TW201940570A - Hybrid resin composition - Google Patents

Abstract

The purpose of the present invention is to provide a resin composition for providing a plastic thin film that maintains excellent properties such as excellent heat resistance, low retardation, excellent flexibility, and excellent transparency, and that has excellent properties as a base film of a flexible device substrate such as a flexible display substrate that can be easily de-bonded from a support base material or a de-bonding layer formed on the support base material. This organic/inorganic hybrid resin composition is characterized by containing component (A), component (B), and component (C). Component (A): inorganic fine particles having an average particle size of 1-100 nm and having a surface modified with an alkoxy silane compound having two aromatic groups having 6-18 carbon atoms or one aromatic group having 7-18 carbon atoms. Component (B): a polyimide having fluorine. Component (C): an organic solvent.

Description

Mixed resin composition

The present invention relates to a mixed resin composition, and more particularly, the present invention particularly relates to a film capable of forming a peelable layer from a release layer formed on a carrier substrate by a mechanical peeling method, and is suitable for forming a flexible display. The composition of the flexible device substrate.

In recent years, with the rapid advancement of the electronics industry such as liquid crystal displays and organic electroluminescence displays, device thickness reduction, weight reduction, and flexibility have been demanded.
These devices form various electronic components on a glass substrate, such as thin-film transistors or transparent electrodes. However, by replacing this glass material with a soft and lightweight resin material, it is expected that the device itself will be thinner or lighter. Quantitative and flexible.
As candidates for such resin materials, polyimide has attracted attention, and various reports have been made on polyimide films.

For example, Patent Document 1 reports the invention of polyimide and its precursors that can be used as a plastic substrate for a flexible display. Tetracarboxylic acids containing alicyclic structures such as cyclohexylphenyltetracarboxylic acid and Polydiimide reacted with various diamines is one having excellent transparency and heat resistance.

In addition, in Patent Document 2, by adding silica sol to polyimide, the disadvantages of conventional plastic substrates are improved, that is, it has both linear expansion coefficient, transparency, and low birefringence, and can be fully expected to be applied to flexibility. Plastic substrate for display.

When pursuing the advantages of a plastic substrate, the operability or dimensional stability of the plastic substrate itself becomes a problem. That is, when the plastic substrate is formed into a thin film, it is easy to generate wrinkles or cracks, and it is difficult to guarantee its supportability. In addition, the position accuracy or the formation of a functional layer when a functional laminated layer such as a thin film transistor (TFT) or an electrode is formed It becomes difficult to maintain subsequent dimensional accuracy. Therefore, Non-Patent Document 1 proposes a method for forcibly separating a plastic substrate provided with an organic energy layer from glass after a predetermined functional layer is formed on a plastic substrate coated on glass and adhered to the glass. This is a so-called laser stripping step (EPLaR method (Electronics on Plastic by Laser Release) method).
[Prior technical literature]
[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2008-231327
[Patent Document 2] International Publication No. 2015/152178
[Non-patent literature]

[Non-Patent Document 1] E.I. Haskal et. Al. "Flexible OLED Displays Made with the EPLaR Process", Proc. Eurodisplay '07, pp. 36-39 (2007)

[Problems to be Solved by the Invention]

The technology described in the above-mentioned Non-Patent Document 1 uses glass as a supporting substrate, and a functional layer is formed on a plastic substrate fixed to the glass to ensure the operability or dimensional stability of the resin substrate. However, this EPLaR method (laser peeling method) is a method of damaging the interface between the resin substrate and the support substrate by laser irradiation when the resin substrate is separated from the self-supporting substrate. The problem of damage to the functional layer (TFT, etc.), the large damage to the resin substrate itself, and the problem of reduced transmittance may cause deterioration of the characteristics of the resin substrate and the functional layer formed thereon.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a composition that does not rely on the above-mentioned laser peeling technology and provides a base film for a flexible device substrate such as a flexible display substrate ( Base film) is a plastic film with excellent properties, especially excellent performance in maintaining heat resistance, low delay, excellent flexibility, and excellent transparency, and it can ensure its operability or dimensional stability, while providing A resin composition for a flexible device substrate that is mechanically peeled, peeled from a supporting substrate or a release layer, and a flexible device substrate obtained therefrom.

[Means to solve the problem]

As a result of careful review by the present inventors in order to achieve the above-mentioned object, it was found that a resin composition containing a silica sol modified with a specific siloxane is blended in a heat-resistant polymer used for both heat resistance and optical characteristics. The present invention is completed by maintaining excellent heat resistance, low retardation, excellent flexibility, and excellent transparency, and it can form a film that can be easily peeled off from a supporting substrate.

That is, the first aspect of the present invention relates to an organic-inorganic hybrid resin composition, which is an organic-inorganic hybrid resin composition including the following (A) component, (B) component, and (C) component,
(A) Component: The average particle diameter of the surface of the modified microparticles is modified by an alkoxysilane compound having two aromatic groups having 6 to 18 carbon atoms or 1 aromatic group having 7 to 18 carbon atoms. 100nm inorganic fine particles,
(B) component: polyfluorene imine having fluorine,
(C) component: organic solvent.
Second aspect: The organic-inorganic mixed resin composition according to the first aspect, wherein the alkoxysilane compound in the component (A) is a compound represented by the following formula (S1),

(Wherein R ¹ and R ² are each independently an alkyl group having 1 to 3 carbon atoms,
W is an integer from 1 to 3,
Y is an integer from 0 to 2, and W + Y = 3,
Z ¹ represents a group selected from the group consisting of a halogen atom, an alkyl group having 1 to 10 carbon atoms, and an alkoxy group having 1 to 10 carbon atoms, m represents an integer of 0 to 5, but m is an integer of 2 or more , Z ¹ may be the same or different groups).
Third aspect: The organic-inorganic mixed resin composition according to the first aspect or the second aspect, wherein m is 0 in the aforementioned formula.
Fourth aspect: The organic-inorganic mixed resin composition according to any one of the first aspect to the third aspect, wherein the polyimide of the component (B) is a tetracarboxylic dianhydride component and contains the following formula (A1) Polyimide polyimide of the reaction product of the diamine component of the fluorine-containing aromatic diamine shown,

(In the formula, B ² represents a divalent group selected from the group consisting of formulas (Y-1) to (Y-34).)




(In the formula, * represents a bond key).
The fifth aspect: The organic-inorganic mixed resin composition according to the fourth aspect, wherein the tetracarboxylic dianhydride component includes an alicyclic tetracarboxylic dianhydride represented by the following formula (C1),

[In the formula, B ¹ represents a 4-valent group selected from the group consisting of formulas (X-1) to (X-12),

(In the formula, plural Rs independently represent a hydrogen atom or a methyl group, and * represents a bonding bond)].
Sixth aspect: The organic-inorganic mixed resin composition according to any one of the first aspect to the fifth aspect, wherein the inorganic fine particles of the component (A) are silica particles.
The seventh aspect: The organic-inorganic mixed resin composition according to any one of the first to sixth aspects, wherein the mass ratio of the component (A) to the component (B) (A): (B) is 5: 5 to 9: 1.
Eighth aspect: The organic-inorganic mixed resin composition according to any one of the first to seventh aspects, wherein the inorganic fine particles of the component (A) are inorganic fine particles having an average particle diameter of 1 nm to 60 nm.
Ninth aspect: The organic-inorganic mixed resin composition according to any one of the first aspect to the eighth aspect, wherein the component (C) is an ester-based solvent.
The tenth aspect: A resin film which is formed of the organic-inorganic mixed resin composition according to any one of the first aspect to the ninth aspect and has a luminous transmittance of more than 80% at 400 nm, which is transparent and has Haze below 2%.
The eleventh aspect: A substrate for a flexible device, which is made of a resin film according to the tenth aspect.
Viewpoint 12: A method for manufacturing a substrate for a flexible device, comprising the following steps:
a) a step of forming a release layer on the supporting substrate;
b) a step of forming a resin film made of the organic-inorganic mixed resin composition according to any one of the first aspect to the ninth aspect to a substrate for a flexible device on the release layer; and
c) A step of peeling the resin film from the release layer to obtain a substrate for a flexible device.

[Inventive effect]

According to one aspect of the present invention, the organic-inorganic mixed resin composition can form a resin film having a low linear expansion coefficient, excellent heat resistance, low retardation, and excellent flexibility. In addition, it can be formed without impairing these properties. Resin film with easy peeling of self-supporting substrate.
In addition, the resin film formed from the organic-inorganic mixed resin composition of the present invention exhibits high heat resistance, low linear expansion coefficient, high transparency (high light transmittance, low yellowness), and low retardation. In addition, it is also excellent in flexibility, so it can be suitably used as a base film of a flexible device, particularly a flexible display substrate.
The organic-inorganic mixed resin composition of the present invention and the resin film formed from the composition can fully meet the requirements for high flexibility, low coefficient of linear expansion, and high transparency (high light transmittance, low The development of substrates for flexible devices, particularly substrates for flexible displays, such as yellowness) and low delay.

The present invention will be described in detail below.
The organic-inorganic hybrid resin composition of the present invention contains (A) component: inorganic fine particles modified with a specific alkoxysilane, (B) component: the following specific polyimide, and (C) component: organic The solvent contains a cross-linking agent and other ingredients if necessary.

[(A) component: Inorganic fine particles modified with a specific alkoxysilane]
The component (A) is an inorganic fine particle in which the surface of the fine particle is modified by a specific alkoxysilane described later. The average particle diameter of the inorganic fine particles can be appropriately selected depending on the purpose and the like. Among them, the average particle diameter is from the viewpoint of obtaining a more transparent film, and is preferably 1 nm to 100 nm, for example, more preferably 1 nm to 60 nm, or 9 nm to 60 nm, and particularly preferably 9 nm to 45 nm.
In the present invention, the average particle diameter of the inorganic fine particles is an average particle diameter value calculated from a specific surface area value measured by a nitrogen adsorption method using the inorganic fine particles.

