KR20170118138A - Polyimide film, and organic electroluminescent device and organic electroluminescent display using the same - Google Patents

Abstract

[식(1) 중, R¹, R², R³은, 각각 독립적으로 수소 원자 등을 나타내고, R¹⁰은 특정한 기를 나타내고, n은 0 내지 12의 정수를 나타냄]으로 표시되는 반복 단위를 함유하는 폴리이미드를 포함하며, 또한 파장 590nm에서 측정되는 두께 방향의 리타데이션(Rth)이, 두께 10㎛로 환산하여, -100 내지 100nm인, 폴리이미드 필름.(1): < EMI ID =

[Wherein R ¹ , R ² and R ³ each independently represent a hydrogen atom or the like, R ¹⁰ represents a specific group, and n represents an integer of 0 to 12] And a retardation (Rth) in a thickness direction measured at a wavelength of 590 nm is -100 to 100 nm in terms of a thickness of 10 占 퐉.

Description

Polyimide film, and organic electroluminescent device and organic electroluminescent display using the same

The present invention relates to a polyimide film, and an organic electroluminescent device and an organic electroluminescent display using the same.

In recent years, in the field of displays using organic electroluminescent devices and display devices such as liquid crystal displays, etc., it has been required to have light transmittance as well as glass, sufficiently high heat resistance, and appearance of a light and flexible material. As a material for use in such glass substitute applications, a film including a polyimide having a high heat resistance and being light and flexible has been developed.

As such a polyimide, for example, an aromatic polyimide (e.g., " Capton " manufactured by DuPont) is known. However, although such aromatic polyimides are polyimides having sufficient flexibility and high heat resistance, they are not brown and can not be used for glass substitute applications or optical applications which require light transmittance.

For this reason, in recent years, the development of alicyclic polyimide having sufficient light transmittance has been progressing for use in glass substitute applications, and in International Publication No. 2011/099518 (Patent Document 1), for example, A polyimide having a repeating unit represented by a general formula is disclosed. The polyimide as described in Patent Document 1 has sufficient light transmittance and high heat resistance. However, in Patent Document 1, the value of the retardation (retardation) in the thickness direction in the case of forming a film is not particularly described. In the field of display devices, it is desired to use a film or the like having a sufficiently small value of the retardation (Rth) in the thickness direction on a substrate or the like from the viewpoint of improving the contrast and the viewing angle.

International Publication No. 2011/099518

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and it is an object of the present invention to provide a polyimide film which has sufficiently high heat resistance and transparency and can make the absolute value of the retardation (Rth) And an object of the present invention is to provide an organic electroluminescent device using the same.

DISCLOSURE OF THE INVENTION The present inventors have conducted intensive studies in order to achieve the above object, and as a result, they have found that a polyimide film containing a polyimide containing a repeating unit represented by the following general formula (1) has a sufficiently high heat resistance and transparency (Rth) in the thickness direction can be made sufficiently small, and the retardation (Rth) in the thickness direction measured at a wavelength of 590 nm is in the range of -100 to 100 nm (The absolute value is 100 nm or less) can be obtained. Thus, the present invention has been accomplished.

That is, the polyimide of the present invention has the following general formula (1):

Wherein R ¹ , R ² and R ³ each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms and a fluorine atom, and R ¹⁰ is a group represented by the following general formula ( 101) to (108):

And n represents an integer of 0 to 12,

And a polyimide containing a repeating unit represented by the following formula

The retardation (Rth) in the thickness direction measured at a wavelength of 590 nm is -100 to 100 nm in terms of a thickness of 10 mu m.

The polyimide film of the present invention preferably has a retardation (Rth) in the thickness direction measured at the wavelength of 590 nm of -50 to 50 nm.

The organic electroluminescent device of the present invention comprises the polyimide film of the present invention.

The organic electroluminescence display of the present invention comprises the polyimide film of the present invention.

According to the present invention, it is possible to provide a polyimide film which has a sufficiently high heat resistance and transparency, can make the absolute value of the retardation (Rth) in the thickness direction sufficiently small, and an organic electroluminescent device using the same .

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic vertical sectional view showing a preferred embodiment of the organic electroluminescent device of the present invention. Fig.
Fig. 2 is a graph showing the IR spectrum of the polyimide film obtained in Example 1. Fig.

Hereinafter, the present invention will be described in detail based on its preferred embodiments.

[Polyimide film]

The polyimide film of the present invention is represented by the following general formula (1):

Wherein R ¹ , R ² and R ³ each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms and a fluorine atom, and R ¹⁰ is a group represented by the following general formula ( 101) to (108):

And n represents an integer of 0 to 12,

And a polyimide containing a repeating unit represented by the following formula

The retardation (Rth) in the thickness direction measured at a wavelength of 590 nm is -100 to 100 nm in terms of a thickness of 10 mu m.

The alkyl group which may be selected as R ¹ , R ² and R ³ in the general formula (1) is an alkyl group having 1 to 10 carbon atoms. When the number of carbon atoms exceeds 10, the glass transition temperature is lowered and sufficiently high heat resistance can not be achieved. The number of carbon atoms of the alkyl group which can be selected as R ¹ , R ² and R ³ is preferably 1 to 6, more preferably 1 to 5, and most preferably 1 to 4, from the viewpoint of easier purification. , More preferably from 1 to 3 carbon atoms. The alkyl group which may be selected as R ¹ , R ² , and R ³ may be linear or branched. As the alkyl group, a methyl group and an ethyl group are more preferable from the viewpoint of ease of purification.

As R ¹ , R ² and R ³ in the general formula (1), it is preferable that each of R ¹ , R ² and R ³ independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, from the viewpoint of obtaining a higher heat resistance when the polyimide is produced More preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group or an isopropyl group, and more preferably a hydrogen atom or a methyl group, from the viewpoints of easy availability of raw materials and easier purification, Particularly preferred. It is particularly preferable that a plurality of R ¹ , R ² , and R ³ in this formula are the same in terms of ease of purification and the like.

The group that can be selected as R ¹⁰ in the general formula (1) is at least one of the groups represented by the general formulas (101) to (108). When R ¹⁰ in the general formula (1) is a group represented by the general formulas (101) to (108), the retardation (Rth) in the thickness direction measured at a wavelength of 590 nm is -100 to It is possible to obtain a polyimide film having a thickness of 100 nm (the absolute value is 100 nm or less).

Among these R ^{10 s} , from the viewpoint that the absolute value of Rth can be made very small, the groups represented by the general formulas (101), (102) and (103) (105), (106), and (107) are preferable from the viewpoint that it is possible to reduce the absolute value of Rth, , The groups represented by the general formulas (104) and (105)) are preferable. Comparing the formula (101) with the formula (107), R ^{10 is different} from the formula (107) in that the formula (101) has a binding site derived from a diamine at the meta- However, in the group having a structure in which the bonding site derived from diamine is present at the meta position, it is possible to make the absolute value of Rth smaller. Therefore, as compared with the case where the bonding site derived from diamine is present at the para position, It becomes possible to form a film in which the absolute value of the retardation in the direction shows a smaller value. From this viewpoint, it is preferable that R ¹⁰ is a group represented by the above general formulas (101), (102) and (103).

In the general formula (1), n represents an integer of 0 to 12. If the value of n exceeds the upper limit, purification becomes difficult. The upper limit value of the numerical range of n in the general formula (1) is more preferably 5, and particularly preferably 3 from the viewpoint of facilitating purification. The lower limit value of the numerical range of n in the general formula (1) is preferably from the viewpoint of the stability of the starting compound used in forming the repeating unit represented by the general formula (1), that is, , It is more preferable to be 1, and it is particularly preferable to be 2. Thus, n in the general formula (1) is particularly preferably an integer of 2 to 3.

Such a polyimide contains a repeating unit represented by the above-mentioned general formula (1), but it preferably contains a repeating unit represented by the above general formula (1). The polyimide preferably contains 50 mol% or more, more preferably 90 to 100 mol%, and further preferably 100 mol% of the repeating unit represented by the above general formula (1) Particularly preferred. When the content of the repeating unit represented by the general formula (1) is less than the lower limit described above, the properties and physical properties when the film is used for glass substitution or optical use are reduced.

