TW202409147A - Polyamic acid composition, polyimide production method, laminate production method, and electronic device production method - Google Patents

Abstract

This polyamic acid composition contains a polyamic acid and an organic solvent. The polyamic acid has a residue including a divalent organic group represented by chemical formula (1), a 3,3',4,4'-biphenyl tetracarboxylic dianhydride residue, and a p-phenylene diamine residue. The organic solvent contains at least one compound selected from the group consisting of compounds represented by general formula (2) and compounds represented by general formula (3). In general formula (2), R1, R2, and R3 each independently represent a hydrogen atom or a monovalent organic group having one or more carbon atoms, and at least one of R1, R2, and R3 represents a monovalent organic group having two or more carbon atoms. In general formula (3), R4 represents a monovalent organic group having two or more carbon atoms.

Description

Polyamic acid composition, method for producing polyimide, method for producing laminate, and method for producing electronic device

The present invention relates to a polyamide composition, a method for producing polyimide, a method for producing a laminate, and a method for producing an electronic device. The present invention further relates to an electronic device material using polyimide, a thin film transistor (TFT) substrate, a flexible display substrate, a color filter, a printed matter, an optical material, an image display device (more specifically, a liquid crystal display device, an organic EL (Electroluminescence), an electronic paper, etc.), a 3D display, a solar cell, a touch panel, a transparent conductive film substrate, and a substitute material for components currently using glass.

With the rapid development of displays such as liquid crystal displays, organic EL, electronic paper, or electronic devices such as solar cells and touch panels, the thinning, lightening, and flexibility of devices are constantly progressing. In these devices, polyimide is used as a substrate material instead of a glass substrate.

In these devices, various electronic components, such as thin film transistors or transparent electrodes, are formed on the substrate, and the formation of these electronic components requires a high temperature process. Polyimide has sufficient heat resistance to adapt to the high temperature process, and its coefficient of thermal expansion (CTE) is close to that of glass substrates or electronic components. Therefore, it is not easy to generate internal stress and is suitable for use as a substrate material for flexible displays.

The substrate material described above can be manufactured by applying a solution containing polyamide (polyamide composition) onto a support, imidizing the polyamide to form a polyimide film, and then stacking electronic components thereon.

As solvents for dissolving polyamine, amide-based solvents with relatively small carbon atoms such as N,N-dimethylformamide (DMF), N-methyl-2-pyrrolidone (NMP), and N,N-dimethylacetamide (DMAC) are generally used. From the perspective of the impact on the environment or the human body, there is a gradual demand for a change to a safer solvent.

As an example of preparing a polyamine composition using a safer solvent, there is a known example of using water as a solvent by using a polyamine salt (Patent Document 1, etc.). In addition, there is a known example of synthesizing polyamine using alkoxy-N-substituted propionamide as a solvent with lower teratogenicity concerns (Patent Documents 2 and 3, etc.). [Prior Art Documents] [Patent Documents]

[Patent Document 1] Japanese Patent Application Publication No. 2012-36382 [Patent Document 2] Japanese Patent Publication No. 2017-517582 [Patent Document 3] International Publication No. 2022/054850

[The problem the invention is trying to solve]

The inventors of the present invention have conducted verification and found that if the polyamide composition described in patent documents 1 to 3 is coated on a support and the polyamide is imidized, poor adhesion is likely to occur between the obtained polyimide film and the support, and the internal stress generated at the interface between the polyimide film and the support tends to increase. Hereinafter, the poor adhesion between the polyimide film and the support is sometimes referred to as "poor adhesion". In addition, the internal stress generated at the interface between the polyimide film and the support is sometimes referred to as "internal stress". If the internal stress increases, there is a possibility that it is difficult to apply to electronic devices.

The present invention was completed in view of the above-mentioned actual situation, and its object is to provide a polyamide composition that can not only use a highly safe solvent and suppress the occurrence of poor adhesion but also reduce internal stress, and use the polyamide composition using the polyamide composition. A method for manufacturing polyimide of an amino acid composition, a method for manufacturing a laminated body, and a method for manufacturing an electronic device. [Technical means to solve problems]

<Aspects of the present invention> The present invention includes the following aspects.

[1] A polyamide composition containing polyamide and an organic solvent, and The above-mentioned polyamide has a residue containing a divalent organic group represented by the following chemical formula (1), a 3,3',4,4'-biphenyltetracarboxylic dianhydride residue, and a p-phenylenediamine residue. base, The organic solvent includes one or more compounds selected from the group consisting of a compound represented by the following general formula (2) and a compound represented by the following general formula (3).

[Chemistry 1]

In the above general formula (2), ^R1 , ^R2 and ^R3 each independently represent a hydrogen atom or a monovalent organic group having 1 or more carbon atoms, and at least one of ^R1 , ^R2 and ^R3 represents a monovalent organic group having 2 or more carbon atoms. In the above general formula (3), ^R4 represents a monovalent organic group having 2 or more carbon atoms.

[2] The polyamino acid composition described in [1] above, wherein the residue of the divalent organic group represented by the chemical formula (1) is selected from one or more residues of the group consisting of a tetravalent organic group represented by the chemical formula (4), a tetravalent organic group represented by the chemical formula (5), and a divalent organic group represented by the chemical formula (6).

[Chemicalization 2]

[3] The polyamic acid composition according to the above [1] or [2], wherein the content rate of the residues containing the divalent organic group represented by the above chemical formula (1) is relative to the ratio of the residues constituting the above-mentioned polyamic acid. The total 100 mol% of all the tetracarboxylic dianhydride residues and all the diamine residues constituting the above-mentioned polyamide acid is 15 mol% or less.

[4] The polyamine composition as described in any one of [1] to [3] above, wherein the organic solvent is 3-methoxy-N,N-dimethylpropionamide, 3-butoxy-N,N-dimethylpropionamide or 1-butyl-2-pyrrolidone.

[5] The polyamic acid composition according to any one of the above [1] to [4], wherein the polyamic acid further has 1,3-bis(3-aminopropyl)tetramethyl Disiloxane residue.

[6] The polyamide composition according to the above [5], wherein the content of the 1,3-bis(3-aminopropyl)tetramethyldisiloxane residue is The total amount of diamine residues of amide acid is 0.1 mol% or more and 1.0 mol% or less.

[7] The polyamide composition as described in any one of [1] to [6] above, further comprising a silane coupling agent.

[8] A method for producing polyimide, comprising heating the polyimide composition as described in any one of [1] to [7] above to imidize the polyimide.

[9] A method for manufacturing a laminated body, the laminated body having a support and a polyimide film, and The above method is to form a coating film containing the above-mentioned polyamic acid by coating the polyamic acid composition as described in any one of the above-mentioned [1] to [7] on a support, and then The above-mentioned coating film is heated to imidize the above-mentioned polyamide acid.

[10] A method for manufacturing an electronic device, comprising: Step Sa, which is to heat the polyimide composition described in any one of [1] to [7] above to imidize the polyimide; and Step Sb, which is to arrange an electronic element on the polyimide film obtained by the above step Sa. [Effect of the invention]

According to the present invention, a polyamic acid composition can be provided which can not only use a safer solvent and suppress the occurrence of poor adhesion but also reduce internal stress, as well as a method for producing polyimide, a method for producing a laminate, and a method for producing an electronic device using the polyamic acid composition.

The preferred embodiments of the present invention are described in detail below, but the present invention is not limited thereto. In addition, all the academic documents and patent documents described in this specification are introduced into this specification in the form of reference.

First, the terms used in this specification are explained. "Structural unit" refers to a repeating unit constituting a polymer. "Polyamide" refers to a polymer containing a structural unit represented by the following general formula (7) (hereinafter, sometimes described as "structural unit (7)").

[Chemical 3]

In the general formula (7), A ¹ represents a tetracarboxylic dianhydride residue (a tetravalent organic group derived from a tetracarboxylic dianhydride), and A ² represents a diamine residue (a divalent organic group derived from a diamine). .

The content of the structural unit (7) relative to all the structural units constituting polyamide is, for example, 50 mol % to 100 mol %, preferably 60 mol % to 100 mol %, more preferably 70 mol % to 100 mol %, further preferably 80 mol % to 100 mol %, further preferably 90 mol % to 100 mol %, and may also be 100 mol %.

"1% weight loss temperature" refers to the measurement temperature at which the weight of polyimide at a measurement temperature of 150°C is reduced by 1% by weight relative to the weight of the above reference (100% by weight). The method for measuring the 1% weight loss temperature is the same as the following examples or the method referring to the following examples.

