KR20200008006A - Polyamide-imide film and preparation method thereof - Google Patents

Abstract

An embodiment relates to: a polyamide-imide film which can be useful in the field of flexible displays because of the high elongation and excellent flexibility thereof; and to a method of manufacturing the polyamide-imide film. The polyamide-imide film includes a repeating unit represented by formula A and a repeating unit represented by formula B.

Description

Polyamide-imide film and its manufacturing method {POLYAMIDE-IMIDE FILM AND PREPARATION METHOD THEREOF}

The embodiment relates to a polyamide-imide film and a method of manufacturing the same that can be usefully used in the field of flexible displays because of its high elongation and excellent flexibility.

Polyamide-imide (PAI) has excellent friction, heat, and chemical resistance, so it can be used as primary electrical insulation, coating, adhesive, extrusion resin, heat-resistant paint, heat-resistant plate, heat-resistant adhesive, heat-resistant fiber, And heat-resistant films.

Polyamide-imide is used in various fields. For example, polyamide-imide is made in powder form and used as a coating agent such as metal or magnetic wire, and is mixed with other additives depending on the use. In addition, polyamide-imide is used as a paint for decoration and corrosion protection together with the fluoropolymer, and serves to adhere the fluoropolymer to the metal substrate. Polyamide-imide is also used as a coating for kitchen cooking utensils, and as a membrane used for gas separation due to its heat resistance and chemical resistance, and to filter contaminants such as carbon dioxide, hydrogen sulfide and impurities from natural gas wells. It is also used for devices.

In recent years, polyamide-imide films have been developed, and thus, polyamide-imide films having low cost and excellent optical, mechanical and thermal properties have been developed.

The embodiment is to provide a polyamide-imide film and a method for manufacturing the same that can be usefully used in the field of flexible (flexible) display because of its high elongation and excellent flexibility.

The polyamide-imide film according to one embodiment includes a repeating unit represented by the following Formula A and a repeating unit represented by the following Formula B:

<Formula A>

<Formula B>

In Formulas A and B,

E and J are, independently from each other, a substituted or unsubstituted divalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted divalent C ₆ -C ₃₀ aromatic ring group, substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaromatic ring group, substituted or unsubstituted C ₁ -C ₃₀ alkylene group, substituted or unsubstituted C ₂ -C ₃₀ alkenylene group , Substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-, -S-, -C (= O)-, -CH (OH)-, -S (= O) _2- , -Si ( CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) _2- ,

e and j are each independently selected from an integer of 1 to 5,

when e is 2 or more, two or more E are the same as or different from each other,

when j is 2 or more, two or more J are the same as or different from each other,

G is a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aromatic ring group , A substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaromatic ring group, wherein the aliphatic ring group, the heteroaliphatic ring group, the aromatic ring group or the heteroaromatic ring group are present alone, or are bonded to each other to form a condensed ring Form a substituted or unsubstituted C ₁ -C ₃₀ alkylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkenylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-,- S-, -C (= 0)-, -CH (OH)-, -S (= 0) _2- , -Si (CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) ₂ -are connected by the connector selected from

The repeating unit represented by the formula (B) includes two or more different repeating units,

At least one of the two or more repeating units includes a group in which (J) _j comprises -O-,

At least one of the two or more repeating units includes a group in which (J) _j does not contain -O-.

According to another embodiment, a method of preparing a polyamide-imide film may include preparing a polyamide-imide polymer solution including a repeating unit represented by Formula A and a repeating unit represented by Formula B; Introducing the polymer solution into a tank; Extruding and casting the polymer solution in the tank and drying to prepare a gel sheet; And heat treating the gel sheet.

The polyamide-imide film according to the embodiment has a high elongation and thus has excellent flexibility, so that the polyamide-imide film may be usefully used in the field of flexible displays, and also has excellent optical and mechanical properties.

According to the method for producing a polyamide-imide film according to the embodiment, it is possible to provide a film having high elongation and excellent optical and mechanical properties.

Hereinafter, the present invention will be described in detail through examples. The embodiments may be modified in various forms unless the gist of the invention is changed.

"Including" in the present specification means that it may further include other components unless otherwise specified.

In addition, all numbers and expressions indicating the amounts of ingredients, reaction conditions, and the like described herein are to be understood as being modified in all instances by the term "about" unless otherwise specified.

In addition, the term "substituted" in this specification, unless otherwise specified, deuterium, -F, -Cl, -Br, -I, hydroxyl group, cyano group, nitro group, amino group, amidino group, hydrazine group, Hydrazone group, ester group, ketone group, carboxyl group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted alkynyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted alicyclic oil Means substituted with one or more substituents selected from the group consisting of a device, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted aryl group and a substituted or unsubstituted heteroaryl group, the substituents listed above are linked to each other It means that it can form a ring.

In the present specification, terms such as first and second are used to describe various components, and the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component into another.

[ Polyamide -Imide film]

The embodiment provides a film having high elongation and also excellent optical and mechanical properties.

The polyamide-imide film according to one embodiment includes a repeating unit represented by the following Formula A and a repeating unit represented by the following Formula B:

<Formula A>

<Formula B>

In Formulas A and B,

E and J are, independently from each other, a substituted or unsubstituted divalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted divalent C ₆ -C ₃₀ aromatic ring group, substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaromatic ring group, substituted or unsubstituted C ₁ -C ₃₀ alkylene group, substituted or unsubstituted C ₂ -C ₃₀ alkenylene group , Substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-, -S-, -C (= O)-, -CH (OH)-, -S (= O) _2- , -Si ( CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) _2- ,

e and j are each independently selected from an integer of 1 to 5,

when e is 2 or more, two or more E are the same as or different from each other,

when j is 2 or more, two or more J are the same as or different from each other,

G is a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aromatic ring group , A substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaromatic ring group, wherein the aliphatic ring group, the heteroaliphatic ring group, the aromatic ring group or the heteroaromatic ring group are present alone, or are bonded to each other to form a condensed ring Form a substituted or unsubstituted C ₁ -C ₃₀ alkylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkenylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-,- S-, -C (= 0)-, -CH (OH)-, -S (= 0) _2- , -Si (CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) ₂ -are connected by the connector selected from

The repeating unit represented by the formula (B) includes two or more different repeating units,

At least one of the two or more repeating units includes a group in which (J) _j comprises -O-,

At least one of the two or more repeating units includes a group in which (J) _j does not contain -O-.

