KR101912738B1 - High Transparency polyimide precursor resin composition having excellent Optical Characteristics and phase Retardation, method for manufacturing polyimide film using the same, and polyimide film thereof - Google Patents

Abstract

The present invention relates to a polyimide precursor resin composition which has a low thermal expansion coefficient, does not cause a whitening phenomenon during solution casting, has excellent high transparency and is excellent in an optical characteristic and a delay retardation characteristic, a manufacturing method of a polyimide film using the same, and a polyimide film manufactured thereby. The present invention can be usefully used in a flexible display substrate material and a semiconductor material. The polyimide precursor resin composition comprises a diamine component, an acid dianhydride compound and an organic solvent.

Description

TECHNICAL FIELD The present invention relates to a polyimide precursor resin composition having high transparency and excellent optical properties and phase retardation properties, a method for producing a polyimide film using the same, and a polyimide film produced by the method and a polyimide precursor composition having excellent optical characteristics and phase retardation for manufacturing polyimide film using the same, and polyimide film thereof}

The present invention relates to a polyimide precursor resin composition which has a low thermal expansion coefficient, does not cause whitening during solution casting, has excellent transparency and excellent optical and phase retardation properties, a method for producing a polyimide film using the same, The present invention relates to a polyimide film produced by the method of the present invention and can be used for a flexible display substrate material and a semiconductor material.

The substrate material of the flexible display which is attracting attention as the next generation display device should be light, unbreakable, warpable, and easy to process, so that there is no restriction on the form. Polymer materials which are not only lighter than glass substrates used as display substrate materials but also are not broken and are easy to manufacture and capable of producing thin film films are attracting attention as the most suitable materials for realizing flexible displays.

Flexible devices generally use organic light emitting diode (OLED) displays, and TFT processes with high process temperatures (300 to 500 DEG C) are used. Polymeric materials that withstand such high process temperatures are extremely limited. Accordingly, interest in polyimide (PI) resins having excellent heat resistance and dimensional stability as candidates for plastic substrates for transparent flexible displays has been increasing recently.

In order to apply the flexible display substrate, not only excellent heat resistance and dimensional stability but also excellent transparency, low refractive index and phase delay characteristics are required for securing the viewing angle of the display. However, typical polyimide colors are brown or yellow in color, mainly due to the intra-molecular and inter molecular interaction of the polyimide and the chaotropic complex (CTC) . This lowers the light transmittance of the polyimide thin film, raises the birefringence, and causes a narrow viewing angle problem. As related prior arts, Korean Patent Laid-Open Publication No. 2015-0046463 discloses a method of preparing a polyamic acid solution by using various acid dianhydrides and diamine compounds to improve colorless and transparent birefringence and retardation properties, A method for producing a film is provided.

On the other hand, an organic light emitting diode (OLED) display is manufactured by applying a resin to a glass substrate, thermally curing the film to form a film, and then removing the glass substrate from the glass substrate after various steps. The resin stability at room temperature is important when the resin is applied to the glass substrate during the manufacturing process. If the stability of the resin can not be ensured, a uniform film can not be formed after curing due to resin lump and white turbidity due to moisture, resulting in product defects.

Therefore, it is necessary to develop a colorless transparent polyimide resin which has resin stability at room temperature through a combination of an optimal monomer and an organic solvent for display material, has no color development, and has a low birefringence and excellent phase delay characteristics.

1: Korean Patent Publication No. 2015-0046463

Accordingly, in order to solve the above problems, the inventors of the present invention have found that, in preparing a polyimide film having high transparency and excellent optical and phase retardation properties, the composition of an aromatic diamine mixture containing a novel diamine compound, Solvent, and discovered a polyimide precursor resin composition having higher transparency, optical characteristics and phase retardation than conventional polyimide films, thereby completing the present invention.

Accordingly, it is an object of the present invention to provide a polyimide precursor resin composition which can be used as a flexible display substrate material having high transparency and excellent optical characteristics and phase delay characteristics.

