KR20220098403A - Polyimide precursor resin composition - Google Patents

Abstract

{식 중, R₁ 은, 복수 있는 경우 각각 독립적으로 2 가의 유기기를 나타내고, R₂ 는, 복수 있는 경우 각각 독립적으로 4 가의 유기기를 나타내고, n 은 양의 정수이다.} 로 나타내는 구조를 갖는 폴리이미드 전구체와, 용매를 포함하는 수지 조성물로서, 상기 폴리이미드 전구체의 중량 평균 분자량이 110,000 ∼ 250,000 이고, 상기 수지 조성물의 고형분 함유량이 10 ∼ 25 질량％ 인, 수지 조성물이 제공된다.Equation (1):

{wherein, when there are a plurality of R ₁ , each independently represents a divalent organic group, R ₂ each independently represents a tetravalent organic group when there is a plurality, and n is a positive integer.} As a resin composition containing a mid precursor and a solvent, the weight average molecular weight of the said polyimide precursor is 110,000-250,000, and the resin composition whose solid content of the said resin composition is 10-25 mass % is provided.

Description

Polyimide precursor resin composition {POLYIMIDE PRECURSOR RESIN COMPOSITION}

The present invention relates to a resin composition containing a polyimide precursor, and a polyimide film. The present invention also relates to flexible devices (eg flexible displays) and laminates and methods of making them.

Polyimide resin is an insoluble, infusible, superheat-resistant resin, and has excellent properties such as heat resistance (eg, thermal oxidation resistance), radiation resistance, low temperature resistance, and chemical resistance. For this reason, polyimide resin is used in the wide field including an electronic material. As an application example of the polyimide resin in the field of electronic materials, an insulating coating material, an insulating film, a semiconductor, the electrode protective film of a thin film transistor liquid crystal display (TFT-LCD), etc. are mentioned, for example. In recent years, instead of the glass substrate used conventionally in the field|area of a display material, adoption of the flexible board|substrate using the lightness and flexibility is examined.

For example, Patent Document 1 describes a resin precursor (weight average molecular weight of 30,000 to 90,000) that is polymerized from bis(diaminodiphenyl)sulfone (hereinafter also referred to as DAS) and has a siloxane unit, and the precursor is Polyimide obtained by curing has a low residual stress generated between a support such as glass, excellent chemical resistance, and has a small effect on yellowness (YI) value and total light transmittance due to oxygen concentration during the curing process. that is described. In addition, Patent Document 2 describes a resin composition comprising a polyimide precursor having a specific absorbance and an alkoxysilane compound having a specific absorbance, and the resin obtained by curing the resin composition has sufficient adhesiveness and , which makes releasability by laser peeling or the like compatible.

International Publication No. 2014/148441 International Publication No. 2016/167296

When a transparent polyimide resin is to be applied to a flexible substrate, a resin composition containing a polyimide precursor is applied on a substrate such as glass to form a coating film, and then this is heat-dried, and the polyimide precursor is further imidized After forming a device on the film as necessary, the film is peeled off from a support, such as a glass substrate, to obtain a target product.

In recent years, when apply|coating the composition containing a polyimide precursor to board|substrates, such as glass, with enlargement of the display etc. which are uses of a flexible substrate, a slit coater may be used. When the composition is applied with a slit coater to form a coating film, as a parameter affecting the coating film, there is a coater gap (a setting value that defines the distance between the glass substrate and the slit nozzle). If the coater gap is small, the flatness of the glass substrate In this bad case, the nozzle may contact the substrate and the slit nozzle may be damaged. In particular, with the recent increase in size of displays and the like, it has become necessary to sufficiently enlarge this coater gap.

In addition, when a polyimide film is used as a material for a screen of a flexible display or the like, since the wavelength of visible light is about 380 nm to about 700 nm, particularly high film thickness uniformity is required in order to obtain good optical performance.

When the present inventors evaluated the coating of a slit coat using the polyimide precursor which has the same molecular weight and frame|skeleton as that described in the said patent documents 1 and 2, it discovered that the said characteristic was inadequate. Therefore, one aspect of the present invention aims to provide a polyimide precursor-containing resin composition that is excellent in the coating properties of the slit coat and also excellent in mechanical properties and optical properties required for applications such as flexible substrates.

MEANS TO SOLVE THE PROBLEM The present inventors discovered that using the polyimide precursor which has a specific structure brought about the realization of the favorable coating property in a slit coat, and favorable mechanical property and optical property, as a result of earnestly examining.

That is, the present invention includes the following aspects.

[1] The following formula (1):

[Formula 1]

{wherein, when there are a plurality of R ₁ , each independently represents a divalent organic group, R ₂ each independently represents a tetravalent organic group when there is a plurality, and n is a positive integer.} A resin composition comprising a mid precursor and a solvent,

The polyimide precursor has a weight average molecular weight of 110,000 to 250,000,

The resin composition whose solid content of the said resin composition is 10-25 mass %.

[2] The resin composition according to Aspect 1, wherein the shear rate dependence (TI) expressed by the following formula when the viscosity of the resin composition is measured at 23°C with a viscometer equipped with a temperature controller is 0.9 to 1.1.

TI = ηa/ηb

{wherein, ηa (mPa·s) is the viscosity at the measured rotational speed a (rpm) of the resin composition, and ηb (mPa·s) is the viscosity at the measured rotational speed b (rpm) of the resin composition, However, a * 10 = b.}

[3] The resin composition according to Aspect 1 or 2, wherein the resin composition is a resin composition for slit coat.

[4] At least one of R ₁ in the formula (1) is represented by the following formula (2):

[Formula 2]

The resin composition in any one of said aspects 1-3 which is group represented by.

[5] The polyimide precursor is the following formula (3):

[Formula 3]

{wherein, each of R ₃ and R ₄ , when there is a plurality, each independently represents a monovalent aliphatic hydrocarbon group having 1 to 5 carbon atoms or a monovalent aromatic group having 6 to 10 carbon atoms, and m is 1 to 200 is an integer of.} The resin composition according to any one of Aspects 1 to 4, wherein the resin composition has a structure represented by .

[6] The resin composition according to any one of Aspects 1 to 5, wherein the polyimide precursor is a copolymer of tetracarboxylic dianhydride containing pyromellitic dianhydride and diamine.

[7] Any one of said aspects 1-6 in which the said polyimide precursor is a copolymer of tetracarboxylic dianhydride containing 3,3',4,4'-biphenyltetracarboxylic dianhydride, and diamine The resin composition described in.

[8] The polyimide precursor is a copolymer of tetracarboxylic dianhydride and diamine, and the tetracarboxylic dianhydride is pyromellitic dianhydride and 3,3',4,4'-biphenyltetra The said aspect 1 which contains carboxylic dianhydride in the molar ratio 20:80-80:20 of the said pyromellitic dianhydride and the said 3,3',4,4'- biphenyltetracarboxylic dianhydride The resin composition as described in any one of 7.

[9] The polyimide precursor is tetracarboxylic dianhydride, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 2,2'-bis(trifluoromethyl ) The resin composition according to any one of Aspects 1 to 8, which is a copolymer of at least one diamine selected from the group consisting of benzidine and 9,9-bis(4-aminophenyl)fluorene.

[10] The resin composition according to any one of Aspects 1 to 9, wherein the polyimide precursor has a weight average molecular weight of 160,000 to 220,000.

[11] The resin composition according to any one of Aspects 1 to 10, wherein the resin composition is a resin composition for flexible devices.

[12] The resin composition according to any one of Aspects 1 to 11, wherein the resin composition is a resin composition for a flexible display.

[13] A polyimide film which is a cured product of the resin composition according to any one of Aspects 1 to 12.

[14] The polyimide film according to Aspect 13, wherein the thickness direction retardation (Rth) in terms of a film thickness of 10 µm is 300 or less, and/or the yellowness (YI) in terms of a film thickness of 10 µm is 20 or less. .

[15] A flexible device comprising the polyimide film according to Aspect 13 or 14.

[16] A flexible display comprising the polyimide film according to Aspect 13 or 14.

[17] The flexible display according to Aspect 16, wherein the polyimide film is disposed at a position visually recognized when the flexible display is observed from the outside.

[18] A coating step of applying the resin composition according to any one of Aspects 1 to 12 on the surface of the support;

A film forming step of heating the resin composition to form a polyimide film;

The manufacturing method of the polyimide film including the peeling process of peeling the said polyimide film from the said support body.

[19] The method for producing a polyimide film according to Aspect 18, wherein the coating step includes slit coating the resin composition.

[20] At least one of R ₁ in the formula (1) is represented by the following formula (2):

[Formula 4]

A method for producing a polyimide film according to Aspect 19, which is a group represented by .

[21] The polyimide precursor, the following formula (3):

[Formula 5]

{wherein, each of R ₃ and R ₄ , when there is a plurality, each independently represents a monovalent aliphatic hydrocarbon group having 1 to 5 carbon atoms or a monovalent aromatic group having 6 to 10 carbon atoms, and m is 1 to 200 is an integer of.} The method for producing a polyimide film according to Aspect 19 or 20, which has a structure represented by .

[22] The method for producing a polyimide film according to any one of Aspects 18 to 21, further comprising an irradiation step of irradiating a laser to the polyimide film from the support side prior to the peeling step.

[23] A coating step of applying the resin composition according to any one of Aspects 1 to 12 on the surface of the support;

A film forming step of heating the resin composition to form a polyimide film;

an element forming step of forming an element on the polyimide film;

and a peeling step of peeling the polyimide film on which the element is formed from the support.

[24] The method for producing a display according to Aspect 23, wherein the application step includes slit-coating the resin composition.

[25] The method for manufacturing a display according to Aspect 23 or 24, wherein the polyimide film is disposed at a position visually recognized when the display is observed from the outside.

ADVANTAGE OF THE INVENTION According to one aspect of this invention, while being excellent in the coating characteristic in a slit coat, it becomes possible to provide the polyimide precursor containing resin composition excellent also in the mechanical characteristic and optical characteristic required for uses, such as a flexible substrate.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure above the polyimide board|substrate of a top emission type flexible organic electroluminescent display as an example of the display provided by one aspect|mode of this invention.

DESCRIPTION OF EMBODIMENTS Hereinafter, exemplary embodiments of the present invention (hereinafter, abbreviated as "embodiments") will be described in detail. In addition, this invention is not limited to the following embodiment, It can variously deform and implement within the range of the summary. In addition, unless otherwise specified, the characteristic value described in the present disclosure is intended to be a value measured by a method understood by those skilled in the art that is equivalent to the method described in the section of [Examples] or equivalent thereto.

This embodiment is

Equation (1):

[Formula 6]

{Wherein, when there are a plurality of R ₁ , each independently represents a divalent organic group, R ₂ each independently represents a tetravalent organic group when there is a plurality, and n is a positive integer.}

A resin composition comprising a polyimide precursor having a structure represented by is provided. One aspect WHEREIN: The said resin composition contains the said polyimide precursor and a solvent.

In a preferable aspect, at least ₁ of R<1> in Formula (1) is following formula (2):

[Formula 7]

is a group represented by

It contributes to the favorable optical characteristic (particularly Rth) and heat resistance of the polyimide which is a hardened|cured material of a polyimide precursor that at least ₁ of R<1> in Formula (1) is a structure represented by Formula (2). One aspect WHEREIN: All n pieces of R< ₁ > in Formula (1) have a structure shown by Formula (2). Moreover, in one aspect, the ratio of the structure represented by Formula (2) among n pieces of R< ₁ > in Formula (1) may be 0 % or more, or 10 % or more, or 20 % or more, 100 % or less, or 90 %. % or less.

This embodiment is also a resin composition containing the polyimide precursor which has a structure represented by said Formula (1), Comprising: The polyimide which is hardened|cured material of the said resin composition has thickness direction retardation (Rth) 300 or less and/or yellowness A resin composition having (YI) 20 or less is also provided. The low thickness direction retardation (Rth) indicates that the polyimide has low birefringence, and the low yellowness (YI) indicates that the polyimide has a good color tone (that is, almost colorless). .

The resin composition of this embodiment has the excellent slit-coat performance, and the point which provides the polyimide film which has the outstanding mechanical property and optical characteristic, Preferably it is for flexible devices (for example, for flexible substrates), especially Preferably, it is useful as an object for a flexible display.

(weight average molecular weight of polyimide precursor)

In one aspect, the weight average molecular weight of the polyimide precursor is 110,000 or more and 250,000 or less. When this inventor used the resin composition of this embodiment for a slit coat, it discovered that the weight average molecular weight of a polyimide precursor had a large influence on coating performance, and repeated earnest examination. As a result, it was found that, when the weight average molecular weight of the polyimide precursor is 110,000 or more, a good slit coat can be realized by adjusting the solid content of the resin composition, while a polyimide precursor having a weight average molecular weight of 250,000 or less is easy to manufacture. . That is, in this embodiment, the weight average molecular weight of a polyimide precursor is 110,000 or more from a viewpoint of coating performance, and is 250,000 or less from a viewpoint of manufacturing easiness.

