsulfide)benzene benzene, 1,4-bis(4-aminophenylsulfide)benzene, 1,3-bis(3-aminophenylsulfone)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 oxy)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] sulfone, bis[3-(4-aminophenoxy)phenyl] sulfone, bis[4-(3-aminophenoxy)phenyl] sulfone, bis[4-(4-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-(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, and specifically, paraphenylenediamine (PPD), 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine), 4,4'-oxydianiline (ODA), and 1,The compound may be one or more selected from the group consisting of 3-bis(4-aminophenoxy)benzene (TPE-R), more specifically, paraphenylenediamine (PPD) and 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine).

[0034] In one embodiment, the polyamic acid comprises, as polymerized units, a mixture of dianhydride monomers including pyromellitic dianhydride (PMDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA), and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA), and diamine monomers including paraphenylenediamine (PPD) and 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine).

[0035] Here, the pyromellitic dianhydride (PMDA) may be contained in a ratio of 20 mol% or more to 80 mol% or less of the total dianhydride monomer components, and 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. The upper limit of the ratio 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.

[0036] Furthermore, 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) may be contained in a ratio of 10 mol% or more to 50 mol% or less of the total dianhydride monomer components, and 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. The upper limit of the ratio 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.

[0037] Furthermore, 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA) or 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA) may be contained in a ratio of 10 mol% or more to 50 mol% or less of the total dianhydride monomer components, and 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, or 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, and the upper limit of the ratio 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.

[0038] In the present invention, the polyamic acid may contain dianhydride components, including pyromellitic dianhydride (PMDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA), and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA), in an amount of 100 mol % in total, and the content of the components may be appropriately adjusted.

[0039] In one embodiment, the dianhydride monomer may include 20 to 80 mol% of pyromellitic dianhydride (PMDA), 10 to 50 mol% of 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA) or 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA), and 10 to 50 mol% of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA).

[0040] Furthermore, paraphenylenediamine (PPD) may be contained in a ratio of 10 mol% or more to 80 mol% or less of the total diamine monomer components, and 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, or 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, and the upper limit of the ratio 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.

[0041] In addition, 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine) may be contained in a ratio of 20 mol% or more to 90 mol% or less of the total diamine monomer components, and 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, and the upper limit of the ratio is 90 mol% or less, 88 mol% or less. or less, 86 mol% or less, 84 mol% or less, 82 mol% or less, 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, 58 mol% or less, 56 mol% or less, 54 mol% or less, 52 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, or 35 mol% or less.

[0042] In the present invention, the polyamic acid may be appropriately adjusted in content of each component within a range in which the total of diamine monomer components including paraphenylenediamine (PPD) and 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine) is 100 mol %.

[0043] In one embodiment, the diamine monomer comprises 10 to 80 mol % of paraphenylenediamine (PPD) and 20 to 90 mol % of 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine).

[0044] In the present invention, the molar ratio of the diamine monomer to the dianhydride monomer may be 0.5 to 2 equivalents. Specifically, the molar ratio may be 0.8 to 1.5 equivalents. If the molar ratio is less than 0.5 equivalents or more than 2 equivalents, the molecular weight of the polyimide finally formed will be very small, which will result in a significant deterioration in the physical and chemical properties of the polyimide.

[0045] The black polyimide film according to the present invention may have a thickness of 3 to 100 μm, specifically 4 to 90 μm, more specifically 5 to 80 μm, and even more specifically 5.5 to 50 μm. The thickness of the film is not particularly limited as long as it is within a range that allows flexible coating, and the thickness can be adjusted taking into consideration mechanical strength, handleability, productivity, etc.

[0046] The black polyimide film of the present invention has a transmittance in the visible light region of 0.2% or less, a gloss (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.

[0047] In addition, the black polyimide film of the present invention has a transmittance in the visible light region of 0.1% or less, a gloss (60°) of 40 or less, a dielectric constant (Dk) of 3.7 or less, and a dielectric loss factor (Df) of 0.01 or less.