It is another object of the present invention to provide a method for producing a polyimide resin film using the composition.

The present invention also provides a method for producing a film having a thickness of 10 to 15 탆, a refractive index of 0.01 or less, a retardation (Ro) in a plane direction of 1 nm or less, a retardation in a thickness direction (Rth) Or less, a transmittance of 85% or more, and a yellow index (YI) of 7 or less.

The present invention relates to a polyimide precursor resin composition comprising a diamine component, an acid dianhydride compound and an organic solvent, wherein the diamine component is 2,2-bis [4- (4-amino- Bis [4- (4-amino-2-trifluoromethylphenoxy) -phenyl] -1-phenyl-propane (BATP) 4,4'-bis (4-amino-2-trifluoromethylphenoxy) phenyl (BATPP) represented by the following Chemical Formula 3 and 4,4'-bis 4-amino-2-trifluoromethylphenoxy) biphenyl (BATPB), and a polyimide having high transparency and excellent optical characteristics and phase retardation characteristics. A precursor resin composition is provided.

Also, the present invention provides a method for producing a transparent polyimide resin film, wherein the polyamic acid solution prepared by using the composition is heat treated to be a film.

The present invention also relates to a method for producing a film having a thickness of 10 to 15 탆 and a thermal expansion coefficient of 25 ppm / 캜 or less at a glass transition temperature of 300 캜 or more and 100 to 300 캜, A transparent polyimide resin film having a transmittance of 85% or more and a yellow index (YI) at a wavelength of 550 nm of 7 or less.

In the case of the present invention, resin stability at room temperature, which does not cause whitening during solution casting, is better than that of conventional polyamic acid solution, and transparency, excellent mechanical properties, optical retardation, By providing heat resistance characteristics, it can be used for flexible display substrate material, semiconductor material, and the like.

The polyimide precursor resin composition of the present invention (hereinafter referred to as a " polyamic acid composition ") has an aromatic diamine component containing a novel specific amino compound and an organic solvent And a polyimide film excellent in optical characteristics and phase delay characteristics and having high transparency by optimizing the composition of the polyimide film and the amount of use thereof. The polyimide precursor composition according to the present invention, that is, the 'polyamic acid composition' refers to a composition used for producing a polyamic acid solution used for producing a polyimide film.

Specifically, the polyamic acid composition according to the present invention is a polyimide precursor resin composition comprising a diamine component, an acid dianhydride compound, and an organic solvent, wherein the diamine component is 2,2-bis [4- (4- (BATPPE), 1,1-bis [4-4-amino-2- trifluoromethylphenoxy] -phenyl] -1-phenyl-ethane (BATPPE) , 4,4'-bis (4-amino-2-trifluoromethylphenoxy) phenyl (BATPP), and 4,4'- (BATPB), which have excellent light transmittance and phase retardation characteristics. Each component will be described in detail as follows.

(A) a diamine component

The diamine component in the present invention can be obtained by reacting 2,2-bis [4- (4-amino-2-trifluoromethylphenoxy) -phenyl] propane (BATP) represented by the following formula (4-amino-2-trifluoromethylphenoxy) -phenyl] -1-phenyl-ethane (BATPPE), 4,4'- Bis (4-amino-2-trifluoromethylphenoxy) biphenyl (BATPP) represented by the following general formula (4) Contains at least one aromatic diamine selected.

[Chemical Formula 1]

(2)

(3)

[Chemical Formula 4]

In this case, the aromatic diamine compounds represented by the general formulas (1) to (4) preferably include 5 to 30 mol% based on the total amount of the diamine component. When the aromatic diamine compound represented by the general formulas (1) to (4) is less than 5 mol%, improvement of the birefringence and retardation characteristics is limited. When the aromatic diamine compound is more than 30 mol% .