The preferable weight average molecular weight of a polyimide precursor may differ with a desired use, the kind of polyimide precursor, solid content of a resin composition, the kind of solvent which a resin composition can contain, etc.

For example, a preferable example of the lower limit of the weight average molecular weight is

Moreover, a preferable example of the upper limit of a weight average molecular weight is,

For example, in terms of elongation and yellowness (YI) of a cured product of a resin composition containing a polyimide precursor (for example, a polyimide film (also referred to as a cure film in the present disclosure)), a weight average molecular weight of 120,000 or more This is preferable, 130,000 or more are more preferable, and 160,000 or more are especially preferable. Moreover, from a viewpoint of the haze of the said hardened|cured material (for example, polyimide film), 220,000 or less are preferable and 200,000 or less are more preferable. A preferable aspect WHEREIN: The weight average molecular weights of a polyimide precursor are 160,000 or more and 220,000 or less.

(Retardation in thickness direction (Rth) of polyimide film)

When a polyimide film is produced as a hardened|cured material (namely, imidation product) of a polyimide precursor, thickness direction retardation (Rth) in the film thickness of 10 micrometers of the said polyimide film changes with the monomer skeleton of a polyimide precursor. However, if it is the same monomer skeleton, there exists a tendency for Rth to be small, so that the weight average molecular weight of a polyimide precursor is large. As a polymer skeleton, when DAS is used, there exists a tendency for Rth to become small. Although the mechanism of the said relationship of the weight average molecular weight of a polyimide precursor and Rth of a polyimide film is unclear, it is thought that the orientation of the molecule|numerator of a polyimide film, and crystallinity are related.

A specific aspect WHEREIN: From a viewpoint of obtaining a polyimide film of low birefringence, Rth is 300 nm or less. In particular, when using a polyimide film as a display material, as Rth, 200 nm or less is preferable, 100 nm or less is more preferable, 80 nm or less is more preferable, 50 nm or less is more preferable, 30 nm is especially desirable. When Rth is 300 nm or less, it is easy to accurately capture an image, and in particular, when Rth is 200 nm or less, the color reproducibility of the image is good.

In one aspect, the polyimide film has a thickness direction retardation (Rth) of 300 nm or less in terms of a film thickness of 10 µm, and/or a yellowness (YI) of 20 or less in terms of a film thickness of 10 µm. . One aspect WHEREIN: The thickness direction retardation (Rth) of a polyimide film in conversion of 10 micrometers of film thickness is 300 nm or less, and yellowness (YI) in conversion of a film thickness of 10 micrometers is 20 or less.

(Yellowness (YI) of polyimide film)

A specific aspect WHEREIN: When a polyimide film is produced as hardened|cured material (that is, imidated material) of a polyimide precursor, the yellowness (YI) in the film thickness of 10 micrometers of the said polyimide film is favorable optical characteristic From a viewpoint, it is 20 or less, Preferably it is 18 or less, More preferably, it is 16 or less, More preferably, it is 14 or less, More preferably, it is 13 or less, More preferably, it is 10 or less, Especially preferably, it is 7 or less. Although YI in the film thickness of 10 micrometers of the said polyimide film changes with the monomer skeleton of a polyimide precursor, if it is the same monomer skeleton, it exists in the tendency for YI to be small, so that the weight average molecular weight of a polyimide precursor is large.

(Other desirable properties of polyimide film)

When a polyimide film is produced on an inorganic support substrate such as a glass substrate as a cured product (i.e., imidized product) of a polyimide precursor, the polyimide film has a thickness of 10 µm and is generated between the polyimide film and the glass substrate. Residual stress, for example, from the viewpoint of reducing the amount of curvature of a glass substrate with polyimide on the production side of a display use, Preferably it is 25 MPa or less, More preferably, it is 23 MPa or less, More preferably, it is 20 MPa or less, More preferably, it is 18 MPa or less, Especially preferably, it is 16 MPa or less.

Moreover, it is preferable that the tensile elongation in the film thickness of 10 micrometers of the said polyimide film is 15 % or more. From the viewpoint of the mechanical strength of the flexible display, the tensile elongation is more preferably 20% or more, still more preferably 25% or more, still more preferably 30% or more, still more preferably 35% or more, particularly preferably In most cases, it is 40% or more. Although the tensile elongation of the said polyimide film changes with the monomer skeleton of a polyimide precursor, if it is the same monomer skeleton, there exists a tendency for tensile elongation to be large, so that the weight average molecular weight of a polyimide precursor is large.

The glass transition temperature Tg of the polyimide film is preferably 360 ° C. or higher, more preferably 400 ° C. or higher, and more preferably 470 ° C. The above is more preferable.

It is preferable that the film thickness of a polyimide film is uniform. In particular, when a polyimide film is used as a material for a screen such as a flexible display, the wavelength of visible light is about 380 nm to about 700 nm, so from the viewpoint of obtaining good display performance and from the viewpoint of the manufacturing process of the display, a particularly high film Thickness uniformity is required. The film thickness uniformity of the polyimide film (standard deviation of multiple points of the film thickness) is preferably 10 µm or less, preferably 8 µm or less, preferably 5 µm or less, preferably 3 µm or less, and 2 µm or less. is preferably 1 µm or less, particularly preferably 500 nm or less, particularly preferably 300 nm or less. Although the film thickness uniformity is so preferable that it is small, 50 nm or more or 100 nm or more may be sufficient from a viewpoint of the yield improvement of display manufacture, for example. In addition, the said film thickness uniformity means the value of 3σ calculated from the film thickness of multiple points measured by the method described in the term of [Example] of this indication, for example.

(Shear Rate Dependence of Resin Composition)

The shear rate dependence (TI) (hereinafter, simply referred to as TI) of the resin composition of the present embodiment is preferably 0.9 or more and 1.1 or less. In the present disclosure, TI is the viscosity ηa (mPa·s) at the measurement rotation speed a (rpm) when the viscosity of the resin composition is measured with a viscometer with a temperature controller (TVE-35H manufactured by Toki Sangyo Co., Ltd.) at 23° C. , from the viscosity ηb (mPa·s) (provided that a * 10 = b) at the measurement rotation speed b (rpm), the following formula:

TI = ηa/ηb

It is a value obtained according to Details of the measurement conditions are described in the description in Examples.

The shear rate dependence (TI) is preferably 0.9 or more, or 0.95 or more, or 1.0 or more, and preferably 1.1 or less, or 1.05 or less, or 1.0 or less. When TI is this range, a resin composition is said to be a Newtonian fluid, and since the film-thickness uniformity at the time of slit-coating a resin composition is favorable, it is preferable. Since the polyimide film obtained by hardening|curing the resin composition with favorable film-thickness uniformity has favorable film-thickness uniformity, it can use suitably as a material of screens, such as a flexible display.

Although the detailed reason for which film thickness uniformity becomes favorable when the shear rate dependence of a resin composition is 0.9 or more and 1.1 or less is not clear, it thinks as follows.

In a slit coat, the shear rate provided to the resin composition immediately after the start of application|coating is small, and the shear rate provided to the resin composition when application|coating is continued is large. When the shear rate dependence is small (specifically, TI is 0.9 or more and 1.1 or less), the difference in the viscosity of the resin composition immediately after the start of application and when the application is continued is small, so the film thickness variation in the application direction (MD (Machine direction)) is small (that is, the film thickness uniformity in the application direction is good). In addition, when the slit coat nozzle has a specification for injecting the resin composition from only one end in the transverse direction (TD), the shear rate of the resin composition is large in the vicinity of the injection port during slit coating, but on the opposite side to the injection port (that is, on the deadlock side of a nozzle), the shear rate of a resin composition becomes small. Even in such a case, since the shear rate dependence is small (specifically, TI is 0.9 or more and 1.1 or less), the film thickness dispersion|variation in the width direction can be made small. As described above, the small shear rate dependence (specifically, TI of 0.9 or more and 1.1 or less) reduces the influence on the viscosity due to shear, and the film thickness variation is small in both MD and TD (that is, the film thickness uniformity is good).

It is thought that the shear rate dependence of a resin composition has correlation with the synthesis|combining method of a resin composition.

For example, when all of an acid dianhydride, a diamine, and a silicone oil which may be an acid dianhydride or a diamine depending on the structure are added to the reaction vessel and reacted by heating, and the diamine dissolved in a solvent Comparing the case where acid dianhydride and the silicone oil dissolved in the solvent are added dropwise at room temperature over time and reacted little by little, in the former case, among monomers (ie, acid dianhydride, diamine and silicone oil), It reacts with those with higher reactivity (such as those with higher acidity or basicity, and those with less steric hindrance), and the polyimide precursor tends to become a block polymer. On the other hand, in the latter case, since acid dianhydride and silicone oil are dissolved in a solvent and dripped in small amounts, each monomer can react regardless of reactivity or the like, and the polyimide precursor tends to become a random polymer. As described above, in the former and the latter, it is considered that the polymer composition of the product is different. And in the case of a block polymer (the former), since specific monomers are gathered in the polymer, intermolecular interaction between polymer chains is likely to occur, or polymer flexibility is impaired, so it is thought that stacking between polymer chains becomes easy. As a result, it is thought that the shear rate dependence of a resin composition becomes large. On the other hand, in the latter case, it is considered that the shear rate dependence is small because the respective monomers are sequentially bonded and intermolecular interaction or the like does not easily occur.

Moreover, in the former case, since all monomers are added and heated, it is thought that acid dianhydride group ring-opens with a heat|fever before especially a part of acid dianhydride reacts with a polymer chain. Since reactivity becomes low compared with an acid dianhydride group when an acid dianhydride group is ring-opening and becomes a dicarboxyl group, it is thought that the molecular weight of a polyimide precursor becomes small. On the other hand, in the latter case, in order to melt|dissolve acid dianhydride in a solvent and to drip it little by little at room temperature, it becomes possible to react with a polymer chain without an acid dianhydride group ring-opening, and it is thought that molecular weight becomes large.

(Slit Coat Characteristics of Resin Composition)

The coating characteristic (slit-coat characteristic) by the slit nozzle of the resin composition containing a polyimide precursor correlates with the weight average molecular weight of a polyimide precursor, and solid content content of a resin composition. When the polyimide precursor has a low molecular weight and/or when the resin composition has a low solid content, liquid leakage from the nozzle tends to occur, while when the polyimide precursor has a high molecular weight, and/or the resin composition has a high In the case of solid content, clogging of the varnish is likely to occur at the tip of the nozzle. Therefore, it is preferable to control the weight average molecular weight of a polyimide precursor in the range from which a desired slit-coat characteristic is obtained by controlling solid content.

(Edge characteristics of coating film)

When the resin composition containing the polyimide precursor is slit-coated to form a dry coating film, when the polyimide precursor has a low molecular weight and/or when the resin composition has a low solid content, sagging of the edges tends to occur, while , when the polyimide precursor has a high molecular weight, and/or when the resin composition has a high solid content, edge beads (ie, ridges of the edges) are likely to occur. Therefore, it is preferable to control the weight average molecular weight of a polyimide precursor in the range from which a desired edge characteristic is acquired by controlling solid content content.

One aspect WHEREIN: Solid content content of a resin composition is 10 mass % - 25 mass %. The settable coating gap (that is, the gap between the tip of the slit coat nozzle and the substrate) when slit-coating the resin composition is correlated with the solid content of the resin composition, and if the type of solid content contained in the resin composition is the same, There exists a tendency which can enlarge a coat gap, so that solid content content is small. From the viewpoint of good coating, it is preferable that the coat gap is large, for example, if the coat gap is 50 μm or more, collision of the slit nozzle with the substrate can be avoided even when the substrate size is relatively large. When solid content of a resin composition is 10 mass % - 25 mass %, the kind and molecular weight of a polyimide precursor can be selected and the objective coat gap can be implement|achieved. The preferable solid content of a resin composition may differ according to a desired use, the kind and molecular weight of a polyimide precursor, the kind of solvent which the resin composition can contain, etc.

Preferred examples of the lower limit of the solid content are 11 mass%, 12 mass%, 13 mass%, 14 mass%, 15 mass%, 16 mass%, 17 mass%, 18 mass%, 19 mass%, 20 mass%, 21 mass%, 22 mass%, 23 mass%, or 24 mass%.

Preferred examples of the upper limit of the solid content are 24 mass%, 23 mass%, 22 mass%, 21 mass%, 20 mass%, 19 mass%, 18 mass%, 17 mass%, 16 mass%, 15 mass%, 14 mass%, 13 mass%, 12 mass%, or 11 mass%.

A preferable aspect WHEREIN: Solid content concentration is 10-20 mass %, and 10-15 mass % is more preferable.

In a preferable aspect, a polyimide precursor is Formula (3):

[Formula 8]

{wherein, each of R ₃ and R ₄ , when there is a plurality, each independently represents a monovalent aliphatic hydrocarbon group having 1 to 5 carbon atoms or a monovalent aromatic group having 6 to 10 carbon atoms, and m is 1 to 200 It is an integer of } has a structure represented by .

