TW202006028A - Polyimide film, polyimide material, laminate, member for display, member for touch panel, liquid crystal display device, and organic electroluminescence display device - Google Patents

Abstract

Provided is a film with excellent transparency and better flex resistance. Disclosed is a polyimide film comprising a polyimide having a structure represented by the following general formula (1); wherein, as residual solvents in the film, a content of an organic solvent that has a boiling point of less than 100 DEG C at 1 atm, is 2000 ppm or less, and a content of an organic solvent that has a boiling point of 100 DEG C or more at 1 atm, is 100 ppm or less; and a total light transmittance measured in accordance with JIS K7361-1 is 85% or more: General Formula (1) (reference characters in the formula are as described in the Specification.).

Description

Polyimide film, polyimide material, laminate, display member, touch panel member, liquid crystal display device, and organic electroluminescence display device

The invention relates to a polyimide film, a polyimide material, a laminate, a display member, a touch panel member, a liquid crystal display device, and an organic electroluminescence display device.

The thinner plate glass is excellent in hardness and heat resistance, but on the other hand, it is difficult to bend and easily breaks when dropped. There is a problem in workability, and it has the disadvantages of being heavier than plastic products. Therefore, in recent years, from the viewpoint of workability and weight reduction, resin products such as resin substrates and resin films have gradually replaced glass products, and resin products that have become glass substitute products are constantly being studied.

For example, with the rapid advancement of displays such as liquid crystals, organic ELs, and electronic devices such as touch panels, thinning or lightening of devices is required, and further flexibility is required. These devices were previously formed with various electronic components such as thin transistors or transparent electrodes on a thinner plate glass. By changing the thinner plate glass to a resin film, the impact resistance of the panel itself can be enhanced, Flexible, thinner or lighter.

Generally, polyimide is a highly heat-resistant resin obtained by subjecting a polyamic acid obtained by a condensation reaction of an aromatic tetracarboxylic anhydride and an aromatic diamine to a dehydration ring-closure reaction. However, polyimide usually exhibits yellow or brown coloration, and therefore, it is difficult to use in fields requiring transparency such as display applications or optical applications. Therefore, the industry is investigating the application of polyimide with improved transparency to display components. For example, in Patent Document 1, as a polyimide resin having high heat resistance, high transparency, and low water absorption, it is disclosed that a polyimide resin selected from 1,2,4,5-cyclohexanetetracarboxylic acid, 1,2, 4,5-cyclohexanetetracarboxylic dianhydride and at least one compound containing an aryl group in the group consisting of reactive derivatives and selected from a specific formula having at least one phenylene group and isocyanide Polyimide obtained by reacting at least one imine group-forming compound of a propyl compound is described as a substrate material suitable for flat panel displays or mobile phone devices.

Furthermore, Patent Document 2 discloses a transparent polyimide film containing structural units derived from aromatic dianhydride and aromatic diamine, and further containing additives for improving tear strength, or derived from The structural unit of the monomer of the functional group in the group consisting of hexafluoro group, sulfone group and oxy group.

In addition, in Patent Document 3, in order to obtain a colorless and transparent polyimide film with low residual stress generated from an inorganic film and excellent mechanical and thermal properties as a substrate for a flexible device substrate The imine film reveals a polyimide precursor that uses a specific fluorine-based aromatic diamine and a polysiloxane compound having a siloxane skeleton with a silicon atom number of 3 to 200 as the monomer component Polyimide film obtained by amination. In Patent Document 3, it is described that a polyimide film with an inorganic film (SiN film) is formed using the above polyimide precursor. As a result, after the bending test of repeated bending 10 times, neither a crack nor a crack was observed. No peeling (〇) was observed, or cracking (△) was observed.

In addition, in Patent Document 4, as a polyimide having a low refractive index and high folding resistance, polysilicon dioxide having a silicon atom number of 2 to 21 containing 10% by weight or more of the weight of the diamine raw material is described. amine.

Furthermore, in Patent Document 5, the inventors et al. disclosed a polyimide film as a resin film that improves bending resistance and suppresses the decrease in surface hardness, and contains 10 moles including the total amount of diamine residues. Polyimide with a diamine residue of 1 or 2 silicon atoms in the main chain of more than 50% and less than 50 mole %, and has a specific total light transmittance, a specific yellowness, and a specific glass transfer Temperature, and specific tensile modulus of elasticity. Prior technical literature Patent Literature

Patent Document 1: Japanese Patent Laid-Open No. 2006-199945 Patent Document 2: Japanese Special Publication No. 2014-501301 Patent Document 3: International Publication No. 2014/098235 Patent Document 4: Japanese Patent Publication No. 2008-64905 Patent Literature 5: Japanese Patent Publication No. 2018-28073

[Problems to be solved by the invention]

The industry first requires excellent transparency for resin products that become glass substitutes. The mobile device with a foldable screen is in a folded state when being transported, and in a folded and unfolded state when in use. Therefore, a flexible display mounted on a mobile device is required to have no display failure even if it is repeatedly bent, and a substrate or surface material for a flexible display is required to have bending resistance during repeated bending (hereinafter sometimes referred to as dynamic resistance) Flexibility). Furthermore, most mobile devices with foldable screens are transported in a folded state. Therefore, the flexible display mounted on the mobile device is required to be restored to its original state when it returns to flat even if it is bent for a long time. The base material or surface material for a sex display also requires recovery after being bent for a long time (hereinafter sometimes referred to as static bending resistance). However, the polyimide film having transparency of the prior art is required to have further improved bending resistance.

The present invention has been completed in view of the above problems, and its main object is to provide a polyimide film having excellent transparency and improved bending resistance. In addition, an object of the present invention is to provide a polyimide material for manufacturing the polyimide film, a laminate having the polyimide film, and a display that is the polyimide film or the laminate A member, and a touch panel member provided with the polyimide film or the laminate, the liquid crystal display device, and the organic electroluminescence display device. [Technical means to solve the problem]

The polyimide film of the present invention contains a polyimide having a structure represented by the following general formula (1), As the residual solvent in the membrane, the content of the organic solvent with a boiling point of not more than 100°C at 1 atmosphere is 2000 ppm or less, and the content of the organic solvent with a boiling point of 100°C or more at 1 atmosphere is 100 ppm or less, The total light transmittance measured according to JIS K7361-1 is above 85%.

（通式（1）中，R¹ 表示作為具有芳香族環或脂肪族環之四羧酸殘基之四價基，R² 表示作為二胺殘基之二價基，R² 總量之2.5莫耳%以上且50莫耳%以下為於主鏈具有矽原子之二胺殘基，50莫耳%以上且97.5莫耳%以下為不具有矽原子且具有芳香族環或脂肪族環之二胺殘基；n表示重複單位數）General formula (1)

(In general formula (1), R ¹ represents a tetravalent group as a tetracarboxylic acid residue having an aromatic ring or an aliphatic ring, R ² represents a divalent group as a diamine residue, and 2.5 of the total amount of R ² Molar% or more and 50 mol% or less are diamine residues having a silicon atom in the main chain, 50 mol% or more and 97.5 mol% or less are the two having no silicon atom and having an aromatic ring or an aliphatic ring Amine residues; n represents the number of repeating units)

In terms of excellent surface hardness, the polyimide film of the present invention preferably has a tensile speed of 10 mm/min and a distance between chucks of 20 mm/40 mm for a 15 mm×40 mm test piece in accordance with JIS K7127. The tensile elastic modulus measured by mm at 25°C is above 1.8 GPa.

In terms of excellent transparency, the polyimide film of the present invention preferably has a value of 0.10 or less obtained by dividing the yellowness calculated by JIS K7373-2006 by the film thickness (μm).

In terms of light transmittance, bending resistance, and surface hardness, the polyimide film of the present invention is preferably in the polyimide having the structure represented by the above general formula (1), and the above general formula ( 1) R ^{1 in} is selected from the group consisting of cyclohexane tetracarboxylic dianhydride residues, cyclopentane tetracarboxylic dianhydride residues, and dicyclohexane-3,4,3',4'-tetracarboxylic diacid Anhydride residues, cyclobutane tetracarboxylic dianhydride residues, pyromellitic dianhydride residues, 3,3',4,4'-biphenyltetracarboxylic dianhydride residues, 2,2',3 ,3'-Biphenyltetracarboxylic dianhydride residue, 4,4'-(hexafluoroisopropylidene) diphthalic anhydride residue, 3,4'-(hexafluoroisopropylidene) di Phthalic anhydride residues, 3,3'-(hexafluoroisopropylidene) diphthalic anhydride residues, 4,4'-oxydiphthalic anhydride residues, and 3,4' -At least one tetravalent group in the group consisting of oxydiphthalic anhydride residues.

In the polyimide film of the present invention, in terms of light transmittance, bending resistance and surface hardness, it is preferably in the polyimide having the structure represented by the general formula (1), the above The above-mentioned diamine residue having no silicon atom and having an aromatic ring or an aliphatic ring in R ² in the general formula (1) is selected from the group consisting of trans-cyclohexanediamine residue and trans-1,4-bis Methylenecyclohexanediamine residue, 4,4'-diaminodiphenyl sulfone residue, 3,4'-diaminodiphenyl sulfide residue, 2,2-bis(4-amino group Phenyl)propane residue, 3,3'-bis(trifluoromethyl)-4,4'-((1,1,1,3,3,3-hexafluoropropane-2,2-diyl) Bis(4,1-phenoxy)]diphenylamine residue, 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3,3- Hexafluoropropane residue, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane residue, and the following general formula (2) At least one kind of divalent group in the group formed by the divalent groups represented.

（通式（2）中，R³ 及R⁴ 分別獨立表示氫原子、烷基、或全氟烷基)General formula (2)

(In the general formula (2), R ³ and R ⁴ independently represent a hydrogen atom, an alkyl group, or a perfluoroalkyl group)

In terms of improving bending resistance and surface hardness, the polyimide film of the present invention is preferably in a polyimide having the structure represented by the above general formula (1), and R ² represents A diamine residue having a silicon atom, and a divalent group having at least one diamine residue having 1 or 2 silicon atoms in the main chain, the total amount of R ² is 2.5 mol% or more and 50 mol% or less For a diamine residue having 1 or 2 silicon atoms in the main chain, 50 mol% or more and 97.5 mol% or less are diamine residues having no silicon atom and having an aromatic ring or an aliphatic ring.

Furthermore, the present invention provides a polyimide material which is the polyimide material for manufacturing the polyimide film of the present invention described above, and With the structure represented by the above general formula (1), as the residual solvent, the content of the organic solvent having a boiling point of not more than 100°C at 1 atmosphere is 2000 ppm or less, and the content of the organic solvent having a boiling point of 100°C or more at 1 atmosphere is 100 Below ppm.

In addition, the present invention provides a laminate including the above-described polyimide film of the present invention and a hard coat layer containing at least one polymer of a radically polymerizable compound and a cationic polymerizable compound.

Furthermore, the present invention provides a member for a display, which is the polyimide film of the present invention described above or the laminate of the present invention described above. This display member can be used for a flexible display.

In addition, the present invention provides a touch panel member having: the polyimide film of the present invention described above or the laminate of the present invention described above; A transparent electrode, which is arranged on one side of the polyimide film or the laminate, and is composed of a plurality of conductive parts; and A plurality of lead wires are electrically connected to at least one side of the end of the conductive portion.

Furthermore, the present invention provides a liquid crystal display device comprising: the polyimide film of the present invention described above or the laminate of the present invention described above; and A liquid crystal display unit disposed on one surface side of the polyimide film or the laminate, and having a liquid crystal layer between opposing substrates.

Furthermore, the present invention provides an organic electroluminescence display device comprising the polyimide film of the present invention or the laminate of the present invention, and An organic electroluminescence display portion, which is disposed on one side of the polyimide film or the laminate, and has an organic electroluminescence layer between opposing substrates. [Effect of invention]

According to the present invention, a polyimide film having excellent transparency and improved bending resistance can be provided. In addition, the present invention can provide a polyimide material for manufacturing the polyimide film, a laminate having the polyimide, a display member that is the polyimide film or the laminate, and A touch panel member, a liquid crystal display device, and an organic electroluminescence display device provided with the polyimide film or the laminate.

Hereinafter, the polyimide film of the present invention, a polyimide material for manufacturing the polyimide film, a laminate using the polyimide film, a display member, a touch panel member, a liquid crystal display device, And the organic electroluminescence display device will be described in detail. In addition, the shape or geometric conditions used in this specification and the terms such as "parallel", "orthogonal", and "identical" or the values of lengths and angles that specify these degrees are not restricted to strict The meaning of this is explained within the scope that can expect the same function. In this specification, (meth)acrylic means acrylic and methacrylic. In addition, in this specification, "light" means active light or radiation, and includes, for example, the bright line spectrum of a mercury lamp, far ultraviolet, extreme ultraviolet (EUV), X-ray, and electron beam represented by an excimer laser. In addition, in the drawings attached to this specification, in order to make illustrations and understanding easier, the scale and aspect ratio may be appropriately changed from the real thing to exaggerate the performance. In addition, in this specification, "ppm" used as the unit of the content of the organic solvent in a polyimide film means mass ppm.

1. Polyimide film The polyimide film of the present invention contains a polyimide having a structure represented by the following general formula (1), As the residual solvent in the membrane, the content of the organic solvent with a boiling point of not more than 100°C at 1 atmosphere is 2000 ppm or less, and the content of the organic solvent with a boiling point of 100°C or more at 1 atmosphere is 100 ppm or less, The total light transmittance measured according to JIS K7361-1 is above 85%.

（通式（1）中，R¹ 表示作為具有芳香族環或脂肪族環之四羧酸殘基之四價基，R² 表示作為二胺殘基之二價基，R² 總量之2.5莫耳%以上且50莫耳%以下為於主鏈具有矽原子之二胺殘基，50莫耳%以上且97.5莫耳%以下為不具有矽原子且具有芳香族環或脂肪族環之二胺殘基；n表示重複單位數）General formula (1)

(In general formula (1), R ¹ represents a tetravalent group as a tetracarboxylic acid residue having an aromatic ring or an aliphatic ring, R ² represents a divalent group as a diamine residue, and 2.5 of the total amount of R ² Molar% or more and 50 mol% or less are diamine residues having a silicon atom in the main chain, 50 mol% or more and 97.5 mol% or less are the two having no silicon atom and having an aromatic ring or an aliphatic ring Amine residues; n represents the number of repeating units)

According to the present invention, by making the following polyimide film, it is possible to provide a polyimide film having excellent transparency and improved bending resistance. The polyimide film is a polymer contained in the polyimide film. Acetyleneimine has a specific structure that contains a tetracarboxylic acid residue having an aromatic ring or an aliphatic ring as a diamine residue, including 2.5 mol% or more and 50 mol% or less in the main chain Diamine residues of silicon atoms, and containing 50 mol% or more and 97.5 mol% or less of diamine residues without silicon atoms and having aromatic or aliphatic rings; as residual solvent in the membrane, replace 1 The content of the organic solvent with a boiling point of less than 100°C under atmospheric pressure is set to 2000 ppm or less, and the content of the organic solvent with a boiling point of 100°C or higher at 1 atmosphere is set to 100 ppm or less, and has the specific full light transmittance described above.

As also described in Patent Document 5, the present inventors have disclosed that if a diamine residue having 1 or 2 silicon atoms in the main chain is contained at an appropriate ratio in the total amount of diamine residues, it is resistant to bending Sex becomes good. In addition, as described in Patent Document 4, it is described that a polyimide film containing 10% by weight or more of the weight of the diamine raw material and a polysiloxane diamine having 2 to 21 silicon atoms has high folding endurance. However, it is known that even if the structure of the polyimide constituting the polyimide film is the same, the bending resistance will change depending on the manufacturing method of the polyimide film.

The inventors of the present invention have found that by containing the diamine residues having silicon atoms in the main chain of the polyimide film at a proper ratio in the total amount of diamine residues, 1 of the residual solvents in the film The boiling point of the atmospheric pressure (hereinafter, sometimes referred to as "boiling point" in this specification) The content of the organic solvent that does not reach 100°C is set to 2000 ppm or less, and the content of the organic solvent with a boiling point of 1 atmosphere is 100°C or more It is 100 ppm or less, and the bending resistance of the above-mentioned polyimide film is improved. Since the residual solvent is a solvent used for manufacturing the polyimide film, it is basically a good solvent for the polyimide film. It is inferred that if the organic solvent with a boiling point above 100°C exceeds 100 ppm based on the amount of residual solvent in the film, it is suspected that part of the polyimide constituting the film will be dissolved in the residual solvent, and the film is easily damaged due to dynamic bending Easy to break. On the other hand, although the reason is not clear, organic solvents with a boiling point of less than 100°C are less likely to affect the dynamic bending resistance of the film than organic solvents with a boiling point of 100°C or higher, and allow more residual amounts. Organic solvents with a boiling point of less than 100°C are more likely to affect the static bending resistance of the membrane than organic solvents with a boiling point of 100°C or higher. It is inferred whether the reason is that if more organic solvent with a boiling point of less than 100°C remains in the film, part of the organic solvent with a boiling point of less than 100°C volatilizes when the film is bent for a long time, resulting in the film One part shrinks, and it is not easy to recover when it returns to flat. In the present invention, it is inferred that the content of the residual solvent in the polyimide film is set to an organic solvent having a boiling point of less than 100°C and an organic solvent having a boiling point of 100°C or more, respectively, at a specific content ratio or less, so A polyimide film is obtained which is not easily damaged during dynamic bending and easily recovers during static bending.

Furthermore, in the following examples and comparative examples, it is revealed that even in the case of manufacturing a polyimide film using a polyimide precursor having the same molecular structure, if the preparation method of polyimide or polyimide When the manufacturing method of the amine film is different and the state of the film is different, the amount of residual solvent changes and the bending resistance changes. This indicates that the bending resistance of the polyimide film does not depend only on the chemical structure of the polyimide, and the amount of residual solvent indicates the state of the polyimide film related to the bending resistance. Furthermore, by making a polyimide film having the above-mentioned specific full light transmittance, a polyimide film having excellent transparency and improved bending resistance can be provided.

Hereinafter, the polyimide film of the present invention will be described in detail. The polyimide film of the present invention contains polyimide and has the above-mentioned specific characteristics. As long as the effect of the present invention is not impaired, it may further contain other components or may have other configurations. 1. Polyimide The polyimide system is obtained by reacting a tetracarboxylic acid component and a diamine component. It is preferable to obtain the polyimidic acid by polymerization of the tetracarboxylic acid component and the diamine component and perform the imidate. Acetylimidization can be carried out by thermal imidization or chemical imidization. In addition, it can also be produced by a method using a combination of thermal imidization and chemical imidization. The polyimide used in the present invention contains a polyimide having a structure represented by the following general formula (1).

（通式（1）中，R¹ 表示作為具有芳香族環或脂肪族環之四羧酸殘基之四價基，R² 表示作為二胺殘基之二價基，R² 總量之2.5莫耳%以上且50莫耳%以下為於主鏈具有矽原子之二胺殘基，50莫耳%以上且97.5莫耳%以下為不具有矽原子且具有芳香族環或脂肪族環之二胺殘基；n表示重複單位數）General formula (1)

(In general formula (1), R ¹ represents a tetravalent group as a tetracarboxylic acid residue having an aromatic ring or an aliphatic ring, R ² represents a divalent group as a diamine residue, and 2.5 of the total amount of R ² Molar% or more and 50 mol% or less are diamine residues having a silicon atom in the main chain, 50 mol% or more and 97.5 mol% or less are the two having no silicon atom and having an aromatic ring or an aliphatic ring Amine residues; n represents the number of repeating units)

Here, the term "tetracarboxylic acid residue" refers to a residue obtained by removing four carboxyl groups from tetracarboxylic acid, and represents the same structure as the residue obtained by removing the acid dianhydride structure from tetracarboxylic dianhydride. The diamine residue refers to a residue obtained by removing two amine groups from the diamine.

The tetracarboxylic acid residue in R ¹ of the general formula (1) may be a residue obtained by removing an acid dianhydride structure from a tetracarboxylic dianhydride having an aromatic ring, or a tetracarboxylic acid having an aliphatic ring The residue of the dianhydride after removing the structure of the acid dianhydride. Examples of the tetracarboxylic dianhydride having an aromatic ring include pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 2,2',3, 3'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 2 ,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2,3-dicarboxyphenyl) propane dianhydride, bis(3,4-dicarboxyphenyl) ether di Anhydride, bis(3,4-dicarboxyphenyl) dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, bis(2,3-dicarboxyphenyl)methanedi Anhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)-1,1,1,3,3,3-hexafluoropropane dianhydride , 2,2-bis(2,3-dicarboxyphenyl)-1,1,1,3,3,3-hexafluoropropane dianhydride, 1,3-bis[(3,4-dicarboxy)benzene Formyl]phthalic anhydride, 1,4-bis[(3,4-dicarboxy)benzoyl]phthalic anhydride, 2,2-bis{4-[4-(1,2-dicarboxy) Phenoxy]phenyl}propane dianhydride, 2,2-bis{4-[3-(1,2-dicarboxy)phenoxy]phenyl}propane dianhydride, bis{4-[4-(1 ,2-dicarboxy)phenoxy]phenyl}ketone dianhydride, bis{4-[3-(1,2-dicarboxy)phenoxy]phenyl}ketone dianhydride, 4,4'-bis[ 4-(1,2-dicarboxy)phenoxy]biphenyl dianhydride, 4,4'-bis[3-(1,2-dicarboxy)phenoxy]biphenyl dianhydride, bis{4-[ 4-(1,2-dicarboxy)phenoxy]phenyl}ketone dianhydride, bis{4-[3-(1,2-dicarboxy)phenoxy]phenyl}ketone dianhydride, bis{4 -[4-(1,2-dicarboxy)phenoxy]phenyl}suan dianhydride, bis{4-[3-(1,2-dicarboxy)phenoxy]phenyl}suan dianhydride, bis {4-[4-(1,2-dicarboxy)phenoxy]phenyl}sulfide dianhydride, bis{4-[3-(1,2-dicarboxy)phenoxy]phenyl}sulfide Dianhydride, 4,4'-(hexafluoroisopropylidene) diphthalic anhydride, 3,4'-(hexafluoroisopropylidene) diphthalic anhydride, 3,3'-(hexa (Fluoroisopropylidene) diphthalic anhydride, 4,4'-oxydiphthalic anhydride, 3,4'-oxydiphthalic anhydride, 2,3,6,7-naphthalenetetracarboxylic acid Acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,2,3,4-benzenetetracarboxylic dianhydride, 3 ,4,9,10-Perylenetetracarboxylic dianhydride, 2,3,6,7-anthracenetetracarboxylic dianhydride, 1,2,7,8-phenanthrenetetracarboxylic dianhydride, etc. Examples of the tetracarboxylic dianhydride having an aliphatic ring include cyclohexane tetracarboxylic dianhydride, cyclopentane tetracarboxylic dianhydride, and dicyclohexane-3,4,3',4'-tetra Carboxylic dianhydride, cyclobutane tetracarboxylic dianhydride, etc. These can be used alone or in combination of two or more.