The diamine component may include not only fluorinated aromatic diamine monomers such as TFMB but also non-fluorinated aromatic diamine monomers. Specifically, the aromatic diamine component may be at least one selected from the group consisting of 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl (TFMB), 4,4-oxydianiline Aniline (MDA), p-phenylenediamine (pPDA), m-phenylenediamine (mPDA), p-methylenedianiline (pMDA), m-methylenedianiline (mMDA), p-cyclohexanediamine (p-xylylene diamine (pXDA), m-xylenediamine (mXDA), m-cyclohexanediamine (mCHDA), 4,4'- diaminodiphenylsulfone (DDS), 2,2- (4-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane (BAFP) and 2,2-bis [4- ). ≪ / RTI >

(B) an acid dianhydride compound

The aromatic acid dianhydride compound of the present invention includes a fluorinated aromatic acid dianhydride, a non-fluorinated aromatic acid dianhydride compound, or a mixture thereof.

When the fluorinated aromatic dianhydride and the non-fluorinated aromatic acid dianhydride compound are mixed and used, the optical characteristics and heat resistance characteristics of the polyimide film can be simultaneously improved. The fluorine substituent of the fluorinated aromatic dianhydride can produce a polyimide film having excellent optical characteristics and a polyimide film having excellent heat resistance characteristics due to the rigid molecular structure of the aromatic acid dianhydride.

Specifically, the fluorinated aromatic acid dianhydride is an aromatic acid dianhydride to which a fluorine substituent is introduced, for example, 4,4 '- (hexafluoroisopropylidene) diphthalic anhydride (4,4' - (Hexafluoroisopropylidene) diphthalic (4,4'- (4,4'-hexafluoroisopropylidene diphenoxy) bis- (phthalic anhydride) (4,4'- (4,4'-hexafluoroisopropylidenediphenoxy) bis- (phthalic anhydride, 6-FDPDA) may be used.

Next, the non-fluorinated aromatic acid dianhydride is an aromatic acid dianhydride to which no fluorine substituent is introduced, such as pyromellitic dianhydride (PMDA), 3,3 ', 4,4'-biphenyltetracarboxylic acid 3,3'4,4'-biphenyltetracarboxylic acid dianhydride (BPDA), 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride (3,3', 4,4'-benzophenonetetracarboxylic acid dianhydride , BTDA), 4,4'-oxydiphthalic anhydride (ODPA), 2,2-bis [4-3,4-dicarboxyphenoxy] phenyl] propane anhydride (2,2- Bis [4- (3,4-dicarboxyphenoxy) phenyl] propane dianhydride, BPADA), 3,3 ', 4,4'-diphenylsulfone tetracarboxylic acid anhydride (3,3', 4,4'- at least one selected from the group consisting of tetracarboxylic dianhydride (DSDA), ethylene glycol bis (4-trimellitate anhydride) and ethylene glycol bis (4-trimellitate anhydride).

Preferably, the present invention is characterized in that when a compound represented by the above general formula (1) is contained as a diamine component, 4,4 '- (hexafluoroisopropylidene) diphthalic anhydride (6FDA), 4 (6-FDPDA), cyclobutane tetracarboxylic acid dihydrate (CBDA), 3,3 ', 4 (4,4'-hexafluoroisopropylidene diphenoxy) Biphenyl tetracarboxylic acid dihydrate (s-BPDA), bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic acid dihydrate (BTDA), 4 - (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid dihydrate (TDA), pyromellitic acid dihydrate ), Benzophenone tetracarboxylic acid dihydrate (BTDA), and oxydiphthalic dihydrate (ODPA).

(C) an organic solvent

The organic solvent in the present invention may be an organic solvent such as m-cresol, N-methyl-2-pyrrolidone (NMP), N, N-dimethylformamide (DMF), dimethylacetamide (DMAc), dimethylsulfoxide A polar solvent such as ethyl acetate (DEA), 3-methoxy-N, N-dimethylpropanamide (DMPA) or the like, a low boiling solvent such as tetrahydrofuran (THF), chloroform, or the like such as gamma-butyrolactone and GBL A low-absorbent solvent can be used.