The repeating unit represented by the formula (A) is an imide repeating unit derived from the polymerization of the diamine compound and the dianhydride compound, and the repeating unit represented by the formula (B) is derived from the polymerization of the diamine compound and the dicarbonyl compound. Is an amide repeating unit.

The repeating unit represented by Formula A and the repeating unit represented by Formula B are repeating units included in the polyamide-imide polymer.

That is, the polyamide-imide film includes a polyamide-imide polymer formed by polymerizing a diamine compound, a dianhydride compound, and a dicarbonyl compound, and the polyamide-imide polymer is represented by Chemical Formula A. It includes a repeating unit and a repeating unit represented by the formula (B).

The molar ratio of the repeating unit represented by Formula A and the repeating unit represented by Formula B included in the polyamide-imide film may be 20:80 to 80:20. Specifically, the molar ratio of the repeating unit represented by Formula A and the repeating unit represented by Formula B is 30:70 to 80:20, 40:60 to 80:20, 50:50 to 80:20, 50:50 To 70:30, 55:45 to 70:30, or 55:45 to 65:35, and more specifically, to 60:40, but is not limited thereto.

When the molar ratio of the repeating unit represented by the formula (A) and the repeating unit represented by the formula (B) is within the above range, the optical and mechanical properties of the film, such as transmittance and haze, are excellent.

In Formulas A and B, (E) _e may be selected from the group represented by Formulas 1-1a to 1-14a:

Specifically, (E) _e may be selected from the group represented by the following Chemical Formulas 1-1b to 1-13b, but is not limited thereto:

More specifically, (E) _e may include a group represented by Formula 1-7a. (E) _e may be formed of a group represented by Formula 1-7a.

Alternatively, (E) _e may include a group represented by Chemical Formula 1-6b. (E) _e may be formed of a group represented by Formula 1-6b.

In Formula A, G may be selected from the group represented by Formulas 2-1a to 2-9a:

More specifically, the G may include a group represented by 2-8a. G may be composed of a group represented by 2-8a.

In Formula B, (J) _j is a group represented by Formula 3-10a; And selected from the group represented by the formula 3-1a to 3-9a and 3-11a to 3-14a; may include, but are not limited to:

Specifically, (J) _j is a group represented by the following formula 3-4b or 3-5b; And selected from the group represented by the formula 3-1b to 3-3b and 3-6b to 3-8b; may include, but is not limited thereto.

In the formulas (A) and (B), at least one of (E) _e and G is a group containing fluorine.

Alternatively, in Formulas (A) and (B), (E) _e and G are both groups containing fluorine.

The fluorine-containing group may be a group containing a fluorinated hydrocarbon group, specifically, a trifluoromethyl group, but is not limited thereto.

The repeating unit represented by Formula B includes at least two repeating units different from each other. In addition, the repeating unit represented by the formula (B) consists of two different repeating units.

At least one of the two or more repeating units includes a group in which (J) _j includes -O-, and at least one of the two or more repeating units does not include (J) _j containing -O-. Include a group.

Further, the group of repeating units in the molar ratio of the repeating unit (J) _j group does not contain a -O-, which is the repeating unit (J) _j represented by the formula B include -O- is 20: 80 to 80:20 or 25:75 to 75:25. In this case, a high elongation characteristic can be implemented.

By satisfying the above characteristics, it is possible to realize a film having a high elongation without compromising the optical properties of the film, and since such a film is excellent in flexibility, it can be usefully used in the field of flexible displays.

Specifically, the repeating unit represented by Formula A may include a repeating unit represented by Formula A-1.

<Formula A-1>

N in Chemical Formula A-1 is an integer of 1 to 400.

In addition, the repeating unit represented by Formula B may include a repeating unit represented by Formula B-1 and a repeating unit represented by Formula B-2.

<Formula B-1>

X in Chemical Formula B-1 is an integer of 1 to 400.

<Formula B-2>

Y in Formula B-2 is an integer of 1 to 400.

The diamine compound is a compound which imide-bonds with the dianhydride compound and an amide bond with the dicarbonyl compound to form a copolymer.

The diamine compound is a compound represented by the following formula (1).

<Formula 1>

In Formula 1,

E is a substituted or unsubstituted divalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted divalent C ₆ -C ₃₀ aromatic ring group , Substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaromatic ring group, substituted or unsubstituted C ₁ -C ₃₀ alkylene group, substituted or unsubstituted C ₂ -C ₃₀ alkenylene group, substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-, -S-, -C (= O)-, -CH (OH)-, -S (= O) _2- , -Si (CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) ₂ -may be selected.

e is selected from an integer of 1 to 5, and when e is 2 or more, E may be the same or different from each other.

Description of (E) _e in the formula (1) is as described above.

The diamine compound may be an aromatic diamine.

In addition, the diamine compound may include a compound having a fluorine-containing substituent. Alternatively, the diamine compound may be formed of a compound having a fluorine-containing substituent. In this case, the fluorine-containing substituent may be a fluorinated hydrocarbon group, specifically may be a trifluoromethyl group, but is not limited thereto.

For example, the diamine compound has 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl (2,2'-Bis (trifluoromethyl) -4,4 having a structure as follows. '-diaminodiphenyl, TFDB), but is not limited thereto.

Since the dianhydride compound has a low birefringence value, the dianhydride compound is a compound capable of contributing to improvement of optical properties such as transmittance of the polyamide-imide film.

The dianhydride compound is a compound represented by the following formula (2).

<Formula 2>

In Formula 2,

G is a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aromatic ring group , A substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaromatic ring group, wherein the aliphatic ring group, the heteroaliphatic ring group, the aromatic ring group or the heteroaromatic ring group are present alone, or are bonded to each other to form a condensed ring Form a substituted or unsubstituted C ₁ -C ₃₀ alkylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkenylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-,- S-, -C (= 0)-, -CH (OH)-, -S (= 0) _2- , -Si (CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) ₂ -is connected by a connector selected from.