R ₃ and R ₄ are a monovalent aliphatic hydrocarbon group having 1 to 5 carbon atoms or a monovalent aromatic group having 6 to 10 carbon atoms, from the viewpoint of obtaining a polyimide capable of reducing residual stress and Rth generated between the support and the support. It is advantageous. A methyl group, an ethyl group, a propyl group, a butyl group, a phenyl group etc. are mentioned as a preferable structure of R< ₃ > and R< ₄ >.

m is 1-200, preferably 1 or more, or 3 or more, or 5 or more, from the viewpoint of obtaining a polyimide capable of reducing the residual stress and Rth generated between the support and the support body, preferably, 200 or less, or 180 or less, or 160 or less.

Although a polyimide precursor may have the structure of Formula (3) in any site|part in a molecule|numerator, it is preferable that the structure of Formula (3) is derived from a diamine component from a viewpoint of the kind and cost of a siloxane monomer. From a viewpoint of reducing the residual stress and Rth which generate|occur|produce between a support body, and the ratio of the structural site|part represented by Formula (3) in the polyimide precursor total mass, Preferably it is 5 mass % or more, More preferably, 6 It is mass % or more, More preferably, it is 7 mass % or more, From a viewpoint of transparency and heat resistance of the hardened|cured material (for example, polyimide film) obtained, Preferably it is 40 mass % or less, More preferably, it is 30 mass % or less. , More preferably, it is 25 mass % or less.

A typical aspect WHEREIN: The polyimide precursor of the structure shown by the said Formula (1) is a polymer of the diamine component containing R< ₁ > group, and the acid dianhydride component containing R< ₂ > group.

Examples of the acid dianhydride containing the R ₂ group include pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic Acid dianhydride, 4,4′-(hexafluoroisopropylidene)diphthalic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-cyclohexene-1,2 Dicarboxylic acid anhydride, 1,2,3,4-benzenetetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,2',3,3' -benzophenonetetracarboxylic dianhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride, methylene-4,4'-diphthalic dianhydride, 1,1-ethylidene-4 ,4'-diphthalic dianhydride, 2,2-propylidene-4,4'-diphthalic dianhydride, 1,2-ethylene-4,4'-diphthalic dianhydride, 1,3-trimethylene-4 ,4'-diphthalic dianhydride, 1,4-tetramethylene-4,4'-diphthalic dianhydride, 1,5-pentamethylene-4,4'-diphthalic dianhydride, 4,4'-oxydi Phthalic dianhydride, p-phenylenebis(trimellitate anhydride), thio-4,4'-diphthalic dianhydride, sulfonyl-4,4'-diphthalic dianhydride, 1,3-bis(3, 4-dicarboxyphenyl)benzene dianhydride, 1,3-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 1, 3-bis[2-(3,4-dicarboxyphenyl)-2-propyl]benzene dianhydride, 1,4-bis[2-(3,4-dicarboxyphenyl)-2-propyl]benzene dianhydride, Bis[3-(3,4-dicarboxyphenoxy)phenyl]methane dianhydride, bis[4-(3,4-dicarboxyphenoxy)phenyl]methane dianhydride, 2,2-bis[3-(3 ,4-dicarboxyphenoxy)phenyl]propane dianhydride, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride, bis(3,4-dicarboxyphenoxy)dimethyl silane dianhydride, 1,3-bis(3,4-dicarboxyphenyl)-1,1,3,3-tetramethyldisiloxane dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride; 1,4,5,8-naphthalenetetracarboxylic dianhydride, 1,2,5,6- Naphthalenetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 2,3,6,7-anthracenetetracarboxylic dianhydride, 1,2,7,8-phenane Trentetracarboxylic dianhydride etc. can be illustrated.

Especially, when pyromellitic dianhydride (PMDA) and biphenyl tetracarboxylic dianhydride (BPDA) control solid content of a resin composition within the range of the predetermined weight average molecular weight of a polyimide precursor, favorable It is preferable from a viewpoint of slit coat performance and favorable mechanical properties and optical properties of hardened|cured material (for example, a polyimide film), and a high glass transition temperature being obtained easily. 1 aspect WHEREIN: The polyimide precursor which has a structure represented by Formula (1) is a copolymer of tetracarboxylic dianhydride and diamine. 1 aspect WHEREIN: A polyimide precursor is a copolymer of tetracarboxylic dianhydride containing pyromellitic dianhydride (PMDA), and diamine. Moreover, one aspect WHEREIN: A polyimide precursor is a copolymer of tetracarboxylic dianhydride containing 3,3',4,4'- biphenyltetracarboxylic dianhydride, and diamine.

A specific aspect WHEREIN: The total content of pyromellitic dianhydride (PMDA) and biphenyltetracarboxylic dianhydride (BPDA) in all acid dianhydrides has favorable slit-coat performance, and hardened|cured material (for example, From the viewpoint of obtaining good thickness direction retardation (Rth), yellowness (YI), glass transition temperature Tg, and elongation of the mid film), preferably 60 mol% or more, more preferably 80 mol% or more, particularly preferably It is usually 100 mol%.

A specific aspect WHEREIN: Content of pyromellitic dianhydride (PMDA) in all acid dianhydride is a viewpoint of obtaining favorable slit-coat performance and favorable glass transition temperature Tg of hardened|cured material (for example, polyimide film). , 0 mol% or more is preferable, 10 mol% or more is preferable, 20 mol% or more is preferable, 100 mol% or less is preferable, and 90 mol% or less is preferable.

Specific aspect WHEREIN: Content of biphenyl tetracarboxylic dianhydride (BPDA) in all acid dianhydride is favorable thickness direction retardation of slit-coat performance and hardened|cured material (for example, polyimide film). From the viewpoint of obtaining (Rth), yellowness (YI), and elongation, 0 mol% or more is preferable, 10 mol% or more is preferable, 20 mol% or more is preferable, 100 mol% or less is preferable, and 90 mol% or less is preferable. mol% or less is preferable.

A specific aspect WHEREIN: The content ratio of pyromellitic dianhydride (PMDA):biphenyltetracarboxylic dianhydride (BPDA) in acid dianhydride is favorable thickness direction retardation of hardened|cured material (for example, polyimide film) From a viewpoint of making the heat resistance typified by dation (Rth), yellowness (YI), and glass transition temperature compatible, 20:80-80:20 is preferable and 30:70-70:30 are more preferable. A specific aspect WHEREIN: A polyimide precursor is a copolymer of tetracarboxylic dianhydride and diamine, The tetracarboxylic dianhydride is pyromellitic dianhydride and 3,3',4,4'-biphenyl For tetracarboxylic dianhydride, the molar ratio of pyromellitic dianhydride:3,3',4,4'-biphenyltetracarboxylic dianhydride is 20:80-80:20, More preferably 30:70- 70:30 is included.

Examples of the diamine containing the R ₁ group in the formula (1) include diaminodiphenylsulfone (eg, 4,4′-diaminodiphenylsulfone, 3,3′-diaminodiphenylsulfone), p- Phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylsulfide, 3,4'-diaminodiphenylsulfide, 3,3'-diaminodiphenylsulfide, 4,4' -diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 4,4'-diaminobenzophenone, 3,4'-diaminobenzophenone, 3,3' -diaminobenzophenone, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 1,4-bis(4-aminophenoxy) ) Benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, 4,4- Bis(4-aminophenoxy)biphenyl, 4,4-bis(3-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]ether, bis[4-(3-aminophenoxy)biphenyl Cy)phenyl]ether, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 9,10-bis(4-aminophenyl)anthracene, 2,2-bis (4-aminophenyl)propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl)propane, 2,2-bis[4 -(4-aminophenoxy)phenyl)hexafluoropropane, 1, 4-bis(3-aminopropyl dimethylsilyl)benzene, etc. are mentioned.

The diamine used in order to form the polyimide precursor which has a structure represented by Formula (1) is diaminodiphenylsulfone (For example, 4,4'- diaminodiphenylsulfone and/or 3,3'-dia minodiphenylsulfone).

50 mol% or more is preferable, as for content of the diaminodiphenylsulfone in all diamine, 70 mol% or more is more preferable, 90 mol% or more is still more preferable, 95 mol% or more may be sufficient. It is so preferable from a viewpoint of yellowness (YI) of hardened|cured material (for example, polyimide film), glass transition temperature Tg, and thickness direction retardation Rth, so that there is much quantity of diaminodiphenyl sulfone. As diaminodiphenylsulfone, 4,4'- diaminodiphenylsulfone is especially preferable from a viewpoint of a low yellowness (YI).

In a preferred embodiment, the diamine to be copolymerized with diaminodiphenylsulfone is preferably diamide biphenyls from the viewpoint of heat resistance of the cured product (eg polyimide film) and yellowness (YI). , more preferably diaminobis(trifluoromethyl)biphenyl (TFMB). The content of diaminobis(trifluoromethyl)biphenyl (TFMB) in all the diamines is preferably 20 mol% or more from the viewpoint of the yellowness (YI) of the cured product (eg, polyimide film). It is preferably 30 mol% or more, and is preferably 80 mol% or less, more preferably 70 mol% or less, from the viewpoint of allowing the diamine to contain other advantageous components such as diaminodiphenylsulfone.

A preferable aspect WHEREIN: Diamine contains a silicon-containing diamine. A more preferable aspect WHEREIN: Diamine contains the silicon containing diamine containing the structure represented by Formula (3) mentioned above. As the silicon-containing diamine, for example, the following formula (3a):

[Formula 9]

{wherein, R ₅ represents a divalent hydrocarbon group, may be the same as or different from each other, each of a plurality of R ₃ and R ₄ is the same as defined in the formula (3), and l is an integer of 1 to 200 Diamino (poly) siloxane represented by } can be preferably used.

As a preferable structure of R< ₅ > in the said General formula (3a), a methylene group, an ethylene group, a propylene group, a butylene group, a phenylene group, etc. are mentioned. Moreover, as a preferable structure of R< ₃ > and R< ₄ > in Formula (3a), a methyl group, an ethyl group, a propyl group, a butyl group, a phenyl group, etc. are mentioned.

The number average molecular weight of the compound represented by the formula (3a) is preferably 500 or more, more preferably 500 or more, from the viewpoint of reducing the residual stress generated between the obtained cured product (eg, polyimide film) and the support. 1,000 or more, more preferably 2,000 or more, from the viewpoint of transparency (particularly low HAZE) of the resulting cured product (eg polyimide film), preferably 12,000 or less, more preferably 10,000 or less, still more preferably less than 8,000.

Specific examples of the compound represented by the formula (3a) include both terminal amine-modified methylphenyl silicone oil (manufactured by Shin-Etsu Chemical Co., Ltd.: X22-1660B-3 (number average molecular weight 4400), X22-9409 (number average molecular weight 1300)), Amino-modified dimethyl silicone at both ends (Shin-Etsu Chemical Corporation: X22-161A (number average molecular weight 1600), X22-161B (number average molecular weight 3000), KF8012 (number average molecular weight 4400), Toray Dow Corning manufacture: BY16-835U (number average molecular weight) Molecular weight 900) Chisso Corporation make: Cyraprene FM3311 (number average molecular weight 1000)) etc. are mentioned. Among these, both terminal amine-modified methylphenyl silicone oil is preferable from the viewpoint of improving chemical resistance and Tg.

As for the copolymerization ratio of silicon-containing diamine, the range of 0.5-30 mass % is preferable with respect to the mass of all the polyimide precursors, More preferably, 1.0 mass % - 25 mass %, More preferably, 1.5 mass % - 20 mass % % to be. When it is 0.5 mass % or more, the fall effect of the stress which generate|occur|produces between a support body is favorable. Moreover, when it is 30 mass % or less, transparency (especially low HAZE) of the hardened|cured material obtained (for example, a polyimide film) is favorable, and it is preferable from the point of realization of a high total light transmittance, and fall prevention of Tg.

As an acid component for forming the polyimide precursor in this embodiment, in the range which does not impair the performance, in addition to acid dianhydride (for example, tetracarboxylic dianhydride illustrated above), dicarboxylic acid You may use an acid. That is, a polyamideimide precursor may be sufficient as the polyimide precursor of this indication. The film obtained from such a polyimide precursor may have favorable various performances, such as mechanical elongation, glass transition temperature Tg, and yellowness (YI). As dicarboxylic acid to be used, dicarboxylic acid and alicyclic dicarboxylic acid which have an aromatic ring are mentioned. It is especially preferable that it is at least 1 compound selected from the group which consists of C8-C36 aromatic dicarboxylic acid and C6-C34 alicyclic dicarboxylic acid. The number of carbons contained in a carboxyl group is also included in carbon number here. Among these, the dicarboxylic acid which has an aromatic ring is preferable.