Such a polyimide is preferable as long as it can dissolve in a cast solvent having a low boiling point. If the film contains such a polyimide, it is also possible to manufacture it more easily. The casting solvent used herein preferably has a boiling point of 200 占 폚 or lower (more preferably 200 占 폚 or lower) in view of solubility, volatility, transparency, removability, film formability, productivity, industrial availability, recyclability, Preferably 20 to 150 캜, more preferably 30 to 120 캜, particularly preferably 40 to 100 캜, and most preferably 60 to 100 캜). The solvent having a boiling point of 200 DEG C or lower is more preferably a halogen solvent having a boiling point of 200 DEG C or lower and more preferably dichloromethane (methylene chloride), trichloromethane (chloroform), carbon tetrachloride, dichloroethane, trichlorethylene , Tetrachloroethane, chlorobenzene and o-dichlorobenzene are more preferable, and dichloromethane (methylene chloride) and trichloromethane (chloroform) are particularly preferable. These cast solvents may be used singly or in combination of two or more. In addition, from the viewpoint that the solubility of the obtained polyimide in the cast solvent is higher, R ¹⁰ in the general formula (1) is preferably the same as the general formula (101), (102), (103) 105), (106) and (107).

In addition, the polyimide preferably has an imidization ratio of 90% or more, more preferably 95% or more, and particularly preferably 96 to 100%. If the imidization rate is less than the lower limit described above, there is a tendency that the heat resistance is lowered, the color is visible, or the film looks and swells at the time of heating.

The imidization rate can be calculated as follows. That is, the polyimide to be measured is dissolved in a medium-soluble medium such as deuterated chloroform (preferably deuterated chloroform), and ¹ H-NMR measurement is carried out. From the ¹ H-NMR graph, 10 ppm H and 12 ppm (12 ppm +/- 1 ppm) of COOH. In this case, the enemy secretion (imidization ratio), first, with respect to the acid dianhydride and the diamine of the starting materials, and they prepare a sample dissolved in a moderate sheet (such as DMSO-d ₆₎ is soluble, and their ¹ H- in the graph of the measurement of NMR spectra, respectively, and their ¹ H-NMR, to obtain the position (chemical shift) and the integral value and the position of the diamine of the H (chemical shift) and the integral of the acid dianhydride water H, dianhydride of water such acid Using the H position, the integral value, and the H position and integral value of the diamine as a reference, it was found that the integral value of H of NH near 10 ppm and H of COOH near 12 ppm in the ¹ H-NMR graph of the polyimide to be measured The value calculated by relative comparison is employed. In the measurement of the imidization rate, the amount of polyimide to be measured for ¹ H-NMR spectrum is set so as to be 0.01 to 5.0 mass% with respect to the medium-soluble (preferably deuterated chloroform) The amount of dianhydride and the amount of diamine are each 0.01 to 5.0% by mass based on the solubilizing agent (DMSO-d _6, etc.) available. In measuring the imidization rate, the amount of polyimide, the amount of acid dianhydride in the starting compound, and the amount of diamine (the above concentration) are measured at the same concentration. For the ¹ H-NMR measurement, an NMR measuring device (trade name: UNITY INOVA-600, manufactured by VARIAN) is used as a measuring device.

The polyimide preferably has a 5% weight reduction temperature of 400 캜 or higher, more preferably 450 to 550 캜. If the 5% weight reduction temperature is below the lower limit, sufficient heat resistance tends to be difficult to achieve. On the other hand, if the 5% weight reduction temperature is exceeded, it tends to be difficult to produce polyimide having such properties. The 5% weight reduction temperature was set at a scanning temperature of 30 ° C to 550 ° C while heating at 10 ° C / min while flowing a nitrogen gas under a nitrogen gas atmosphere, and the weight of the sample used was 5 % ≪ / RTI > For this measurement, for example, a thermogravimetric analyzer (" TG / DTA220 " manufactured by SII Nanotechnology Co., Ltd.) may be used as the measuring apparatus.

The polyimide preferably has a glass transition temperature (Tg) of 250 캜 or higher, more preferably 300 to 500 캜. When the glass transition temperature (Tg) is less than the lower limit, sufficient heat resistance tends to be difficult to achieve. On the other hand, when the upper limit is exceeded, it tends to be difficult to produce polyimide having such properties. The glass transition temperature (Tg) can be measured at the same time by using a thermomechanical analyzer (trade name "TMA8311" manufactured by Rigaku Corporation) as a measuring apparatus and measuring the softening temperature. In measuring the glass transition temperature, it is preferable to carry out the measurement by scanning in the range of 30 DEG C to 550 DEG C under the nitrogen atmosphere at the temperature raising rate of 5 DEG C / min.

The polyimide preferably has a softening temperature of 250 to 550 占 폚, more preferably 350 to 550 占 폚, and still more preferably 360 to 510 占 폚. When the softening temperature is lower than the lower limit described above, the heat resistance is lowered. For example, in the case of using a polyimide film as a substrate for a transparent electrode of a solar cell, a liquid crystal display device, or an organic EL display device, It is difficult to sufficiently suppress deterioration (such as occurrence of cracks) in quality of such a film (substrate) in a heating process. On the other hand, when the upper limit is exceeded, when the polyimide is produced, Sufficient solid phase polymerization reaction does not proceed at the same time as the condensation reaction, and when the film is formed, the film tends to become rather fragile.

The softening temperature of such a polyimide can be measured in the following manner. That is, a film containing polyimide having a size of 5 mm in length, 5 mm in width, and 0.013 mm (13 탆) in thickness was prepared as a measurement sample. Using a thermomechanical analyzer (trade name "TMA8311" (Glass transition temperature (Tg)) was obtained by infiltrating a transparent quartz pin (tip diameter: 0.5 mm) into the film under the condition of a temperature range of 30 ° C to 550 ° C by employing the conditions of a temperature rise rate of 5 ° C / (Which can be measured by the so-called " pennation " method). In this measurement, the softening temperature is calculated based on the measurement data in accordance with the method described in JIS K 7196 (1991).

As the polyimide for forming such a film, the thermal decomposition temperature (Td) is preferably 450 ° C or higher, and more preferably 480 ° C to 600 ° C. If the thermal decomposition temperature (Td) is less than the lower limit, sufficient heat resistance tends to be difficult to achieve. On the other hand, when the upper limit is exceeded, it tends to be difficult to produce polyimides having such properties. The thermal decomposition temperature (Td) was measured using a TG / DTA 220 thermogravimetric analyzer (manufactured by SII Nanotechnology Co., Ltd.) under a nitrogen atmosphere at a heating rate of 10 ° C / min. It can be obtained by measuring the temperature at which the tangent line intersects.

The number average molecular weight (Mn) of such a polyimide is preferably 1,000 to 1,000,000, more preferably 10,000 to 500,000 in terms of polystyrene. When the number average molecular weight is less than the lower limit described above, not only sufficient heat resistance becomes difficult to achieve, but the polymer does not sufficiently precipitate from the polymerization solvent at the time of production, and it becomes difficult to obtain polyimide efficiently. On the other hand, , Viscosity is increased, it takes a long time to dissolve, or a large amount of solvent is required, which tends to make processing difficult.

The weight average molecular weight (Mw) of the polyimide forming such a film is preferably 1,000 to 5,000,000 in terms of polystyrene. The lower limit of the numerical value range of the weight average molecular weight (Mw) is more preferably 5000, further preferably 10000, particularly preferably 20,000. The upper limit value of the numerical value range of the weight average molecular weight (Mw) is more preferably 5,000,000, more preferably 500,000, and particularly preferably 100,000. When the weight average molecular weight is less than the lower limit described above, not only sufficient heat resistance becomes difficult to achieve, but the polymer does not sufficiently precipitate from the polymerization solvent at the time of production, and it becomes difficult to obtain polyimide efficiently. On the other hand, , The viscosity is increased and it takes a long time to dissolve it, or a large amount of solvent is required, so that processing tends to become difficult.