Inorganic microparticles, particularly in the present invention, silica dioxide (silicon dioxide) particles, such as colloidal silica having a value of the above-mentioned average particle diameter, can be suitably used. The colloidal silica can be a silica sol. As the silica sol, an aqueous silica sol produced by a conventional method using an aqueous sodium silicate solution as a raw material, and an organic silica melt obtained by replacing the water of the aqueous silica sol dispersion medium with an organic solvent can be used.
Alternatively, an alkoxysilane such as methyl silicate or ethyl silicate in an organic solvent such as an alcohol, or a catalyst (for example, an alkali catalyst such as ammonia, an organic amine compound, or sodium hydroxide) may be used. In the presence, a silica sol obtained by performing hydrolysis and condensation, or an organic silicon melt adhesive in which the silica sol is replaced by a solvent with another organic solvent.
Among these, the silicone melt which uses an organic solvent as a dispersing medium in the present invention is preferable.

Examples of the organic solvent in the above-mentioned silicone melt adhesive include lower alcohols such as methanol, ethanol, and isopropanol; and N, N-dimethylformamide, N, N-dimethylacetamide, and the like Styramides; cyclic amines such as N-methyl-2-pyrrolidone; ethers such as γ-butyrolactone; ethylene glycols such as ethyl fibrinolysin, ethylene glycol, and acetonitrile.
Substitution of water in the dispersion medium of the aqueous silica sol or replacement of other organic solvents for the purpose can be performed by ordinary methods such as a distillation method and an ultrafiltration method.
The viscosity of the above-mentioned silicone melt adhesive is about 0.6 mPa ･ s to 100 mPa ･ s at 20 ° C.

Examples of the commercial products of the above-mentioned organosilicon melt include, for example, the trade name MA-ST-S (methanol-dispersed silica sol, manufactured by Nissan Chemical Industries, Ltd. (now: manufactured by Nissan Chemical Industries, Ltd., the same below)), and the product name. MT-ST (methanol-dispersed silica sol, manufactured by Nissan Chemical Industries, Ltd.), trade name MA-ST-UP (methanol-dispersed silica sol, manufactured by Nissan Chemical Industries, Ltd.), trade name MA-ST-M (methanol-dispersed silica Silica sol, manufactured by Nissan Chemical Industry Co., Ltd., trade name MA-ST-L (methanol-dispersed silica sol, manufactured by Nissan Chemical Industry Co., Ltd.), trade name IPA-ST-S (isopropanol-dispersed silica sol, Nissan Chemical Industry Co., Ltd.), trade name IPA-ST (Isopropanol-dispersed silica sol, Nissan Chemical Industry Co., Ltd.), trade name IPA-ST-UP (Isopropanol-dispersed silica sol, Nissan Chemical Industry Co., Ltd. )), Trade name IPA-ST-L (isopropanol dispersed silica sol, manufactured by Nissan Chemical Industry Co., Ltd.), trade name IPA-ST-ZL (isopropanol dispersed silica sol, manufactured by Nissan Chemical Industry Co., Ltd.) ), Trade name NPC-ST-30 (n-propyl cellolysin-dispersed silica sol, manufactured by Nissan Chemical Industries, Ltd.), trade name PGM-ST (1-methoxy-2-propanol-dispersed silica sol, (Nissan Chemical Industry Co., Ltd.), trade name DMAC-ST (dimethylacetamide dispersed silica sol, manufactured by Nissan Chemical Industries, Ltd.), trade name XBA-ST (xylene xylene n-butanol mixed solvent dispersed silica sol, manufactured by Nissan Chemical Industries, Ltd.) , Trade name EAC-ST (ethyl acetate dispersed silica sol, manufactured by Nissan Chemical Industry Co., Ltd.), trade name PMA-ST (propylene glycol monomethyl ether acetate dispersed silica sol, manufactured by Nissan Chemical Industry Co., Ltd.), commodity Name MEK-ST (methyl ethyl ketone dispersed silica sol, manufactured by Nissan Chemical Industry Co., Ltd.), trade name MEK-ST-UP (methyl ethyl ketone dispersed silica sol, manufactured by Nissan Chemical Industry Co., Ltd.), commodity Name MEK-ST-L (methyl ethyl ketone dispersed silica sol, manufactured by Nissan Chemical Industry Co., Ltd.) and trade name MIBK-ST (methyl isobutyl ketone dispersed silica sol, manufactured by Nissan Chemical Industry Co., Ltd.), PL-1-IPA (isopropanol-dispersed silica sol, manufactured by Fuso Chemical Industry Co., Ltd.), PL-1-TOL (toluene-dispersed silica sol, manufactured by Fuso Chemical Industry Co., Ltd.), PL-2L-PGME (propylene glycol monodisperse Methyl ether disperse silica sol, Fuso Chemical Industry Co., Ltd.), PL-2L-MEK (methyl ethyl ketone disperse silica sol, Fuso Chemical Industry Co., Ltd.), PL-3-ME (methanol dispersed silica sol, Fuso Chemical Industry Co., Ltd.) Etc., but it is not limited to these.
In the present invention, silicon dioxide, such as the silicon dioxide listed in the above-mentioned products used as an organic silicon melt adhesive, may be used in combination of two or more kinds.

[Specific alkoxysilane]
In the present invention, the alkoxysilane compound (hereinafter referred to as a specific alkoxysilane) used for the modification of the inorganic fine particles is an alkoxysilane compound having two aromatic groups having 6 to 18 carbon atoms, or 1 An aromatic alkoxysilane compound having 7 to 18 carbon atoms.
Examples of the aromatic group having 6 to 18 carbon atoms include a phenyl group and an aromatic group having 7 to 18 carbon atoms described later. Examples of the aromatic group having 7 to 18 carbon atoms include a group having 2 to 3 benzene rings and a group having 2 to 4 benzene rings that undergo condensation. Among them, an alkoxysilane having a structure represented by the following formula (S1) as a biphenyl group having an aromatic group having 7 to 18 carbon atoms is preferred.

In the formula, R ¹ and R ² are each independently an alkyl group having 1 to 3 carbon atoms,
W is an integer from 1 to 3,
Y is an integer from 0 to 2, and W + Y = 3,
Z ¹ represents a group selected from the group consisting of a halogen atom, an alkyl group having 1 to 10 carbon atoms, and an alkoxy group having 1 to 10 carbon atoms, m represents an integer of 0 to 5, but m is an integer of 2 or more , Z ¹ may be the same or different.
Among them, it is preferable that m is 0 (biphenyl is not substituted) and an alkoxysilane.

Examples of the alkoxysilane compound represented by the formula (S1) include 4-biphenyltrimethoxysilane, 4-biphenyltriethoxysilane, 3-biphenyltrimethoxysilane, 3- Biphenyltriethoxysilane and so on.

When inorganic fine particles modified with a specific alkoxysilane are used, for example, when silicon dioxide particles are used as the inorganic fine particles, the specific alkoxysilane can be prepared by contacting the specific alkoxysilane with the silicon dioxide particles. When a specific alkoxysilane is brought into contact with silicon dioxide particles, for example, a silanol group or an alkoxysilyl group in a specific alkoxysilane is subjected to a condensation reaction with a hydroxyl group existing on the surface of the silicon dioxide particles to form a bond. Specific alkoxysilane modified silica particles on the surface.
Specifically, for example, by mixing a colloidal solution of silicon dioxide particles and a specific alkoxysilane solution prepared in advance, it is possible to prepare a silicon dioxide particle modified with a specific alkoxysilane. Mixing the colloidal solution with a specific alkoxysilane solution can be performed at normal temperature, or it can be performed while heating. From the viewpoint of reaction efficiency, it is preferable to perform the mixing while heating. When mixing while heating, the heating temperature can be appropriately selected according to the solvent and the like. When the heating temperature is, for example, 60 ° C or higher, the reflux temperature of the solvent is preferred.

The mixing ratio of the specific alkoxysilane and the silica particles can be appropriately selected depending on the purpose and the like. For example, the mass ratio of silica particles to a specific alkoxysilane (silicon dioxide particles / specific alkoxysilane) is preferably 70/30 to 99/1, and more preferably 70/30 to 90/10. It is more preferably 80/20 to 90/10. Here, the mass number of the silicon dioxide particles is calculated from the composition formula of the silicon dioxide particles in the form of SiO ₂ .

[(B) Ingredient: Polyimide]
In the present invention, the polyfluorene imine preferably used is a polyfluorine having a fluorine, and more specifically, a polyfluorene obtained by reacting a tetracarboxylic dianhydride component with a diamine component containing a fluorine-containing aromatic diamine. Polyfluorene imine (fluorenimide) obtained by sulfonating imine (reaction product).
Among them, the fluorine-containing aromatic diamine is preferably a diamine represented by the following formula (A1).

(In the formula, B ² represents a divalent group selected from the group consisting of formulae (Y-1) to (Y-34).)




(In the formula, * represents a bond.)

The use of an alicyclic tetracarboxylic dianhydride as the tetracarboxylic dianhydride component is preferable from the viewpoints of transparency and solubility in a solvent.
Among them, the alicyclic tetracarboxylic dianhydride is preferably a tetracarboxylic dianhydride represented by the following formula (C1).

[In the formula, B ¹ represents a tetravalent group selected from the group consisting of formulae (X-1) to (X-12).

(In the formula, plural Rs independently represent a hydrogen atom or a methyl group, and * represents a bonding bond.)]

Among the tetracarboxylic dianhydrides represented by the above formula (C1), it is preferable that B ¹ in the formula is a compound represented by the formula (X-1), (X-4), (X-6), (X-7) .
Among the diamines represented by the above (A1), B ² in the formula is preferably a compound represented by the formulae (Y-12) and (Y-13).
A preferred example is a polyimide system obtained by subjecting a tetracarboxylic dianhydride represented by the above formula (C1) to a polyamidoacid obtained by reacting a diamine represented by the above formula (A1) with a polyimide, comprising the following formula ( 2) A monomer unit represented.

