WO2020091146A1 - Polyimide precursor composition for improving adhesion of polyimide film and polyimide film prepared therefrom - Google Patents

Abstract

The present invention provides a polyimide precursor composition comprising: a polyamic acid solution prepared by polymerizing one or more kinds of dianhydride monomer and at least one kind of diamine monomer in an organic solvent; an aromatic carboxylic acid having four or more carboxyl groups; and an antioxidant, wherein the dianhydride monomer includes an adhesive dianhydride monomer represented by chemical formula 1, and a polyimide film prepared therefrom has an elongation of 13% or more.

Description

Polyimide precursor composition for improving adhesion of polyimide film and polyimide film prepared therefrom

The present invention relates to a polyimide precursor composition for improving the adhesion of a polyimide film, and a polyimide film prepared therefrom.

Polyimide (PI) is a polymer material with thermal stability based on a rigid aromatic backbone and has mechanical properties such as excellent strength, chemical resistance, weather resistance, and heat resistance based on the chemical stability of the imide ring.

In addition, polyimide is in the spotlight as a high-performance polymer material that can be applied to a wide range of industries such as electronics, communications, and optics due to its excellent electrical properties such as insulation properties and low dielectric constant.

Recently, as various electronic devices have become thinner, lighter, and smaller, many studies have been conducted to use a light and flexible thin polyimide film as a display substrate that can replace an insulating material of a circuit board or a glass substrate for a display. .

In particular, in the case of a polyimide film used in a circuit board or display substrate manufactured at a high process temperature, it is necessary to secure a higher level of dimensional stability, heat resistance and mechanical properties.

As one of the methods for securing such properties, a method of increasing the molecular weight of the polyimide is exemplified.

This is because the more imide groups in the molecule can improve the heat resistance and mechanical properties of the polyimide film, and the longer the polymer chain is, the higher the proportion of imide groups is.

In order to prepare a high molecular weight polyimide, it is common to prepare a polyamic acid as a precursor at a high molecular weight and imidize it through heat treatment.

However, the higher the molecular weight of the polyamic acid, the higher the viscosity of the polyamic acid solution in a state in which the polyamic acid is dissolved in a solvent, resulting in a problem that the fluidity decreases and the process handling becomes very low.

In addition, in order to lower the viscosity of the polyamic acid while maintaining the molecular weight of the polyamic acid, a method of lowering the content of the solid content and increasing the solvent content may be considered, but in this case, as a large amount of solvent must be removed during the curing process, manufacturing cost and process time This increasing problem can occur.

On the other hand, in general, polyimide resins undergo chemical changes, ie oxidation reactions, in the presence of oxygen by light, heat, pressure, shear force, and the like. This oxidation reaction causes a problem of deteriorating the heat resistance and mechanical properties of the polyimide film produced by generating a change in physical properties by cutting, crosslinking, etc. of the molecular chain in the polyimide resin.

In order to solve this problem, a method of adding a small amount of an additive such as an antioxidant is used, and the antioxidant removes oxygen atoms of an already oxidized polyimide resin, thereby stabilizing the polyimide resin. As a thing, a phosphate compound and a sulfur compound are typically used.

However, generally used antioxidants have properties that decompose at high temperatures, and in particular, in the production of polyimide resins, it is common that high temperature heat treatment for imidization is involved, so that the antioxidants are decomposed to reduce the antioxidant effect. In some cases, there is a problem that these effects are not exerted at all.

On the other hand, in general, a polyimide film is prepared through a method of forming a gel film by forming a polyamic acid on a support and drying the gel film, and imidizing the gel film. There is a problem that a lifting phenomenon in which a part of the phase is peeled off occurs.

That is, since the polyamic acid composed of the dianhydride monomer and the diamine monomer is a material having very low or little adhesion to a support made of an inorganic substrate, a problem of separation from the support may occur during the manufacturing process.

As such, there are many difficulties in improving the properties required for the polyimide film, and in particular, manufacturing a polyimide film that satisfies several properties at the same time is an ongoing research subject in the related art.

Therefore, there is a high need to develop a technology that satisfies all the characteristics required for the polyimide film described above.

The object of the present invention, even if the solid content of the polyamic acid solution is high, the viscosity is kept low, satisfies the heat resistance and mechanical properties of the polyimide film produced therefrom at the same time, the adhesion to the support in the manufacturing process of the polyimide film It is to provide an excellent imide precursor composition and a polyimide film prepared therefrom.

According to an aspect of the present invention, a polyamic acid solution prepared by polymerizing one or more dianhydride monomers and one or more diamine monomers in an organic solvent. A polyimide precursor composition comprising an aromatic carboxylic acid having 4 or more carboxyl groups and an antioxidant is disclosed as an essential factor for the implementation of a polyimide film satisfying the above properties. In particular, the dianhydride monomer may satisfy the above-described properties by including an adhesive dianhydride monomer.

Accordingly, the present invention has a practical purpose to provide a specific embodiment thereof.

The present invention is a polyamic acid solution prepared by polymerizing one or more dianhydride monomers and one or more diamine monomers in an organic solvent;

Aromatic carboxylic acids having 4 or more carboxyl groups; And

Contains antioxidants,

The dianhydride monomer includes an adhesive dianhydride monomer represented by the following Chemical Formula 1,

A polyimide precursor composition having an elongation of 13% or more of a polyimide film prepared therefrom is provided.

(One)

In Chemical Formula 1, X ₁ and X ₂ may be each independently selected from the group consisting of C1-C3 alkyl group, aryl group, carboxyl group, hydroxy group, fluoroalkyl group, and sulfonic acid group,

When X ₁ and X ₂ are plural, they may be the same or different from each other,

n1 and n2 are each independently an integer of 0 to 3.

When the polyimide precursor composition is used, process handling may be improved due to a relatively low viscosity while having a high solid content, and the polyimide film produced therefrom has excellent heat resistance and mechanical properties, and a polyimide film It was found that the cutability and yield of the product were improved.

Therefore, specific details for its implementation will be described herein.

Prior to this, the terms or words used in the present specification and claims should not be construed as being limited to ordinary or lexical meanings, and the inventor appropriately explains the concept of terms to explain his or her invention in the best way. Based on the principle that it can be defined, it should be interpreted as meanings and concepts consistent with the technical spirit of the present invention.