"Alkyl" and "alkoxyalkyl" are both linear or branched and unsubstituted.

Hereinafter, "system" may be appended to the compound name to collectively refer to the compound and its derivatives. In addition, when "system" is appended to the compound name to represent the polymer name, unless otherwise specified, it means that the repeating units of the polymer are derived from the compound or its derivatives. Moreover, tetracarboxylic dianhydride may be described as "acid dianhydride". In addition, unless otherwise specified, the components, functional groups, etc. exemplified in this specification may be used alone or two or more types may be used in combination.

<Preferred embodiment of the present invention> The polyamine composition of the present embodiment comprises polyamine and an organic solvent. The polyamine contained in the polyamine composition of the present embodiment (hereinafter, sometimes referred to as "specific polyamine") has a residue containing a divalent organic group represented by the following chemical formula (1) (hereinafter, sometimes referred to as "residue (1)"), a 3,3',4,4'-biphenyltetracarboxylic dianhydride residue, and a p-phenylenediamine residue. The organic solvent contained in the polyamine composition of the present embodiment comprises one or more compounds selected from the group consisting of a compound represented by the following general formula (2) (hereinafter, sometimes referred to as "compound (2)") and a compound represented by the following general formula (3) (hereinafter, sometimes referred to as "compound (3)"). Hereinafter, one or more compounds (organic solvents) selected from the group consisting of compound (2) and compound (3) may be referred to as "specific organic solvent". Also, 3,3',4,4'-biphenyltetracarboxylic dianhydride may be referred to as "BPDA". Also, p-phenylenediamine may be referred to as "PDA".

[Chemistry 4]

In the general formula (2), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a monovalent organic group with a carbon number of 1 or more, and at least one of R ¹ , R ² and R ³ represents a carbon atom. 2 or more monovalent organic bases. Moreover, in the general formula (3), R ⁴ represents a monovalent organic group having 2 or more carbon atoms.

Generally speaking, in polyamide compositions, N,N-dimethylformamide, N-methyl-2-pyrrolidone, N,N- Dimethylacetamide and other amide solvents with relatively small carbon atoms are gradually recognized as harmful to health. In contrast, specific organic solvents have less impact on the environment or human body and are safer.

In order to improve safety, R ¹ , R ² and R ³ in the general formula (2) are each independently preferably a monovalent organic group having 1 or more carbon atoms, more preferably a monovalent organic group having 1 or more carbon atoms and less than 6 carbon atoms. In order to further improve safety, R ¹ and R ² in the general formula (2) are each independently preferably an alkyl group having 1 or more carbon atoms, more preferably an alkyl group having 1 or more carbon atoms and less than 6 carbon atoms. In order to further improve safety, R ³ in the general formula (2) is each independently preferably an alkoxyalkyl group having 2 or more carbon atoms, more preferably an alkoxyalkyl group having 2 or more carbon atoms and less than 6 carbon atoms.

In order to improve safety, R ⁴ in the general formula (3) is preferably a monovalent organic group having 2 to 6 carbon atoms. In order to further improve safety, R ⁴ in the general formula (3) is preferably an alkyl group having 2 to 6 carbon atoms.

Examples of compound (2) include 3-methoxy-N,N-dimethylpropionamide, 3-butoxy-N,N-dimethylpropionamide, N,N-diethylacetamide, and N,N-dimethylpropionamide. Among these, 3-methoxy-N,N-dimethylpropionamide and 3-butoxy-N,N-dimethylpropionamide are preferred from the viewpoint of safety.

Examples of the compound (3) include 1-ethyl-2-pyrrolidone and 1-butyl-2-pyrrolidone. Among these, 1-butyl-2-pyrrolidone is preferred from the viewpoint of safety.

The polyamide composition of this embodiment may include only compound (2) as a specific organic solvent, may include only compound (3) as a specific organic solvent, or may include both compound (2) and compound (3) As a specific organic solvent. In order to improve safety, as the specific organic solvent, 3-methoxy-N,N-dimethylpropylamide, 3-butoxy-N,N-dimethylpropylamide or 1-butylamine is preferred. base-2-pyrrolidone, more preferably 3-methoxy-N,N-dimethylpropylamine or 1-butyl-2-pyrrolidone.

The specific polyamide contains BPDA residues and PDA residues and therefore has a rigid structure. Therefore, certain polyamides are able to reduce internal stress.

On the other hand, according to the research of the inventors, it has been found that if a polyimide film is produced using a polyimide composition comprising a polyimide having a rigid structure and a specific organic solvent, ridges are easily generated at the interface between the polyimide film and the support. If ridges exist at the interface between the polyimide film and the support, there is a risk of causing the polyimide film to be peeled off when forming an electronic component, or a decrease in yield when the polyimide film is peeled off from the support after the electronic component is formed. Furthermore, the so-called "ridge" refers to a state in which poor adhesion occurs between the polyimide film and other material layers (more specifically, a glass substrate, a sacrificial layer, etc.) due to by-products or residual solvents generated during imidization. Specific examples of "protrusion" include a state where the polyimide film protrudes from the support, a state where a portion of the polyimide film is damaged and interlayer peeling occurs between the polyimide film and other material layers, and the like.

Generally speaking, the molecular chains of polyimide films obtained from polyamide having BPDA residues and PDA residues are closely packed, so if a solvent with a relatively large number of carbon atoms, such as a specific organic solvent, is used, it will appear The tendency of exhaust performance to deteriorate. Therefore, it is speculated that in the process of coating a polyamic acid composition containing a polyamic acid with a rigid structure on a support and performing imidization, residual solvent or detached molecules generated due to the imidization Being sealed, it is easy to cause bulges at the interface between the polyimide film and the support. In this regard, the inventors of the present invention conducted intensive studies, and as a result, it was found that if a polyamide (specific polyamide) having a BPDA residue, a PDA residue, and the residue (1) is used, it is possible to use the residues (1) The fluffy structure achieves good exhaust and can reduce internal stress. That is, according to the polyamic acid composition of this embodiment, since it contains a specific polyamic acid and a specific organic solvent, it is possible to use a relatively safe solvent and suppress the occurrence of poor adhesion due to good outgassing properties. , and can reduce internal stress.

The residue (1) is a residue contained in the polyamic acid, and is one or more residues selected from the group consisting of tetracarboxylic dianhydride residues and diamine residues. The specific polyamic acid may have only tetracarboxylic dianhydride residues as the residue (1), may have only diamine residues as the residue (1), or may have both tetracarboxylic dianhydride residues and diamine residues as the residue (1).

Examples of the tetracarboxylic dianhydride used to form the residue (1) include: spiro[11H-difuro[3,4-b:3',4'-i]𠮿 -11,9'-[9H]fluorine]-1,3,7,9-tetraketone (hereinafter sometimes referred to as "SFDA"), 9,9-bis(3,4-dicarboxyphenyl)fluorine Dianhydride (hereinafter, sometimes referred to as "BPAF"), 9,9-bis[4-(3,4-dicarboxyphenoxy)phenyl]fluoride dianhydride, 5,5'-[9H-fluoride- N ,N'-(9H-fluorine-9-ylidene-4,1-phenylene)bis[1,3-dihydro-1,3-dioxy-5-isobenzofuranmethamide base], 5,5'-spiro[9H-茀-9,9'-[9H]𠮿 ]-3',6'-diylbis(1,3-dihydro-1,3-bisoxy-5-isobenzofurancarboxylate), etc. In order to further suppress the occurrence of poor adhesion, SFDA or BPAF is preferred as the tetracarboxylic dianhydride used to form the residue (1).

Examples of the diamine used to form the residue (1) include 9,9-bis(4-aminophenyl)fluorene (hereinafter, sometimes referred to as "BAFL"), 3,3'-(9H-fluorene-9,9-diyl)diphenylamine, and 4,4'-(9H-fluorene-9-ylidene)bis[2-fluoroaniline]. In order to further suppress the occurrence of poor adhesion, BAFL is preferably used as the diamine used to form the residue (1).

In order to further suppress the occurrence of poor adhesion, the residue (1) is preferably one or more residues selected from the group consisting of SFDA residues, BPAF residues and BAFL residues. The SFDA residue is a tetravalent organic group represented by the following chemical formula (4). The BPAF residue is a tetravalent organic group represented by the following chemical formula (5). The BAFL residue is a bivalent organic group represented by the following chemical formula (6).

[Chemistry 5]

Among them, the SFDA residue has origin from 𠮿 The structure has a rigid structure, so in order to further reduce internal stress and further suppress the occurrence of poor adhesion, the SFDA residue is particularly preferred as the residue (1).