Specifically, the organic solvent used in the present invention plays an important role in improving the whitening phenomenon. In order to improve the whitening phenomenon upon solution casting at room temperature, gamma-butyrolactone (GBL) and N-methyl- (NMP) or a mixture of gamma-butyrolactone (GBL) and 3-methoxy-N, N-dimethylpropanamide (DMPA) or a mixture of 3-methoxy-N, N-dimethylpropanamide It is preferable to use water.

In this case, the amount of the organic solvent to be used is 30 to 70 mol% of gamma-butyrolactone (GBL), 70 to 70 mol% of N-methyl-2-pyrrolidone (NMP) 30 mol% is preferably used. More preferably, 30 to 50 moles of N-methyl-2-pyrrolidone (NMP) or 3-methoxy-N, N-dimethylpropanamide (DMPA) is added to 50 to 70 mol% of gamma-butyrolactone %to be. Or gamma-butyrolactone (GBL) alone may be used.

(D) Reaction Catalyst

The present invention may further comprise a reaction catalyst other than the above components. The reaction catalyst of the present invention may further include at least one member selected from the group consisting of trimethylamine, xylene, pyridine and quinoline according to reactivity, . The polyamic acid composition may contain a small amount of additives such as a plasticizer, an antioxidant, a flame retardant, a dispersant, a viscosity modifier, and a leveling agent as necessary within a range not significantly impairing the objects and effects of the present invention.

In addition, the polyamic acid solution obtained by polymerization using the diamine component, the acid dianhydride compound, the organic solvent, and the reaction catalyst, which is the polyamic acid composition according to the present invention, has a solid content of 10 to 40% by weight based on the total weight of the polyamic acid solution, By weight and 10 to 25% by weight. When the solid content is less than 10% by weight, there is a limit to increase the thickness of the film in the production of the film. When the solid content is more than 40% by weight, the viscosity of the polyamic acid resin is limited.

Specifically, the polyamic acid solution is prepared by mixing 95 to 100 parts by mol of a diamine component and 100 to 105 parts by mol of an acid dianhydride compound under the condition of a solid content of 10 to 40 wt% 48 hours. The reaction temperature may vary depending on the monomers used.

Here, it is preferable to add an acid dianhydride compound in an amount of -5 to 5 mol% relative to the aromatic diamine component so as to reach a target viscosity, for the reason of proper viscosity control and storage stability.

The polyamic acid solution produced through this reaction preferably has a viscosity in the range of 1,000 to 10,000 cP. If the viscosity is less than 1,000 cP, there is a problem in obtaining an appropriate level of film thickness. If the viscosity is more than 10,000 cP, uniform coating and effective solvent removal are problematic.

In addition, the transparent polyimide film and the method for producing the transparent polyimide film of the present invention are as follows. The present invention provides a transparent polyimide film prepared by thermally modifying a polyamic acid solution prepared by the above-described polyamic acid composition. The polyamic acid solution according to the present invention has viscosity and is prepared by coating the glass substrate with a suitable method and then heat-treating the film. The coating method can be applied by any conventional method without limitation including spin coating, dip coating, solvent casting, slot die coating, spray coating, ), But the present invention is not limited thereto.

The polyamic acid composition of the present invention can be made into a polyimide film by heat treatment in a high temperature convection oven. At this time, the heat treatment is performed under a nitrogen atmosphere, and the heat treatment is performed at 100 to 450 ° C for 30 to 120 minutes. More preferably, the film is preferably obtained under the conditions of a temperature and a time of 100 占 폚 / 30min, 220 占 폚 / 30min, 350 占 폚 / 30min. This is because of the imidization that can maximize the removal and characterization of suitable solvents.

Since the transparent polyimide film of the present invention is produced using the above-mentioned polyamic acid composition, it exhibits high transparency and at the same time has a low thermal expansion coefficient.