Therefore, the configuration of the embodiments described herein is only one of the most preferred embodiments of the present invention and does not represent all of the technical spirit of the present invention, and various equivalents and modifications that can replace them at the time of this application It should be understood that examples may exist.

In the present specification, a singular expression includes a plural expression unless the context clearly indicates otherwise. In this specification, the terms "include", "have" or "have" are intended to indicate the presence of implemented features, numbers, steps, elements or combinations thereof, one or more other features or It should be understood that the existence or addition possibilities of numbers, steps, elements, or combinations thereof are not excluded in advance.

As used herein, "dianhydride (dianhydride)" is intended to include its precursors or derivatives, which may not technically be dianhydrides, but nevertheless react with diamines to form polyamic acids. And this polyamic acid can be converted back to polyimide.

“Diamine” as used herein is intended to include precursors or derivatives thereof, which may not technically be diamines, but will nevertheless react with dianhydrides to form polyamic acids, which polyamic acids are again polydi Can be converted to mead.

Where an amount, concentration, or other value or parameter herein is given as an enumeration of ranges, preferred ranges, or preferred upper and lower limits, any upper limit of any pair of any pair, regardless of whether the ranges are disclosed separately or It should be understood to specifically disclose all ranges formed of preferred values and any lower range limits or preferred values.

When a range of numerical values is referred to herein, unless stated otherwise, that range is intended to include the endpoints and all integers and fractions within the range.

It is intended that the scope of the invention not be limited to the specific values recited when defining a range.

First aspect: polyimide precursor composition

The polyimide precursor composition according to the present invention includes: a polyamic acid solution prepared by polymerizing one or more dianhydride monomers and one or more diamine monomers in an organic solvent;

Aromatic carboxylic acids having 4 or more carboxyl groups; And

Contains antioxidants,

The dianhydride monomer includes an adhesive dianhydride monomer represented by the following Chemical Formula 1,

Characterized in that the elongation of the polyimide film prepared therefrom is 13% or more.

(One)

In Chemical Formula 1, X ₁ and X ₂ may be each independently selected from the group consisting of C1-C3 alkyl group, aryl group, carboxyl group, hydroxy group, fluoroalkyl group, and sulfonic acid group,

When X ₁ and X ₂ are plural, they may be the same or different from each other,

n1 and n2 are each independently an integer of 0 to 3.

In Formula 1, when the substituent of the benzene ring is not specifically designated, it means hydrogen.

The adhesive dianhydride monomer represented by Chemical Formula 1 includes a carbonyl group (C = O), which is a polar functional group, between two benzene rings, and this polar functional group adheres between a polyimide film and a surface of a support composed of an inorganic substrate. Improves the reaction.

The adhesion reaction includes, for example, physical bonding between the polyimide film and the surface of the support, hydrogen bonding between the polyimide film and the metalloid oxide or metal oxide film on the surface of the support, and chemical adsorption between the polyimide film and the surface of the support. Can be.

Specifically, in the present invention, the carbonyl group included in the adhesive dianhydride monomer improves the chemical adsorption reaction by the polar functional group during the adhesion reaction as described above, and the gel film is dried or supported in the process of manufacturing the polyimide film. It is possible to minimize the lifting phenomenon in which a part of the phase is peeled off.

The adhesive dianhydride monomer that can be particularly preferably used in the present invention is 2,3,3 ', 4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-benzophenone It may include one or more selected from the group consisting of tetracarboxylic dianhydride (BTDA), but is not limited thereto.

Next, the aromatic carboxylic acid is 3,3 ', 4,4'-biphenyltetracarboxylic acid (3,3', 4,4'-biphenyltetracarboxylic acid, BPTA), pyromellitic acid (PMA) , 1,2,3,4-benzenetetracarboxylic acid, benzophenone-3,3 ', 4,4'-tetracarboxylic acid (benzophenone-3,3', 4,4'-tetracarboxylic acid, pyrazine tetracarboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid (2,3,6,7-naphthalenetetracarboxylic acid) and naphthalene-1,4,5 , 8-tetracarboxylic acid (naphthalene-1,4,5,8-tetracarboxylic acid) may include one or more selected from the group consisting of.

In the present invention, aromatic carboxylic acids having 4 or more carboxyl groups are not polymerized with polyamic acid at a temperature in the process of polymerizing a polyamic acid solution or preparing a polyimide precursor composition, for example, at a temperature of 40 to 90 ° C. Subsequently, upon heat treatment for imidization, a closed ring dehydration reaction is caused, so that a carboxyl group may form a dianhydride group.

When the aromatic carboxyl group forms a dianhydride group, the terminal amine group of the polyamic acid chain or the polyimide chain can react with the dianhydride group to increase the length of the polymer chain while forming an amic acid group.

The amic acid group thus generated may be imidized at a high temperature to increase the length of the polyimide chain.

As described above, the polyimide precursor composition containing the aromatic carboxylic acid can maintain a low viscosity, thereby significantly improving process handling. In addition, by increasing the length of the polymer chain during heat treatment for imidization, mechanical properties and heat resistance can be remarkably improved compared to polyimide prepared using polyamic acid having a similar molecular weight.

Based on the 100 mol% of the diamine monomer, the content of the dianhydride monomer is 93 to 98.8 mol%, the content of the adhesive dianhydride monomer is 1 to 5 mol%, and having four or more carboxyl groups The content of aromatic carboxylic acid may be 0.2 to 2 mol%.

First, when the content of the adhesive dianhydride monomer exceeds the above range, heat resistance and mechanical properties of the polyimide film may be deteriorated.

In addition, an increase in the carbonyl group included in the monomer may increase the hygroscopicity of the polyimide film, and thus a problem such as an increase in the dielectric constant of the polyimide film may occur.

Conversely, when the content of the adhesive dianhydride monomer is less than the above range, it is not preferable because the desired degree of adhesion cannot be secured.

Next, when the content of the aromatic carboxylic acid exceeds the above range, the heat resistance of the polyimide film may be lowered, flexibility may be lowered, and defects may occur in the appearance of the film. It is not preferable because a desired low viscosity cannot be achieved.