In order to suppress an increase in the thermal expansion coefficient, the content rate of the residue (1) (the equal total content rate when multiple types of residues (1) are included) is determined relative to all the tetracarboxylic acids constituting the specific polyamic acid. The total of dianhydride residues and all diamine residues constituting the specific polyamide acid is 100 mol%, preferably 15 mol% or less, more preferably 10 mol% or less, and may also be 5 mol% or less. . In addition, in order to further suppress the occurrence of poor adhesion, the content rate of the residue (1) (when a plurality of types of residues (1) is included, the total content rate of the same) is determined relative to all the components constituting the specific polyamide. The total of tetracarboxylic dianhydride residues and all diamine residues constituting the specific polyamide acid is 100 mol%, preferably 0.1 mol% or more, more preferably 0.5 mol% or more, and still more preferably 1 More than mol%.

When synthesizing the specific polyamide, an acid dianhydride other than BPDA and the acid dianhydride used to form the residue (1) may be used as a monomer within a range that does not impair its performance. Examples of the acid dianhydride other than BPDA and the acid dianhydride used to form the residue (1) include pyromellitic acid dianhydride, p-phenylenediphenyl trimellitic acid dianhydride, 1,2,5,6-naphthalenetetracarboxylic acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic acid dianhydride, 2,2',3,3'-biphenyltetracarboxylic acid dianhydride, 3,3',4,4'-benzophenonetetracarboxylic acid dianhydride, 4,4'-oxydiphthalic acid anhydride, dicyclohexyl -3,3',4,4'-tetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2'-oxodispiro[bicyclo[2.2.1]heptane-2,1'-cyclopentane-3',2''-bicyclo[2.2.1]heptane]-5,6:5'',6''-tetracarboxylic dianhydride and derivatives thereof may be used alone or in combination of two or more.

In order to further reduce internal stress, the content rate of BPDA residues is preferably 70 mol% or more relative to the total amount of tetracarboxylic dianhydride residues constituting the specific polyamide (100 mol%), and more preferably 80 mol% or more, more preferably 90 mol% or more, and 100 mol% may also be used.

In the case where the residue (1) is a residue derived from an acid dianhydride (SFDA residue, BPAF residue, etc.), in order to further suppress the occurrence of poor adhesion, the content of the residue (1) is preferably 0.1 mol% or more, more preferably 0.5 mol% or more, relative to the total amount (100 mol%) of tetracarboxylic dianhydride residues constituting the specific polyamide. In addition, in the case where the residue (1) is a residue derived from an acid dianhydride (SFDA residue, BPAF residue, etc.), in order to further reduce the internal stress, the content of the residue (1) is preferably 10 mol% or less, more preferably 8 mol% or less, relative to the total amount (100 mol%) of tetracarboxylic dianhydride residues constituting the specific polyamide.

In order to further suppress the occurrence of poor adhesion and further reduce internal stress, the total content rate of the residue (1) derived from the acid dianhydride and the BPDA residue is determined relative to the tetracarboxylic dianhydride residue constituting the specific polyamide. The total amount (100 mol%) is preferably 60 mol% or more, more preferably 70 mol% or more, further preferably 80 mol% or more, particularly preferably 90 mol% or more, and may be 100 Mol%.

In the synthesis of the specific polyamide, diamines other than PDA and the diamine used to form the residue (1) may be used as monomers within the range that the performance is not impaired. Examples of diamines other than PDA and the diamine used to form the residue (1) include: 4-aminophenyl 4-aminobenzoate, 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl ether, 1,4-cyclohexanediamine, 4,4'-diaminobenzanilide, m-phenylenediamine, 4,4'-oxydiphenylamine, 3,4'-oxydiphenylamine, N,N'-bis(4-aminophenyl)-p-phenylenediamine, 4,4'-diaminodiphenylsulfone, intermolecularly linked diamine, Toluidine, o-tolidine, 4,4'-bis(4-aminophenoxy)biphenyl, 2-(4-aminophenyl)-6-aminobenzoxazole, 3,5-diaminobenzoic acid, 4,4'-diamino-3,3'-dihydroxybiphenyl, 4,4'-methylenebis(cyclohexylamine), 1,3-bis(3-aminopropyl)tetramethyldisiloxane (hereinafter, sometimes referred to as "PAM-E"), and derivatives thereof may be used alone or in combination of two or more.

In order to improve the adhesion between the polyimide film and the support, PAM-E is preferred as the diamine other than PDA and the diamine used to form the residue (1). That is, in order to improve the adhesion between the polyimide film and the support, the specific polyamide preferably has a PAM-E residue.

In order to further improve the adhesion between the polyimide film and the support, the content of the PAM-E residue is preferably 0.05 mol% or more, more preferably 0.1 mol% or more, and can also be 0.2 mol% or more relative to the total amount (100 mol%) of the diamine residues constituting the specific polyamide. In addition, in order to suppress the decrease in yield when the polyimide film is peeled off from the support after forming the electronic element, the content of the PAM-E residue is preferably 1.0 mol% or less, more preferably 0.9 mol% or less, further preferably 0.8 mol% or less, further preferably 0.7 mol% or less, and can also be 0.6 mol% or less relative to the total amount (100 mol%) of the diamine residues constituting the specific polyamide.

In order to further reduce the internal stress, the content of PDA residues relative to the total amount of diamine residues constituting the specific polyamide (100 mol %) is preferably 70 mol % or more, more preferably 80 mol % or more, further preferably 90 mol % or more, and can also be 100 mol %.

When the residue (1) is a residue derived from a diamine (BAFL residue, etc.), in order to further suppress the occurrence of poor adhesion, the content rate of the residue (1) is determined relative to the content of the residue constituting the specific polyamide. The total amount of diamine residues (100 mol%) is preferably 0.1 mol% or more, more preferably 0.5 mol% or more. In addition, when the residue (1) is a residue derived from a diamine (BAFL residue, etc.), in order to further reduce the internal stress, the content rate of the residue (1) is determined relative to the second component of the specific polyamide. The total amount of amine residues (100 mol%) is preferably 10 mol% or less, more preferably 8 mol% or less, and still more preferably 5 mol% or less.

In order to further suppress the occurrence of poor adhesion and further reduce internal stress, the total content rate of the diamine-derived residue (1) and the PDA residue is determined relative to the total amount of diamine residues constituting the specific polyamide (100 Mol%), preferably 60 Mol% or more, more preferably 70 Mol% or more, further preferably 80 Mol% or more, particularly preferably 90 Mol% or more, and may be 100 Mol%.

When the specific polyamide has PAM-E residues, in order to obtain a polyamide composition that can further suppress the occurrence of poor adhesion and further reduce internal stress, and can further improve the adhesion between the polyimide film and the support, the total content of PAM-E residues, diamine-derived residues (1) and PDA residues is preferably 60 mol% or more, more preferably 70 mol% or more, further preferably 80 mol% or more, particularly preferably 90 mol% or more, and can also be 100 mol% relative to the total amount of diamine residues constituting the specific polyamide (100 mol%).

In order to further reduce the internal stress and further suppress the occurrence of poor adhesion, the specific polyamide preferably satisfies the following condition 1, more preferably satisfies the following condition 2, further preferably satisfies the following condition 3, and particularly preferably satisfies the following condition 4. Condition 1: The total content of the residue (1), BPDA residue and PDA residue is 90 mol% or more relative to the total of 100 mol% of all tetracarboxylic dianhydride residues constituting the specific polyamide and all diamine residues constituting the specific polyamide. Condition 2: Satisfy the above condition 1 and further have a PAM-E residue. Condition 3: The above condition 2 is satisfied, and the content of PAM-E residues is 0.1 mol% or more and 1.0 mol% or less relative to the total amount of diamine residues constituting the specific polyamide (100 mol%). Condition 4: The above condition 3 is satisfied, and the total content of residues (1), BPDA residues, PDA residues and PAM-E residues is 95 mol% or more and 100 mol% or less relative to the total of all tetracarboxylic dianhydride residues constituting the specific polyamide and all diamine residues constituting the specific polyamide (100 mol%).

The specific polyamide can be synthesized by a known general method, for example, by reacting a diamine with a tetracarboxylic dianhydride in an organic solvent. An example of a specific synthesis method of the specific polyamide is described. First, in an atmosphere of an inert gas such as argon or nitrogen, a diamine is dissolved or dispersed in an organic solvent in a slurry form to prepare a diamine solution. Then, the tetracarboxylic dianhydride is added to the above diamine solution after being dissolved or dispersed in an organic solvent in a slurry form, or in a solid state.