Description of the G in Formula 3 is as described above.

The dianhydride compound may be an aromatic dianhydride compound.

In addition, the dianhydride compound may include a compound having a fluorine-containing substituent. Alternatively, the dianhydride compound may be formed of a compound having a fluorine-containing substituent. In this case, the fluorine-containing substituent may be a fluorinated hydrocarbon group, specifically may be a trifluoromethyl group, but is not limited thereto.

For example, the dianhydride compound may have 2,2'-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride (2,2'-Bis- (3,4) having a structure as follows. -Dicarboxyphenyl) hexafluoropropane dianhydride, 6-FDA), but is not limited thereto.

The diamine compound and the dianhydride compound may be polymerized to produce a polyamic acid.

Subsequently, the polyamic acid may be converted into a polyimide through a dehydration reaction, and the polyimide includes an imide repeat unit.

The polyimide may form a repeating unit represented by Formula A below.

<Formula A>

In the formula (A), the description of E, G and e is as described above.

For example, the polyimide may include a repeating unit represented by Chemical Formula A-1, but is not limited thereto.

<Formula A-1>

N in Chemical Formula A-1 is an integer of 1 to 400.

The dicarbonyl compound is a compound represented by the following formula (3).

<Formula 3>

In Formula 3,

J is a substituted or unsubstituted divalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted divalent C ₆ -C ₃₀ aromatic ring group , Substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaromatic ring group, substituted or unsubstituted C ₁ -C ₃₀ alkylene group, substituted or unsubstituted C ₂ -C ₃₀ alkenylene group, substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-, -S-, -C (= O)-, -CH (OH)-, -S (= O) _2- , -Si (CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) ₂ -may be selected.

j is selected from an integer of 1 to 5, and when j is 2 or more, J may be the same or different from each other.

X is a halogen atom. Specifically, X may be F, Cl, Br, I and the like. More specifically, X may be Cl, but is not limited thereto.

In the said Formula (3), description about (J) _j is as above-mentioned.

The dicarbonyl compound may include at least two different dicarbonyl compounds. In addition, the dicarbonyl compound may be composed of two different dicarbonyl compounds.

The dicarbonyl compound may be an aromatic dicarbonyl compound.

For example, the dicarbonyl compound may include a first dicarbonyl compound and / or a second dicarbonyl compound.

The first dicarbonyl compound and the second dicarbonyl compound may be aromatic dicarbonyl compounds.

The first dicarbonyl compound and the second dicarbonyl compound may be different compounds from each other.

For example, the first dicarbonyl compound and the second dicarbonyl compound may be different aromatic dicarbonyl compounds from each other, but are not limited thereto.

In the case where the first dicarbonyl compound and the second dicarbonyl compound are each aromatic dicarbonyl compounds, since they contain a benzene ring, mechanical properties such as the surface hardness and the tensile strength of the polyamide-imide film prepared Can contribute to the improvement.

The dicarbonyl compound may include terephthaloyl chloride (TPC), 4,4'-oxybisbenzoyl chloride (DEDC) having a structure as follows, or a combination thereof. However, the present invention is not limited thereto.

For example, the first dicarbonyl compound may include DEDC, and the second dicarbonyl compound may include TPC, but is not limited thereto.

Specifically, when using DEDC as the first dicarbonyl compound and TPC as the second dicarbonyl compound in a suitable combination, the polyamide-imide film prepared may have high oxidation resistance.

The diamine compound and the dicarbonyl compound may be polymerized to form a repeating unit represented by the following Formula B.

<Formula B>

In the general formula (B), description of E, J, e, and j is as described above.

For example, the diamine compound and the dicarbonyl compound may be polymerized to form an amide repeating unit represented by Formulas B-1 and B-2.

<Formula B-1>

X in Chemical Formula B-1 is an integer of 1 to 400.

<Formula B-2>

Y in Formula B-2 is an integer of 1 to 400.

Polyamide-imide film according to another embodiment comprises a polyamide-imide polymer formed by polymerizing an aromatic diamine compound, an aromatic dianhydride compound and a dicarbonyl compound, wherein the aromatic diamine compound is one A diamine compound is included, and the aromatic dianhydride compound includes one aromatic dianhydride compound, and the dicarbonyl compound may include two dicarbonyl compounds.

Alternatively, the aromatic diamine compound consists of one kind of diamine compound, the aromatic dianhydride compound consists of one kind of aromatic dianhydride compound, and the dicarbonyl compound consists of two kinds of dicarbonyl compound. Can be.

For example, the diamine compound may be 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl (2,2'-Bis (trifluoromethyl) -4,4'-diaminodiphenyl, TFDB) Wherein, the dianhydride compound is 2,2'-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride (2,2'-Bis (3,4-Dicarboxyphenyl) hexafluoropropane dianhydride, 6 -FDA), and the dicarbonyl compound may include terephthaloyl chloride (TPC), 4,4'-oxybisbenzoyl chloride (DEDC), or a combination thereof. It may be, but is not limited thereto.

Alternatively, the diamine compound may be composed of 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl (2,2'-Bis (trifluoromethyl) -4,4'-diaminodiphenyl, TFDB). The dianhydride compound is 2,2'-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride (2,2'-Bis (3,4-Dicarboxyphenyl) hexafluoropropane dianhydride, 6-FDA The dicarbonyl compound may be composed of terephthaloyl chloride (TPC) and 4,4'-oxybisbenzoyl chloride (DEDC), but is not limited thereto. It is not.

One embodiment is characterized in that by appropriately adjusting the content of the imide repeating unit and the amide repeating unit, it is possible to obtain a polyamide-imide film in which the optical properties, mechanical properties and flexibility are improved in balance without complicated procedures.

In addition, it is possible to obtain a polyamide-imide film in which optical properties, mechanical properties, and flexibility are improved in balance without undergoing precipitation, filtration and drying, re-dissolution, and the like.