The diamine residue having a silicon atom in the main chain in R ² of the above general formula (1) may be a residue obtained by removing two amine groups from the diamine having a silicon atom in the main chain. The polyimide film used in the present invention can be improved as described above by introducing a specific amount of a soft molecular skeleton having a silicon atom in the main chain between molecular skeletons containing an aromatic ring or an aliphatic ring as a main component Bending resistance. In addition, when a functional layer such as the following hard coat layer is laminated, the adhesion to the functional layer such as a hard coat layer can be improved.

The diamine residue having a silicon atom in the main chain can be set as the residue after removing two amine groups from the diamine having a silicon atom in the main chain. Examples of the diamine residue having a silicon atom in the main chain include the diamine represented by the following general formula (A).

（通式（A）中，L分別獨立為直接鍵或-O-鍵，R¹⁰ 分別獨立表示可具有取代基、可含有氧原子或氮原子之碳數1以上且20以下之一價烴基；R¹¹ 分別獨立表示可具有取代基、可含有氧原子或氮原子之碳數1以上且20以下之二價烴基；k為0〜200之數；具有複數個之L、R¹⁰ 及R¹¹ 可分別相同亦可不同）General formula (A)

(In the general formula (A), L is independently a direct bond or -O- bond, and R ¹⁰ independently represents a monovalent hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, may contain an oxygen atom or a nitrogen atom; R ¹¹ independently represents a divalent hydrocarbon group having a carbon number of 1 or more and 20 or less, which may have a substituent, may contain an oxygen atom or a nitrogen atom; k is a number from 0 to 200; having a plurality of L, R ¹⁰ and R ¹¹ may The same or different)

Examples of the monovalent hydrocarbon group represented by R ¹⁰ include alkyl groups having 1 to 20 carbon atoms, aryl groups, and combinations thereof. The alkyl group may be any of linear, branched, or cyclic, and may be a combination of linear or branched and cyclic. The alkyl group having a carbon number of 1 or more and 20 or less is preferably an alkyl group having a carbon number of 1 or more and 10 or less, and specific examples include methyl, ethyl, propyl, isopropyl, butyl, and iso Butyl, tertiary butyl, pentyl, hexyl, etc. The cyclic alkyl group is preferably a cycloalkyl group having a carbon number of 3 or more and 10 or less. Specific examples thereof include cyclopentyl and cyclohexyl. The aryl group is preferably an aryl group having 6 or more carbon atoms and 12 or less. Specific examples thereof include a phenyl group, a tolyl group, and a naphthyl group. In addition, the monovalent hydrocarbon group represented by R ¹⁰ may be an aralkyl group, and examples thereof include benzyl, phenylethyl, and phenylpropyl. Examples of the hydrocarbon group that may contain an oxygen atom or a nitrogen atom include an ether bond, a carbonyl bond, an ester bond, an amide bond, and an imino bond (-NH-) using the following divalent hydrocarbon group and the above-mentioned monovalent hydrocarbon group A base formed by bonding at least one of them. The substituent that the monovalent hydrocarbon group represented by R ¹⁰ may have is not particularly limited as long as the effect of the present invention is not impaired, and examples include halogen atoms such as fluorine atoms and chlorine atoms, and hydroxyl groups.

The monovalent hydrocarbon group represented by R ¹⁰ is preferably an alkyl group having a carbon number of 1 or more and 3 or less, or a carbon number of 6 or more and 10 or less in terms of both the improvement of bending resistance and the surface hardness. The aryl group is more preferably an alkyl group having 1 to 3 carbon atoms. The alkyl group having 1 to 3 carbon atoms is more preferably a methyl group, and the aryl group having 6 to 10 carbon atoms is more preferably a phenyl group.

Examples of the divalent hydrocarbon group represented by R ^{1 1} include alkylene groups having 1 to 20 carbon atoms, aryl groups, and combinations of these. The alkylene group may be linear, branched, or cyclic, or may be a combination of linear or branched and cyclic. The alkylene group having 1 to 20 carbon atoms is preferably an alkylene group having 1 to 10 carbon atoms, and examples thereof include methylene, ethyl, various propyl, various butyl, and alkylene groups. A group such as a combination of linear or branched alkylene and cyclic alkylene such as cyclohexyl. The arylene group is preferably a aryl group having 6 or more carbon atoms and 12 or less. Examples of the aryl group include phenylene group, biphenylene group, and naphthyl group, and may further have the following Substituents of the family ring. Examples of the divalent hydrocarbon group which may contain an oxygen atom or a nitrogen atom include at least one of the above-mentioned divalent hydrocarbon groups using at least one of an ether bond, a carbonyl bond, an ester bond, an amide bond, and an imino bond (-NH-). The foundation of the knot. The substituent that the divalent hydrocarbon group represented by R ¹¹ may have may be the same as the substituent that the monovalent hydrocarbon group represented by R ¹⁰ may have.

The divalent hydrocarbon group represented by R ¹¹ is preferably an alkylene group having a carbon number of 1 or more and 6 or less, or a carbon number of 6 or more and 10 or less, in terms of improvement in bending resistance and surface hardness. The alkylene group is more preferably an alkylene group having 2 to 4 carbon atoms, and the alkylene group is preferably linear or branched.

k is a number from 0 to 200. In terms of both the improvement of bending resistance and the surface hardness, the average value of k is preferably 0 or more and 6 or less, and preferably 0 or more and 4 or less. Among them, k is preferably 0 or 1.

As the above-mentioned diamine residue having a silicon atom in the main chain of R ² , it is preferable to have one or more in the main chain in terms of excellent bending resistance and excellent compatibility with surface hardness. 2 diamine residues of silicon atoms.

Examples of the diamine having one silicon atom in the main chain include the diamine represented by the following general formula (A-1) of the diamine represented by the above general formula (A) and k=0. In addition, as the diamine having two silicon atoms in the main chain, for example, the diamine represented by the following general formula (A-2) in which k=1 of the diamines represented by the general formula (A) can be cited.

通式（A-2）

（通式（A-1）及通式（A-2）中，L分別獨立為直接鍵或-O-鍵，R¹⁰ 分別獨立表示可具有取代基、亦可含有氧原子或氮原子之碳數1以上且20以下之一價烴基；R¹¹ 分別獨立表示可具有取代基、可含有氧原子或氮原子之碳數1以上且20以下之二價烴基；具有複數個之L、R¹⁰ 及R¹¹ 可分別相同亦可不同）General formula (A-1)

General formula (A-2)

(In general formula (A-1) and general formula (A-2), L is independently a direct bond or -O- bond, and R ¹⁰ independently represents a carbon that may have a substituent, and may also contain an oxygen atom or a nitrogen atom A monovalent hydrocarbon group of 1 or more and 20 or less; R ¹¹ independently represents a divalent hydrocarbon group of 1 or more and 20 or less carbons which may have a substituent, and may contain an oxygen atom or a nitrogen atom; having a plurality of L, R ¹⁰ and R ¹¹ may be the same or different)

The molecular weight of the diamine residue having a silicon atom in the main chain is preferably 3,000 or less, preferably 2,000 or less, preferably in terms of suppressing molecular mobility, imparting bending resistance, and giving consideration to surface hardness. It is 1000 or less, more preferably 800 or less, and even more preferably 500 or less, particularly preferably 300 or less. Furthermore, the molecular weight of the diamine residue having 1 or 2 silicon atoms in the main chain is preferably 1,000 or less, more preferably 800 or less, still more preferably 500 or less, and particularly preferably 300 or less. The molecular weight of the diamine residue is calculated from the molecular weight of the diamine minus the molecular weight (32) of two amine groups (-NH ₂ ). The diamine residue having a silicon atom in the main chain can be used alone or in combination of two or more.

In addition, in terms of light transmittance and bending resistance and surface hardness, the polyimide having the structure represented by the above general formula (1) is preferably R ² in the above general formula (1) Among them, the diamine residue having a silicon atom in the main chain is a diamine residue having 2 silicon atoms, and from the viewpoint of the ease of acquisition or the balance between light transmittance and surface hardness, it is preferably 1,3 -Bis(3-aminopropyl)tetramethyldisilaxane residue, 1,3-bis(4-aminobutyl)tetramethyldisilaxane, 1,3-bis(5-amine Pentyl) tetramethyl disilaxane and so on.

The diamine residue having no silicon atom and having an aromatic ring in R ² of the above general formula (1) may be a residue obtained by removing two amine groups from a diamine having no silicon atom and having an aromatic ring . As the diamine having no silicon atom and having an aromatic ring, for example, p-phenylenediamine, m-phenylenediamine, o-phenylenediamine, 3,3'-diaminodiphenyl ether, 3,4'- Diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4 '-Diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone Aniline, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2-bis(3-amine Phenyl) propane, 2,2-bis(4-aminophenyl)propane, 2-(3-aminophenyl)-2-(4-aminophenyl)propane, 2,2-bis( 3-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-bis(4-aminophenyl)-1,1,1,3,3,3- Hexafluoropropane, 2-(3-aminophenyl)-2-(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 1,1-bis(3- Aminophenyl)-1-phenylethane, 1,1-bis(4-aminophenyl)-1-phenylethane, 1-(3-aminophenyl)-1-(4- Aminophenyl)-1-phenylethane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis (3-Aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminobenzyl)benzene, 1,3-bis( 4-aminobenzyl)benzene, 1,4-bis(3-aminobenzyl)benzene, 1,4-bis(4-aminobenzyl)benzene, 1,3-bis (3-Amino-α,α-dimethylbenzyl)benzene, 1,3-bis(4-amino-α,α-dimethylbenzyl)benzene, 1,4-bis(3-amine -Α,α-dimethylbenzyl)benzene, 1,4-bis(4-amino-α,α-dimethylbenzyl)benzene, 1,3-bis(3-amino-α, α-Di-trifluoromethylbenzyl)benzene, 1,3-bis(4-amino-α,α-di-trifluoromethylbenzyl)benzene, 1,4-bis(3-amino- α,α-di-trifluoromethylbenzyl)benzene, 1,4-bis(4-amino-α,α-di-trifluoromethylbenzyl)benzene, 2,6-bis(3-amine Phenoxy)benzonitrile, 2,6-bis(3-aminophenoxy)pyridine, N,N'-bis(4-aminophenyl)p-xylylenediamine, 9,9- Bis(4-aminophenyl) stilbene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-di Aminobiphenyl (2,2-bis(trifluoromethyl)benzidine), 3,3'-dichloro-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4 ,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4 ,4'-bis(3-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)biphenyl, bis[4-(3-aminophenoxy)phenyl ] Ketone, bis[4-(4-aminophenoxy)phenyl] ketone, bis[4-(3-aminophenoxy)phenyl] sulfide, bis[4-(4-aminobenzene Oxy)phenyl] sulfide, bis[4-(3-aminophenoxy)phenyl] lanthanum, bis[4-(4-aminophenoxy)phenyl] lanthanum, bis[4-( 3-aminophenoxy)phenyl] ether, bis[4-(4-aminophenoxy)phenyl] ether, 2,2-bis[4-(3-aminophenoxy)phenyl ]Propane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1, 1,3,3,3-hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 1 ,3-bis[4-(3-aminophenoxy)benzyl]benzene, 1,3-bis[4-(4-aminophenoxy)benzyl]benzene, 1,4 -Bis[4-(3-aminophenoxy)benzyl]benzene, 1,4-bis[4-(4-aminophenoxy)benzyl]benzene, 1,3-bis [4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-aminophenoxy)-α,α-dimethyl Benzyl]benzene, 1,4-bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,4-bis[4-(4-aminophenoxy Group)-α,α-dimethylbenzyl]benzene, 4,4'-bis[4-(4-aminophenoxy)benzyl]diphenyl ether, 4,4'-bis[4 -(4-Amino-α,α-dimethylbenzyl)phenoxy]benzophenone, 4,4'-bis[4-(4-amino-α,α-dimethylbenzyl )Phenoxy] diphenyl sulfone, 4,4'-bis[4-(4-aminophenoxy)phenoxy] diphenyl sulfone, 3,3'-diamino-4,4' -Diphenoxybenzophenone, 3,3'-diamino-4,4'-biphenyloxybenzophenone, 3,3'-diamino-4-phenoxybenzophenone Methone, 3,3'-diamino-4-biphenoxybenzophenone, 6,6'-bis(3-aminophenoxy)-3,3,3',3'-tetra Methyl-1,1'-spirobiindene, 6,6'-bis(4-aminophenoxy)-3,3,3',3'-tetramethyl-1,1'-spirobiindene Etc., and the partial substitution of part or all of the hydrogen atom on the aromatic ring of the above diamine with a substituent selected from the group consisting of fluoro, methyl, methoxy, trifluoromethyl, or trifluoromethoxy These amines can be used alone or in combination of two or more.

The diamine residue that does not have a silicon atom and has an aliphatic ring in R ² of the general formula (1) may be a residue obtained by removing two amine groups from the diamine having an aliphatic ring. Examples of the diamine having an aliphatic ring include 1,4-cyclohexanediamine, trans-1,4-bismethylenecyclohexanediamine, and 2,6-bis(aminomethyl)bicyclic [2,2,1]heptane, 2,5-bis(aminomethyl)bicyclo[2,2,1]heptane, etc. These can be used alone or in combination of two or more.

R polyimide film used in the present invention by the above general formula (1) of ^2, 2.5 mole% of the total amount of R ² and 50 mole% or less in the main chain of silicon atoms with a diamine Residues, and 50 mol% or more and 97.5 mol% or less are diamine residues having no silicon atom and having an aromatic ring or an aliphatic ring, so that the static bending resistance and the dynamic bending resistance are good. In terms of bending resistance, R ^{2 in} the general formula (1) is preferably a diamine residue having a silicon atom in the main chain of 3 mole% or more of the total amount of R ² , and more preferably 4 mole Ear% or more, and more preferably 5 mole% or more. In addition, in terms of reducing optical strain, the diamine residue having a silicon atom in the main chain may be 10 mol% or more of the total amount of R ² or 15 mol% or more. On the other hand, in terms of improving surface hardness and light transmittance, R ^{2 in the} above general formula (1) is preferably a diamine residue having a silicon atom in the main chain being 45 mole% of the total amount of R ² Below, it is further preferably 40 mol% or less, and in terms of both excellent surface hardness and dynamic bending resistance, it is also preferably less than 10 mol%. On the other hand, in terms of improving surface hardness and light transmittance, the diamine residue having no silicon atom and having an aromatic ring or an aliphatic ring is preferably 55 mole% or more of the total amount of R ² , and It is preferably 60 mol% or more, and in terms of excellent surface hardness, it can also exceed 90 mol%. Further, in terms of bending resistance, the diamine residue having no silicon atom and having an aromatic ring or an aliphatic ring is preferably 97 mole% or less of the total amount of R ² , and more preferably 96 mole % Or less, and more preferably 95 mole% or less. Furthermore, if satisfying 2.5 mole% or more and 50 mole% or less of the total amount of R ² is a diamine residue having a silicon atom in the main chain and 50 mole% or more and 97.5 mole% or less is not having a silicon atom And having a diamine residue of an aromatic ring or an aliphatic ring, then R ^{2 of} the above general formula (1) may also include a diamine residue having a silicon atom to the main chain and having no aromatic ring or a silicon atom The diamine residue of the aliphatic ring is different from other diamine residues. The other diamine residue is preferably 10 mol% or less of the total amount of R ² , more preferably 5 mol% or less, still more preferably 3 mol% or less, and particularly preferably 1 mol% or less. Examples of the other diamine residues include diamine residues having no silicon atom and having no aromatic ring or aliphatic ring.

Among them, in terms of improving both the bending resistance and the surface hardness, it is preferable that R ² in the general formula (1) represents a diamine residue selected from a group having no silicon atom, and has 1 in the main chain A divalent group of at least one diamine residue of 2 or 2 silicon atoms, 2.5 mole% or more and 50 mole% or less of the total amount of R ² is a diamine having 1 or 2 silicon atoms in the main chain Residues, and 50 mol% or more and 97.5 mol% or less are diamine residues having no silicon atom and having an aromatic ring or an aliphatic ring. In terms of improving bending resistance, R ^{2 of the} above general formula (1) is preferably a diamine residue having 1 or 2 silicon atoms in the main chain of 3 mole% or more of the total amount of R ² , Furthermore, it is preferably 4 mol% or more, and more preferably 5 mol% or more. In addition, in terms of reducing optical strain, the diamine residue having 1 or 2 silicon atoms in the main chain may be 10 mol% or more of the total amount of R ² or 15 mol% or more. On the other hand, in terms of improving surface hardness and light transmittance, R ^{2 in the} above general formula (1) is preferably a total of R ² diamine residues having 1 or 2 silicon atoms in the main chain It is preferably 45 mol% or less, and more preferably 40 mol% or less, and it is also preferably less than 10 mol% in terms of both the excellent surface hardness and the dynamic bending resistance. Wherein, preferably less than 2.5 mole% of the total amount of R ² and 50 mole% or less in the main chain diamines having 1 or 2 atoms of silicon residue, R ² total (100 mole%) of , The remaining amount (100%-x%) of the above mole% (x mole %) of the diamine residues having 1 or 2 silicon atoms in the main chain, ie more than 50 mole% and 97.5 mole% The following are diamine residues having no silicon atom and having an aromatic ring or an aliphatic ring. In addition, in terms of both excellent surface hardness and dynamic bending resistance, it is also preferably 2.5 mole% or more of the total amount of R ² and less than 10 mole% having 1 or 2 in the main chain The remaining diamine residues of 1 silicon atom, the total amount of R ² (100 mol%), the remaining mol% (x mol%) of the above diamine residues having 1 or 2 silicon atoms in the main chain The amount (100%-x%), that is, more than 90 mol% and 97.5 mol% or less is a diamine residue having no silicon atom and having an aromatic ring or an aliphatic ring.

In addition, in terms of bending resistance and surface hardness, the polyimide used in the present invention preferably has a silicon atom content ratio (mass %) of 0.7% by mass or more and 6.5% by mass in the polyimide. Below, it is more preferably 0.7 mass% or more and 5.5 mass% or less, and further preferably 0.7 mass% or more and 4.2 mass% or less. Here, regarding the content ratio (mass %) of silicon atoms in polyimide, when there are two or more types of polyimide, it means the content of silicon atoms in all polyimides of two or more types The ratio (mass %) can be obtained from the molecular weight added during the production of polyimide as follows. In addition, the content ratio (mass %) of silicon atoms in the polyimide can be obtained by using high-performance liquid chromatography, gas chromatography mass spectrometry, NMR on the obtained decomposition product of the polyimide in the same manner as described below , Elemental analysis, XPS/ESCA and TOF-SIMS. (Silicone content ratio of polyimide (mass%)) For example, for 1,4'-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) as 1 mole of acid dianhydride component, use 2,2'-bis(tris) as diamine component In the case of fluoromethyl) benzidine (TFMB) 0.9 moles and 1,3-bis(3-aminopropyl)tetramethyldisilaxane (AprTMOS) 0.1 moles, it can be calculated as follows. The molecular weight of the polyimide repeating unit 1 molar amount is based on From 6FDA: (C) 12.01×19+(F) 19.00×6+(O) 16.00×4+(H) 1.01×6=412.25 From TFMB: {(C) 12.01×14+(F) 19.00×6+(N) 14,01×2+(H) 1.01×6}×0.9=284.60 From AprTMOS: {(C) 12.01×10 + (O) 16.00 × 1 + (N) 14.01 × 2 + (Si) 28.09 × 2 + (H) 1.01 × 24} × 0.1 = 24.45, Calculated as 412.25 + 284.60 + 24.45 = 721.30. The content ratio (mass %) of silicon atoms in 1 mole of polyimide repeat unit was determined as (28.09×2×0.1)/721.30×100=0.8 (mass %).

As the polyimide having the structure represented by the above general formula (1), in terms of improving light transmittance and improving surface hardness, among them, it is preferably a polyimide containing an aromatic ring and containing the following structure , The above structure is selected from the group consisting of (i) a fluorine atom, (ii) an aliphatic ring, and (iii) a structure in which aromatic rings are connected to each other by an alkylene group which may be substituted with sulfonyl or fluorine At least one of them. The polyimide having the structure represented by the above general formula (1) changes the molecular skeleton by including at least one selected from a tetracarboxylic acid residue having an aromatic ring and a diamine residue having an aromatic ring It is rigid, the alignment is improved, and the surface hardness is improved, but the absorption wavelength of the rigid aromatic ring skeleton tends to extend to a long wavelength, and the transmittance of the visible light region tends to decrease. If the polyimide contains (i) a fluorine atom, the electronic state in the polyimide skeleton cannot be easily subjected to charge transfer, and in this respect, the light transmittance is improved. If the polyimide contains (ii) an aliphatic ring, the charge transfer in the skeleton can be hindered by cutting off the conjugation of the π electrons in the polyimide skeleton. In this respect, the light transmittance is improved . If the polyimide contains (iii) a structure in which aromatic rings are connected to each other by an alkylene group which may be substituted by sulfonyl or fluorine, the π electrons in the polyimide skeleton can be conjugated by Cut off and hinder charge transfer in the skeleton, in this respect, the light transmittance is improved.

As the polyimide having the structure represented by the general formula (1), among them, in terms of improving the light transmittance and increasing the surface hardness, a polyimide containing a fluorine atom can be preferably used. The content ratio of fluorine atoms is preferably the ratio (F/C) of the number of fluorine atoms (F) to the number of carbon atoms (F/C) measured on the surface of the polyimide by X-ray photoelectron spectroscopy is more than 0.01, and Preferably it is 0.05 or more. On the other hand, if the content ratio of fluorine atoms is too high, the original heat resistance of polyimide may be reduced. Therefore, the ratio of the number of fluorine atoms (F) to the number of carbon atoms (C) (F/C ) Is preferably 1 or less, and more preferably 0.8 or less. Here, the above ratio obtained by measurement by X-ray photoelectron spectroscopy (XPS) can be obtained from the atomic% value of each atom measured using an X-ray photoelectron spectroscopy device (for example, Thermo Scientific, Theta Probe) .

In addition, regarding the polyimide having the structure represented by the general formula (1), in terms of improving the surface hardness, the total of R ¹ and R ² in the general formula (1) is set to 100 In the case of mol%, the total of the tetracarboxylic acid residue having an aromatic ring and the diamine residue having an aromatic ring is preferably 50 mol% or more, more preferably 60 mol% or more, and even more preferably 75 More than %.

In addition, regarding the polyimide having the structure represented by the general formula (1), it is preferable that the tetracarboxylic acid residues of R ¹ and R ² do not have in terms of improving surface hardness and light transmittance. At least one of the diamine residues having a silicon atom and having an aromatic ring or an aliphatic ring contains an aromatic ring and a fluorine atom, and further preferably the tetracarboxylic acid residue of R ¹ and R ² have no silicon atom and have Both the diamine residue of the aromatic ring or the aliphatic ring contains an aromatic ring and a fluorine atom. Regarding the polyimide having the structure represented by the above general formula (1), in terms of improving the surface hardness and light transmittance, the total of R ¹ and R ² in the above general formula (1) is When it is 100 mol%, the sum of the tetracarboxylic acid residue having an aromatic ring and a fluorine atom and the diamine residue having an aromatic ring and a fluorine atom is preferably 50 mol% or more, more preferably 60 mol % Or more, and more preferably 75 mole% or more.

