TW201423769A - Process for manufacturing conductive polyimide film - Google Patents

Abstract

According to the present invention, a conductive polyimide film which exhibits excellent film strength and a desired resistivity can be manufactured with good productivity by subjecting a coating to drying and imidization, said coating comprising (A) a polyamic acid obtained by reacting a tetracarboxylic dianhydride component that contains pyromellitic dianhydride with a diamine component that contains a dimamine having three or more aromatic rings in one molecule, (B) a conductivity -imparting agent, and (C) an imidization accelerator.

Description

Method for producing conductive polyimide film

The present invention relates to a method of producing a conductive polyimide film.

Polyimine membranes have been put into practical use in a wide range of fields from aerospace to electronic materials based on high mechanical strength, heat resistance, chemical resistance and the like. Moreover, the conductive polyimide film which imparts conductivity to the polyimide film is useful as a substitute for the metal-based electronic material, and is particularly preferably used for an electrode material for an electric battery, an electromagnetic shielding material, a film for electrostatic adsorption, Antistatic agent, image forming device parts, electronic devices, and the like.

The conductive polyimide film is produced by the following steps.

(1) a step of casting a polyamic acid solution in which a conductivity-imparting agent is dispersed on a support to form a coating film, and (2) performing a sublimation, removal, and imidization of the solvent.

Previously, after dispersing carbon black in a polar organic solvent, tetracarboxylic dianhydride and a diamine component were added to react to form a polyaminic acid solution. Although the oxime was imidized, the dispersibility of carbon black was compared. Low, easy to cause the problem of carbon black condensation.

Therefore, for example, Patent Document 1 proposes dispersing a surfactant and carbon black in a polyphosphoric acid-diluted solution, and then adding a tetracarboxylic dianhydride and a diamine component to cause a reaction, thereby suppressing carbon black during polymerization. The method of agglomeration was carried out by thermal imidization in the examples to obtain a semiconductive polyimide lens.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2007-41214

The thermal imidization method has a tendency to be inferior in productivity because the time required for the above step (2) of producing the polyimide film is extremely long.

On the other hand, in the case of producing a conductive polyimide film by the chemical imidization method, there is a problem unique to the chemical oxime imidization method in which the carbon black re-agglomerates in the sulfiliation or drying step. There is a need for improvement that is suitable for the chemical imidization process.

Further, the film strength may be lowered due to the carbon black contained in the inside of the film. The decrease in the film strength not only causes a decrease in productivity, but also the durability as a substitute material for the metal-based electronic material is lowered, which is not preferable.

Accordingly, the present invention provides a method for producing a conductive polyimide film having excellent film strength and having a desired electrical resistivity with good productivity.

The inventors of the present invention have repeatedly studied in view of the above-mentioned contents, and as a result, the following findings have been found: when the chemical hydrazine imidization method is used, pyromellitic dianhydride is used as the tetracarboxylic dianhydride and contains three or more molecules. When a diamine compound is used as a diamine compound to produce a conductive polyimide film, it can be controlled to a desired low resistivity without being inferior to the thermal imidization method, so the drying time can be short. A conductive polyimide film is produced with good productivity. Further, it was found that the obtained conductive polyimide film also has film strength, thereby completing the present invention.

That is, the present invention relates to a method for producing a conductive polyimide film, which is characterized in that it is a method for producing a conductive polyimide film containing a conductive agent and a polyimide resin, and will contain A) a tetracarboxylic dianhydride component containing pyromellitic dianhydride and a diamine compound component containing a diamine having three or more aromatic rings in one molecule The coating film obtained by the reaction is dried, and the film of the (B) conductivity imparting agent and the (C) quinone imidization accelerator are dried and yttrium imidized.

In the method for producing a conductive polyimide film of the present invention, it is preferred that the diamine having three or more aromatic rings in one molecule has one of the following general formulas (1) to (6) in the molecule. The structure represented.

(About the aromatic ring in the general formulae (1) to (6), a part thereof may be substituted by a halogen, an alkyl group, an alkyl halide, an alkoxy group, a phenyl group or a phenoxy group)

In the method for producing a conductive polyimide film of the present invention, preferably the above molecule The diamine having three or more aromatic rings in its own is a compound represented by the following formula (7).

(In the formula (7), Ar represents an aromatic ring; and X is any one selected from the group consisting of O, a direct bond, CO, C(CH ₃ ) ₂ , S, and SO ₂ , and may be in one molecule. All of the same, may be partially or completely different; n≧2; and, with respect to Ar, a part thereof may also be substituted by halogen, alkyl, halogenated alkyl, alkoxy, phenyl, or phenoxy group in one molecule. Can be all the same, or some or all of them different)

In the method for producing a conductive polyimide film of the present invention, it is preferred that the diamine having three or more aromatic rings in one molecule is selected from the compounds represented by the following chemical formulas (8) to (16). At least one of the groups.

In the method for producing a conductive polyimide film of the present invention, it is preferable that the content of the pyromellitic dianhydride is 50 to 100 mol% in 100 mol% of the tetracarboxylic dianhydride component, and/ Or the content of the diamine having three or more aromatic rings in the above molecule is 50 to 100 mol% in 100 mol% of the diamine compound component.

In the method for producing a conductive polyimide film of the present invention, it is preferable that the (B) conductivity imparting agent contains carbon conductive particles.

In the method for producing a conductive polyimide film of the present invention, the content of the (B) conductive agent is preferably from 1 to 50 parts by weight based on 100 parts by weight of the (A) polyamine.

In the method for producing a conductive polyimide film of the present invention, it is preferred that the (C) quinone imidization accelerator contains a catalyst and a chemical dehydrating agent.

In the method for producing a conductive polyimide film according to the present invention, it is preferred that the amount of the catalyst used in the (C) quinone imidization accelerator is relative to the proline in the (A) poly-proline. Mohr is in the range of 0.1 to 4.0 molar equivalents.

In the method for producing a conductive polyimide film of the present invention, the above (C) The amount of the chemical dehydrating agent to be used in the amination promoter is in the range of 1.0 to 5.0 mol equivalents based on 1 mole of the valine acid in the above (A) polyglycolic acid.