[0048] The black polyimide film of the present invention may simultaneously satisfy the following conditions: transmittance in the visible light region of 0.2% or less, gloss (60°) of 50 or less, dielectric constant (Dk) of 4.0 or less, and dielectric loss factor (Df) of 0.01 or less.

[0049] The black polyimide film of the present invention may simultaneously satisfy the following conditions: transmittance in the visible light region of 0.1% or less, gloss (60°) of 40 or less, dielectric constant (Dk) of 3.7 or less, and dielectric loss factor (Df) of 0.01 or less.

[0050] For example, the black polyimide film according to the present invention may have a dielectric constant of 4.0 or less at 10 GHz, preferably 3.9 or less, and more preferably 3.7 or less, with the lower limit being at least 3.0 or more. Considering that the engineering properties of polyimide films are at the highest level, this shows that the black polyimide film exhibits an ideal dielectric constant as an insulator.

[0051] Furthermore, for example, the black polyimide film according to the present invention may have a dielectric loss factor (Df) of 0.01 or less at 10 GHz, preferably 0.0099 or less, with a lower limit of at least 0.005. "Dielectric loss factor" refers to the force dissipated by a dielectric (or insulator) when molecular friction interferes with molecular motion caused by an alternating electric field. The value of the dielectric loss factor is generally used as an index indicating the ease of charge loss (dielectric loss). The higher the dielectric loss factor, the easier it is to lose charge, and conversely, the lower the dielectric loss factor, the more difficult it is to lose charge. In other words, since the dielectric loss factor is a measure of power loss, the lower the dielectric loss factor, the more mitigated signal transmission delays caused by power loss can be, allowing for faster communication speeds to be maintained.

[0052] Therefore, the polyimide film of the present invention has the advantage that it can easily maintain insulation even in electronic devices for high-speed transmission that operate at frequencies in the giga (GIGA) range, for example, at high frequencies of 10 GHz or higher.

[0053] In addition, the black polyimide film according to the present invention may have a transmittance of 0.2% or less, preferably 0.10 or less, for example, which is considered to have suitable physical properties for use as a coverlay.

[0054] Furthermore, the gloss (60°) of the black polyimide film according to the present invention may be 50 or less, preferably 45 or less, more preferably 40 or less, and even more preferably 37 or less. If the gloss exceeds 50, there may be problems such as a decrease in visual aesthetics and a decrease in coating function.

[0055] Therefore, polyimide films that satisfy all the requirements for dielectric constant, dielectric loss factor, glossiness, and transmittance can be used as insulating films for coverlays. Even when the manufactured coverlay is used as an electrical signal transmission circuit that transmits signals at high frequencies of 10 GHz or more, its insulating stability can be ensured and signal transmission delays can be minimized.

[0056] The black polyimide film of the present invention simultaneously satisfies the following conditions: transmittance in the visible light region is 0.2% or less, gloss (60°) is 50 or less, dielectric constant (Dk) is 4.0 or less, and dielectric loss factor (Df) is 0.01 or less. This is a novel black polyimide film that has not been known before.

[0057] Method for producing the black polyimide film of the present invention The present invention provides the following method for producing a black polyimide film.

[0058] (1) polymerizing a polyamic acid solution from one or more dianhydride monomers and one or more diamine monomers; (2) mixing the polyamic acid solution with a black pigment including bituminous coal and perylene black to prepare a polyimide precursor composition; and (3) A step of forming a film of the polyimide precursor composition on a support and imidizing it by heat treatment.

[0059] In the method for producing the black polyimide film, the "dianhydride monomer" and the "diamine monomer" are as described above, and the black polyimide film of the present invention can be produced by any method generally used for producing polyimide films.