The content of each of the imide repeating unit and the amide repeating unit may be controlled by the amount of the aromatic dianhydride compound and the dicarbonyl compound.

The polyamide-imide film satisfies the following general formula 1:

<Formula 1>

4 ≤ X / Y ≤ 12

X: Maximum diameter in milling, including cracks, when the film was punched at a speed of 10 mm / min using a 2.5 mm spherical tip in UTM compression mode.

Y: modulus of the film (GPa)

The polyamide-imide film has a maximum aperture diameter (X) of 60 mm or less based on 50 μm. Specifically, the maximum diameter of the perforations may be 5 to 60 mm, 10 to 60 mm, 15 to 60 mm, 20 to 60 mm, 25 to 60 mm, or 25 to 58 mm, but is not limited thereto.

The polyamide-imide film has a compressive strength of 0.4 kgf / μm or more based on 50 μm in thickness. Specifically, the compressive strength may be 0.45 kgf / μm or more or 0.46 kgf / μm or more, but is not limited thereto.

The polyamide-imide film has a surface hardness of HB or higher. Specifically, the surface hardness may be H or more or 2H or more, but is not limited thereto.

The polyamide-imide film has a light transmittance of 85% or more, measured at 550 nm, based on a thickness of 50 μm. Specifically, the light transmittance may be 86% or more, 87% or more, or 88% or more, 89% or more, 90% or more, or 90.5% or more, but is not limited thereto.

The polyamide-imide film has a haze of 2% or less based on a thickness of 50 μm. Specifically, the haze may be 1.8% or less, 1.5% or less, 1.2% or less, 1.0% or less, 0.8% or less, 0.7% or less, 0.6% or less, 0.5% or less, 0.4% or less, 0.35% or less, or 0.34% or less. However, the present invention is not limited thereto.

The polyamide-imide film has a yellowness of 5 or less based on a thickness of 50 μm. Specifically, the yellowness may be 3 or less, 2 or less, 1.7 or less, 1.5 or less, or 1.4 or less, but is not limited thereto.

The polyamide-imide film has a modulus of 5.0 GPa or more based on a thickness of 50 μm. Specifically, the modulus may be 5.5 GPa or more, 5.8 GPa or more, 6.0 GPa or more, 6.2 GPa or more, or 6.4 GPa or more, but is not limited thereto.

The polyamide-imide film has a tensile strength of 10 kgf / mm ² or more based on 50 μm. Specifically, the tensile strength may be 11 kgf / mm ² or more or 11.5 kgf / mm ^{2 or} more, but is not limited thereto.

The polyamide-imide film has an elongation of 15% or more based on a thickness of 50 μm. Specifically, the elongation may be 17% or more, 18% or more, 20% or more, 23% or more, or 25% or more, but is not limited thereto.

Various properties can be combined for the polyamide-imide film described above.

[ Polyamide -Method of producing imide film]

The embodiment provides a method for producing a film having high elongation and also excellent optical and mechanical properties.

Method for producing a polyamide-imide film according to an embodiment, preparing a polyamide-imide polymer solution comprising a repeating unit represented by the following formula A and a repeating unit represented by the formula (B); Introducing the polymer solution into a tank; Extruding and casting the polymer solution in the tank and drying to prepare a gel sheet; And heat treating the gel sheet.

<Formula A>

<Formula B>

In Formulas A and B,

E and J are, independently from each other, a substituted or unsubstituted divalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted divalent C ₆ -C ₃₀ aromatic ring group, substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaromatic ring group, substituted or unsubstituted C ₁ -C ₃₀ alkylene group, substituted or unsubstituted C ₂ -C ₃₀ alkenylene group , Substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-, -S-, -C (= O)-, -CH (OH)-, -S (= O) _2- , -Si ( CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) _2- ,

e and j are each independently selected from an integer of 1 to 5,

when e is 2 or more, two or more E are the same as or different from each other,

when j is 2 or more, two or more J are the same as or different from each other,

G is a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aromatic ring group , A substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaromatic ring group, wherein the aliphatic ring group, the heteroaliphatic ring group, the aromatic ring group or the heteroaromatic ring group are present alone, or are bonded to each other to form a condensed ring Form a substituted or unsubstituted C ₁ -C ₃₀ alkylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkenylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-,- S-, -C (= 0)-, -CH (OH)-, -S (= 0) _2- , -Si (CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) ₂ -are connected by the connector selected from

The repeating unit represented by the formula (B) includes two or more different repeating units,

At least one of the two or more repeating units includes a group in which (J) _j comprises -O-,

At least one of the two or more repeating units includes a group in which (J) _j does not contain -O-.

At this time, the description of the repeating unit represented by the formula (A), the repeating unit represented by the formula (B), the polyamide-imide polymer, the polyamide-imide film and the like is as described above.

In the method for producing a polyamide-imide film according to an embodiment, first, a polyamide-imide polymer solution including a repeating unit represented by Formula A and a repeating unit represented by Formula B is prepared.

In this case, the molar ratio of the repeating unit represented by Formula A and the repeating unit represented by Formula B may be 20:80 to 80:20. Specifically, the molar ratio of the repeating unit represented by Formula A and the repeating unit represented by Formula B is 30:70 to 80:20, 40:60 to 80:20, 50:50 to 80:20, 50:50 To 70:30, 55:45 to 70:30, or 55:45 to 65:35, and more specifically, to 60:40, but is not limited thereto.

Specifically, preparing the polyamide-imide polymer solution is a step of preparing a polyamide-imide polymer solution by polymerizing a diamine compound, a dianhydride compound and a dicarbonyl compound on an organic solvent.

The description of the diamine compound, the dianhydride compound and the dicarbonyl compound is as described above.

Specifically, the diamine compound is represented by the following Chemical Formula 1, the dianhydride compound is represented by the following Chemical Formula 2, and the dicarbonyl compound is represented by the following Chemical Formula 3:

<Formula 1>

<Formula 2>

<Formula 3>

In Formulas 1 to 3,

Description of E, G, J, e, j and X is as described above,

The dicarbonyl compound comprises two different dicarbonyl compounds,

One dicarbonyl compound includes a group in which (J) _j comprises -O-,

One dicarbonyl compound includes a group in which (J) _j does not contain -O-.