Meanwhile, the antioxidant may have a 5% by weight decomposition temperature of 380 ° C or higher, and specifically, 5% by weight decomposition temperature of 400 ° C or higher.

Specifically, the antioxidant may include a compound represented by Formula 2 below.

(2)

In Chemical Formula 2, R ₁ to R ₆ may each independently be selected from the group consisting of C1-C3 alkyl groups, aryl groups, carboxylic acid groups, hydroxy groups, fluoroalkyl groups, and sulfonic acid groups,

n is an integer from 1 to 4,

When R ₁ to R ₆ are plural, they may be the same or different from each other,

m1 to m6 are each independently an integer of 0 to 3.

In Formula 2, when the substituent of the benzene ring is not specifically designated, it means hydrogen.

In one specific example, n in Formula 2 may be 1, m1 to m6 may be 0, and more specifically, the antioxidant may include a compound of Formula 2-1.

(2-1)

Since these antioxidants have low volatility and excellent thermal stability, they do not decompose or volatilize during the production process of the polyimide film, and thus exhibit an effect of preventing oxidation of the amide group or the imide group of the polyimide film in the polyimide precursor composition. Can be.

Conversely, in the case of an antioxidant having a 5 wt% decomposition temperature of 380 ° C or less, the polyimide film is decomposed by high temperature during the manufacturing process, and thus cannot exhibit the effect of introducing the above antioxidant.

The antioxidant may be included in the range of 0.1 to 2 parts by weight based on 100 parts by weight of the solid content of the polyimide precursor composition.

When the content of the antioxidant exceeds the above range, the heat resistance of the polyimide film may deteriorate, and deposition or blooming may occur in the polyimide film, thereby deteriorating mechanical properties, and film appearance. It is not desirable because it may cause defects.

Conversely, when the content of the antioxidant is less than the above range, it is not preferable because the antioxidant effect cannot be sufficiently exhibited.

The polyimide precursor composition may include 10 to 20% by weight of solids based on the total weight of the polyimide precursor composition.

When the solid content of the polyimide precursor composition exceeds the above range, it is not preferable because the viscosity of the polyimide precursor composition is inevitably increased, and conversely, when the solid content of the polyimide precursor composition falls below the above range. In, as a large amount of solvent has to be removed during the curing process, a problem that manufacturing cost and process time increase may occur.

In addition, the polyimide precursor composition may have a viscosity at 23 ° C of 1,000 to 20,000 cp, specifically 2,000 to 10,000 cP, and more specifically 3,000 to 6,000 cP.

The polyimide precursor composition having such a viscosity has an advantage of easy handling in the process in terms of fluidity, and may be advantageous in film forming. Specifically, when the viscosity of the polyimide precursor composition exceeds the above range, higher pressure must be applied by friction with the pipe when the polyimide precursor composition is moved through the pipe during the polyimide production process. Process costs are increased and handling is degraded. In addition, the higher the viscosity, the more time and cost may be required for the mixing process.

On the other hand, when the viscosity of the polyimide precursor composition is less than the above range, a problem that an increase in manufacturing cost and process time may occur as a large amount of solvent must be removed during curing.

Meanwhile, the polyimide precursor composition may further include a silicone-based additive.

The polyimide precursor composition may contain 0.01 to 0.05 parts by weight of a silicone-based additive with respect to 100 parts by weight of solid content.

When the content of the silicone-based additive exceeds the above range, the mechanical properties of the polyimide film to be produced may be deteriorated, and the silicone-based additive is decomposed at a high temperature during heat treatment for imidization, thereby increasing the adhesion between the gel film and the support. It is not preferable because it may decrease.

On the other hand, when the content of the silicone-based additive is less than the above range, it is not preferable because it cannot exert a sufficient effect to improve the smoothness of the surface of the polyimide film to be produced.

The silicone-based additive is, for example, dimethylpolysiloxane (dimethylpolysiloxane),

Polyether-modified polydimethylsiloxane (Polyether modified polydimethysiloxane) polymethylalkylsiloxane (Polymethylalkylsiloxane, hydroxyl group (-OH) and may include one or more selected from the group consisting of silicone additives including a double bond structure (C = C). However, it is not limited to this alone.

In one specific example, the polyimide precursor composition may further include an alkoxy silane coupling agent.

Specifically, it may include 0.01 to 0.05 parts by weight of an alkoxy silane coupling agent with respect to 100 parts by weight of the solid content of the polyimide precursor composition.

When the content of the alkoxy silane coupling agent exceeds the above range, mechanical properties may be deteriorated, and upon heat treatment for imidization, the alkoxy silane coupling agent decomposes at a high temperature to decrease the adhesion between the gel film and the support rather. This is not desirable.

On the other hand, when the content of the alkoxy silane coupling agent is less than the above range, it is not preferable because the effect of suppressing peeling on the support cannot be sufficiently exhibited.

The alkoxy silane coupling agent is, for example, 3-aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, 3-aminopropyl methyl dimethoxysilane, 3-aminopropyl methyl diethoxysilane, 3- (2 -Aminoethyl) aminopropyl trimethoxysilane, 3-phenylaminopropyl trimethoxysilane, 2-aminophenyl trimethoxysilane, and 3-aminophenyl trimethoxysilane. It can, but is not limited to this.

Meanwhile, as described above, the polyamic acid solution may be produced by polymerization of one or more dianhydride monomers and one or more diamine monomers.

The dianhydride monomer that can be used in the production of the polyamic acid of the present invention may be an aromatic tetracarboxylic dianhydride.

The aromatic tetracarboxylic dianhydride is pyromellitic dianhydride (or PMDA), 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride (or BPDA), 2,3,3 ', 4'-biphenyltetracarboxylic dianhydride (or a-BPDA), oxydiphthalic dianhydride (or ODPA), diphenylsulfone-3,4,3', 4'-tetracarboxylic Dianhydride (or DSDA), bis (3,4-dicarboxyphenyl) sulfide dianhydride, 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3- Hexafluoropropane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, p-phenylenebis (Trimellitic monoester acid anhydride), p-biphenylenebis (Trimellitic monoester acid anhydride), m-terphenyl-3,4,3 ', 4'-tetracarboxylic Anhydride, 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-di Carboxyphenoxy) phenyl] propane dianhydride (BPADA), 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 4,4 And '-(2,2-hexafluoroisopropylidene) diphthalic acid dianhydride. These can be used alone or in combination of two or more as desired.