The polyimide film of the present invention has a refractive index of 0.01 or less, a retardation in a plane direction (Ro) of 1.0 nm or less, a retardation in a thickness direction (Rth) of 100 nm or less, a haze of 1.0 Transmittance is 85% or more, preferably 88% or more, and Yellow Index (YI) is 7 or less, preferably 5 or less.

The polyimide film of the present invention can be used in various fields. In particular, the polyimide film of the present invention can be used for OLED displays, liquid crystal device displays, TFT substrates, flexible printed circuit boards, flexible OLED surface illuminated substrates, And can be provided as a substrate and a protective film for a flexible display such as a substrate material for electronic species.

Hereinafter, the present invention will be described in more detail with reference to examples. However, these examples are for illustrating the present invention, and the scope of the present invention is not limited thereto.

Comparative Example  One

As the composition shown in the following Table 1, 32.329 g (0.101 mole) of a diamine-based monomer TFMB was dissolved in 444.08 g of DMPA as an organic solvent and dissolved in a nitrogen atmosphere at room temperature for 30 minutes to 1 hour. Then, 45.333 g (0.0102 mole) of dianhydride monomer, 6FDA was added and stirred for 24 hours to prepare a polyamic acid solution (reaction temperature: 30 占 폚, so that the solid content was 15% by weight based on the total weight of the reaction solvent) (Brookfield DV2T, SC4-27). As a result, the viscosity was found to be 4,500 cP.

Example  One

As the composition shown in Table 1, 30.257 g (0.094 mole) of TFMB as a diamine monomer and 2.743 g (0.005 mole) of BATPP were dissolved in 440.08 g of DMPA as an organic solvent and dissolved in a nitrogen atmosphere at room temperature for 30 minutes to 1 hour. Thereafter, 44.661 g (0.100 mole) of dianhydride monomer, 6FDA was added and stirred for 24 hours to prepare a polyamic acid solution (reaction temperature: 30 ° C, where the solid content was maintained at 15 wt% ) Viscosity was measured to be 4,800 cP as measured by a viscometer (Brookfield DV2T, SC4-27).

Example  2

As the composition shown in Table 2, 28.215 g (0.088 mole) of TFMB as a diamine monomer and 5.400 g (0.010 mole) of BATPP were dissolved in 440.08 g of DMPA as an organic solvent and dissolved in a nitrogen atmosphere at room temperature for 30 minutes to 1 hour. Then, 44.047 g (0.099 mole) of dianhydride monomer (6FDA) was added and stirred for 24 hours to prepare a polyamic acid solution (reaction temperature: 30 ° C, at which time the solids content was maintained at 15 wt% The Brookfield DV2T, SC4-27, viscosity measurement device had a viscosity of 4,500 cP.

Example  3

20.713 g (0.065 mole) of diamine-based monomer TFMB and 15.292 g (0.028 mol) of BATPP were dissolved in 440.08 g of DMAP as an organic solvent and dissolved in a nitrogen atmosphere at room temperature for 30 minutes to 1 hour. Thereafter, 41.657 g (0.094 mole) of 6FDA as an imidazol-based monomer was added and stirred for 24 hours to prepare a polyamic acid solution (reaction temperature: 30 占 폚, where the solid content was maintained at 15 wt% ). Viscosity was measured to be 4,600 cP by Brookfield DV2T, SC4-27.

Example  4

As the composition shown in Table 2, 30.136 g (0.094 mole) of a diamine-based monomer TFMB and 3.043 g (0.005 mol) of BATPPE were dissolved in 440.08 g of an organic solvent DMPA and dissolved in a nitrogen atmosphere at room temperature for 30 minutes to 1 hour. Then 44.483 g (0.100 mole) of dianhydride monomer 6FDA was added and stirred for 24 hours to prepare a polyamic acid solution (reaction temperature: 30 ° C., at which time the solids content was maintained at 15 wt% based on the total weight of the reaction solvent) (Brookfield DV2T, SC4-27). As a result, the viscosity was 4,700 cP