In the method for producing a conductive polyimide film of the present invention, the thickness of the conductive polyimide film may be in the range of 1 to 100 μm.

In the method for producing a conductive polyimide film of the present invention, it is preferred that the conductive polyimide film has a volume resistivity in a thickness direction of 1.0 × 10 ^-1 to 1.0 × 10 ² Ωcm, and / or the surface resistivity is in the range of 1.0 × 10 ¹ ~ 1.0 × 10 ⁴ Ω / □.

In the method for producing a conductive polyimide film of the present invention, it is preferred that the conductive polyimide film has a tear propagation resistance (R, unit: g/mm) in a range of from 120 to 300.

According to the production method of the present invention, the film strength can be excellent, and the electrical resistivity of the obtained conductive polyimide film can be adjusted to be as desired in the same manner as the thermal hydrazine imidization method. In the present production method, since the drying time is sufficient for a short period of time, it is possible to reduce the size of the apparatus or increase the operation speed, and it is excellent in productivity.

An embodiment of the present invention will be described below, but the present invention is not limited thereto.

The polylysine used in the process of the present invention is obtained by reacting a diamine compound component with a tetracarboxylic dianhydride component, and it is necessary to use pyromellitic dianhydride as the tetracarboxylic dianhydride. The component is a diamine compound component which has a diamine having three or more aromatic rings in one molecule.

As the tetracarboxylic dianhydride component, in addition to pyromellitic dianhydride, other tetracarboxylic dianhydride may be used in combination. Specific examples thereof include 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, and 1,2,5,6-naphthalene. Tetracarboxylic dianhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 4,4'-oxygen Phthalic phthalic anhydride, 2,2-double (3,4-dicarboxyphenyl)propane dianhydride, 3,4,9,10-decanetetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)propane dianhydride, 1,1-double ( 2,3-dicarboxyphenyl)ethane dianhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, double (3,4-dicarboxyphenyl)ethane dianhydride, oxydiphthalic dianhydride, bis(3,4-dicarboxyphenyl)ruthenium anhydride, p-phenylene bis(trimellitic acid) Ester anhydride), ethyl bis(trimellitic acid monoester anhydride), bisphenol A bis (trimellitic acid monoester anhydride) and a part thereof are halogen, alkyl, halogenated alkyl, alkoxy, a substituted derivative such as a phenyl group or a phenoxy group.

Among these tetracarboxylic dianhydrides, 3,3',4,4'-benzenetetracarboxylic dianhydride, 3,3', 4, 4 can be preferably used in combination from the viewpoint of industrial availability. '-benzophenone tetracarboxylic dianhydride, 4,4'-oxyphthalic acid dianhydride.

These may be used alone or in combination of two or more.

The diamine compound component is characterized by comprising a diamine having three or more aromatic rings in one molecule.

In the present invention, the term "aromatic ring" means a cyclic unsaturated structure of an organic compound. In the cyclic unsaturated structure of the organic compound, there are a monocyclic aromatic ring of four to seven member rings, and a polycyclic aromatic ring formed by condensation of a plurality of single rings. In the present invention, preferred examples of the aromatic ring include benzene of a monocyclic aromatic ring, naphthalene of a polycyclic aromatic ring, and hydrazine, and particularly preferably benzene. In the case of a diamine having such an aromatic ring, the synthesis of polyimine can be carried out smoothly.

The diamine used in the present invention has three or more aromatic rings in one molecule, and the upper limit of the number of aromatic rings per molecule is preferably 10, more preferably 6. If it is more than 10, the synthesis of polyimine does not proceed smoothly. If it is less than 3, it will not exhibit the required resistivity.

It is preferable that the diamine having three or more aromatic rings in one molecule contains at least a structure represented by any one of the following general formulae (1) to (6) in the molecule.

Further, one of the aromatic rings of the above formulas (1) to (6) may be substituted by a halogen, an alkyl group, an alkyl halide, an alkoxy group, a phenyl group or a phenoxy group.

When the structure represented by any one of the above formulas (1) to (6) is contained, the strength of the finally obtained film is excellent.

The diamine having any one of the structures represented by the above formulas (1) to (6) and having three or more aromatic rings in one molecule may be a linear type or a branched type. A compound represented by the following formula (7) is preferred.

In the above formula (7), Ar represents an aromatic ring. X is any one selected from the group consisting of O, a direct bond, CO, C(CH ₃ ) ₂ , S, and SO ₂ , and may be all the same in one molecule, or may be partially or entirely different. n≧2.

Further, a part of Ar may be substituted by a halogen, an alkyl group, an alkyl halide, an alkoxy group, a phenyl group or a phenoxy group, and may be all the same in one molecule, or may be partially or wholly different.

The preferred diamine having three or more aromatic rings in one molecule may, for example, be a compound represented by the following chemical formulas (8) to (16) and derivatives thereof.

Here, as a derivative, one of the structural formulae of the above formulas (8) to (16) may be substituted with a halogen, an alkyl group, an alkyl halide, an alkoxy group, a phenyl group, a phenoxy group or the like.

In addition to the above compounds, bis{4-(4-aminophenoxy)phenyl}anthracene, bis{4-(3-aminophenoxy)phenyl}anthracene or the like can be preferably used.

The diamine having three or more aromatic rings in one molecule may be used singly or in plural.

In the diamine compound component, a diamine having one or two aromatic rings in one molecule can be used in combination insofar as it does not impair the effects of the present invention. Specific examples thereof include 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylisopropane, 4,4′-diaminodiphenylmethane, and benzidine. 3,3'-dichlorobenzidine, 3,3'-dimethylbenzidine, 2,2'-dimethylbenzidine, 3,3'-dimethoxybenzidine, 2,2'-di Methoxybenzidine, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenylanthracene, 4,4'-diaminodiphenylanthracene, 3,3'- Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 4,4'-diaminodiphenyldiethyldecane, 4,4'-di Aminodiphenylnonane, 4,4'-diaminodiphenylethylphosphine oxide, 4,4'-diaminodiphenyl N-methylamine, 4,4'-diaminodiphenyl N-phenylamine, 1,4-diaminobenzene (p-phenylenediamine), 1,3-diaminobenzene, 1,2-diaminobenzene, 3,3'-diaminodiphenyl A ketone, a 4,4'-diaminobenzophenone, and a derivative in which one of them is substituted with a halogen, an alkyl group, an alkyl halide, an alkoxy group, a phenyl group, a phenoxy group or the like.