When using diamine and tetracarboxylic dianhydride to synthesize a specific polyamide, by adjusting the amount of diamine (when using multiple diamines, the amount of each diamine) and the amount of tetracarboxylic acid The amount of acid dianhydride (when using a plurality of tetracarboxylic dianhydrides, the amount of each tetracarboxylic dianhydride) can obtain the desired specific polyamide (diamine and tetracarboxylic dianhydride). anhydride polymer). The molar fraction of each residue in a specific polyamic acid is, for example, consistent with the molar fraction of each monomer (diamine and tetracarboxylic dianhydride) used in the synthesis of the polyamic acid. Furthermore, by blending two types of polyamic acids, a specific polyamic acid containing a plurality of tetracarboxylic dianhydride residues and a plurality of diamine residues can be obtained. The temperature conditions of the reaction between diamine and tetracarboxylic dianhydride, that is, the synthesis reaction of the specific polyamide, are not particularly limited, but are, for example, in the range of 20°C or more and 150°C or less. The reaction time for the synthesis reaction of a specific polyamide is, for example, in the range of from 10 minutes to 30 hours.

The organic solvent used in the synthesis of the specific polyamic acid is preferably a solvent that can dissolve the tetracarboxylic dianhydride and diamine used, and more preferably a solvent that can dissolve the specific polyamic acid to be produced. As an organic solvent used for the synthesis of specific polyamide, from the viewpoint of safety, the above-mentioned specific organic solvent is preferred. In addition, in the synthesis of the specific polyamide, organic solvents other than the specific organic solvent may also be used. Examples of organic solvents other than the specific organic solvent include urea-based solvents such as tetramethylurea and N,N-dimethylethylurea; teresine-based solvents such as dimethyl teresine; Methyl alcohol and other methyl solvents; N,N-dimethylacetamide (DMAC), N,N-dimethylformamide (DMF), N-methyl-2-pyrrolidone (NMP), Amide solvents other than specific organic solvents such as hexamethylphosphotriamine; ester solvents such as γ-butyrolactone; halogenated alkyl solvents such as chloroform and dichloromethane; aromatic hydrocarbon solvents such as benzene and toluene ; Phenolic solvents such as phenol and cresol; Ketone solvents such as cyclopentanone; Tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, dimethyl ether, diethyl ether, diethylene glycol diethyl ether , diethylene glycol dimethyl ether, p-cresol methyl ether and other ether solvents. These solvents are usually used alone, but two or more of them may be used in appropriate combination as necessary. In addition, the synthesis reaction of the specific polyamide is preferably carried out under an inert gas atmosphere such as argon or nitrogen.

The polyamine composition of the present embodiment contains a specific polyamine and a specific organic solvent. When the specific polyamine is obtained by the above method, the reaction solution (solution after the reaction) itself can also be used as the polyamine composition of the present embodiment. When the reaction solution itself is used as the polyamine composition of the present embodiment, the organic solvent used to synthesize the specific polyamine is preferably the above-mentioned specific organic solvent. In addition, the solid specific polyamine obtained by removing the solvent from the reaction solution can be dissolved in a specific organic solvent to prepare the polyamine composition of the present embodiment.

The polyamine composition of the present embodiment may also contain an organic solvent other than the specific organic solvent. Among them, from the perspective of safety, the content of the specific organic solvent in the polyamine composition of the present embodiment is preferably 70% by weight or more, more preferably 80% by weight or more, further preferably 90% by weight or more, and particularly preferably 100% by weight relative to the total amount of the organic solvent in the polyamine composition. Furthermore, the content of the specific polyamine in the polyamine composition of the present embodiment is not particularly limited, for example, it is 1% by weight or more and 80% by weight or less relative to the total amount of the polyamine composition.

The weight average molecular weight of the specific polyamine is preferably in the range of 10,000 to 1,000,000, more preferably in the range of 20,000 to 500,000, and further preferably in the range of 30,000 to 200,000, but it also depends on its use. If the weight average molecular weight is 10,000 or more, it is easy to make a coating film or a polyimide film (film) from the specific polyamine or the polyimide obtained using the specific polyamine. On the other hand, if the weight average molecular weight is 1,000,000 or less, it shows sufficient solubility in the solvent, so the following polyamine composition can be used to obtain a coating film or a polyimide film with a smooth surface and uniform thickness. The weight average molecular weight used here refers to the polyethylene oxide equivalent value measured by gel permeation chromatography (GPC).

In addition, as a method of controlling the molecular weight of a specific polyamic acid, there can be exemplified a method of making an excess of either an acid dianhydride or a diamine, or a method of controlling the molecular weight of a specific polyamic acid with a monofunctional acid anhydride such as phthalic anhydride or aniline. Or a method of quenching the reaction by reacting with an amine. When polymerizing an acid dianhydride or a diamine in an excess amount, a polyimide film with sufficient strength can be obtained if the molar ratio of the two is between 0.95 and 1.05. Furthermore, the above-mentioned feed molar ratio is the ratio of the total amount of diamines used in the synthesis of the specific polyamic acid to the total amount of the acid dianhydride used in the synthesis of the specific polyamic acid (diamine The total material quantity/the total material quantity of acid dianhydride). Furthermore, by terminal capping with phthalic anhydride, maleic anhydride, aniline, etc., the coloring of the polyimide obtained using a specific polyamide can be further reduced.

Furthermore, the polyamide composition of the present embodiment may also contain an imidization accelerator and/or a dehydration catalyst in order to shorten the heating time or improve the performance.

The above-mentioned imidization accelerator is not particularly limited, and a tertiary amine can be used. As the tertiary amine, a heterocyclic tertiary amine is preferred. Preferred specific examples of the heterocyclic tertiary amine include pyridine, picoline, quinoline, isoquinoline, and imidazoles. Preferred specific examples of the above-mentioned dehydration catalyst include acetic anhydride, propionic anhydride, n-butyric anhydride, benzoic anhydride, and trifluoroacetic anhydride.

From the viewpoint of shortening the heating time and the viewpoint of showing the characteristics, the amount of the imidization accelerator is preferably 0.1 to 20 parts by weight, more preferably 0.5 to 20 parts by weight, based on 100 parts by weight of the specific polyamide. Also, from the viewpoint of shortening the heating time and the viewpoint of showing the characteristics, the amount of the dehydration catalyst is preferably 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the specific polyamide.

As the imidization accelerator, imidazoles are preferred. In addition, in this specification, imidazoles refer to the compound which has a 1,3-oxadiazole ring (1,3-oxadiazole ring structure). The imidazoles that can be added to the polyamic acid composition of this embodiment are not particularly limited, and examples thereof include: 1H-imidazole, 2-methylimidazole, 2-undecylimidazole, 2-decane Heptalkyl imidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methyl 1-Benzyl imidazole, 1-benzyl-2-phenylimidazole, etc. Among these, 1,2-dimethylimidazole, 1-benzyl-2-methylimidazole, and 1-benzyl-2-phenylimidazole are preferred, and 1,2-dimethylimidazole is more preferred. , 1-benzyl-2-methylimidazole.

The content of imidazoles is preferably 0.005 mol or more and 0.1 mol or less, more preferably 0.01 mol or more and 0.08 mol or less, and further preferably 0.015 mol or more and 0.050 mol or less, relative to 1 mol of the amide group of the specific polyamide. By containing 0.005 mol or more of imidazoles, the film strength and transparency of the polyimide can be improved, and by making the content of imidazoles 0.1 mol or less, the storage stability of the specific polyamide can be maintained and the heat resistance can be improved. Furthermore, in this specification, "amide groups of specific polyamides" refer to amide groups generated by the polymerization reaction of diamines and tetracarboxylic dianhydride.

The mixing method of the specific polyamide and imidazoles is not particularly limited. From the viewpoint of ease of controlling the molecular weight of the specific polyamic acid, it is preferable to add imidazoles to the specific polyamic acid after polymerization. At this time, imidazoles can be added directly to the specific polyamic acid, or imidazoles can be dissolved in a solvent in advance and the solution can be added to the specific polyamic acid. The adding method is not particularly limited. The polyamic acid composition of this embodiment can also be prepared by adding imidazoles to a solution containing a specific polyamic acid after polymerization (solution after reaction).