Specifically, for example, isophthalic acid, terephthalic acid, 4,4'-biphenyldicarboxylic acid, 3,4'-biphenyldicarboxylic acid, 3,3'-biphenyldicarboxylic acid, 1, 4-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-sulfonylbisbenzoic acid, 3, 4'-sulfonylbisbenzoic acid, 3,3'-sulfonylbisbenzoic acid, 4,4'-oxybisbenzoic acid, 3,4'-oxybisbenzoic acid, 3,3'-oxybisbenzoic acid, 2,2-bis (4-carboxyphenyl)propane, 2,2-bis(3-carboxyphenyl)propane, 2,2'-dimethyl-4,4'-biphenyldicarboxylic acid, 3,3'-dimethyl-4,4 '-biphenyldicarboxylic acid, 2,2'-dimethyl-3,3'-biphenyldicarboxylic acid, 9,9-bis(4-(4-carboxyphenoxy)phenyl)fluorene, 9, 9-bis(4-(3-carboxyphenoxy)phenyl)fluorene, 4,4'-bis(4-carboxyphenoxy)biphenyl, 4,4'-bis(3-carboxyphenoxy)biphenyl, 3,4'-bis(4-carboxyphenoxy)biphenyl, 3,4'-bis(3-carboxyphenoxy)biphenyl, 3,3'-bis(4-carboxyphenoxy)biphenyl, 3, 3'-bis(3-carboxyphenoxy)biphenyl, 4,4'-bis(4-carboxyphenoxy)-p-terphenyl, 4,4'-bis(4-carboxyphenoxy)-m-ter Phenyl, 3,4'-bis(4-carboxyphenoxy)-p-terphenyl, 3,3'-bis(4-carboxyphenoxy)-p-terphenyl, 3,4'-bis(4-carboxy Phenoxy)-m-terphenyl, 3,3'-bis(4-carboxyphenoxy)-m-terphenyl, 4,4'-bis(3-carboxyphenoxy)-p-terphenyl, 4,4 '-bis(3-carboxyphenoxy)-m-terphenyl, 3,4'-bis(3-carboxyphenoxy)-p-terphenyl, 3,3'-bis(3-carboxyphenoxy)-p -terphenyl, 3,4'-bis(3-carboxyphenoxy)-m-terphenyl, 3,3'-bis(3-carboxyphenoxy)-m-terphenyl, 1,1-cyclobutanedicar Acid, 1,4-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4,4'-benzophenonedicarboxylic acid, 1,3-phenylenediacetic acid, 1,4- phenylene diacetic acid; and 5-aminoisophthalic acid derivatives described in International Publication No. 2005/068535 pamphlet. When actually copolymerizing these dicarboxylic acids with a polymer, you may use in the form of an acid chloride body derived from thionyl chloride etc., an active ester body, etc.

In a preferred aspect, the polyimide precursor is tetracarboxylic dianhydride, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 2,2'-bis(trifluoro It is a copolymer of at least one diamine selected from the group consisting of methyl)benzidine and 9,9-bis(4-aminophenyl)fluorene.

The following are mentioned as a especially preferable polyimide precursor.

(1) a polycondensate of a material component in which the acid dianhydride component is pyromellitic dianhydride (PMDA) and biphenyltetracarboxylic dianhydride (BPDA), and the diamine component is diaminodiphenylsulfone (DAS) (more preferably silver has a weight average molecular weight of 110,000 to 130,000, and a solid content of 12 to 25 mass%)

(2) Polycondensate of a material component in which the acid dianhydride component is pyromellitic dianhydride (PMDA) and biphenyltetracarboxylic dianhydride (BPDA), and the diamine component is diaminodiphenylsulfone (DAS) and silicon-containing diamine (More preferably, a weight average molecular weight of 110,000-210,000, solid content 10-25 mass %)

(3) The acid dianhydride component is pyromellitic dianhydride (PMDA) and biphenyltetracarboxylic dianhydride (BPDA), and the diamine component is diaminodiphenylsulfone (DAS), diaminobis(trifluoromethyl) Polycondensate of a material component that is biphenyl (TFMB) and silicon-containing diamine (more preferably, a weight average molecular weight of 110,000 to 250,000, a solid content of 10 to 25 mass%)

(4) a polycondensate of a material component in which the acid dianhydride component is pyromellitic dianhydride (PMDA) and the diamine component is diaminodiphenylsulfone (DAS) (more preferably, a weight average molecular weight of 110,000 to 140,000, a solid content of 10 ~ 25% by mass)

(5) a polycondensate of a material component in which the acid dianhydride component is pyromellitic dianhydride (PMDA), the diamine component is diaminodiphenylsulfone (DAS) and silicon-containing diamine (more preferably, a weight average molecular weight of 110,000 to 230,000) , solid content 10 to 25 mass%)

(6) material component in which the acid dianhydride component is pyromellitic dianhydride (PMDA), the diamine component is diaminodiphenylsulfone (DAS), diaminobis(trifluoromethyl)biphenyl (TFMB) and silicon-containing diamine of polycondensate (more preferably, a weight average molecular weight of 110,000 to 250,000, and a solid content of 10 to 25 mass%)

(7) a polycondensate of a material component in which the acid dianhydride component is biphenyltetracarboxylic dianhydride (BPDA) and the diamine component is diaminodiphenylsulfone (DAS) (more preferably, a weight average molecular weight of 110,000 to 120,000; Solid content 20-25 mass %)

(8) a polycondensate of a material component in which the acid dianhydride component is biphenyltetracarboxylic dianhydride (BPDA), the diamine component is diaminodiphenylsulfone (DAS) and silicon-containing diamine (more preferably, a weight average molecular weight) 110,000 to 160,000, solid content 10 to 25 mass%)

(9) The acid dianhydride component is biphenyltetracarboxylic dianhydride (BPDA), the diamine component is diaminodiphenylsulfone (DAS), diaminobis(trifluoromethyl)biphenyl (TFMB), and silicon-containing diamine Polycondensate of phosphorus material component (more preferably, weight average molecular weight 110,000-240,000, solid content 10-25 mass %)

In the material component of the polycondensate of the above (1) to (9), the silicon-containing diamine is preferably diamino(poly)siloxane represented by the above formula (3a) (preferably having a number average molecular weight of 500 to 12,000) ), and more preferably both terminal amine-modified methylphenyl silicone oil.

[Preparation of polyimide precursor]

The polyimide precursor of this embodiment is compoundable by making the polycondensation component containing an acid dianhydride component and a diamine component polycondensate. A preferable aspect WHEREIN: A polycondensation component consists of an acid dianhydride component and a diamine component. It is preferable to carry out a polycondensation reaction in a suitable solvent. Specifically, for example, after dissolving a predetermined amount of the diamine component in a solvent, a predetermined amount of acid dianhydride is added to the obtained diamine solution, and the method of stirring is mentioned.

The molar ratio of the acid dianhydride component and the diamine component at the time of synthesize|combining a polyimide precursor is acid dianhydride:diamine=100:90-100: from a viewpoint of high molecular weight-ization of polyimide precursor resin, and the slit coating characteristic of a resin composition: 110 (0.90 to 1.10 mole parts of diamine with respect to 1 mole part of acid dianhydride), and more preferably 100:95 to 100:105 (0.95 to 1.05 mole parts of diamine with respect to 1 mole part of acid dianhydride) desirable.

The molecular weight of a polyimide precursor can be controlled by the kind of an acid dianhydride component and a diamine component, adjustment of ratio of an acid dianhydride component and a diamine component, addition of a terminal blocker, adjustment of reaction conditions, etc. A polyimide precursor can be made high molecular weight, so that ratio of an acid dianhydride component and a diamine component is close to 1:1, and there is little usage-amount of a terminal blocker. It is recommended to use high-purity products as the acid dianhydride component and the diamine component. The purity is preferably 98 mass% or more, more preferably 99 mass% or more, and still more preferably 99.5 mass% or more. Moreover, it can also be highly purified by reducing the water content in an acid dianhydride component and a diamine component. When using multiple types of acid dianhydride components or diamine components together, it is enough to have said purity as the whole of an acid dianhydride component or a diamine component, However, All types of acid dianhydride components and diamine components to be used are each It is preferable to have the above purity.

As a solvent of reaction, an acid dianhydride component, a diamine component, and the polyimide precursor which generate|occur|produced can be melt|dissolved, and if it is a solvent from which a high molecular weight polymer is obtained, a restriction|limiting in particular will not be carried out. Specific examples of such a solvent include, for example, an aprotic solvent, a phenolic solvent, an ether, and a glycol-based solvent. Specific examples thereof include, for example, N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP) as the aprotic solvent. ), N-methylcaprolactam, 1,3-dimethylimidazolidinone, tetramethylurea, the following general formula (4):

[Formula 10]

amide solvents such as Ecamide M100 (trade name: manufactured by Idemitsu Kogsan Co., Ltd.) represented by R ₁₂ = methyl group, and Ecamide B100 (trade name: Idemitsu Kogsan Co., Ltd.) represented by R ₁₂ = n-butyl group; lactone solvents such as γ-butyrolactone and γ-valerolactone; phosphorus-containing amide solvents such as hexamethylphosphoricamide and hexamethylphosphine triamide; sulfur-containing solvents such as dimethyl sulfone, dimethyl sulfoxide and sulfolane; ketone solvents such as cyclohexanone and methylcyclohexanone; tertiary amine solvents such as picoline and pyridine; Ester solvents such as acetic acid (2-methoxy-1-methylethyl), etc.: Examples of the phenolic solvent include phenol, o-cresol, m-cresol, p-cresol, and 2,3-xylenol. , 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, etc.: as the ether and glycol solvents For example, 1,2-dimethoxyethane, bis(2-methoxyethyl)ether, 1,2-bis(2-methoxyethoxy)ethane, bis[2-(2-methoxyethoxy)ethyl ] Ether, tetrahydrofuran, 1,4-dioxane, etc. are mentioned, respectively. You may use these solvents individually or in mixture of 2 or more types.

60-300 degreeC is preferable, as for the boiling point in normal pressure of the solvent used for the synthesis|combination of a polyimide precursor, 140-280 degreeC is more preferable, 170-270 degreeC is especially preferable. When the boiling point of a solvent is higher than 300 degreeC, a drying process becomes necessary for a long time. On the other hand, when the boiling point of the solvent is lower than 60°C, roughness occurs on the surface of the resin film, mixing of air bubbles into the resin film, etc. occur during the drying step, and a uniform film may not be obtained. In particular, it is preferable to use a solvent having a boiling point of 170 to 270°C and/or a solvent having a vapor pressure of 250 Pa or less at 20°C from the viewpoints of solubility and edge repelling during coating. More specifically, at least one selected from the group consisting of N-methyl-2-pyrrolidone (NMP), γ-butyrolactone (GBL), and a compound represented by the general formula (4) is preferable.

It is preferable that the water content in a solvent is 3,000 mass ppm or less from a viewpoint of advancing favorable polycondensation reaction, for example. Moreover, in the resin composition in this embodiment, it is preferable that content of the molecule|numerator of molecular weight less than 1,000 is less than 5 mass %. It is thought that the presence of a molecule|numerator of molecular weight less than 1,000 in a resin composition is because the water content of the solvent used at the time of synthesis|combination, and raw material (acid dianhydride, diamine) is involved. That is, the acid anhydride group of some acid dianhydride monomers hydrolyzes with water|moisture content, becomes a carboxyl group, and it is thought based on what remains in a low molecular state, without making it high molecular weight. Therefore, it is so preferable that the water content of the solvent used for the said polycondensation reaction is small. It is preferable to set it as 3,000 mass ppm or less, and, as for the moisture content of a solvent, it is more preferable to set it as 1,000 mass ppm or less. Similarly, it is preferable to set it as 3,000 mass ppm or less also about the moisture content contained in a raw material, and it is more preferable to set it as 1,000 mass ppm or less.

The water content of the solvent depends on the grade of the solvent used (dehydration grade, general-purpose grade, etc.), solvent container (bottle, 18 L can, canister can, etc.), storage condition of the solvent (whether or not sealed with noble gas, etc.), from opening to use. Time (whether to use immediately after opening, whether to use after time has elapsed after opening, etc.) is considered to be involved. Moreover, it is thought that the rare gas substitution of the reactor before synthesis|combination, the presence or absence of the rare gas flow|circulation during synthesis|combination, etc. are also involved. Therefore, when synthesizing the polyimide precursor, it is recommended to use a high-purity product as a raw material, use a solvent with a low water content, and take measures to prevent moisture from the environment from entering the system before and during the reaction.

When dissolving each polycondensation component in a solvent, you may heat as needed. From a viewpoint that a polyimide precursor with a high degree of polymerization is obtained, as a preferable reaction temperature at the time of polyimide precursor synthesis, 0 degreeC - 120 degreeC, or 40 degreeC - 100 degreeC, or 60-100 degreeC can be illustrated, Preferred polymerization As time, 1 to 100 hours or 2 to 10 hours can be illustrated. By making polymerization time into 1 hour or more, it becomes a polyimide precursor of a uniform polymerization degree, and by setting it as 100 hours or less, a polyimide precursor with a high polymerization degree can be obtained.

The resin composition of this embodiment may be a combination of a polyimide precursor having a structure represented by Formula (1) and another additional polyimide precursor, but the mass ratio of the additional polyimide precursor is From the viewpoint of reducing the oxygen dependence of the yellowness (YI) and total light transmittance of the mid film), it is preferably 30 mass % or less, and more preferably 10 mass % or less with respect to the total amount of the polyimide precursor in the resin composition.