In addition, the diamine compound may be made of a compound having a fluorine-containing substituent, and the dianhydride compound may be made of a compound having a fluorine-containing substituent, but is not limited thereto.

In addition, the dicarbonyl compound may include a first dicarbonyl compound and a second dicarbonyl compound. In this case, the preparing of the polymer solution may include obtaining a first polymer solution by polymerizing a diamine compound, a dianhydride compound, a first dicarbonyl compound, and a second dicarbonyl compound in an organic solvent; And further adding the second dicarbonyl compound to the first polymer solution to obtain a second polymer solution. However, the present invention is not limited thereto.

The polymer solution comprises a polyamide-imide polymer and an organic solvent.

The organic solvent is dimethylformamide (DMF), dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), m-cresol ), Tetrahydrofuran (THF) and one or more selected from the group consisting of chloroform, but is not limited thereto. Specifically, the organic solvent may be dimethylacetamide (DMAc), but is not limited thereto.

In the obtaining of the first polymer solution, the diamine compound, the dianhydride compound, the first dicarbonyl compound, and the second dicarbonyl compound may be simultaneously or sequentially polymerized.

Specifically, according to one embodiment, the step of obtaining the first polymer solution, the diamine compound, the dianhydride compound, the first dicarbonyl compound and the second dicarbonyl compound may be simultaneously polymerized. .

According to another embodiment, the obtaining of the first polymer solution may include: polymerizing the diamine compound and the dianhydride compound to obtain a polyamic acid solution; And polymerizing by adding the first dicarbonyl compound and the second dicarbonyl compound to the polyamic acid solution. The polyamic acid solution is a solution containing polyamic acid.

According to another embodiment, the obtaining of the first polymer solution may include: polymerizing the diamine compound and the dianhydride compound to obtain a polyamic acid solution; Dehydrating the polyamic acid solution to obtain a polyimide solution; And polymerizing by adding the first dicarbonyl compound and the second dicarbonyl compound to the polyimide solution. The polyimide solution is a solution containing a polymer having an imide repeat unit.

According to another embodiment, the obtaining of the first polymer solution may include: polymerizing the diamine compound, the first dicarbonyl compound, and the second dicarbonyl compound to obtain an amide polymer solution; And polymerizing by adding the dianhydride compound to the amide polymer solution. The amide polymer solution is a solution comprising a polymer having an amide repeat unit.

The copolymer contained in the first polymer solution is an imide repeating unit derived from the polymerization of the diamine compound and the dianhydride compound, and an amide derived from the polymerization of the diamine compound and the dicarbonyl compound ( amide) repeating units. The? Imide repeating unit may be a repeating unit represented by Formula A, and the amide repeating unit may be a repeating unit represented by Formula B.

After obtaining the first polymer solution, obtaining the second polymer solution, or preparing the polyamide-imide polymer solution, a catalyst may be further added.

Examples of the catalyst include, but are not limited to, beta picoline or acetic anhydride.

By further adding the catalyst, the reaction rate can be increased, and there is an effect of improving the bonding force between the repeating unit structures or in the repeating unit structure.

In addition, in the process of adding the catalyst, drying and re-dissolving the polymer solution or adding a solvent, the viscosity of the polymer solution may be appropriately adjusted to be suitable for the extrusion process.

Another embodiment includes the step of obtaining the first polymer solution, the dianhydride compound, the first dicarbonyl compound and the second dicarbonyl compound in an excess of the diamine compound.

Specifically, based on the total moles of the dianhydride compound, the first dicarbonyl compound and the second dicarbonyl compound, the dianhydride compound may be included in 20 mol% to 80 mol%, It is not limited to this.

When the content of the dianhydride compound is within the above range, the mechanical properties such as modulus, tensile strength, elongation and surface hardness of the polyamide-imide film are excellent.

Further, based on the total moles of the dianhydride compound, the first dicarbonyl compound, and the second dicarbonyl compound, the first dicarbonyl compound and the second dicarbonyl compound may be 20 mol% to 20 mol%. 80 mol% may be included, but is not limited thereto.

 When the content of the dicarbonyl compound is within the above range, the optical properties such as light transmittance and haze of the polyamide-imide film are excellent.

In yet another embodiment, the step of obtaining a first polymer solution, based on the total moles of the first dicarbonyl compound and the second dicarbonyl compound, 20 to 80% of the first dicarbonyl compound It may include in mol%, but is not limited thereto.

The first dicarbonyl compound may be 4,4'-oxybisbenzoyl chloride (DEDC), and the second dicarbonyl compound may be terephthaloyl chloride (TPC). have.

When the content of the first dicarbonyl compound is within the above range, it is possible to realize a film having high elongation without impairing optical properties of the film, and since the film has excellent flexibility, it is useful in the field of flexible displays. Can be used.

Preferably, in the step of obtaining the first polymer solution, i) an excess of diamine compound that is at least the same mole as the remaining reactant, ii) the dianhydride compound, the first dicarbonyl compound and the second 20 mole% to 80 mole% of dianhydride compound based on the total moles of dicarbonyl compound, and iii) the total of the dianhydride compound, the first dicarbonyl compound and the second dicarbonyl compound. It may be prepared using 20 mol% to 80 mol% of the first dicarbonyl compound and the second dicarbonyl compound on a molar basis.

Specifically, 20 mol% to 80 mol% of the first dicarbonyl compound (4,4′-oxybisbenzoyl chloride) based on the total moles of the first dicarbonyl compound and the second dicarbonyl compound. (4,4'-oxybisbenzoyl chloride, DEDC)) and 80 mol% to 20 mol% of the second dicarbonyl compound (terephthaloyl chloride (TPC)).

In the step of obtaining the first polymer solution, by appropriately adjusting the content of each imide repeat unit and amide repeat unit, optical properties, mechanical properties and flexibility without going through the process of precipitation, filtration and drying, re-dissolution, etc. as in the prior art This balanced improved polyamide-imide film can be obtained.