In addition, regarding the polyimide having the structure represented by the above general formula (1), in terms of improving the light transmittance and improving the surface hardness, the bond contained in the polyimide can be preferably used bonded to carbon More than 50% of the hydrogen atoms of the atom are polyimides bonded directly to the hydrogen atoms of the aromatic ring. The ratio of hydrogen atoms (number) directly bonded to the aromatic ring among all hydrogen atoms (number) bonded to carbon atoms contained in the polyimide is preferably 60% or more, and more Better than 70%. In the case where more than 50% of the hydrogen atoms bound to carbon atoms contained in the polyimide are polyimides directly bonded to the hydrogen atoms of the aromatic ring, even if the heating step in the atmosphere is passed, For example, even if it is extended at a temperature above 200°C, it is preferable that the optical characteristics, especially the total light transmittance or the yellowness YI value change less. It is inferred that in the case where more than 50% of the hydrogen atoms contained in the polyimide bonded to the carbon atom are directly bonded to the hydrogen atom of the aromatic ring, the reactivity with oxygen is low, Therefore, the chemical structure of polyimide is not likely to change. Polyimide films are often used for devices that require a processing step that involves heating due to their high heat resistance, but more than 50% of hydrogen atoms bonded to carbon atoms contained in the polyimide film In the case of a polyimide directly bonded to a hydrogen atom of an aromatic ring, there is no need to perform these subsequent steps in an inactive environment in order to maintain transparency, so it has the ability to suppress equipment costs or environmental control costs The advantages of cost. Here, the ratio of hydrogen atoms (number) directly bonded to the aromatic ring in all hydrogen atoms (number) bonded to carbon atoms contained in the polyimide can decompose the polyimide The substance was determined using high performance liquid chromatography, gas chromatography mass spectrometry and NMR. For example, an alkaline aqueous solution or supercritical methanol can be used to decompose the sample, and the decomposition product of the obtained polyimide can be separated by high-performance liquid chromatography, which can be analyzed using gas chromatography mass spectrometry and NMR. The separated peaks are qualitatively analyzed and quantified using high-performance liquid chromatography to determine the hydrogen atoms directly bonded to the aromatic ring of all the hydrogen atoms (number) contained in the polyimide (Number) ratio.

Regarding the polyimide having the structure represented by the general formula (1) above, among the aspects of light transmittance, bending resistance and surface hardness, the above general formula (1) is preferably R ¹ is selected from the group consisting of cyclohexanetetracarboxylic dianhydride residue, cyclopentanetetracarboxylic dianhydride residue, dicyclohexane-3,4,3',4'-tetracarboxylic dianhydride residue, Residues of cyclobutane tetracarboxylic dianhydride, residues of pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride residues, 2,2',3,3'- Biphenyltetracarboxylic dianhydride residue, 4,4'-(hexafluoroisopropylidene) diphthalic anhydride residue, 3,4'-(hexafluoroisopropylidene) diphthalate Anhydride residue, 3,3'-(hexafluoroisopropylidene) diphthalic anhydride residue, 4,4'-oxydiphthalic anhydride residue, and 3,4'-oxydiphthalic acid residue At least one kind of tetravalent group in the group consisting of phthalic anhydride residues. In the above R ¹ , it is preferable to contain these suitable residues in a total amount of 50 mol% or more, more preferably 70 mol% or more, and still more preferably 90 mol% or more. In particular, in terms of good balance between light transmittance and surface hardness, R ¹ in the above general formula (1) is more preferably selected from 4,4′-(hexafluoroisopropylidene) diphthalate Formic anhydride residues, 3,4'-(hexafluoroisopropylidene) diphthalic anhydride residues, 3,3'-(hexafluoroisopropylidene) diphthalic anhydride residues, 4 , 4'-oxydiphthalic anhydride residues, and 3,4'-oxydiphthalic anhydride residues at least one kind of tetravalent group.

As R ^{1 of the} above general formula (1), it is also preferable to select, for example, a residue selected from pyromellitic dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride residue, and 2 ,2',3,3'-biphenyltetracarboxylic dianhydride residues, at least one of which is a group of tetracarboxylic acid residues (group A) suitable for improving rigidity, and Alkanetetracarboxylic dianhydride residue, cyclopentanetetracarboxylic dianhydride residue, dicyclohexane-3,4,3',4'-tetracarboxylic dianhydride residue, cyclobutanetetracarboxylic dianhydride Anhydride residue, 4,4'-(hexafluoroisopropylidene) diphthalic anhydride residue, 3,4'-(hexafluoroisopropylidene) diphthalic anhydride residue, 3, 3'-(hexafluoroisopropylidene) diphthalic anhydride residue, 4,4'-oxydiphthalic anhydride residue, and 3,4'-oxydiphthalic anhydride residue At least one kind of tetracarboxylic acid residue group (group B) suitable for improving light transmittance in the group to be mixed is used. In this case, the content ratio of the above-mentioned tetracarboxylic acid residue group (group A) suitable for improving the rigidity and the tetracarboxylic acid residue group (group B) suitable for improving the light transmittance is higher than that suitable for improving the permeability The optical tetracarboxylic acid residue group (group B) is 1 mole, and the above-mentioned tetracarboxylic acid residue group (group A) suitable for improving rigidity is preferably 0.05 mole or more and 9 mole or less, more preferably It is 0.1 mol or more and 5 mol or less, and more preferably 0.3 mol or more and 4 mol or less. Among them, it is preferable to use 4,4'-(hexafluoroisopropylidene) diphthalic anhydride residue containing fluorine atoms as for improving the surface hardness and light transmittance of the above group B, And at least one of 3,4'-(hexafluoroisopropylidene) diphthalic anhydride residues.

The polyimide having the structure represented by the general formula (1) is preferably R ² in the general formula (1) in terms of light transmittance, bending resistance and surface hardness. The above-mentioned diamine residue having no silicon atom and having an aromatic ring or an aliphatic ring is selected from the group consisting of trans-cyclohexanediamine residue and trans-1,4-bismethylenecyclohexanediamine residue , 4,4'-diaminodiphenyl sulfide residue, 3,4'-diaminodiphenyl sulfide residue, 2,2-bis(4-aminophenyl)propane residue, 3, 3'-bis(trifluoromethyl)-4,4'-[(1,1,1,3,3,3-hexafluoropropane-2,2-diyl)bis(4,1-phenoxy Radical)] diphenylamine residue, 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane residue, 2,2 -Bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane residue, and a divalent group represented by the following general formula (2) The divalent group of at least one of the formed group is particularly preferably selected from the group consisting of 4,4′-diaminodiphenyl sulfone residue, 3 , 4'-diaminodiphenyl sulfone residue, 2,2-bis(4-aminophenyl) propane residue, and the divalent group represented by the following general formula (2) The at least one divalent group is further preferably a divalent group represented by the following general formula (2). As the divalent group represented by the following general formula (2), it is more preferred that R ³ and R ⁴ are perfluoroalkyl groups, among which, perfluoroalkyl groups having 1 to 3 carbon atoms are preferred, and more preferred is Trifluoromethyl or perfluoroethyl. In addition, as the alkyl group in R ³ and R ⁴ in the following general formula (2), an alkyl group having 1 to 3 carbon atoms is preferred, and a methyl group or an ethyl group is more preferred.

（通式（2）中，R³ 及R⁴ 分別獨立表示氫原子、烷基、或全氟烷基）General formula (2)

(In the general formula (2), R ³ and R ⁴ independently represent a hydrogen atom, an alkyl group, or a perfluoroalkyl group)

The content ratio of each repeating unit in the polyimide, and the content ratio (mol %) of each tetracarboxylic acid residue or each diamine residue can be obtained from the molecular weight added when manufacturing the polyimide. In addition, the content ratio (mol %) of each tetracarboxylic acid residue or each diamine residue in the polyimide can be used in the same manner as above for the decomposition product of the obtained polyimide by high performance liquid chromatography Method, gas chromatography mass spectrometry, NMR, elemental analysis, XPS/ESCA and TOF-SIMS.

In the structure represented by the general formula (1), n represents the number of repeating units and is 1 or more. The number of repeating units n in the polyimide is preferably selected according to the structure in such a manner as to show the following preferred glass transition temperature, but it is not particularly limited. The average number of repeating units is usually preferably 10 to 2000, and more preferably 15 to 1000. Furthermore, R ¹ in each repeating unit may be the same or different, and R ² in each repeating unit may be the same or different.

In addition, in terms of strength and bending resistance at the time of film formation, the polyimide having the structure represented by the general formula (1) preferably has a number average molecular weight of 10,000 or more, more preferably 20,000 or more, Furthermore, it is preferably 30,000 or more, and particularly preferably 50,000 or more. The upper limit is not particularly limited, and in terms of easy synthesis and easy acquisition, it is preferably 10,000,000 or less, and more preferably 500,000 or less. Furthermore, the number average molecular weight of the polyimide can be measured in the same manner as the number average molecular weight of the polyimide precursor described below.

Further, in terms of strength and bending resistance at the time of film formation, the polyimide having the structure represented by the general formula (1) preferably has a weight average molecular weight of 20,000 or more, more preferably 30,000 or more, Furthermore, it is preferably 40,000 or more, and particularly preferably 80,000 or more. The upper limit is not particularly limited, and in terms of easy synthesis and easy acquisition, it is preferably 10,000,000 or less, and more preferably 500,000 or less. The weight average molecular weight of polyimide can be determined by gel permeation chromatography (GPC). Specifically, polyimide is made into a 0.1% by weight N-methylpyrrolidone (NMP) solution, and the developing solvent is a 30 mmol% LiBr-NMP solution with a water content of 500 ppm or less, and GPC manufactured by Tosoh is used. The device (HLC-8120, using a column: GPC LF-804 manufactured by SHODEX) was measured under the conditions of sample injection volume 50 μL, solvent flow rate 0.4 mL/min, and 37°C. The weight average molecular weight is determined based on a polystyrene standard sample having the same concentration as the sample.

In addition, as long as the polyimide used in the present invention does not impair the effect of the present invention, a part of it may have a structure different from the structure represented by the general formula (1). The polyimide used in the present invention is preferably a structure represented by the general formula (1) above 95% of the total number of repeating units of the polyimide, more preferably 98% or more, and still more preferably 100% . Examples of the structure different from the structure represented by the general formula (1) include, for example, a case including a tetracarboxylic acid residue that does not have an aromatic ring or an aliphatic ring, or a polyamide structure. Examples of the polyacrylamide structure that can be included include polyimide and imide structures containing tricarboxylic acid residues such as trimellitic anhydride, and polyacid containing dicarboxylic acid residues such as terephthalic acid. Amine structure.

In terms of improving bending resistance, the polyimide used in the present invention is preferably in the tan δ curve, which is the value obtained by dividing the loss elastic modulus by the storage elastic modulus, and exists only in the temperature region above 150°C The apex of the crest. In terms of improving bending resistance or surface hardness, the polyimide used in the present invention is more preferably in the above tan δ curve, and the peak of the peak exists only in the temperature region above 200°C, and further preferably only The peak of the peak exists in the temperature region above 220°C. On the other hand, in terms of reducing the baking temperature, in the above tan δ curve, the apex of the peak is preferably in a temperature region below 380°C. In addition, the polyimide used in the present invention preferably has a peak of a tan δ curve in a temperature range of 150°C or higher and 400°C or lower. In addition, the polyimide used in the present invention preferably has a temperature range of -150°C or more and less than 150°C, and further has a temperature range of -150°C or more and 0°C or less, without a peak of the tan δ curve, thereby , Can increase the surface hardness of polyimide film at room temperature. The tan δ curve of the polyimide used in the present invention can be measured in the same manner as the tan δ curve of the polyimide film described below.

2. Additives The polyimide film of the present invention may contain additives in addition to the above-mentioned polyimide, if necessary. Examples of the above-mentioned additives include inorganic particles, silica fillers for smooth winding, and surfactants for improving film-forming properties or defoaming properties.

3. The characteristics of polyimide membrane The polyimide film of the present invention has the above-mentioned specific residual solvent amount and the above-mentioned specific total light transmittance. The polyimide film of the present invention preferably further has the following characteristics.

(1) The amount of residual solvent Regarding the polyimide film of the present invention, as the residual solvent in the film, the content of the organic solvent with a boiling point of 1 atm not exceeding 100°C is 2000 ppm or less, and the content of the organic solvent with a boiling point of 1 atm being 100°C or more is Below 100 ppm. In terms of improving static bending resistance and dynamic bending resistance, the content of the organic solvent having a boiling point of less than 100°C is preferably 1000 ppm or less, more preferably 400 ppm or less, and further preferably 100 ppm or less. Among them, the content of the organic solvent having a boiling point of 60°C or less may be 2000 ppm or less, preferably 1000 ppm or less, more preferably 400 ppm or less, and further preferably 100 ppm or less. In terms of improving static bending resistance and dynamic bending resistance, the lower the content of the organic solvent having a boiling point of less than 100°C, the better, and it may be 0 ppm. On the other hand, in terms of improving the dynamic bending resistance, the content of the organic solvent having a boiling point of 100° C. or higher is preferably 80 ppm or lower, more preferably 50 ppm or lower, further preferably 30 ppm or lower, and still more preferably Below 20 ppm. In terms of improving the resistance to dynamic bending, the content of the organic solvent having a boiling point of 100°C or higher is also as small as possible, and may be 0 ppm. The content of the organic solvent with a boiling point of 1 atm or below 70°C is 2000 ppm or less, and the content of the organic solvent with a boiling point of 1 atm and above 70°C is 100 ppm or less, and furthermore, the boiling point of 1 atm is below 60°C The content of the organic solvent is 2000 ppm or less and the content of the organic solvent with a boiling point of more than 60°C at 1 atmosphere pressure is 100 ppm or less. Furthermore, the content of the organic solvent with a boiling point of 1 atmosphere at 50°C or less may be 2000 ppm or less And the content of the organic solvent with a boiling point of more than 50°C at 1 atmosphere is 100 ppm or less.

The organic solvent used in the production step of the polyimide film can be exemplified as the organic solvent with a boiling point of not more than 100°C at 1 atmosphere included in the form of a residual solvent, for example, chloroform, carbon tetrachloride, 1,2 -Dichloroethane, 1,2-dichloroethylene, trichloroethylene, acetone, isopropanol, diethyl ether, isopropyl acetate, ethyl acetate, methyl acetate, dichloromethane, tetrahydrofuran, 1,1, 1-Trichloroethane, n-hexane, 2-butanol, methanol, methyl ethyl ketone, etc. Among them, examples of organic solvents having a boiling point of 1 atm and a temperature of 70°C or lower include chloroform and 1,2-dichloro Ethylene, acetone, diethyl ether, methyl acetate, dichloromethane, tetrahydrofuran, n-hexane, methanol, etc. The organic solvent used in the manufacturing step of the polyimide film may be exemplified as the organic solvent with a boiling point of 100°C or higher at 1 atmosphere included in the form of a residual solvent, for example, N-methyl-2-pyrrolidine Ketone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphoramide, 1,3-dimethyl-2-imidazolidinone , Γ-butyrolactone, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-butyl ether, ethylene glycol monomethyl ether, o-dichlorobenzene, Xylene, o-cresol, chlorobenzene, isobutyl acetate, isoamyl acetate, n-butyl acetate, n-propyl acetate, n-pentyl acetate, n-butyl acetate, cyclohexanol, cyclohexanone, 1, 4-Dioxane, tetrachloroethylene, toluene, methyl isobutyl ketone, methyl cyclohexanol, methyl cyclohexanone, methyl n-butyl ketone, etc.

The amount of residual solvent in the polyimide film can be measured as follows. [Specification of residual solvent type] First, the type of residual solvent is specified using GC-MS connected with a purge & trap device (heat desorption device). A sample tube with a 10 mg polyimide film is installed in a purge & trap device (product name JTD505-III, Japan Analytical Industries Co., Ltd.), and it is heated at 200°C for 30 minutes and heated at -60°C. The trapped tube collects the generated gas, heats the trapped person at 315°C and scatters it, and sends it to GC-MS to perform qualitative analysis on the composition of the generated organic gas. (Conditions of Purge & Capture Device) Total split ratio (introduction/exhaust) 1:10, Carrier gas helium 1.0 ml/min (GC-MS conditions) Device name: GC-MS device (Agilent, 6890/5973 GC/MS) Column: UA-5 inner diameter 250 μm × length 30 m × film thickness 0.25 μm (manufactured by Frontier Laboratories), heating conditions 50°C (hold 5 minutes) → 10°C/min (heating) → 320°C (hold 3 minutes)

[Quantification of residual solvent] Polyimide film was added to N,N-dimethylformamide (DMF) in such a way that the concentration of the polyimide film became 5 mass% to prepare a polyimide film /N,N-dimethyl A methylformamide (DMF) solution, to which was added an internal standard solution (0.2% by mass concentration anisole/DMF solution) to prepare a sample solution. For this sample solution, a GC-MS device (for example, Agilent Corporation, 6890/5973 GC/MS) was used to perform GC-MS measurement under the following conditions. This GC-MS measurement was performed three times, and the measurement result was set as the average of three times. (GC conditions) Column: InertCapWax inner diameter 250 μm×length 30 m×film thickness 0.25 μm (manufactured by GL Science), Sample injection volume 0.2 μL, split ratio (introduction/exhaust volume) 1:50, carrier gas is helium 94.3 kPa constant pressure, injection port temperature 250℃, heating condition 40℃ (hold 5 minutes) → 5℃/min →120℃→20℃/min→240℃ (hold for 6 minutes), conveyor line temperature 250℃ (MS conditions) Ionization method EI, measurement mode SIM, ion source temperature 250℃, quadrupole temperature 150℃, ionization voltage 70 eV

A calibration curve is prepared for each residual solvent specified in the above manner, and the amount of each residual solvent is quantified based on the calibration curve. For example, when the residual solvent included is N,N-dimethylacetamide (DMAc), each prepared in such a way that the DMAc content becomes 0.01% by mass, 0.05% by mass, and 0.1% by mass, for example In the DMAc (compound to be measured)/DMF solution, an internal standard solution was added in the same manner as the above sample solution to prepare each calibration curve liquid, and each calibration curve liquid was subjected to GC-MS measurement to prepare a calibration curve. In addition, GC-MS measurement was performed 3 times, and the measurement result was set as the average value of 3 times. Then, based on the calibration curve, the content of DMAc is calculated as the mass ratio to the polyimide film. Furthermore, the calibration curve is appropriately recreated according to the detection amount. When there are more than two kinds of residual solvents, a calibration curve liquid is prepared for each residual solvent in the same manner as the above DMAc, GC-MS measurement is performed on each calibration curve liquid, and a calibration curve is prepared based on the measurement results, and This calibration curve is used as a reference. Furthermore, in the case where N,N-dimethylformamide (DMF) is included as a residual solvent, for example, it is preferable to use polyimide such as N-methyl-2-pyrrolidone that is not included as a residual solvent. Solvent, prepare sample solution.

(2) Full light transmittance In addition, the polyimide film of the present invention has a total light transmittance of 85% or more as measured according to JIS K7361-1. Such a high penetration rate, therefore, the transparency becomes good and can be used as a substitute for glass. The above-mentioned total light transmittance measured according to JIS K7361-1 of the polyimide film of the present invention is more preferably 88% or more, still more preferably 89% or more, and particularly preferably 90% or more.

The total light transmittance measured according to JIS K7361-1 can be measured by a haze meter (for example, HM150 manufactured by Murakami Color Technology Research Institute). Furthermore, according to the measured value of the total light transmittance of a certain thickness, the converted value of the total light transmittance of different thicknesses can be obtained by Lambert-Beer law, and this value can be used. Specifically, according to the Lambert-Beer law, the transmittance T is represented by Log ₁₀ (1/T)=kcb (k=intrinsic constant of the substance, c=concentration, b=optical path length). In the case of film penetration, it is assumed that even if the film thickness changes, the density is also constant, so c also becomes a constant, so the above formula can use the constant f, expressed as Log ₁₀ (1/T) = fb (f = kc). Here, as long as the penetration rate at a certain film thickness is known, the inherent constant f of each substance can be obtained. Therefore, using the formula of T = 1/10 ^{f · b} , f is substituted into the intrinsic constant, and b is substituted into the target film thickness, the penetration rate at the required film thickness can be obtained.

(3) Yellowness In addition, the polyimide film of the present invention preferably has a yellowness (YI value) calculated according to JIS K7373-2006 of 12 or less. If the yellowness is so low, the coloration of the yellow tone is suppressed, the light transmittance is improved, and it can be used as a substitute for glass. The yellowness (YI value) calculated according to JIS K7373-2006 is preferably 10 or less, more preferably 7 or less, and still more preferably 5 or less. In addition, the yellowness (YI value) can be used in accordance with the above-mentioned JIS K7373-2006 using an ultraviolet-visible near-infrared spectrophotometer (for example, Japan Spectroscopy Co., Ltd. V-7100), using a spectrophotometric color measurement method, using auxiliary illuminators C, 2 The field of view is measured at 1 nm intervals in the range above 250 nm and below 800 nm. Based on the measured penetration, the three stimulus values X, Y, Z in the XYZ color system are obtained. According to the X, The values of Y and Z are calculated by the following formula. YI＝100（1.2769X－1.0592Z）/Y In addition, according to the measured value of the yellowness of a certain thickness, the yellowness of different thicknesses can be measured at a wavelength of 1 nm between 250 nm and 800 nm of a sample of a specific film thickness at each wavelength. The transmittance is the same as the above-mentioned total light transmittance, and the converted value of each transmittance at each wavelength with different thickness is obtained by the Lambert-Beer law, and is calculated based on the converted value and used.

In addition, regarding the polyimide film of the present invention, the yellowness calculated according to JIS K7373-2006 described above is used in terms of suppressing the coloration of the yellow tone, improving light transmittance, and being suitable for use as a glass substitute material ( The value (YI value) divided by the film thickness (μm) (YI value/film thickness (μm)) is preferably 0.10 or less, more preferably 0.04 or less, and even more preferably 0.03 or less. Furthermore, in the present invention, the value obtained by dividing the above-mentioned yellowness (YI value) by the film thickness (μm) (YI value/film thickness (μm)) is in accordance with Rule B of JIS Z8401: 1999, and is rounded to The value of the second digit after the decimal point.

(4) Tensile elastic modulus The polyimide film of the present invention is preferably measured at a temperature of 25°C measured on a 15 mm×40 mm test piece in accordance with JIS K7127 with a stretching speed of 10 mm/min and a distance between chucks of 20 mm. The tensile modulus of elasticity is 1.8 GPa or more. In this way, the tensile modulus of elasticity at 25°C (room temperature) is high, and even at room temperature, it can maintain sufficient surface hardness as a protective film, and can be used as a surface material or substrate. The tensile elastic modulus is preferably 2.0 GPa or more, more preferably 2.1 GPa or more, and further preferably 2.3 GPa or more. On the other hand, in terms of improving bending resistance, the tensile elastic modulus is preferably 5.2 GPa or less. In terms of improving bending resistance, the above tensile elastic modulus may be 4.0 GPa or less, 3.5 GPa or less, or 2.9 GPa or less. The above tensile elastic modulus can use a tensile testing machine (for example, manufactured by Shimadzu Corporation: Autograph AG-X 1N, load cell: SBL-1KN), and a test piece with a width of 15 mm and a length of 40 mm is cut from the polyimide film. The test piece was measured at 25° C., with a stretching speed of 8 mm/min and a distance between chucks of 20 mm. The polyimide film when the tensile elastic modulus is obtained is preferably 55 μm±5 μm in thickness.