[0060] In one embodiment, in step (1), the dianhydride and diamine are reacted in an organic solvent to obtain a polyamic acid solution. The solvent is not particularly limited as long as it can dissolve the polyamic acid. For example, the solvent may be an aprotic polar solvent, preferably N-methylpyrrolidone (NMP), N,N'-dimethylformamide (DMF), N,N'-diethylformamide (DEF), N,N'-dimethylacetamide (DMAc), dimethylpropanamide (DMPA), N,N-diethylacetamide (685-91-6, DEAc), or 3-methoxy-N,N-dimethylpropanamide (53185-52-7, KJCMPA), either alone or in combination. Most preferably, N-methylpyrrolidone (NMP) is used.

[0061] In the present invention, the weight-average molecular weight of the polyamic acid solution of the present invention may be 100,000 g / mol to 300,000 g / mol. The lower limit of the weight-average molecular weight may be 100,000 g / mol, 120,000 g / mol, 150,000 g / mol, or 200,000 g / mol or more, and the upper limit of the weight-average molecular weight may be 300,000 g / mol, 280,000 g / mol, 270,000 g / mol, 260,000 g / mol, or 250,000 g / mol or less.

[0062] In the present invention, the solids content is defined as the weight of monomers added to the entire polyamic acid solution when substantially equimolar amounts of diamine and dianhydride are added. The solids content of the polyamic acid solution may be 5 to 30 wt%. The lower limit of the solids content may be 5 wt%, 8 wt%, 9 wt%, 10 wt%, 15 wt%, 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, or 29 wt% or more, and the upper limit of the solids content may be 29 wt%, 27 wt%, 25 wt%, 23 wt%, 21 wt%, 20 wt%, 19 wt%, or 18 wt% or less. Adjusting the solids content of the polyamic acid composition can control viscosity increases and shorten the process time during the curing process.

[0063] In the present invention, the polyamic acid solution is heated at a temperature of 23° C. for 1 s. -1 The viscosity measured under the shear rate conditions may be in the range of 20,000 to 400,000 cP. For example, the upper limit may be 400,000 cP, 350,000 cP, 300,000 cP, or 250,000 cP. The lower limit is not particularly limited, but may be 20,000 cP, 30,000 cP, 40,000 cP, 50,000 cP, 60,000 cP, or 80,000 cP or more. The viscosity may be measured, for example, using a Rheostress 600 manufactured by Haake under the conditions of a shear rate of 1 / s, a temperature of 23°C, and a plate gap of 1 mm. By adjusting the viscosity range, the present invention can provide a precursor composition with excellent processability.

[0064] In step (2), the bituminous coal and perylene black contained in the polyimide precursor composition are milled in a milling process to adjust the particle size, thereby increasing the degree of dispersion, allowing them to be uniformly mixed with the polyamic acid solution, and reducing the gloss, transmittance, dielectric constant, and dielectric loss factor.

[0065] Therefore, before the step (2), the powder is milled using a milling machine to obtain an average particle size (D 50 ) of 0.5 to 10 μm and bituminous coal with an average particle size (D 50 ) can be further carried out to produce perylene black having a particle size of 30 to 1000 nm.

[0066] In one embodiment, the milling step can produce bituminous coal and / or perylene black having particle sizes in the aforementioned ranges by a bead mill using beads having a particle size of 1.0 to 2.0 mm. The milling treatment can be performed on bituminous coal and perylene black individually, or on bituminous coal and perylene black together. The stirring speed and milling time during the milling step are not particularly limited, as they can be adjusted appropriately depending on the desired particle size. Furthermore, by performing milling using a bead mill using beads having a particle size of 0.8 to 1.5 mm, bituminous coal and / or perylene black having particle sizes in the aforementioned ranges can be produced.

[0067] In step (2), the black pigment is prepared by dispersing bituminous coal and perylene black in an organic solvent. The organic solvent may be one or more selected from the group consisting of N-methylformamide, N,N'-dimethylformamide (DMF), N-methylformanilide, N,N'-dimethylacetamide (DMAC), N-methyl-pyrrolidone (NMP), propylene glycol methyl ether acetate (PGMEA), ethyl glycol acetate, propylene glycol monomethyl ether acetate, dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether, and acetylacetone, and preferably one or more selected from the group consisting of N,N'-dimethylformamide (DMF), N,N'-dimethylacetamide (DMAC), N-methyl-pyrrolidone (NMP), and propylene glycol methyl ether acetate (PGMEA).