After obtaining the first polymer solution, the second polymer solution may be further added to the first polymer solution to obtain a second polymer solution having a viscosity of 100,000 to 300,000 cps. Specifically, a second polymer solution having a viscosity of 100,000 to 250,000 cps, 150,000 to 250,000 cps, and 150,000 to 300,000 cps can be obtained.

When the viscosity of the second polymer solution is in the above range, the polyamide-imide film may be effectively produced in the extrusion and casting process. In addition, the produced polyamide-imide film may have mechanical properties such as improved modulus.

The weight ratio of the second dicarbonyl compound added in the step of obtaining the first polymer solution and the second dicarbonyl compound added in the step of obtaining the second polymer solution may be 90:10 to 99: 1, but It is not limited.

In addition, the second dicarbonyl compound added in the step of obtaining the second polymer solution may be used as a second dicarbonyl compound solution prepared by mixing with an organic solvent at a concentration of 5 to 20% by weight, but is not limited thereto. no.

This is advantageous in that the desired viscosity can be achieved accurately.

According to one embodiment, the content of solids contained in the second polymer solution may be 10% to 20% by weight. Specifically, the content of solids included in the second polymer solution may be 12 wt% to 18 wt%, but is not limited thereto.

When the content of the solid content contained in the second polymer solution is within the above range, the polyamide-imide film may be effectively produced in the extrusion and casting process. In addition, the produced polyamide-imide film may have mechanical properties such as improved modulus and optical properties such as low yellowness.

After obtaining the second polymer solution, the pH of the second polymer solution can be adjusted by adding a neutralizing agent.

Examples of the neutralizer include, but are not limited to, amine-based neutralizers such as alkoxyamines, alkylamines or alkanolamines.

The neutralizing agent may be added in an amount of about 0.1 mol% to about 10 mol% based on the total moles of monomers in the polyamide-imide polymer solution.

The pH of the second polymer solution adjusted through the neutralizer may be about 4 to about 7. Specifically, the pH of the adjusted second polymer solution may be about 4.5 to about 7.

When the pH of the second polymer solution is in the above range, it is possible to prevent damage to equipment generated in the extrusion and casting process described later. In addition, it may have an effect in terms of mechanical properties, such as improving the optical properties and modulus, such as lowering the yellowness of the polyamide-imide film to be produced or to prevent the increase in yellowness.

After preparing the polymer solution, the polymer solution is added to a tank.

At this time, the internal temperature of the tank is preferably -20 to 20 ℃. This is to prevent deterioration of the polymer solution to be added and to lower the moisture content.

After the step of introducing the prepared polymer solution into the tank, vacuum degassing for 30 minutes to 3 hours until the pressure in the tank is 0.1 to 0.7 bar; may further comprise a.

Alternatively, after the step of introducing the prepared polymer solution into the tank, purging the tank to 1 to 2 atm using nitrogen gas; may further include a.

The vacuum defoaming and purging the tank with nitrogen gas are performed in a separate process.

For example, the step of vacuum degassing may be performed, and thereafter, the step of purging the tank with nitrogen gas may be performed, but is not limited thereto.

By performing the step of vacuum degassing and / or purging the tank with nitrogen gas, physical properties of the prepared polyamide-imide film surface may be improved.

Subsequently, the polymer solution in the tank is extruded and cast and then dried to prepare a gel sheet.

In the extrusion and casting process, the above-mentioned organic solvent may be used.

The polymer solution is extruded and cast into a casting sieve, such as a casting roll or casting belt. It can then be cast to the casting sieve at a rate of about 0.5 m / min to about 15 m / min and also at a thickness of 200 to 700 μm. When the extrusion and casting speed is within the above range, the polyamide-imide film produced by the manufacturing method according to the embodiment may have improved optical and mechanical properties.

That is, when the polymer solution has the above viscosity, it may be advantageous to have the improved optical and mechanical properties to be extruded and cast at the same extrusion rate.

After the polymer solution is cast into the casting sieve, a gel sheet is formed on the casting sieve by removing the solvent contained in the polymer solution by a drying process.

The drying process may be performed at a temperature of about 60 ° C. to about 150 ° C., for a time of about 5 minutes to about 60 minutes.

Subsequently, a polyamide-imide film according to the embodiment may be prepared by subjecting the gel sheet to heat treatment.

The heat treatment step may be performed for 5 to 40 minutes or 5 to 30 minutes while increasing the temperature at a rate of 2 ℃ / min to 80 ℃ / min in the temperature range of 80 to 500 ℃, specifically 30 to 300 ℃.

The maximum temperature during the heat treatment step may be 300 to 500 ℃, 200 to 300 ℃, 250 to 300 ℃ or 320 to 500 ℃. More specifically, the maximum temperature during the heat treatment step may be 270 to 300 ℃, 350 to 500 ℃, 380 to 500 ℃, 400 to 500 ℃, 410 to 480 ℃, 410 to 470 ℃ or 410 to 450 ℃, but is not limited thereto. It is not.

After the heat treatment step, the step of reducing the heat treated sheet; may further include. The step of temperature reduction may include a first temperature reduction step of reducing the temperature at a rate of 100 ° C./min to 1000 ° C./min and a second temperature reduction step of reducing the temperature at a rate of 40 ° C./min to 400 ° C./min.

Specifically, a second temperature reduction step is performed after the first temperature reduction step.

In addition, the temperature reduction rate of the first temperature reduction step may be faster than the temperature reduction rate of the second temperature reduction step.

For example, the maximum speed of the first temperature reduction step is faster than the maximum speed of the second temperature reduction step. Alternatively, the lowest speed of the first temperature reduction step is faster than the lowest speed of the second temperature reduction step.

Since the polyamide-imide polymer has high oxidation resistance, it is hardly affected by oxygen contained in the atmosphere during the heat treatment process. Thus, the polyamide-imide film according to the embodiment may have improved mechanical and optical properties.

In addition, conventionally, in manufacturing a polyimide film, yellowing of the film is prevented and transparency is ensured through purging nitrogen gas during the heat treatment of the film forming process, but according to the embodiment, polyamide having excellent optical characteristics without purging nitrogen gas -Imide films can be obtained.