Example  5

As the composition shown in Table 2, 28.009 g (0.087 mole) of TFMB and 5.970 g (0.010 mol) of BATPPE as a diamine monomer were dissolved in 440.08 g of an organic solvent DMPA and dissolved in a nitrogen atmosphere at room temperature for 30 minutes to 1 hour. Then 44.483 g (0.100 mole) of dianhydride monomer 6FDA was added and stirred for 24 hours to prepare a polyamic acid solution (reaction temperature: 30 ° C., at which time the solids content was maintained at 15 wt% based on the total weight of the reaction solvent) The Brookfield DV2T, SC4-27, viscosity measurement device, had a viscosity of 4,600 cP

Example  6

As the composition shown in Table 2, 20.270 g (0.063 mole) of TFMB as a diamine monomer and 16.665 g (0.027 mol) of BATPPE were dissolved in 440.08 g of an organic solvent DMPA and dissolved in a nitrogen atmosphere at room temperature for 30 minutes to 1 hour. Then, 40.727 g (0.092 mole) of dianhydride monomer 6FDA was added and stirred for 24 hours to prepare a polyamic acid solution (reaction temperature: 30 ° C, at which time the solids content was maintained at 15 wt% based on the total weight of the reaction solvent) The Brookfield DV2T, SC4-27, viscosity measurement device, had a viscosity of 4,600 cP

Example  7

As the composition shown in Table 2, 30.446 g (0.095 mole) of a diamine-based monomer TFMB and 2.165 g (0.005 mol) of BATPP were dissolved in 440.08 g of an organic solvent DMPA and dissolved in a nitrogen atmosphere at room temperature for 30 minutes to 1 hour. Then, 45.051 g (0.101 mole) of dianhydride monomer, 6FDA was added and stirred for 24 hours to prepare a polyamic acid solution (reaction temperature: 30 ° C, at which time the solids content was maintained at 15 wt% with respect to the total weight of the reaction solvent (Brookfield DV2T, SC4-27). As a result, the viscosity was 4,800 cP

Example  8

As the composition shown in Table 2, 21.626 g (0.068 mole) of TFMB as a diamine monomer and 12.520 g (0.029 mol) of BATPP were dissolved in 440.08 g of an organic solvent DMPA and dissolved in a nitrogen atmosphere at room temperature for 30 minutes to 1 hour. Then, 43.515 g (0.098 mole) of 6FDA as an imidazol-based monomer was added and stirred for 24 hours to prepare a polyamic acid solution (reaction temperature: 30 ° C, at which time the solids content was maintained at 15 wt% (Brookfield DV2T, SC4-27). As a result, the viscosity was 4,300 cP

Example  9

As the composition shown in Table 2, 30.330 g (0.095 mole) of TFMB as a diamine monomer and 2.539 g (0.005 mol) of BATPB were dissolved in 440.08 g of an organic solvent DMPA and dissolved in a nitrogen atmosphere at room temperature for 30 minutes to 1 hour. Then, 44.792 g (0.101 mole) of dianhydride monomer 6FDA was added and stirred for 24 hours to prepare a polyamic acid solution (reaction temperature: 30 ° C, at which time the solids content was maintained at 15 wt% with respect to the total weight of the reaction solvent) (Brookfield DV2T, SC4-27). As a result, the viscosity was 4,700 cP

Example  10

21.069 g (0.066 mole) of diamine-based monomer TFMB and 14.364 g (0.028 mol) of BATPB were dissolved in 440.08 g of an organic solvent DMPA and dissolved in a nitrogen atmosphere at room temperature for 30 minutes to 1 hour as a composition shown in Table 2 below. Then, 42.228 g (0.095 mole) of dianhydride monomer (6FDA) was added and stirred for 24 hours to prepare a polyamic acid solution (reaction temperature: 30 ° C, at which time the solids content was maintained at 15 wt% (Brookfield DV2T, SC4-27). As a result, the viscosity was 4,800 cP

Experimental Example : Measurement of physical properties

(1) Evaluation of cloudiness at room temperature

The polyamic acid solution prepared in Examples 1 to 10 and Comparative Example 1 was dropped on a glass plate, and a predetermined thickness (15 탆 after heat treatment when the solution thickness was 100 탆 based on a solid content of 15%) was raised using a spin coater, , And humidity of > 90% for 30 minutes. The level of cloudiness was assessed from 0 to 5 (0: no occurrence, 5: severe occurrence).