In order to obtain a resin film (flexible device substrate) having low linear expansion coefficient, low retardation, and high transparency for the purpose of the present invention, compared to the total mole of the tetracarboxylic dianhydride component Alicyclic tetracarboxylic dianhydride, for example, the tetracarboxylic dianhydride represented by the above formula (C1) is preferably 90 mol% or more, more preferably 95 mol% or more, especially all (100 mol%) ) Is most preferably a tetracarboxylic dianhydride represented by the above formula (C1).
Similarly, in order to obtain a resin film (flexible device substrate) having the above-mentioned characteristics of low linear expansion coefficient, low retardation, and high transparency and excellent flexibility, the total mole number with respect to the diamine component, The fluorine-containing aromatic diamine, for example, the diamine represented by formula (A1) is preferably 90 mol% or more, more preferably 95 mol% or more. The entire diamine component (100 mol%) may be a diamine represented by the formula (A1).

As an example of a preferable aspect, the polyimide used in the present invention includes a monomer unit represented by the following formula (1).

The monomer unit represented by the above formula (1) is preferably represented by formula (1-1) or formula (1-2), and more preferably represented by formula (1-1).

According to a preferred aspect of the present invention, the polyimide system used in the present invention contains a monomer unit represented by the formula (2). The polyfluorene imide used in the present invention may include both a monomer unit represented by the formula (1) and a monomer unit represented by the formula (2).

The monomer unit represented by the formula (2) is preferably represented by the formula (2-1) or (2-2), and more preferably represented by the formula (2-1).

When the polyfluorene imide used in the present invention includes the monomer unit represented by the above formula (1) and the monomer unit represented by the formula (2), the molar ratio of the polyfluorene imine chain and the unit represented by the formula (1) Body unit: monomer unit represented by formula (2) = 10: 1 ~ 1: 10 is better to contain, more preferably 8: 2 ~ 2: 8 to contain, and 6: 4 ~ 4: 6 to contain The ratio is better.

The polyfluorene imide of the present invention is derived from a monomer derived from an alicyclic tetracarboxylic dianhydride component containing a tetracarboxylic dianhydride represented by the aforementioned formula (C1) and a diamine component containing a diamine represented by the formula (A1). The bulk unit may include other monomer units in addition to the monomer units represented by the formulas (1) and (2), for example. The content ratio of these other monomer units can be arbitrarily set without impairing the characteristics of the resin film formed from the organic-inorganic mixed resin composition of the present invention.
The ratio is relative to the monomer unit derived from the alicyclic tetracarboxylic dianhydride component containing the tetracarboxylic dianhydride represented by the aforementioned formula (C1) and the diamine component containing the diamine represented by the formula (A1), For example, the mole number of the monomer unit represented by formula (1) or the monomer unit represented by formula (2), or the total mole number of monomer units represented by formula (1) and monomer units represented by formula (2) It is preferably less than 20 mole%, more preferably less than 10 mole%, and even more preferably less than 5 mole%.

Examples of such other monomer units include, but are not limited to, those having other polyfluorene imine structures represented by formula (3).

In formula (3), A represents a tetravalent organic group, and preferably represents a tetravalent group represented by any one of the following formulae (A-1) to (A-4). In the formula (3), B represents a divalent organic group, and preferably represents a divalent group represented by any one of the formulae (B-1) to (B-11). In each formula, * represents a bond. When A is a tetravalent group represented by any of the following formulae (A-1) to (A-4) in formula (3), B may be the formulae (Y-1) to (Y- 34) A bivalent base represented by any one of them. Or in the formula (3), when B is a divalent group represented by any one of the following formulae (B-1) to (B-11), A may also be the aforementioned formulae (X-1) to (X-12) 4).

When the polyfluorene imide used in the present invention includes a monomer unit represented by the formula (3), A and B may include, for example, only one monomer unit composed of one of the groups exemplified by the following formula, A and B At least one of them may include two or more kinds of monomer units selected from two or more kinds of groups exemplified below.

In the polyfluorene imide used in the present invention, each monomer unit may be bonded in any order.

As a preferred example, polyimide having a monomer unit represented by the above formula (1) can be obtained by using a bicyclic [2,2,2] octane-2,3,5 as a tetracarboxylic dianhydride component, A 6-tetracarboxylic dianhydride and a diamine represented by the following formula (4) as a diamine component are polymerized in an organic solvent to obtain a polyfluorinated acid, which is obtained by fluorination.
When the polyfluorene imide used in the present invention has a monomer unit represented by the above formula (2), the polyfluorene imine can be used as a tetracarboxylic dianhydride component as a 1,2,3,4-ring Butane tetracarboxylic dianhydride and a diamine represented by the following formula (4) as a diamine component are obtained by polymerizing a polyamidic acid obtained by polymerization in an organic solvent and then performing imidization.
In addition, in addition to the monomer unit represented by the above formula (1), the polyfluorene imide used in the present invention includes the monomer units represented by the formula (2), and each unit represented by the formula (1) and the formula (2) is included. The polyfluorene imine in the unit can be obtained by using the above tetracarboxylic dianhydride as a tetracarboxylic dianhydride component, and by using 1,2,3,4-cyclobutane tetracarboxylic dianhydride and a diamine. The diamine represented by the following formula (4) as a component is obtained by polyimidation of a polyamic acid obtained by polymerization in an organic solvent.

Examples of the diamine represented by the formula (4) include 2,2'-bis (trifluoromethyl) benzidine, 3,3'-bis (trifluoromethyl) benzidine, and 2,3'-bis (tri (Fluoromethyl) benzidine.
Among them, as the diamine component, the resin film (the substrate for a flexible device) of the present invention has a lower coefficient of linear expansion, and the resin film (the substrate for a flexible device) is made more transparent. From the viewpoint, it is preferable to use 2,2'-bis (trifluoromethyl) benzidine represented by the following formula (4-1) or 3,3'-bis (tri) represented by the following formula (4-2) Fluoromethyl) benzidine, especially 2,2'-bis (trifluoromethyl) benzidine is preferred.

The polyfluorene imide used in the present invention is not only composed of an alicyclic tetracarboxylic dianhydride component containing a tetracarboxylic dianhydride represented by the aforementioned formula (C1) and a diamine component containing a diamine represented by the formula (A1). Derived monomer units include, for example, the monomer unit represented by the above formula (1) and the monomer unit represented by the formula (2), and when there are other monomer units represented by the formula (3), the formula (1), The polyfluorene imine of each monomer unit represented by the formula (2) and the formula (3) can be represented by the above-mentioned two kinds of tetracarboxylic dianhydride as a tetracarboxylic dianhydride component and the following formula (5) Tetracarboxylic dianhydride and a diamine represented by the above formula (4) as a diamine component and a diamine represented by the following formula (6) are polymerized in an organic solvent to perform amidimidation. And get.

A in the formula (5) and B in the formula (6) have the same meanings as A and B in the formula (3), respectively.

Specifically, the tetracarboxylic dianhydride represented by formula (5) includes pyromellitic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 3,3', 4, 4'-benzophenone tetracarboxylic dianhydride, 3,3 ', 4,4'-diphenyl ether tetracarboxylic dianhydride, 3,3', 4,4'-diphenylphosphonium tetracarboxylic dianhydride Anhydride, 4,4 '-(hexafluoroisopropylidene) bisphthalic dianhydride, 11,11-bis (trifluoromethyl) -1H-difluoro [3,4-b: 3', 4 '-i] xanthene-1,3,7,9- (11H-tetraketone), 6,6'-bis (trifluoromethyl)-[5,5'-diisobenzofuran] -1, 1 ', 3,3'-tetraone, 4,6,10,12-tetrafluorodifuran [3,4-b: 3', 4'-i] dibenzo [b, e] [1,4 ] Dioxin-1,3,7,9-tetraone, 4,8-bis (trifluoromethoxy) benzo [1,2-c: 4,5-c '] difuran-1,3,5 , 7-tetraketone, and N, N '-[2,2'-bis (trifluoromethyl) biphenyl-4,4'-diyl] bis (1,3-dioxo-1,3- Dihydroisobenzoan-5-carboxamide) and other aromatic tetracarboxylic acids; 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,3,4- Cyclohexanetetracarboxylic dianhydride, and alicyclic tetracarboxylic dianhydride of 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic dianhydride; and 1,2 , 3,4-butane tetra The aliphatic tetracarboxylic dianhydride such as carboxylic dianhydride is not limited thereto.
Among these, it is preferable that A in formula (5) is a tetravalent dianhydride represented by any of the aforementioned formulae (A-1) to (A-4), that is, 11,11- Bis (trifluoromethyl) -1H-difluoro [3,4-b: 3 ', 4'-i] xanthene-1,3,7,9- (11H-tetraone), 6,6'- Bis (trifluoromethyl)-[5,5'-diisobenzofuran] -1,1 ', 3,3'-tetraone, 4,6,10,12-tetrafluorodifuran [3,4 -b: 3 ', 4'-i] dibenzo [b, e] [1,4] dioxin-1,3,7,9-tetraone, and 4,8-bis (trifluoromethoxy) Benzo [1,2-c: 4,5-c '] difuran-1,3,5,7-tetraone is a preferred compound.