For description of the polyamide-imide film produced by the method for producing the polyamide-imide film, refer to the description described in the above [Polyamide-imide film].

[ Example ]

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto.

Example  One

A double-jacketed 1 L glass reactor was charged with 667.7 g of organic solvent dimethylacetamide (DMAc) under nitrogen atmosphere at 20 ° C., and then aromatic diamine 2,2′-bis (trifluoromethyl) -4 64 g (0.2 mol) of 4'-diaminobiphenyl (TFDB) was slowly added thereto and dissolved.

Subsequently, 53.3 g (0.12 mol) of 2,2'-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6-FDA), which is an aromatic dianhydride, was stirred for 1 hour while being slowly added thereto.

11.8 g (0.04 mol) of 4,4'-oxybiszenzoyl chloride (DEDC) was added as the first dicarbonyl compound, followed by stirring for 1 hour, and terephthaloyl chloride (TPC) as the second dicarbonyl compound. ) Was added 6.5 g (0.032 mol) which is 96% of the added mole, and stirred for 1 hour to prepare a first polymer solution.

If the viscosity of the prepared first polymer solution was measured and then the measured viscosity did not reach the desired viscosity, a 10 wt% TPC solution was added to the DMAc organic solvent and 1 mL was added until the viscosity reached 200,000 cps. After the stirring was repeated for 30 minutes, a second polymer solution was prepared.

Subsequently, after apply | coating the said 2nd polymer solution to the glass plate, it dried for 30 minutes by 80 degreeC hot air. After peeling the dried polyamide-imide polymer from the glass plate, and fixed to the pin frame and heat-treated for 30 minutes at a rate of 2 ℃ / min to 80 ℃ / min in the temperature range of 80 ℃ to 300 ℃ to a thickness of 50 ㎛ A polyamide-imide film was obtained.

According to the above embodiment, the yield reaches about 100% immediately before the film forming step (just before application). In the present specification, 'yield' refers to a mole of material remaining in a solution for application compared to a mole of injected material. Means.

According to the conventional manufacturing method, the yield just before the film forming step is about 60%, since the loss of material inevitably occurs at the stage of polyimidization reaction, precipitation, filtration and drying.

Example  2, 3 and Comparative example  1 to 3

A polyamide-imide film was prepared in the same manner as in Example 1 except that the diamine compound, dianhydride compound, and dicarbonyl compound were added in the amounts shown in Table 1 below.

Table 1 shows the moles and weights of each of the diamine compound, dianhydride compound, and dicarbonyl compound, and the lower portion thereof describes the weight ratio of the dianhydride compound and the dicarbonyl compound based on 100 parts by weight of the diamine compound. In addition, A: B shows the molar ratio of imide repeating unit: amide repeating unit.

[ Evaluation example ]

The physical properties of the films according to Examples 1 to 3 and Comparative Examples 1 to 3 were measured and evaluated as follows. The results are shown in Table 2 below.

Evaluation example  1: thickness measurement of film

Using a digital micrometer 547-401 manufactured by Mitsutoyo Corp., Japan, the thickness was measured with an average value by measuring 5 points in the width direction.

Evaluation example  2 : Light transmittance  And Haze  Measure

The light transmittance and haze at 550 nm were measured using the haze meter NDH-5000W of Denshoku Kogyo Co., Ltd., Japan.

Evaluation example  3: yellowness measurement

Yellowness index (YI) was measured using a CIE colorimeter by a spectrophotometer (UltraScan PRO, Hunter Associates Laboratory).

Evaluation example  4: tensile strength and elongation measurement

Using Instron's universal testing machine UTM 4206-001, cut at least 5 cm in the direction orthogonal to the main shrinkage direction of the sample and 15 mm in the main shrinkage direction, and attach it to clips at 5 cm intervals and then break at room temperature. A stress-strain curve was obtained until this occurred. The force applied when the fracture occurred was the tensile strength (kgf / mm ² ), and the increased ratio was the elongation (%).

As can be seen from Table 2, in Examples 1 to 3, as compared with Comparative Examples 1 to 3, the overall high light transmittance, low haze, low yellowness, and high tensile strength, while maintaining the overall tensile strength In this case, the improvement was remarkable.

Claims (23)

A polyamide-imide film comprising a repeating unit represented by the following Formula A and a repeating unit represented by the following Formula B:
<Formula A>

<Formula B>

In Formulas A and B,
E and J are, independently from each other, a substituted or unsubstituted divalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted divalent C ₆ -C ₃₀ aromatic ring group, substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaromatic ring group, substituted or unsubstituted C ₁ -C ₃₀ alkylene group, substituted or unsubstituted C ₂ -C ₃₀ alkenylene group , Substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-, -S-, -C (= O)-, -CH (OH)-, -S (= O) _2- , -Si ( CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) _2- ,
e and j are each independently selected from an integer of 1 to 5,
when e is 2 or more, two or more E are the same as or different from each other,
when j is 2 or more, two or more J are the same as or different from each other,
G is a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aromatic ring group , A substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaromatic ring group, wherein the aliphatic ring group, the heteroaliphatic ring group, the aromatic ring group or the heteroaromatic ring group are present alone, or are bonded to each other to form a condensed ring Form a substituted or unsubstituted C ₁ -C ₃₀ alkylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkenylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-,- S-, -C (= 0)-, -CH (OH)-, -S (= 0) _2- , -Si (CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) ₂ -are connected by the connector selected from
The repeating unit represented by the formula (B) includes two or more different repeating units,
At least one of the two or more repeating units includes a group in which (J) _j comprises -O-,
At least one of the two or more repeating units includes a group in which (J) _j does not contain -O-.
The method of claim 1,
(E) _e is a polyamide-imide film selected from the group represented by the following formula 1-1a to 1-14a:

The method of claim 1,
(E) _e is a polyamide-imide film selected from the group represented by the following formula 1-1b to 1-13b:

The method of claim 1,
G is a polyamide-imide film selected from the group represented by the following Chemical Formulas 2-1a to 2-9a:

The method of claim 1,
(J) _j is a group represented by the following Chemical Formula 3-10a; And a group selected from the groups represented by Formulas 3-1a to 3-9a and 3-11a to 3-14a.