The molecular weight distribution (Mw / Mn) of the polyimide is preferably 1.1 to 5.0, more preferably 1.5 to 3.0. If the molecular weight distribution is less than the above lower limit, it tends to be difficult to produce. On the other hand, when the upper limit is exceeded, it tends to be difficult to obtain a uniform film. The molecular weight (Mw or Mn) or the molecular weight distribution (Mw / Mn) of the polyimide was measured by a gel permeation chromatography (GPC) measuring apparatus (DG-2080-54 manufactured by JASCO, Column: oven: 860-CO, RI detector manufactured by JASCO Corporation: RI-2031 manufactured by JASCO Corporation, Column: PU-2080 manufactured by JASCO, interface: LC-NetII / ADC manufactured by JASCO Corporation Column: GPC column KF- The data measured using a chloroform solvent (flow rate: 1 mL / min.) At a temperature of 40 DEG C can be obtained by converting the data into polystyrene.

The polyimide preferably has a coefficient of linear expansion of 0 to 100 ppm / K, more preferably 10 to 70 ppm / K. When the coefficient of linear expansion exceeds the upper limit, there is a tendency that peeling tends to occur due to thermal history when a composite material is combined with a metal or an inorganic material having a coefficient of linear expansion of 5 to 20 ppm / K. If the coefficient of linear expansion is less than the above lower limit, the solubility is lowered and the film property tends to be lowered.

As a method for measuring the coefficient of linear expansion of such polyimide, a polyimide film having a size of 76 mm in length, 52 mm in width and 13 m in thickness was formed, and then the film was vacuum dried (120 ° C for 1 hour) (49 mN) at a temperature raising rate of 5 deg. C / min under a nitrogen atmosphere using a thermomechanical analyzer (trade name "TMA8310" manufactured by Rigaku Corporation) as a measuring device, Min, a change in length in the longitudinal direction of the sample at 50 ° C to 200 ° C is measured, and a value obtained by obtaining an average value of change in length per 1 ° C in a temperature range of 50 ° C to 200 ° C .

Such a polyimide may contain other repeating units as long as the effect of the present invention is not impaired. Such other repeating units are not particularly limited as long as they are usable as, for example, polyimides.

The polyimide film of the present invention comprises a polyimide containing the repeating unit represented by the general formula (1) as described above, and further has a retardation (Rth) in the thickness direction measured at a wavelength of 590 nm, Is a film of -100 to 100 nm in terms of a thickness of 10 mu m. When the retardation (Rth) value in the thickness direction exceeds the upper limit, the contrast decreases and the viewing angle tends to deteriorate when used in a display device. Further, the retardation (Rth) in the thickness direction of the polyimide film is more preferably -50 to 50 nm, more preferably -25 to 25 nm, in terms of a thickness of 10 mu m. When the retardation (Rth) value in the thickness direction is out of the above-mentioned range, the contrast is lowered and the viewing angle tends to deteriorate when used in a display device. When the above-mentioned value is within the range, the effect of suppressing the contrast reduction and improving the viewing angle tends to be higher when used in a display device.

The " retardation (Rth) in the thickness direction " of the polyimide film of the present invention can be measured by measuring the refractive index of the polyimide film measured by the following method using a trade name " AxoScan " manufactured by AXOMETRICS (589 nm) was input to the measurement apparatus, and then the retardation in the thickness direction of the polyimide film was measured using light having a wavelength of 590 nm under the conditions of a temperature of 25 ° C and a humidity of 40% Based on the retardation measurement value (measured value by automatic measurement (automatic calculation) of the measuring device) of the retardation value of the film. The size of the polyimide film of the measurement specimen is not particularly limited, since it is larger than the photometric unit (diameter: about 1 cm) of the stage of the measuring instrument. Preferably, the size is 76 mm in length, 52 mm in width and 13 m in thickness Do.

The value of " the refractive index (589 nm) of the polyimide film " used for measuring the retardation (Rth) in the thickness direction includes the same kind of polyimide as the polyimide forming the film to be the object of measurement of retardation The unstretched film is used as a measurement sample (and when the film to be measured is an unstretched film, the film can be directly used as a measurement sample), and as a measuring apparatus (NAR-1T SOLID " manufactured by Atago Co., Ltd.) was used, and a light source of 589 nm was used. Under a temperature condition of 23 占 폚, an in-plane direction of the measurement specimen ) Can be obtained by measuring the refractive index with respect to light of 589 nm. In addition, since the sample to be measured is unstretched, the refractive index in the in-plane direction of the film becomes constant in any direction in the plane, and the inherent refractive index of the polyimide can be measured by measuring the refractive index (also, Nx = Ny when the refractive index in the direction of the delay axis in the plane is Nx and the refractive index in the in-plane direction perpendicular to the retardation axis direction is Ny since the measurement sample is unstretched). Thus, the inherent refractive index (589 nm) of the polyimide is measured using an unstretched film, and the obtained measurement value is used for measurement of retardation (Rth) in the thickness direction. Here, the size of the polyimide film of the measurement sample may be any size as long as it can be used in the refractive index measuring apparatus, and is not particularly limited, and may be a square having a side of 1 cm (lengthwise and widthwise 1 cm) and a thickness of 13 탆.

The polyimide film is preferably a film having a sufficiently high transparency, and more preferably 80% or more (more preferably 85% or more, particularly preferably 87% or more) in total light transmittance. This total light transmittance can be easily achieved by appropriately selecting the kind of polyimide or the like. As the total light transmittance, a polyimide film having a size of 76 mm in length, 52 mm in width and 13 m in thickness was formed as a sample for measurement, and a haze meter NDH- Quot; 5000 "

The shape of such a polyimide film may be a film type, and is not particularly limited, and can be suitably designed in various shapes (eg, a disc shape, a cylindrical shape (a film is processed into a cylindrical shape), etc.).

The thickness of the polyimide film of the present invention is not particularly limited, but is preferably 1 to 500 占 퐉, more preferably 10 to 200 占 퐉. If the thickness is less than the lower limit described above, the strength tends to be lowered and handling becomes difficult. On the other hand, when the thickness is more than the upper limit, a plurality of coatings may be required or processing may be complicated .

Further, since the polyimide film of the present invention has sufficiently high transparency and heat resistance, it can be used as a film for a flexible wiring board, a heat-resistant insulating tape, a wire enamel, a protective coating for a semiconductor, a liquid crystal alignment film, , Substrates for displays (substrates for displays such as TFT substrates and transparent electrode substrates), organic EL lighting films, flexible substrate films, flexible organic EL substrate films, flexible transparent conductive films, transparent conductive films for organic thin film solar cells, Type solar cell, a flexible gas barrier film, a film for a touch panel, a front film for a flexible display, a back film for a flexible display, and the like. In addition, the polyimide film of the present invention has a sufficiently small absolute value of the retardation (Rth) in the thickness direction. Therefore, in view of the improvement of the contrast and the viewing angle, A substrate for display such as an electrode substrate (a transparent conductive film for organic EL, etc.)).

The method for producing such a polyimide film is not particularly limited, and in order to produce a film comprising the polyimide containing the repeating unit, the following general formula (2)

Wherein R ¹ , R ² , R ³ and n are the same as R ¹ , R ² , R ³ and n in the general formula (1)

Tetracarboxylic acid dianhydride represented by the following general formulas (301) to (308):

And the polyimide film is subjected to a reaction by appropriately employing a known method (for example, a method for producing a polyimide described in International Publication No. 2011/099518, International Publication No. 2014/034760) May be employed. As a method for producing such a polyimide film, there can be mentioned a method in which a tetracarboxylic acid dianhydride represented by the general formula (2) and an aromatic (meth) acrylate represented by the general formulas (301) to (308) (4): < EMI ID =

[Equation (4) of, ^{R 1, R 2, R 3} , n R in the above general formula (1) of ^{R 1, R 2, R 3} , the same as n, and (also his right above general formula (1) ^{1, R 2, R 3,} ( R ¹⁰ is the same as in FIG. 1) (also his right above general formula (1) is the same as n), R ¹⁰ is the same as R ¹⁰ in the general formula);

, A polyamic acid solution containing the polyamic acid is applied on the surface of a substrate (e.g., a glass substrate or the like), and then the polyamic acid is imidized (A) of forming a film comprising a polyimide containing the repeating unit represented by the above general formula (1), which is laminated on the substrate, can be suitably used.

