TW201444916A - Polyimide resin and polyimide film produced therefrom - Google Patents

Abstract

Disclosed herein is a polyimide resin including a silica filler surface-treated with a fluorine-containing compound, and a polyimide film formed using the polyimide resin. The polyimide resin has improved dispersibility and heat resistance because the surface of a silica filler is fluorinated.

Description

Polyimine resin and polyimine film made thereof

The present invention relates to a polyimine resin comprising a fluorinated cerium oxide filler and a polyimine film thereof.

Polyimide (PI) resin generally refers to a solution of a polyphthalic acid derivative by solution polymerization of an aromatic dianhydride with an aromatic diamine or an aromatic diisocyanate, followed by closed-loop dehydration at a high temperature. It is imidized to produce a heat resistant resin. In order to produce a polyimide resin, an aromatic dianhydride component such as pyromellitic dianhydride (PMDA) or biphenyltetracarboxylic dianhydride (BPDA) or the like, or an aromatic diamine component such as diaminodiphenyl may be used. Ether (ODA), p-phenylenediamine (p-PDA), m-phenylenediamine (m-PDA), bis(aniline)methane (MDA), bis(3-aminophenyl)hexafluoropropane (HFDA), and the like.

The polyimine resin is an insoluble super high heat resistant resin which has excellent properties such as oxidation resistance, high temperature resistance, radiation resistance, low temperature resistance and chemical resistance. Therefore, it is widely used in automotive materials, aerospace materials, and aerospace materials. In the field of electronic materials such as heat-resistant materials and insulating coating agents, insulating films, semiconductors, and electrode protective films for TFT-LCDs, they have recently been used for display materials such as optical fibers or liquid crystal alignment films, and have conductive fillers in the films, or on the surface. The use of a filler to form a transparent electrode film or the like is used.

Polyimine resin generally has a dark brown or yellow color. In order to make it transparent, a chain group (-O-, -SO ₂ -, -CO-, -CF ₃ CCF ₃ - etc.) may be introduced into the main chain or Large free volume branches to minimize the formation of intermolecular and intramolecular charge transfer complexes.

The heat resistance of such a transparent polyimide film is introduced into the above functions The base is weakened. This is because the color is lightened as the charge-transfer composite is reduced, but at the same time, the heat resistance is also weakened, and the heat resistance is weakened, which is difficult to use in the field of advanced materials such as displays or semiconductors which require higher process temperatures.

In addition, the filler can be used for various purposes in the film, such as increasing the mobility of the film production, or enhancing the deformation and heat resistance of the optical properties as needed, but it is difficult to uniformly disperse in the polyimide resin, so that practical application has not yet been achieved. .

SUMMARY OF THE INVENTION A primary object of the present invention is to provide a transparent polyimide film having a surface treated with a fluorinated cerium oxide filler. Another object of the present invention is to provide a display element substrate which improves heat resistance at the same time.

In order to achieve the above object, an embodiment of the present invention provides a polyimide resin comprising a cerium oxide filler surface-treated with a fluorine-containing compound.

In an embodiment of the invention, the content of the cerium oxide filler is from 0.01 to 0.1% by weight based on the total weight of the polyimide resin.

In one embodiment of the present invention, the fluorine-containing compound is selected from the group consisting of triethoxy fluorosilane, triethoxytrifluoromethylsilane, and tetrafluorotrifluoromethylsilane. 1,1,2,2-tetrahydroperfluorohexyltriethoxysilane, nonafluorohexyltriethoxysilane (triethoxy-3,3,4,4,5,5,6,6,6 -nonafluorohexylsilane), triethoxy[4-(trifluoromethyl)phenyl]silane, and heptafluorodecyltriethoxydecane (triethoxy (3,3) , 4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl)silane).

In an embodiment of the invention, the polyimine resin has a haze of less than 1.5%.

In one embodiment of the present invention, the film made of the polyimide resin has an optical transmittance of 87% or more at a thickness of 25 to 100 μm and a wavelength of 550 nm.

In an embodiment of the invention, the polyimine resin contains a repeating unit of a diamine-based monomer and a dianhydride-based monomer, and the dianhydride-based monomer contains a bicyclo[2.2.2]oct-7-ene- 2,3,5,6-tetracarboxylic acid dianhydride (Bicyclo [2.2.2] oct-7-ene-2, 3, 5, 6-tetracarboxylic acid dianhydride, hereinafter referred to as BTA).