The method of claim 1,
(J) _j is a group represented by the following Chemical Formula 3-4b or 3-5b; And a group selected from the groups represented by Formulas 3-1b to 3-3b and 3-6b to 3-8b.

The method of claim 1,
(E) Polyamide-imide film whose 1 or more types of _e and G are fluorine-containing groups.
The method of claim 1,
(E) The polyamide-imide film, wherein both _e and G are fluorine-containing groups.
The method of claim 1,
A polyamide-imide film, wherein the molar ratio of the repeating unit represented by Formula A and the repeating unit represented by Formula B is 20:80 to 80:20.
The method of claim 1,
A polyamide-imide film having an elongation of 15% or more based on a thickness of 50 μm of the polyamide-imide film.
Preparing a polyamide-imide polymer solution comprising a repeating unit represented by the following Formula A and a repeating unit represented by the following Formula B;
Introducing the polymer solution into a tank;
Extruding and casting the polymer solution in the tank and drying to prepare a gel sheet; And
Comprising: heat treating the gel sheet;
Process for preparing polyamide-imide film:
<Formula A>

<Formula B>

In Formulas A and B,
E and J are, independently from each other, a substituted or unsubstituted divalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted divalent C ₆ -C ₃₀ aromatic ring group, substituted or unsubstituted divalent C ₄ -C ₃₀ heteroaromatic ring group, substituted or unsubstituted C ₁ -C ₃₀ alkylene group, substituted or unsubstituted C ₂ -C ₃₀ alkenylene group , Substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-, -S-, -C (= O)-, -CH (OH)-, -S (= O) _2- , -Si ( CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) _2- ,
e and j are each independently selected from an integer of 1 to 5,
when e is 2 or more, two or more E are the same as or different from each other,
when j is 2 or more, two or more J are the same as or different from each other,
G is a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aliphatic ring group, a substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaliphatic ring group, a substituted or unsubstituted tetravalent C ₆ -C ₃₀ aromatic ring group , A substituted or unsubstituted tetravalent C ₄ -C ₃₀ heteroaromatic ring group, wherein the aliphatic ring group, the heteroaliphatic ring group, the aromatic ring group or the heteroaromatic ring group are present alone, or are bonded to each other to form a condensed ring Form a substituted or unsubstituted C ₁ -C ₃₀ alkylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkenylene group, a substituted or unsubstituted C ₂ -C ₃₀ alkynylene group, -O-,- S-, -C (= 0)-, -CH (OH)-, -S (= 0) _2- , -Si (CH ₃ ) _2- , -C (CH ₃ ) ₂ -and -C (CF ₃ ) ₂ -are connected by the connector selected from
The repeating unit represented by the formula (B) includes two or more different repeating units,
At least one of the two or more repeating units includes a group in which (J) _j comprises -O-,
At least one of the two or more repeating units includes a group in which (J) _j does not contain -O-.
The method of claim 11,
Preparing the polyamide-imide polymer solution
Polymerizing a diamine compound, a dianhydride compound and a dicarbonyl compound on an organic solvent to prepare a polyamide-imide polymer solution.
Method for producing a polyamide-imide film.
The method of claim 12,
The diamine compound is represented by the following formula (1),
The dianhydride compound is represented by the following formula (2),
The dicarbonyl compound is represented by the following formula (3), a method for producing a polyamide-imide film:
<Formula 1>

<Formula 2>

<Formula 3>

In Formulas 1 to 3,
Description of E, G, J, e and j is as described in claim 11,
X is a halogen atom,
The dicarbonyl compound comprises two different dicarbonyl compounds,
One dicarbonyl compound includes a group in which (J) _j comprises -O-,
One dicarbonyl compound includes a group in which (J) _j does not contain -O-.
The method of claim 12,
The diamine compound consists of a compound having a fluorine-containing substituent,
The said dianhydride compound consists of a compound which has a fluorine-containing substituent, The manufacturing method of the polyamide-imide film.
The method of claim 11,
The molar ratio of the repeating unit represented by the said Formula A and the repeating unit represented by the said Formula B is 20: 80-80: 20, The manufacturing method of the polyamide-imide film.
The method of claim 11,
Based on the thickness of the polyamide-imide film 50 ㎛, elongation of 15% or more, a method for producing a polyamide-imide film.
The method of claim 11,
The viscosity of the polymer solution is 100,000 to 300,000 cps,
Method for producing a polyamide-imide film.
The method of claim 11,
The internal temperature of the tank is -20 to 20 ℃,
Method for producing a polyamide-imide film.
The method of claim 11,
After the step of introducing the polymer solution into the tank,
Vacuum degassing for 30 minutes to 3 hours until the pressure in the tank is 0.1 to 0.7 bar, further comprising,
Method for producing a polyamide-imide film.
The method of claim 11,
After the step of introducing the polymer solution into the tank,
Purging the tank at 1 to 2 atmospheres using nitrogen gas; further comprising:
Method for producing a polyamide-imide film.
The method of claim 11,
The drying is carried out at a temperature of 60 ℃ to 150 ℃, for a time of 5 minutes to 60 minutes,
Method for producing a polyamide-imide film.
The method of claim 11,
The heat treatment step is performed for 5 to 40 minutes while increasing the temperature at a rate of 2 ℃ / min to 80 ℃ / min in the temperature range of 80 to 500 ℃, the maximum temperature of the heat treatment step is 300 to 500 ℃,
Method for producing a polyamide-imide film.
The method of claim 11,
After the heat treatment step,
Depressing the heat treated sheet; further comprising,
The temperature reduction step includes a first temperature reduction step of reducing the temperature at a rate of 100 ° C./min to 1000 ° C./min and a second temperature reduction step of reducing the temperature at a rate of 40 ° C./min to 400 ° C./min.
A second temperature reduction step is performed after the first temperature reduction step,
The temperature reduction rate of the said first temperature reduction step is faster than the temperature reduction rate of the said second temperature reduction step, The manufacturing method of the polyamide-imide film.