Regarding the tetracarboxylic dianhydride represented by the general formula (2), R ¹ , R ² and R ³ in the formula (2) are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, And n is an integer of 0 to 12, R ¹ , R ² , R ³ and n in the general formula (2) are the same as R ¹ , R ² , R ³ and n in the general formula (1) R ¹ , R ² , R ³ , n. The method for producing the tetracarboxylic acid dianhydride represented by the general formula (2) is not particularly limited and a known method can be suitably employed. For example, the method described in International Publication No. 2011/099517 Or the method described in International Publication No. 2011/099518 may be employed.

The tetracarboxylic acid dianhydride represented by the general formula (2) is preferably a tetracarboxylic dianhydride represented by the following general formula (5): ????????

[Equation (5) of, R ^1, R ^2, R ^3, n is the same as the above general formula (2) in ^{R 1, R 2, R 3} , n]

(A) represented by the following general formula (6):

[Formula (6) ^{of, R 1, R 2, R} 3, n are the same as ^{R 1, R 2, R 3} , n in the formula (2);

(B), and the total amount of the compounds (A) and (B) is preferably at least 90 mol%. The compound (A) represented by the general formula (5) is a compound represented by the general formula (2) in which two norbornane groups are trans-arranged and the carbonyl group of the cycloalkanone is arranged in the steric configuration of each of the two norbornane groups. ) ≪ / RTI > of the tetracarboxylic dianhydride. The compound (B) represented by the general formula (6) is a compound represented by the general formula (1) in which two norbornane groups are arranged in the cis and the carbonyl group of the cycloalkanone is arranged in the three- Is an isomer of a tetracarboxylic dianhydride represented by the following formula (2). The production method of the tetracarboxylic dianhydride containing such isomers in the above ratios is not particularly limited, and a known method can be suitably employed. For example, the method described in International Publication No. 2014/034760 is suitably applied .

The aromatic diamines represented by the general formulas (301) to (308) include bis [4- (3-aminophenoxy) phenyl] sulfone, 1,3- Bis (4-aminophenoxy) benzene, 4,4'-diamino-2,2-bis (trifluoromethyl) biphenyl, 2,2- ] Propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, bis [4- Phenoxy) biphenyl.

Of these aromatic diamines, bis [4- (3-aminophenoxy) phenyl] sulfone, 1,3-bis (3-aminophenoxy) benzene , 4,4'-diamino-2,2-bis (trifluoromethyl) biphenyl (more preferably bis [4- (3-aminophenoxy) (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene) is preferable, the absolute value of Rth is sufficiently small, (4-aminophenoxy) phenyl] sulfone, 4,4'-diamino-2,2-bis (trifluoromethyl) biphenyl, bis [4- Aminophenoxy) phenyl] sulfone (more preferably bis [4- (4-aminophenoxy) phenyl] sulfone, 4,4'-diamino-2,2-bis (trifluoromethyl) [4- (3-aminophenoxy) phenyl] sulfone) is preferable. These aromatic diamines may be used singly or in combination of two or more. Commercially available aromatic diamines may be appropriately used.

Examples of the polymerization solvent used in the method (A) include a method of dissolving both the tetracarboxylic acid dianhydride represented by the general formula (2) and the aromatic diamine represented by the general formulas (301) to (308) It is preferable that the organic solvent is an organic solvent.

Examples of such an organic solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide,? -Butyrolactone, Non-protonic polar solvents such as methyl urea, 1,3-dimethyl-2-imidazolidinone, hexamethylphosphoric triamide and pyridine; phenol-based solvents such as m-cresol, xylenol, phenol, and halogenated phenol; Ether solvents such as tetrahydrofuran, dioxane, cellosolve, glyme and diglyme; Aromatic solvents such as benzene, toluene and xylene; Ketone solvents such as cyclopentanone and cyclohexanone; And nitrile solvents such as acetonitrile and benzonitrile. These polymerization solvents (organic solvents) may be used singly or in combination of two or more.

In the method (A), the ratio of the tetracarboxylic acid dianhydride represented by the general formula (2) to the aromatic diamine represented by the general formulas (301) to (308) The acid anhydride group of the tetracarboxylic dianhydride represented by the general formula (2) is preferably 0.2 to 2 equivalents, more preferably 0.8 to 1.2 equivalents based on 1 equivalent of the amino group of the aromatic diamine represented by the general formulas (1) to (308) More preferably in an equivalent amount. If the ratio is less than the lower limit described above, the polymerization reaction does not progress efficiently and a polyamide acid with a high molecular weight tends not to be obtained. On the other hand, when the upper limit is exceeded, a polyamide acid having a high molecular weight Tend not to.

The amount of the polymerization solvent (organic solvent) to be used in the method (A) is not particularly limited as long as the amount of the tetracarboxylic acid dianhydride represented by the general formula (2) and the total amount of the tetracarboxylic acid dianhydride represented by the general formulas (301) It is preferable that the total amount of the aromatic diamine is 0.1 to 50 mass% (more preferably 10 to 30 mass%) with respect to the total amount of the reaction solution. If the amount of the organic solvent used is less than the lower limit described above, the polyamic acid can not be efficiently obtained. On the other hand, if the amount exceeds the upper limit, stirring tends to be difficult due to high viscosity.

In the method (A), the method of reacting the tetracarboxylic acid dianhydride represented by the general formula (2) with the aromatic diamine represented by the general formulas (301) to (308) is not particularly limited A known method capable of reacting an aromatic diamine with a tetracarboxylic dianhydride can be suitably employed. For example, an aromatic diamine compound may be used in an inert atmosphere such as nitrogen, helium, or argon under atmospheric pressure A method in which a tetracarboxylic acid dianhydride represented by the above-mentioned general formula (2) is added to the solution and then the solution is allowed to react for 10 to 48 hours. In addition, in this reaction, the temperature condition is preferably set to about -20 to 100 캜. If the reaction time or the reaction temperature is less than the lower limit described above, it tends to be difficult to react sufficiently. On the other hand, when the upper limit is exceeded, the probability of incorporation of a substance (oxygen or the like) deteriorating the polymer is increased and the molecular weight tends to decrease have.

R ¹ , R ² , R ³ and n in the general formula (4) are the same as R ¹ and R in the general formula (1) ² , R ³ , n, and their suitable examples are the same as R ¹ , R ² , R ³ , n in the general formula (1). Further, R ¹⁰ in the formula (4) is the same as R ¹⁰ in the formula (1), the same is also suitable for his. Thus, R ¹⁰ in the general formula (4) is one kind of group selected from the groups represented by the general formulas (101) to (108).

In the method (A), the polyamic acid to be formed as an intermediate preferably has an intrinsic viscosity [?] Of 0.05 to 3.0 dL / g, more preferably 0.1 to 2.0 dL / g. When the intrinsic viscosity [?] Is less than 0.05 dL / g, the resulting film tends to be fragile when the film-like polyimide is produced using the same, while when it exceeds 3.0 dL / g, the viscosity is too high The processability is lowered, and it becomes difficult to obtain a uniform film when, for example, a film is produced.

The intrinsic viscosity [?] Of such a polyamic acid can be measured in the following manner. Namely, first, N, N-dimethylacetamide is used as a solvent, and the polyamic acid is dissolved in the N, N-dimethylacetamide so that the concentration becomes 0.5 g / dL to obtain a measurement sample (solution) . Then, the viscosity of the sample to be measured is measured using a dynamic viscometer under the temperature condition of 30 DEG C by using the sample to be measured, and the obtained value is adopted as intrinsic viscosity [?]. As this dynamic viscometer, an automatic viscosity measuring device (trade name: VMC-252) manufactured by LIGO Co., Ltd. is used.

Furthermore, the substrate used in the method (A) is not particularly limited, and a substrate including a known material which can be used for forming a film, depending on the shape of the film including the desired polyimide , A glass plate or a metal plate) can be suitably used.

Further, in the method (A), the method of applying the solution of the polyamic acid on the substrate is not particularly limited, and examples thereof include a spin coating method, a spray coating method, a dip coating method, Known methods such as a printing method, a screen printing method, an iron plate printing method, a die coating method, a curtain coating method, and an ink jet method can be suitably employed.

In the method (A), the method of imidizing the polyamic acid is not particularly limited, and any method can be used to imidize the polyamic acid. The method is not particularly limited, 099518, the method of imidization described in International Publication No. 2014/034760, etc.) can be appropriately employed. As a method for imidizing the polyamic acid, for example, a method in which the polyamic acid containing the repeating unit represented by the general formula (4) is heated at a temperature of 60 to 400 캜 (more preferably 60 to 370 캜, Is in the range of 150 to 360 DEG C), or a method of imidizing it by using a so-called " imidation agent " is preferably employed.