Among these diamines, it is preferably used in combination from the viewpoint of being industrially easy to obtain. 4,4'-Diaminodiphenyl ether, 4,4'-diaminodiphenylisopropane, 1,4-diaminobenzene.

In the present invention, the content of the pyromellitic dianhydride is not particularly limited, but from the viewpoint of obtaining a conductive polyimide film having excellent film strength and high conductivity, tetracarboxylic acid is preferred. The total amount of moles of the dianhydride component is from 50 to 100 mol%, more preferably from 70 to 100 mol%, in 100 mol%.

In the present invention, the content of the diamine having three or more aromatic rings in one molecule is not particularly limited, but from the viewpoint of obtaining a conductive polyimide film having excellent film strength and high conductivity, Preferably, the total mole number of the diamine compound component is from 50 to 100 mol%, more preferably from 70 to 100 mol%.

In the present invention, pyromellitic dianhydride or a diamine having three or more aromatic rings in one molecule is preferably the above-mentioned preferred content. When any of the above-mentioned preferred contents is used, it is easy to obtain a conductive polyimide film having excellent film strength and high conductivity. From the viewpoint of excellent film strength and electrical conductivity, it is more preferable that both of them are the above preferred contents.

The tetracarboxylic dianhydride and the diamine compound, which are substantially equal in molar amount, are usually dissolved in an organic solvent by using all methods known as polyamic acid, and stirred under controlled temperature conditions until The polymerization of the above tetracarboxylic dianhydride and the diamine compound is completed.

A preferred solvent for synthesizing the polyamic acid may be any solvent as long as it is a solvent for dissolving the polyamic acid, preferably a guanamine solvent, that is, N,N-dimethylformamide, N,N. - dimethylacetamide, N-methyl-2-pyrrolidone, etc., among which N,N-dimethylformamide and N,N-dimethylacetamide are particularly preferably used. These may be used singly or in combination of two or more.

The polyaminic acid solution is usually preferably obtained in a concentration of 5 to 35 wt%, more preferably 10 to 30 wt%. When the concentration is in the range, an appropriate molecular weight and solution viscosity can be obtained.

As the polymerization method, all known methods and methods of combining the same can be used. The polymerization method in the production of polylysine is characterized by the order in which the monomers are added, and the various physical properties of the obtained polyimine can be controlled by controlling the order of addition of the monomers. Therefore, in the present invention, any monomer addition method can be used in the polymerization of polyproline. As a representative polymerization method, the following methods are mentioned. That is, it is the following method etc.

1) A method in which a diamine compound is dissolved in an organic polar solvent and reacted with substantially equimolar tetracarboxylic dianhydride to carry out polymerization.

2) A tetracarboxylic dianhydride is reacted with a diamine compound which is an excessively small amount of moietre in an organic polar solvent to obtain a prepolymer having an acid anhydride group at both terminals. Then, in all the steps, a method in which the dicarboxylic acid compound is polymerized by using a tetracarboxylic dianhydride and a diamine compound in substantially the same molar state is used.

3) A tetracarboxylic dianhydride is reacted with a diamine compound in an excess amount of mole relative to it in an organic polar solvent to obtain a prepolymer having an amine group at both terminals. Then, after the addition of the diamine compound, a method in which the tetracarboxylic dianhydride and the diamine compound are substantially monomolar is used to carry out polymerization using tetracarboxylic dianhydride in all the steps.

4) A method in which a tetracarboxylic dianhydride is dissolved and/or dispersed in an organic polar solvent, followed by polymerization using a diamine compound in a substantially molar manner.

5) A method in which a mixture of substantially equimolar tetracarboxylic dianhydride and a diamine compound is reacted in an organic polar solvent to carry out polymerization.

These methods may be used singly or in combination.

The conductive agent to be used in the production method of the present invention is not particularly limited, and any known one can be used as the conductive filler which can be contained in the filler-based conductive resin composition. For example, aluminum particles and SUS (Steel Use) can be used. Stainless, Japanese stainless steel standard) particles, carbon conductive particles, silver particles, gold particles, copper particles, titanium particles, alloy particles, and the like. Among these, carbon conductive particles can be preferably used because of the small specific gravity and the ease of weight reduction of the conductive film. Examples of the carbon conductive particles include Ketjen black, acetylene black, oil furnace black, and carbon nanotubes. The conductivity of the material itself is relatively high, and it is easy to It is particularly preferable to use a Ketchen black or a carbon nanotube for the reason that a small amount of the resin is added in a small amount to obtain a desired high conductivity.

The conductive agent is preferably contained in an amount of from 1 to 50 parts by weight, more preferably from 5 to 20 parts by weight, per 100 parts by weight of the polyamic acid. When the amount is less than 1 part by weight, the conductivity is lowered, and the function of the conductive film is impaired. On the other hand, if it is more than 50 parts by weight, the strength of the obtained conductive film is lowered, and the treatment becomes difficult. situation.