(2) Film production and property evaluation

The polyamic acid solution was coated on a glass plate using a spin coater and then heat treated in a high temperature convection oven. The heat treatment was conducted under a nitrogen atmosphere, and the final film was obtained under the conditions of 100 ° C./30 min., 220 ° C./30 min. And 350 ° C./30 min. The film thus obtained was measured for physical properties as described below, and the results are shown in Table 2 below.

(a) Transmittance

The transmittance was measured at 532 nm using a UV-Vis NIR Spectrophotometer (Shimadsu, UV-1800).

(b) birefringence and retardation

(TE value) - (TM value) was calculated as a birefringence value at 532 nm using TE (Transeverse Elictric) mode and Transverse Magnetic (TM) mode using a refractive index meter (Metricon, Prism Coupler 2010M) The retardation (R _o ) in the plane direction of 532 nm and the retardation (R _th ) in the thickness direction were measured using a phase difference measuring instrument (Otsuka, RETs-100).

(c) Yellowness Index (YI)

And measured using a color difference meter (LabScan XE).

(d) turbidity (haze)

And measured using a haze meter (TOYOSEIKI, HAZE-GARD).

Composition Example Comparative Example One 2 3 4 5 6 7 8 9 10 One Composition Acid dewatering 6FDA 100 100 100 100 100 100 100 100 100 100 100 Diamine TFMB 95 90 70 95 90 70 95 70 95 70 100 BATP 5 10 30 - - - - - - - - BATPPE - - - 5 10 30 - - - - - BATPP - - - - - - 5 30 - - - BATPB - - - - - - - - 5 30 - Organic solvent
(Unit: mol%) DMPA = 100 Property measurement Goal Value Example Comparative Example One 2 3 4 5 6 7 8 9 10 One Properties
Measure Viscosity
(cP, 23 < 0 > C) 1000
~ 7000 4800 4500 4600 4700 4600 4600 4800 4300 4700 4800 4500 Cloudiness level (room temperature, RH> 90%) 0 0 0 0 0 0 0 0 0 0 0 0 Thickness (㎛) 10 11 10 12 11 10 10 11 11 10 11 11 Transmittance
(%, @ 532 nm) > 88 90 91 91 88 88 89 90 88 89 89 91 Haze &Lt; 1.0 0.31 0.38 0.33 0.29 0.42 0.35 0.71 0.66 0.53 0.55 0.33 YI <10 5 4 4 6 6 5 4 6 7 9 4 Birefringence (@ 532 nm) <0.01 0.0093 0.0069 0.0033 0.0093 0.0075 0.0072 0.0093 0.0088 0.0081 0.0063 0.0101 Phase difference
(nm) R ₀ &Lt; 1.0 0.55 0.61 0.43 0.68 0.51 0.84 0.63 0.70 0.51 0.55 0.76 R _th <100 45 32 20 73 58 48 95 71 88 51 90 * 6FDA: 4,4 '- (hexafluoroisopropylidene) diphthalic anhydride (4,4' - (Hexafluoroisopropylidene) diphthalic anhydride)
* PMDA: pyromellitic dianhydride
TFMB: 2,2'-bis (trifluoromethyl) benzidine (2,2'-bis (trifluoromethyl)
BATP: 2,2-Bis [4- (4-amino-2-trifluoromethylphenoxy) -phenyl] propane)
BATPPE: 1,1-Bis [4- (4-amino-2-trifluoromethylphenoxy) -phenyl] trifluoromethylphenoxy) -phenyl] -1-phenyl-ethane
* BATPP: 4,4'-bis (4-amino-2-trifluoromethylphenoxy) phenyl 4,4'- Bis (4-amino-2-trifluoromethylphenoxy) biphenyl (4,4'-bis
DMPA: 3-methoxy-N, N-dimethyl propanamide.