Examples of the diamine represented by the formula (6) include 2- (trifluoromethyl) benzene-1,4-diamine, 5- (trifluoromethyl) benzene-1,3-diamine, and 5- (Trifluoromethyl) benzene-1,2-diamine, 2,5-bis (trifluoromethyl) -benzene-1,4-diamine, 2,3-bis (trifluoromethyl) -benzene- 1,4-diamine, 2,6-bis (trifluoromethyl) -benzene-1,4-diamine, 3,5-bis (trifluoromethyl) -benzene-1,2-diamine, tetra (Trifluoromethyl) -1,4-phenylenediamine, 2- (trifluoromethyl) -1,3-phenylenediamine, 4- (trifluoromethyl) -1,3-phenylenediamine, 2 -Methoxy-1,4-phenylenediamine, 2,5-dimethoxy-1,4-phenylenediamine, 2-hydroxy-1,4-phenylenediamine, 2,5-dihydroxy-1 1,4-phenylenediamine, 2-fluorobenzene-1,4-diamine, 2,5-difluorobenzene-1,4-diamine, 2-chlorobenzene-1,4-diamine, 2,5- Dichlorobenzene-1,4-diamine, 2,3,5,6-tetrafluorobenzene-1,4-diamine, 4,4 '-(perfluoropropane-2,2-diyl) diphenylamine, 4,4'-oxybis [3- (trifluoromethyl) aniline], 1,4-bis (4-aminophenoxy) benzene, 1,3'-bis (4-aminophenoxy) Benzene, 1,4-bis (3-aminophenoxy) benzene, benzidine, 2-methylbenzidine, 3-methylbenzidine, 2- (trifluoromethyl) benzidine, 3- (tri (Fluoromethyl) benzidine, 2,2'-dimethylbenzidine (m-benzidine), 3,3'-dimethylbenzidine (o- Toluidine), 2,3'-dimethylbenzidine, 2,2'-dimethoxybenzidine, 3,3'-dimethoxybenzidine, 2,3'-dimethoxybenzidine , 2,2'-dihydroxybenzidine, 3,3'-dihydroxybenzidine, 2,3'-dihydroxybenzidine, 2,2'-difluorobenzidine, 3,3'-difluorobenzidine , 2,3'-difluorobenzidine, 2,2'-dichlorobenzidine, 3,3'-dichlorobenzidine, 2,3'-dichlorobenzidine, 4,4'-diaminobenzene Formamidine, 4-aminophenyl-4'-aminobenzoate, octafluorobenzidine, 2,2 ', 5,5'-tetramethylbenzidine, 3,3', 5,5 '-Tetramethylbenzidine, 2,2', 5,5'-tetrakis (trifluoromethyl) benzidine, 3,3 ', 5,5'-tetrakis (trifluoromethyl) benzidine, 2 ,, 2 ', 5,5'-tetrachlorobenzidine, 4,4'-bis (4-aminophenoxy) biphenyl, 4,4'-bis (3-aminophenoxy) biphenyl, 4 , 4 '-{[3,3 ”-bis (trifluoromethyl)-(1,1': 3 ', 1” -terphenyl) -4,4 ”-diyl] -bis (oxy)} Diphenylamine, 4,4 '-{[(perfluoropropane-2,2-diyl) bis (4,1-phenylene)] bis (oxy)} diphenylamine, and 1- (4-aminobenzene Aryl) -2,3-dihydro-1,3,3-trimethyl-1H-indene-5 (or 6) amine, etc .; aromatic diamines; 4,4'-methylenebis (cyclohexylamine) ), 4,4'-methylenebis (3-methyl ring Methylamine), isophorone diamine, trans-1,4-cyclohexanediamine, cis-1,4-cyclohexanediamine, 1,4-cyclohexanebis (methylamine), 2 , 5-bis (aminomethyl) bicyclo [2.2.1] heptane, 2,6-bis (aminomethyl) bicyclo [2.2.1] heptane, 3,8-bis (aminomethyl) Tricyclo [5.2.1.0] decane, 1,3-diamine fund adamantane, 2,2-bis (4-aminocyclohexyl) propane, 2,2-bis (4-aminocyclohexyl) hexafluoro Propane, 1,3-propanediamine, 1,4-tetramethylenediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,7-heptamethylene diamine, 1 Aliphatic diamines such as, 8-octanediamine, and 1,9-nonanediamine, but are not limited thereto.
Among these, it is preferable that B in formula (6) is a divalent aromatic diamine represented by any one of the foregoing formulae (B-1) to (B-11), that is, 2,2 '-Bis (trifluoromethoxy)-(1,1'-biphenyl) -4,4'-diamine [another name: 2,2'-dimethoxybenzidine], 4,4 '-(Perfluoropropane-2,2-diyl) diphenylamine, 2,5-bis (trifluoromethyl) benzene-1,4-diamine, 2- (trifluoromethyl) benzene-1,4 -Diamine, 2-fluorobenzene-1,4-diamine, 4,4'-oxybis [3- (trifluoromethyl) aniline], 2,2 ', 3,3', 5,5 ', 6,6'-octafluoro [1,1'-biphenyl] -4,4'-diamine [another name: octafluorobenzidine], 2,3,5,6-tetrafluorobenzene-1, 4-diamine, 4,4 '-{[3,3 ”-bis (trifluoromethyl)-(1,1': 3 ', 1” -terphenyl) -4,4 ”-diyl] -Bis (oxy)} diphenylamine, 4,4 '-{[(perfluoropropane-2,2-diyl) bis (4,1-phenylene)] bis (oxy)} diphenylamine, and 1- (4-Aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-indene-5 (or 6) amine is a preferred diamine.

＜ Synthesis of Polyamic Acid ＞
In a preferred embodiment, the polyfluorene imide used in the present invention, as described above, comprises a tetracarboxylic dianhydride component containing the alicyclic tetracarboxylic dianhydride represented by the above formula (C1) and a compound containing the above formula (A1) The polyfluorinated acid obtained by the reaction of the diamine component of the fluorine-containing aromatic diamine shown is obtained by fluoramidation.
Specifically, for example, a preferable example is that by using bicyclo [2.2.2] octane-2,3,5,6-tetracarboxylic dianhydride, sometimes 1,2,3,4-cyclobutane tetra A carboxylic dianhydride, preferably a tetracarboxylic dianhydride component formed from a tetracarboxylic dianhydride represented by the above formula (5), and a diamine represented by the above formula (4), and more preferably the above formula (6) The diamine component formed by the diamine component represented by) is obtained by polymerizing polyamidoacid obtained by polymerization in an organic solvent, and performing imidization.
From the viewpoint of the reaction of the two components to the polyamic acid, it is relatively easy to proceed in an organic solvent, and the viewpoint of not generating by-products is preferable.

The input ratio (mole ratio) of the diamine component in the reaction of these tetracarboxylic dianhydride components with the diamine component can be considered polyamic acid, and polyimide obtained by imidizing amidine. The molecular weight and the like are appropriately set, but the diamine component 1 may generally be a tetracarboxylic dianhydride component of about 0.8 to 1.2, for example, about 0.9 to 1.1, and preferably about 0.95 to 1.02. As with the normal polycondensation reaction, the closer this Mohr ratio is to 1.0, the larger the molecular weight of the polyamidic acid produced.

The organic solvent used in the reaction between the tetracarboxylic dianhydride component and the diamine component is not particularly limited as long as it does not affect the reaction and the produced polyamic acid will dissolve. Specific examples are given below.
Examples include m-cresol, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, N, N-dimethylformamidine, N, N-dimethylacetamide, 3-methoxy-N, N-dimethylpropylamidine, 3-ethoxy-N, N-dimethylpropylamidine, 3-propyl Oxy-N, N-dimethylpropylfluorene, 3-isopropoxy-N, N-dimethylpropylfluoramine, 3-butoxy-N, N-dimethylpropylfluorene Amine, 3-sec-butoxy-N, N-dimethylpropylamidamine, 3-tert-butoxy-N, N-dimethylpropylamidamine, γ-butyrolactone, N- Methylcaprolactam, dimethylmethylene fluorene, tetramethylurea, pyridine, dimethyl fluorene, hexamethylmethylene fluorene, isopropanol, methoxymethylpentanol, dipentene, ethylpentyl Methyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cellolysin, ethyl cellolysin, methyl cellosolve acetate, Ethylcellosolve acetate, butylcarbitol, ethylcarbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, Propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol-ter t-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, diethylene glycol Propylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, pentyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methyl Cyclohexene, dipropyl ether, dihexyl ether, dioxane, n-hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, vinyl carbonate, propylene carbonate, methyl lactate, Ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, 3-ethoxypropionic acid Isopropyl, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, 3-methoxypropionic acid propyl, 3-methoxypropionic acid butyl, Diethylene glycol dimethyl ether and 4-hydroxy-4-methyl-2-pentanone, etc., but And the like is not limited thereto. These can be used alone or in combination of two or more.
Moreover, even if it is a solvent which does not melt | dissolve a polyamic acid, in the range which the produced polyamic acid does not precipitate, it can mix and use with the said solvent. In addition, the water in the organic solvent hinders the polymerization reaction and further causes the generated polyamic acid to hydrolyze. Therefore, it is preferable to use an organic solvent to dehydrate and dry as much as possible.

The method for reacting the tetracarboxylic dianhydride component and the diamine component in an organic solvent includes a dispersion or solution in which the diamine component is dispersed or dissolved in an organic solvent, and the tetracarboxylic dianhydride component is directly added or added. A method for dispersing or dissolving a tetracarboxylic acid component in an organic solvent. Conversely, a method for adding a diamine component to a dispersion or solution in which a tetracarboxylic dianhydride component is dispersed or dissolved in an organic solvent. A method of alternately adding a dianhydride component and a diamine compound component, and the like may be any of these methods.
In addition, when the tetracarboxylic dianhydride component and / or the diamine component are made of a plurality of compounds, the reaction may be performed in a state of being mixed in advance, or may be individually reacted sequentially, and further, the low molecular weight body of the individual reaction may be performed. Mixed reaction as high molecular weight body.

The temperature at which the polyamic acid is synthesized can be appropriately set within the range from the melting point to the boiling point of the solvent used above. For example, any temperature of -20 ° C to 150 ° C can be selected, which can be -5 ° C to 150 ° C. The temperature is usually about 0 to 150 ° C, preferably about 0 to 140 ° C.
The reaction time depends on the reaction temperature or the reactivity of the raw materials, so it cannot be specified in general. Usually, it is about 1 to 100 hours.
In addition, the reaction can be carried out at any concentration. However, when the concentration is too low, it is difficult to obtain a polymer with a high molecular weight. When the concentration is too high, the viscosity of the reaction solution becomes too high and it is difficult to uniformly stir. The total concentration in the reaction solution of the amine component is preferably 1 to 50% by mass, and more preferably 5 to 40% by mass. The reaction proceeds at a high concentration in the initial stage, and then an organic solvent may be added.