(5) tanδ curve The polyimide film of the present invention is preferably a tan δ curve obtained by dividing the loss elastic modulus by the storage elastic modulus, and the peak of the peak exists only in the temperature region above 150°C. The reason is that if the apex of the peak in the above tan δ curve is less than 150°C, the molecular chain of the polyimide is likely to move, and plastic deformation is likely to occur, and the bending resistance may be deteriorated. If the peak of the peak does not exist below 150°C, the mobility of the molecular chain can be suppressed, plastic deformation is not likely to occur, and the bending resistance is improved. In addition, if the peak of the peak exists only in the temperature range above 150°C in the above tan δ curve, under high temperature environment, such as in a car in summer, etc., the damage to bending resistance due to thermal deformation is also suppressed. Bending resistance has also been improved in high temperature environments. In addition, if the peak of the peak exists only in the temperature range of 150° C. or higher in the above tan δ curve, the tensile elastic modulus tends to increase, and the surface hardness tends to increase. In terms of improving bending resistance or surface hardness, the polyimide film of the present invention is more preferably in the above tan δ curve, the peak of the peak exists only in the temperature region above 200°C, and is more preferably only 220 The peak of the peak exists in the temperature region above ℃. On the other hand, in terms of reducing the baking temperature, it is preferable that in the above tan δ curve, the peak of the peak is located in a temperature region below 380°C. Moreover, regarding the polyimide film of the present invention, it is preferable that the temperature region above -150°C and below 150°C does not have the peak apex in the tan δ curve described above, and further preferably above -70°C and above The temperature region up to 150°C does not have the peak apex in the above tanδ curve, further preferably the temperature region below 100°C does not have the peak apex in the above tanδ curve, and more preferably the temperature region below 0°C does not have The apex of the peak in the above tan δ curve. In the case of containing a diamine residue with a long siloxane bond in the main chain or a large amount of diamine residues with a silicon atom in the main chain, there is such a tanδ curve in the lower temperature region The peak of the peak. The above tanδ curve is determined by dynamic viscoelasticity, according to the relationship between temperature and tanδ (tanδ = loss elastic modulus (E'')/storage elastic modulus (E')), the maximum value of the peak can be The temperature at the peak of the largest peak is set as an index of the glass transition temperature. For dynamic viscoelasticity measurement, for example, the dynamic viscoelasticity measurement device RSA-G2 (TA Instruments Japan Co., Ltd.) can be used to set the measurement range to -150°C or more and 490°C or less, at a frequency of 1 Hz and a heating rate of 5°C/min get on. In addition, it is possible to measure by setting the sample width to 5 mm and the distance between the chucks to 20 mm. When analyzing peaks and inflection points, the data is digitized without visual evaluation, and the analysis is performed based on the numerical values. Furthermore, in the curve of temperature (horizontal axis) and tanδ (tanδ=loss elastic modulus (E'')/storage elastic modulus (E′)) (vertical axis), the peak means that the tanδ value is 0.2 or more, Preferably it is 0.3 or more and has a maximum value, and the peak width between the peaks and valleys, that is, the peak width is 3°C or more, and the slight fluctuations in the curve from the measurement of noise etc. are not observed as the peak of the peak crest. As a sample for measuring the tan δ curve, the following is used: a polyimide film that is allowed to stand for 24 hours in an environment of 23°C ± 2°C and RH 30 to 50% to make a sample film of 10 cm square or more, using a razor or surgery Use a knife to cut a jig with a slit of 5 mm width, and then cut the center of the resulting sample film to a width of 5 mm × length 50 mm (in a way that the sample length becomes 20 mm when clamped) By. The width is measured by using a vernier caliper, and the average value of three measurements is changed and recorded. At this time, when there is a variation range of more than 3% of the average value in a part of the width measurement, the sample is not used.

(6) Pencil hardness In the polyimide film of the present invention, the pencil hardness is preferably 2B or more, more preferably B or more, and still more preferably HB or more. The pencil hardness of the polyimide film can be measured by adjusting the measured sample at a temperature of 25°C and a relative humidity of 60% for 2 hours and then using the test specified in JIS-S-6006 For pencils, the pencil hardness test (0.98 N load) specified in JIS K5600-5-4 (1999) was performed on the film surface, and the highest pencil hardness without damage was evaluated. For example, a pencil scratch coating film hardness tester manufactured by Toyo Seiki Co., Ltd. can be used.

(7) In addition, the adhesion of the film, in the polyimide film of the present invention, when the adhesion test is performed according to the following adhesion test method, the peeling of the coating film does not occur, so the polyimide film It is preferable in terms of the adhesion to the hard coat layer and the surface hardness of the laminate obtained by laminating the hard coat layer adjacent to the polyimide film. [Adhesion Test Method] In a 40% by mass methyl isobutyl ketone solution of neopentaerythritol triacrylate, 10 parts by mass of 1-hydroxycyclohexylbenzene is added to 100 parts by mass of neopentaerythritol triacrylate. Base resin to prepare a resin composition for evaluation of adhesion, and apply the prepared resin composition for evaluation of adhesion to a test piece cut into a polyimide film of 10 cm×10 cm, under a nitrogen gas flow at 200 mJ The exposure amount of /cm ² is irradiated with ultraviolet rays to harden it, thereby forming a cured film with a thickness of 10 μm. For this cured film, a cross-cut test in accordance with JIS K5600-5-6 was performed, and the peeling operation with tape was repeated five times, and the presence or absence of peeling of the coating film was observed.

4. Composition of polyimide film The thickness of the polyimide film of the present invention may be appropriately selected according to the application, and is preferably 1 mm or more, more preferably 5 μm or more, and still more preferably 10 μm or more. On the other hand, it is preferably 200 μm or less, further preferably 150 μm or less, still more preferably 100 μm or less, and still more preferably 90 μm or less. If the thickness is thin, the strength may be reduced. If the thickness is thick, the difference between the inner diameter and the outer diameter during bending may increase, and the load on the film may increase, so the bending resistance may decrease.

In addition, the polyimide film of the present invention may be subjected to surface treatments such as saponification treatment, glow discharge treatment, corona discharge treatment, ultraviolet treatment, and flame treatment.

5. Manufacturing method of polyimide film The method for producing the polyimide film of the present invention is not particularly limited as long as it can produce the polyimide film of the present invention described above. <First Manufacturing Method> Regarding the method for manufacturing the polyimide film of the present invention, for example, as the first manufacturing method, a method for manufacturing the polyimide film including the following steps may be mentioned: Preparing a polyimide precursor resin composition containing polyimide as a polyimide precursor and an organic solvent (hereinafter referred to as a preparation step of a polyimide precursor resin composition); Applying the above polyimide precursor resin composition to a support to form a polyimide precursor resin coating film (hereinafter referred to as a polyimide precursor resin coating film forming step); and By heating, the aforementioned polyimide precursor is imidized (hereinafter referred to as an imidization step). The method for manufacturing the polyimide film of the present invention preferably further includes the following steps: measuring the residual solvent amount of the obtained polyimide film, as the residual solvent in the film, and judging that the boiling point of 1 atmospheric pressure has not reached 100°C Whether the content of the organic solvent is 2000 ppm or less, and whether the content of the organic solvent with a boiling point of 1 atmosphere at 100°C or higher is 100 ppm or less. In the case where the residual solvent amount of the obtained polyimide film exceeds the value specified in the present invention, it is preferable to make the polyimide film by further performing the step of heating the polyimide film The amount of residual solvent is below the value specified in the present invention.

In the first manufacturing method, the polyimide precursor resin coating film may be further included, and the polyimide precursor resin coating film may be imidized after the imidization. At least one of them performs an extension step (hereinafter referred to as an extension step). Hereinafter, each step will be described in detail.

(1) Preparation step of polyimide precursor resin composition The polyimide precursor resin composition to be prepared in the first manufacturing method described above contains the polyimide precursor and the organic solvent, and may also contain additives if necessary. Examples of the polyimide precursors include polyimide precursors represented by the following general formula (1′). The polyimide precursor represented by the above general formula (1') is formed by the tetracarboxylic acid component which becomes the tetracarboxylic acid residue in R ¹ of the above general formula (1') and becomes the above general formula (1' ) Polyamide obtained by polymerization of the diamine component of the diamine residue in R ² .

（通式（1'）中，R¹ 、R² 及n與上述通式（1）相同）General formula (1')

(In the general formula (1'), R ¹ , R ² and n are the same as the general formula (1) above)

Here, R ¹ , R ² and n of the above general formula (1′) may be the same as R ¹ , R ² and n of the above general formula (1) described in the above polyimide.

Regarding the polyimide precursor represented by the above general formula (1'), it is preferable that at least any one of the number average molecular weight or the weight average molecular weight is 10,000 or more in terms of strength at the time of forming the film, Furthermore, it is preferably 20,000 or more. Further, in terms of improving bending resistance, the polyimide precursor represented by the general formula (1′) preferably has a weight average molecular weight of 70,000 or more, more preferably 80,000 or more, and even more preferably 85,000 the above. On the other hand, if the average molecular weight is too large, there is a possibility that the viscosity will be high and the workability such as filtration may decrease. In this respect, it is preferably 10,000,000 or less, and more preferably 500,000 or less. The number average molecular weight of the polyimide precursor can be determined by NMR (for example, AVANCE III manufactured by BRUKER). For example, a polyimide precursor solution can be coated on a glass plate, dried at 100°C for 5 minutes, and 10 mg of the solid content is dissolved in dimethyl sulfoxide-d6 solvent 7.5 ml to perform NMR measurement. The number-average molecular weight is calculated from the peak intensity ratio of the hydrogen atoms bound to the aromatic ring. The weight average molecular weight of the polyimide precursor can be measured by gel permeation chromatography (GPC). The polyimide precursor was made into a 0.5% by weight N-methylpyrrolidone (NMP) solution, and the developing solvent used a 10 mmol% LiBr-NMP solution with a water content of 500 ppm or less, using a GPC device manufactured by Tosoh ( HLC-8120, using a column: GPC LF-804 manufactured by SHODEX), was measured under the conditions of sample injection volume of 50 μL, solvent flow rate of 0.5 mL/min, and 40°C. The weight average molecular weight is calculated based on a polystyrene standard sample at the same concentration as the sample.

The polyimide precursor solution is obtained by reacting the tetracarboxylic dianhydride and the diamine in a solvent. The solvent used for synthesizing the polyimide precursor (polyamide) is not particularly limited as long as it can dissolve the above-mentioned tetracarboxylic dianhydride and diamine. For example, an aprotic polar solvent or a water-soluble alcohol can be used Department of solvents. In the present invention, it is preferable to use N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, hexamethylene Organic solvents containing nitrogen atoms such as methylphosphoramide, 1,3-dimethyl-2-imidazolidinone; γ-butyrolactone, etc. Among them, when the above-mentioned polyimide precursor solution (polyamide acid solution) is directly used to prepare the polyimide precursor resin composition, it is preferable to use an organic solvent containing a nitrogen atom, particularly preferably Use N,N-dimethylacetamide, N-methyl-2-pyrrolidone, or a combination of these. Furthermore, the organic solvent is a solvent containing carbon atoms.

In addition, when at least two kinds of diamines are combined to prepare the above polyimide precursor solution, an acid dianhydride can be added to a mixed solution of at least two kinds of diamines to synthesize the polyamic acid. At least two diamine components are added to the reaction solution in stages at appropriate molar ratios, and the sequence in which each raw material is incorporated into the polymer chain is controlled to some extent. For example, it is also possible to synthesize the main solution by adding 0.5 equivalents of molar molar acid dianhydride of the main chain diamine having silicon atom to the reaction solution in which the main chain diamine having silicon atom is dissolved and reacting it. The amide acid obtained by the reaction of the diamine with a silicon atom in the chain and the two ends of the acid dianhydride is added to the remaining diamine or a part of the diamine, and the acid dianhydride is added to polymerize the polyamic acid. When polymerization is carried out by this method, the diamine having a silicon atom in the main chain is introduced into the polyamic acid in the form of being connected via one acid dianhydride. In terms of easily obtaining a film that maintains surface hardness and is excellent in bending resistance, the polymerization of polyamic acid by this method specifies the positional relationship of the polyamic acid with a silicon atom in the main chain to some extent, so It is preferable that a film that maintains surface hardness and has excellent bending resistance is easily obtained.

When the number of moles of the diamine in the above polyimide precursor solution (polyamide acid solution) is set to a, and the number of moles of tetracarboxylic dianhydride is set to b, it is preferable to set b/ a is 0.9 or more and 1.1 or less, more preferably 0.95 or more and 1.05 or less, further preferably 0.97 or more and 1.03 or less, and particularly preferably 0.99 or more and 1.01 or less. By setting to such a range, the molecular weight (degree of polymerization) of the obtained polyamide can be adjusted appropriately. The order of the polymerization reaction can be appropriately selected and used by a known method, and is not particularly limited. In addition, the polyimide precursor solution obtained by the synthesis reaction can be directly used, and other components can be mixed therein as needed, or the solvent of the polyimide precursor solution can be dried and removed and dissolved in other solvents. use.

In terms of forming a uniform coating film and a polyimide film, the viscosity of the polyimide precursor solution at 25° C. is preferably 500 cps or more and 200,000 cps or less. The viscosity of the polyimide precursor solution can be measured using a viscometer (eg TVE-22HT, Toki Industry Co., Ltd.) at 25°C.

The above-mentioned polyimide precursor resin composition may contain additives as needed. Examples of the above-mentioned additives include inorganic particles for reducing the optical strain of the polyimide film, silica fillers for smooth winding, and surfactants for improving film forming or defoaming properties. , The same components as those described in the above polyimide film can be used.

The organic solvent used for the polyimide precursor resin composition is not particularly limited as long as it can dissolve the polyimide precursor. For example, N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphoramide, 1 , 3-dimethyl-2-imidazolidinone and other organic solvents containing nitrogen atoms; γ-butyrolactone, etc. Among them, it is preferable to use organic solvents containing nitrogen atoms for the reasons mentioned above.

In terms of forming a uniform coating film and a polyimide film having operable strength, the content of the polyimide precursor in the polyimide precursor resin composition is in the solid form of the resin composition Among the material components, it is preferably 50% by mass or more, and more preferably 60% by mass or more, and the upper limit may be appropriately adjusted according to the contained component. In terms of forming a uniform coating film and a polyimide film, the organic solvent in the resin composition of the polyimide precursor is preferably 40% by mass or more in the resin composition, and more preferably 50% by mass % Or more, and preferably 99% by mass or less.

In addition, from the viewpoint that the storage stability of the polyimide precursor resin composition becomes good and the productivity can be improved, the polyimide precursor resin composition preferably contains a water content of 1,000 ppm or less. If the polyimide precursor resin composition contains a large amount of water, the polyimide precursor may be easily decomposed. In addition, the water content of the polyimide precursor resin composition can be determined using a Karl Fischer moisture meter (for example, a trace moisture measuring device model CA-200 manufactured by Mitsubishi Chemical Corporation).

In terms of forming a uniform coating film and a polyimide film, the viscosity of the solid content of the polyimide precursor resin composition at 15% by weight at 25°C is preferably 500 cps or more and 100000 cps or less. . The viscosity of the polyimide precursor resin composition can be measured using a viscometer (eg TVE-22HT, Toki Industry Co., Ltd.) at 25°C with a sample volume of 0.8 ml.

(2) Step of forming resin coating film of polyimide precursor In the step of applying the above polyimide precursor resin composition to a support to form a polyimide precursor resin coating film, as the support used, as long as the surface is smooth and has heat resistance and solvent resistance There are no special restrictions on sexual materials. For example, an inorganic material such as a glass plate, a metal plate with a mirror-finished surface, etc. can be mentioned. In addition, the shape of the support is selected according to the coating method, and may be, for example, a plate shape, a roll shape or a belt shape, or a sheet shape that can be wound into a roll.

The coating means is not particularly limited as long as it can be coated with a target film thickness. For example, a die coater, a corner coater, a roll coater, a gravure coater, and a curtain can be used. A well-known person, such as a curtain coater, a spray coater, and a die lip coater. The coating can be performed by a single-piece coating device or a roll-to-roll coating device.

After the polyimide precursor resin composition is applied to the support, it is dried at a temperature of 150° C. or lower, preferably 30° C. or higher and 120° C. or lower, to remove the solvent in the coating film until the coating film becomes non-sticky. By setting the drying temperature of the solvent to 150° C. or lower, the imidization of the polyamic acid can be suppressed.

The drying time may be appropriately adjusted according to the film thickness of the polyimide precursor resin coating film, the type of solvent, the drying temperature, etc., and is usually 1 minute to 60 minutes, preferably 2 minutes to 30 minutes. When the upper limit value is exceeded, the production efficiency of the polyimide film is poor. On the other hand, when the value is lower than the lower limit, the appearance of the obtained polyimide film may be affected by rapid solvent drying.

The drying method of the solvent is not particularly limited as long as the solvent can be dried at the above-mentioned temperature. For example, an oven, a drying furnace, a hot plate, infrared heating, or the like can be used. When high management of optical characteristics is necessary, the environment when the solvent is dried is preferably an inert gas environment. The inert gas environment is preferably a nitrogen environment, and the oxygen concentration is preferably 100 ppm or less, and more preferably 50 ppm or less. If the heat treatment is performed in an atmospheric environment, there is a possibility that the film will be oxidized and coloring or performance will be reduced.

(3) Amidation step In the above-mentioned first production method, the polyimide precursor is imidized by heating. In the present invention, in order to set the residual solvent amount of the polyimide film to the value specified in the present invention or less, it is preferable to perform the following step, that is, by self-coating the polyimide precursor resin coating film The support used in the cloth is peeled and heated, and the polyimide precursor is imidized. By peeling off the support used during coating, and heating in a state where both surfaces of the film are not in contact with the support, etc., the solvent can be volatilized from both surfaces of the film, and the residual solvent can be sufficiently reduced to the present invention Below the value specified in. In addition, in terms of preventing shrinkage during heating, the polyimide precursor resin coating film after peeling from the support is preferably heated after fixing the ends. As a method of fixing the ends of the resin coating film of the polyimide precursor, for example, when the resin coating film of the polyimide precursor is in the form of a sheet, the following method may be mentioned: using two blocks with a polyimide The metal frame of the precursor resin coating film is approximately the same as the outer size and the appropriate inner size. The polyimide precursor resin coating film is sandwiched between the two metal frames and the polyimide precursor resin coating film using a fixture fixed. In addition, for example, in the case where the resin coating film of the polyimide precursor is in a roll shape, for example, the following method may be used: a device capable of conveying the resin film by holding the left and right ends of the continuous resin film with a jig or the like, Fix the end of the resin coating film of the polyimide precursor.

In this manufacturing method, in the case where there is an extension step, the amide imidization step can be performed on the polyimide precursor in the above-mentioned polyimide precursor resin coating film before the extension step, and can be performed on the The polyimide precursor in the above-mentioned polyimide precursor resin coating film is carried out, and the polyimide precursor in the above-mentioned polyimide precursor resin coating film before the extension step and after the extension step can also be performed Both of the polyimide precursors present in the film proceed.

The temperature of the imidate can be appropriately selected according to the structure of the polyimide precursor. Generally, it is preferable to set the temperature increase starting temperature to 30°C or higher, and more preferably to 100°C or higher. On the other hand, the temperature increase end temperature is preferably 250° C. or higher, and more preferably 270° C. or higher. On the other hand, in terms of suppressing poor appearance of the film or a decrease in strength and improving light transmittance, the temperature increase end temperature is preferably 400° C. or lower, and more preferably 350° C. or lower.

The temperature increase rate is preferably appropriately selected according to the film thickness of the obtained polyimide film, and in the case where the film thickness of the polyimide film is thick, it is preferable to reduce the temperature increase rate. In terms of the production efficiency of the polyimide film, it is preferably 5° C./min or more, and more preferably 10° C./min or more. On the other hand, the upper limit of the temperature increase rate is usually 50°C/min, preferably 40°C/min or less, and more preferably 30°C/min or less. In terms of suppressing poor appearance of the film or reduction in strength, and controlling the whitening accompanying the amide imidization reaction to improve the light transmittance, it is preferable to set the above temperature increase rate.

The temperature increase may be carried out continuously or in stages. In order to suppress poor appearance of the film or decrease in strength, and to control the whitening accompanying the amide imidization reaction, it is preferably carried out continuously. In addition, the temperature increase rate can be fixed within the entire temperature range described above, or it can be changed in the middle.

The environment when the temperature of the imidate is heated is preferably an inert gas environment. The inert gas environment is preferably a nitrogen environment, and the oxygen concentration is preferably 500 ppm or less, more preferably 200 ppm or less, and further preferably 100 ppm or less. If the heat treatment is performed in an atmospheric environment, there is a possibility that the film will be oxidized and coloring or performance will be reduced. Among them, when more than 50% of hydrogen atoms bound to carbon atoms contained in the polyimide are hydrogen atoms directly bonded to the aromatic ring, oxygen has less effect on optical properties, even if it is not used In an inert gas environment, polyimide with high light transmittance can also be obtained.

The heating method for imidate is not particularly limited as long as it can raise the temperature at the above temperature, and for example, an oven, a heating furnace, infrared heating, electromagnetic induction heating, or the like can be used.

Among them, it is more preferable to set the imidization ratio of the polyimide precursor to 50% or more before the extending step. By setting the imidization ratio of the amide imide to 50% or more before the stretching step, even if the stretching is performed after this step, and then the imidate is heated at a high temperature for a certain period of time, the film is also suppressed The appearance is bad or white. Among them, in terms of improving the surface hardness of the polyimide film, it is preferable to set the rate of the imidate in the imidate step to 80% or more in the imidate step, preferably to perform the reaction The rate of imidization to 90% or more, and further to 100%. It is presumed that by stretching after the amide imidization, the rigid polymer chain is easily aligned, and thus the surface hardness is improved. Furthermore, the measurement of the amidation rate can be performed by analysis of the spectrum obtained by infrared measurement (IR).

In order to obtain the final polyimide film, it is preferable to proceed the reaction until the imidate is 90% or more, further 95% or more, and further 100%. In order to carry out the reaction until the imidate is 90% or more and further 100%, it is preferable to maintain the temperature at the end of the temperature increase for a certain period of time. The retention time is preferably usually set to 1 minute to 180 minutes, further preferably set From 5 minutes to 150 minutes.

(4) Extension steps The above-mentioned first manufacturing method may further have an extension step of coating the polyimide precursor resin coating film and the polyimide precursor resin coating film after imidization of the polyimide precursor coating film At least one of the films is extended. In the case of having such an extension step, it is preferable to include a step of extending the coating film after the imidization of the polyimide film in terms of improving the surface hardness of the polyimide film.

In the above-mentioned first manufacturing method, it is preferable to perform the step of stretching 101% to 10000% or less when the initial size before stretching is set to 100% while heating at 80° C. or higher. The heating temperature during extension is preferably within the range of glass transition temperature of polyimide or polyimide precursor within ±50°C, preferably within the range of glass transition temperature within ±40°C. If the elongation temperature is too low, the film may not be deformed and alignment may not be sufficiently induced. On the other hand, if the stretching temperature is too high, the alignment obtained by the stretching may be eased by the temperature, and sufficient alignment may not be obtained. The extension step can be performed simultaneously with the amide imidization step. In terms of improving the surface hardness of the polyimide film, it is preferable to make the rate of imidate 80% or more, further 90% or more, further 95% or more, especially after substantially 100% imidateization. After imidization, the coating film is extended.