As shown in Table 1, in the case of Examples 1 to 10 as compared with Comparative Example 1, it was confirmed that when the BATPP, BATPPE, BATP, and BATPB, which are new diamine monomers, are contained in a predetermined amount, . In addition, the transmittance, turbidity and yellowness required for the polyimide film are satisfied, and the whitening phenomenon does not occur.

Thus, the polyamic acid precursor resin solution prepared according to the present invention has a transmittance of 88% or more at a wavelength of 532 nm, a Yellow Index (YI) of 6 or less, a birefringence of 0.01 or less , And a phase difference (R _th ) in the plane direction of 100 or less.

Accordingly, the polyimide film produced according to the present invention satisfies excellent light transmittance and phase retardation characteristics, and can be used for OLED displays, liquid crystal display, TFT substrate, flexible printed circuit board, flexible OLED surface illuminated substrate, And can be widely applied to a substrate and a protective film for a flexible display such as a substrate material.

Claims (9)

A polyimide precursor resin composition comprising a diamine component, an acid dianhydride compound, and an organic solvent,
The diamine component may be selected from the group consisting of 2,2-bis [4- (4-amino-2-trifluoromethylphenoxy) -phenyl] propane (BATP) Bis (4-amino-2-trifluoromethylphenoxy) -phenyl] -1-phenyl-ethane (BATPPE) and 4,4'- (BATPB). The polyimide precursor resin composition according to claim 1, wherein the aromatic diamine is at least one compound selected from the group consisting of poly (vinylidene fluoride)

[Chemical Formula 1]

(2)

[Chemical Formula 4]

The polyimide precursor resin composition according to claim 1, wherein the aromatic diamine compound represented by the general formulas (1), (2) and (4) comprises 5 to 30 mol% based on the total amount of the diamine component.
The method of claim 1, wherein the diamine component is selected from the group consisting of 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl (TFMB), 4,4-oxydianiline -Methylene dianiline (MDA), p-phenylenediamine (pPDA), m-phenylenediamine (mPDA), p-methylene dianiline (pMDA), m- pCHDA), p-xylenediamine (pXDA), m-xylenediamine (mXDA), m-cyclohexanediamine (mCHDA), 4,4'- diaminodiphenylsulfone (DDS) (4-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane (BAFP), and 2,2-bis [4- Propane (BAPP). The polyimide precursor resin composition according to claim 1,
The method of claim 1 wherein the organic solvent is selected from the group consisting of gamma-butyrolactone (GBL) and N-methyl-2-pyrrolidone (NMP) , N-dimethylpropanamide (DMPA), or a mixture of 3-methoxy-N, N-dimethylpropanamide (DMPA) alone.
The organic solvent according to claim 1, wherein the organic solvent is at least one selected from the group consisting of N-methyl-2-pyrrolidone (NMP) or 3-methoxy-N, N-dimethylpropanamide DMPA) of 70 to 30 mol% based on the total weight of the polyimide precursor resin composition.
A process for producing a polyimide resin film, which comprises heat-treating a polyamic acid solution prepared by using the composition of any one of claims 1 to 5.
The polyamic acid solution according to claim 6, wherein the polyamic acid solution is prepared by mixing 95 to 100 parts by mol of a diamine component and 100 to 105 parts by mol of an acid dianhydride compound with an organic solvent content of 10 to 40 wt% A method for producing a polyimide resin film.
The method according to claim 6, wherein the polyamic acid solution is 1,000 to 10,000 cP.
A film produced by the method of claim 6 has a glass transition temperature of 300 ° C or higher, a thermal expansion coefficient of 25 ppm / ° C or lower in a range of 100 to 300 ° C, a transmittance at a wavelength of 550 nm of 85 % Or more, and a yellow index (YI) at a wavelength of 550 nm of 7 or less.