In one embodiment of the invention, the BTA is present in an amount of less than 4 to 30 mole percent for all of the di-anhydride monomers.

In an embodiment of the invention, the dianhydride monomer further comprises one or more compounds selected from the group consisting of hexafluoro dianhydride (6FDA), 4-(2,5-dioxotetrahydrofuran-3 -yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride (TDA), pyromellitic dianhydride (PMDA), benzophenone tetracarboxylic dianhydride (BTDA), 3 , 3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), oxydiphthalic anhydride (ODPA), bis-(phthalic anhydride) dimethyl decane (SiDA), diphenyl sulphate Ether tetracarboxylic dianhydride (BDSDA), 3,3,4,4-diphenylphosphonium tetracarboxylic dianhydride (SO2DPA), cyclobutane tetracarboxylic dianhydride (CBDA) and bisphenol A diether dianhydride ( 6HBDA).

In one embodiment of the invention, the diamine family monomer is from 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane (bisaminophenoxyphenyl heaxafluoropropane, 4BDAF), bisaminophenyl hexa Group of bisaminophenyl hexafluoropropane (33-6F, 44-6F), bistrifluoroouopropane (TFDB) and bisaminohydroxyphenyl heaxafluoropropane (DBOH) One or more fluorine-substituted diamine-based monomers are selected.

In an embodiment of the invention, the polyimide resin further comprises an acid anhydride group monomer.

In one embodiment of the invention, the anhydride family is a single system of 4-phenylethynyl phthalic anhydride (4-PEPA).

In an embodiment of the invention, the content of 4-phenylethynylphthalic anhydride is less than 20 mol% relative to the total amount of the diamine monomer.

In another embodiment of the present invention, a polyimide film made of a polyimide resin and a substrate for a display element containing a polyimide film are provided.

As described above, the present invention can provide a transparent polyimide film comprising a surface-fluorinated filler. Meanwhile, the present invention can also provide a substrate for a display element comprising a polyimide film containing the above filler.

Unless otherwise defined, all technical and scientific terms used in the specification have the same meaning as those of those skilled in the art. The general nomenclature used in this specification employs well-known methods commonly used in the art.

Throughout the specification, when a component is "comprising" or "comprising" a component, it is meant to include other components, and not to exclude other components.

The present invention relates to a polyimide film comprising a cerium oxide filler having a surface treated with a fluorine compound.

In another aspect, the present invention relates to a polyimide film produced from a polyimide resin and a substrate for a display element comprising a polyimide film.

The invention will be further illustrated below.

Since the cerium oxide filler itself has strong cohesiveness, that is, evenly distributed on the polyimide resin by using ultrasonic waves or various kinds of grinders, re-agglomeration may occur. To this end, the present invention uses a fluorine-containing compound to surface-treat the ceria filler to increase the free volume of the filler surface, and to prevent the agglomeration of the filler by mutual repulsive force, thereby improving the mixing property of the filler with the polyimide resin. And dispersion. The cerium oxide filler surface-treated with a fluorine-containing compound is treated with an acid to form a hydroxyl group (-OH) on the surface thereof, and then subjected to sol-gel treatment with a fluorine-containing alkoxysilane to achieve surface fluorination. deal with. In order not to interfere with the polymer resin The bonding structure can also change its characteristics, and its content may be 0.01 to 0.1% by weight based on the total polyimine, but may exceed 0.1% by weight depending on the kind of the polyimide resin.

The type of the above-mentioned acid is not limited, and any acid which can form a hydroxyl group on the surface of the ceria filler, for example, nitric acid, sulfuric acid, hydrochloric acid, acetic acid or the like, is not particularly limited as long as it can sufficiently form a hydroxyl group.