[0068] In the present invention, in step (3), the polyimide precursor composition prepared in step (2) is cast on a support, dried to form a gel film, and then the gel film is imidized to form a black polyimide film.

[0069] The gel film is formed by casting the polyimide precursor composition in the form of a film on a support such as an aluminum foil, an endless stainless steel belt, or a stainless steel drum, and then drying the precursor composition on the support at a variable temperature ranging from 50°C to 200°C, particularly from 80°C to 150°C.

[0070] The imidization can be carried out by heat treatment, which can be carried out at a temperature variable within the range of 50°C to 500°C, specifically 150°C to 500°C, thereby removing residual water, residual solvent, etc., and imidizing almost all of the remaining amic acid groups, thereby producing the black polyimide film of the present invention. In some cases, the polyimide film obtained as described above may be heat-finished at a temperature of 400°C to 650°C for 5 to 400 seconds to further harden the polyimide film, and this may be carried out under a predetermined tension in order to relieve internal stress that may remain in the obtained polyimide film.

[0071] The present invention provides a coverlay including the black polyimide film and an electronic device for high-speed transmission including the coverlay. [Effects of the Invention]

[0072] The black polyimide film of the present invention contains a black pigment in combination with bituminous coal and black perylene, and therefore has excellent optical properties such as low gloss and low transmittance, as well as low dielectric constant and dielectric loss factor, resulting in excellent low dielectric properties. DETAILED DESCRIPTION OF THE INVENTION

[0073] Examples are presented below to aid in understanding the present invention. The following examples are provided to facilitate understanding of the present invention, and are not intended to limit the scope of the present invention.

[0074] <Example> Example 1: Preparation of polyimide precursor composition

[0075] Example 1-1 For the polyamic acid solution polymerization process, 408.62 g of dimethylformamide (DMF) was added to a 500 mL reactor under a nitrogen atmosphere. After setting the temperature to 25°C, diamine monomers PPD (66 mol%) and m-tolidine (34 mol%) were added and stirred for 30 minutes to confirm that the monomers were dissolved. Then, dianhydride monomers PMDA (35 mol%), BTDA (33 mol%), and BPDA (32 mol%) were added and stirred until the viscosity no longer changed, yielding a polyamic acid solution.

[0076] The polyamic acid solution was mixed with black pigments, including bituminous coal (6.6 wt%) and perylene black (3.5 wt%) dispersed in an organic solvent, to prepare a polyimide precursor composition, with the black pigment content being 10.1 wt% in total.

[0077] Example 1-2 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 wt%) and perylene black (4.5 wt%) was used instead of the black pigment containing bituminous coal (6.6 wt%) and perylene black (3.5 wt%) used in Example 1-1. The black pigment was contained in the polyimide precursor composition in a total amount of 11.1 wt%.

[0078] Examples 1-3 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 wt%) and perylene black (5.5 wt%) was used instead of the black pigment containing bituminous coal (6.6 wt%) and perylene black (3.5 wt%) used in Example 1-1. The black pigment was contained in the polyimide precursor composition in a total amount of 12.1 wt%.

[0079] Examples 1-4 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 wt%) and perylene black (6.5 wt%) was used instead of the black pigment containing bituminous coal (6.6 wt%) and perylene black (3.5 wt%) used in Example 1-1. The black pigment was contained in the polyimide precursor composition in a total amount of 13.1 wt%.

[0080] The components and contents of the polyimide precursor compositions prepared in Examples 1-1 to 1-4 are summarized in Table 1 below (wherein the weight % of the black pigment means the content in the polyimide precursor composition).