In this method (A), the polyamic acid containing the repeating unit represented by the general formula (4) is not isolated before the polyamic acid is imidized, and the polyamic acid in the polymerization solvent (organic solvent) The reaction solution obtained by reacting the tetracarboxylic acid dianhydride represented by the general formula (2) with the aromatic diamine represented by the general formulas (301) to (308) A reaction liquid containing a polyamic acid containing a repeating unit) is used as it is, the reaction solution is coated on a substrate, followed by drying treatment to remove the solvent and heat treatment to imidize . The temperature condition in such a drying process is preferably 0 to 180 캜, more preferably 60 to 150 캜. The polyamide acid containing the repeating unit represented by the general formula (4) may be isolated from the reaction mixture and used. In this case, the method of isolating the polyamic acid is not particularly limited, A method of isolating it as a re-precipitate, or the like may be employed.

By this method (A), a polyimide film can be obtained in a state of being laminated on a substrate. When the polyimide film thus obtained is peeled off from the substrate and recovered, the peeling method thereof is not particularly limited, and a known method can be suitably employed. For example, a high temperature water (for example, A method in which a polyimide film is peeled off from a substrate by immersing a laminate in which a polyimide film is laminated on a substrate in water may be employed.

[Organic electroluminescent device]

The organic electroluminescent device of the present invention comprises the polyimide film of the present invention.

As such an organic electroluminescent device, for example, other than the above-mentioned polyimide film of the present invention, the other constitution is not particularly limited, and a well-known constitution can suitably be used. Such an organic electroluminescent device is not particularly limited, but it is preferable that the polyimide film of the present invention is provided as a substrate for laminating a transparent electrode, for example, from the viewpoint of improving the contrast and the viewing angle.

Hereinafter, an embodiment capable of being suitably used as the organic electroluminescent element (organic EL element) of the present invention will be briefly described with reference to the drawings. In the following description and drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant description is omitted.

1 is a schematic longitudinal sectional view of a preferred embodiment of an organic electroluminescence device (organic EL device) of the present invention. The organic EL device 1 of the embodiment shown in Fig. 1 is formed by stacking a polyimide film 11, a gas barrier layer 12, a transparent electrode layer 13, an organic layer 14 and a metal electrode layer 15 Respectively.

The polyimide film 11 in the organic EL device includes the polyimide film of the present invention. In this embodiment, such a polyimide film 11 is used as a substrate of an organic EL element (a substrate for laminating a transparent electrode).

In addition, the gas barrier layer 12 is a layer suitably used for suppressing the permeation of gas into the device, making the permeation preventing performance of the gas (including water vapor) higher. The gas barrier layer 12 is not particularly limited. For example, a layer containing an inorganic substance such as SiN, SiO ₂ , SiC, SiO _x N _y , TiO ₂ , Al ₂ O ₃ , Can be used to make. Such a gas barrier layer 12 may be formed by appropriately arranging (forming) a layer having a known gas barrier property on the polyimide film 11.

Although the thickness of the gas barrier layer 12 is not particularly limited, it is preferably in the range of 0.01 to 5000 탆, and more preferably in the range of 0.1 to 100 탆. If the thickness is less than the lower limit described above, sufficient gas barrier property tends not to be obtained. On the other hand, if the thickness exceeds the upper limit, the thickness tends to be heavy to lose the characteristics such as flexibility and flexibility.

The transparent electrode layer 13 is a layer used as a transparent electrode of the organic EL device. The material of the transparent electrode layer 13 is not particularly limited as long as it can be used for the transparent electrode of the organic EL element. For example, indium oxide, zinc oxide, tin oxide, and indium tin oxide (ITO ), Gold, platinum, silver and copper are used. Of these, ITO is preferable from the viewpoint of balance between transparency and conductivity.

The thickness of the transparent electrode layer 13 is preferably in the range of 20 to 500 nm. If the thickness is less than the lower limit described above, the conductivity tends to become insufficient. On the other hand, if the thickness exceeds the upper limit, the transparency becomes insufficient and the emitted EL light tends to be unable to be sufficiently extracted to the outside.

A so-called thin film transistor (TFT) layer may be formed between the gas barrier layer 12 and the transparent electrode layer 13. By forming the TFT layer in this manner, it becomes possible to form an apparatus (TFT element) having a transparent electrode connected to the TFT. The material (such as oxide semiconductor, amorphous silicon, polysilicon, organic transistor, etc.) and the structure of such a TFT layer are not particularly limited, and can be suitably designed based on the configuration of a known TFT. When a TFT layer is provided on the laminate of the polyimide film 11 and the gas barrier layer 12, these laminated bodies can be used as a so-called TFT substrate. The method of manufacturing such a TFT layer is not particularly limited and a well-known method can be suitably employed. For example, a manufacturing method such as a low-temperature polysilicon method, a high-temperature polysilicon method, an amorphous silicon method, or an oxide semiconductor method is employed You can.

The organic layer 14 is not particularly limited as long as it can be used for forming the organic EL element, and the structure that can be used for the organic layer of the known organic EL element can be suitably used. The constitution of the organic layer 14 is not particularly limited, and a well-known structure can be appropriately adopted. For example, a laminate including a hole transporting layer, a light emitting layer and an electron transporting layer may be an organic layer.

As the material of such a hole transporting layer, a known material capable of forming a hole transporting layer can be suitably used. For example, naphthyldiamine (? -NPD), triphenylamine, triphenyldiamine derivative (TPD) Pyrazoline, styrylamine, hydrazone, triphenylmethane, carbazole and the like can be used.

The light-emitting layer is a layer in which electrons and holes injected from an electrode layer and the like are recombined to emit light. The material of such a light-emitting layer is not particularly limited and a known material capable of forming a light-emitting layer of an organic EL device can be suitably used. For example, a material obtained by doping 4,4'-N, N'-dicarbazole-biphenyl (CBP) with a trisphenylpyridinato isridium (III) complex (Ir (ppy) ₃ ) hydroxyquinoline aluminum (Alq _3, green, low molecular weight), bis (8-hydroxyethyl) quinone naldin aluminum phenoxide (Alq _'2 OPh, blue, low-molecular-weight), 5,10,15,20-tetraphenyl--21H, 23H (PFO, blue, high molecular weight), poly [2-methoxy-5- (2'-ethyl (MEH-CN-PPV, red, polymer), and fluorescent organic solids such as hexyloxy) -1,4- (1-cyanovinylene) phenylene] Known materials And can be suitably used.

The material for the electron transport layer is not particularly limited and a known material capable of forming an electron transport layer can be suitably used. For example, an aluminum quinolinol complex (Alq), a phenanthroline derivative, an oxadiazole derivative, Triazole derivatives, phenylquinoxaline derivatives, and silole derivatives.

In the case where the organic layer 14 is a laminate including a hole transporting layer, a light emitting layer and an electron transporting layer, the thickness of each layer of the hole transporting layer, the light emitting layer and the electron transporting layer is not particularly limited, but ranges from 1 to 50 nm (hole transporting layer) (Light emitting layer) of 5 to 200 nm and a range of 5 to 200 nm (electron transporting layer). The total thickness of the organic layer 14 is preferably in the range of 20 to 600 nm.

The metal electrode layer 15 is an electrode containing a metal. As the material of such a metal electrode, a material having a small work function can be suitably used, and although not particularly limited, for example, aluminum, MgAg, MgIn, and AlLi can be cited. The thickness of the metal electrode layer 15 is preferably in the range of 50 to 500 nm. If the thickness is less than the lower limit described above, the conductivity tends to deteriorate. On the other hand, when the thickness is more than the upper limit, peeling easily occurs or cracks tend to occur.

The method for producing such an organic EL device is not particularly limited. For example, after preparing the polyimide film of the present invention, the gas barrier layer, the transparent electrode, the organic layer And the metal electrode may be sequentially laminated.