In the polyamide composition of the present embodiment, various organic or inorganic low molecular weight compounds or high molecular weight compounds may also be formulated as additives. As additives, for example, plasticizers, antioxidants, dyes, surfactants, leveling agents, silicones, microparticles, sensitizers, etc. may be used. Microparticles include organic microparticles containing polystyrene, polytetrafluoroethylene, etc., or inorganic microparticles containing colloidal silicon oxide, carbon, layered silicate, etc., which may also be porous structures or hollow structures. In addition, the function and morphology of the microparticles are not particularly limited, for example, they may be pigments, fillers, or fiber-like particles.

In order to express appropriate adhesion with the support, the polyamic acid composition of the present embodiment may contain a silane coupling agent. As the silane coupling agent, a known silane coupling agent can be used without particular limitation. In order to exhibit good adhesion with the support, the silane coupling agent that can be used is preferably a compound containing an amine group, and more preferably a compound selected from the group consisting of 3-aminopropyltrimethoxysilane and 3-aminopropyltrimethoxysilane. Triethoxysilane, 3-aminopropyldiethoxymethylsilane, 3-(ethoxydimethylsilyl)propylamine, N-2-(aminoethyl)-3-amino Composed of propyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane and N-phenyl-3-aminopropyltrimethoxysilane One or more compounds in the group, and more preferably one or more compounds selected from the group consisting of 3-aminopropyltriethoxysilane and 3-aminopropyldiethoxymethylsilane, Particularly preferred is 3-aminopropyltriethoxysilane.

The mixing ratio of the silane coupling agent to 100 parts by weight of the specific polyamide is preferably 0.01 parts by weight to 0.50 parts by weight, more preferably 0.01 parts by weight to 0.30 parts by weight, and further preferably 0.01 parts by weight to 0.20 parts by weight. By making the mixing ratio of the silane coupling agent 0.01 parts by weight or more, the peeling-inhibiting effect on the support can be fully exerted, and by making the mixing ratio of the silane coupling agent 0.50 parts by weight or less, the molecular weight reduction of the specific polyamide can be suppressed, thereby suppressing the embrittlement of the polyimide film.

In organic solvents with a high pH value such as 3-methoxy-N,N-dimethylpropionamide, the reaction rate of the silane coupling agent may increase. Since it is difficult to control the condensation reaction of the generated silanol group, it is better to reduce the number of alkoxy groups as needed or use a silane coupling agent with a less reactive alkoxy group. Specifically, by using 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 3-(ethoxydimethylsilyl)propylamine, etc., the condensation reaction of the silanol group can be controlled and good adhesion and releasability with the support can be achieved.

The method for producing polyimide of the present embodiment comprises the step of heating the polyamic acid composition of the present embodiment to imidize the specific polyamic acid. There is no particular limitation on the method for imidizing the specific polyamic acid, and a known method can be used. Hereinafter, an example of a method for imidizing the specific polyamic acid is described. The imidization is carried out by dehydrating and ring-closing the specific polyamic acid. The dehydration and ring-closing can be carried out by an azeotropic method using an azeotropic solvent, a thermal method, or a chemical method. Alternatively, the polyamine composition can be directly placed in a container that has been subjected to plasma treatment with a fluorine resin, and the polyamine composition can be heated and dried under reduced pressure to perform dehydration and ring-closing of a specific polyamine. By performing dehydration and ring-closing of a specific polyamine using these methods, polyimide can be obtained. Furthermore, the heating time of each of the above treatments varies depending on the amount of the polyamine composition to be dehydrated and ring-closed or the heating temperature, but in general, it is preferably set to a range of more than 1 minute and less than 300 minutes after the treatment temperature reaches the highest temperature.

Moreover, the imidization from a specific polyamic acid to a polyimide can be set to any ratio of 1% or more and 100% or less. That is, it is also possible to synthesize a specific polyamide partially imidized. Especially when imidization is performed by raising the temperature by heating, the ring-closing reaction from a specific polyamic acid to a polyimide proceeds simultaneously with the hydrolysis of the specific polyamic acid, so that a polyimide can be produced. It is possible that the molecular weight is lower than the molecular weight of the specific polyamic acid. Therefore, before forming the following polyimide film, a part of the specific polyamic acid in the polyamic acid composition is imidized in advance. It is preferable from the viewpoint of improving mechanical properties. In this specification, a partially imidized polyamide may also be referred to as "polyamic acid".

The manufacturing method of the laminated body of this embodiment is a manufacturing method of the laminated body which has a support and a polyimide film (specifically, a polyimide film containing the imide compound of a specific polyamide). In the manufacturing method of the laminated body of this embodiment, by heating a specific polyamic acid, the specific polyamic acid is dehydrated and ring-closed, and is imidized. The method of heating the specific polyamic acid is not particularly limited. For example, the following method can be used: by coating the polyamic acid composition of the present embodiment on a support to form a mixture containing the specific polyamic acid. The coating film obtained is subjected to heat treatment at a temperature ranging from 40°C to 500°C, for example. Examples of the support include a glass substrate, a metal plate, a PET film (polyethylene terephthalate film), or a glass substrate with an amorphous silicon layer (a-Si layer) and a sacrificial layer. Glass substrate, etc. According to this method, a laminated body having a support and a polyimide film (specifically, a polyimide film containing an imide compound of a specific polyamide acid) disposed on the support can be obtained.

The polyimide film (specifically, the polyimide film containing the imide compound of a specific polyamic acid) formed by the manufacturing method of the laminate of the present embodiment is colorless, transparent, and has a low yellowness, and has a glass transition temperature (heat resistance) that can withstand the TFT manufacturing step, so it is suitable for a transparent substrate material for a flexible display. The content of the polyimide (specifically, the imide compound of a specific polyamic acid) in the polyimide film is, for example, 70% by weight or more, preferably 80% by weight or more, more preferably 90% by weight or more, and may be 100% by weight, relative to the total amount of the polyimide film. As components other than polyimide in the polyimide film, for example, the above-mentioned additives (more specifically, fine particles etc.) can be mentioned.

The manufacturing method of an electronic device (more specifically, a flexible device, etc.) of this embodiment includes step Sa, which is to heat the polyamic acid composition of this embodiment to melt a specific polyamic acid. Amination; and step Sb, which is to configure electronic components on the polyimide film obtained by step Sa. Step Sa is, for example, the same as the manufacturing method of the laminated body of this embodiment mentioned above. In step Sb, for example, an electronic component (TFT, etc.) is directly or indirectly disposed on the polyimide film obtained in step Sa.

When manufacturing electronic devices for use in flexible displays, first, an inorganic substrate such as glass is used as a support, and a polyimide film is formed on it. Then, electronic components such as TFTs are arranged (formed) on the polyimide film to form an electronic device on the support. The step of forming a TFT is usually carried out in a wide temperature range of 150°C to 650°C. However, in order to substantially achieve the desired performance, the oxide semiconductor layer or a-Si (amorphous silicon) is formed at 300°C or higher. layer, depending on the situation, a-Si, etc. may be further crystallized using laser or the like.

At this time, when the thermal decomposition temperature of the polyimide film is low, outgassing may be generated during the process of forming electronic components. This outgassing will adhere to the oven in the form of sublimates and cause contamination in the oven. , or the inorganic film (barrier film described below, etc.) or electronic components formed on the polyimide film is peeled off, so the 1% weight loss temperature of polyimide is preferably 500°C or above. The higher the upper limit of the 1% weight reduction temperature of polyimide, the better, for example, 600°C. The 1% weight loss temperature can be adjusted, for example, by changing the content rate of residues having a rigid structure (more specifically, BPDA residues, PDA residues, etc.). To explain in further detail, before forming the TFT, an inorganic film such as a silicon oxide film (SiOx film) or a silicon nitride film (SiNx film) is formed as a barrier film on the polyimide film. At this time, when the heat resistance of the polyimide is low, imidization is not completely progressed, or when there is a large amount of residual solvent, the polyimide may be lost during the high-temperature process after laminating the inorganic film. The decomposition gas of amine and other volatile components cause the polyimide to peel off the inorganic film. Therefore, it is ideal that in addition to the 1% weight reduction temperature of the polyimide being 500°C or higher, the weight reduction rate when the polyimide is isothermally maintained at a temperature in the range of 400°C to 450°C should not reach 1%.