A preferable aspect of this embodiment WHEREIN: As for the polyimide precursor, the part may be imidated. According to the partially imidated polyimide precursor, the viscosity stability at the time of room temperature storage of a resin composition can be improved. The imidation ratio in this case is preferably 5% or more, more preferably 8% or more, and preferably 80% from the viewpoint of balancing the solubility of the polyimide precursor in the resin composition and storage stability of the solution. Below, more preferably, it is 70 % or less, More preferably, it is 50 % or less. This partial imidation is obtained by heating a polyimide precursor and dehydrating and ring-closing. This heating becomes like this. Preferably it is a temperature of 120-200 degreeC, More preferably, it is 150-180 degreeC. WHEREIN: Preferably it is 15 minutes - 20 hours, More preferably, it can perform 30 minutes - 10 hours. In addition, N,N-dimethylformamide dimethyl acetal or N,N-dimethylformamide diethyl acetal is added to the polyamic acid obtained by the reaction described above and heated to esterify part or all of the carboxylic acid. After carrying out, the resin composition in which the viscosity stability at the time of room temperature storage improved can also be obtained by using as a polyimide precursor in this embodiment. In addition, these ester-modified polyamic acids react sequentially with the above-mentioned acid dianhydride component with 1 equivalent of monohydric alcohol with respect to the acid anhydride group, and a dehydration-condensing agent such as thionyl chloride and dicyclohexylcarbodiimide. After making it, it can obtain also by the method of making a diamine component and a condensation reaction.

In one aspect, the resin composition includes a solvent. As a solvent, it is preferable that the solubility of a polyimide precursor is favorable and can control the solution viscosity of a resin composition suitably, and the reaction solvent of the said polyimide precursor can be used as a solvent of a composition. Among them, N-methyl-2-pyrrolidone (NMP), γ-butyrolactone (GBL), a compound represented by the general formula (4), and the like are preferable. As a specific example of the solvent composition, N-methyl-2-pyrrolidone (NMP) alone or a mixed solvent of N-methyl-2-pyrrolidone (NMP) and γ-butyrolactone (GBL) (eg, For example, NMP:GBL (mass ratio)=10:90-90:10) etc. are mentioned.

[additional ingredients]

The resin composition of this embodiment may contain the further component in addition to (a) a polyimide precursor and (b) a solvent. As an additional component, (c) surfactant, (d) an alkoxysilane compound, etc. are mentioned.

((c) surfactant)

By adding surfactant to the resin composition of this embodiment, the applicability|paintability of the resin composition can be improved. Specifically, generation|occurrence|production of the stripe in a coating film can be prevented.

Examples of such surfactants include silicone-based surfactants, fluorine-based surfactants, and nonionic surfactants other than these surfactants. Examples of these include, as silicone surfactants, organosiloxane polymers KF-640, 642, 643, KP341, X-70-092, X-70-093 (above, trade name, manufactured by Shin-Etsu Chemical Industries, Ltd.), SH -28PA, SH-190, SH-193, SZ-6032, SF-8428, DC-57, DC-190 (above, trade names, manufactured by Toray Dow Corning Silicon Corporation), SILWET L-77, L-7001, FZ-2105, FZ-2120, FZ-2154, FZ-2164, FZ-2166, L-7604 (above, trade name, manufactured by Nippon Unica), DBE-814, DBE-224, DBE-621, CMS-626, CMS-222, KF-352A, KF-354L, KF-355A, KF-6020, DBE-821, DBE-712 (Gelest), BYK-307, BYK-310, BYK-378, BYK-333 (or above, brand name) , Big Chemie Japan), Granol (trade name, Kyoeisha Chemical Co., Ltd. make) etc.; As a fluorochemical surfactant, Megapac F171, F173, R-08 (made by Dainippon Ink Chemical Industries, Ltd., brand name), Florad FC4430, FC4432 (Sumitomo 3M Corporation, brand name) etc. are, for example; As nonionic surfactants other than these, polyoxyethylene uraryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octyl phenol ether, etc. are mentioned, respectively, for example.

Among these surfactants, silicone-based surfactants and fluorine-based surfactants are preferable from the viewpoint of coatability (streak suppression) of the resin composition. From the viewpoint, silicone-based surfactants are preferred. (c) When using surfactant, 0.001-5 mass parts is preferable with respect to 100 mass parts of (a) polyimide precursors in a resin composition, and, as for the compounding quantity, 0.01-3 mass parts is more preferable.

(d) alkoxysilane compounds

When using the polyimide film obtained from the resin composition which concerns on this embodiment for a flexible board|substrate etc., from a viewpoint of obtaining favorable adhesiveness of the support body in a manufacturing process, and a polyimide film, the resin composition is (a) polyimide precursor 100 0.01-20 mass parts of alkoxysilane compounds can be contained with respect to mass part. When content of the alkoxysilane compound with respect to 100 mass parts of polyimide precursors is 0.01 mass part or more, favorable adhesiveness between a support body and a polyimide film can be acquired. Moreover, it is preferable from a viewpoint of storage stability of a resin composition that content of an alkoxysilane compound is 20 mass parts or less. It is more preferable that content of an alkoxysilane compound is 0.02-15 mass parts with respect to 100 mass parts of polyimide precursors, It is still more preferable that it is 0.05-10 mass parts, It is especially preferable that it is 0.1-8 mass parts.

Moreover, by using an alkoxysilane compound as an additive of the resin composition which concerns on this embodiment, in addition to said adhesive improvement, the improvement of coatability (streak nonuniformity suppression) of a resin composition, and yellowness (YI) of the cured film obtained It is also possible to reduce the dependence of the oxygen concentration upon curing the value.

Examples of the alkoxysilane compound include 3-ureidopropyltriethoxysilane, bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, γ -Aminopropyltrimethoxysilane, γ-aminopropyltripropoxysilane, γ-aminopropyltributoxysilane, γ-aminoethyltriethoxysilane, γ-aminoethyltripropoxysilane, γ-aminoethyltribu Toxysilane, γ-aminobutyltriethoxysilane, γ-aminobutyltrimethoxysilane, γ-aminobutyltripropoxysilane, γ-aminobutyltributoxysilane, phenylsilane triol, trimethoxyphenylsilane, Trimethoxy(p-tolyl)silane, diphenylsilanediol, dimethoxydiphenylsilane, diethoxydiphenylsilane, dimethoxydi-p-tolylsilane, triphenylsilanol and an alkoxysilane compound represented by each of the following structures etc. are mentioned, It is preferable to use 1 or more types chosen from these.

[Formula 11]

The manufacturing method of the resin composition in this embodiment is not specifically limited, For example, it can depend on the following method.

(a) When the solvent used when synthesize|combining a polyimide precursor and the solvent contained in (b) resin composition are the same, the synthesize|combined polyimide precursor solution can be used as a resin composition as it is. Moreover, as needed, in the temperature range of room temperature (25 degreeC) - 80 degreeC, after adding and stirring and mixing 1 or more types of (b) a solvent and an additional component to (a) polyimide precursor, the resin composition may be used as For this stirring and mixing, an appropriate device such as a three-one motor provided with stirring blades (manufactured by Shinto Chemical Co., Ltd.) and an autorotation revolving mixer can be used. Moreover, you may apply the heat|fever of 40-100 degreeC as needed.

On the other hand, when the solvent used when synthesize|combining (a) polyimide precursor and the solvent contained in (b) resin composition differ, the solvent in the synthesize|combined polyimide precursor solution is reprecipitated, solvent distillation, etc., for example. (a) after isolating the polyimide precursor by removing by an appropriate method of may be prepared.

After preparing the resin composition as mentioned above, a part of polyimide precursor is dehydrated imide by heating the composition at 130-200 degreeC for 5 minutes - 2 hours, for example, to such an extent that a polymer does not raise|generate precipitation. can be reconciled Here, the imidation rate can be controlled by controlling the heating temperature and the heating time. As described above, according to the partially imidized polyimide precursor, the viscosity stability of the resin composition during storage at room temperature can be improved.

From the viewpoint of slit coat performance, the solution viscosity of the resin composition is preferably 500 to 100,000 mPa·s, more preferably 1,000 to 50,000 mPa·s, and particularly preferably 3,000 to 20,000 mPa·s. Specifically, it is preferably 500 mPa·s or more, more preferably 1,000 mPa·s or more, and still more preferably 3,000 mPa·s or more from the viewpoint of being difficult to leak from the slit nozzle. Moreover, since the slit nozzle is hard to be clogged, Preferably it is 100,000 mPa*s or less, More preferably, it is 50,000 mPa*s or less, More preferably, it is 20,000 mPa*s or less. Moreover, from a viewpoint of the viscosity at the time of synthesis, when the solution viscosity of a resin composition is higher than 200,000 mPa*s, there exists a possibility that the problem that stirring at the time of synthesis becomes difficult may arise. However, when synthesizing, even if the solution becomes highly viscous, it is possible to obtain a resin composition having good handleability by adding and stirring a solvent after completion of the reaction. The solution viscosity of the resin composition in this indication is a value measured at 23 degreeC using the E-type viscometer (For example, VISCONICEHD, the Toki Sangyo make).

It is preferable that the moisture content of the resin composition which concerns on this embodiment is 3,000 mass ppm or less. The moisture content of the resin composition is preferably 2,500 mass ppm or less, preferably 2,000 mass ppm or less, preferably 1,500 mass ppm or less, and 1,000 mass ppm or less from the viewpoint of viscosity stability when the resin composition is stored. It is preferable, and it is more preferable that it is 500 mass ppm or less, 300 mass ppm or less is preferable, and 100 mass ppm or less is preferable.

<The manufacturing method of a polyimide film>

This embodiment is

A coating step of applying the resin composition of the present embodiment on the surface of the support;

A film forming step of heating the resin composition to form a polyimide film;

A method for producing a polyimide film comprising a peeling step of peeling the polyimide film from a support is provided.

[Applying process]

A coating process WHEREIN: A resin composition is apply|coated on the surface of a support body. A support body will not be specifically limited, if it has heat resistance in the heating temperature of a subsequent film formation process (heating process) and the peelability in a peeling process is favorable. For example, a glass (for example, alkali free glass) board|substrate; silicon wafer; PET (polyethylene terephthalate), OPP (stretched polypropylene), polyethylene glycol terephthalate, polyethylene glycol naphthalate, polycarbonate, polyimide, polyamideimide, polyetherimide, polyetheretherketone, polyethersulfone, polyphenylene resin substrates such as sulfone and polyphenylene sulfide; Metal substrates, such as stainless steel, alumina, copper, nickel, etc. are used.

When forming a thin-film polyimide molded body, for example, a glass substrate, a silicon wafer, etc. are preferable, and when forming a thick-film-shaped polyimide molded body (for example, a thick film, a sheet, etc.), for example, , PET (polyethylene terephthalate), OPP (stretched polypropylene), etc. are preferable.

As a coating method, Generally, Coating methods, such as a doctor blade knife coater, an air knife coater, a roll coater, a rotary coater, a flow coater, a die coater, a bar coater, A coating method, such as spin coating, spray coating, and dip coating; Although the printing technique etc. typified by screen printing, gravure printing, etc. are mentioned, The resin composition of this embodiment is especially useful for slit coating (that is, application|coating to a slit coater). Although application|coating thickness should be suitably adjusted according to the thickness of a desired polyimide film, and content of the polyimide precursor in a resin composition, Preferably it is about 1-1,000 micrometers. Although implementation in room temperature is sufficient for an application|coating process, you may heat and implement a resin composition in the range of 40-80 degreeC for the purpose of lowering a viscosity and improving workability|operativity.

[Optional drying process]

Continuing to the application step, a drying step may be performed, or the drying step may be omitted and the process may proceed directly to the next film formation step (heating step). The said drying process is implemented for the objective of the organic solvent removal in a resin composition. When performing a drying process, suitable apparatuses, such as a hot plate, a box-type dryer, and a conveyor-type dryer, can be used, for example. It is preferable to implement at 80-200 degreeC, and, as for a drying process, it is more preferable to implement at 100-150 degreeC. It is preferable to set it as 1 minute - 10 hours, and, as for the implementation time of a drying process, it is more preferable to set it as 3 minutes - 1 hour. As mentioned above, the coating film containing a polyimide precursor is formed on a support body.

[Film forming process]

Then, the film formation process (heating process) is implemented. A heating process is a process of advancing the imidation reaction of the polyimide precursor in a coating film, and obtaining a polyimide film while removing the organic solvent which remained in the coating film at the said drying process. This heating process can be implemented using apparatuses, such as an inert gas oven, a hot plate, a box-type dryer, and a conveyor-type dryer, for example. This process may be performed simultaneously with the said drying process, and you may implement both processes sequentially.

Although the heating process may be performed in an air atmosphere, it is recommended to carry out in an inert gas atmosphere from a viewpoint of obtaining safety, favorable transparency of the polyimide film obtained, low thickness direction retardation (Rth), and low yellowness (YI). do. As an inert gas, nitrogen, argon, etc. are mentioned, for example. Although heating temperature may be set suitably according to the kind of a polyimide precursor, and the kind of solvent in a resin composition, 250 degreeC - 550 degreeC are preferable, and 300-450 degreeC is more preferable. If it is 250 degreeC or more, imidation advances favorably, and if it is 550 degrees C or less, problems, such as a fall of transparency of the polyimide film obtained, and deterioration of heat resistance, can be avoided. The heating time is preferably about 0.1 to 10 hours.