＜ Imidation of Polyacrylic Acid ＞
Examples of the method for polyimidating polyimide include thermal imidization in which a solution of polyimide is directly heated, and catalyst imidization in which a catalyst is added to a solution of polyimide.
The temperature at which the polyamidic acid is thermally fluorinated in the solution is 100 ° C to 400 ° C, preferably 120 ° C to 250 ° C. It is better to remove the water generated by the fluorination reaction to the outside of the system. .

The chemical (catalyst) / imidization of polyamic acid is based on the addition of alkaline catalyst and acid anhydride to the solution of polyamic acid at a temperature of -20 ~ 250 ℃, preferably 0 ~ 180 ℃. This was performed by stirring the inside of the system.
The amount of the alkaline catalyst is 0.5 to 30 mole times of the amino acid group of the polyamino acid, preferably 1.5 to 20 mole times of the amino acid group of the polyamine, and the amount of the acid anhydride is 1 to 1 of the amino acid group of the polyamino acid. 50 mol times, preferably 2 to 30 mol times.

Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine, and 1-ethylpiperidine. Among them, pyridine and 1-ethylpiperidine have a reaction place. It needs moderate alkalinity, so it is better.
The rate of imidization through the catalyst imidization can be controlled by adjusting the amount of the catalyst, the reaction temperature, and the reaction time.

In the polyfluorene imide used in the present invention, the dehydration ring closure rate (fluorine imidization rate) of the amino acid group is not necessarily 100%, and can be arbitrarily adjusted and used according to the purpose or purpose. Particularly good is more than 50%.

In the present invention, without the step of polymer recovery described below, the above-mentioned amidine imidization reaction solution can be directly used to prepare an organic-inorganic mixed resin composition. At this time, after filtering the reaction solution, the filtrate itself or the Diluted or concentrated filtrate can be used for organic-inorganic mixed resin composition. When filtered in this way, impurities that cause deterioration of the heat resistance, softness, or linear expansion coefficient characteristics of the obtained organic-inorganic mixed resin film can be reduced.

In addition, the polyimide used in the present invention is formed from an organic-inorganic hybrid resin composition in consideration of the strength of a resin film (organic-inorganic hybrid resin film) obtained from an organic-inorganic hybrid resin composition and a supporting substrate. The workability of the resin film, the uniformity of the organic-inorganic mixed resin film, and the like, the weight average molecular weight (Mw) obtained by polystyrene conversion of gel permeation chromatography (GPC) is preferably 5,000 to 200,000.

＜ Polymer recycling ＞
When the polymer component is recovered from the reaction solution of polyamidic acid and polyimide, and this is used for the preparation of polyimide and for the preparation of the organic-inorganic mixed resin composition, the reaction solution is put into a weak solvent so that Precipitation is sufficient. Examples of the weak solvent used for the precipitation include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, isopropanol, and water. The polymer precipitated by being put into a weak solvent can be recovered by filtration, and then can be dried at room temperature or under normal pressure or reduced pressure.
In addition, when the polymer recovered by precipitation is redissolved in an organic solvent, and the operation of reprecipitation and recovery is repeated 2 to 10 times, impurities in the polymer can be reduced. As the weak solvent at this time, for example, when three or more types of weak solvents such as alcohols, ketones, and hydrocarbons are used, the efficiency of purification is further improved, so it is preferable.

In the reprecipitation recovery step, the organic solvent that dissolves the resin component is not particularly limited. Specific examples include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone, N -Ethylpyrrolidone, N-vinylpyrrolidone, dimethyl sulfene, tetramethylurea, pyridine, dimethyl fluorene, hexamethyl fluorene, γ-butyrolactone, 1,3-dimethyl-imidazole Porphyrinone, dipentene, ethylpentyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, cyclohexanone, vinyl carbonate, propylene carbonate , Diglyme, 4-hydroxy-4-methyl-2-pentanone, etc. These solvents can be used by mixing two or more kinds.

[Other inorganic fine particles]
The organic-inorganic hybrid resin composition of the present invention may include other inorganic fine particles than the above-mentioned inorganic fine particles, that is, other inorganic fine particles that have not been modified with a specific alkoxysilane compound. The content of the other inorganic fine particles not modified with the specific alkoxysilane compound at this time is 50 mass based on the total amount of the inorganic fine particles based on the component (A) of the present case and the other inorganic fine particles not modified with the specific alkoxysilane compound. % To 0% by mass, preferably 20% to 0% by mass.

[Crosslinking agent]
The organic-inorganic mixed resin composition of the present invention may further include a crosslinking agent. The cross-linking agent used herein may be a compound composed of only a hydrogen atom, a carbon atom, and an oxygen atom, or a compound composed of only a hydrogen atom, a carbon atom, a nitrogen atom, and an oxygen atom. A cross-linking agent composed of a group consisting of a hydroxyl group, an epoxy group, and an alkoxy group having 1 to 5 carbon atoms and a compound having a ring structure. By using such a cross-linking agent, an organic-inorganic mixed resin composition can be realized in which a resin film suitable for a substrate for a flexible device having excellent solvent resistance is excellent in reproducibility and a storage stability is further improved.
Among them, the total number of hydroxyl groups, epoxy groups, and alkoxy groups having 1 to 5 carbon atoms of one of the compounds in the cross-linking agent is preferably 3 from the viewpoint of achieving good reproducibility and achieving solvent resistance of the obtained resin film. From the viewpoint of achieving good reproducibility of the flexibility of the obtained resin film, it is preferably 10 or less, more preferably 8 or less, and still more preferably 6 or less.

Specific examples of the ring structure of the cross-linking agent include aryl rings such as benzene, pyridine, pyrazine, pyrimidine, pyridazine, 1,3,5-triazine and the like containing nitrogen atom-containing aryl heterocycles ( heteroaryl rings), cyclopentane, cyclohexane, cycloheptane and other rings, piperidine, piperazine, hexahydropyrimidine, hexahydropyridazine, hexahydro-1,3,5-triazine and other rings Like amines.

The number of ring structures of one of the compounds in the cross-linking agent is not particularly limited as long as it is 1 or more, but the viewpoint of ensuring the solubility of the cross-linking agent to the solvent and obtaining a flat resin film is preferably 1 or 2.
In addition, when there are two or more ring structures, the ring structures may be condensed with each other, or may be passed through an alkane having 1 to 5 carbon atoms such as methylene, ethylene, propane, and propane-2,2-diyl. The linking group and ring structure of two groups are bonded to each other.

The molecular weight of the cross-linking agent is not particularly limited when it has cross-linking energy and is soluble in the solvent used. The solvent resistance of the obtained resin film, the solubility of the cross-linking agent in organic solvents, ease of acquisition, or price are considered. It is preferably about 100 to 500, more preferably about 150 to 400.

The cross-linking agent may further have a group derived from a hydrogen atom, a carbon atom, a nitrogen atom, and an oxygen atom, such as a keto group and an ester group (bonding).

Preferred examples of the crosslinking agent include compounds represented by any one of the following formulae (K1) to (K5), and one of the preferred aspects of the formula (K4) can be represented by the formula (K4-1) One of the compounds in the preferred embodiment of the formula (K5) includes compounds represented by the formula (5-1).

In the above formula, each of A ¹ and A ² independently of each other represents an alkane having 1 to 5 carbon atoms such as methylene, ethylene, trimethylene, and propane-2,2-diyl. Among the diyl groups, A ^{1 is} preferably a methylene group or an ethylene group, more preferably a methylene group, and A ^{2 is} preferably a methylene group or a propane-2,2-diyl group.

In the formulae (K1) to (K5), each X independently represents a hydroxyl group, an epoxy group (oxe-cyclopropyl group), or a methoxy group, an ethoxy group, a 1-propoxy group, an isopropoxy group, An alkoxy group having 1 to 5 carbon atoms such as 1-butoxy and t-butoxy.
Among them, when considering the availability, price, etc. of the crosslinking agent, X is preferably an epoxy group in the formulae (K1) and (K5), and preferably a carbon atom in the formulae (K2) and (K3) The alkoxy group having a number of 1 to 5 is preferably a hydroxyl group in the formula (K4).

In the formula (K4), each n represents the number of-(A ¹ -X) groups bonded to a benzene ring, and is an integer of 1 to 5 independently, preferably 2 to 3, and more preferably 3.

In each compound, it is preferable that all of A ¹ are the same group, and all of X are the same group.

The compounds represented by the above formulae (K1) to (K5) may be aryl compounds, heteroaryl compounds, cyclic amine skeleton compounds, etc., having a ring structure having the same ring structure as those of these compounds. An oxyalkyl halide compound, an alkoxy halide compound, and the like are obtained by a carbon-carbon coupling reaction or an N-alkylation reaction, or by hydrolyzing an alkoxy moiety of a result.