The method for laminating the gas barrier layer 12 on the surface of the polyimide film 11 is not particularly limited and a known method such as a vapor deposition method and a sputtering method can be suitably employed. Among them, It is preferable to adopt a sputtering method from the viewpoint of the above. As a method for laminating the transparent electrode layer 13 on the surface of the gas barrier layer 12, a known method such as a vapor deposition method and a sputtering method can be suitably employed. Among them, from the viewpoint of forming a coherent film , And a sputtering method are preferably employed.

The method of laminating the organic layer 14 on the surface of the transparent electrode layer 13 is also not particularly limited. For example, when the organic layer is a laminate including the hole transport layer, the light emitting layer and the electron transport layer as described above , These layers may be sequentially stacked on the transparent electrode layer 13. The method of laminating the respective layers in the organic layer 14 is not particularly limited, and a known method can be appropriately used. For example, a vapor deposition method, a sputtering method, a coating method, or the like can be employed. Of these methods, from the viewpoint of sufficiently preventing decomposition, deterioration and denaturation of the organic layer, it is preferable to employ a vapor deposition method.

The method for laminating the metal electrode layer 15 on the organic layer 14 is not particularly limited and a known method can be appropriately used. For example, a vapor deposition method, a sputtering method, or the like can be employed. Of these methods, from the viewpoint of sufficiently preventing decomposition, deterioration and denaturation of the organic layer 14 formed earlier, it is preferable to adopt a vapor deposition method.

Further, by manufacturing the organic EL device in this manner, the organic EL device using the polyimide film 11 as a substrate for supporting the element portion can be formed. Therefore, It is possible to improve the flexibility and to make the flexibility high enough.

As described above, a preferred embodiment of the organic EL device of the present invention has been described. However, the organic EL device of the present invention is not limited to the above embodiment. For example, although in the above embodiment, the organic layer 14 includes a layered body of a hole transporting layer, a light emitting layer and an electron transporting layer, the form of the organic layer is not particularly limited, and the structure of a known organic layer is suitably employed An organic layer including, for example, a laminate of a hole injection layer and a light emitting layer; An organic layer including a laminate of a light emitting layer and an electron injection layer; An organic layer including a hole injecting layer, a luminescent layer, and an electron injecting layer; Or an organic layer including a laminate of a buffer layer, a hole transporting layer and an electron transporting layer, or the like. The material of each layer in another form of the organic layer is not particularly limited, and known materials can be suitably used. For example, as the material of the electron injection layer, a perylene derivative or the like may be used. As the material of the hole injection layer, a triphenylamine derivative or the like may be used, and as the material of the anode buffer layer, copper phthalocyanine, PEDOT and the like may be used . In addition, in the above embodiment, it may be a layer that is not disposed, or a layer that can be used for the organic EL device, and may be appropriately disposed. For example, from the viewpoint of facilitating charge injection or hole injection into the organic layer 14, A layer containing lithium fluoride (LiF), a metal fluoride such as Li ₂ O ₃ , an alkaline earth metal such as Ca, Ba, or Cs, or an organic insulating material is formed on the electrode layer 13 or the organic layer 14 .

[Organic electroluminescence display]

The organic electroluminescence display of the present invention comprises the polyimide film of the present invention.

As such an organic electroluminescence display (organic EL display), for example, in addition to the above-mentioned polyimide film of the present invention, the other constitution is not particularly limited, and a known constitution can suitably be used. As the organic EL display, for example, the polyimide film of the present invention can be used as a substrate for use in an organic EL display (for example, a substrate for stacking transparent electrodes (a substrate for stacking transparent electrodes), an organic EL display Such as a barrier substrate, a thin film transistor substrate, a sealing layer substrate, a negative electrode substrate, an organic semiconductor substrate, a positive electrode substrate, a direct current driving circuit substrate, a hard coating substrate, a front film substrate, a back film substrate, .

In addition, as the organic electroluminescence display (organic EL display) of the present invention, it is preferable that the polyimide film of the present invention is provided as a substrate for laminating a transparent electrode, for example, from the viewpoint of improving the contrast and the viewing angle. As such a transparent electrode lamination substrate, for example, a transparent electrode lamination substrate of an element (organic EL element) used for an organic EL display is preferable. Therefore, it is preferable that the organic EL display of the present invention includes the organic electroluminescence element (organic EL element) of the present invention.

Example

Hereinafter, the present invention will be described more specifically based on examples and comparative examples, but the present invention is not limited to the following examples.

First, a method for evaluating properties of the polyimide film and the like obtained in each of the Examples and Comparative Examples will be described.

<Identification of Molecular Structure>

The molecular structures of the compounds obtained by the respective Examples and Comparative Examples were identified by using an IR measuring device (trade name: FT / IR-4100, manufactured by Nihon Bunko KK) and an NMR measuring device (trade name: UNITY INOVA-600, manufactured by VARIAN) , And measuring the IR and NMR spectra.

&Lt; Measurement of intrinsic viscosity [?]

The intrinsic viscosity [eta] of the polyamic acid obtained as an intermediate in each of the Examples and Comparative Examples was measured using an automatic viscosimeter (trade name "VMC-252" manufactured by Rigaku Corporation) -Dimethylacetamide as a solvent at a concentration of 0.5 g / dL under a temperature condition of 30 캜.

&Lt; Measurement of Glass Transition Temperature (Tg) >

The glass transition temperature (Tg) of the compound (film forming compound) obtained by each example and each comparative example was measured using a polyimide film prepared in each of the examples and comparative examples, TMA8311 "manufactured by Rigaku Corporation), and the same method (same conditions) as the method of measuring the softening temperature described below was employed to measure the softening temperature at the same time.

&Lt; Measurement of softening temperature >

The softening temperature (softening point) of the compound (film forming compound) obtained by each example and each comparative example was measured using a polyimide film produced in each of the examples and comparative examples, and a thermomechanical analyzer Under the conditions of a temperature raising rate of 5 占 폚 / min and a temperature range of 30 占 폚 to 550 占 폚 (scanning temperature), using a transparent quartz pin (diameter of tip: 0.5 mm) at a pressure of 500 mN (measured by the so-called penetration method). In this measurement, the softening temperature was calculated on the basis of measurement data in accordance with the method described in JIS K 7196 (1991), except that the measurement sample was used.

&Lt; Measurement of 5% weight reduction temperature >

The 5% weight reduction temperature (Td5%) of the compound obtained by each of the examples and the like was measured by a thermogravimetric analyzer (manufactured by SII Nanotechnology Co., Ltd.) using the polyimide film prepared in each of the Examples and Comparative Examples TG / DTA220 &quot;) was used, the scanning temperature was set to 30 to 550 DEG C, and the sample was heated under a nitrogen gas atmosphere at a rate of 10 DEG C / min while flowing nitrogen gas to decrease the weight of the used sample by 5% &Lt; / RTI &gt;

&Lt; Measurement of total light transmittance >

The total light transmittance was measured in accordance with JIS K7361-1 (trade name, manufactured by NIPPON DENSHOKU KOGYO CO., LTD. Under the trade name of "Hazemeter NDH-5000") using the polyimide film prepared in each of the Examples and Comparative Examples Published in 1997).

<Measurement of Refractive Index>

The refractive index (refractive index with respect to light at 589 nm) of the polyimide film prepared in each of the examples and comparative examples was measured using a polyimide film (unstretched film) prepared in the same manner as in each of the examples and comparative examples, , A film having a square of 1 cm in both sides (1 cm in length and 1 cm in length) and having a thickness of 13 μm was cut out and used as a measurement sample, and a refractive index measuring apparatus (trade name "NAR-1T SOLID" available from Atago Co., Ltd.) (Intrinsic refractive index of polyimide) in the in-plane direction (direction perpendicular to the thickness direction) with respect to light of 589 nm under a temperature condition of 23 캜 using a light source of 589 nm.

&Lt; Retardation in thickness direction (Rth) >

The retardation (Rth) in the thickness direction was measured using a polyimide film (length: 76 mm, width: 52 mm, thickness: 13 탆) produced in each of the examples and comparative examples as it is as a measurement sample. The refractive index of each polyimide film (refractive index with respect to light at 589 nm of the film obtained by measurement of the refractive index described above) was input using a trade name &quot; AxoScan &quot; : 40%, light having a wavelength of 590 nm was used and the retardation in the thickness direction was measured. Thereafter, using the retardation measurement value (measured value obtained by automatic measurement of the measuring apparatus) in the thickness direction obtained, Converted into a retardation value per 10 mu m thickness.