The preparation of the polyamine acid and the conductivity-imparting agent, that is, the preparation of the polyamic acid solution in which the conductivity-imparting agent is dispersed, for example, a method of adding a conductivity-imparting agent to the polymerization reaction liquid before or during the polymerization, 2. After the completion of the polymerization, a method of kneading the conductivity-imparting agent by using a three-roll mill or the like, 3. preparing a dispersion containing the conductivity-imparting agent, and mixing the same into the poly-proline solution

Etc. Any method can be used. From the viewpoint of suppressing contamination of the production line caused by the conductivity imparting agent to a minimum, it is preferred to mix the dispersion containing the conductivity imparting agent into the polyaminic acid solution, especially before the coating film is to be produced. The method. In the case of preparing a dispersion containing a conductivity imparting agent, it is preferred to use the same solvent as the polymerization solvent of polyamic acid. In order to satisfactorily disperse the conductive imparting agent or stabilize the dispersed state, a dispersing agent, a tackifier, or the like may be used within a range that does not affect the physical properties of the film. From the viewpoint of easily and stably dispersing the conductive imparting agent without agglomeration, it is preferred to add a small amount of a polyaminic acid solution as a precursor of the polyimine as a dispersing agent.

In the above composite, a ball mill, a bead mill, a sand mill, a colloid mill, a jet mill, a roll mill or the like is preferably used. When it is dispersed in a liquid form having fluidity by a method such as a bead mill or a ball mill, the handleability of the polyamic acid solution in which the conductivity imparting agent is dispersed in the film formation step is improved. The diameter of the medium used in the ball mill or the bead mill is not particularly limited, but is preferably 10 mm or less.

The filler may also be used for the purpose of improving the properties of the film such as the gliding property, the slidability, the thermal conductivity, the corona resistance, and the ring stiffness of the obtained conductive polyimide film. Any filler may be used, and preferred examples thereof include cerium oxide, titanium oxide, aluminum oxide, cerium nitride, boron nitride, calcium hydrogen phosphate, calcium phosphate, and mica.

Since the particle diameter of the filler is determined depending on the film properties to be modified and the type of the filler to be added, it is not particularly limited. Generally, the average particle diameter is preferably 0.05 to 100 μm, more preferably 0.1 to 75. The μm is further preferably 0.1 to 50 μm, and particularly preferably 0.1 to 25 μm. When the particle diameter is less than the above range, it is difficult to exhibit a reforming effect, and if it is larger than the above range, the surface property is largely impaired, or the film strength is largely lowered.

The number of additions of the filler is also determined depending on the film properties to be modified, the particle diameter of the filler, and the like, and is not particularly limited. In general, the amount of the filler added is preferably 0.01 to 100 parts by weight, more preferably 0.01 to 90 parts by weight, still more preferably 0.02 to 80 parts by weight, per 100 parts by weight of the polyimine. When the amount of the filler added is less than the above range, it may be difficult to exhibit a reforming effect by the filler, and if it is larger than the above range, the film strength may be largely impaired.

The method of adding the filler can be similarly applied to the above-described compounding and dispersing method, and may be added together with the polymerization agent to be combined or dispersed, or may be additionally added.

In the production method of the present invention, the polyamic acid is converted into a polyimine by a chemical hydrazine imidation method using a ruthenium iodide promoter, so that it can be dried in a short period of time and is excellent in productivity.

The hydrazine imidization accelerator may contain a catalyst and a chemical dehydrating agent, and may contain a solvent in addition to these. The solvent is preferably the same as those contained in the polyaminic acid solution.

A tertiary amine compound can be suitably used as the catalyst. As a preferable compound, quinoline, isoquinoline, 3,5-lutidine, 3,5-diethylpyridine, α-methylpyridine, β-methylpyridine, γ-methylpyridine can be mentioned. Wait. These compounds may be used singly or in combination of two or more.

The amount of the catalyst used is preferably from 0.1 to 4.0 mol equivalents, more preferably from 0.3 to 3.0 mol equivalents, and even more preferably from 0.5 to 2.0 mols, based on the proline acid 1 mol in the polyamic acid. equivalent. When it is less than 0.1 mol equivalent, there is a case where the effect of the catalyst is insufficient, and the ruthenium imidization is not completely performed, and the film strength is lowered. On the other hand, even if it is more than 4.0 molar equivalents, there is a case where the effect of increasing the amount of addition is hardly obtained, and it is difficult to evaporate the solvent in a series of heat treatments, and the amount of residuals is increased. The film strength obtained is still reduced.

The chemical dehydrating agent is not particularly limited, and for example, an aliphatic acid anhydride, an aromatic acid anhydride, a halogenated lower aliphatic acid anhydride, or the like can be suitably used. These may be used singly or in the form of a mixture of two or more. As a compound which is especially preferable in the above chemical dehydrating agent, acetic anhydride and propionic anhydride are mentioned. These compounds may be used singly or in combination of two or more kinds as described above.

The amount of the chemical dehydrating agent to be used is preferably 1.0 to 5.0 mol equivalents, more preferably 1.2 to 4.0 mol equivalents, and even more preferably 1.5 to 3.0, based on 1 mole of the valine acid in the polyamic acid. Moor equivalent. If it is less than 1.0 mol equivalent, there is a problem that the imidization of the hydrazine caused by the action of the chemical dehydrating agent is incomplete and the film strength is lowered. On the other hand, when it is more than 5.0 mol-equivalent, it may be imidated by a short time to cause gelation, and it may become difficult to form a coating film.

The temperature at which the ruthenium imidization accelerator is added to the polyglycolic acid is preferably 10 ° C or lower, more preferably 5 ° C or lower, and still more preferably 0 ° C or lower. When the temperature is higher than 10 ° C, the ruthenium imidization proceeds in a short time and gelation occurs, so that it is difficult to form a coating film.

In the production method of the present invention, a conductive polyimide film is formed by drying and yttrium-imiding a coating film containing the polyamic acid, a conductivity imparting agent, and a quinone imidization accelerator.

As a coating method for forming a coating film, for example, a die coating method, a spray method, a roll coating method, a spin coating method, a bar coating method, an inkjet method, a screen printing method, or a slit coating method can be suitably used. A well-known method such as law. By any of the above coating methods, it is equal to a metal drum or a metal belt The film is coated on the support, and a self-supporting dried film is obtained at a temperature of from room temperature to about 200 ° C, and then the film is fixed and heated to a temperature of about 600 ° C to obtain a conductive polyimide film. A known method such as a needle comb drawing method, a Brake web method, or a roll hanging method can be suitably employed for the fixing of the film, and the form is not limited thereto.