As the cross-linking agent, a commercially available product may be used, or a compound synthesized by a known synthesis method may be used.
Commercial products include CYMEL (registered trademark) 300, 301, 303LF, 303ULF, 304, 350, 3745, XW3106, MM-100, 323, 325, 327, 328, Same as 385, Same as 370, Same as 373, Same as 380, Same as 1116, Same as 1130, Same as 1133, Same as 1141, Same as 1161, Same as 1168, Same as 3020, Same as 202, Same as 203, Same as 1156, Same as MB-94, Same as MB- 96, the same as MB-98, the same as 247-10, the same as 651, the same as 658, the same as 683, the same as 688, the same as 1158, the same as MB-14, the same as MI-12-I, the same as MI-97-IX, and the same as U-65 , Same UM-15, same U-80, same U-21-511, same U-21-510, same U-216-8, same U-227-8, same U-1050-10, same U-1052 -8, the same U-1054, the same U-610, the same U-640, the same UB-24-BX, the same UB-26-BX, the same UB-90-BX, the same UB-25-BE, and the UB-30 -B, same as U-662, same as U-663, same as U-1051, same as UI-19-I, same as UI-19-IE, same as UI-21-E, same as UI-27-EI, same as U-38 -I, same UI-20-E, same 659, same 1123, same 1125, same 5010, same 1170, same 1172, same as NF3041, same as NF2000 (the above are allnex), TEPIC (registered trademark) V, same as S , Same HP, same L, same PAS, same VL, same UC (the above are made by Nissan Chemical Industry Co., Ltd.), TM-BIP-A (Asahi Organic Materials Industry ( Stock)), 1,3,4,6-tetrakis (methoxymethyl) glycol urea (hereinafter referred to as TMG) (manufactured by Tokyo Chemical Industry Co., Ltd.), 4,4'-methylenebis (N , N-diglycidyl aniline) (made by Aldrich), HP-4032D, HP-7200L, HP-7200, HP-7200H, HP-7200HH, HP-7200HHH, HP-4700, HP-4770, HP-5000 , HP-6000, HP-4710, EXA-4850-150, EXA-4850-1000, EXA-4816, HP-820 (DIC (stock)), TG-G (Shikoku Chemical Industry (stock)), etc.

Preferred examples of the crosslinking agent are listed below, but they are not limited thereto.

The compounding amount of the cross-linking agent is appropriately determined depending on the type of the cross-linking agent, etc., so it cannot be specified generally, but it is usually relative to the mass of the aforementioned polyimide or the total mass of the aforementioned polyimide and the aforementioned inorganic fine particles. From the viewpoint of ensuring the flexibility and fragility of the obtained resin film, it is 50% by mass or less, preferably 100% by mass or less, and from the viewpoint of ensuring the solvent resistance of the obtained resin film, it is 0.1% by mass or more. It is preferably 1% by mass or more.

[(C): Organic solvents]
The organic-inorganic hybrid resin composition of the present invention contains an organic solvent in addition to the aforementioned polyimide, inorganic fine particles modified with a specific alkoxysilane, and any other inorganic fine particles and a crosslinking agent. The organic solvent is not particularly limited, and examples thereof include the same as the specific examples of the reaction solvent used in the preparation of the polyamic acid and the polyimide. More specific examples include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazoline Ketones, N-ethyl-2-pyrrolidone, γ-butyrolactone, and the like. The organic solvents may be used singly or in combination of two or more kinds.
Among these, when a resin film having a high flatness is considered in terms of good reproducibility, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, and γ-butyrolactone are preferred.

[Organic-inorganic mixed resin composition]
The present invention includes (A) inorganic fine particles modified with a specific alkoxysilane, (B) the aforementioned polyimide, and (C) an organic solvent, and other inorganic fine particles containing silicon dioxide and the like, An organic-inorganic mixed resin composition such as a crosslinking agent. Here, the organic-inorganic mixed resin composition of the present invention is homogeneous, and no phase separation is confirmed.
In the organic-inorganic mixed resin composition of the present invention, (A) the inorganic fine particles modified with a specific alkoxysilane surface and the blending ratio of (B) the aforementioned polyimide, and (A) the inorganic fine particles in a mass ratio : (B) Polyfluoreneimine = 10: 1 ~ 1: 10 is more preferable, and 8: 2 ~ 2: 8 is more preferable. For example, it may be 7: 3 ~ 3: 7, or 5: 5 ~ 9: 1. When other inorganic fine particles not modified with a specific alkoxysilane compound are included, the above mass ratio may be considered (A) The mass of the inorganic fine particles includes other inorganic fine particles, but as described above, the specific alkoxysilane is not used. The content of the other inorganic fine particles modified by the compound is a total of 50% by mass to 0% by mass of the inorganic fine particles based on the component (A) of the present case and other inorganic fine particles not modified by the specific alkoxysilane compound. 20% by mass to 0% by mass.
The solid content in the organic-inorganic mixed resin composition of the present invention is usually in the range of 0.5 to 30% by mass, but from the viewpoint of the uniformity of the film, it is preferably 5% to 20% by mass. The solid content means a component remaining after removing the solvent from all the components constituting the organic-inorganic mixed resin composition.
The viscosity of the organic-inorganic mixed resin composition is appropriately determined in consideration of the coating method to be used and the thickness of the resin film to be produced, but it is usually 1 to 50,000 mPa ･ s at 25 ° C.

In the organic-inorganic mixed resin composition of the present invention, various organic or inorganic low-molecular or high-molecular compounds may be added in order to impart processing characteristics or various functions. For example, a catalyst, an antifoaming agent, a flattening agent, a surfactant, a dye, a plasticizer, a fine particle, a coupling agent, a sensitizer, and the like can be used. For example, the catalyst can be added for the purpose of reducing the retardation or the coefficient of linear expansion of the resin film.
The organic-inorganic mixed resin composition of the present invention is a polyimide obtained by the above method, the inorganic fine particles modified on the surface with a specific alkoxysilane compound, other inorganic fine particles such as desired silicon dioxide, and a crosslinking agent. It can be obtained by dissolving in the above-mentioned organic solvent. In the reaction solution prepared by polyimide, the above-mentioned inorganic fine particles modified with a specific alkoxysilane compound or a solution thereof can be added, and silicon dioxide can be added as desired. , A cross-linking agent, etc., the aforementioned organic solvent may be further added as desired.

[Resin film and substrate for flexible device]
The organic-inorganic mixed resin composition of the present invention described above is applied to a substrate, and the organic solvent is removed by drying and heating, and excellent heat resistance, low delay, excellent softness, and excellent transparency (high Light transmittance: for example, a light transmittance of more than 80% at 400nm, low yellowness: for example, a haze value of less than 2%), a resin film, and excellent performance in maintaining these properties can be obtained while being mechanically peeled off Resin film that can be peeled from the release layer and can be used as a substrate for a flexible device.
In addition, the resin film formed of the organic-inorganic mixed resin composition and the substrate for flexible devices, that is, the polyimide and the inorganic fine particles modified on the surface with a specific alkoxysilane compound, and desired A substrate for a flexible device containing inorganic fine particles such as silicon dioxide, a cross-linking agent, etc., that is, a substrate for a flexible device made of a cured product of the organic-inorganic hybrid resin composition of the present invention is also a feature of the present invention. Object.

Examples of the substrate used in the production of a flexible device substrate (resin film) include plastics (polycarbonate, polymethacrylate, polystyrene, polyester, polyolefin, epoxy, melamine, and three Acetyl cellulose, ABS, AS, norbornene resin, etc.), metal, stainless steel (SUS), wood, paper, glass, silicon wafer, slate, etc.
Especially when it is used as a substrate for a flexible device, it can be used from the viewpoint of existing equipment. The substrate used is preferably glass or silicon wafer, and the obtained substrate for a flexible device exhibits good peelability. It is more preferably glass. The coefficient of linear expansion of the substrate used is preferably 40 ppm / ° C or less, more preferably 30 ppm / ° C or less, from the viewpoint of warpage of the substrate after coating.

When forming a release layer on a base material, a conventional method may be used. That is, a known release layer-forming composition containing an aromatic polyfluorene imide, polybenzoxazole, or the like is applied to a substrate, and then fired at a temperature exceeding 450 ° C. by a conventional method. A release layer can be formed on the substrate. As these, for example, International Publication No. 2017/204178, International Publication No. 2017/204182, International Publication No. 2017/204186, and the like can be used as the composition for release layer formation, the composition described in the release layer, and the release layer.

The coating method of the organic-inorganic mixed resin composition on the substrate or the release layer formed on the substrate is not particularly limited, and examples thereof include a casting coating method, a spin coating method, a doctor blade coating method, and a dip coating. Method, roll coating method, bar coating method, die coating method, inkjet method, printing method (letter plate, gravure, lithography, screen printing, etc.), etc., these coating methods can be suitably used depending on the purpose.

The heating temperature is preferably 350 ° C or lower. When it exceeds 350 ° C., the obtained resin film becomes brittle, and a resin film particularly suitable for a display substrate application may not be obtained in some cases.
In addition, when considering the heat resistance and linear expansion coefficient characteristics of the obtained resin film, the organic-inorganic mixed resin composition after coating is heated at 40 ° C to 100 ° C for 5 minutes to 2 hours. Raise the heating temperature, and finally heat it for more than 175 ° C to 350 ° C for 30 minutes to 2 hours. In this way, by heating at a temperature of two or more stages, that is, the stage where the solvent is dried and the stage where the molecular alignment is promoted, reproducibility is better, and low thermal expansion characteristics are exhibited.
In particular, the coated organic-inorganic mixed resin composition is heated at 40 ° C to 100 ° C for 5 minutes to 2 hours, and then heated at more than 100 ° C to 175 ° C for 5 minutes to 2 hours, followed by more than 175 ° C to It is better to heat at 350 ° C for 5 minutes to 2 hours.
Examples of the appliance used for heating include a hot plate and an oven. The heating environment can be under air, or under an inert gas such as nitrogen, or under normal pressure, or under reduced pressure, and different pressures can be used in each stage of heating.

The thickness of the resin film is in the range of about 1 to 200 μm, and the type of the flexible device can be considered as appropriate. Especially if it is used as a substrate for a flexible display, it is usually about 1 to 60 μm, preferably About 5-50 μm, adjust the thickness of the coating film before heating to form a resin film with a desired thickness.
The method of peeling the resin film formed in this manner from the substrate is not particularly limited, and a method of cooling the resin film together with the substrate, cutting the film, peeling it, or peeling it off by applying tension through a roller, and the like.