These may be used alone or in combination of two or more as desired, but the dianhydride monomers that can be particularly preferably used in the present invention are pyromellitic dianhydrides (PMDA), 3,3 ', 4,4. One or more selected from the group consisting of '-biphenyltetracarboxylic dianhydride (s-BPDA) and 2,3,3', 4'-biphenyltetracarboxylic dianhydride (a-BPDA) Can be.

The diamine monomers that can be used in the production of the polyamic acid solution of the present invention are aromatic diamines, and are classified as follows.

1) 1,4-diaminobenzene (or paraphenylenediamine, PDA), 1,3-diaminobenzene, 2,4-diaminotoluene, 2,6-diaminotoluene, 3,5-diaminobenzo Diamines having one benzene nucleus in the structure, such as diacid (or DABA), etc., which have a relatively rigid structure in diamine;

2) Diaminodiphenyl ethers such as 4,4'-diaminodiphenyl ether (or oxidianiline, ODA) and 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane (Methylenediamine), 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 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' -Dichlorobenzidine, 3,3'-dimethylbenzidine (or o-tolidine), 2,2'-dimethylbenzidine (or m-tolidine), 3,3'-dimethoxybenzidine, 2,2'-dimethoxy Benzidine, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenylsulfide, 3,4 ' -Diaminodiphenylsulfide, 4,4'-diamino Phenylsulfide, 3,3'-diaminodiphenylsulfone, 3,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, 3,3'-diaminobenzophenone, 4,4 ' -Diaminobenzophenone, 3,3'-diamino-4,4'-dichlorobenzophenone, 3,3'-diamino-4,4'-dimethoxybenzophenone, 3,3'-diaminodiphenyl Methane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 2,2-bis (3-aminophenyl) propane, 2,2-bis (4-amino Phenyl) 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'-diaminodiphenylsulfoxide, 3,4'-diaminodiphenylsulfoxide, 4,4'-diaminodiphenylsulfoxide Diamine having two benzene nuclei in structure;

3) 1,3-bis (3-aminophenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 1,4-bis (3-aminophenyl) benzene, 1,4-bis (4-amino Phenyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene (or TPE-Q), 1,4-bis (4-aminophenoxy) Benzene (or 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, which has three benzene nuclei in structure Amine;

4) 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 Si) 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-ami) Phenoxy) 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, 2,2-bis [4- (4-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, etc., Diamine having four benzene nuclei in structure.

These may be used alone or in combination of two or more as desired, but diamine monomers that can be particularly preferably used in the present invention include 1,4-diaminobenzene (PPD) and 1,3-diaminobenzene (MPD). ), 2,4-diaminotoluene, 2,6-diaminotoluene, and 3,5-diaminobenzoic acid (DABA).

2nd aspect: Manufacturing method of polyimide film and polyimide film

The method for producing a polyimide film according to the present invention,

(a) polymerizing one or more dianhydride monomers and one or more diamine monomers in an organic solvent to prepare a polyamic acid solution;

(b) a process of preparing a mixture by mixing an antioxidant in the polyamic acid solution;

(c) preparing a polyimide precursor composition by mixing the mixture with an aromatic carboxylic acid having 4 or more carboxyl groups; And

(d) forming a gel film by film-forming and drying the polyimide precursor composition on a support, and imidizing the gel film to produce a polyimide film,

The dianhydride monomer includes an adhesive dianhydride monomer represented by Formula 1 below,

The polyimide film is characterized in that the elongation is 13% or more.

(One)

In Chemical Formula 1, X ₁ and X ₂ may be each independently selected from the group consisting of C1-C3 alkyl group, aryl group, carboxyl group, hydroxy group, fluoroalkyl group, and sulfonic acid group,

When X ₁ and X ₂ are plural, they may be the same or different from each other,

n1 and n2 are each independently an integer of 0 to 3.

In Formula 1, when the substituent of the benzene ring is not specifically designated, it means hydrogen.

Preparation of a polyamic acid solution in the present invention, for example,

(1) A method in which the total amount of the diamine monomer is placed in a solvent, and then the dianhydride monomer is added to be substantially equimolar with the diamine monomer, followed by polymerization;

(2) a method in which the total amount of the dianhydride monomer is placed in a solvent, and then the diamine monomer is added to be substantially equimolar with the dianhydride monomer to polymerize;

(3) After adding some components of the diamine monomer in a solvent, after mixing some components of the dianhydride monomer with respect to the reaction component in a ratio of about 95 to 105 mol%, the remaining diamine monomer components are added thereto, followed by the rest A method of adding a dianhydride monomer component to polymerize the diamine monomer and the dianhydride monomer to be substantially equimolar;

(4) After placing the dianhydride monomer in a solvent, after mixing some components of the diamine compound with respect to the reaction component in a ratio of 95 to 105 mol%, another dianhydride monomer component is added and the rest of the diamine monomer component is continued. And a method in which the diamine monomer and the dianhydride monomer are substantially equimolar and polymerized;

(5) Some of the diamine monomer component and some of the dianhydride monomer component are reacted in an excess amount to form a first composition, and some of the diamine monomer component and some of the dianhydride monomer component are formed in another solvent. After the reaction is carried out so that the excess is formed to form a second composition, the first and second compositions are mixed and polymerization is completed. At this time, if the diamine monomer component is excessive when forming the first composition, the second composition In the dianhydride monomer component in excess, in the first composition when the dianhydride monomer component is excessive, in the second composition, the diamine monomer component in excess, the first and second compositions are mixed and used in these reactions So that the total diamine monomer component and the dianhydride monomer component become substantially equimolar It can be joined to the methods.

The organic solvent is not particularly limited as long as it is a solvent in which the polyamic acid can be dissolved, but as an example, the organic solvent may be an aprotic polar solvent.