The heating temperature can be appropriately set, and since the oxime imidization is likely to occur at a high rate, the curing speed can be accelerated, which is preferable in terms of productivity. However, if the temperature is too high, there is a possibility of causing thermal decomposition. On the other hand, if the heating temperature is too low, the imidization is difficult to carry out, and the time required for the curing step is prolonged.

The heating time is not limited to a single time as long as it is sufficient for substantially terminating hydrazine imidation and drying, and is generally set to a range of about 1 to 600 seconds.

In the production method of the present invention, the thickness of the conductive polyimide film can be appropriately set by appropriately adjusting the thickness of the coating film on the support, the concentration of the polyaminic acid, and the weight fraction of the conductivity imparting agent. The thickness of the coating film is preferably from 1 to 1000 μm. If it is thinner than 1 μm, the film strength finally obtained may be insufficient, and if it is thicker than 1000 μm, it may flow on the support. The thickness of the finally obtained conductive polyimide film is preferably from 1 to 100 μm, more preferably from 5 to 50 μm. When it is thinner than 1 μm, the film strength may be insufficient. If it is thicker than 100 μm, it may become difficult to uniformly carry out the oxime imidization and drying, and thus the mechanical properties may be different or may become easy to occur. The case of a local defect such as a bubble.

In the production method of the present invention, since the volume resistivity and the surface resistivity of the obtained conductive polyimide film in the thickness direction can be adjusted as required, the type of the polyimide or the conductivity imparting agent can be appropriately set. Type, amount of addition, etc.

The volume resistivity of the conductive polyimide film in the thickness direction is preferably 1.0 × 10 ^-1 to 1.0 × 10 ² Ωcm, more preferably 1.0 × 10 ^-1 to 8.0 × 10 ¹ Ωcm, and still more preferably 1.0. ×10 ^-1 ~ 5.0 × 10 ¹ Ωcm.

The surface resistivity of the conductive polyimide film is preferably 1.0 × 10 ¹ to 1.0 × 10 ⁴ Ω / □, more preferably 1.0 × 10 ¹ to 5.0 × 10 ³ Ω / □, and still more preferably 1.0 × 10 ¹ ~ 3.0 × 10 ³ Ω / □.

The conductive polyimide film obtained by the method of the present invention preferably has a tear propagation resistance (R, unit) of the conductive polyimide film from the viewpoint that film transport can be stably performed during film formation. The range of :g/mm) is in the range of 130 to 300. If the value of R is within the preferred range, it can be judged that it has sufficient film strength. On the other hand, when the value of R is less than 130, the film strength is insufficient, so that not only the productivity is lowered but also the durability is lowered. In terms of productivity and durability, it is more preferable that the value of R is in the range of 160 to 300.

With respect to the conductive polyimide film obtained by the production method of the present invention, re-agglomeration of the conductivity-imparting agent is suppressed, and the desired volume resistivity and surface resistivity are obtained by using a minimum conductivity-imparting agent. Therefore, it can be suitably used for metal-based electronic materials, electrode materials for batteries, electromagnetic shielding materials, films for electrostatic adsorption, antistatic agents, image forming device parts, electronic devices, and the like, and can be suitably used for a long period of time.

[Examples]

The effects of the present invention will be more specifically described based on the examples and comparative examples, but the present invention is not limited thereto. Various changes, modifications, and changes may be made by the practitioner without departing from the scope of the invention.

The volume resistivity, surface resistivity, and film strength of the conductive polyimide film obtained in the examples and the comparative examples were evaluated and evaluated in the following manner.

(volume resistivity)

The obtained conductive polyimide film was cut into a size of 15 mm □, and a gold thin film was formed by sputtering in a region of 10 mm □ at the center of both sides. The copper foil was adhered to the gold film by a pressure of 1 MPa, and the potential V when the current I was passed between the two copper foils was measured, and the measured value V/I was taken as the volume resistivity. The resistance value was measured using LCR HiTESTER (3522-50, manufactured by Hioki Electric Co., Ltd.).

(surface resistivity)

The measurement was carried out by using a LORESTA-GP (MCP-T610, manufactured by Mitsubishi ANALYTECH Co., Ltd.), and a four-probe probe was pressed against the surface of the obtained conductive polyimide film to measure the surface resistivity.

If the volume resistivity is in the range of 1.0 × 10 ^-1 to 1.0 × 10 ² Ωcm and the surface resistivity is in the range of 1.0 × 10 ¹ to 1.0 × 10 ⁴ Ω / □, it is judged to be excellent in electric resistance. (○), if both the volume resistivity and the surface resistivity deviated from the range, it was evaluated that the electric resistance was poor (x).

(Evaluation of film strength)

The tear propagation resistance R of the obtained conductive polyimide film was measured in accordance with JIS K 7128 pants tear method. When the tear propagation resistance (R, unit: g/mm) value is in the range of 120 to 300, it is judged that the film strength is excellent (○), and if it is less than 120, the film strength is evaluated as poor (×).

(Example 1)

N,N-dimethylformamide (hereinafter referred to as DMF) is used as an organic solvent for polymerization, and pyromellitic dianhydride (hereinafter referred to as PMDA) 100 mol% is used as the tetracarboxylic dianhydride, and 1 is used. 1,3-bis(4-aminophenoxy)benzene (hereinafter referred to as TPE-R) having 3 aromatic rings in the molecule, 100 mol% as a diamine compound, substantially tetracarboxylic dianhydride and two The amine compound is added to the reaction tank in such a manner as to be equimolar %, and stirred to polymerize, thereby synthesizing the polyaminic acid solution. At this time, the solid content concentration of the obtained polyaminic acid solution was 15% by weight, and the viscosity was 300 to 400 Pa‧s (E-type viscometer manufactured by Toki Sangyo Co., Ltd., TVE-22H, at 23 The synthesis was carried out in the manner of °C.