The thus obtained resin film in one of the preferred aspects of the present invention can achieve high transparency with a light transmittance of more than 80% at 400 nm and a light transmittance of 90% or more at a wavelength of 550 nm. Low yellowness with a haze value of 1.5% or less.
The resin film may have, for example, a linear expansion coefficient of 50 ppm to 200 ° C or lower, particularly a low value of 5 ppm / ° C to 25 ppm / ° C, and excellent dimensional stability during heating.
The resin film has birefringence when the wavelength of incident light is 590 nm, that is, two birefringences when viewed from a cross section in the thickness direction (the refractive index of two in the plane and the refractive index in the thickness direction). Each difference) is characterized in that the thickness direction retardation R _th represented by the average value of the two phase differences obtained by multiplying the film thickness is small.

Since the resin film described above has the above-mentioned characteristics, those that satisfy various conditions necessary as a base film of a flexible device substrate are particularly suitable for use as a base film of a flexible device, particularly a flexible display substrate.

In another aspect of the present invention, a method for manufacturing a substrate for a flexible device is provided.
Since this method has the following steps, a substrate for a flexible device can be obtained.
a) a step of forming a release layer on a supporting substrate such as a glass substrate;
b) a step of forming a resin film to be a substrate for a flexible device using the organic-inorganic hybrid resin composition of the present invention on the release layer; and
c) A step of peeling the resin film from the release layer to obtain a substrate for a flexible device.
As shown in FIG. 1, the step c) is a step of peeling the resin film at an interface between a release layer (De-Bonding Layer) and a resin film (PI / silicon dioxide film) serving as a flexible device substrate.
The above-mentioned release layer can be formed by a composition containing a known release layer such as the aromatic polyfluoreneimide, polybenzoxazole, or the like.

[Example]

Examples are given below to describe the present invention in more detail, but the present invention is not limited to the following examples.

The meanings of the abbreviations used in the following examples are as follows.

<Acid dianhydride>
BODAxx: Bicyclic [2,2,2] octane-2,3,5,6-tetracarboxylic dianhydride
CBDA: 1,2,3,4-cyclobutane tetracarboxylic dianhydride
PMDA: pyromellitic dianhydride

＜ Diamine ＞
TFMB: 2,2'-bis (trifluoromethyl) benzidine
p-PDA: p-phenylenediamine

＜ Organic solvents ＞
GBL: γ-butyrolactone
NMP: N-methyl-2-pyrrolidone

In the examples, the equipment and conditions used for the preparation of samples and the analysis and evaluation of physical properties are as follows.
1) Measurement of number average molecular weight and weight average molecular weight The number average molecular weight of the polymer (hereinafter referred to as Mn) and weight average molecular weight (hereinafter referred to as Mw) are based on devices: Showa Denko Corporation, Showdex GPC-101, tube Column: KD803 and KD805, column temperature: 50 ° C, dissolution solvent: DMF, flow rate: 1.0ml / min, calibration line: standard polystyrene measurement.
2) The film thickness of the resin film obtained is measured with a thickness gauge made by Teclock Corporation.
3) Coefficient of linear expansion (CTE)
Using TMA Q400 manufactured by TA instruments, the film was cut to a size of 5 mm in width and 16 mm in length. First, the temperature was raised at 10 ° C / min, and the temperature was increased from 50 to 350 ° C (first heating). Then, the temperature was lowered at 10 ° C / min. After cooling to 50 ° C, the temperature was raised at 10 ° C / min. When heating from 50 to 420 ° C (second heating), the linear expansion coefficient (CTE [ppm / ° C) from 50 ° C to 200 ° C was measured for the second heating. ]). A load of 0.05 N was added by the first heating, cooling, and second heating.
4) Thermal decomposition temperature 5% weight reduction temperature (Td _5% )
The 5% weight reduction temperature (Td _5% [° C]) was measured using TGA Q500, manufactured by TA instruments, in a nitrogen film at a temperature of about 5 to 10 mg, and the temperature was raised from 50 ° C to 800 ° C at 10 ° C / min. Find it.
5) Light transmittance (transparency) (T _400nm , T _550nm ) and CIE b value (CIE b ^* )
The light transmittance (T _400nm , T _550nm [%]) and CIE b value (CIE b ^* ) of the wavelengths of 400nm and 550nm are using SA4000 spectrometer manufactured by Nippon Denshoku Industries Co., Ltd. Measure for reference.
6) Delay (R _th )
The thickness direction retardation (R _th ) was measured at room temperature using KOBURA 2100ADH, manufactured by Oji Measurement Co., Ltd.
The thickness direction retardation (R _th ) is calculated using the following formula.
R _th = [(Nx + Ny) / 2-Nz] × d = [(ΔNxz × d) + (ΔNyz × d) / 2
Nx, Ny: two refractive indices orthogonal in the plane (Nx> Ny, Nx is called the slow axis, Ny is called the fast axis)
Nz: refractive index in the thickness (vertical) direction with respect to the surface
d: film thickness ΔNxy: difference between two refractive indices in the plane (Nx-Ny) (birefringence)
ΔNxz: the difference between the refractive index Nx in the plane and the refractive index Nz in the thickness direction (birefringence)
ΔNyz: the difference between the refractive index Ny in the plane and the refractive index Nz in the thickness direction (birefringence)
7) Polyimide is dried using a Drv 320 vacuum oven made by ADVANTEC.

[1] Synthesis example Synthesis example 1: Synthesis of polyimide A (PI-A) and preparation of 7wt% solution

In a 250 mL reaction three-necked flask equipped with a nitrogen injection port / exhaust port, a mechanical stirrer and a cooler, 25.6 g (0.08 mol) of TFMB was added. Then, 173 g of GBL was added, and stirring was started. After the diamine was completely dissolved in the solvent, 10.0 g (0.04 mol) of BODAxx, 7.84 g (0.04 mol) of CBDA and 43.4 g of GBL were added after stirring, and heated to 140 ° C. under nitrogen. Then, 0.35 g of 1-ethylpiperidine was added to the solution, and heated to 180 ° C. for 7 hours under nitrogen. Finally, the heating was stopped, the reaction solution was diluted to 10%, and stirring was maintained overnight. The polyfluorene imine reaction solution was added to 2000 g of GBL: methanol = 50wt%: 50wt% mixed solution, and after stirring for 30 minutes, the polyfluorene imide was filtered to purify the polyfluorene imine. Then, the polyimide solid was stirred in 2000 g of methanol for 30 minutes, and the polyimide solid was filtered. The purification sequence of the polyimide solid was stirred and filtered three times. After drying in a vacuum oven at 150 ° C. for 8 hours, the methanol residue in the polyimide was removed, and finally 21.5 g of the polyimide A was obtained after drying. The yield of polyimide A (PI-A) was 51% (Mw = 310,000, Mn = 144,300). This PI-A7g was put in a 500 mL Erlenmeyer flask, and after adding GBL93g, it stirred at room temperature for 4 days to obtain a 7 wt% polyimide GBL solution (PI-B).

Synthesis Example 2: Synthesis of Varnish (DBL-1) for release layer 1.02 g (9.5 mmol) of p-PDA was dissolved in 26.4 g of NMP. 2.58 g (11.8 mmol) of PMDA was added to the obtained solution, and a reaction was performed at 23 ° C. for 24 hours under a nitrogen atmosphere. Then, 0.44 g (4.7 mmol) of aniline was added, and the reaction was further performed for 24 hours. The obtained polymer had an Mw of 31,500 and a molecular weight distribution of 3.2. NMP23g was added to this solution, and it stirred at room temperature for 24 hours, and obtained the varnish (DBL-1) for peeling layers.

[2] Preparation example Preparation example 1: Preparation of a 500 mL reaction three-necked flask containing a nitrogen dioxide-modified silicon dioxide particle solution (Si-1) at a nitrogen inlet and outlet and a cooler Inside, add 200g (13.3%) of Quartron PL-1-IPA (manufactured by Fuso Chemical Industry Co., Ltd., registered trademark, particle size (specific surface area conversion) 10-15nm, dispersing medium isopropanol), and 4-biphenyl Trimethoxysilane 1.644 g. Then, it heated at 100 degreeC for 17 hours in nitrogen atmosphere. After the reaction was completed, 79.8 g of GBL was added, and isopropyl alcohol was distilled off under reduced pressure using an evaporator to obtain a GBL sol solution (Si-1) of silica particles modified with a specific alkoxysilane. 1 g of this solution was heated on an aluminum cup at 200 ° C. for 2 hours, and the concentration was calculated from the residual amount, and the concentration was 35% by weight.

Preparation Example 2: Preparation of a solution containing modified silicon dioxide particles (Si-2) with a specific alkoxysilane. A 100-mL reaction three-necked flask equipped with a nitrogen inlet / outlet and a cooler was charged with Quartron. PL-1-IPA (manufactured by Fuso Chemical Industry Co., Ltd., registered trademark, particle size (specific surface area conversion) 10 to 15 nm, dispersion medium isopropanol) 50 g (13.3%) and 4-biphenyltrimethoxysilane 0.206 g. Then, it heated at 100 degreeC for 22 hours in nitrogen environment. After the reaction was completed, 19.9 g of GBL was added, and isopropyl alcohol was distilled off under reduced pressure using an evaporator to obtain a GBL sol solution (Si-2) of silica particles modified with a specific alkoxysilane. 1 g of this solution was heated on an aluminum cup at 200 ° C. for 2 hours, and the concentration was calculated from the residual amount, and the concentration was 35% by weight.

Preparation Example 3: Preparation of a solution containing silicon dioxide particles modified with alkoxysilane (Si-3) In a 500 mL reaction three-necked flask equipped with a nitrogen inlet / outlet and a cooler, Quartron PL was added -1-IPA (manufactured by Fuso Chemical Industry Co., Ltd., registered trademark, particle size (specific surface area conversion) 10-15nm, dispersion medium isopropanol) 200g (13.3%) and 1.13g of phenyltrimethoxysilane. Then, it heated at 100 degreeC for 17 hours in nitrogen atmosphere. After the reaction was completed, 79.8 g of GBL was added, and isopropyl alcohol was distilled off under reduced pressure using an evaporator to obtain a GBL sol solution (Si-3) of silicon dioxide particles modified with alkoxysilane. 1 g of this solution was heated on an aluminum cup at 200 ° C. for 2 hours, and the concentration was calculated from the residual amount, and the concentration was 35% by weight.