In this embodiment, 2,000 mass ppm or less is preferable from a viewpoint of transparency of the polyimide film obtained, and yellowness (YI) value, and, as for the oxygen concentration of the ambient atmosphere in said heating process, 100 mass ppm or less is more It is preferable, and 10 mass ppm or less is more preferable. When an oxygen concentration heats in an atmosphere of 2,000 mass ppm or less, the yellowness (YI) value of the polyimide film obtained can be 30 or less.

[Peeling process]

Next, at a peeling process, after cooling the polyimide film on a support body to about room temperature - about 50 degreeC, it peels. As this peeling process, the aspect of following (1)-(4) is mentioned, for example.

(1) After producing a structure including a polyimide film/support by the above method, a laser is irradiated from the support side of the structure, and the interface between the support and the polyimide film is ablated to produce a polyimide resin How to peel. As a kind of laser, a solid-state (YAG) laser, a gas (UV excimer) laser, etc. are mentioned. It is preferable to use a spectrum with a wavelength of 308 nm or the like (refer to Japanese Patent Application Laid-Open No. 2007-512568, Japanese Patent Application Laid-Open No. 2012-511173, etc.).

(2) Before coating a resin composition on a support body, a peeling layer is formed in a support body, After that, the structural body containing a polyimide film / peeling layer / support body is obtained, and the method of peeling a polyimide film. As the release layer, parylene (registered trademark, manufactured by Nippon Parylene Co., Ltd.) and tungsten oxide are used; and a method using a release agent such as vegetable oil, silicone, fluorine, or alkyd (see Japanese Patent Application Laid-Open No. 2010-67957, Japanese Patent Application Laid-Open No. 2013-179306, etc.).

You may use this method (2) and the laser irradiation of said (1) together.

(3) A method of obtaining a polyimide film by using an etchable metal substrate as a support to obtain a structure including a polyimide film/support, and then etching the metal with an etchant. As a metal, copper (As a specific example, the electrolytic copper foil "DFF" manufactured by Mitsui Metals Mining Co., Ltd.), aluminum, etc. can be used, for example. As the etchant, ferric chloride or the like for copper and dilute hydrochloric acid or the like can be used for aluminum.

(4) By the above method, after obtaining a structure including a polyimide film/support body, the adhesive film is affixed to the surface of the polyimide film, the adhesive film/polyimide film is separated from the support body, and then the polyimide film is separated from the adhesive film How to separate the mid film.

Among these peeling methods, method (1) or (2) is suitable from the viewpoint of the refractive index difference of the front and back of the polyimide film obtained, the yellowness (YI) value, and the elongation. From the viewpoint of the method (1), that is, prior to the peeling step, it is more appropriate to perform an irradiation step of irradiating a laser from the support side.

Moreover, in the method (3), when copper is used as a support body, the yellowness (YI) value of the polyimide film obtained becomes large, and the tendency for elongation to become small is seen. This is considered to be the influence of copper ions.

Although the thickness of the polyimide film obtained by said method is not specifically limited, It is preferable that it is the range of 1-200 micrometers, More preferably, it is 5-100 micrometers.

<Use of polyimide film>

The polyimide film obtained from the polyimide precursor which concerns on this embodiment is applicable as a semiconductor insulating film, a TFT-LCD insulating film, an electrode protective film, etc., for example, and manufacture of a flexible device WHEREIN: In particular, a TFT substrate and a color It can use suitably as a filter board|substrate and a touchscreen board|substrate. Here, as a flexible device to which the polyimide film which concerns on this embodiment is applicable, For example, TFT device for flexible displays, a flexible solar cell, a flexible touch panel, a flexible illumination, a flexible battery, a flexible printed circuit board, a flexible color filter, A surface cover lens for exclusive use of a smartphone, etc. are mentioned.

The process of forming TFT on the flexible substrate using a polyimide film is typically performed at the temperature of the wide range of 150-650 degreeC. In the case of producing a TFT device using amorphous silicon specifically, in general, a process temperature of 250°C to 350°C is required, and since the polyimide film of the present embodiment needs to be able to withstand the temperature, specifically As such, it is necessary to appropriately select a polymer structure having a glass transition temperature equal to or higher than the process temperature and a thermal decomposition initiation temperature.

In the case of manufacturing a TFT device using a metal oxide semiconductor (IGZO or the like), a process temperature of generally 320°C to 400°C is required, and the polyimide film of the present embodiment needs to be able to withstand the temperature, It is necessary to appropriately select a polymer structure having a glass transition temperature and thermal decomposition initiation temperature equal to or higher than the TFT fabrication process maximum temperature.

In the case of producing a TFT device using low-temperature polysilicon (LTPS), a process temperature of 380°C to 520°C is generally required, and the polyimide film of the present embodiment needs to be able to withstand the temperature. It is necessary to appropriately select the glass transition temperature and thermal decomposition start temperature equal to or higher than the production process maximum temperature.

On the other hand, due to these thermal histories, the optical properties (especially light transmittance, retardation properties, and yellowness) of the polyimide film tend to deteriorate as they are exposed to a high-temperature process. However, the polyimide obtained from the polyimide precursor of this embodiment has favorable optical characteristics even if it passes through a thermal history.

Below, as a use example of the resin composition of this embodiment, and a polyimide film, a display, a laminated body, and these manufacturing methods are demonstrated.

[Display and its manufacturing method]

This embodiment also provides the flexible device containing the polyimide film which is hardened|cured material of the resin composition of this embodiment. A suitable example of the flexible device is a flexible display. In one aspect, the polyimide film is excellent in optical properties (eg, Rth and/or yellowness). Therefore, in a preferable aspect, a polyimide film is arrange|positioned at the point (specifically, the screen part of a flexible display) visually recognized when a display is observed from the outside.

This embodiment is

A coating step of applying (preferably slit coating) the resin composition of the present embodiment on the surface of a support such as a glass substrate;

A film forming step of heating the resin composition to form a polyimide film;

an element forming step of forming an element on a polyimide film;

Also provided is a method for manufacturing a display including a peeling step of peeling a polyimide film having an element formed thereon from a support.

[Method for manufacturing flexible organic EL display]

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure above the polyimide board|substrate of a top emission type flexible organic electroluminescent display as an example of the display provided by one aspect|mode of this invention. When the organic EL structure part 25 of FIG. 1 is described, for example, an organic EL element 250a that emits red light, an organic EL element 250b that emits green light, and an organic EL element 250c that emits blue light are As one unit, they are arranged in a matrix form, and the light emitting region of each organic EL element is defined by a partition (bank) 251 . Each organic EL element is constituted by a lower electrode (anode) 252 , a hole transport layer 253 , a light emitting layer 254 , and an upper electrode (cathode) 255 . Moreover, on the lower layer 2a which shows the CVD multilayer film (multi-barrier layer) which consists of silicon nitride (SiN) or silicon oxide (SiO), TFT 256 (low temperature polysilicon (LTPS)) for driving an organic electroluminescent element, a metal A plurality of oxide semiconductors (such as IGZO), an interlayer insulating film 258 having a contact hole 257, and a lower electrode 259 are formed. The organic EL element is sealed with a sealing substrate 2b, and a hollow portion 261 is formed between each organic EL element and the sealing substrate 2b.

In the flexible organic EL display manufacturing process, a polyimide film is produced on a glass substrate support, and the organic EL substrate shown in FIG. 1 is manufactured thereon, a sealing substrate manufacturing process, an assembly process of bonding both substrates, and , a peeling step of peeling the organic EL display produced on the polyimide film from the glass substrate support is included.

A well-known manufacturing process is applicable to an organic electroluminescent board|substrate manufacturing process, a sealing board|substrate manufacturing process, and an assembly process. Although the example is given below, it is not limited to this. Moreover, the peeling process may be the same as the peeling process of the polyimide film mentioned above.

Referring to FIG. 1 , for example, first, a polyimide film of the present disclosure is produced on a glass substrate support by the method described above, and silicon nitride (SiN) and silicon oxide are formed thereon by a CVD method or a sputtering method. A multi-barrier layer (lower substrate 2a in FIG. 1 ) having a multilayer structure of (SiO) is prepared, and a metal wiring layer for driving the TFT is formed thereon using a photoresist or the like. An active buffer layer, such as SiO, is produced on the upper part using the CVD method, and TFT devices (TFT 256 in FIG. 1), such as a metal oxide semiconductor (IGZO) and low-temperature polysilicon (LTPS), are produced in the upper part. After the TFT substrate for flexible display is produced, an interlayer insulating film 258 having contact holes 257 is formed with a photosensitive acrylic resin or the like. An ITO film is formed by a sputtering method or the like, and the lower electrode 259 is formed so as to form a pair with the TFT.

Next, after forming the barrier ribs (banks) 251 with photosensitive polyimide or the like, the hole transporting layer 253 and the light emitting layer 254 are formed in each space partitioned by the barrier ribs. Moreover, the upper electrode (cathode) 255 is formed so that the light emitting layer 254 and the partition (bank) 251 may be covered. Then, using a fine metal mask or the like as a mask, an organic EL material emitting red light (corresponding to the organic EL element 250a emitting red light in FIG. 1) and an organic EL material emitting green light (in FIG. 1, An organic EL substrate by depositing an organic EL element 250b that emits green light) and an organic EL material that emits blue light (corresponding to the organic EL element 250c that emits blue light in Fig. 1) by a known method. This is produced, and after sealing with a sealing film or the like (sealing substrate 2b in Fig. 1), the device above the polyimide substrate from the glass substrate support is peeled off by a known peeling method such as laser peeling, so that the flexible top emission type An organic EL display is fabricated. When the polyimide of this embodiment is used, a see-through type flexible organic EL display is produced. Moreover, you may produce the flexible organic electroluminescent display of a bottom emission type by a well-known method.

[Method for manufacturing flexible liquid crystal display]

A flexible liquid crystal display can be produced using the polyimide film of this embodiment. As a specific manufacturing method, the polyimide film which consists of this invention on a glass substrate support body is produced by the above-mentioned method, and using the above-mentioned method, for example, amorphous silicon, a metal oxide semiconductor (IGZO, etc.), Alternatively, a TFT substrate made of low-temperature polysilicon is manufactured. Separately, according to the application process and the film formation process of this embodiment, a polyimide film is produced on a glass substrate support body, and a color resist etc. are used according to a well-known method, The color filter glass substrate provided with the polyimide film. (CF substrate) is produced. On one of the TFT substrate and the CF substrate, a sealing material composed of a thermosetting epoxy resin or the like is applied by screen printing in a frame-like pattern lacking the liquid crystal injection port, and on the other substrate, equivalent to the thickness of the liquid crystal layer. A spherical spacer made of plastic or silica is dispersed.

Next, the TFT substrate and the CF substrate are bonded, and the sealing material is cured.

Finally, a liquid crystal layer is formed by injecting a liquid crystal material into the space surrounded by the TFT substrate, the CF substrate, and the sealing material by a reduced pressure method, then applying a thermosetting resin to the liquid crystal injection port and sealing the liquid crystal material by heating. do. Finally, a flexible liquid crystal display can be produced by peeling the glass substrate by the side of CF and the glass substrate by the side of TFT at the interface of a polyimide film and a glass substrate by a laser peeling method etc.

[Method for producing a laminate]

This embodiment is

A coating step of applying the resin composition of the present embodiment on the surface of the support;

A film forming step of heating the resin composition to form a polyimide film;

Also provided is a method for manufacturing a laminate including an element forming step of forming an element on a polyimide film.

As an element in a laminated body, what was illustrated as said flexible device (for example, a flexible display) is mentioned. A glass substrate is used as a support body, for example. Preferred specific procedures of the application step and the film formation step are the same as those described above with respect to the method for producing the polyimide film described above. Moreover, in an element formation process, said element is formed on the polyimide film as a flexible substrate formed on the support body. Then, in a peeling process, you may peel a polyimide film and an element from a support body arbitrarily.

Example

Hereinafter, the present invention will be described in more detail based on examples, but these are described for the purpose of explanation, and the scope of the present invention is not limited to the following examples. Various evaluations in Examples and Comparative Examples were performed as follows.

<Weight Average Molecular Weight>

The weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured by gel permeation chromatography (GPC) under the following conditions.

As the solvent, NMP (manufactured by Wako Pure Chemical Industries, Ltd., for high performance liquid chromatography, 24.8 mmol/L lithium bromide monohydrate (manufactured by Wako Pure Chemical Industries, Ltd., purity 99.5%) immediately before measurement) and 63.2 mmol/L phosphoric acid (manufactured by Wako Pure Chemical Industries, Ltd.) , for high performance liquid chromatograph) was added and dissolved) was used. The calibration curve for calculating the weight average molecular weight was produced using standard polystyrene (made by Tosoh Corporation).