10 parts by weight of the obtained polyaminic acid solution, 1 part by weight of Ketchen Black (ECP600JD, manufactured by LION Co., Ltd.), and 20 parts by weight of DMF were subjected to a dispersion treatment using a ball mill to obtain a carbon dispersion. Dispersion system using 5 mm The zirconia balls were set to have a treatment time of 30 minutes at a rotation number of 600 rpm.

Further, 100 parts by weight of the obtained carbon dispersion liquid and the obtained polylysine are dissolved 183 parts by weight of the liquid was mixed until homogeneous, and a carbon-dispersed polyaminic acid solution was obtained. At this time, the ketjen black was 10 parts by weight based on 100 parts by weight of the polyamic acid.

To the above carbon-dispersed polyaminic acid solution, 100 g of isoquinoline 11.4 g, acetic anhydride 12 g, and DMF 16.6 g of a hydrazine imidization promoter were added and uniformly formed on the aluminum foil to a final thickness of 25 The μm method was cast at a width of 40 cm and dried at 120 ° C for 216 seconds to obtain a self-supporting film. After the self-supporting film was peeled off from the aluminum foil, it was fixed by a needle, dried at 250 ° C for 200 seconds, and then dried at 400 ° C for 64 seconds to obtain a conductive polyimide film. The volume resistivity, surface resistivity, and film strength of the obtained conductive polyimide film were measured.

(Example 2)

DMF was used as an organic solvent for polymerization, and PMDA 100 mol% was used as the tetracarboxylic dianhydride, and 2,2'-bis{4-(4-aminophenoxy) having 4 aromatic rings in one molecule was used. Phenyl}propane (hereinafter referred to as BAPP) 100 mol% as a diamine compound, which is added to the reaction tank in such a manner that substantially the tetracarboxylic dianhydride and the diamine compound become equimolar %, and is stirred. Polymerization, thereby synthesizing a polyaminic acid solution. At this time, the solid content concentration of the obtained polyaminic acid solution was 15% by weight, and the viscosity was 300 to 400 Pa‧s (E-type viscometer manufactured by Toki Sangyo Co., Ltd., TVE-22H, 23 ° C Synthesize in the same way.

10 parts by weight of the obtained polyaminic acid solution, 1 part by weight of Ketchen Black (ECP600JD, manufactured by LION Co., Ltd.), and 20 parts by weight of DMF were subjected to a dispersion treatment using a ball mill to obtain a carbon dispersion. Dispersion system using 5 mm The zirconia balls were set to have a treatment time of 30 minutes at a rotation number of 600 rpm.

Further, 100 parts by weight of the obtained carbon dispersion and 183 parts by weight of the obtained polyamidonic acid solution were mixed to be uniform to obtain a carbon-dispersed polyamine solution. At this time, the ketjen black was 10 parts by weight based on 100 parts by weight of the polyamic acid.

Adding 9.3 g of isoquinoline to 100 g of the above carbon-dispersed polyamido acid solution, Acetic anhydride 9.7 g, and DMF 21 g of hydrazine imidization promoter and homogenized on aluminum foil to a thickness of 40 μm in a final thickness of 40 μm, and at 120 ° C for 216 seconds Dry to obtain a self-supporting film. After the self-supporting film was peeled off from the aluminum foil, it was fixed by a needle, dried at 250 ° C for 200 seconds, and then dried at 400 ° C for 64 seconds to obtain a conductive polyimide film. The volume resistivity, surface resistivity, and film strength of the obtained conductive polyimide film were measured.

(Example 3)

A conductive polyimide film was obtained in the same manner as in Example 2 except that the final thickness was 12.5 μm. The volume resistivity, surface resistivity, and film strength of the obtained conductive polyimide film were measured.

(Example 4)

DMF is used as an organic solvent for polymerization, and PMDA 100 mol% is used as the tetracarboxylic dianhydride, and 1,3-bis{4-(3-aminophenoxy)benzene having 5 aromatic rings in one molecule is used. Methyl benzene (hereinafter referred to as BABB) 100 mol% as a diamine compound, which is added to the reaction tank in such a manner that substantially the tetracarboxylic dianhydride and the diamine compound become equimolar %, and is stirred. The polymerization is carried out to synthesize a polyaminic acid solution. At this time, the solid content concentration of the obtained polyaminic acid solution was 15% by weight, and the viscosity was 300 to 400 Pa‧s (E-type viscometer manufactured by Toki Sangyo Co., Ltd., TVE-22H, 23 ° C Synthesize in the same way.

10 parts by weight of the obtained polyaminic acid solution, 1 part by weight of Ketchen Black (ECP600JD, manufactured by LION Co., Ltd.), and 20 parts by weight of DMF were subjected to a dispersion treatment using a ball mill to obtain a carbon dispersion. Dispersion system using 5 mm The zirconia balls were set to have a treatment time of 30 minutes at a rotation number of 600 rpm.

Further, 100 parts by weight of the obtained carbon dispersion and 183 parts by weight of the obtained polyamidonic acid solution were mixed to be uniform to obtain a carbon-dispersed polyamine solution. At this time, the ketjen black was 10 parts by weight based on 100 parts by weight of the polyamic acid.

To the above-mentioned carbon-dispersed polyaminic acid solution, 100 g of an quinone imidization accelerator containing 8.1 g of isoquinoline, 8.5 g of acetic anhydride, and 23.4 g of DMF was added and homogenized on the aluminum foil to a final thickness of 25 The μm method was cast at a width of 40 cm and dried at 120 ° C for 216 seconds to obtain a self-supporting film. After the self-supporting film was peeled off from the aluminum foil, it was fixed by a needle, dried at 250 ° C for 200 seconds, and then dried at 400 ° C for 64 seconds to obtain a conductive polyimide film. The volume resistivity, surface resistivity, and film strength of the obtained conductive polyimide film were measured.