[0081] [Table 1]

[0082] Comparative Example 1: Preparation of polyimide precursor composition

[0083] Comparative Example 1-1 (without black pigment) For the polyamic acid solution polymerization process, 408.62 g of dimethylformamide (DMF) was added to a 500 mL reactor under a nitrogen atmosphere. After setting the temperature to 25°C, diamine monomers PPD (66 mol%) and m-tolidine (34 mol%) were added and stirred for 30 minutes to confirm that the monomers were dissolved. Then, dianhydride monomers PMDA (35 mol%), BTDA (33 mol%), and BPDA (32 mol%) were added and stirred until the viscosity no longer changed, yielding a polyamic acid solution.

[0084] Comparative Example 1-2 (Containing only bituminous coal as black pigment) 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 wt%) was used instead of the black pigment containing bituminous coal (6.6 wt%) and perylene black (3.5 wt%) in Example 1-1. The black pigment was contained in a total amount of 6.6 wt% in the polyimide precursor composition.

[0085] Comparative Example 1-3 (Containing bituminous coal and carbon black as black pigments) 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 wt%) and carbon black (2.5 wt%) was used instead of the black pigment containing bituminous coal (6.6 wt%) and perylene black (3.5 wt%) used in Example 1-1. The black pigment was contained in a total amount of 9.1 wt% in the polyimide precursor composition.

[0086] Comparative Example 1-4 (Containing only perylene black as black pigment) A polyimide precursor composition was prepared in the same manner as in Example 1-1, except that a black pigment containing only perylene black (2.5 wt%) was used instead of the black pigment containing bituminous coal (6.6 wt%) and perylene black (3.5 wt%) in Example 1-1. The black pigment was contained in the polyimide precursor composition in a total amount of 2.5 wt%.

[0087] Comparative Example 1-5 (Containing only perylene black as black pigment) A polyimide precursor composition was prepared in the same manner as in Example 1-1, except that a black pigment containing only perylene black (4.5 wt%) was used instead of the black pigment containing bituminous coal (6.6 wt%) and perylene black (3.5 wt%) in Example 1-1. The black pigment was contained in the polyimide precursor composition in a total amount of 4.5 wt%.

[0088] The components and contents of the polyimide precursor compositions prepared in Comparative Examples 1-1 to 1-5 are summarized in Table 2 below.

[0089] [Table 2]

[0090] Example 2: Preparation of black polyimide film

[0091] Example 2-1 The polyimide precursor composition prepared in Example 1-1 was cast onto a SUS plate (100SA, Sandvik) at a thickness of 70 μm using a doctor blade and dried at temperatures ranging from 100 to 200°C. The film was then peeled off from the SUS plate, fixed to a pin frame, and transferred to a high-temperature tenter. The film was heated to 200 to 600°C in the high-temperature tenter, cooled to 25°C, and then separated from the pin frame to produce a 12.5±0.5 μm thick black polyimide film containing 6.6 wt% bituminous coal and 3.5 wt% perylene black based on the total weight of the polyimide film.

[0092] Example 2-2 In Example 2-1, a black polyimide film containing 6.6 wt % bituminous coal and 4.5 wt % perylene black, based on the total weight of the polyimide film, was prepared 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.

[0093] Example 2-3 In Example 2-1, a black polyimide film containing 6.6 wt % bituminous coal and 5.5 wt % perylene black, based on the total weight of the polyimide film, was prepared 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.

[0094] Examples 2-4 In Example 2-1, a black polyimide film containing 6.6 wt % bituminous coal and 6.5 wt % perylene black, based on the total weight of the polyimide film, was prepared in the same manner as in Example 2-1, except that the polyimide precursor composition prepared in Example 1-1 was replaced with the polyimide precursor composition prepared in Example 1-4.

[0095] Comparative Example 2: Preparation of black polyimide film

[0096] Comparative Example 2-1 (without black pigment) A polyimide film was prepared 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 contain a black pigment.