Further, the fluorine-containing alkoxysilane may be derived from triethoxy fluorosilane, triethoxytrifluoromethylsilane, tetrafluorohydroperoxyhexyltriethoxysilane ( 1,1,2,2-tetrahydroperfluorohexyltriethoxysilane), hexafluorohexyltriethoxysilane (triethoxy-3,3,4,4,5,5,6,6,6-nonafluorohexylsilane), triethoxy [4- (triethoxy[4-(trifluoromethyl)phenyl]silane) and heptadecafluorodecyltrimethoxyethoxysilane (triethoxy(3,3,4,4,5,5,6, 6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl)silane), one or more selected from the group, the content of which may vary depending on the type of alkoxysilane containing fluorine, but from The weight ratio of the fluorine-containing alkoxydecane to the cerium oxide filler may be from 100:1 to 50, preferably from 5 to 25, in terms of content comparison effect or cost.

The particle size of the cerium oxide filler should be adjusted depending on the characteristics of the film to be modified and the type of the filler to be added. Although not particularly limited, the average particle diameter may be in the range of 0.001 to 50 μm, preferably 0.01 to 1 μm. In this case, the modification effect of the polyimide film is easily obtained, and the polyimide film can obtain good surface and mechanical properties.

The ruthenium imide resin containing the ruthenium dioxide filler has a haze of less than 1.5%. When a film having a thickness of 15 to 100 μm is produced, the optical transmittance at a wavelength of 550 nm is 87% or more. Better turbidity and light transmission can be obtained when the same amount of filler is surface treated.

In addition, the polyimine resin contains a repeating unit of a diamine-based monomer and a dianhydride-based monomer, and the dianhydride-based monomer may contain a bicyclo[2.2.2]oct-7-ene-2,3,5. 6-tetracarboxylic acid dianhydride (Bicyclo [2.2.2] oct-7-ene-2, 3, 5, 6-tetracarboxylic acid dianhydride, hereinafter referred to as BTA).

For the transparent polyimine resin, due to the monomer added to keep it transparent, In many cases, the high heat resistance peculiar to the original polyimine is diminished. In order to improve its heat resistance, a diamine monomer (p-PDA), 4,4'-diaminodiphenyl ether (4,4-ODA) used in the past in polythenimine is used. Or dianhydrides (biphenyltetracarboxylic dianhydride (BPDA), pyromellitic dianhydride (PMDA), etc., but there is a problem of little improvement.

In the present invention, in order to improve the above disadvantages, a monomer having a functional group capable of linking on a diamine group monomer and a dianhydride group monomer (bicyclo[2.2.2] oct-7-ene-2 is introduced. , 3,5,6-tetracarboxylic dianhydride), therefore, different from the polymerization method of the polyimine which has no linkage group, the chain group is introduced into the main chain, so that the heat resistance of the polyimide film can be improved. .

The content of the above bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride may be 4-30 mol% or less relative to the total di-anhydride monomer, if the content thereof is low At 4 mol%, the effect of physical properties such as heat resistance is not improved because the number of functional groups is small; if it is more than 30 mol%, the film is liable to be broken due to a decrease in molecular weight, and it is difficult to exhibit the characteristics of the film. In this case, it may be impossible to manufacture a polyimide film due to poor reactivity of BTA. In this case, in order to improve the lower reactivity of BTA, a more flexible diamine monomer may be added, and binary Amine monomers can be derived from 4,4'-bis(3-aminophenoxy)diphenylphosphonium (mBAPS), aminophenoxybenzene (APB) derivatives and 2,2-bis[4-(4- Aminophenoxy)phenyl]hexafluoropropane (4-BDAF) is selected from the group consisting of.

Meanwhile, the di-anhydride group monomer additionally used in the present invention may be selected from the group of the following compounds or any combination thereof, but is not limited thereto: hexafluoro dianhydride (6FDA), 4-(2,5-dioxo) Tetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride (TDA), pyromellitic dianhydride (PMDA), benzophenone tetracarboxylic dianhydride (BTDA) , 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), oxydiphthalic anhydride (ODPA), bis-(phthalic anhydride) dimethyl decane (SiDA), Diphenyl sulfide tetraacid dianhydride (BDSDA), 3,3,4,4-diphenylphosphonium tetracarboxylic acid dianhydride sulfonyldiphthalic anhydride (SO2DPA), cyclobutane tetracarboxylic dianhydride (CBDA) and bisphenol A Diether dianhydride (6HBDA) and bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BTA).

As the above dianhydride group monomer, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane (4BDAF), bisaminophenylhexafluoropropane (33-6F, 44-6F) can be used. One or more fluorine-substituted diamine-based monomers are selected from the group consisting of bis(trifluoromethyl)diaminobiphenyl (TFDB) and bisaminophenyl hexafluoropropane (DBOH).