Column: Shodex KD-806M (manufactured by Showa Denko)

Flow rate: 1.0 ml/min

Column temperature: 40℃

Pump: PU-2080Plus (manufactured by JASCO)

Detector: RI-2031Plus (RI: Differential Refractometer, manufactured by JASCO) and UV-2075Plus (UV-VIS: Ultraviolet-Visible Absorber, manufactured by JASCO)

<Evaluation of shear rate dependence (TI)>

The viscosity of the resin composition prepared in Examples and Comparative Examples was measured at 23°C using a viscometer with a temperature controller (TVE-35H manufactured by Toki Industries Co., Ltd.), the rotational speed and cone rotor at which the viscosity of the resin composition to be measured can be measured. was used, and shear rate dependence evaluation was performed.

Specifically, the viscosity ηa (mPa·s) at the measurement rotation speed a (rpm) and the viscosity ηb (mPa·s) at the measurement rotation speed b (rpm) are measured (here, a * 10 = b ), TI represented by the following formula was obtained.

TI = ηa/ηb

Specific examples of the measurable rotational speed are, for example, 0.5, 1, 2.5, 5, 10, 20, 50, 100 rpm.

Specific examples of a measurable cone rotor are, for example, 1°34′ (angle of cone rotor) × R24 (diameter of cone rotor), 1°34′ × R12, 0.8° × R24, 0.8° × R12, 3 ° × R24, 3° × R12, 3° × R17.65, 3° × R14, 3° × R12, 3° × R9.7.

<Coating evaluation>

The resin composition prepared in Examples and Comparative Examples was applied to a glass substrate of 300 mm * 300 mm with a coating area of 295 mm * 295 mm using a slit coater (manufactured by SCREEN Finetech Solutions Co., Ltd.), and coating evaluation was carried out.

(Slit nozzle evaluation)

The resin composition (varnish) prepared in the Example and the comparative example was filled in the nozzle of a slit coater, the following reference|standard evaluated, and it described in the table|surface.

After the discharge of the varnish from the nozzle is started and the discharge is stopped, the varnish flows out from the slit nozzle: liquid leakage

Varnish does not eject from the nozzle: clogging

Coating without leakage or clogging: no problem

(coat gap)

The film thickness of the resin composition (varnish) prepared in Examples and Comparative Examples after imidization (in an oxygen concentration of 10 mass ppm or less, heating at 100°C for 1 hour, and then heating at 400°C for 30 minutes) is 10 µm Coating was carried out on a glass substrate as much as possible (application rate of 100 mm/sec). The coat gap setting values of the slit coater at that time were described in the table.

(Edge evaluation)

The resin composition prepared in Examples and Comparative Examples was coated on a glass substrate, moved to a drying furnace and heated at 100° C. for 1 hour, and then the edge portion of the coating film was observed at 10 times using an optical microscope, and evaluated according to the following criteria. .

Moreover, the edge bead (raise|lifting of an edge part) of the coating film was measured using the stylus type step meter (P-15: manufactured by KLA Tencor), and the following criteria evaluated.

On microscopic observation of the edge portion, liquid dripping with a width of 0.5 mm or more is observed: sagging.

In the film thickness measurement of the edge portion, the bead thickness is 30% or more of the applied film thickness: bead

No deflection, no edge anomalies: no problem

(Slit coat or not)

About the said (slit nozzle evaluation), (coat gap), and (edge evaluation), the following reference|standard evaluated and described in the table|surface.

In the composition using the polyimide precursor having a predetermined weight average molecular weight of each Example and Comparative Example, at least any solid content in the range of 7 to 28 mass%, all of the following evaluation results are satisfied:

The composition using the polyimide precursor of the predetermined polymerization average molecular weight of each Example and the comparative example WHEREIN: In the range of 7-28 mass % of solid content, all the following evaluation results are not satisfied: No

Slit nozzle evaluation: no problem

Coat gap: 50 μm or more

Edge Rating: No Problem

<Cured film thickness uniformity (standard deviation)>

The polyimide film according to the Example and Comparative Example produced on a glass substrate in the above <coating evaluation> (coat gap) (that is, a polyimide film formed at a size of 295 mm * 295 mm on a 300 mm * 300 mm glass substrate) ) was used. Using a glass substrate provided with a polyimide film, from the center of the coated surface toward each end face of MD (that is, slit coat direction) and TD (direction perpendicular to MD), the film thickness at a position at an interval of 20 mm was measured (therefore, the tip is at a position of 7.5 mm from the cross section) (30 points in total by 15 MD points and 15 TD points). For the measurement of the film thickness, a contact-type step meter was used. From the result, the film thickness uniformity (standard deviation of the film thickness of 30 points|pieces) of a polyimide film was calculated, and the following reference|standard evaluated.

Amount: In-plane film thickness uniformity (3 sigma) 1.0 μm or less

A: In-plane film thickness uniformity (3 sigma) exceeds 1.0 μm and less than or equal to 2.0 μm

Poor: In-plane film thickness uniformity (3 sigma) exceeds 2.0 μm

<Cured film elongation>

The resin compositions prepared in Examples and Comparative Examples were spin-coated on a 6-inch silicon wafer substrate having an aluminum vapor deposition layer formed on the surface thereof to a film thickness of 10 µm after curing, and prebaked at 100°C for 6 minutes. Then, using a vertical curing furnace (manufactured by Koyo Lindbergh, model name: VF-2000B), the oxygen concentration in the furnace is adjusted to be 10 mass ppm or less, and heat curing treatment is performed at 400°C for 30 minutes. Thus, a wafer having a polyimide film formed thereon was produced. Next, using a dicing saw (DAD 3350 manufactured by Disco Co., Ltd.), a 3 mm-wide incision was made in the polyimide film of the wafer, and then immersed in a diluted aqueous hydrochloric acid solution overnight, the film piece was peeled off and dried. This was cut to 50 mm in length, and it was set as the sample.

About the above sample, the elongation was measured using TENSILON (UTM-II-20 manufactured by Orientec Corporation) at a test speed of 40 mm/min and an initial load of 0.5 fs. It was evaluated based on the following criteria, and it is described in the table|surface.

Right: 40% or more

Amount: 20% or more, less than 40%

A: less than 20%

<Cured film haze (Haze)>

In the said <coating evaluation> (coat gap), the polyimide film which concerns on the Example and the comparative example produced on the glass substrate was used.

About the obtained sample, the haze (10 micrometers of film thickness conversion) was measured based on JISK7105 transparency test method using the SC-3H type|mold haze meter manufactured by Suga Test Instruments. The measurement results were evaluated according to the following criteria, and are described in the table.

Right: Haze is 0.5 or less

Amount: Haze greater than 0.5 and less than 1.5

A: Haze is greater than 1.5

<Cured film yellowness (YI))>

In the said <coating evaluation> (coat gap), the polyimide film which concerns on the Example and the comparative example produced on the glass substrate was used. About the obtained sample, the yellowness (YI) value (10 micrometers of film thickness conversion) was measured by the Nippon Denshoku Industries Co., Ltd. product (spectrophotometer: SE600) using the D65 light source. The results are shown in the table.

<Cured film Rth (retardation, retardation in thickness direction)>

In the said <coating evaluation> (coat gap), the polyimide film which concerns on the Example and the comparative example produced on the glass substrate was used. With respect to the obtained sample, Rth (in terms of film thickness of 10 µm) was measured using a phase difference birefringence measuring apparatus (manufactured by Oji Instruments Co., Ltd., KOBRA-WR). The wavelength of the measurement light was 589 nm. The results are shown in the table.

<Comparative Example 1-1>

In a 3 L separable flask with a stirring bar, NMP (812 g) was added while introducing nitrogen gas, and 4,4'-DAS (4,4'-diaminodiphenylsulfone) (14.2 g) as diamine (14.2 g), TFMB (12.2 g), both terminal amine-modified methylphenyl silicone oil (10.56 g) was added with stirring, and then PMDA (15.3 g) and BPDA (8.8 g) were added as acid dianhydride (molar ratio of acid dianhydride and diamine) (100:98)). Next, after heating up to 80 degreeC using the oil bath and stirring for 4 hours, the oil bath was removed and it returned to room temperature, and the NMP solution of a transparent polyamic acid (it is also described hereafter as a varnish) was obtained. The obtained varnish was stored in a freezer (setting -20°C, the same hereinafter), and used after thawing for evaluation.

<Comparative Examples 1-2 to 1-6>

It carried out similarly to Comparative Example 1-1 except that the amount of NMP was changed and it was set as the solid content of Table 1.

<Example 1-1>

In a 3 L separable flask equipped with a stir bar, while introducing nitrogen gas, 4,4'-DAS (15.3 g) and TFMB (12.4 g) as diamines, and a polymerization solvent twice the mass of the total mass of these diamines ( NMP) was added.

Next, a dropping funnel is set in the separable flask, and while nitrogen gas is introduced into the dropping funnel, PMDA (15.3 g) and BPDA (8.8 g) as acid dianhydrides, and polymerization of twice the mass of these acid dianhydrides Solvent (NMP) was added. Then, the mixture was stirred at room temperature with a small stirring blade.

Then, another dropping funnel was set in the separable flask, and nitrogen gas was introduced into the dropping funnel, both terminal amine-modified methylphenyl silicone oil X-22-1660B-3 (10.56 g) as diamine and 2 of the silicone oil. Double the mass of polymerization solvent (NMP) was added. Then, the mixture was stirred at room temperature with a small stirring blade.

And while stirring the diamine solution in a separable flask, at room temperature, dripping of the acid dianhydride solution and silicone oil was started simultaneously, stirring the small stirring blade of the said dropping funnel. All dripping was performed at low speed, and it was dripped over 30 minutes or more. After dripping, it wash|cleaned with the washing|cleaning solvent (NMP), and the residue was dripped (molar ratio of acid dianhydride and diamine (100:99)).

Thereafter, an additional solvent (NMP) was added to finally reach the solid content in Table 1. Subsequently, the mixture was stirred at room temperature for 30 minutes, and then the temperature was raised to 70°C using an oil bath, followed by stirring for 4 hours. Then, the oil bath was removed and it returned to room temperature, and the NMP solution of the transparent polyamic acid (it is also described hereafter as a varnish) was obtained. The obtained varnish was stored in a freezer (setting -20°C, the same hereinafter), and used after thawing for evaluation.

<Examples 1-2 to 1-17, 2-1 to 2-14, 3-1 to 3-16, 4-1 to 4-12>

The mixing of the acid dianhydride and the diamine is as shown in Tables 1 to 4, and the amount of the polymerization solvent used is changed accordingly (that is, adjusted so as to be twice the mass of the acid dianhydride or diamine), and further carried out For Examples 1-5 to 1-8, 2-5 to 2-14, 3-3 to 3-16, and 4-5 to 4-12, “heat up to 70° C. and stir for 4 hours” and “heat up to 40° C.” and stirred for 12 hours", and for Examples 1-9, 2-9, 3-9, and 4-9, "Additional solvent (NMP)" was replaced with "Additional solvent (NMP and GBL) (NMP/GBL after addition") Adjusted so that it may become this 100/100 (w/w))", it carried out similarly to Example 1-1. The solid content shown in Tables 1-4 was adjusted to the value shown in a table|surface by changing the quantity of the said additional solvent. In addition, in Examples 1-16, 2-12, 2-13, 3-14, 3-15, 4-10, 4-11, the weight average molecular weight of those obtained by further extending the reaction time after "stirring for 12 hours" As a result of measuring, there was no case of increasing compared to after stirring for 12 hours.

<Comparative Examples 2-1 to 2-6, 3-1 to 3-6, 4-1 to 4-7>

In Comparative Examples 2-1, 3-1, and 4-1, the amount of NMP in Comparative Example 1-1 was 745 g (Comparative Example 2-1), 799 g (Comparative Example 3-1), 850 g (Comparative Example 4) It changed to -1), respectively, and it implemented similarly to Comparative Example 1-1 except having carried out the compounding of an acid dianhydride and diamine as Table 2 showed. Moreover, except having changed the amount of NMP and having set it as the solid content of Tables 2-4, Comparative Examples 2-2 to 2-6 are Comparative Example 2-1 and Comparative Examples 3-2 to 3-6 Comparative Example 3 -1 and Comparative Examples 4-2 to 4-7 were implemented similarly to Comparative Example 4-1, respectively.

<Comparative Example 5-1>

To a 3 L separable flask with a stirring bar, NMP (620 g) was added while introducing nitrogen gas, 4,4'-DAS (24.8 g) was added as diamine while stirring, and PMDA ( 21.8 g) (molar ratio of acid dianhydride to diamine (100: 100)). Next, after heating up to 80 degreeC using the oil bath and stirring for 4 hours, the oil bath was removed and it returned to room temperature, and the NMP solution of a transparent polyamic acid (it is also described hereafter as a varnish) was obtained. The obtained varnish was stored in a freezer and used after thawing for evaluation.

<Comparative Examples 5-2 to 5-6>

The same procedure as in Comparative Example 5-1 was carried out, except that the amount of NMP was changed and the solid content in Table 5 was set.

<Example 5-1>

4,4'-DAS (24.3 g) and NMP of twice the mass of the total mass of diamine were added to the 3 L separable flask with a stirring bar as diamine, introduce|transducing nitrogen gas.