[0097] Comparative Example 2-2 (Containing only bituminous coal as black pigment) A black polyimide film containing 6.6 wt % bituminous coal based on the total weight of the polyimide film was prepared 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.

[0098] Comparative Example 2-3 (Containing bituminous coal and carbon black as black pigments) A black polyimide film containing 6.6 wt % bituminous coal and 2.5 wt % carbon black, based on the total weight of the polyimide film, was prepared 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.

[0099] Comparative Example 2-4 (Containing only perylene black as black pigment) A black polyimide film containing 2.5 wt % of perylene black based on the total weight of the polyimide film was prepared 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.

[0100] Comparative Example 2-5 (Containing only perylene black as black pigment) A black polyimide film containing 4.5 wt % of perylene black based on the total weight of the polyimide film was prepared in the same manner as in Example 2-1, except that the polyimide precursor composition prepared in Comparative Example 1-5 was used instead of the polyimide precursor composition of Example 1-1.

[0101] <Experimental Example>

[0102] Experimental Example 1: Evaluation of gloss The gloss was measured at an angle of 60° using a gloss measuring device (Model: PG-IIM, Manufacturer: NIPPON DENSHOKU) according to ASTM D523 method, and the results are shown in Table 3.

[0103] Experimental Example 2: Evaluation of transmittance The transmittance was measured in the visible light region using a transmittance measuring device (model: COLORQUESETXE, manufacturer: HunterLab) according to the ASTM D1003 method, and the results are shown in Table 3.

[0104] Experimental Example 3: Evaluation of dielectric constant (Dk) The dielectric constant was measured at 10 GHz using a Keysight SPDR measuring instrument, and the results are shown in Table 3.

[0105] Experimental Example 4. Dielectric loss factor (Df) The dielectric loss factor (Df) was measured using an Agilent 4294A resistance meter after leaving the flexible metal foil-clad laminate for 72 hours. The results are shown in Table 3.

[0106] [Table 3]

[0107] Referring to Table 3, the black polyimide film of the present invention simultaneously satisfies the requirements of transmittance of 0.1% or less, glossiness of 50 or less, dielectric constant of 4.0 or less, and dielectric loss factor of 0.01 or less.

[0108] However, Comparative Example 2-1, which does not contain a black pigment, and Comparative Examples 2-4 and 2-5, which contain only perylene black as a black pigment, have very high transmittance and gloss, while Comparative Example 2-2, which contains only bituminous coal as a black pigment, has a very high transmittance of over 2%.

[0109] Furthermore, Comparative Example 2-3, which contains bituminous coal and carbon black as black pigments, has a significantly high dielectric constant and dielectric loss factor of 4.61 and 0.03082, respectively.

[0110] This specification omits detailed descriptions of content that can be fully recognized and inferred by a person having ordinary skill in the art of the present invention, and various modifications are possible within the scope of the specific examples described in this specification without changing the technical idea or essential configuration of the present invention. Therefore, the present invention can be implemented in ways different from those specifically explained and exemplified in this specification, and this is something that can be understood by a person having ordinary skill in the art of the present invention.

Claims

1. A black polyimide film obtained by imidizing a polyamic acid obtained from a dianhydride monomer and a diamine monomer, The black polyimide film contains black pigments including bituminous coal and perylene black.

2. 2. The black polyimide film of claim 1, wherein the film comprises 3 to 15 wt. % bituminous coal and 2 to 15 wt. % perylene black, based on the total weight of the film.

3. 2. The black polyimide film of claim 1, wherein the film comprises 5 to 10 wt. % bituminous coal and 3 to 10 wt. % perylene black, based on the total weight of the film.

4. The bituminous coal has an average particle size (D ５０ 2. The black polyimide film according to claim 1, wherein the thickness is 0.5 to 10 μm.

5. The perylene black has an average particle size (D ５０ 2. The black polyimide film according to claim 1, wherein the average particle diameter is 100 to 1200 nm.