The stretch ratio of the polyimide film is preferably 101% or more and 10000% or less, and more preferably 101% or more and 500% or less. By extending within the above range, the surface hardness of the obtained polyimide film can be further increased.

The method of fixing the polyimide film during stretching is not particularly limited, and is selected according to the type of stretching device and the like. In addition, the stretching method is not particularly limited. For example, an stretching device having a conveying device such as a tenter can be used, and the stretching can be performed while passing through the heating furnace. The polyimide film can be extended in only one direction (longitudinal extension or horizontal extension), or it can be extended in two directions by simultaneous biaxial extension, or sequential biaxial extension, oblique extension, and the like.

<Second manufacturing method> In addition, regarding the method for manufacturing the polyimide film of the present invention, as the second manufacturing method, a method for manufacturing the polyimide film including the following steps may be mentioned: Preparing a polyimide resin composition containing polyimide and an organic solvent (hereinafter referred to as the preparation step of the polyimide resin composition); and The step of applying the polyimide resin composition to the support and drying and removing the solvent to form a polyimide resin coating film (hereinafter referred to as a polyimide resin coating film forming step).

In the case where the above-mentioned polyimide dissolves well in an organic solvent, a polymer in which the above-mentioned polyimide but not a polyimide precursor resin composition is dissolved in an organic solvent and contains additives as necessary may also be suitably used. Acetylene imide resin composition. When the above-mentioned polyimide has a solvent solubility of 5 mass% or more dissolved in an organic solvent at 25° C., this production method can be suitably used. Furthermore, in the present invention, the polyimide used in the production of the polyimide film is sometimes referred to as a polyimide material. The polyimide material may contain polyimide with a residual solvent below a specific amount.

In the second method for producing a polyimide film of the present invention, it is preferable to further have the following step: before the step of preparing the above polyimide resin composition, the polyimide used (polyamide) is measured Amine materials), determine whether the content of the organic solvent with a boiling point of 1 atm or less than 100°C is below 2000 ppm and the content of organic solvent with a boiling point of 1 atm and above 100°C is below 100 ppm. When the residual solvent amount of the polyimide (polyimide material) used exceeds the value specified in the present invention, it is preferable to further include the following steps: use the following washing steps to The amount of residual solvent in polyimide (polyimide material) is reduced below the value specified in the present invention. Furthermore, the polyimide used in the step of preparing the above polyimide resin composition is preferably a polyimide material having the structure represented by the above general formula (1), as a residual solvent, at 1 atmosphere The content of the organic solvent having a boiling point of not more than 100°C is 2000 ppm or less, and the content of the organic solvent having a boiling point of 1 atmosphere at 100°C or more is 100 ppm or less. In the polyimide material, in terms of improving static bending resistance and dynamic bending resistance, the content of the organic solvent having a boiling point of less than 100°C is also preferably 1000 ppm or less, more preferably 400 ppm or less, and It is preferably 100 ppm or less. On the other hand, in terms of improving the dynamic bending resistance, the content of the organic solvent having a boiling point of 100° C. or higher is preferably 80 ppm or lower, more preferably 50 ppm or lower, further preferably 30 ppm or lower, and still more preferably Below 20 ppm. In the polyimide material, the content of the organic solvent with a boiling point of 1 atm and a temperature below 70°C is 2000 ppm or less and the content of the organic solvent with a boiling point of 1 atm and a temperature above 70°C is 100 ppm or less. The content of the organic solvent with a boiling point of atmospheric pressure below 60°C is 2000 ppm or less and the content of an organic solvent with a boiling point of 1 atmospheric pressure exceeding 60°C is below 100 ppm. Furthermore, the boiling point of 1 atmospheric pressure may be below 50°C The content of the organic solvent is 2000 ppm or less and the content of the organic solvent having a boiling point of more than 50°C at 1 atmosphere is 100 ppm or less. In addition, in the second method for manufacturing a polyimide film of the present invention, it is also preferable to further have the step of measuring the amount of residual solvent in the obtained polyimide film to determine whether it is used as a residual solvent in the film, The content of the organic solvent with a boiling point of 1 atmosphere at a temperature below 100°C is 2000 ppm or less and the content of an organic solvent with a boiling point of 1 atmosphere at a temperature of 100°C or above is 100 ppm or less. When the amount of residual solvent of the obtained polyimide film exceeds the value specified in the present invention, it is preferable to further remove the residual solvent of the polyimide film by further performing the step of heating the polyimide film The amount is set below the value specified in the present invention.

In the preparation step of the polyimide resin composition, the polyimide can be selected from the same polyimides as described in the polyimide film and can be used with the polyimide having the solvent solubility. . As a method of imidization, it is preferable to use chemical imidization using a chemical imidization agent instead of heat dehydration for the dehydration ring-closure reaction of the polyimide precursor. In the case of chemical imidization, amines such as pyridine or β-picolinic acid, carbodiimides such as dicyclohexylcarbodiimide, and acid anhydrides such as acetic anhydride can also be used as dehydration catalysts. Compound. The acid anhydride is not limited to acetic anhydride, and examples thereof include propionic anhydride, n-butyric anhydride, benzoic anhydride, and trifluoroacetic anhydride, but are not particularly limited. In this case, tertiary amines such as pyridine and β-picolinic acid may be used in combination. However, if these amines remain in the film, the optical properties, especially yellowness (YI value) are reduced. Therefore, it is preferable to purify by reprecipitation and the like, and separate the components other than polyimide After the film is removed until it becomes less than 100 ppm of the total weight of the polyimide, the film is formed instead of directly casting the reaction solution obtained by reacting the polyimide precursor into the polyimide to form the film.

In the step of preparing the polyimide resin composition, as the organic solvent used as the reaction solution for chemical imidization of the polyimide precursor, for example, the above-mentioned polyimide in the first production method can be used The organic solvent described in the preparation step of the amine precursor resin composition is the same.

In addition, as the organic solvent used when the reaction liquid obtained by reacting into polyimide is purified by reprecipitation, etc., as long as the reaction liquid obtained by self-reaction of polyimide into polyimide is selected appropriately, The poor solvent of the precipitated polyimide and the good solvent of the polyimide used to dilute the reaction solution if necessary can be used together. The solid content concentration of the reaction solution (polyimide solution) when the poor solvent is added dropwise in order to precipitate polyimide is preferred in terms of productivity and efficient removal of impurities. It is 0.1% by mass or more and 30% by mass or less, and more preferably 1% by mass or more and 10% by mass or less. In order to make the solid component concentration of the above-mentioned polyimide solution suitable for precipitation of polyimide, a suitable good solvent of polyimide can also be used for dilution. In addition, a good solvent for polyimide can be appropriately selected and used from solvents having a solubility of polyimide at 25°C of 20 g/100 g or more as a standard. In addition, the poor solvent of polyimide can be appropriately selected and used from solvents whose solubility of polyimide is less than 20 g/100 g at 25°C as a standard.

For example, an organic solvent such as n-butyl acetate, which is a good solvent for polyimide, is added to the reaction solution obtained by reacting to polyimide and stirred until it becomes homogeneous to dilute the reaction solution, followed by slowly adding the third butyl Alcohol-based organic solvents such as alcohol, methanol, ethanol, isopropanol, 2-butanol, cyclohexanol, and tert-amyl alcohol precipitate polyimide to obtain a white slurry, which is filtered to obtain polyimide Imine. Among the above-mentioned alcohol-based organic solvents, in terms of excellent stability of polyimide, it is preferable to use secondary or tertiary alcohols, and it is more preferable to use tertiary alcohols. The polyimide obtained by reprecipitation as described above preferably measures the amount of residual solvent. The residual solvent amount of the polyimide can be measured in the same manner as the above method for determining the residual solvent amount of the polyimide film by using polyimide instead of the polyimide film. Furthermore, when measuring the residual solvent amount of polyimide (polyimide material), the polyimide (polyimide material) is dried using a vacuum dryer at 100°C to 120°C. The drying time may be appropriately adjusted according to the amount of polyimide (polyimide material). For example, in the case of polyimide (polyimide material) with a solid content of 100 g, drying is performed for about 3 hours, and in the case of insufficient drying, the drying time is appropriately added in units of 1 hour. Drying of polyimide (polyimide material) using a vacuum dryer can set the mass change of polyimide (polyimide material) before and after drying to 0.1 mass% or less as a standard.

The polyimide obtained by reprecipitation as described above is preferably further subjected to a washing step using an organic solvent to remove the residual solvent. For example, the polyimide obtained by reprecipitation is washed repeatedly in a beaker containing an organic solvent for washing, and then the washing step of filtration is performed, and the drying is performed at 100°C to 120°C using a vacuum dryer To obtain polyimide (polyimide material). As an organic solvent for washing, it has high compatibility with residual solvents contained in polyimide obtained by reprecipitation, and is a poor solvent for polyimide, and if a vacuum dryer is used at 100°C~ Drying at 120°C allows selection of all volatile organic solvents with boiling points less than the drying temperature of the vacuum dryer. For example, when the residual solvent is N,N-dimethylacetamide, N-methyl-2-pyrrolidone, etc. used in the preparation of the polyimide precursor, isopropanol, Methanol and the like are used as organic solvents for cleaning. One or more organic solvents for washing can be used. As described above, the polyimide obtained after the washing step is preferably used to measure the amount of residual solvent to determine whether it is below the value specified in the present invention. In the case of exceeding the value specified in the present invention, it further includes the use of The washing step is a step of reducing the residual solvent amount of the polyimide (polyimide material) used below the value specified in the present invention. In this way, a polyimide with a content of less than 2000 ppm of an organic solvent having a boiling point of less than 100°C and a content of an organic solvent with a boiling point of more than 100°C of less than 100 ppm can be obtained for preparing the above-mentioned polyimide resin composition (Polyimide material).

The polyimide material used to prepare the above polyimide resin composition is preferably polyimide powder. The average particle size of the polyimide powder is in terms of ease of handling as a powder. It is preferably 50 μm to 1000 μm, and more preferably 100 μm to 500 μm. In addition, regarding the average particle size of the polyimide material (polyimide powder) in the present invention, the polyimide material (polyimide powder) is used with an optical microscope (digital microscope VHX manufactured by KEYENCE) -5000) Observe at a magnification of 100 times, randomly extract 150 particles of polyimide material from the observation image, measure the particle size of each extracted particle, and calculate the average value. In addition, when the particle shape of the polyimide material is not spherical, the major axis is measured.

In the preparation step of the polyimide resin composition, examples of the organic solvent used for re-dissolving the polyimide (polyimide material) purified from the reaction solution include, for example, ethylene glycol monoethyl ether, Ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-butyl ether, ethylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, o-dichlorobenzene, xylene, cresol, chlorobenzene, ethyl acetate, Isobutyl acetate, isoamyl acetate, n-butyl acetate, n-propyl acetate, n-pentyl acetate, cyclohexanol, cyclohexanone, 1,4-dioxane, tetrachloroethylene, toluene, methyl iso Butyl ketone, methyl cyclohexanol, methyl cyclohexanone, methyl n-butyl ketone, dichloromethane, dichloroethane, chloroform, tetrahydrofuran, and mixed solvents of these. In the case of coating under the environment of an open system in the following polyimide resin coating film forming step, in terms of easily reducing the amount of residual solvent, the organic solvent for re-dissolving polyimide is preferable It is at least one selected from the group consisting of n-butyl acetate, ethyl acetate, and propylene glycol monomethyl ether acetate. In the following polyimide resin coating film forming step, in particular, in terms of easily reducing the amount of residual solvent during film manufacturing, the organic solvent for re-dissolving the polyimide is preferably used with a boiling point of less than 100°C As the organic solvent, it is particularly preferable to use an organic solvent having a boiling point of 70°C or lower. When using an organic solvent with a boiling point of less than 100°C, especially an organic solvent with a boiling point of 70°C or less, even when coating is performed in a closed system environment, it is easy to reduce the amount of residual solvent. Among them, in terms of easily reducing the amount of residual solvent and facilitating the film-forming step such as the drying step, preferably selected from dichloromethane, ethyl acetate, chloroform, tetrahydrofuran, n-butyl acetate, and propylene glycol monomethyl At least one of the groups consisting of ether acetate, especially in terms of easily reducing the amount of residual solvent and conducive to the film-forming step such as the drying step, can be preferably selected from dichloromethane, chloroform, tetrahydrofuran, and At least one of the group consisting of ethyl acetate.

The above-mentioned polyimide resin composition may contain additives as needed. As the above-mentioned additives, those same as those described in the step of preparing the above-mentioned polyimide precursor resin composition in the first production method can be used. In the second production method, as the method for setting the moisture content of the polyimide resin composition to 1000 ppm or less, and the method for dispersing the inorganic particles in an organic solvent, the method described above can be used. In the manufacturing method, the method described in the preparation step of the polyimide precursor resin composition described above is the same method.

In addition, in the polyimide resin coating film forming step in the second manufacturing method, the support or coating method may be the same as that described in the polyimide precursor resin coating film forming step in the first manufacturing method. The support or coating method is the same.

The drying step in the polyimide resin coating film forming step of the above second manufacturing method can be the same as the drying step described in the polyimide precursor resin coating film forming step of the above first manufacturing method, and the In the amination step, the heating step is carried out in the same manner. That is, first, the solvent in the polyimide resin composition on the support is dried in the same manner as the drying step of the polyimide precursor resin coating film forming step of the first manufacturing method described above, and then the polyimide resin is dried After the coating film is peeled off from the support, it is further dried, and it is preferable to have the above-mentioned steps in order to improve the bending resistance by setting the residual solvent amount of the polyimide film to a value specified below in the present invention. The temperature at which the polyimide resin coating film is dried after peeling off from the support does not need to be as high as the heating temperature of the imimidization in the first manufacturing method, as long as it depends on the organic solvent or residue used in the formation of the coating film The type or amount of the solvent can be adjusted appropriately. At normal pressure, it is preferably set to a range of 80° C. or more and 250° C. or less, and more preferably a range of 100° C. or more and 220° C. or less. Under reduced pressure, it is preferably in the range of 10°C or more and 200°C or less, and more preferably in the range of 30°C or more and 160°C or less. The drying time may be appropriately adjusted according to the amount of the organic solvent or residual solvent used when forming the coating film, and it is usually preferably 2 minutes to 60 minutes, and preferably 5 minutes to 40 minutes. When the upper limit value is exceeded, the production efficiency of the polyimide film is poor. On the other hand, when the value is lower than the lower limit, there is a possibility that the residual solvent may not be sufficiently reduced, and further, the appearance of the polyimide film obtained due to rapid solvent drying may be affected. In addition, in the step of further drying after peeling off from the support, in terms of preventing shrinkage during heating, it is preferable to fix the end of the polyimide resin coating film after peeling off from the support before drying . As a method of fixing the end of the polyimide resin coating film after being peeled off from the support, it can be carried out in the same manner as the above-mentioned polyimide precursor resin coating film.

In addition, the second manufacturing method may further include an extension step of extending the polyimide resin coating film after the polyimide resin coating film formation step. This stretching step can be performed in the same manner as the stretching step in the first manufacturing method described above.

The second manufacturing method described above is preferable in that it is easy to reduce the yellowness (YI value) of the polyimide film. According to the second manufacturing method described above, a polyimide film having a value of 0.04 or less obtained by dividing the yellowness calculated according to JIS K7373-2006 by the film thickness (μm) can be formed appropriately.

10. Use of Polyimide Film The use of the polyimide film of the present invention is not particularly limited, and it can be used as a base member or surface material of glass products such as thin plate glass, which are conventionally used. Since the polyimide film of the present invention has improved bending resistance and has sufficient surface hardness as a protective film, and optical strain can be reduced, it can be particularly suitably used as a member for a display that can handle curved surfaces. Specifically, the polyimide film of the present invention can be suitably used for, for example, thin and bendable flexible organic EL displays, mobile terminals such as smartphones or watch-type terminals, display devices in automobiles, watches, etc. Used as a substrate or surface material for flexible displays such as flexible panels. In addition, the polyimide film of the present invention can also be applied to components for image display devices such as liquid crystal display devices and organic EL display devices, components for touch panels, flexible printed substrates, surface protective films, substrate materials, etc. Components for solar cell panels, components for optical waveguides, other semiconductor-related components, etc.

III. Laminate The layered system of the present invention has the above-mentioned polyimide film of the present invention and a hard coat layer containing at least one polymer of a radically polymerizable compound and a cationic polymerizable compound. The laminate of the present invention uses the above-mentioned polyimide film of the present invention, and therefore has excellent transparency and improved bending resistance. Since it further has a hard coat layer, it is a film or a resin film whose surface hardness is further improved.

In addition, in the laminate of the present invention, since the polyimide contained in the polyimide film is contained in the diamine residue having a silicon atom in the main chain, it is excellent in the adhesion between the polyimide film and the hard coat layer. It is better. The reason for this is presumed to be that the specific polyimide film described above is excellent in compatibility with the hard coat layer. In addition, in the laminate of the present invention, the polyimide contained in the polyimide film is contained in the diamine residue having a silicon atom in the main chain, so it is preferable in terms of reducing optical strain. In this case, when the layered product of the present invention is used as a display surface material, a substrate, or other display member, the decrease in display quality of the display can be suppressed.

1. Polyimide film As the polyimide film used in the laminate of the present invention, the above-described polyimide film of the present invention can be used, so the description is omitted here.

2. Hard coating The hard coat layer used in the laminate of the present invention contains at least one polymer of a radically polymerizable compound and a cationically polymerizable compound.

(1) Radical polymerizable compounds The radical polymerizable compound is a compound having a radical polymerizable group. The radical polymerizable group possessed by the radical polymerizable compound is not particularly limited as long as it is a functional group capable of generating a radical polymerization reaction, and examples thereof include a group containing a carbon-carbon unsaturated double bond, and the like. Specifically, a vinyl group, (meth)acryloyl group, etc. are mentioned. Furthermore, in the case where the above radical polymerizable compound has two or more radical polymerizable groups, the radical polymerizable groups may be the same or different.

The number of radical polymerizable groups contained in one molecule of the radical polymerizable compound is preferably 2 or more, and more preferably 3 or more in terms of increasing the hardness of the hard coat layer. As the above-mentioned radically polymerizable compound, in terms of high reactivity, a compound having a (meth)acryloyl group is preferable, and 2 to 6 (methyl) groups in one molecule can be preferably used There are several compounds in the molecule of acryloyl called multifunctional acrylate monomers or amine (meth)acrylate, polyester (meth)acrylate, epoxy (meth)acrylate (Meth) acrylamides are oligomers with a molecular weight of hundreds to thousands. In addition, in this specification, (meth)acryloyl means each of acryl and methacryl, and (meth)acrylate means each of acrylate and methacrylate.

Specific examples of the radical polymerizable compound include vinyl compounds such as divinylbenzene; ethylene glycol di(meth)acrylate, bisphenol A epoxy di(meth)acrylate, 9 ,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl] stilbene, alkylene oxide modified bisphenol A di(meth)acrylate (eg ethoxylated (cyclic Oxyethane modification) bisphenol A di(meth)acrylate, etc.), trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, neopentyl alcohol Tri (meth) acrylate, neopentaerythritol tetra (meth) acrylate, di neopentaerythritol tri (meth) acrylate, di neopentaerythritol tetra (meth) acrylate, di neopentaerythritol Polyol polyacrylates such as alcohol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, bisphenol A diglycidyl ether diacrylate, hexanediol diglycidyl ether two Epoxy acrylates such as acrylates, amine acrylates obtained by the reaction of polyisocyanates and hydroxy-containing acrylates such as hydroxyethyl acrylate, etc.

(2) Cationic polymerizable compound The cationic polymerizable compound refers to a compound having a cationic polymerizable group. The cationic polymerizable group possessed by the cationic polymerizable compound is not particularly limited as long as it is a functional group capable of generating a cationic polymerization reaction, and examples thereof include epoxy groups, oxetanyl groups, and vinyl ether groups. . Furthermore, when the above-mentioned cationic polymerizable compound has two or more cationic polymerizable groups, the cationic polymerizable groups may be the same or different.

In terms of increasing the hardness of the hard coat layer, the number of cationic polymerizable groups that the cationic polymerizable compound has in one molecule is preferably 2 or more, and more preferably 3 or more. The cationic polymerizable compound is preferably a compound having at least one epoxy group and oxetanyl group as a cationic polymerizable group, in terms of adhesiveness, light transmittance, and surface hardness. It is more preferably a compound having at least one of two or more epoxy groups and oxetanyl groups in one molecule. In view of the small shrinkage accompanying the polymerization reaction, cyclic ether groups such as epoxy groups and oxetanyl groups are preferred. In addition, the compound having an epoxy group in a cyclic ether group has a compound with easy access to various structures, does not adversely affect the durability of the obtained hard coat layer, and is easy to control the compatibility with the radical polymerizable compound The advantages. In addition, the oxetanyl group in the cyclic ether group has the following advantages over the epoxy group: the degree of polymerization is higher and the toxicity is low. When the obtained hard coat layer is combined with the compound having an epoxy group, Accelerate the network formation speed obtained from the cationic polymerizable compound in the coating film. Even in the area mixed with the radical polymerizable compound, unreacted monomers will not remain in the film to form an independent network.

Examples of the cationic polymerizable compound having an epoxy group include the use of hydrogen peroxide and peroxide by using a polyglycidyl ether of a polyol having an alicyclic ring or a compound containing a cyclohexene ring and a cyclopentene ring. Cycloaliphatic epoxy resin obtained by epoxidation of an appropriate oxidizing agent such as acid; polyglycidyl ether of aliphatic polyhydric alcohol or its alkylene oxide adduct, polyglycidyl ester of aliphatic long-chain polybasic acid, (A Aliphatic epoxy resins such as homopolymers and copolymers of glycidyl acrylate; by bisphenols such as bisphenol A, bisphenol F or hydrogenated bisphenol A, or alkylene oxide adducts such as Glycidyl ethers produced by the reaction of derivatives such as caprolactone adducts with epichlorohydrin; and glycidyl ether epoxy resins derived from bisphenols such as novolac epoxy resins.

Examples of the alicyclic epoxy resin include 3,4-epoxycyclohexanecarboxylic acid 3,4-epoxycyclohexyl methyl ester (UVR-6105, UVR-6107, UVR-6110), and adipic acid. Bis(3,4-epoxycyclohexylmethyl) ester (UVR-6128) (above, trade names in parentheses, manufactured by Dow Chemical).