(Example 5)

Using DMF as an organic solvent for polymerization, using PMDA 50 mol%, 3,3',4,4'-benzophenonetetracarboxylic dianhydride 50 mol% as tetracarboxylic dianhydride, using 1 molecule 4,4'-diaminodiphenyl ether having 2 aromatic rings (hereinafter referred to as ODA) 50 mol%, BAPP 50 mol% having 4 aromatic rings in one molecule as a diamine compound, substantially The tetracarboxylic dianhydride and the diamine compound are added to the reaction tank in such a manner as to be equimolar %, and stirred to be polymerized, thereby synthesizing the polyaminic acid solution. At this time, the solid content concentration of the obtained polyaminic acid solution was 15% by weight, and the viscosity was 300 to 400 Pa‧s (E-type viscometer manufactured by Toki Sangyo Co., Ltd., TVE-22H, 23 ° C Synthesize in the same way.

10 parts by weight of the obtained polyaminic acid solution, 1 part by weight of Ketchen Black (ECP600JD, manufactured by LION Co., Ltd.), and 20 parts by weight of DMF were subjected to a dispersion treatment using a ball mill to obtain a carbon dispersion. Dispersion system using 5 mm The zirconia balls were set to have a treatment time of 30 minutes at a rotation number of 600 rpm.

Further, 100 parts by weight of the obtained carbon dispersion and 183 parts by weight of the obtained polyamidonic acid solution were mixed to be uniform to obtain a carbon-dispersed polyamine solution. At this time, the ketjen black was 10 parts by weight based on 100 parts by weight of the polyamic acid.

To the above-mentioned carbon-dispersed polyaminic acid solution, 100 g of an isoquinoline 10.1 g, acetic anhydride 10.6 g, and DMF 19.3 g of a hydrazine imidization promoter were added and made uniform in aluminum foil. A self-supporting film was obtained by casting at a final thickness of 25 μm in a width of 40 cm and drying at 120 ° C for 216 seconds. After the self-supporting film was peeled off from the aluminum foil, it was fixed by a needle, dried at 250 ° C for 200 seconds, and then dried at 400 ° C for 64 seconds to obtain a conductive polyimide film. The volume resistivity, surface resistivity, and film strength of the obtained conductive polyimide film were measured.

(Example 6)

A conductive polyimide film was obtained in the same manner as in Example 2 except that 3,5-diethylpyridine was used instead of the isoquinoline. The volume resistivity, surface resistivity, and film strength of the obtained conductive polyimide film were measured.

(Comparative Example 1)

DMF is used as an organic solvent for polymerization, and PMDA 100 mol% is used as the tetracarboxylic dianhydride, and 100 mol% of p-phenylenediamine (hereinafter referred to as p-PDA) having one aromatic ring in one molecule is used as two. The amine compound is added to the reaction tank in such a manner that substantially the tetracarboxylic dianhydride and the diamine compound become equimolar %, and the mixture is stirred to polymerize, thereby synthesizing the polyaminic acid solution. At this time, the solid content concentration of the obtained polyaminic acid solution was 15% by weight, and the viscosity was 300 to 400 Pa‧s (E-type viscometer manufactured by Toki Sangyo Co., Ltd., TVE-22H, 23 ° C Synthesize in the same way.

10 parts by weight of the obtained polyaminic acid solution, 1 part by weight of Ketchen Black (ECP600JD, manufactured by LION Co., Ltd.), and 20 parts by weight of DMF were subjected to a dispersion treatment using a ball mill to obtain a carbon dispersion. Dispersion system using 5 mm The zirconia balls were set to have a treatment time of 30 minutes at a rotation number of 600 rpm.

Further, 100 parts by weight of the obtained carbon dispersion and 183 parts by weight of the obtained polyamidonic acid solution were mixed to be uniform to obtain a carbon-dispersed polyamine solution. At this time, the ketjen black was 10 parts by weight based on 100 parts by weight of the polyamic acid.

To the above-mentioned carbon-dispersed polyaminic acid solution, 100 g of an isoquinoline containing 17.8 g, acetic anhydride 18.8 g, and DMF 3.4 g of a hydrazine imidization accelerator was added and uniformly homogenized on the aluminum foil. A self-supporting film was obtained by casting at a final thickness of 25 μm in a width of 40 cm and drying at 120 ° C for 216 seconds. After the self-supporting film was peeled off from the aluminum foil, it was fixed by a needle, dried at 250 ° C for 200 seconds, and then dried at 400 ° C for 64 seconds to obtain a conductive polyimide film. The volume resistivity, surface resistivity, and film strength of the obtained conductive polyimide film were measured.

(Comparative Example 2)

DMF is used as an organic solvent for polymerization, PMDA 100 mol% is used as the tetracarboxylic dianhydride, and ODA 100 mol% having two aromatic rings in one molecule is used as the diamine compound to substantially tetracarboxylic dianhydride. The polyamine acid solution is synthesized by adding it to the reaction tank in such a manner that the diamine compound becomes equimolar % and stirring it. At this time, the solid content concentration of the obtained polyaminic acid solution was 15% by weight, and the viscosity was 300 to 400 Pa‧s (E-type viscometer manufactured by Toki Sangyo Co., Ltd., TVE-22H, 23 ° C Synthesize in the same way.

10 parts by weight of the obtained polyaminic acid solution, 1 part by weight of Ketchen Black (ECP600JD, manufactured by LION Co., Ltd.), and 20 parts by weight of DMF were subjected to a dispersion treatment using a ball mill to obtain a carbon dispersion. Dispersion system using 5 mm The zirconia balls were set to have a treatment time of 30 minutes at a rotation number of 600 rpm.

Further, 100 parts by weight of the obtained carbon dispersion and 183 parts by weight of the obtained polyamidonic acid solution were mixed to be uniform to obtain a carbon-dispersed polyamine solution. At this time, the ketjen black was 10 parts by weight based on 100 parts by weight of the polyamic acid.

To the above-mentioned carbon-dispersed polyaminic acid solution, 100 g of an isoquinoline 13.9 g, acetic anhydride 14.6 g, and DMF 11.5 g of a hydrazine imidization accelerator were added and uniformly formed on an aluminum foil to have a final thickness of 25 The μm method was cast at a width of 40 cm and dried at 120 ° C for 216 seconds to obtain a self-supporting film. After the self-supporting film was peeled off from the aluminum foil, it was fixed by a needle, dried at 250 ° C for 200 seconds, and then dried at 400 ° C for 64 seconds to obtain a conductive polyimide film. Conducting the obtained conductive poly Determination of volume resistivity, surface resistivity, and film strength of the quinone imine film.