6. The dianhydride monomer may be pyromellitic dianhydride (PMDA), oxydiphthalic dianhydride (ODPA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA), diphenylsulfone-3,4,3',4'-tetracarboxylic dianhydride (DSDA), bis(3,4-dicarboxyphenyl)sulfide dianhydride, or the like. ide, 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-phenylenebis(trimellitic Monoester acid anhydride), p-biphenylene bis(trimeric monoester acid anhydride), m-terphenyl-3,4,3',4'-tetracarboxylic dianhydride, p-terphenyl-3,4,3',4'-tetracarboxylic dianhydride, 1,3-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(3,4- 2. The black polyimide film according to claim 1, wherein the dianhydride is at least one selected from the group consisting of 2,2-bis[(3,4-dicarboxyphenoxy)biphenyl]dianhydride, 2,2-bis[(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (BPADA), 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, and 4,4'-(2,2-hexafluoroisopropylidene)diphthalic acid dianhydride.

7. The diamine monomers include paraphenylenediamine (PPD), metaphenylenediamine, 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, 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, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether 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, 4,4' -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-phenyl)phenoxybenzophenone, 3,3'-diamino-4,4'-di(4-phenylphenoxy)benzophenone, 1,3-bis(3-aminophenylsulfide)benzene, 1,3-bis(4-aminophenylsulfide)benzene, 1,4-bis(4 -aminophenylsulfide)benzene, 1,3-bis(3-aminophenylsulfone)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]sulfide, bis[3-(4-aminophenoxy)phenyl]sulfide, bis[4-(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[4-(4-aminophenoxy)phenyl]sulfone, bis[3-(3-aminophenoxy)phenyl]sulfone 2,2-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]methane, bis[4-(3-aminophenoxy)phenyl]methane, bis[4-(4-aminophenoxy)phenyl]methane 2. The black polyimide film according to claim 1, wherein the bis(3-(4-aminophenoxy)phenyl)-1,1,1,3,3,3-hexafluoropropane is at least one selected from the group consisting of 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 dianhydride monomer is at least one selected from the group consisting of pyromellitic dianhydride (PMDA), oxydiphthalic dianhydride (ODPA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA), and 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA); 2. The black polyimide film according to claim 1, wherein the diamine monomer is at least one selected from the group consisting of paraphenylenediamine (PPD), 2,2'-dimethyl-4,4'-diaminobiphenyl (m-tolidine), 4,4'-oxydianiline (ODA), and 1,3-bis(4-aminophenoxy)benzene (TPE-R).

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

10. 2. The black polyimide film according to claim 1, wherein the thickness of the film is 5 to 100 μm.

11. The black polyimide film is The transmittance in the visible light region is 0.2% or less, The gloss (60°) is 50 or less, The dielectric constant (Dk) is 4.0 or less, 2. The black polyimide film according to claim 1, having a dielectric loss factor (Df) of 0.01 or less.

12. (1) polymerizing a polyamic acid solution from one or more dianhydride monomers and one or more diamine monomers; (2) mixing the polyamic acid solution with bituminous coal and a black pigment including perylene black to prepare a polyimide precursor composition; (3) forming a film of the polyimide precursor composition on a support and heat-treating the film to imidize it; Manufacturing method of black polyimide film.

13. Before the step (2), the powder is milled using a milling machine to have an average particle size (D ５０ ) is 0.5 to 10 μm and bituminous coal having an average particle size (D ５０ 13. The method for producing a black polyimide film according to claim 12, further comprising the steps of:

14. 13. The method for producing a black polyimide film according to claim 12, wherein in step (2), the black pigment is a dispersion of bituminous coal and perylene black in an organic solvent.

15. 15. The method for producing a black polyimide film 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-methyl-pyrrolidone (NMP), propylene glycol methyl ether acetate (PGMEA), ethyl glycol acetate, propylene glycol monomethyl ether acetate, dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether, and acetylacetone.

16. A coverlay comprising the black polyimide film of any one of claims 1 to 11.

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

Images