Non-limiting examples of the aprotic polar solvent include amide solvents such as N, N'-dimethylformamide (DMF) and N, N'-dimethylacetamide (DMAc), p-chlorophenol, and o-chloro And phenol-based solvents such as phenol, N-methyl-pyrrolidone (NMP), gamma brotirolactone (GBL) and digrime, and these may be used alone or in combination of two or more.

In some cases, the solubility of the polyamic acid may be controlled by using auxiliary solvents such as toluene, tetrahydrofuran, acetone, methyl ethyl ketone, methanol, ethanol, and water.

In one example, organic solvents that can be particularly preferably used for preparing the polyimide precursor composition of the present invention may be amide solvents N, N'-dimethylformamide and N, N'-dimethylacetamide.

The polymerization method is not limited to the above examples, and it is needless to say that any known method can be used.

The dianhydride monomer may be appropriately selected from the examples described above, and in detail, pyromellitic dianhydride (PMDA), 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride (s-BPDA) and 2,3,3 ', 4'-biphenyltetracarboxylic dianhydride (a-BPDA) may further include one or more selected from the group consisting of.

The diamine monomer may be appropriately selected from the examples described above, and specifically, 1,4-diaminobenzene (PPD), 1,3-diaminobenzene (MPD), 2,4-diaminotoluene, 2, One or more selected from the group consisting of 6-diaminotoluene and 3,5-diaminobenzoic acid (DABA) can be preferably used.

The process (a) is carried out at 30 to 80 ℃,

The polyamic acid solution may have a viscosity at 23 ° C of 1,000 to 20,000 cP.

In addition, the process (b) is a silicone-based additive, an alkoxy silane coupling agent is further mixed in a polyamic acid solution, and is performed at 40 to 90 ° C

The process (c) is carried out at 40 to 90 ℃,

In the process (d), the polyimide precursor composition formed on the support is dried at a temperature of 20 to 120 ° C. for 5 to 60 minutes to prepare a gel film, and the gel film is 1 to 8 ° C. to 450 to 500 ° C. / It can be carried out through a process of heating at a rate of minutes, heat treatment at 450 to 500 ° C for 30 to 60 minutes, and cooling at 20 to 120 ° C at a rate of 1 to 8 ° C / minute.

The support may be, for example, an inorganic substrate, and examples of the inorganic substrate include a glass substrate and a metal substrate, but it is preferable to use a glass substrate, and the glass substrate is soda-lime glass, borosilicate glass, and alkali-free glass. And the like may be used, but is not limited to this.

On the other hand, in the gel film state, since it is not easy to directly measure the adhesive force between the gel film and the support, the adhesive force between the polyimide film and the support prepared from the gel film is measured to indirectly evaluate the adhesive force between the gel film and the support. Can be. This is because the polyimide film prepared from the gel film can be expected to exhibit similar properties in adhesion to the support.

Specifically, the adhesive force between the polyimide film and the support may be 0.3 N / cm or more, and in particular, 0.5 to 1 N / cm.

That is, by including the adhesive dianhydride monomer in the process (a), in the process (d), the adhesive force between the gel film and the support is improved, the gel film is rolled up or partly peeled off the support It can minimize the lifting phenomenon.

In addition, the aromatic carboxylic acid contained in the polyimide precursor composition is not polymerized with polyamic acid in step (c), but the polyimide precursor is formed by increasing the length of the polyimide chain during heat treatment for imidization. In the process, since the process viscosity is good due to the low viscosity, and then the length of the polymer chain is increased in the curing process, it is possible to secure a level of heat resistance and mechanical properties similar to that of a polyimide film made from polyamic acid having a higher molecular weight. .

In the production method of the present invention, the polyimide film may be produced through a thermal imidization method, and chemical imidization method may be performed in parallel.

The thermal imidization method is a method of excluding chemical catalysts and inducing an imidization reaction with a heat source such as hot air or an infrared dryer.

The thermal imidization method may be included in the process (d), and the amic acid group present in the gel film is imidized by heat-treating the gel film at a variable temperature in the range of 100 to 600 ° C in the process (d). It can be made, and in detail, heat treatment at 200 to 500 ° C, and more specifically, 450 to 500 ° C, can imidize the amic acid group present in the gel film.

However, even in the process of forming the gel film, some of the amic acid (about 0.1 mol% to 10 mol%) may be imidized, and for this, in the process of forming the gel film, the range of 50 ° C to 200 ° C is variable. The polyimide precursor composition may be dried at a phosphorus temperature, which may also be included in the scope of the thermal imidization method.

The polyimide film of the present invention prepared according to the above manufacturing method has a thermal expansion coefficient (CTE) of 1 to 25 ppm / ° C, an elongation of 13% or more, and a thermal decomposition temperature of 1% by weight of 555 to 620 ° C. , Glass transition temperature is 380 ℃ or more, the modulus is 8 GPa or more, the tensile strength is 280 MPa or more, the thickness may be 10 to 20 ㎛.

When the chemical imidization method is used in parallel, a polyimide film may be prepared using a dehydrating agent and an imidizing agent according to methods known in the art.

The present invention can also provide an electronic device including the polyimide film.

Hereinafter, the operation and effects of the invention will be described in more detail through specific examples of the invention. However, these examples are only presented as examples of the invention, and the scope of the invention is not thereby determined.

The abbreviated compound names used in Examples and Comparative Examples are as follows.

-Biphenyltetracarboxylic dianhydride: BPDA

-Pyromelitic dianhydride: PMDA

-Biphenyltetracarboxylic acid: BPTA

-Para-phenylene diamine: p-PDA

-N-methyl pyrrolidone: NMP

<Example 1>

After injecting nitrogen into a 500 ml reactor equipped with a stirrer and a nitrogen injection / discharge tube, NMP was introduced and the temperature of the reactor was set to 30 ° C, followed by p-PDA as a diamine monomer, BPDA as a dianhydride monomer, and adhesive dianhydride. BTDA was added as a monomer to confirm complete dissolution. After heating the mixture to a temperature of 40 ° C. under a nitrogen atmosphere and stirring was continued for 120 minutes, a polyamic acid solution having a viscosity at 23 ° C. of 6100 cP was prepared.