Next, a dropping funnel is set in the separable flask, and nitrogen gas is introduced into the dropping funnel, PMDA (10.9 g), BPDA (14.7 g) as acid dianhydride, and NMP twice the mass of these acid dianhydrides added. Then, the mixture was stirred at room temperature with a small stirring blade.

And dripping of the acid dianhydride solution was started at room temperature, stirring the diamine solution in a separable flask, stirring the small stirring blade of the said dropping funnel. The dripping was performed at low speed, and it was dripped over 30 minutes or more. After dripping, it wash|cleaned with the washing|cleaning solvent (NMP), and the residue was dripped (molar ratio of acid dianhydride and diamine (100:98)).

After that, an additional solvent (NMP) was added to finally reach the solid content in Table 5. Subsequently, the mixture was stirred at room temperature for 30 minutes, and then the temperature was raised to 70°C using an oil bath, followed by stirring for 4 hours. Then, the oil bath was removed and it returned to room temperature, and the NMP solution of the transparent polyamic acid (it is also described hereafter as a varnish) was obtained. The obtained varnish was stored in a freezer (setting -20°C, the same hereinafter), and used after thawing for evaluation.

<Examples 5-2 to 5-9, 6-1 to 6-9, 7-1 to 7-4, 8-1, 8-2>

The compounding of acid dianhydride and diamine is as shown in Tables 5 to 9, and the amount of polymerization solvent used is changed accordingly (that is, adjusted so as to be twice the mass of acid dianhydride or diamine), and further carried out For Examples 5-3 to 5-9, 6-5 to 6-9, 7-4, 8-1, and 8-2, the above “heat up to 70° C. and stir for 4 hours” is “heated to 40° C. for 12 hours” stirring", and for Examples 5-7, 6-4, 7-4, "additional solvent (NMP)" was replaced with "additional solvent (NMP and GBL) (NMP/GBL after addition was 100/100 (w/ It was carried out similarly to Example 5-1 except having changed to "adjust so that it may become w)". The solid content shown in Tables 5-9 was adjusted to the value shown in a table|surface by changing the quantity of the said additional solvent. Further, in Examples 5-8, 5-9, 6-6 to 6-9, after "stirring for 12 hours", the weight average molecular weight of what was further extended for reaction time was measured, compared with that after stirring for 12 hours. There was no case of enlargement.

<Comparative Examples 6-1 to 6-6, 7-1 to 7-8, 8-1 to 8-2>

In Comparative Examples 6-1, 7-1, 8-1 to 8-2, the amount of NMP in Comparative Example 5-1 was 664 g (Comparative Example 6-1), 718 g (Comparative Example 7-1), 401 g (Comparative Example 8-1) and 344 g (Comparative Example 8-2) were changed respectively to the same as in Comparative Example 5-1, except that the mixing of acid dianhydride and diamine was shown in Tables 6 to 8. carried out. Comparative Examples 6-2 to 6-6 were carried out in the same manner as in Comparative Example 6-1 except that the amount of NMP was changed to be the solid content in Table 6, and Comparative Examples 7-2 to 7-6 were changed to the amount of NMP. It was carried out in the same manner as in Comparative Example 7-1, except that the solid content in Table 7 was used. In Comparative Examples 7-7 and 7-8, the amount of NMP was changed from 718 g to 215 g (Comparative Example 7-7) and 163 g (Comparative Example 7-8), respectively, and the formulation of acid dianhydride and diamine was shown in the table. It carried out as shown in 7, and it carried out similarly to Comparative Example 7-1 except having changed "stirring for 4 hours" to "stirring for 3 hours".

<Comparative Example 9-1>

To a 3 L separable flask with a stirring bar, NMP (495 g) was added while introducing nitrogen gas, and TFMB (30.9 g) was added as a diamine while stirring, followed by BPAF (9,9-bis) as acid dianhydride. (3,4-dicarboxyphenyl)fluorene dianhydride) (45.8 g), X-22-1660B-3 (10.56 g) was added to both terminal amine-modified methylphenyl silicone oil (acid dianhydride, diamine molar ratio ( 100:99)). Next, after heating up to 80 degreeC using the oil bath and stirring for 4 hours, the oil bath was removed and it returned to room temperature, and the NMP solution of a transparent polyamic acid (it is also described hereafter as a varnish) was obtained. The obtained varnish was stored in a freezer and used after thawing for evaluation.

<Comparative Examples 9-2 to 9-3>

The amount of NMP was changed from 495 g to 438 g (Comparative Example 9-2) and 374 g (Comparative Example 9-3), respectively, and the compounding of acid dianhydride and diamine was as shown in Table 9. It carried out similarly to Example 9-1.

<Example 9-1>

TFMB (31.3 g) and NMP (63 g) of twice the mass of the total mass of diamine were added to the 3 L separable flask with a stirring bar as diamine, introduce|transducing nitrogen gas.

Next, a dropping funnel was set in the separable flask, and while nitrogen gas was introduced into the dropping funnel, BPAF (45.8 g) as acid dianhydride and NMP (92 g) twice the mass of this acid dianhydride were added. . Then, the mixture was stirred at room temperature with a small stirring blade.

Then, another dropping funnel was set in the separable flask, and while nitrogen gas was introduced into the dropping funnel, amine-modified methylphenyl silicone oil X-22-1660B-3 (10.56 g) at both ends and twice the amount of the silicone oil. A mass of NMP (21 g) was added. Then, the mixture was stirred at room temperature with a small stirring blade.

And dripping of the acid dianhydride solution was started at room temperature, stirring the diamine solution in a separable flask, stirring the small stirring blade of the said dropping funnel. The dripping was performed at low speed, and it was dripped over 30 minutes or more. It wash|cleaned with the washing|cleaning solvent (NMP) after dripping, and the residue was dripped (molar ratio of acid dianhydride and diamine (100:100)).

Thereafter, an additional solvent (NMP) was added to finally reach the solid content in Table 9.

Then, it stirred at room temperature for 30 minutes, it heated up at 40 degreeC using the oil bath then, and stirred for 12 hours. Then, the oil bath was removed and it returned to room temperature, and the NMP solution of the transparent polyamic acid (it is also described hereafter as a varnish) was obtained. The obtained varnish was stored in a freezer (setting -20°C, the same hereinafter), and used after thawing for evaluation.

<Examples 9-2, 9-3>

Example 9-1 except that the mixing of the acid dianhydride and the diamine was as shown in Table 9, and the amount of the polymerization solvent was changed accordingly (that is, adjusted so as to be twice the mass of the acid dianhydride or diamine). It was carried out in the same way as The solid content shown in Table 9 was adjusted to the value shown in Table by changing the quantity of the said addition solvent.

<Example 10-1>

NMP (246 g) was added to a 3 L separable flask with a stirring bar, introducing nitrogen gas, 4,4'-DAS (14.4 g), TFMB (12.4 g), both terminal amine-modified methylphenyl silicone oil as diamines (10.56 g) was added with stirring, and then PMDA (15.3 g) and BPDA (8.8 g) were added as acid dianhydride (molar ratio of acid dianhydride and diamine (100:99)). Next, after heating up to 70 degreeC using the oil bath and stirring for 8 hours, the oil bath was removed and it returned to room temperature, and the NMP solution of the transparent polyamic acid was obtained. The obtained varnish was stored in a freezer (setting -20°C, the same hereinafter), and used after thawing for evaluation.

<Examples 10-2 to 10-5>

The amount of NMP was changed from 246 g to 225 g (Example 10-2), 242 g (Example 10-3), 185 g (Example 10-4), 201 g (Example 10-5), respectively, It implemented similarly to Example 10-1 except having carried out the mixing|blending of acid dianhydride and diamine as shown in Table 10.

Table 10 shows the results of evaluation.

The resin composition of this indication can be preferably applied to uses, such as a flexible device (for example, a flexible board|substrate), especially a flexible display. For example, the resin composition of this indication can be used suitably in order to form transparent substrates of display apparatuses, such as a liquid crystal display, an organic electroluminescent display, a field emission display, and electronic paper. More specifically, the resin composition of the present disclosure can be used to form a substrate of a thin film transistor (TFT), a substrate of a color filter, a substrate of a transparent conductive film (ITO, IndiumTinOxide), and the like.

2a: lower substrate
2b: encapsulation substrate
25: organic EL structure part
250a: organic EL device emitting red light
250b: organic EL device emitting green light
250c: organic EL element emitting blue light
251 bulkhead (bank)
252: lower electrode (anode)
253: hole transport layer
254: light emitting layer
255: upper electrode (cathode)
256: TFT
257: contact hole
258: interlayer insulating film
259: lower electrode
261: hollow

Claims (23)

Equation (1):

{wherein, when there are a plurality of R ₁ , each independently represents a divalent organic group, R ₂ each independently represents a tetravalent organic group when there is a plurality, and n is a positive integer.} A resin composition comprising a mid precursor and a solvent,
The said polyimide precursor is following formula (3):

{wherein, each of R ₃ and R ₄ , when there is a plurality, each independently represents a monovalent aliphatic hydrocarbon group having 1 to 5 carbon atoms or a monovalent aromatic group having 6 to 10 carbon atoms, and m is 1 to 200 It has a structure represented by },
The polyimide precursor has a weight average molecular weight of 110,000 to 250,000,
The resin composition whose solid content of the said resin composition is 10-25 mass %. The method of claim 1,
The resin composition in which the said polyimide precursor is a copolymer of tetracarboxylic dianhydride containing pyromellitic dianhydride, and diamine. The method of claim 1,
The resin composition in which the said polyimide precursor is a copolymer of tetracarboxylic dianhydride containing 3,3',4,4'- biphenyltetracarboxylic dianhydride, and diamine. 4. The method according to any one of claims 1 to 3,
The resin composition whose shear rate dependence (TI) represented by the following formula when the viscosity of the said resin composition is measured at 23 degreeC with the viscometer with a temperature controller is 0.9-1.1.
TI = ηa/ηb
{wherein, ηa (mPa·s) is the viscosity at the measured rotational speed a (rpm) of the resin composition, and ηb (mPa·s) is the viscosity at the measured rotational speed b (rpm) of the resin composition, However, a * 10 = b.} 4. The method according to any one of claims 1 to 3,
The said resin composition is a resin composition for slit coats, The resin composition. 4. The method according to any one of claims 1 to 3,
At least one of R ₁ in the formula (1) is the following formula (2):

A group represented by , a resin composition. The method of claim 1,
The polyimide precursor is tetracarboxylic dianhydride, 3,3'-diaminodiphenylsulfone, 2,2'-bis(trifluoromethyl)benzidine and 9,9-bis(4-aminophenyl) A resin composition which is a copolymer of at least one diamine selected from the group consisting of fluorene. 4. The method according to any one of claims 1 to 3,
The weight average molecular weight of the said polyimide precursor is 160,000-220,000, the resin composition. 4. The method according to any one of claims 1 to 3,
The said resin composition is a resin composition for flexible devices. 4. The method according to any one of claims 1 to 3,
The said resin composition is a resin composition for flexible displays, The resin composition. The polyimide film which is a hardened|cured material of the resin composition in any one of Claims 1-3. 12. The method of claim 11,
The polyimide film whose thickness direction retardation (Rth) in conversion of a film thickness of 10 micrometers is 300 or less, and/or yellowness (YI) in conversion of a film thickness of 10 micrometers is 20 or less. A flexible device comprising the polyimide film according to claim 11 . A flexible display comprising the polyimide film according to claim 11 . 15. The method of claim 14,
The said polyimide film is arrange|positioned at the point visually recognized when the said flexible display is observed from the outside, The flexible display. A coating step of applying the resin composition according to any one of claims 1 to 3 on the surface of the support;
A film forming step of heating the resin composition to form a polyimide film;
The manufacturing method of the polyimide film including the peeling process of peeling the said polyimide film from the said support body. 17. The method of claim 16,
The said application process is a manufacturing method of a polyimide film including slit-coating the said resin composition. 17. The method of claim 16,
At least one of R ₁ in the formula (1) is the following formula (2):

A group represented by , a method for producing a polyimide film. 17. The method of claim 16,
The said polyimide precursor is following formula (3):

{wherein, each of R ₃ and R ₄ , when there is a plurality, each independently represents a monovalent aliphatic hydrocarbon group having 1 to 5 carbon atoms or a monovalent aromatic group having 6 to 10 carbon atoms, and m is 1 to 200 It is an integer of.} The manufacturing method of the polyimide film which has a structure shown by. 17. The method of claim 16,
The manufacturing method of the polyimide film which further includes the irradiation process of irradiating a laser to the said polyimide film from the said support body before the said peeling process. A coating step of applying the resin composition according to any one of claims 1 to 3 on the surface of the support;
A film forming step of heating the resin composition to form a polyimide film;
an element forming step of forming an element on the polyimide film;
and a peeling step of peeling the polyimide film on which the element is formed from the support. 22. The method of claim 21,
The said application process is a manufacturing method of a display including slit-coating the said resin composition. 22. The method of claim 21,
The manufacturing method of the display which arrange|positions the said polyimide film at the point visually recognized when the said display is observed from the outside.

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