(Example 1)

&Lt; Preparation process of tetracarboxylic dianhydride >

According to the method described in Synthesis Example 1, Example 1 and Example 2 of International Patent Publication No. 2011/099518, a compound represented by the following general formula (7):

Tetracarboxylic dianhydride (norbornane-2-spiro-a-cyclopentanone-a'-spiro-2 &quot; -norbornane-5,5 &quot;, 6,6 & Carboxylic acid dianhydride) was prepared.

&Lt; Production process of polyamic acid >

First, a 30-ml three-necked flask was heated with a heat gun and sufficiently dried. Subsequently, the atmosphere gas in the sufficiently dried three-necked flask was replaced with nitrogen, and the inside of the three-necked flask was changed to nitrogen atmosphere. Subsequently, 0.3892 g (0.90 mmol) of bis [4- (3-aminophenoxy) phenyl] sulfone was added to the above three-necked flask, (BAPS-M) was dissolved in the N, N-dimethylacetamide by adding 2.7 g of N, N-dimethylacetamide, followed by stirring to obtain a dissolution liquid.

Subsequently, 0.3459 g (0.90 mmol) of the compound represented by the general formula (7) was added to a three-necked flask containing the above dissolution liquid, and the mixture was stirred at room temperature (25 ° C) for 12 hours Followed by stirring to obtain a reaction solution. Thus, a polyamic acid was formed in the reaction solution.

A portion of this reaction solution (N, N-dimethylacetamide solution of polyamic acid: polyamic acid solution) was used to prepare an N, N-dimethylacetamide solution having a polyamic acid concentration of 0.5 g / And the intrinsic viscosity [?] Of the polyamic acid as the reaction intermediate was measured as described above. As a result, the intrinsic viscosity [?] Of the polyamic acid was found to be 0.22 dL / g.

&Lt; Process for producing polyimide-containing film &

A large-sized slide glass (trade name: "S9213", manufactured by Matsunami Glass Co., Ltd., length: 76 mm, width: 52 mm, thickness: 1.3 mm) was prepared as a glass substrate, and the reaction solution ) Was spin-coated on the surface of the glass substrate so that the thickness of the coated film after heat-setting was 13 占 퐉, thereby forming a coating film on the glass substrate. Thereafter, the glass substrate on which the coating film was formed was placed on a hot plate at 60 DEG C and allowed to stand for 2 hours, and the solvent was evaporated from the coating film (solvent removal treatment).

After the solvent removal treatment, the glass substrate on which the coating film was formed was placed in an inert gas oven in which nitrogen flowed at a flow rate of 3 L / min. Under the nitrogen atmosphere, , And then heated at a temperature of 135 ° C for 0.5 hours and further heated at a temperature condition of 350 ° C for 1 hour to cure the coating film and a thin film containing polyimide Polyimide film) -coated polyimide-coated glass.

Subsequently, the polyimide-coated glass thus obtained was immersed in hot water at 90 占 폚 and the polyimide film was peeled off from the glass substrate to obtain a polyimide film (film having a size of 76 mm long, 52 mm wide and 13 mm thick) .

Further, in order to identify the molecular structure of the compound forming the polyimide film thus obtained, the IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by Nihon Bunko K.K.). The IR spectrum obtained as a result of this measurement is shown in Fig. As is clear from the results shown in Fig. 2, C = O stretching vibration of the imidocarbonyl was observed at 1706 cm &lt; ^-1 &gt; in the compound constituting the film formed in Example 1. [ From the molecular structure identified based on these results and the like, it was confirmed that the obtained film was a film containing polyimide. Further, for the obtained film, the refractive index with respect to the light of 589 nm was measured in the in-plane direction of the polyimide as described above, and as a result, the refractive index was 1.6120.

Further, the obtained polyamide from a polyimide, a kind of the monomer used, and the formula repeating unit represented by formula (1): (wherein in R ^1, R ^2, both R ³ are hydrogen atoms, n is 2, R ¹⁰ is the And the content of the repeating unit represented by the general formula (101)) was 100 mol% based on the total repeating units. Further, regarding the obtained polyimide film, the evaluation results of the characteristics (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Example 2)

(3-aminophenoxy) benzene was used instead of bis [4- (3-aminophenoxy) phenyl] sulfone as an aromatic diamine in the production process of polyamic acid. : 1,3,3-BAB: an aromatic diamine represented by the above-mentioned general formula (302)) manufactured by Tokyo Kasei Kogyo Co., Ltd., and further in the production process of a film containing polyimide, Was changed from 350 캜 to 300 캜, a polyimide film was obtained in the same manner as in Example 1. The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. Further, the obtained polyamide from a polyimide, a kind of the monomer used, and the formula repeating unit represented by formula (1): (wherein in R ^1, R ^2, both R ³ are hydrogen atoms, n is 2, R ¹⁰ is the Is a polyimide having a content ratio of 100 mol% based on the total repeating units. The results of measurement of the intrinsic viscosity [?] Of the polyamic acid obtained in the production process of the polyamic acid are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Example 3)

(4-aminophenoxy) benzene was used instead of bis [4- (3-aminophenoxy) phenyl] sulfone as an aromatic diamine in the production process of polyamic acid. : 1,3,4-BAB: an aromatic diamine represented by the above general formula (303)) manufactured by Wakayama Seika Kogyo Co., Ltd., and further in the production process of a film containing polyimide, The polyimide film was obtained in the same manner as in Example 1 except that the above-mentioned final heating temperature was changed from 350 占 폚 to 360 占 폚. The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. Further, the obtained polyamide from a polyimide, a kind of the monomer used, and the formula repeating unit represented by formula (1): (wherein in R ^1, R ^2, both R ³ are hydrogen atoms, n is 2, R ¹⁰ is the And the content of the repeating unit represented by the general formula (103)) was 100 mol% based on the total repeating units. The results of measurement of the intrinsic viscosity [?] Of the polyamic acid obtained in the production process of the polyamic acid are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Example 4)

In the process for producing a polyamic acid, it is also possible to use 4,4'-diamino-2,2'-bis (trifluoro (meth) acrylate) instead of bis [4- (0.2882 g, 0.90 mmol, manufactured by Tokyo Kasei Kabushiki Kaisha; 6FDA: aromatic diamine represented by the above general formula (304)) was used and stirred at room temperature (25 ° C) for 12 hours A polyimide film was obtained in the same manner as in Example 1 except that the reaction solution was obtained by stirring at 60 占 폚 for 12 hours in a nitrogen atmosphere. The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. Further, the obtained polyamide from a polyimide, a kind of the monomer used, and the formula repeating unit represented by formula (1): (wherein in R ^1, R ^2, both R ³ are hydrogen atoms, n is 2, R ¹⁰ is the And the content of the repeating unit represented by the general formula (104)) was 100 mol% based on the total repeating units. The results of measurement of the intrinsic viscosity [?] Of the polyamic acid obtained in the production process of the polyamic acid are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Example 5)

Bis [4- (4-aminophenoxy) phenyl] propane as an aromatic diamine in place of bis [4- (3-aminophenoxy) phenyl] A polyimide film was obtained in the same manner as in Example 1 except that 0.3695 g (0.90 mmol: BAPP: an aromatic diamine represented by the above-mentioned general formula (305)) of Tokyo Kasei Kabushiki Kaisha was used. The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. Further, the obtained polyamide from a polyimide, a kind of the monomer used, and the formula repeating unit represented by formula (1): (wherein in R ^1, R ^2, both R ³ are hydrogen atoms, n is 2, R ¹⁰ is the Is a polyimide having a content ratio of 100 mol% based on the total repeating units. The results of measurement of the intrinsic viscosity [?] Of the polyamic acid obtained in the production process of the polyamic acid are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Example 6)