After setting the temperature of the reactor to 50 ° C, BYK-378 as a silicon-based additive to the polyamic acid solution, OFS- as a compound of Formula 2-1 having a 5 wt% decomposition temperature of about 402 ° C as an antioxidant, an alkoxy silane coupling agent 6011 was added at a weight ratio of 1: 50: 1 and stirred slowly for 30 minutes to prepare a mixed solution containing a silicone-based additive, an antioxidant, and an alkoxy silane coupling agent.

(2-1)

After setting the temperature of the reactor to 50 ° C, 0.5 mol of BPTA was added to 100 mol of p-PDA to the mixed solution. The mixture was sufficiently stirred until the reaction was completed, and NMP was added so that the total solid content was about 15% by weight and the viscosity was about 5,100 cP, and diamine monomer, dianhydride monomer, aromatic carboxylic acid, and adhesive dianhydride were added. A polyimide precursor composition was prepared having a molar ratio of 100: 98.5: 0.5: 1, 0.01 parts by weight of a silicone-based additive, 0.5 parts by weight of an antioxidant, and 0.01 parts by weight of an alkoxy silane coupling agent based on 100 parts by weight of solids.

Air bubbles were removed from the polyimide precursor composition through high-speed rotation of 1,500 rpm or more. Thereafter, the defoamed polyimide precursor composition was applied to a glass substrate using a spin coater. Then, under a nitrogen atmosphere and dried at a temperature of 120 ° C. for 30 minutes, a gel film was prepared. Cooling at a rate of 2 ° C / min yielded a polyimide film.

Thereafter, the polyimide film was peeled from the glass substrate by dipping in distilled water. The thickness of the prepared polyimide film was 15 μm. The thickness of the prepared polyimide film was measured using an Anritsu company's film thickness meter (Electric Film thickness tester).

<Examples 2 to 11 and Comparative Examples 1 to 12, 15 to 19>

In Example 1, a polyimide film was prepared in the same manner as in Example 1, except that the viscosity of the monomer, additive, and polyimide precursor composition was changed as shown in Table 1 below.

<Comparative Example 13>

In Example 1, a polyimide film was prepared in the same manner as in Example 1, except that instead of the compound of Formula 2-1 as an antioxidant, a compound of Formula A having a 5 wt% decomposition temperature of about 377 ° C was added. .

(A)

<Comparative Example 14>

In Example 1, a polyimide film was prepared in the same manner as in Example 1, except that the compound of Formula B having a 5 wt% decomposition temperature of about 338 ° C. instead of the compound of Formula 2-1 as an antioxidant was added. .

(B)

	p-PDA (mol%)	BPDA (mol%)	PMDA (mol%)	BPTA (mol%)	BTDA (mol%)	Antioxidant		Coupling agent (parts by weight)	Silicone additives (parts by weight)	Viscosity (cP)
						Kinds	Content (parts by weight)
Example 1	100	98.5	-	0.5	One	Formula 2-1	0.1	0.1	0.1	5,100
Example 2	100	94.5	-	0.5	5	Formula 2-1	0.1	0.1	0.1	5,100
Example 3	100	97.5	-	0.5	2	Formula 2-1	0.1	0.1	0.1	5,100
Example 4	100	97	-	2	One	Formula 2-1	0.1	0.1	0.1	5,100
Example 5	100	98.5	-	0.5	One	Formula 2-1	0.5	0.1	0.1	5,100
Example 6	100	98.5	-	0.5	One	Formula 2-1	0.1	0.5	0.1	5,100
Example 7	100	98.5	-	0.5	One	Formula 2-1	0.1	0.1	0.5	5,100
Example 8	100	50	48.5	0.5	One	Formula 2-1	0.1	0.1	0.1	4,900
Example 9	100	50	44.5	0.5	5	Formula 2-1	0.1	0.1	0.1	4,900
Example 10	100	50	47	2	One	Formula 2-1	0.1	0.1	0.1	4,900
Example 11	100	50	48.5	0.5	One	Formula 2-1	0.5	0.1	0.1	4,900
Comparative Example 1	100	99.5	-	0.5	-	Formula 2-1	0.1	0.1	0.1	5,100
Comparative Example 2	100	92	-	0.5	0.5	Formula 2-1	0.1	0.1	0.1	5,100
Comparative Example 3	100	92	-	0.5	6	Formula 2-1	0.1	0.1	0.1	5,100
Comparative Example 4	100	99	-	-	One	Formula 2-1	0.1	0.1	0.1	5,100
Comparative Example 5	100	93	-	6	One	Formula 2-1	0.1	0.1	0.1	5,100
Comparative Example 6	100	98.5	-	0.5	One	Formula 2-1	0.1	-	0.1	5,100
Comparative Example 7	100	98.5	-	0.5	One	Formula 2-1	0.1	0.1	-	5,100
Comparative Example 8	100	98.5	-	0.5	One	Formula 2-1	0.1	0.6	0.1	5,100
Comparative Example 9	100	98.5	-	0.5	One	Formula 2-1	0.1	0.1	0.6	5,100
Comparative Example 10	100	98.5	-	0.5	One	-	-	0.1	0.1	5,100
Comparative Example 11	100	98.5	-	0.5	One	Formula 2-1	0.01	0.1	0.1	5,100
Comparative Example 12	100	98.5	-	0.5	One	Formula 2-1	2	0.1	0.1	5,100
Comparative Example 13	100	98.5	-	0.5	One	Formula A	0.1	0.1	0.1	5,100
Comparative Example 14	100	98.5	-	0.5	One	Formula B	0.1	0.1	0.1	5,100
Comparative Example 15	100	50	49.5	0.5	-	Formula 2-1	0.1	0.1	0.1	4,900
Comparative Example 16	100	50	49	-	One	Formula 2-1	0.1	0.1	0.1	4,900
Comparative Example 17	100	50	48.5	0.5	One	-	-	0.1	0.1	4,900
Comparative Example 18	100	100	-	-	-	Formula 2-1	0.1	0.1	0.1	25,000
Comparative Example 19	100	50	50	-	-	Formula 2-1	0.1	0.1	0.1	25,000

<Experimental Example 1: Evaluation of adhesive strength>

For the polyimide films prepared in Examples 1 to 11 and Comparative Examples 1 to 19, an adhesive force with a glass substrate was measured using a tensile tester (Instron5564), and the results are shown in Table 2 below.