In addition, when the glass transition temperature (Tg) of polyimide is significantly lower than the process temperature, positional deviation may occur during the process of forming electronic components, so the Tg of polyimide is preferably 300°C or higher, more preferably 350°C or higher, further preferably 400°C or higher, further preferably 420°C or higher. The higher the upper limit of the Tg of polyimide, the better, for example, 470°C. In addition, generally speaking, the thermal expansion coefficient of the glass substrate is smaller than that of the resin, so internal stress is generated between the glass substrate and the polyimide film. If the internal stress of the laminate of the glass substrate or electronic components and the polyimide film used as a support is high, the laminate including the polyimide film will expand during the high-temperature TFT formation step, and then shrink when cooled to room temperature, resulting in problems such as warping or damage of the glass substrate and peeling of the polyimide film from the glass substrate. Therefore, in the laminate having a support and a polyimide film, the internal stress between the polyimide film and the support is preferably 40 MPa or less, more preferably 30 MPa or less, further preferably 20 MPa, and particularly preferably 10 MPa or less. The lower the lower limit of the internal stress, the better, and it may be 0 MPa. The internal stress is determined by the same method as in the following embodiment or a method based thereon.

The polyimide obtained by the manufacturing method of this embodiment can be favorably used as a material for display substrates such as TFT substrates and touch panel substrates. When polyimide is used for the above-mentioned purposes, in most cases, an electronic device is formed on a support as described above (specifically, an electronic device in which electronic components are formed on a polyimide film) is then formed. Method for peeling polyimide film from support. In addition, as the material of the support, alkali-free glass is suitably used. Hereinafter, an example of a method for producing a laminate of a polyimide film and a support will be described in detail.

First, the polyamic acid composition of this embodiment is coated (cast) on a support to form a laminate including a coating film containing a specific polyamide and a coating film on the support. Next, the laminated body containing the coating film is heated under conditions such as a temperature of not less than 40°C and not more than 200°C. The heating time at this time is, for example, 3 minutes or more and 120 minutes or less. Furthermore, a multi-stage heating step can also be provided, for example, the laminate containing the coating film is heated at a temperature of 50°C for 30 minutes, and then heated at a temperature of 100°C for 30 minutes. Next, in order to promote the imidization of the specific polyamic acid in the coating film, the laminate containing the coating film is heated under conditions such as a maximum temperature of 200°C or more and 500°C or less. The heating time at this time (heating time at the highest temperature) is, for example, from 1 minute to 300 minutes. At this time, it is preferable to gradually increase the temperature from low temperature to the highest temperature. The temperature rising rate is preferably 2°C/min or more and 10°C/min or less, more preferably 4°C/min or more and 10°C/min or less. Moreover, the maximum temperature is preferably in the range of 250°C or more and 480°C or less. If the maximum temperature is 250° C. or higher, the imidization proceeds sufficiently, and if the maximum temperature is 480° C. or lower, thermal deterioration or coloring of the polyimide can be suppressed. In addition, it can also be maintained at any temperature for any time before reaching the maximum temperature. The imidization reaction can be carried out under air, under reduced pressure, or in an inert gas such as nitrogen. In order to exhibit higher transparency, it is preferably carried out under reduced pressure or in an inert gas such as nitrogen. In addition, as the heating device, known devices such as hot air oven, infrared oven, vacuum oven, non-oxidation oven, and heating plate can be used. Through these steps, the specific polyamic acid in the coating film is imidized, and a laminate of a support and a polyimide film (a film containing an imide compound of the specific polyamic acid) can be obtained.

The method of peeling the polyimide film from the obtained support and the laminate of the polyimide film can use a known method. For example, it can be peeled off by hand, or it can be peeled off using a mechanical device such as a drive roller or a robot. Furthermore, a method of providing a peeling layer between the support and the polyimide film can also be adopted; or a method of peeling the polyimide film by forming a silicon oxide film on a substrate having a plurality of grooves, forming a polyimide film with the silicon oxide film as a base layer, and allowing an etching solution of silicon oxide to penetrate between the substrate and the silicon oxide film. In addition, a method of separating the polyimide film by irradiating laser light can also be adopted.

The transparency of the polyimide film can be evaluated by the total light transmittance (TT) according to JIS K7361-1:1997 and the haze according to JIS K7136-2000. When the polyimide film is used for applications requiring high transparency, the total light transmittance of the polyimide film is preferably 75% or more, more preferably 80% or more. Furthermore, when the polyimide film is used for applications requiring high transparency, the haze of the polyimide film is preferably 1.5% or less, more preferably 1.2% or less, further preferably 1.0% or less, and may be 0%. In applications requiring high transparency, polyimide films are required to have a higher transmittance in the entire wavelength range, but polyimide films tend to easily absorb light on the short wavelength side, and the film itself is often colored yellow. In order to use polyimide films for applications requiring high transparency, it is better to reduce the coloring of the polyimide film. Specifically, in order to use polyimide films for applications requiring high transparency, the yellowness (YI) of the polyimide film is preferably 25 or less, more preferably 20 or less, and can also be 0. YI can be measured in accordance with JIS K7373-2006. YI can be adjusted, for example, by changing the content of the residue (1) in the specific polyamide acid. Thus, the polyimide film with reduced coloration and given transparency is suitable for transparent substrates for use as glass substitutes, or substrates with sensors or camera modules provided on the back.

Furthermore, among the light extraction methods of the flexible display, there are two types: a top emission method that extracts light from the front side of the TFT and a bottom emission method that extracts light from the back side of the TFT. The top emission method has the characteristics of being easy to increase the aperture ratio because the light is not blocked by the TFT, and being able to obtain high-precision image quality. The bottom emission method has the characteristics of being easy to align the position of the TFT and the pixel electrode and being easy to manufacture. If the TFT is transparent, the aperture ratio can also be increased in the bottom emission method, so large displays tend to adopt the bottom emission method that is easy to manufacture. The polyimide film obtained by the manufacturing method of this embodiment has a lower YI and excellent heat resistance, so it can be applied to any of the above-mentioned light extraction methods.

In a batch device manufacturing process in which a polyimide composition is coated on a support such as a glass substrate and heated to be imidized to form electronic components, the polyimide film is peeled off, and it is preferred that the adhesion between the support and the polyimide film is excellent. The adhesion here refers to the adhesion strength. In a manufacturing process in which electronic components are formed on the polyimide film on the support, the polyimide film formed with the electronic components is peeled off from the support, if the adhesion between the polyimide film and the support is excellent, the electronic components can be formed or mounted more accurately. In the manufacturing process of arranging electronic components on a support with a polyimide film interposed therebetween, from the viewpoint of improving productivity, the peel strength between the support and the polyimide film is preferably 0.05 N/cm or more, more preferably 0.1 N/cm or more. The method for measuring the peel strength is the same as the method in the following embodiment or a method based thereon.

In the manufacturing process described above, when the polyimide film is peeled off from the support and the laminate of the polyimide film, in most cases, the polyimide film is peeled off from the support by laser irradiation. In this case, the polyimide film must absorb the laser light, so the cutoff wavelength of the polyimide film is required to be longer than the wavelength of the laser light used for peeling. Laser stripping often uses a XeCl excimer laser with a wavelength of 308 nm, so the cutoff wavelength of the polyimide film is preferably above 312 nm, and more preferably above 330 nm. On the other hand, if the cutoff wavelength is a long wavelength, the polyimide film will tend to be colored yellow, so the cutoff wavelength of the polyimide film is preferably below 390 nm. From the perspective of both transparency (low yellowness) and laser stripping processability, the cutoff wavelength of the polyimide film is preferably 320 nm to 390 nm, more preferably 330 nm to 380 nm. In addition, the cutoff wavelength in this specification refers to the wavelength at which the transmittance measured by an ultraviolet-visible spectrophotometer becomes 0.1% or less.

The polyamide composition of this embodiment and the polyimide obtained by the manufacturing method of this embodiment can be directly used in the coating or forming process for making products or components, but they can also be used for manufacturing products or components. A material that is formed into a film and further processed by coating. In order to be used in the coating or forming process, the polyamic acid composition or polyimide can also be dissolved or dispersed in an organic solvent as needed, and further, photo-curable components, thermosetting components, and non-polymerizable components can be prepared as necessary. Adhesive resins and other ingredients are used to prepare compositions containing specific polyamides or polyimides.

Various inorganic thin films such as a metal oxide film or a transparent electrode can also be formed on the surface of the polyimide film obtained by the manufacturing method of this embodiment. The method of forming the inorganic thin film is not particularly limited, and examples thereof include PVD (Physical Vapor Deposition) methods such as sputtering, vacuum evaporation, and ion plating, or CVD (Physical Vapor Deposition). Chemical Vapor Deposition, chemical vapor deposition) method.