Bis [4- (4-aminophenoxy) phenyl] hexa-ene as an aromatic diamine instead of using bis [4- (3-aminophenoxy) (BAPF: an aromatic diamine represented by the above general formula (306)) of 0.4666 g (0.90 mmol; manufactured by Tokyo Chemical Industry Co., Ltd.) as a fluorine-containing solvent, and further, in the production process of a film containing polyimide, A polyimide film was obtained in the same manner as in Example 1 except that the final heating temperature in the oven was changed from 350 占 폚 to 300 占 폚. The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. Further, the obtained polyamide from a polyimide, a kind of the monomer used, and the formula repeating unit represented by formula (1): (wherein in R ^1, R ^2, both R ³ are hydrogen atoms, n is 2, R ¹⁰ is the Is a polyimide having a content ratio of 100 mol% based on the total repeating units. The results of measurement of the intrinsic viscosity [?] Of the polyamic acid obtained in the production process of the polyamic acid are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Example 7)

(3-aminophenoxy) phenyl] sulfone was used instead of bis [4- (4-aminophenoxy) phenyl] sulfone as an aromatic diamine in the production process of polyamic acid. (BAPS: an aromatic diamine represented by the above-mentioned general formula (307)) was used instead of the polyimide film in Example 1, to obtain a polyimide film. The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. Further, the obtained polyamide from a polyimide, a kind of the monomer used, and the formula repeating unit represented by formula (1): (wherein in R ^1, R ^2, both R ³ are hydrogen atoms, n is 2, R ¹⁰ is the Is a polyimide having a content ratio of 100 mol% based on the total repeating units. The results of measurement of the intrinsic viscosity [?] Of the polyamic acid obtained in the production process of the polyamic acid are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Example 8)

(4-aminophenoxy) phenyl) sulfone was used instead of bis [4- (3-aminophenoxy) phenyl] sulfone as an aromatic diamine in the production process of polyamic acid 0.30 mmol: manufactured by Nippon Junyu Chemical Co., Ltd.: APBP: aromatic diamine represented by the above-mentioned general formula (308)) was used instead of the polyimide film. The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. Further, the obtained polyamide from a polyimide, a kind of the monomer used, and the formula repeating unit represented by formula (1): (wherein in R ^1, R ^2, both R ³ are hydrogen atoms, n is 2, R ¹⁰ is the And the content of the repeating unit represented by the general formula (108)) was 100 mol% based on the total repeating units. The results of measurement of the intrinsic viscosity [?] Of the polyamic acid obtained in the production process of the polyamic acid are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Comparative Example 1)

(8) shown below instead of using bis [4- (3-aminophenoxy) phenyl] sulfone as an aromatic diamine in the production process of polyamic acid,

Except that 0.2631 g (0.90 mmol; manufactured by Tokyo Kasei Kabushiki Kaisha: 1,4,4-BAB) of 1,4-bis (4-aminophenoxy) benzene represented by the following formula To obtain a polyimide film. The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. The results of measurement of the intrinsic viscosity [?] Of the polyamic acid obtained in the production process of the polyamic acid are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Comparative Example 2)

(9) shown below instead of using bis [4- (3-aminophenoxy) phenyl] sulfone as an aromatic diamine in the process for producing a polyamic acid,

Except that 0.1802 g (0.90 mmol: 4,4'-DDE manufactured by Tokyo Kasei K.K.) of 4,4'-diaminodiphenyl ether represented by the following formula (1) was used instead of the polyimide film &Lt; / RTI &gt; The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. The results of measurement of the intrinsic viscosity [?] Of the polyamic acid obtained in the production process of the polyamic acid are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Comparative Example 3)

(10) shown below instead of using bis [4- (3-aminophenoxy) phenyl] sulfone as an aromatic diamine in the process for producing a polyamic acid,

(0.90 mmol, manufactured by Nippon Junyaku Co., Ltd., DABAN) was used as the solvent, and further, in the production process of a film containing polyimide, the inner oven The polyimide film was obtained in the same manner as in Example 1 except that the above-mentioned final heating temperature was changed from 350 占 폚 to 380 占 폚. The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. The results of measurement of the intrinsic viscosity [?] Of the polyamic acid obtained in the production process of the polyamic acid are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Comparative Example 4)

Instead of using bis [4- (3-aminophenoxy) phenyl] sulfone as an aromatic diamine in the production process of a polyamic acid,

(25 ° C) at room temperature (25 ° C) in the presence of N, N'-bis (4-aminophenyl) terephthalamide (0.90 mmol, manufactured by NIPPON JOURNAL OF CHEMICAL INDUSTRIES, A polyimide film was obtained in the same manner as in Example 1 except that the reaction solution was obtained by stirring at 60 캜 for 12 hours under a nitrogen atmosphere instead of stirring for a time. The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. The results of measurement of the intrinsic viscosity [?] Of the polyamic acid obtained in the production process of the polyamic acid are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

(Comparative Example 5)

Instead of using bis [4- (3-aminophenoxy) phenyl] sulfone as an aromatic diamine in the production process of a polyamic acid,

(0.90 mmol, manufactured by Tokyo Kasei Kabushiki Kaisha; DATP) represented by the following formula (1), and further, in the production process of a film containing polyimide, A polyimide film was obtained in the same manner as in Example 1 except that the final heating temperature in the heating oven was changed from 350 占 폚 to 400 占 폚. The molecular structure of the compound forming the film obtained in the same manner as in Example 1 was identified, and as a result, it was confirmed to be polyimide. Further, with respect to the polyamic acid obtained in the production process of the polyamic acid, the measurement results of the intrinsic viscosity [?] Are shown in Table 1. Further, regarding the polyimide film, the evaluation results of properties (Tg and softening temperature obtained by the evaluation method of the above-mentioned characteristics) are shown in Table 1.

As is clear from the results shown in Table 1, all of the polyimide films of the present invention (Examples 1 to 8) had a retardation (Rth) in the thickness direction per 10 mu m of -100 to 100 nm, Was found to be sufficiently low (small value). In all of the polyimide films of the present invention (Examples 1 to 8), it was confirmed that the softening temperature was 265 DEG C or higher, the 5% weight reduction temperature was 463 DEG C or higher, and the heat resistance was sufficiently high. It was also confirmed that the polyimide films (Examples 1 to 8) of the present invention all had a total light transmittance of 87% or more and had sufficiently high transparency. From these results, it was found that the polyimide film (the polyimide film of the present invention) obtained in each example had high heat resistance and sufficient transparency, and the shortest value of the retardation (Rth) in the thickness direction was sufficiently small.

On the other hand, the polyimide film obtained in each Comparative Example had a value where the absolute value of the retardation (Rth) in the thickness direction per 10 탆 exceeded 100 nm (Comparative Example 1: -121 nm, Comparative Example 2: -136 nm, Comparative Example 3 : -793 nm, Comparative Example 4: -931 nm, Comparative Example 5: -1080 nm), and the absolute value of Rth was 100 nm or less.

INDUSTRIAL APPLICABILITY As described above, according to the present invention, a polyimide film which has sufficiently high heat resistance and transparency and can make the absolute value of the retardation (Rth) in the thickness direction sufficiently small, and an organic electroluminescent device using the same And the like.

Therefore, the polyimide film of the present invention has sufficiently high transparency and heat resistance, and the absolute value of the retardation (Rth) in the thickness direction is sufficiently small. Therefore, for example, a film for a flexible wiring board, A transparent conductive film for an organic thin film solar cell, a transparent conductive film for an organic thin film solar cell, a transparent conductive film for an organic thin film solar cell, a transparent conductive film for an organic thin film solar cell, A transparent conductive film for a dye-sensitized solar cell, a flexible gas barrier film, a film for a touch panel, a front film for a flexible display, a back film for a flexible display, a buffer coating film, a coverlay film and the like.

1: Organic EL device
11: Polyimide film
12: gas barrier layer
13: transparent electrode layer
14: Organic layer
15: metal electrode layer

Claims (4)

(1): &lt; EMI ID =

Wherein R ¹ , R ² and R ³ each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms and a fluorine atom, and R ¹⁰ is a group represented by the following general formula ( 101) to (108):

And n represents an integer of 0 to 12,
And a polyimide containing a repeating unit represented by the following formula
Wherein a retardation (Rth) in a thickness direction measured at a wavelength of 590 nm is -100 to 100 nm in terms of a thickness of 10 占 퐉. The method according to claim 1,
Wherein the retardation (Rth) in the thickness direction measured at the wavelength of 590 nm is -50 to 50 nm. An organic electroluminescent device comprising the polyimide film according to claim 1 or 2. An organic electroluminescence display comprising the polyimide film according to claim 1 or 2.

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