(Comparative Example 3)

100 g of the carbon-dispersed polyaminic acid solution obtained in Example 2 was cast on a PET film in a width of 40 μm so as to have a final thickness of 25 μm, and dried at 70 ° C for 600 seconds. After the dried self-supporting film is peeled off from the PET film, it is fixed to a needle card tenter and dried while heating from 160 ° C to 300 ° C for 450 seconds, followed by drying at 400 ° C for 180 seconds. A conductive polyimide film was obtained. The volume resistivity, surface resistivity, and film strength of the obtained conductive polyimide film were measured.

(Comparative Example 4)

100 g of the carbon-dispersed polyaminic acid solution obtained in Comparative Example 2 was cast on a PET film so as to have a final thickness of 25 μm in a width of 40 cm, and dried at 70 ° C for 600 seconds. After the dried self-supporting film is peeled off from the PET film, it is fixed to a needle card tenter and dried while heating from 160 ° C to 300 ° C for 450 seconds, followed by drying at 400 ° C for 180 seconds. A conductive polyimide film was obtained. The volume resistivity, surface resistivity, and film strength of the obtained conductive polyimide film were measured.

The evaluation results of the films of the above examples and comparative examples are shown in Table 1.

As shown in Table 1, the electrical resistance of the conductive polyimide film obtained in Examples 1 to 6, The film strength was good. On the other hand, the conductive polyimide film obtained in Comparative Examples 1 and 2 failed to have both electric resistance and film strength.

Further, in Example 2 and Comparative Example 3, the same polyimine structure was produced by a chemical hydrazine imidation method or a thermal hydrazylation method, and the same resistance was obtained regardless of the preparation method. Conductive polyimide film with film strength. On the other hand, in Comparative Example 2 and Comparative Example 4, the same polyimine structure was produced by a chemical hydrazine imidation method or a thermal hydrazylation method, respectively, by a chemical hydrazylation method. The gain of the obtainer was high, and the conductive polyimide film which is equivalent to the thermal imidization method was not obtained.

Thereby, it is clear that the manufacturing method of the present invention is effective.

Claims (13)

A method for producing a conductive polyimide film, which comprises a method for producing a conductive polyimide film containing a conductive agent and a polyimide resin, and containing (A) a pyrene-containing film a tetracarboxylic dianhydride component of tetracarboxylic dianhydride, a polyamine acid obtained by reacting a diamine compound component containing a diamine having three or more aromatic rings in one molecule, (B) a conductivity imparting agent, and C) Drying of the coating film and hydrazine imidization of the hydrazine imidization accelerator. The method for producing a conductive polyimide film according to claim 1, wherein the diamine having three or more aromatic rings in the one molecule has any one of the following general formulae (1) to (6) in the molecule; Representing the structure, (The aromatic ring in the general formulae (1) to (6) may be partially substituted by a halogen, an alkyl group, an alkyl halide, an alkoxy group, a phenyl group or a phenoxy group). The method for producing a conductive polyimide film according to claim 1 or 2, wherein the diamine having three or more aromatic rings in the above molecule is a compound represented by the following formula (7). (In the formula (7), Ar represents an aromatic ring; and X is any one selected from the group consisting of O, a direct bond, CO, C(CH ₃ ) ₂ , S, and SO ₂ , and may be in one molecule. All of the same, may be partially or completely different; n≧2; and, with respect to Ar, a part thereof may also be substituted by halogen, alkyl, halogenated alkyl, alkoxy, phenyl, or phenoxy group in one molecule. They may all be the same, or they may be partially or completely different). The method for producing a conductive polyimide film according to any one of claims 1 to 3, wherein the diamine having three or more aromatic rings in the one molecule is selected from the following chemical formulas (8) to (16) At least one of the groups consisting of the compounds, The method for producing a conductive polyimide film according to any one of claims 1 to 4, wherein the content of the pyromellitic dianhydride is 50 to 100% in 100 mol% of the tetracarboxylic dianhydride component. The content of the ear %, and/or the diamine having three or more aromatic rings in the above molecule is 50 to 100 mol% in 100 mol% of the diamine compound component. The method for producing a conductive polyimide film according to any one of claims 1 to 5, wherein the (B) conductivity imparting agent contains carbon conductive particles. The method for producing a conductive polyimide film according to any one of claims 1 to 6, wherein the content of the (B) conductivity imparting agent is 1 to 50 by weight based on 100 parts by weight of the (A) polyphthalic acid. Share. The method for producing a conductive polyimide film according to any one of claims 1 to 7, wherein the (C) quinone imidization accelerator comprises a catalyst and a chemical dehydrating agent. The method for producing a conductive polyimide film according to claim 8, wherein the (C) quinone imine The amount of the catalyst used in the accelerator is in the range of 0.1 to 4.0 mol equivalents based on 1 mole of the valine acid in the above (A) polyphthalic acid. The method for producing a conductive polyimide film according to claim 8 or 9, wherein the amount of the chemical dehydrating agent of the above (C) quinone imidization accelerator is relative to that of the above (A) polyamine The acid 1 molar is in the range of 1.0 to 5.0 mole equivalents. The method for producing a conductive polyimide film according to any one of claims 1 to 10, wherein the conductive polyimide film has a thickness of from 1 to 100 μm. The method for producing a conductive polyimide film according to any one of claims 1 to 11, wherein the volume resistivity of the conductive polyimide film in the thickness direction is 1.0 × 10 ^-1 to 1.0 × 10 ² Ωcm Within the range, and/or the surface resistivity is in the range of 1.0 × 10 ¹ to 1.0 × 10 ⁴ Ω / □. The method for producing a conductive polyimide film according to any one of claims 1 to 12, wherein the conductive polyimide film has a tear propagation resistance (R, unit: g/mm) of 120 to 300. Within the scope.