Preparation example 4: Preparation of a solution containing silicon dioxide particles (Si-4) In a 500 mL eggplant-shaped flask, Quartron PL-1-IPA (made by Fuso Chemical Industry Co., Ltd., registered trademark, particle size (specific surface area conversion)) 10 ~ 15nm, isopropanol (dispersion medium) 200g (13.3%) and GBL 79.8g, isopropyl alcohol was distilled off under reduced pressure using an evaporator to obtain a GBL sol solution (Si of non-modified silicon dioxide particles of alkoxysilane) -4). 1 g of this solution was heated on an aluminum cup at 200 ° C. for 2 hours, and the concentration was calculated from the residual amount, and the concentration was 35% by weight.

[3] Formation of release layer Using a spin coater (condition: 3,000 rpm, about 30 seconds), the varnish (DBL-1) for the release layer obtained in Synthesis Example 2 was applied to a glass substrate of 100 mm × 100 mm Glass substrate (the same applies hereinafter).
Then, the obtained coating film was heated at 80 ° C for 10 minutes using a hot plate, and then heated at 300 ° C for 30 minutes using an oven, and the heating temperature was raised (10 ° C / minute) to 500 ° C, and then heated at 500 ° C for 10 minutes. A release layer having a thickness of about 0.1 μm was formed on the glass substrate. During the temperature rise, the substrate with the film was not removed from the oven, but was heated in the oven.

[4] Preparation of composition and formation of thin film Example 1
To 10 g of the 7 wt% polyfluorene imine GBL solution (PI-B) obtained in Synthesis Example 1 was added 4.66 g containing a specific alkoxysilane modified silicon dioxide particle solution (Si-1) and GBL 3.27 g, Stir at room temperature for 3 days. Then, it filtered through a 0.45 micrometer propylene filter, and obtained the objective varnish (organic-inorganic mixed resin composition). The obtained varnish was applied on a release layer with a coating bar (gap of 250 microns), and heated at 100 ° C. for 1 hour using a hot plate. It was heated on a hot plate at 280 ° C for 30 minutes to obtain a transparent PI film L1. The L1 system is easily peeled from the release layer as shown in FIG. 1. The optical and thermal characteristics of L1 are shown in Table 1.

Example 2
A varnish (organic-inorganic mixed resin composition) was obtained in the same manner as in Example 1, except that the above-mentioned (Si-1) was replaced with a solution containing 4.66 g of a silica particle modified with specific alkoxysilane (Si-2). . The coating was applied on the release layer to form a thin film to obtain a transparent PI film L2. L2 is similar to L1 and can be easily peeled from the peeling layer. The optical and thermal characteristics of L2 are shown in Table 1.

Example 3
To 10 g of the 7 wt% polyimide GBL solution (PI-B) obtained in Synthesis Example 1, 3.00 g and 0.46 g of GBL containing a solution (Si-1) modified with specific alkoxysilanes were added. Stir at room temperature for 3 days. Then, it filtered through a 0.45 micrometer propylene filter, and obtained the objective varnish (organic-inorganic mixed resin composition). The obtained varnish was applied to the release layer with a coating bar (250 micrometer gap), and heated at 100 ° C. for 1 hour using a hot plate. The furnace KDF-900GL (manufactured by Denken) was replaced with a vacuum gas under a nitrogen environment, and the heating temperature was raised (10 ° C / min) to 350 ° C, and then heated at 350 ° C for 30 minutes on a hot plate to obtain a transparent PI film L3. The L3 system can be easily peeled from the peeling layer as shown in FIG. 1. The optical and thermal characteristics of L3 are shown in Table 1.

Comparative Example 1
To 10 g of the 7 wt% polyimide GBL solution (PI-B) obtained in Synthesis Example 1 was added 4.66 g of a solution containing silicon dioxide particles modified with an alkoxysilane (Si-3) and 3.27 g of GBL. Stir at warm for 3 days. Then, it was filtered through a 0.45 micron propylene filter to obtain the intended varnish. The obtained varnish was applied to the release layer with a coating bar (250 micrometer gap), and heated at 100 ° C. for 1 hour using a hot plate. However, the varnish shrinks during heating and drying, and a film cannot be obtained.

Comparative Example 2
To 10 g of a 7 wt% polyfluorene imine GBL solution (PI-B) obtained in Synthesis Example 1, 4.66 g of a solution containing silicon dioxide particles (Si-4) and 3.27 g of GBL were added, and the mixture was stirred at room temperature for 3 days. Then, it was filtered through a 0.45 micron propylene filter to obtain the intended varnish. The obtained varnish was applied on an alkali-free glass substrate with a coating rod (250 micrometer gap), and heated at 100 ° C. for 1 hour using a hot plate. It was heated on a hot plate at 280 ° C for 30 minutes to obtain a transparent PI film HL2. This film was attempted to be peeled in the same manner as in FIG. 1, but it could not be peeled at all and cracks occurred.

Comparative Example 3
To 10 g of a 7 wt% polyfluorene imine GBL solution (PI-B) obtained in Synthesis Example 1, 4.66 g of a solution containing silicon dioxide particles (Si-4) and 3.27 g of GBL were added, and the mixture was stirred at room temperature for 3 days. Then, it was filtered through a 0.45 micron propylene filter to obtain the intended varnish. The obtained varnish was applied to a release laminate with a coating bar (250 micrometer gap), and heated at 100 ° C. for 1 hour using a hot plate. It was heated on a hot plate at 280 ° C for 30 minutes to obtain a transparent PI film HL3. This film was attempted to be peeled in the same manner as in FIG. 1, but it could not be peeled at all and cracks occurred.

Comparative Example 4
10 g of a 7 wt% polyfluorene imine GBL solution (PI-B) obtained in Synthesis Example 1 was applied to a release laminate with a coating bar (gap of 500 μm), and heated at 100 ° C. for 1 hour using a hot plate. It was heated on a hot plate at 280 ° C for 30 minutes to obtain a transparent PI film HL4. HL4 is shown in Figure 1 and can be peeled from the peeling layer. The optical and thermal characteristics of HL4 are shown in Table 1.

As shown in Table 1, the films L1 to L3 obtained in the examples can be easily peeled from the release layer, show self-supporting properties, and exhibit excellent optical characteristics and low CTE. In Comparative Examples 1 to 3, a self-supporting film could not be obtained. In addition, Comparative Example 4, which can obtain a self-supporting film, shows a high retardation value. Compared to the embodiment, the light transmittance is lower. The yellowness indicated by the CIE b ^* value is higher. Also, compared with the embodiment, , Showing higher CTE results.

[Fig. 1] A schematic diagram of a method for peeling a substrate for a flexible device obtained from the organic-inorganic mixed resin composition of the present invention from a supporting substrate.

Claims (12)

An organic-inorganic mixed resin composition comprising an organic-inorganic mixed resin composition including the following (A) component, (B) component, and (C) component, (A) Component: The average particle diameter of the surface of the modified microparticles is modified by an alkoxysilane compound having two aromatic groups having 6 to 18 carbon atoms or 1 aromatic group having 7 to 18 carbon atoms. 100nm inorganic fine particles, (B) component: polyfluorene imine having fluorine, (C) component: organic solvent. The organic-inorganic mixed resin composition according to claim 1, wherein the alkoxysilane compound in the component (A) is a compound represented by the following formula (S1), (Wherein R ¹ and R ² are each independently an alkyl group having 1 to 3 carbon atoms, W is an integer of 1 to 3, Y is an integer of 0 to 2 and W + Y = 3, and Z ¹ represents a group selected from A group consisting of a halogen atom, an alkyl group having 1 to 10 carbon atoms, and an alkoxy group having 1 to 10 carbon atoms, m represents an integer of 0 to 5, but when m is an integer of 2 or more, Z ¹ may be The same or different basis). The organic-inorganic mixed resin composition according to claim 1 or 2, wherein m is 0 in the foregoing formula. The organic-inorganic mixed resin composition according to any one of claims 1 to 3, wherein the polyimide of the component (B) is a tetracarboxylic dianhydride component and contains a fluorine-containing aromatic compound represented by the following formula (A1) Polyimide sulfonium imide of the reaction product of diamine and diamine component, (In the formula, B ² represents a divalent group selected from the group consisting of formulas (Y-1) to (Y-34).) (In the formula, * represents a bond key). The organic-inorganic mixed resin composition according to claim 4, wherein the tetracarboxylic dianhydride component includes an alicyclic tetracarboxylic dianhydride represented by the following formula (C1), [In the formula, B ¹ represents a 4-valent group selected from the group consisting of formulas (X-1) to (X-12), (In the formula, plural Rs independently represent a hydrogen atom or a methyl group, and * represents a bonding bond)]. The organic-inorganic mixed resin composition according to any one of claims 1 to 5, wherein the inorganic fine particles of the component (A) are silica particles. The organic-inorganic mixed resin composition according to any one of claims 1 to 6, wherein the mass ratio (A) :( B) of the aforementioned (A) component to (B) component is 5: 5 to 9: 1. The organic-inorganic mixed resin composition according to any one of claims 1 to 7, wherein the inorganic fine particles of the component (A) are inorganic fine particles having an average particle diameter of 1 nm to 60 nm. The organic-inorganic mixed resin composition according to any one of claims 1 to 8, wherein the component (C) is an ester-based solvent. A resin film formed of the organic-inorganic mixed resin composition according to any one of claims 1 to 9, having a light transmittance of more than 80% at 400 nm, transparent, and having a haze of 2% or less. A substrate for a flexible device, which is made of a resin film according to claim 10. A method for manufacturing a flexible device substrate includes the following steps: a) a step of forming a release layer on the supporting substrate; b) on the release layer, a step of forming a resin film made of the organic-inorganic mixed resin composition according to any one of claims 1 to 9 to be a substrate for a flexible device; and c) A step of peeling the resin film from the release layer to obtain a substrate for a flexible device.