The polyimide film obtained by the manufacturing method of the present embodiment has heat resistance, low thermal expansion, and transparency. When forming a laminate with a glass substrate, the internal stress generated is also small, and the close contact with inorganic materials can be ensured during the high-temperature process. Therefore, it is preferably used in fields and products where these characteristics can be brought into play. For example, the polyimide film obtained by the manufacturing method of the present embodiment is preferably used in liquid crystal display devices, organic EL, electronic paper and other image display devices, printed materials, color filters, flexible displays, optical films, 3D displays, touch panels, transparent conductive film substrates, solar cells, etc., and further, it is more preferably used as a substitute material for parts currently using glass. In such applications, the thickness of the polyimide film is, for example, 1 μm to 200 μm, preferably 5 μm to 100 μm. The thickness of the polyimide film can be measured using a laser holo gauge.

Furthermore, the polyamide composition of the present embodiment can be well used in the following method for producing a polyimide film: the polyamide composition is coated on a support, heated to be imidized, and then the polyimide film is peeled off from the support. Furthermore, the polyamide composition of the present embodiment can be well used in the following batch device manufacturing process: the polyamide composition is coated on a support, heated to be imidized, and then electronic components, etc. are formed on the formed polyimide film, and then the polyimide film formed with the electronic components, etc. is peeled off from the support. Therefore, the method for producing an electronic device of the present embodiment can also include the step of peeling the polyimide film formed with the electronic components, etc. from the support. [Example]

Hereinafter, embodiments of the present invention will be described, but the scope of the present invention is not limited to the following embodiments.

<Methods for measuring and evaluating physical properties> First, the methods for measuring and evaluating physical properties of polyimide (polyimide film) are explained.

[Internal stress] On a glass substrate manufactured by Corning Incorporated (trade name: Eagle XG, material: alkali-free glass, thickness: 0.7 mm, size: 100 mm×100 mm) whose warp was measured in advance, each polyamide composition prepared in the following embodiments and comparative examples was coated using a rotary coater, and then heated at 120°C for 30 minutes in air and then heated at 460°C for 45 minutes in a nitrogen atmosphere to obtain a laminate having a polyimide film with a thickness of 10 μm on the glass substrate. In order to eliminate the influence of water absorption of the polyimide film, the laminate was dried at 120°C for 10 minutes, and then the warp of the laminate was measured in a nitrogen atmosphere at a temperature of 25°C using a thin film stress measuring device ("FLX-2320-S" manufactured by KLA-Tencor). Then, based on the warp of the glass substrate before the polyimide film was formed and the warp of the laminate, the internal stress generated between the glass substrate and the polyimide film was calculated using the Stoney formula. When the internal stress is below 30 MPa, it is evaluated as "the internal stress can be reduced". On the other hand, when the internal stress exceeds 30 MPa, it is evaluated as "the internal stress cannot be reduced".

[1% weight loss temperature (TD1)] The polyimide film sampled from each laminate obtained in the following Examples and Comparative Examples (specifically, the polyimide film sampled so that the weight became 10 mg) was used as a measurement sample, Using a differential thermogravimetric simultaneous measurement device ("TG/DTA7200" manufactured by Hitachi High-Tech Science Co., Ltd.), in a nitrogen atmosphere, the temperature was increased from 25°C to 650°C at a rate of 20°C/min, and the measurement was performed at 150°C. The weight of the sample at the temperature is used as the basis, and the measurement temperature when the weight is reduced by 1% by weight relative to the basis is regarded as the 1% weight reduction temperature (TD1).

[Film-forming property] (Film-forming property on glass substrate) Each polyamide composition prepared in the following examples and comparative examples was coated on a glass substrate (trade name: Eagle XG, material: alkali-free glass, thickness: 0.7 mm, size: 100 mm×100 mm) manufactured by Corning Incorporated using a rotary coater, and then heated at 120°C for 30 minutes in air and then at 460°C for 45 minutes in a nitrogen atmosphere to obtain a laminate having a polyimide film with a thickness of 10 μm on the glass substrate. The obtained laminate was visually checked for the presence or absence of ridges between the glass substrate and the polyimide film.

(Film-forming properties on a-Si layer) After depositing an a-Si layer (thickness: 100 nm) on a glass substrate (trade name: Eagle XG, material: alkali-free glass, thickness: 0.7 mm, size: 100 mm×100 mm) manufactured by Corning, each polyamide composition prepared in the following embodiments and comparative examples was coated on the a-Si layer using a spin coater. Subsequently, the substrate coated with the polyamide composition was heated at 120°C in air for 30 minutes, and then heated at 460°C in a nitrogen atmosphere for 45 minutes, to obtain a laminate having an a-Si layer and a polyimide film with a thickness of 10 μm on the glass substrate in sequence. The obtained laminate was visually checked to see if there was any bulge between the a-Si layer and the polyimide film.

(Evaluation criteria for film forming properties) When there is no bulging between the glass substrate and the polyimide film and between the a-Si layer and the polyimide film, it is evaluated that "the occurrence of poor adhesion is suppressed and the film forming properties are better." On the other hand, when at least one of the bulges exists between the glass substrate and the polyimide film and between the a-Si layer and the polyimide film, it is evaluated that "the occurrence of poor adhesion is not suppressed." , poor film-forming properties."

[Peel Strength] The polyimide films of each laminate obtained in the following examples and comparative examples were cut with a slit of 10 mm width using a guillotine according to ASTM D1876-01 standard. The polyimide films were peeled off 50 mm from the glass substrate using a tensile tester ("Strograph VES1D" manufactured by Toyo Seiki Co., Ltd.) at a temperature of 23°C and a humidity of 55%RH, at a tensile speed of 50 mm/min and a peeling angle of 90°. The average peel strength at this time was taken as the peel strength.

<Preparation of polyimide film> Hereinafter, the method of producing the polyimide film (laminated body) of Examples and Comparative Examples will be described. In addition, below, the compounds and reagents are described using the following abbreviations. In addition, the preparation of the polyamide acid composition used in making the polyimide film was carried out under a nitrogen atmosphere. MPA: 3-methoxy-N,N-dimethylpropionamide NBP: 1-butyl-2-pyrrolidinone BPDA: 3,3',4,4'-biphenyltetracarboxylic dianhydride BPAF : 9,9-Bis(3,4-dicarboxyphenyl)dianhydride SFDA: Spiro[11H-Difuro[3,4-b:3',4'-i]𠮿 -11,9'-[9H]fluorine]-1,3,7,9-tetraketonePDA: p-phenylenediamine BAFL: 9,9-bis(4-aminophenyl)fluorinePAM-E: 1, 3-Bis(3-aminopropyl)tetramethyldisiloxane ODA: 4,4'-oxydiphenylamine APS: 3-aminopropyltriethoxysilane APDE: 3-aminopropyldi Ethoxymethylsilane

[Example 1] To a 300 mL glass separable flask equipped with a stirrer equipped with a stainless steel stirring rod and a nitrogen introduction tube, 85.0 g of MPA was added as the organic solvent for polymerization. Then, while stirring the contents of the flask, 4.037 g of PDA was added to the flask and dissolved. Then, after adding 0.171 g of BPAF and 10.792 g of BPDA to the contents of the flask, the contents of the flask were stirred for 6 hours in an environment with a temperature of 25°C. Then, after adding 0.005 g of APS to the contents of the flask, the contents of the flask were further stirred for 6 hours in an environment with a temperature of 25°C, to obtain a polyamic acid composition. The obtained polyamic acid composition was coated on a glass substrate manufactured by Corning Corporation using a spin coater (trade name: Eagle XG, material: alkali-free glass, thickness: 0.7 mm, size: 100 mm × 100 mm) above, after heating at 120°C for 30 minutes in the air, and then heating at 460°C for 45 minutes in a nitrogen atmosphere, a laminate having a polyimide film with a thickness of 10 μm on a glass substrate was obtained (Example 1) laminated body).

[Examples 2 to 21 and Comparative Examples 1 to 7] Except that the acid dianhydride used and its feeding ratio, the diamine used and its feeding ratio, the silane coupling agent used and its addition amount, and the type of solvent are as shown in Tables 1 and 2, the laminates of Examples 2 to 21 and Comparative Examples 1 to 7 are obtained by the same method as Example 1. Furthermore, in Examples 2 to 4, 9 to 14, 17, 19 and 21, and Comparative Examples 1, 3 and 5 to 7, in which no silane coupling agent is used, after all the acid dianhydride is added to the flask, the contents of the flask are stirred for 6 hours at a temperature of 25°C to obtain a polyamide composition. In addition, regarding any one of Examples 2 to 21 and Comparative Examples 1 to 7, the total mass of the acid dianhydride when preparing the polyamide composition is the same as that of Example 1. In addition, regarding any one of Examples 2 to 21 and Comparative Examples 1 to 7, the total mass of the diamine when preparing the polyamide composition is the same as that of Example 1.