Specifically, for the polyimide film obtained in Examples, before peeling the polyimide film from the glass substrate, it was cut to a width of 10 mm using a cutter knife, under a condition of 23 ° C., 55% RH, and a tensile speed of 50 m / min. In the case of 50 mm 뗐, the average value of the 180 degree peel strength was measured.

<Experimental Example 2: Property evaluation>

The physical properties of the polyimide films prepared in Examples 1 to 11 and Comparative Examples 1 to 19 were measured using the following method, and the results are shown in Table 2 below.

(1) Coefficient of thermal expansion (CTE)

A TA thermomechanical analyzer Q400 model was used, and the polyimide film was cut to a width of 2 mm and a length of 10 mm, and then subjected to a tension of 0.05 N under a nitrogen atmosphere, at a rate of 10 ° C./min, 500 at room temperature. After heating up to ℃, while cooling at a rate of 10 ℃ / min again, the slope of the section at 100 ℃ to 350 ℃ was measured.

(2) Elongation

After the polyimide film was cut to a width of 10 mm and a length of 40 mm, elongation was measured by an ASTM D-882 method using Instron5564 UTM equipment manufactured by Instron.

(3) Thermal decomposition temperature (TD) of 1% by weight

A TA thermogravimetric analysis Q50 model was used, and the polyimide film was heated to 150 ° C. at a rate of 10 min / ° C. under a nitrogen atmosphere to maintain isotherm for 30 minutes to remove moisture. Thereafter, the temperature was raised to 600 ° C at a rate of 10 min / ° C, and the temperature at which 1% weight loss occurred was measured.

(4) Glass transition temperature (Tg)

Using the Q800 model of the TA Dynamic Mechanical Analysis, the polyimide film was cut to a width of 4 mm and a length of 20 mm, and then heated at a rate of 5 ° C./min under a nitrogen atmosphere and a temperature range of 550 ° C. at room temperature. The glass transition temperature was measured under conditions. The glass transition temperature was determined as the maximum peak of tanδ calculated according to the ratio of storage modulus and loss modulus.

(5) Modulus and tensile strength

After cutting the polyimide film to a width of 10 mm and a length of 40 mm, modulus and tensile strength were measured by ASTM D-882 method using Instron5564 UTM equipment of Instron. The cross head speed at this time was measured under the condition of 5 mm / min.

	Adhesion (N / cm)	CTE (ppm / ℃)	Elongation (%)	TD (℃)	Tg (℃)	Modulus (GPa)	Tensile strength (MPa)
Example 1	0.35	22	18	565	410	9.1	320
Example 2	0.55	20	16	560	407	8.8	310
Example 3	0.40	18	20	563	408	9.0	333
Example 4	0.30	15	20	560	405	9.0	330
Example 5	0.33	18	22	570	420	8.9	340
Example 6	0.40	16	18	560	405	8.9	324
Example 7	0.42	20	20	558	395	8.8	328
Example 8	0.38	12	15	570	440	9.5	293
Example 9	0.56	13	13	565	435	9.6	285
Example 10	0.33	9	17	563	430	9.4	317
Example 11	0.35	5	15	565	445	9.7	290
Comparative Example 1	0.07	22	10	554	378	7.8	275
Comparative Example 2	0.10	21	9	550	375	7.7	270
Comparative Example 3	0.27	25	7	545	368	7.5	264
Comparative Example 4	0.28	28	9	553	370	7.7	272
Comparative Example 5	0.25	30	8	550	360	7.5	268
Comparative Example 6	0.25	20	11	554	378	7.9	274
Comparative Example 7	0.26	20	9	553	378	7.8	270
Comparative Example 8	0.26	18	8	549	370	6.8	266
Comparative Example 9	0.26	18	8	548	370	6.7	262
Comparative Example 10	0.28	20	10	550	368	7.4	267
Comparative Example 11	0.28	20	11	552	370	7.6	270
Comparative Example 12	0.25	24	8	545	355	6.9	255
Comparative Example 13	0.24	23	11	554	378	7.9	275
Comparative Example 14	0.24	23	10	549	370	7.8	271
Comparative Example 15	0.06	10	7	553	378	7.1	252
Comparative Example 16	0.26	15	11	557	375	7.8	278
Comparative Example 17	0.25	10	10	548	365	7.7	270
Comparative Example 18	0.05	50	10	555	355	7.9	277
Comparative Example 19	0.04	30	5	550	355	6.8	246

Referring to Table 2, in the case of embodiments satisfying the scope of the present invention, it can be confirmed that adhesive strength, heat resistance, and mechanical properties are all excellent. On the other hand, it can be confirmed that the comparative examples outside the scope of the present invention do not satisfy at least one of adhesion, heat resistance, and mechanical properties.

Although described above with reference to the embodiments of the present invention, those skilled in the art to which the present invention pertains will be able to perform various applications and modifications within the scope of the present invention based on the above.

The polyimide precursor composition according to the present invention comprises an adhesive dianhydride monomer, thereby forming a gel film by forming a polyimide precursor composition on a support and drying the gel film and the support in the process of imidizing the gel film. It is possible to improve the production yield by improving the adhesion.

In addition, aromatic carboxylic acids having 4 or more carboxyl groups included in the polyimide precursor composition have good process handling properties due to low viscosity, and since the length of the polymer chain is increased in the curing process after being formed, from polyamic acids having higher molecular weight It is possible to secure a level of heat resistance and mechanical properties similar to those of the produced polyimide film.

In addition, an antioxidant having a 5 wt% decomposition temperature of 380 ° C or higher included in the polyimide precursor composition has low volatility and excellent thermal stability, and thus does not decompose or volatilize during the production process of the polyimide film, and the amide in the polyimide precursor composition The oxidation of the imide group of the group or the polyimide film can be prevented, thereby minimizing the change in physical properties of the polyimide film.

The polyimide film has an advantage of satisfying the heat resistance and mechanical properties required for the display substrate.