Moreover, as said glycidyl ether type epoxy resin, a sorbitol polyglycidyl ether (Denacol EX-611, Denacol EX-612, Denacol EX-614, Denacol EX-614B, Denacol EX-622), poly Glycerin polyglycidyl ether (Denacol EX-512, Denacol EX-521), neopentaerythritol polyglycidyl ether (Denacol EX-411), diglycerin polyglycidyl ether (Denacol EX-421), glycerol polyglycidyl ether (Denacol EX-313, Denacol EX-314), trimethylolpropane polyglycidyl ether (Denacol EX-321), resorcinol diglycidyl ether (Denacol EX-201), neopentyl glycol diglycidyl Ether (Denacol EX-211), 1,6-hexanediol diglycidyl ether (Denacol EX-212), hydrogen bisphenol A diglycidyl ether (Denacol EX-252), ethylene glycol diglycidyl ether ( Denacol EX-810, Denacol EX-811), polyethylene glycol diglycidyl ether (Denacol EX-850, Denacol EX-851, Denacol EX-821), propylene glycol glycidyl ether (Denacol EX-911), polypropylene glycol shrink Glycerol ether (Denacol EX-941, Denacol EX-920), allyl glycidyl ether (Denacol EX-111), 2-ethylhexyl glycidyl ether (Denacol EX-121), phenyl glycidyl ether (Denacol EX -141), phenol glycidyl ether (Denacol EX-145), butyl phenyl glycidyl ether (Denacol EX-146), phthalic acid diglycidyl ester (Denacol EX-721), hydroquinone diglycidyl ether (Denacol EX-203), terephthalic acid diglycidyl ester (Denacol EX-711), glycidyl phthalimide (Denacol EX-731), dibromophenyl glycidyl ether (Denacol EX- 147). Dibromo neopentyl glycol diglycidyl ether (Denacol EX-221) (above, the brand name in parentheses, manufactured by Nagase chemteX).

In addition, examples of epoxy resins of other commercially available products include: Epikote 825, Epikote 827, Epikote 828, Epikote 828EL, Epikote 828XA, Epikote 834, Epikote 801, Epikote 801P, Epikote 802, Epikote 815, Epikote 815XA Epikote 816A, Epikote 819, Epikote 834X90, Epikote 1001B80, Epikote 1001X70, Epikote 1001X75, Epikote 1001T75, Epikote 806, Epikote 806P, Epikote 807, Epikote 152, Epikote 871, Epikote 154, Epikote 154, Epikote 154, Epikote 154 , Epikote YX8034, etc. (the above are trade names, manufactured by Japan Epoxy Resins).

Examples of the cationic polymerizable compound having oxetanyl group include 3-ethyl-3-hydroxymethyloxetane (OXT-101) and 1,4-bis-3-ethyloxa Cyclobutane-3-ylmethoxymethylbenzene (OXT-121), bis-1-ethyl-3-oxetanyl methyl ether (OXT-221), 3-ethyl-3-2-ethyl Hexyloxymethyl oxetane (OXT-212), 3-ethyl-3-phenoxymethyl oxetane (OXT-211) (above, the product name in parentheses is East Asian synthesis Manufacturing), or trade names Etanacol EHO, Etanacol OXBP, Etanacol OXTP, Etanacol OXMA (the above are trade names, manufactured by Ube Industries).

(3) Polymerization initiator The at least one polymer of the radical polymerizable compound and the cationic polymerizable compound contained in the hard coat layer used in the present invention can be added as necessary in at least one of the radical polymerizable compound and the cationic polymerizable compound, for example. The polymerization initiator is obtained by performing a polymerization reaction by a known method.

As the above-mentioned polymerization initiator, a radical polymerization initiator, a cationic polymerization initiator, a radical, a cationic polymerization initiator and the like can be appropriately selected and used. The polymerization initiators are decomposed by at least one of light irradiation and heating to generate free radicals or cations to perform free radical polymerization and cation polymerization.

衍生物等，更具體而言，可列舉：1,3-二(第三丁基二氧基羰基)二苯甲酮、3,3',4,4'-四(第三丁基二氧基羰基)二苯甲酮、3-苯基-5-異㗁唑啉酮、2-巰基苯并咪唑、雙(2,4,5-三苯基)咪唑、2,2-二甲氧基-1,2-二苯基乙烷-1-酮（商品名Irgacure 651，Ciba Japan股份有限公司製造）、1-羥基環己基苯基-酮（商品名Irgacure 184，Ciba Japan股份有限公司製造）、2-苄基-2-二甲基胺基-1-(4-嗎啉基苯基)-丁烷-1-酮（商品名Irgacure 369，Ciba Japan股份有限公司製造）、雙(η5-2,4-環戊二烯-1-基)^_ 雙(2,6-二氟-3-(1H-吡咯-1-基)苯基)鈦)（商品名Irgacure 784，Ciba Japan股份有限公司製造）等，但並不限定於該等。The radical polymerization initiator may be any substance that can release radical polymerization by at least one of light irradiation and heating. For example, examples of the photoradical polymerization initiator include imidazole derivatives, bisimidazole derivatives, N-arylglycine derivatives, organic azide compounds, titanocenes, aluminate complexes, Organic peroxide, N-alkoxypyridinium salt, 9-oxysulfur

Derivatives and the like, more specifically, 1,3-bis(t-butyldioxycarbonyl)benzophenone, 3,3',4,4'-tetra(t-butyldioxy Carbonyl) benzophenone, 3-phenyl-5-isoazolidinone, 2-mercaptobenzimidazole, bis(2,4,5-triphenyl)imidazole, 2,2-dimethoxy -1,2-Diphenylethane-1-one (trade name Irgacure 651, manufactured by Ciba Japan Co., Ltd.), 1-hydroxycyclohexylphenyl-ketone (trade name Irgacure 184, manufactured by Ciba Japan Co., Ltd.) , 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butane-1-one (trade name Irgacure 369, manufactured by Ciba Japan Co., Ltd.), bis(η5- 2,4-cyclopentadien-1-yl) ^_bis (2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl) titanium) (trade name Irgacure 784, Ciba Japan Co., Ltd. Manufacturing), etc., but not limited to such.

In addition to the above, commercially available products can also be used, and specific examples include Irgacure 907, Irgacure 379, Irgacure 819, Irgacure 127, Irgacure 500, Irgacure 754, Irgacure 250, Irgacure 1800, Irgacure manufactured by Ciba Japan Co., Ltd. 1870, Irgacure OXE01, DAROCUR TPO, DAROCUR 1173, Speedcure MBB, Speedcure PBZ, Speedcure ITX, Speedcure CTX, Speedcure EDB, Esacure ONE, Esacure KIP150, Esacure KTO46, manufactured by Nippon Kayaku Co., Ltd. KAYACURE DETX-S, KAYACURE CTX, KAYACURE BMS, KAYACURE DMBI, etc.

In addition, the cationic polymerization initiator should only be able to release the substance that starts cationic polymerization by at least one of light irradiation and heating. As the cationic polymerization initiator, there can be exemplified: sulfonate, amide imine sulfonate, dialkyl-4-hydroxyammonium salt, p-nitrobenzyl arylsulfonate, silanol-aluminum complex, ( η ⁶ -benzene) (η ⁵ -cyclopentadienyl) iron (II) and the like, more specifically, benzoin tosylate, 2,5-dinitrobenzyl tosylate, N -Tosyl phthalimide and the like, but not limited to these.

As those that can be used as both free radical polymerization initiators and cationic polymerization initiators, there can be exemplified: aromatic iodonium salts, aromatic cerium salts, aromatic diazonium salts, aromatic phosphonium salts, tri-ammonium compounds , Iron aromatic hydrocarbon complexes, etc. More specifically, there can be mentioned: Chlorine such as diphenylphosphonium, xylylphosphonium, bis(p-tertiary butylphenyl) iodide, bis(p-chlorophenyl) iodide, etc. Compound, bromide, fluoroborate, hexafluorophosphate, hexafluoroantimonate, and other iodide salts, triphenyl alkane, 4-third butyl triphenyl alkane, tri(4-methylphenyl) alkane, etc. Manganese chloride, bromide, fluoroborate, hexafluorophosphate, hexafluoroantimonate and other monium salts, 2,4,6-tris(trichloromethyl)-1,3,5-tris, 2 -Phenyl-4,6-bis(trichloromethyl)-1,3,5-tris, 2-methyl-4,6-bis(trichloromethyl)-1,3,5-tris 2,4,6-substituted-1,3,5 three compounds, etc., but not limited to these.

(4) Additives The hard coat layer used in the present invention may contain antistatic agents, anti-glare agents, anti-fouling agents, inorganic or organic fine particles for improving hardness, leveling agents, various sensitizers, etc., if necessary. additive.

In addition, at least one polymer such as a radical polymerizable compound and a cationic polymerizable compound contained in the hard coat layer used in the present invention can use a Fourier transform infrared spectrophotometer (FTIR) and a thermal decomposition gas chromatography device ( GC-MS), or use a combination of high-performance liquid chromatography, gas chromatography mass spectrometry, NMR, elemental analysis, XPS/ESCA and TOF-SIMS to analyze the decomposition products of the polymer.

3. Composition of laminate The laminate of the present invention is not particularly limited as long as it has the above-mentioned polyimide film and the above-mentioned hard coat layer, and may be one having the above-mentioned hard coat layer deposited on one side of the above-mentioned polyimide film, or The two areas of the polyimide film have the hard coating layer. In addition, the laminate of the present invention may be, in addition to the above-mentioned polyimide film and the above-mentioned hard coat layer, within the range that does not impair the effects of the present invention, for example, it may also have the above-mentioned polyimide film and the above-mentioned hard coat layer. The other layers such as the undercoat layer of the adhesiveness can also be obtained by other laminated layers such as the above-mentioned polyimide film and the above-mentioned hard coat layer interposing the undercoat layer. In addition, the laminate of the present invention may be one in which the polyimide film is present adjacent to the hard coat layer. In addition, the laminate of the present invention may further have an impact resistant layer, an anti-fingerprint adhesion layer, an adhesive layer or an adhesive layer.

The overall thickness of the layered product of the present invention may be appropriately selected according to the application, and in terms of strength, it is preferably 10 μm or more, and more preferably 40 μm or more. On the other hand, in terms of bending resistance, it is preferably 300 μm or less, and more preferably 250 μm or less. In addition, in the laminate of the present invention, the thickness of each hard coat layer may be appropriately selected according to the application, preferably 2 μm or more and 80 μm or less, more preferably 3 μm or more and 50 μm or less. In addition, from the viewpoint of preventing curling, a hard coat layer may be formed on both sides of the polyimide film.

4. Characteristics of laminate In the laminate of the present invention, the pencil hardness of the surface of the hard coat layer is preferably H or more, more preferably 2H or more, and still more preferably 3H or more. The pencil hardness of the laminate of the present invention can be measured in the same manner except that the load is set to 9.8 N in the above method for measuring the pencil hardness of the polyimide film.

The layered body of the present invention preferably has a total light transmittance measured in accordance with JIS K7361-1 of 85% or more, more preferably 88% or more, and still more preferably 90% or more. This has a high penetration rate, so the transparency becomes good and can be used as a substitute for glass. The total light transmittance of the laminate of the present invention can be measured in the same manner as the total light transmittance of the polyimide film measured in accordance with JIS K7361-1.

The laminated body of the present invention preferably has a yellowness (YI value) calculated according to JIS K7373-2006 of 20 or less, more preferably 15 or less, further preferably 10 or less, and particularly preferably 5 or less. In addition, in terms of suppressing the coloration of the yellow tone and improving the light transmittance, and being suitable for use as a glass substitute material, the layered body of the present invention preferably uses the yellowness (YI value calculated according to JIS K7373-2006 above) ) Divided by the film thickness (μm) (YI value/film thickness (μm)) is 0.10 or less, more preferably 0.04 or less, and even more preferably 0.03 or less. The yellowness (YI value) of the laminate of the present invention can be measured in the same manner as the yellowness (YI value) calculated according to JIS K7373-2006 of the polyimide film.

5. Purpose of the laminate The use of the laminate of the present invention is not particularly limited, and for example, it can be used for the same purpose as the above-mentioned polyimide film of the present invention.

6. Manufacturing method of laminate As a manufacturing method of the laminate of the present invention, for example, a manufacturing method including the following steps may be mentioned: Forming a coating film of a composition for forming a hard coat layer containing at least one of a radically polymerizable compound and a cationic polymerizable compound on at least one side of the polyimide film of the present invention; and The above coating film is hardened.

The composition for forming a hard coat layer contains at least one of a radically polymerizable compound and a cationically polymerizable compound, and may further contain a polymerization initiator, a solvent, an additive, etc., if necessary. Here, regarding the radical polymerizable compound, the cationic polymerizable compound, the polymerization initiator and the additives contained in the composition for forming the hard coat layer, the same ones as described in the above hard coat layer may be used, and the solvent may be It is appropriately selected from known solvents and used.

As a method for forming the coating film of the composition for forming the hard coat layer on at least one side of the polyimide film, for example, the hard coat layer may be coated on at least one side of the polyimide film by a known coating method. The method of forming the composition. The coating means is not particularly limited as long as it can be applied at a target film thickness, and examples thereof include the same as the means for applying the polyimide precursor resin composition to the support.

The coating film of the hardening resin composition for hard coat layers described above is dried to remove the solvent if necessary. As the drying method, for example, a method of drying under reduced pressure or heating, and further combining these drying methods, etc. may be mentioned. In addition, in the case of drying under normal pressure, it is preferable to perform drying at 30°C or higher and 110°C or lower.

The coating film obtained by applying the above hardening resin composition for hard coat layer and drying if necessary corresponds to the polymerizability of the radically polymerizable compound and the cationic polymerizable compound contained in the curable resin composition Based on at least any one of light irradiation and heating to harden the coating film, thereby forming a hard coating of at least one polymer containing a radically polymerizable compound and a cationic polymerizable compound on at least one side of the polyimide film Floor.

Light irradiation mainly uses ultraviolet rays, visible light, electron beams, free radiation, etc. In the case of ultraviolet curing, ultraviolet rays emitted from the light of ultra-high pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, carbon arcs, xenon arcs, metal halide lamps, etc. are used. The irradiation amount of the energy ray source is about 50 to 5000 mJ/cm ² based on the cumulative exposure of the ultraviolet wavelength of 365 nm. In the case of heating, the treatment is usually performed at a temperature of 40°C or higher and 120°C or lower. Alternatively, the reaction may be carried out by leaving it at room temperature (25°C) for more than 24 hours.

IV. Components for display The display member of the present invention includes the above-mentioned polyimide film of the present invention or the laminate of the present invention. Examples of the member for display of the present invention include a surface material for display and a base material for display. The display member of the present invention may be the above-mentioned polyimide film of the present invention or the laminate of the present invention.

The display member of the present invention is used, for example, as a surface material for a display so as to be located on the surface of various displays. Like the polyimide film of the present invention and the laminate of the present invention, the display member of the present invention has excellent transparency and improved bending resistance, and has sufficient surface hardness as a protective film, so it can be used particularly suitably Used as a flexible display.

The member for display of the present invention can be used for various known displays, and is not particularly limited. For example, it can be used for the display described in the above application of the polyimide film of the present invention.

Furthermore, in the case where the display member of the present invention is the laminate of the present invention described above, the surface which becomes the outermost surface after the laminate is disposed on the surface of the display may be the surface of the polyimide film side, or may be The surface of the hard coating side. Among them, it is preferable to arrange the display member of the present invention such that the surface on the hard coat side becomes the surface on the more front side. In addition, the display member of the present invention may be one having an anti-fingerprint adhesion layer on the outermost surface.

In addition, the method of arranging the member for display of the present invention on the surface of the display is not particularly limited, and examples thereof include a method via a bonding layer. As the above-mentioned adhesive layer, a conventionally known adhesive layer that can be used for adhesion of a member for a display can be used.

V. Touch panel components The touch panel member of the present invention includes: the polyimide film of the present invention described above or the laminate of the present invention described above; A transparent electrode, which is arranged on one side of the polyimide film or the laminate, and is composed of a plurality of conductive parts; and A plurality of lead wires are electrically connected to at least one side of the end of the conductive portion.

Since the touch panel member of the present invention includes the above-mentioned polyimide film or laminate of the present invention, it is excellent in bending resistance, so it can be particularly suitably used as a flexible display and has excellent optical characteristics. The laminate of the present invention used in the touch panel member of the present invention is preferably a hard coat layer having at least one polymer containing a radically polymerizable compound and a cationically polymerizable compound adjacent to both sides of the polyimide film . In addition, the touch panel member of the present invention is not particularly limited, but it is preferable that the transparent electrode is laminated in contact with one surface side of the laminate. The touch panel member of the present invention can be arranged and used, for example, on the surface of various displays. In addition, the touch panel member of the present invention and the polyimide film or laminate of the present invention as a surface material may be sequentially arranged on the surface of various displays.

Hereinafter, the touch panel member of the present invention will be described by using the above-described laminate of the present invention. However, the above-described polyimide film of the present invention can also be used in place of the above-mentioned laminate of the present invention. 2 is a schematic top view of one surface of an example of the touch panel member of the present invention, FIG. 3 is a schematic top view of the other surface of the touch panel member shown in FIG. 2, and FIG. 4 is a touch shown in FIGS. 2 and 3. AA' sectional view of the panel member. The touch panel member 20 shown in FIGS. 2, 3 and 4 includes: the layered body 10 of the present invention, the first transparent electrode 4 arranged in contact with one surface of the layered body 10, and contacted with the other surface of the layered body 10 The second transparent electrode 5 is configured. In the first transparent electrode 4, a plurality of first conductive portions 41 which are short strip-shaped electrode pieces extending so as to extend in the x-axis direction are arranged at specific intervals. To the first conductive portion 41, a first lead 7 electrically connected to the first conductive portion 41 is connected to any one of the ends in the longitudinal direction. A first terminal 71 for electrically connecting to an external circuit is preferably provided at the end of the first lead wire 7 extending to the end 21 of the laminate 10. Generally speaking, the first conductive portion 41 and the first lead wire 7 are connected in the ineffective area 23 located outside the effective area 22 that can be recognized by the user of the touch panel. For example, as shown in FIG. 2, the connection structure between the first conductive portion 41 and the first lead wire 7 may be a connection structure with a connection portion 24 interposed therebetween. Specifically, the connection portion 24 can be formed by extending the conductive material layer from the longitudinal end of the first conductive portion 41 to a specific position in the ineffective region 23. Furthermore, at least a part of the first lead-out wire 7 is overlapped on the connecting portion 24, whereby the connection structure of the first conductive portion 41 and the first lead-out wire 7 can be formed. The connection between the first conductive portion 41 and the first lead wire 7 is not limited to the structure in which the connecting portion 24 is formed as shown in FIG. 2. For example, although not shown in the figure, the lengthwise end of the first conductive portion 41 may be extended to the invalid region 23, and in the invalid region 23, the first lead 7 may be covered to the first extended to the invalid region 23 The end of the conductive portion 41 thereby electrically connects the two. In addition, FIG. 2 shows a form in which any one of the longitudinal end portions of the first conductive portion 41 is connected to the first lead wire 7, but in the present invention, it may be set to one first conductive portion The two ends of the length direction of 41 are electrically connected to the first lead 7 respectively.

As shown in FIG. 3, the touch panel member 20 includes a second transparent electrode 5 arranged in contact with the other surface of the laminate 10. In the second transparent electrode 5, a plurality of short strip-shaped electrode pieces extending in the y-axis direction, that is, the second conductive portions 51 are arranged at specific intervals in the x-axis direction. A second lead 8 electrically connected to the second conductive portion 51 is connected to one end of the second conductive portion 51 in the longitudinal direction. The second lead-out wire 8 extends to an end edge of the laminate 10 where the end edge 21 of the first lead-out wire 7 does not overlap the first terminal 71. A second terminal 81 for electrically connecting to an external circuit is preferably provided at the end of the second lead wire 8 extending to the end 21 of the laminate 10. The electrical connection between the second conductive portion 51 and the second lead wire 8 can be applied in the same manner as the electrical connection between the first lead wire 7 and the first conductive portion 41.

Furthermore, as shown in FIGS. 2 and 3, the pattern using the first lead 7 as a long wiring and the second lead 8 as a short wiring is only one embodiment of the touch panel member of the present invention. For example, a pattern may be used in which the first lead wire 7 is a short wiring and the second lead wire 8 is a long wiring. In addition, the extension direction of the first lead wire 7 and the extension direction of the second lead wire 8 are not limited to the directions shown in FIGS. 2 and 3 and can be designed arbitrarily.

The conductive portion provided in the touch panel member of the present invention can be appropriately selected and applied to those that form transparent electrodes in the touch panel member, and the pattern of the conductive portion is not limited to those shown in FIGS. 2 and 3. For example, a transparent electrode pattern that can sense a change in capacitance caused by contact with a finger or the like or a state close to the contact by an electrostatic capacitance method can be appropriately selected and applied. The material of the conductive portion is preferably a light-transmitting material, and examples thereof include indium oxide-based transparent electrode materials having indium tin oxide (ITO), indium oxide, indium zinc oxide (IZO), and the like as main constituents; Transparent conductive films such as tin (SnO ₂ ), zinc oxide (ZnO), etc. as main constituents; conductive polymer compounds such as polyaniline and polyacetylene, but not limited to these. In addition, the first conductive portion 41 and the second conductive portion 51 may be formed using the same kind of conductive materials, or may be formed using different types of materials. In particular, if the same conductive material is used to form the first conductive portion 41 and the second conductive portion 51, it is preferable from the viewpoint that the generation of warpage or strain of the touch panel member can be more effectively suppressed. The thickness of the conductive portion is not particularly limited. For example, when the conductive portion is formed by photolithography, it can generally be formed at about 10 nm to 500 nm.

The conductive material constituting the lead-out line provided in the touch panel member of the present invention may be transparent or not. Generally speaking, the lead-out wire can be formed using a metal material such as silver or copper with high conductivity. Specifically, a simple substance of a metal, a metal composite, a composite of a metal and a metal compound, and a metal alloy can be mentioned. As the elemental metal, elements such as silver, copper, gold, chromium, platinum, and aluminum can be exemplified. As the metal composite, MAM (three-layer structure of molybdenum, aluminum, and molybdenum) can be exemplified. As a composite of a metal and a metal compound, a laminate of chromium oxide and chromium can be exemplified. As the metal alloy, silver alloy or copper alloy is widely used. Moreover, as a metal alloy, APC (silver, palladium, and copper alloy) etc. are illustrated. In addition, with respect to the above-mentioned lead wire, a resin component may be appropriately mixed in the above-mentioned metal material. In the touch panel member of the present invention, the terminal provided at the end of the lead-out wire can be formed using the same material as the lead-out wire, for example. The thickness and width of the above-mentioned lead-out line are not particularly limited. For example, when the lead-out line is formed by a photo-etching method, generally, the thickness is about 10 nm to 1000 nm, and the width is 5 μm to 200 about μm. On the other hand, when the lead line is formed by printing such as screen printing, generally, the thickness is about 5 μm to 20 μm, and the width is about 20 μm to 300 μm.

The touch panel member of the present invention is not limited to the forms shown in FIGS. 2 to 4, for example, the first transparent electrode and the second transparent electrode may be stacked on different laminates. 5 and 6 are schematic plan views each showing an example of a conductive member provided with the laminate of the present invention. The first conductive member 201 shown in FIG. 5 has the layered body 10 of the present invention and a first transparent electrode 4 arranged in surface contact with the layered body 10, the first transparent electrode 4 having a plurality of first conductive portions 41. The second conductive member 202 shown in FIG. 6 has the layered body 10' of the present invention and a second transparent electrode 5 disposed in surface contact with the layered body 10'. The second transparent electrode 5 has a plurality of second Conductive part 51. 7 is a schematic cross-sectional view showing another example of the touch panel member of the present invention. The touch panel member 20' shown in FIG. 7 includes the first conductive member 201 shown in FIG. 5 and the second conductive member 201 shown in FIG. Conductive member 202. In the touch panel member 20 ′, the surface of the first conductive member 201 without the first transparent electrode 4 and the surface of the second conductive member 202 with the transparent electrode 5 are bonded via the adhesive layer 6. Furthermore, in the present invention, for example, as an adhesive layer for adhering the laminate of the present invention and the touch panel member of the present invention, an adhesive layer for adhering the touch panel members of the present invention to each other, for Adhesive layers such as touch panel components and display devices of the present invention can be used by appropriately selecting conventional and well-known adhesive layers used for optical components. In the conductive member used in the touch panel member of the present invention, the configuration and material of the transparent electrode, the lead wire and the terminal can be set to be the same as the transparent electrode, the lead wire and the terminal used in the above-mentioned touch panel member of the present invention the same.