Regarding Examples 1 to 21 and Comparative Examples 1 to 7, the acid dianhydride, diamine, silane coupling agent and solvent used, as well as the internal stress, TD1, film forming properties and peel strength are shown in Table 1 and Table 2. In addition, in Table 1 and Table 2, "-" in the columns of acid dianhydride, diamine and silane coupling agent means that these components are not used. In addition, in Table 1 and Table 2, "-" in the column of peel strength means that the peel strength was not measured.

In addition, in Tables 1 and 2, the numerical value in the column "Acid dianhydride" is the content rate (unit: mole %) of each acid dianhydride relative to the total amount of diamine used (100 mole %). In addition, in Table 1 and Table 2, the numerical value in the "diamine" column is the content rate (unit: mole %) of each diamine relative to the total amount of the diamine used (100 mole %). In addition, in Table 1 and Table 2, the numerical value in the "silane coupling agent" column is the amount of the silane coupling agent added relative to 100 parts by weight of polyamide (unit: parts by weight). Furthermore, regarding any one of Examples 1 to 21 and Comparative Examples 1 to 7, the molar fraction of each residue of the polyamic acid in the prepared polyamic acid composition is equal to that of the polyamic acid. The molar fractions of each monomer (diamine and tetracarboxylic dianhydride) used in the synthesis are consistent.

[Table 1] Acid dianhydride [mol%] Diamine [mol%] Silane coupling agent [parts by weight] Solvent Internal stress [MPa] TD1[℃] Film-forming properties (presence or absence of ridges) Peel strength [N/cm] BPDA BPAF SFDA PDAs BAFL PAM-E ODA APS APDE Glass base board a-Si layer Example 1 98.5 1 - 100 - - - 0.05 - MPA 8 568 without without - Example 2 98.5 1 - 99.8 - 0.2 - - - MPA 5 569 without without - Example 3 98.5 1 - 99.7 - 0.3 - - - MPA 5 569 without without - Example 4 94.5 5 - 100 - - - - - MPA 9 562 without without - Example 5 98.5 - 1 100 - - - 0.05 - MPA 7 573 without without - Example 6 98.5 - 1 100 - - - 0.1 - MPA 8 572 without without - Example 7 98.5 - 1 100 - - - - 0.05 MPA 4 574 without without - Example 8 98.5 - 1 100 - - - - 0.1 MPA 4 573 without without - Example 9 98.5 - 1 99.7 - 0.3 - - - MPA 4 574 without without - Example 10 98.5 - 1 99.7 - 0.3 - - - NBP 2 562 without without - Example 11 96.5 - 3 100 - - - - - MPA 5 570 without without 0.20 Example 12 96.5 - 3 99.8 - 0.2 - - - MPA 4 569 without without 0.49 Example 13 96.5 - 3 99.7 - 0.3 - - - MPA 3 569 without without 0.52 Example 14 96.5 - 3 99.4 - 0.6 - - - MPA 4 565 without without 0.61 Example 15 96.5 - 3 100 - - - 0.2 - MPA 4 567 without without 1.79 Example 16 96.5 - 3 100 - - - - 0.2 MPA 1 568 without without 0.77

[Table 2] Acid dianhydride [mol%] Diamine [mol%] Silane coupling agent [parts by weight] Solvent Internal stress [MPa] TD1[℃] Film-forming properties (presence or absence of ridges) Peel strength [N/cm] BPDA BPAF SFDA PDAs BAFL PAM-E ODA APS APDE Glass base board a-Si layer Example 17 95 - 4.5 100 - - - - - MPA 5 568 without without - Example 18 95 - 4.5 100 - - - 0.05 - MPA 8 569 without without - Example 19 95 - 4.5 100 - - - - - NBP 4 554 without without - Example 20 99.5 - - 99 1 - - 0.05 - MPA 9 567 without without - Example 21 99.5 - - 98.7 1 0.3 - - - MPA 6 568 without without - Comparative example 1 99.5 - - 100 - - - - - MPA 6 572 have have - Comparative example 2 99.5 - - 100 - - - 0.05 - MPA 10 570 have have - Comparative example 3 99.5 - - 100 - - - - - NBP 2 560 have have - Comparative example 4 99.5 - - 100 - - - 0.05 - NBP 2 558 have have - Comparative example 5 99.5 - - 90 - - 10 - - MPA 10 570 have have - Comparative example 6 99.5 - - 70 - - 30 - - MPA twenty three 568 have have - Comparative example 7 99.5 - - 50 - - 50 - - MPA 35 564 without without -

The polyamic acid in the polyamic acid composition used in Examples 1 to 21 has residue (1), a BPDA residue and a PDA residue. The polyamide composition used in Examples 1 to 21 contains a specific organic solvent.

As shown in Tables 1 and 2, in Examples 1 to 21, the internal stress is 30 MPa or less. Therefore, in Examples 1 to 21, the internal stress can be reduced. In Examples 1 to 21, there is no bulge between the glass substrate and the polyimide film, and between the a-Si layer and the polyimide film. Therefore, in Examples 1 to 21, the occurrence of poor adhesion is suppressed, and the film forming property is good.

The polyamic acid in the polyamic acid composition used in Comparative Examples 1 to 7 has a BPDA residue and a PDA residue, but does not have the residue (1). The polyamide composition used in Comparative Examples 1 to 7 contains a specific organic solvent.

As shown in Table 2, in Comparative Examples 1 to 6, there were ridges both between the glass substrate and the polyimide film and between the a-Si layer and the polyimide film. Therefore, in Comparative Examples 1 to 6, the occurrence of poor adhesion was not suppressed, and the film forming properties were poor. In Comparative Example 7, the internal stress exceeded 30 MPa. Therefore, in Comparative Example 7, the internal stress cannot be reduced.

The above results show that according to the present invention, a safer solvent can be used and the occurrence of poor adhesion can be suppressed, and internal stress can be reduced.

Claims (10)

A polyamine composition comprising polyamine and an organic solvent, wherein the polyamine has a residue comprising a divalent organic group represented by the following chemical formula (1), a 3,3',4,4'-biphenyltetracarboxylic dianhydride residue, and a p-phenylenediamine residue, and the organic solvent comprises one or more compounds selected from the group consisting of compounds represented by the following general formula (2) and compounds represented by the following general formula (3), [Chemical 1] (In the above general formula (2), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a monovalent organic group having 1 or more carbon atoms, at least one of R ¹ , R ² and R ³ represents a monovalent organic group having 2 or more carbon atoms, and in the above general formula (3), R ⁴ represents a monovalent organic group having 2 or more carbon atoms). The polyamine composition of claim 1, wherein the residue of the divalent organic group represented by the above chemical formula (1) is selected from the group consisting of a tetravalent organic group represented by the following chemical formula (4), a tetravalent organic group represented by the following chemical formula (5), and a divalent organic group represented by the following chemical formula (6), [Chemical 2] . The polyamic acid composition of claim 1, wherein the content rate of the residues containing the divalent organic group represented by the above chemical formula (1) is relative to all the tetracarboxylic dianhydride residues constituting the above polyamic acid and The total 100 mol% of all diamine residues constituting the polyamide acid is 15 mol% or less. The polyamine composition of claim 1, wherein the organic solvent is 3-methoxy-N,N-dimethylpropionamide, 3-butoxy-N,N-dimethylpropionamide or 1-butyl-2-pyrrolidone. The polyamic acid composition of claim 1, wherein the polyamic acid further has a 1,3-bis(3-aminopropyl)tetramethyldisiloxane residue. The polyamic acid composition of claim 5, wherein the content of the 1,3-bis(3-aminopropyl)tetramethyldisiloxane residue is relative to the diamine constituting the polyamic acid. The total amount of residues is 0.1 mol% or more and 1.0 mol% or less. The polyamic acid composition of claim 1, further comprising a silane coupling agent. A method for producing polyimide comprises heating the polyamic acid composition as claimed in claim 1 to imidize the polyamic acid. A method for manufacturing a laminate, the laminate having a support and a polyimide film, and the manufacturing method comprises coating the polyimide composition as claimed in claim 1 on a support to form a coating film containing the polyimide, and heating the coating film to imidize the polyimide. A method for manufacturing an electronic device, comprising: Step Sa, which is to heat the polyamide composition as in claim 1 to imidize the polyamide; and Step Sb, which is to configure an electronic component on the polyimide film obtained by the above step Sa.