Claims (21)

A polyamic acid solution prepared by polymerizing one or more dianhydride monomers and one or more diamine monomers in an organic solvent;

Aromatic carboxylic acids having 4 or more carboxyl groups; And

Contains antioxidants,

The dianhydride monomer includes an adhesive dianhydride monomer represented by the following Chemical Formula 1,

A polyimide precursor composition having an elongation of 13% or more of the polyimide film prepared therefrom:

(One)

In Chemical Formula 1, X ₁ and X ₂ may be each independently selected from the group consisting of C1-C3 alkyl group, aryl group, carboxyl group, hydroxy group, fluoroalkyl group, and sulfonic acid group,

When X ₁ and X ₂ are plural, they may be the same or different from each other,

n1 and n2 are each independently an integer of 0 to 3.

According to claim 1,

The adhesive dianhydride monomer is 2,3,3 ', 4'- benzophenone tetracarboxylic dianhydride, 3,3', 4,4'-benzophenone tetracarboxylic dianhydride (BTDA) A polyimide precursor composition comprising at least one selected from the group consisting of.

According to claim 1,

The aromatic carboxylic acid is 3,3 ', 4,4'-biphenyltetracarboxylic acid (3,3', 4,4'-biphenyltetracarboxylic acid, BPTA), pyromellitic acid (PMA), 1, 2,3,4-benzenetetracarboxylic acid, benzophenone-3,3 ', 4,4'-tetracarboxylic acid (benzophenone-3,3', 4,4 '-tetracarboxylic acid, pyrazinetetracarboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid (2,3,6,7-naphthalenetetracarboxylic acid) and naphthalene-1,4,5,8- A polyimide precursor composition comprising at least one member selected from the group consisting of tetracarboxylic acids (naphthalene-1,4,5,8-tetracarboxylic acid).

According to claim 1,

Based on 100 mol% of the diamine monomer, the content of the dianhydride monomer is 93 to 98.8 mol%, the content of the adhesive dianhydride monomer is 1 to 5 mol%, and the aromatic having 4 or more carboxyl groups A polyimide precursor composition having a carboxylic acid content of 0.2 to 2 mol%.

According to claim 1,

The antioxidant is a polyimide precursor composition having a 5 wt% decomposition temperature of 380 ° C or higher.

The method of claim 5,

The antioxidant is 5% by weight decomposition temperature of 400 ℃ or more, polyimide precursor composition.

According to claim 1,

The antioxidant, a polyimide precursor composition comprising a compound represented by the following formula (2):

(2)

In Chemical Formula 2, R ₁ to R ₆ may each independently be selected from the group consisting of C1-C3 alkyl groups, aryl groups, carboxyl groups, hydroxy groups, fluoroalkyl groups, and sulfonic acid groups,

n is an integer from 1 to 4,

When R ₁ to R ₆ are plural, they may be the same or different from each other,

m1 to m6 are each independently an integer of 0 to 3.

The method of claim 7,

In Formula 2, n is 1 and m1 to m6 are 0, a polyimide precursor composition.

According to claim 1,

A polyimide precursor composition comprising 0.1 to 2 parts by weight of an antioxidant with respect to 100 parts by weight of the solid content of the polyimide precursor composition.

According to claim 1,

The polyimide precursor composition, the polyimide precursor composition further comprises a silicone-based additive.

The method of claim 10,

A polyimide precursor composition comprising 0.01 to 0.05 parts by weight of a silicone-based additive with respect to 100 parts by weight of the solid content of the polyimide precursor composition.

The method of claim 11,

The silicone additives include dimethylpolysiloxane, polyether modified polydimethysiloxane polymethylalkylsiloxane, and hydroxyl group (-OH) and carbon-carbon double bond structure (C = C). A polyimide precursor composition comprising one or more selected from the group consisting of silicon-based compounds.

According to claim 1,

The polyimide precursor composition further comprises an alkoxy silane coupling agent.

The method of claim 13,

A polyimide precursor composition comprising 0.01 to 0.05 parts by weight of an alkoxy silane coupling agent with respect to 100 parts by weight of solid content of the polyimide precursor composition.

The method of claim 13,

The alkoxy silane coupling agent is 3-aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, 3-aminopropyl methyl dimethoxysilane, 3-aminopropyl methyl diethoxysilane, 3- (2-aminoethyl) A polyimide precursor comprising at least one member selected from the group consisting of aminopropyl trimethoxysilane, 3-phenylaminopropyl trimethoxysilane, 2-aminophenyl trimethoxysilane, and 3-aminophenyl trimethoxysilane. Composition.

A polyimide film prepared from the polyimide precursor composition of claim 1.

The method of claim 16,

The polyimide film has a thermal decomposition temperature of 1% by weight is 555 to 620 ° C,

Glass transition temperature is 380 ℃ or higher,

Modulus is 8 GPa or more,

Tensile strength is more than 280 MPa,

The coefficient of thermal expansion (CTE) is 1 to 25 ppm / ° C,

A polyimide film having a thickness of 10 to 20 μm.

(a) polymerizing one or more dianhydride monomers and one or more diamine monomers in an organic solvent to prepare a polyamic acid solution;

(b) a process of preparing a mixture by mixing an antioxidant in the polyamic acid solution;

(c) preparing a polyimide precursor composition by mixing the mixture with an aromatic carboxylic acid having 4 or more carboxyl groups; And

(d) forming a gel film by film-forming and drying the polyimide precursor composition on a support, and imidizing the gel film to produce a polyimide film,

The dianhydride monomer includes an adhesive dianhydride monomer represented by Formula 1 below,

The polyimide film has an elongation of 13% or more, a method for producing a polyimide film:

(One)

In Chemical Formula 1, X ₁ and X ₂ may be each independently selected from the group consisting of C1-C3 alkyl group, aryl group, carboxyl group, hydroxy group, fluoroalkyl group, and sulfonic acid group,

When X ₁ and X ₂ are plural, they may be the same or different from each other,

n1 and n2 are each independently an integer of 0 to 3.

The method of claim 18,

The process (b) comprises a process of further mixing a silicone-based additive and an alkoxy silane coupling agent in a polyamic acid solution, a method for producing a polyimide film.

The method of claim 18,

The method of manufacturing a polyimide film, wherein the adhesion between the polyimide film and the support is 0.3 N / cm or more.

An electronic device comprising the polyimide film according to claim 16.