VI. Liquid crystal display device The liquid crystal display device of the present invention includes the polyimide film of the present invention or the laminate of the present invention, and a liquid crystal display section, and the liquid crystal display section is disposed on one surface side of the polyimide film or the laminate body, and The liquid crystal layer is formed between the opposite substrates.

Since the liquid crystal display device of the present invention includes the polyimide film of the present invention or the laminate of the present invention, it has excellent bending resistance, is particularly suitable for flexible display applications, and has excellent optical characteristics. The laminate of the present invention used in the liquid crystal display device of the present invention is preferably a hard coat layer having at least one polymer containing a radical polymerizable compound and a cationic polymerizable compound adjacent to both sides of the polyimide film. In addition, the liquid crystal display device of the present invention may be one provided with the touch panel member of the present invention. In addition, the counter substrate included in the liquid crystal display device of the present invention may be a polyimide film or a laminate of the present invention.

Hereinafter, the liquid crystal display device of the present invention will be described by using the above-described layered product of the present invention. However, the above-described polyimide film of the present invention can also be used in place of the above-described layered product of the present invention. 8 is a schematic cross-sectional view showing an example of a liquid crystal display device of the present invention. The liquid crystal display device 100 shown in FIG. 8 has the laminated body 10 of the present invention, and the touch panel member 20 provided with the first transparent electrode 4 on one side and the second transparent electrode 5 on the other side 、和LCD Display 30. In the liquid crystal display device 100, the laminate 10 is used as a surface material, and the laminate 10 and the touch panel member 20 are bonded via the adhesive layer 6.

The liquid crystal display part used in the liquid crystal display device of the present invention has a liquid crystal layer formed between opposed substrates, and a structure used in a conventionally known liquid crystal display device can be adopted. The driving method of the liquid crystal display device of the present invention is not particularly limited. Generally, the driving method used for the liquid crystal display device can be adopted, and examples thereof include a TN method, an IPS method, an OCB method, and an MVA method. The counter substrate used in the liquid crystal display device of the present invention can be appropriately selected and used according to the driving method of the liquid crystal display device or the like, and those having the polyimide film or laminate of the present invention can also be used. As the liquid crystal constituting the liquid crystal layer, various liquid crystals having different dielectric anisotropies and mixtures thereof can be used according to the driving method of the liquid crystal display device of the present invention. As a method of forming the liquid crystal layer, a method generally used as a method of manufacturing a liquid crystal cell can be used, and examples thereof include a vacuum injection method and a liquid crystal dropping method. After the liquid crystal layer is formed by the above method, the enclosed liquid crystal can be aligned by slowly cooling the liquid crystal cell to normal temperature. In the liquid crystal display device of the present invention, a coloring layer of multiple colors may be further provided between the oppositely disposed substrates, or a light-shielding portion defining pixels. In addition, the liquid crystal display portion may have a backlight portion including a light-emitting element or a phosphor on a position opposite to the side where the touch panel member is present on the outside of the substrate disposed oppositely. Moreover, polarizing plates may be provided on the outer surfaces of the substrates that are oppositely arranged.

9 is a schematic cross-sectional view showing another example of the liquid crystal display device of the present invention. The liquid crystal display device 200 shown in FIG. 9 includes the layered body 10 of the present invention, the first conductive member 201 having the first transparent electrode 4 on one side of the layered body 10' of the present invention, and the layered body 10 of the present invention The touch panel member 20' having the second conductive member 202 of the second transparent electrode 5 on one side and the liquid crystal display unit 30. In the liquid crystal display device 200, the laminate 10 and the first conductive member 201, and the first conductive member 201 and the second conductive member 202 are bonded via the respective adhesive layers 6, respectively. The configuration of the touch panel member 20' may be the same as the configuration of the touch panel member 20' shown in FIG. 7, for example. As the conductive member used in the liquid crystal display device of the present invention, the same conductive member used in the touch panel member of the present invention can be used.

VII. Organic electroluminescence display device The organic electroluminescence display device of the present invention includes the above-described polyimide film of the present invention or the above-described laminate of the present invention, and an organic electroluminescence display portion, which is disposed on the polyimide film Or, it is formed on one surface side of the above-mentioned layered body and having an organic electroluminescent layer between the opposing substrates.

Since the organic electroluminescence display device of the present invention is provided with the polyimide film of the present invention or the laminate of the present invention, it is excellent in bending resistance, so it can be particularly suitably used as a flexible display, and Excellent optical properties. The laminate of the present invention used in the organic electroluminescence display device of the present invention preferably has a hard coating layer having at least one polymer containing a radically polymerizable compound and a cationic polymerizable compound adjacent to both sides of the polyimide film Layers. In addition, the organic electroluminescence display device of the present invention may also include the touch panel member of the present invention. In addition, the counter substrate included in the organic electroluminescence display device of the present invention may be a polyimide film or a laminate provided with the present invention.

10 is a schematic cross-sectional view showing an example of the organic electroluminescence display device of the present invention. The organic electroluminescent display device 300 shown in FIG. 10 includes: the laminated body 10 of the present invention, a touch including the first transparent electrode 4 on one surface of the laminated body 10' of the present invention and the second transparent electrode 5 on the other surface The panel member 20 and the organic electroluminescence display unit 40. In the organic electroluminescence display device 300, the layered body 10 is used as a surface material, and the layered body 10 and the touch panel member 20 are bonded via the adhesive layer 6.

The organic electroluminescence display part (organic EL display part) used in the organic electroluminescence display device (organic EL display device) of the present invention has an organic electroluminescence layer (organic EL layer) formed between opposed substrates ), it is possible to adopt the structure used in conventionally known organic EL display devices. The organic EL display unit may further include: a support substrate, an organic EL element including an organic EL layer and an anode layer and a cathode layer sandwiching the organic EL layer, and a sealing base material for sealing the organic EL element. The organic EL layer may be at least an organic EL light-emitting layer. For example, a positive hole injection layer, a positive hole transport layer, an organic EL light-emitting layer, and electrons may be stacked in this order from the anode layer side. Constructor of transport layer and electron injection layer. The organic EL display device of the present invention can be applied to, for example, an organic EL display of a passive driving method or an organic EL display of an active driving method. The counter substrate used in the organic EL display device of the present invention can be appropriately selected and used according to the driving method of the organic EL display device or the like, and a laminate provided with the present invention can also be used.

11 is a schematic cross-sectional view showing another example of the organic electroluminescence display device of the present invention. The organic electroluminescence display device 400 shown in FIG. 11 includes the layered body 10 of the present invention, the first conductive member 201 having the first transparent electrode 4 on one side of the layered body 10' of the present invention, and the The laminated body 10 ′ is provided with a touch panel member 20 ′ of the second conductive member 202 of the second transparent electrode 5 on one surface, and an organic electroluminescence display unit 40. In the organic electroluminescence display device 400, the laminate 10 and the first conductive member 201, the first conductive member 201 and the second conductive member 202 are bonded via the adhesive layer 6, respectively. The configuration of the touch panel member 20' may be the same as the configuration of the touch panel member 20' shown in FIG. 7, for example. As the conductive member used in the organic electroluminescence display device of the present invention, the same conductive member used in the touch panel member of the present invention can be used. Examples

[Evaluation method] In the following, unless otherwise specified, measurement or evaluation is performed at 25°C. The test piece of the film was cut out near the center of the film. Using the above film thickness measurement method, the film thickness of the four corners and the center of the cut film is measured at a total of 5 points, and the difference between the average film thickness at 5 points and the film thickness at each point is 6% of the average film thickness The test piece within.

<Weight average molecular weight of polyimide precursor> The weight average molecular weight of the polyimide precursor is to make the polyimide precursor into a 0.5% by weight concentration of N-methylpyrrolidone (NMP) solution, and pass the solution through a syringe filter (pore size: 0.45 μm ) Filtration, using a 10 mmol% LiBr-NMP solution with a water content of 500 ppm or less as a developing solvent, using a GPC device (HLC-8120 manufactured by Tosoh, using a column: GPC LF-804 manufactured by SHODEX), at the sample injection volume 50 μL, solvent flow rate 0.5 mL/min, and 40°C were measured. The weight average molecular weight of the polyimide precursor is based on the relative measurement of the polystyrene standard sample (weight average molecular weight: 364,700, 204,000, 103,500, 44,360, 27,500, 13,030, 6,300, 3,070) at the same concentration as the sample. Conversion value for standard polystyrene. The dissolution time is compared with the calibration curve to determine the weight average molecular weight. <Viscosity of polyimide precursor solution> The viscosity of the polyimide precursor solution was measured using a viscometer (eg TVE-22HT, Toki Industry Co., Ltd.) at 25°C with a sample volume of 0.8 ml.

<weight average molecular weight of polyimide> 15 mg of polyimide powder was immersed in 15000 mg of N-methylpyrrolidone (NMP), while being heated to 60°C in a water bath, and stirred for 3 to 60 hours using a stirrer at a rotation speed of 200 rpm until visual confirmation Upon dissolution, an NMP solution with a concentration of 0.1% by weight was obtained. The solution was filtered through a syringe filter (pore size: 0.45 μm), using a 30 mmol% LiBr-NMP solution with a water content of 500 ppm or less as a developing solvent, and using a GPC device (HLC-8120 manufactured by Tosoh, detector: differential) Refractive index (RID) detector, using column: two GPC LF-804 manufactured by SHODEX connected in series), sample injection volume 50 μL, solvent flow rate 0.4 mL/min, column temperature 37℃, detector temperature 37 Measure at ℃. The weight average molecular weight of polyimide is set based on the polystyrene standard samples with the same concentration as the sample (weight average molecular weight 364,700, 204,000, 103,500, 44,360, 27,500, 13,030, 6,300, 3,070) relative to the standard polybenzene Conversion value of ethylene. The dissolution time is compared with the calibration curve to determine the weight average molecular weight. <Viscosity of Polyimide Solution> The viscosity of the polyimide solution is measured using a viscometer (eg TVE-22HT, Toki Industry Co., Ltd.) at 25°C with a sample volume of 0.8 ml.

<Average particle size of polyimide material (polyimide powder)> Observe the polyimide material (polyimide powder) with an optical microscope (digital microscope VHX-5000 manufactured by KEYENCE) at a magnification of 100 times, and randomly extract 150 particles of polyimide material from its observation image Measure each particle size of the extracted particles, calculate the average value, and set it as the average particle size of the polyimide material. Furthermore, when the particle shape of the polyimide material is not spherical, the long diameter is measured.

<Remaining amount of solvent in polyimide film> After specifying the type of residual solvent in the polyimide film, the content of the specific residual solvent is quantified. [Specification of residual solvent type] Use a GC-MS connected to a purge & trap device (heat desorption device) to specify the type of residual solvent. A sample tube equipped with a polyimide film 10 mg was installed in a purging & trapping device (product name JTD505-III, Japan Analytical Industries Co., Ltd.), which was heated at 200°C for 30 minutes to heat it. The gas is collected by a collection tube at -60°C, the trapped person is heated at 315°C and scattered, and sent to GC-MS to qualitatively analyze the composition of the generated organic gas. (Conditions of Purge & Capture Device) Total split ratio (introduction/exhaust) 1:10, Carrier gas helium 1.0 ml/min (GC-MS conditions) Device name: GC-MS device (Agilent, 6890/5973 GC/MS) Column: UA-5 inner diameter 250 μm × length 30 m × film thickness 0.25 μm (manufactured by Frontier Laboratories), heating conditions 50℃ (hold 5 minutes) → 10℃/min (heating) → 320℃ (hold 3 minutes) [Quantification of residual solvent] Polyimide film was added to N,N-dimethylformamide (DMF) so that the concentration of the polyimide film became 5 mass% to prepare a polyimide film/N,N-dimethyl A methylformamide (DMF) solution, and an internal standard solution (0.2% by mass concentration anisole/DMF solution) was added to the solution to prepare a sample solution. Using a GC-MS apparatus (for example, Agilent Corporation, 6890/5973 GC/MS), the sample solution was subjected to GC-MS measurement under the following conditions. This GC-MS measurement was performed three times, and the measurement result was set as the average of three times. (GC conditions) Column: InertCapWax inner diameter 250 μm × length 30 m × film thickness 0.25 mm (manufactured by GL Science), Sample injection volume 0.2 μL, split ratio 50:1, carrier gas is helium 94.3 kPa constant pressure, injection port temperature 250℃, heating condition 40℃ (hold 5 minutes)→5℃/min→120℃→20℃/min →240℃ (maintain for 6 minutes), conveyor line temperature 250℃ (MS conditions) Ionization method EI, measurement mode SIM, ion source temperature 250℃, quadrupole temperature 150℃, ionization voltage 70 eV (Quantitative ion) DMAc m/z = 72, 87 Methylene chloride m/z = 49, 84 Ethyl acetate m/z = 43, 88 Butyl acetate m/z = 43, 56, 73 PGMEA m/z =45, 90 Anisole m/z = 93, 108

For example, when the residual solvent is DMAc, each DMAc (measurement target compound)/DMF solution prepared with the DMAc content of 0.01% by mass, 0.05% by mass, and 0.1% by mass is added in the same manner as the above sample solution. Each calibration curve liquid is prepared from the standard solution, and GC-MS measurement is performed on each calibration curve liquid to prepare a calibration curve. In addition, GC-MS measurement was performed 3 times, and the measurement result was set as the average value of 3 times. Then, based on the calibration curve, the content of DMAc is calculated as a mass ratio with respect to the polyimide film. When there are more than two kinds of residual solvents, a calibration curve liquid is prepared for each residual solvent by the above-mentioned DMAc method, GC-MS measurement is performed on each calibration curve liquid, a calibration curve is prepared based on the measurement results, and the The calibration curve is the reference.

<Residual solvent content of polyimide material> The amount of residual solvent in the polyimide material is the same as the above method for determining the amount of residual solvent in the polyimide film, using a polyimide material instead of the polyimide film.

<Full light transmittance of polyimide film> According to JIS K7361-1, the measurement was performed with a haze meter (HM150 manufactured by Murakami Color Technology Research Institute).

2 mm，靜置24小時）＞ 以下，參照圖1對靜態彎曲試驗之方法進行說明。 將切成15 mm×40 mm之聚醯亞胺膜之試片1以長邊之一半位置進行彎折，以試片1之長邊之兩端部自上下面夾著厚度2 mm之金屬片2（100 mm×30 mm×2 mm）之方式進行配置，且以試片1之兩端部與金屬片2之上下面中之重疊區域分別成為10 mm之方式利用膠帶進行固定。利用玻璃板（100 mm×100 mm×0.7 mm）3a、3b自上下夾住固定有試片1之金屬片2，而將試片1於以內徑2 mm彎曲之狀態固定。此時，於在金屬片2上不存在試片1之部分中夾入虛設試片4a、4b，以玻璃板3a、3b成為平行之方式利用膠帶進行固定。 將如此以彎曲之狀態所固定之試片於60±2℃、93±2%相對濕度（RH）之環境靜置24小時後，將玻璃板與試片固定用膠帶剝離，而解除對試片施加之力。其後，將試片之一端部固定，於解除對試片施加之力後經過30分鐘後測定試片之內角。 再者，於膜未受該靜態彎曲試驗之影響而完全恢復成原狀之情形時，上述內角成為180°。 （評價基準） 於在以內徑2 mm彎曲之狀態下固定，並於60±2℃、93±2%相對濕度（RH）之環境靜置24小時之較先前技術更嚴酷之條件進行靜態彎曲試驗，因此，試片之內角係以如下方式進行評價。若為A、B，則耐靜態彎曲性良好，當為A時，更優異。 A：110°以上 B：90°以上且未達110° C：未達90°＜Static bending test (

2 mm, standing for 24 hours)> Below, the method of static bending test will be described with reference to FIG. 1. The test piece 1 cut into a polyimide film of 15 mm×40 mm is bent at one and a half positions of the long side, and a metal piece with a thickness of 2 mm is sandwiched between the upper and lower sides of the long side of the test piece 1 2 (100 mm×30 mm×2 mm), and fix it with tape in such a way that the overlapping areas of both ends of the test piece 1 and the upper and lower surfaces of the metal piece 2 become 10 mm, respectively. Using a glass plate (100 mm×100 mm×0.7 mm) 3a, 3b, the metal piece 2 with the test piece 1 fixed therebetween is clamped from above and below, and the test piece 1 is fixed in a state where the inner diameter is bent by 2 mm. At this time, the dummy test pieces 4a, 4b are sandwiched between the metal piece 2 where the test piece 1 does not exist, and are fixed with tape so that the glass plates 3a, 3b become parallel. After the test piece fixed in such a bent state is allowed to stand for 24 hours in an environment of 60±2°C and 93±2% relative humidity (RH), the glass plate and the test piece fixing tape are peeled off to release the test piece. Exerted force. Thereafter, one end of the test piece was fixed, and the internal angle of the test piece was measured 30 minutes after the force applied to the test piece was released. In addition, when the film is completely restored to its original state without being affected by the static bending test, the internal angle becomes 180°. (Evaluation criteria) It is fixed in a state of bending with an inner diameter of 2 mm and is allowed to stand for 24 hours in an environment of 60±2°C and 93±2% relative humidity (RH). The static bending test is performed under more severe conditions than the prior art. Therefore, the inner angle of the test piece was evaluated as follows. If it is A or B, the static bending resistance is good, and when it is A, it is more excellent. A: 110° or more B: 90° or more and less than 110° C: less than 90°

＜Dynamic bending test (MIT method repeated bending test)＞ According to JIS 8115-2001, a MIT testing machine (manufactured by Toyo Seiki Co., Ltd., flexural fatigue testing machine MIT D-2) was used to cut a test piece of a polyimide film with a width of 15.0 mm × a length of 110 mm. 1 mm and a load of 500 g were repeatedly bent until the test piece broke, and the number of repeated bending was measured. The above repeated bending test was performed three times, and the average value of the repeated bending times of the three test results was obtained. (Evaluation criteria) If it is AΑ, Α, and B, the dynamic bending resistance is good, and when it is AΑ, Α, it is more excellent. AA: More than 50000 times A: More than 45,000 times and less than 50,000 times B: More than 35,000 times and less than 45,000 times C: less than 35,000 times

<YI value (yellowness) of polyimide film> The YI value is based on JIS K7373-2006, using an ultraviolet visible near-infrared spectrophotometer (Japan Spectroscopy Co., Ltd., V-7100), using a spectroscopic color measurement method, using an auxiliary illuminator C, a 2-degree field of view, above 250 nm And in the range below 800 nm, the penetration rate is measured at 1 nm intervals. Based on the measured penetration rate, the three stimulus values X, Y, and Z in the XYZ color system are obtained. According to the values of X, Y, and Z And calculated by the following formula. YI＝100（1.2769X－1.0592Z）/Y

<Film thickness measurement method> Using a digital linear gauge (manufactured by Ozaki Manufacturing Co., Ltd., model PDN12 Digital gauge), the film thickness of the four corners and the center of the test piece cut into 10 cm × 10 cm polyimide film is measured at a total of 5 points The average value of the measured values is the thickness of the polyimide film.

<Tensile modulus of elasticity of polyimide film> The test piece cut into a polyimide film of 15 mm×40 mm was adjusted for humidity for 2 hours under the conditions of a temperature of 25° C. and a relative humidity of 60%. According to JIS K7127, the stretching speed was set to 10 mm/min. The distance between the chucks was set at 20 mm, and the tensile modulus of elasticity at 25°C was measured. Use of tensile testing machine (Autograph AG-×1N manufactured by Shimadzu Corporation, load cell: SBL-1KN).

＜Pencil hardness＞ The pencil hardness is measured by adjusting the test sample at a temperature of 25°C and a relative humidity of 60% for 2 hours, using a test pencil specified in JIS-S-6006 and using Toyo Seiki Co., Ltd. The pencil scratch coating film hardness tester manufactured by Co., Ltd. performs the pencil hardness test (0.98 N load) specified in JIS K5600-5-4 (1999) on the film surface, and evaluates the highest pencil hardness that does not cause damage .

(Synthesis Example 1) In a 5 L separable flask, filled with dehydrated N,N-dimethylacetamide (DMAc) (2903 g) and 1,3-bis(3-aminopropyl) tetra A solution of methyl disiloxane (AprTMOS) (15.9 g), the liquid temperature is controlled to 30 °C, at this time, 4,4'-(hexafluoroisopropylidene) is slowly added in such a way that the temperature rises below 2 °C Base) diphthalic anhydride (6FDA) (14.6 g), using a mechanical stirrer for 30 minutes. To this, 2,2'-bis(trifluoromethyl)benzidine (TFMB) (387 g) was added, and after confirming complete dissolution, 4,4'-( Hexafluoroisopropylidene) diphthalic anhydride (6FDA) (548 g) was synthesized as a solution of polyimide precursor A in which polyimide precursor A was dissolved (solid content 25% by mass). The molar ratio of TFMB and AprTMOS (TFMB: AprTMOS) used in polyimide precursor A is 95:5.

(Synthesis Example 2) The polyimide precursor A solution was obtained in the same manner as in Synthesis Example 1 above. Under a nitrogen atmosphere, add the above polyimide precursor A solution (400 g), which was cooled to room temperature, to a 5 L separable flask. To this was added dehydrated N,N-dimethylacetamide (109 g) and stirred until it became homogeneous. Next, pyridine (41.4 g) and acetic anhydride (53.4 g) as catalysts were added and stirred at room temperature for 24 hours to synthesize a solution of polyimide A. To the obtained polyimide A solution, butyl acetate (406 g) was added and stirred until it became uniform, followed by slowly adding third butanol (3000 g) to obtain a white slurry. Filter the above slurry, wash the slurry in a beaker containing isopropyl alcohol (130 g), then filter, repeat this step 18 times, use a vacuum dryer to dry at 110°C to obtain polyacrylamide Imine A1 (polyimide material, polyimide powder). Furthermore, the third butanol (3000 g) was slowly added to obtain a white slurry, and after filtering the slurry of polyimide powder (0th time) and isopropyl alcohol 5 times , After 10 times, after 13 times, and after 15 times, the polyimide powder obtained each confirmed the amount of residual solvent. The results were 0 times: 16754 ppm, 5 times: 2500 ppm, 10 times: 220 ppm, after 13 times: 95 ppm, after 15 times: 50 ppm. The weight average molecular weight of polyimide A1 measured by GPC was 175,000. The average particle size of polyimide A1 is 250 μm. The amount of residual solvent in polyimide A1 was confirmed. As a result, the type of residual solvent was only DMAc. Regarding the amount of residual solvent, DMAc was 17 ppm.

(Comparative Synthesis Example 1) A polyimide A solution was obtained in the same manner as in Synthesis Example 2. The obtained polyimide A solution (346.4 g) was transferred to a 5 L separable flask, and n-butyl acetate (hereinafter referred to as butyl acetate) (235.3 g) was added and stirred until it became uniform. Next, slowly add methanol (523.5 g) to obtain a slightly turbid solution. Methanol (1.221 kg) was added to the turbid solution once to obtain a white slurry. The above slurry was filtered and washed 5 times with methanol to obtain polyimide CA1 (65.8 g). The average particle size of polyimide CA1 is 230 μm. The amount of residual solvent in polyimide CA1 was confirmed. As a result, the type of residual solvent was only DMAc, and the amount of residual solvent was 2500 ppm.

(Synthesis Examples 3 to 4, Comparative Synthesis Examples 2 to 3) A polyimide A solution was obtained in the same manner as in Synthesis Example 2. To the obtained polyimide A solution, butyl acetate (406 g) was added and stirred until it became uniform, and then, third butanol (3000 g) was slowly added to obtain a white slurry. The above slurry was filtered, the slurry was washed in a beaker with IPA (130 g), and then filtered, and this step was repeated only as many times as shown in Table 3, except that the use was the same as in Synthesis Example 1. Polyimide A2 and A3, and polyimide CA2 and CA3 were obtained by this method. The average particle size of polyimide A2 is 240 μm, and the amount of residual solvent, DMAc is 50 ppm. The average particle size of polyimide A3 was 230 μm, and the amount of residual solvent, DMAc was 95 ppm. The average particle size of polyimide CA2 is 250 μm, and the amount of residual solvent, DMAc is 220 ppm. The average particle size of polyimide CA3 is 240 μm, and the amount of residual solvent, DMAc is 2500 ppm.

(Examples 1 to 4, Comparative Examples 1 to 2) Using the polyimide A1 of Synthesis Example 2, the following procedures (C1) to (C3) were carried out to thereby produce polyimide films of the thicknesses described in Table 1 respectively. (C1) Dichloromethane was added to the polyimide A1 so that the solid content concentration of the polyimide A1 became 17% by mass to prepare a polyimide A1 dichloromethane solution with a solid content of 17% by mass. The viscosity of the polyimide A1 dichloromethane solution (solid content 17% by mass) at 25°C was 4600 cps. (C2) A sheet-shaped support (thickness 100 μm, SUS304, manufactured by Nisshin Steel Co., Ltd., SUS304 CSP-H-TA) with the film thickness after drying in the following circulating oven becomes the film shown in Table 1 Polyimide A1 dichloromethane solution (solid content concentration 17% by mass) was applied in a thick manner, and after natural drying, the polyimide resin coating film was peeled off. (C3) Cut the peeled polyimide resin coating into 150 mm×200 mm. Use two metal frames (outer size 150 mm×200 mm, inner size 130 mm×180 mm) to clamp the cut polyimide resin coating film, and use a fixing jig to coat the metal frame and polyimide resin coating The membrane is fixed. The fixed polyimide resin coating film was dried in a circulating oven at the heating temperature (°C) and time (minutes) shown in Table 1, to produce a polyimide film. Table 1 shows the evaluation results of the obtained polyimide film.

(Examples 5 to 6, Comparative Examples 3 to 5) Using the polyimide precursor A solution of Synthesis Example 1, the following procedures (H1) to (H2) were carried out, thereby producing polyimide films of the thicknesses described in Table 1, respectively. (H1) The polyimide precursor A solution (solid content concentration 25% by mass) of Synthesis Example 1 was applied to the film thickness shown in Table 1 after heating under the following nitrogen gas flow to the film thickness shown in Table 1. A sheet-shaped support (thickness 100 μm, SUS304, manufactured by Nisshin Steel Co., Ltd., SUS304 CSP-H-TA), the support and the coated polyimide precursor A solution in a circulating oven at 40 It was dried at 60°C for 60 minutes, and then dried at 120°C for 15 minutes to form a polyimide precursor resin coating film, after which the polyimide precursor resin coating film was peeled off. (H2) Cut the peeled polyimide precursor resin coating film to a size of 150 mm×200 mm. Use two metal frames (outer size 150 mm×200 mm, inner size 130 mm×180 mm) to clamp the cut polyimide precursor resin coating film, and fix the metal frame and polyimide with a fixture Precursor resin coating is fixed. The fixed polyimide precursor resin coating film was heated in an oven under a nitrogen gas flow (oxygen concentration of 100 ppm or less) at a heating rate of 10°C/min to the heating temperature (°C) shown in Table 1, at this temperature The time (minutes) shown in Table 1 below was heated to form a polyimide film.

*1：沸點未達100℃ *2：沸點為100℃以上 二氯甲烷：沸點40℃ DMAc（二甲基乙醯胺）：沸點165.5℃[Table 1]

*1: The boiling point is less than 100°C *2: The boiling point is more than 100°C Dichloromethane: boiling point 40°C DMAc (dimethylacetamide): boiling point 165.5°C

(Comparative example 6) Polyimide CA1 of Comparative Synthesis Example 1 was dissolved in a mixed solvent (8:2, volume ratio) of butyl acetate and PGMEA to prepare a polyimide CA1 solution with a solid content of 25% by mass. The viscosity of the polyimide CA1 solution (solid content 25% by weight) at 25°C is 40000 cps. Using the polyimide CA1 solution obtained in the above manner, the following procedures (iv) to (vi) were performed, thereby producing a polyimide film with a thickness of 50 μm. (Iv) The polyimide CA1 solution was coated on the glass and dried in a circulating oven at 120°C for 10 minutes. (V) Under a nitrogen gas flow (oxygen concentration of 100 ppm or less), the temperature is raised to 250°C at a temperature increase rate of 10°C/min, held at 250°C for 1 hour, and then cooled to room temperature. (Vi) Peel off from the glass to obtain a polyimide film.

(Comparative example 7) Using the polyimide precursor A solution of Synthesis Example 1, the following procedures (i) to (iii) were carried out, thereby producing polyimide films of the thickness described in Table 2 respectively. (I) The polyimide precursor A solution was coated on the glass and dried in a circulating oven at 120°C for 10 minutes. (Ii) Under a nitrogen gas flow (oxygen concentration of 100 ppm or less), the temperature is raised to 300°C at a temperature increase rate of 10°C/min, and after being held at 300°C for 60 minutes, it is cooled to room temperature. (Iii) Peel off from the glass to obtain each polyimide film.

*2：沸點為100℃以上 DMAc（二甲基乙醯胺）：沸點165.5℃ 乙酸丁酯：沸點126℃ PGMEA（丙二醇單甲醚乙酸酯）：沸點145℃[Table 2]

*2: Boiling point is above 100℃ DMAc (dimethylacetamide): Boiling point 165.5℃ Butyl acetate: Boiling point 126℃ PGMEA (Propylene glycol monomethyl ether acetate): Boiling point 145℃

(Examples 7 to 8, Comparative Examples 8 to 9) In Example 1, the polyimides A2 and A3 of Synthesis Examples 3 to 4 and the polyimides CA2 and CA3 of Comparative Synthesis Examples 2 to 3 were used instead of the polyimide A1 of Synthesis Example 2, except Otherwise, the polyimide films of the thickness described in Table 3 were obtained in the same manner as in Example 1, respectively. Table 3 shows the evaluation results of the obtained polyimide film.

[table 3]

(Examples 9 to 11) Using the polyimide A1 of Synthesis Example 2, the following procedures (C1') to (C3') were carried out, thereby producing polyimide films of the thicknesses described in Table 4 respectively. (C1') Add ethyl acetate (boiling point 77°C) to polyimide A1 so that the solid content concentration of polyimide A1 becomes 17% by mass to produce polyimide with solid content of 17% by mass A1 ethyl acetate solution. The viscosity of the polyethylenimine A1 ethyl acetate solution (solid content 17% by mass) at 25°C was 4800 cps. (C2') The sheet thickness of the support (thickness 100 μm, SUS304, manufactured by Nisshin Steel Co., Ltd., SUS304 CSP-H-TA) is shown in Table 4 after drying in the following circulating oven Polyimide A1 ethyl acetate solution (solid content 17% by mass) was applied as a film thickness, and after natural drying, the polyimide resin coating film was peeled off. (C3') Cut the peeled polyimide resin coating film to a size of 150 mm × 200 mm. Use two metal frames (outer size 150 mm×200 mm, inner size 130 mm×180 mm) to clamp the cut polyimide resin coating film, and use a fixing jig to coat the metal frame and polyimide resin coating The membrane is fixed. The fixed polyimide resin coating film was dried in a circulating oven at the heating temperature (°C) and time (minutes) shown in Table 4 to produce a polyimide film. Table 4 shows the evaluation results of the obtained polyimide film.

(Examples 12 to 14, Comparative Example 10) Using the polyimide A1 of Synthesis Example 2, the following procedures (C1'') to (C3'') were carried out to produce polyimide films of the thickness described in Table 4 respectively. (C1'') Add butyl acetate (boiling point 126°C) to polyimide A1 so that the solid content concentration of polyimide A1 becomes 17% by mass to produce a polyimide with solid content of 17% by mass Amine A1 butyl acetate solution. The viscosity of the polyimide A1 butyl acetate solution (solid content 17% by mass) at 25°C was 5000 cps. (C2'') on a sheet-shaped support (thickness 100 μm, SUS304, manufactured by Nisshin Steel Co., Ltd., SUS304 CSP-H-TA) with the film thickness after drying in the following circulating oven as shown in Table 4 Polyimide A1 butyl acetate solution (solid content 17% by mass) was applied in a film thickness manner, and after natural drying, the polyimide resin coating film was peeled off. (C3'') Cut the peeled polyimide resin coating into 150 mm×200 mm. Use two metal frames (outer size 150 mm×200 mm, inner size 130 mm×180 mm) to clamp the cut polyimide resin coating film, and use a fixing jig to coat the metal frame and polyimide resin coating The membrane is fixed. The fixed polyimide resin coating film was dried in a circulating oven at the heating temperature (°C) and time (minutes) shown in Table 4 to produce a polyimide film. Table 4 shows the evaluation results of the obtained polyimide film.

*1：沸點未達100℃ *2：沸點為100℃以上 乙酸乙酯：沸點77℃ 乙酸丁酯：沸點126℃ DMAc（二甲基乙醯胺）：沸點165.5℃[Table 4]

*1: Boiling point less than 100℃ *2: Boiling point above 100℃ Ethyl acetate: Boiling point 77℃ Butyl acetate: Boiling point 126℃ DMAc (Dimethylacetamide): Boiling point 165.5℃

(Synthesis Examples 5 to 10) The molar ratio of TFMB and AprTMOS (TFMB: AprTMOS) used in the synthesis of the polyimide precursor A of Synthesis Example 1 was changed from 95:5 to that shown in Table 5, except that the use was the same as Synthesis Example 1. In this way, solutions of polyimide precursors A4~A9 were obtained. In the synthesis of the polyimide in Synthesis Example 2, the solutions of the polyimide precursors A4 to A9 were used instead of the solution of the polyimide precursor A, respectively, except that the polyimide precursor A solution was obtained in the same manner as in Synthesis Example 2. Amidimide A4~A9 (polyimide material, polyimide powder). Table 5 shows the weight average molecular weight and the amount of residual solvent (DMAc) measured by GPC for each of the polyimides A4 to A9.

[table 5]

(Examples 15 to 20) In Example 1, instead of using polyimide A1, the polyimides A4 to A9 obtained in Synthesis Examples 5 to 10 were used, respectively, except that the same procedures as in Example 1 were performed to prepare tables respectively. 6. Polyimide film of the thickness described in 6. Table 6 shows the evaluation results of the obtained polyimide film.

[Table 6]

(Synthesis Examples 11-17) In the synthesis of the polyimide precursor A of Synthesis Example 1, instead of TFMB used as a diamine not containing Si, use diamine 1 shown in Table 7 in molar amounts equivalent to TFMB, and divide in this way Except for the modification, polyimide precursors A10 to A16 solutions were obtained in the same manner as in Synthesis Example 1, respectively. In the synthesis of the polyimide in Synthesis Example 2, polyimide precursor A10~A16 solutions were used instead of the polyimide precursor A solution, respectively, except that the polyimide precursor A solution was obtained in the same manner as in Synthesis Example 2. Amidimide A10~A16 (polyimide material, polyimide powder). Table 7 shows the weight average molecular weight and the amount of residual solvent (DMAc) measured by GPC for each polyimide A10 to A16.

[Table 7]

(Examples 21 to 27) In Example 1, instead of using polyimide A1, the polyimides A10 to A16 obtained in Synthesis Examples 11 to 17 were used, respectively, except that the same procedure as in Example 1 was performed to prepare tables respectively. Polyimide film of the thickness described in 8. Table 8 shows the evaluation results of the obtained polyimide film.

[Table 8]

(Synthesis Example 18) In the synthesis of the polyimide precursor A in Synthesis Example 1, instead of one half of 6FDA used as the acid dianhydride, a molar amount of pyromellitic dianhydride equivalent to 6FDA was used, except for changes in this way. A polyimide precursor A17 solution (solid content 25% by mass) was synthesized in the same manner as in Synthesis Example 1. The molar ratio of TFMB and AprTMOS (TFMB: AprTMOS) used in polyimide precursor A17 was 95:5. In the synthesis of polyimide in Synthesis Example 2, the solution of polyimide precursor A17 was used instead of the solution of polyimide precursor A, except that polyimide was obtained in the same manner as in Synthesis Example 2 A17 (polyimide material, polyimide powder). The weight average molecular weight of polyimide A17 measured by GPC was 176,000. The amount of residual solvent in polyimide A17 was confirmed. As a result, the type of residual solvent was only DMAc. Regarding the amount of residual solvent, DMAc was 22 ppm.

(Synthesis Example 19) In the synthesis of Polyimide Precursor A of Synthesis Example 1, instead of 6FDA used as acid dianhydride, a molar amount of 4,4'-oxydiphthalic anhydride equal to 6FDA was used in this way Except for the modification, a polyimide precursor A18 solution was obtained in the same manner as in Synthesis Example 1. The molar ratio of TFMB and AprTMOS (TFMB: AprTMOS) used in polyimide precursor A18 is 95:5. In the synthesis of polyimide in Synthesis Example 2, a solution of polyimide precursor A18 was used instead of the solution of polyimide precursor A, except that polyimide was obtained in the same manner as in Synthesis Example 2 A18 (polyimide material, polyimide powder). The weight average molecular weight of polyimide A18 measured by GPC was 178,000. The amount of residual solvent in polyimide A18 was confirmed. As a result, the type of residual solvent was only DMAc. Regarding the amount of residual solvent, DMAc was 20 ppm.

(Examples 28 to 29) In Example 1, instead of using polyimide A1, the polyimides A17 to A18 obtained in Synthesis Examples 18 to 19 were used, respectively, and the same procedures as in Example 1 were performed to prepare tables respectively. Polyimide film of the thickness described in 8. Table 9 shows the evaluation results of the obtained polyimide film.

[Table 9]

(Examples 30 to 58: Manufacturing of laminates) To a 40% by mass methyl isobutyl ketone solution of neopentaerythritol triacrylate was added 10 parts by mass relative to 100 parts by mass of neopentaerythritol triacrylate. 1-Hydroxycyclohexyl phenyl ketone (manufactured by BASF, Irgacure 184) to prepare a resin composition for hard coating. The resin composition for the hard coat layer was coated on each of the polyimide films of Examples 1 to 29, and was cured by irradiating ultraviolet rays at an exposure of 200 mJ/cm ² under a nitrogen gas flow to form a film thickness of 10 μm The cured film to produce a laminate. Since the polyimide film contains silicon atoms, the adhesion to the hard coat layer is also good.

1‧‧‧Sample 2‧‧‧Metal sheet 3a, 3b‧‧‧glass plate 4‧‧‧First transparent electrode 4a, 4b 5‧‧‧Second transparent electrode 6‧‧‧Next layer 7‧‧‧First lead 8‧‧‧Second pinout 10, 10', 10''‧‧‧Layered body 20, 20'‧‧‧ touch panel components 21‧‧‧End 22‧‧‧effective area 23‧‧‧Invalid area 24‧‧‧Connect 30‧‧‧ LCD display 40‧‧‧Organic electroluminescence display 41‧‧‧First Conducting Department 51‧‧‧Second Conducting Department 71‧‧‧First terminal 81‧‧‧Second terminal 100、200‧‧‧Liquid crystal display device 201‧‧‧The first conductive member 202‧‧‧Second conductive member 300, 400 ‧‧‧ organic electroluminescence display device

Figure 1 is a diagram for explaining the method of static bending test. 2 is a schematic plan view of one surface of an example of a touch panel member of the present invention. 3 is a schematic plan view of the other surface of the touch panel member shown in FIG. 2. FIG. 4 is an AA′ cross-sectional view of the touch panel component shown in FIGS. 2 and 3. 5 is a schematic plan view showing an example of a conductive member provided with the laminate of the present invention. 6 is a schematic plan view showing another example of the conductive member provided with the laminate of the present invention. 7 is a schematic cross-sectional view showing another example of the touch panel member of the present invention. 8 is a schematic cross-sectional view showing an example of a liquid crystal display device of the present invention. 9 is a schematic cross-sectional view showing another example of the liquid crystal display device of the present invention. 10 is a schematic cross-sectional view showing an example of the organic electroluminescence display device of the present invention. 11 is a schematic cross-sectional view showing another example of the organic electroluminescence display device of the present invention.

4‧‧‧First transparent electrode

7‧‧‧First lead

10‧‧‧Layered body

20‧‧‧Touch panel components

21‧‧‧End

22‧‧‧effective area

23‧‧‧Invalid area

24‧‧‧Connect

41‧‧‧First Conducting Department

71‧‧‧First terminal

Claims (13)

A polyimide film containing polyimide having a structure represented by the following general formula (1), as a residual solvent in the film, the content of an organic solvent having a boiling point of 1 atm and a boiling point of less than 100°C is 2000 ppm Below, and the content of the organic solvent with a boiling point of 1 atm or more above 100°C is 100 ppm or less, the total light transmittance measured according to JIS K7361-1 is 85% or more; General formula (1)

(In general formula (1), R ¹ represents a tetravalent group as a tetracarboxylic acid residue having an aromatic ring or an aliphatic ring, R ² represents a divalent group as a diamine residue, and 2.5 of the total amount of R ² Molar% or more and 50 mol% or less are diamine residues having a silicon atom in the main chain, 50 mol% or more and 97.5 mol% or less are the two having no silicon atom and having an aromatic ring or an aliphatic ring Amine residues; n represents the number of repeating units). The polyimide film as described in claim 1, wherein the 15 mm × 40 mm test piece is measured in accordance with JIS K7127 with the stretching speed set to 10 mm/min and the distance between the chucks set to 20 mm The tensile elastic modulus at 25°C is 1.8 GPa or more. The polyimide film according to claim 1 or 2, wherein the value obtained by dividing the yellowness calculated according to JIS K7373-2006 by the film thickness (μm) is 0.10 or less. The polyimide film according to claim 1 or 2, wherein R ¹ in the general formula (1) is selected from the group consisting of a residue of cyclohexanetetracarboxylic dianhydride and a residue of cyclopentanetetracarboxylic dianhydride Group, dicyclohexane-3,4,3',4'-tetracarboxylic dianhydride residue, cyclobutane tetracarboxylic dianhydride residue, pyromellitic dianhydride residue, 3,3', 4,4'-biphenyltetracarboxylic dianhydride residue, 2,2',3,3'-biphenyltetracarboxylic dianhydride residue, 4,4'-(hexafluoroisopropylidene) di-ortho Phthalic anhydride residues, 3,4'-(hexafluoroisopropylidene) diphthalic anhydride residues, 3,3'-(hexafluoroisopropylidene) diphthalic anhydride residues , 4,4'-oxydiphthalic anhydride residues, and 3,4'-oxydiphthalic anhydride residues of at least one group of tetravalent groups. The polyimide film according to claim 1 or 2, wherein the diamine residue of R ² in the general formula (1) having no silicon atom and having an aromatic ring or an aliphatic ring is selected Free transcyclohexanediamine residue, trans-1,4-bismethylenecyclohexanediamine residue, 4,4'-diaminodiphenylbenzene residue, 3,4'-diamine Diphenylsulfonyl residue, 2,2-bis(4-aminophenyl)propane residue, 3,3'-bis(trifluoromethyl)-4,4'-[(1,1,1 ,3,3,3-Hexafluoropropane-2,2-diyl)bis(4,1-phenoxy)]diphenylamine residue, 2,2-bis[3-(3-aminophenoxy Group) phenyl]-1,1,1,3,3,3-hexafluoropropane residue, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1 , 3,3,3-hexafluoropropane residue, and at least one divalent group in the group consisting of divalent groups represented by the following general formula (2); general formula (2)

(In the general formula (2), R ³ and R ⁴ each independently represent a hydrogen atom, an alkyl group, or a perfluoroalkyl group). The polyimide film according to claim 1 or 2, wherein in the above general formula (1), R ² represents a diamine residue selected from a group having no silicon atom, and has 1 or 2 in the main chain At least one divalent group of diamine residues of 1 silicon atom, 2.5 mole% or more and 50 mole% or less of the total amount of R ² is a diamine residue having 1 or 2 silicon atoms in the main chain, 50 mol% or more and 97.5 mol% or less are diamine residues having no silicon atom and having an aromatic ring or an aliphatic ring. A polyimide material, which is a polyimide material for manufacturing a polyimide film according to any one of claims 1 to 6, and With the structure represented by the above general formula (1), as the residual solvent, the content of the organic solvent having a boiling point of not more than 100°C at 1 atmosphere is 2000 ppm or less, and the content of the organic solvent having a boiling point of 100°C or more at 1 atmosphere is 100 Below ppm. A laminate having a polyimide film according to any one of claims 1 to 6 and a hard coat layer containing at least one polymer of a radically polymerizable compound and a cationic polymerizable compound. A member for a display, which is a polyimide film according to any one of claims 1 to 6, or has at least one type of polymerization containing the polyimide film and a radically polymerizable compound and a cationic polymerizable compound A hard-coated laminate of objects. The display member according to claim 9, which is for a flexible display. A touch panel member comprising: the polyimide film according to any one of claims 1 to 6, or a laminate, the laminate having the polyimide film and containing a radically polymerizable compound and a cation Hard coating of at least one polymer of polymerizable compound; A transparent electrode, which is arranged on one side of the polyimide film or the laminate, and is composed of a plurality of conductive parts; and A plurality of lead wires are electrically connected to at least one side of the end of the conductive portion. A liquid crystal display device comprising: the polyimide film according to any one of claims 1 to 6, or a laminate, the laminate having the polyimide film and containing a radically polymerizable compound and cationic polymerization A hard coating of at least one polymer of a sexual compound; and A liquid crystal display unit disposed on one surface side of the polyimide film or the laminate, and having a liquid crystal layer between opposing substrates. An organic electroluminescence display device comprising: the polyimide film according to any one of claims 1 to 6, or a layered body having the polyimide film and containing a radically polymerizable compound And a hard coat layer of at least one polymer of a cationic polymerizable compound; and An organic electroluminescence display portion, which is disposed on one side of the polyimide film or the laminate, and has an organic electroluminescence layer between opposing substrates.

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