The present invention uses a fluorine-based diamine monomer and a fluoro-dianhydride monomer to improve the compatibility with the cerium oxide filler surface-treated with the fluorine-containing compound, and thus the dispersibility between the filler and the resin can be improved.

In addition, in order to further improve heat resistance, the present invention adds an acid anhydride group monomer in a 1:1 molar ratio in a dianhydride group monomer and a diamine group monomer, and replaces a polyimine molecular chain end with an acid anhydride group monomer. The imidization is carried out after the polymerization.

The acid anhydride group monomer is 4-phenylethynyl phthalic anhydride (hereinafter referred to as 4-PEPA), and the ratio of the diamine monomer to the dianhydride monomer can be With a 1:1 molar ratio, the content of 4-PEPA for all diamine monomer groups should be less than 20 mol%, preferably in the range of 4-20 mol%. If the 4-PEPA content is less than 4 mol%, the effect is negligible; if it is higher than 20 mol%, the molecular weight of the original polyimine chain is too small, and there is a problem that the physical properties are lowered.

In the present invention, a polyimide film made of a polyimide resin can be produced by a usual method and comprises a cerium oxide filler surface-treated with a fluorine-containing compound.

The method for adding the cerium oxide filler surface-treated with the fluorine-containing compound is not particularly limited, for example, a poly-proline solution is added before and after the polymerization; after the polymerization of the poly-proline is completed, a high-speed mixer, a three-roller, and a rotary mixer are used ( Mixer) and the like method of mixing the filler; the dispersion containing the filler in the vegetation is mixed into the polyamic acid solution.

As a specific embodiment, the polyimide film of the present invention is produced by first dispersing a cerium oxide filler surface-treated with a fluorine-containing compound in the first solvent at the above content, and then pressing 1: The 0.9 to 1:1.0 molar ratio polymerizes the diamine-based monomer and the di-anhydride group to obtain poly-proline, and then imidizes the obtained poly-proline to produce a film.

The polymerization reaction conditions are not particularly limited, but the reaction temperature is preferably from -20 to 80 ° C and the reaction time is from 2 to 48 hours. At the same time, it is preferred to carry out the reaction in an inert gas such as argon or nitrogen.

The first solvent used for the polymerization of the monomer is not particularly limited as long as it can dissolve the poly-proline, for example, from m-cresol, methylpyrrolidone (NMP), dimethylformamide (DMF), Methylacetamide (DMAc), dimethyl hydrazine (DMSO), acetone, ammonia acetate More than one polar solvent is selected from diethyl malonate. Further, a low-boiling solution such as tetrahydrofuran (THF) or chloroform or a low-absorbent solvent such as γ-butyrolactone may be used.

The first solvent content is not particularly limited, but in order to obtain a suitable molecular weight and viscosity of the polyaminic acid solution, the weight of the first solvent relative to the entire polyaminic acid solution is preferably between 50 and 95%, more preferably 70. -90% between.

In order to consider thermal stability, the glass transition temperature of the polyimide resin produced by imidization of the polyaminic acid solution prepared as described above is preferably between 200 and 400 °C.

A method of producing a polyimide film from the above polyamic acid solution can be carried out by a conventional method. The polyamic acid solution is cast on a support for imidization to obtain a film.

The imidization method employed at this time is a method of thermal imidization, chemical imidization, or both. In the chemical imidization method, a representative anhydrous acid dehydrating agent such as acetic anhydride and a representative tertiary amine imidizing solvent such as isoquinoline, methylpyridine or pyridine are introduced into the polyamic acid solution. When the thermal imidization method or the thermal imidization and chemical imidization methods are used, the heating conditions of the polyaminic acid solution may vary depending on the type of the polyaminic acid solution and the thickness of the polyimide film.

Next, a description will be given of a production example in which a polyimide film is produced by a thermal imidization and a chemical imidization method. Putting a dehydrating agent and an imidizing solvent into the polyaminic acid solution, and casting on the support, heating at a temperature of 50-200 ° C, preferably 80-180 ° C, to activate the dehydrating agent and After the imidization solvent is partially hardened and dried, the gelatinous polyphthalic acid film is peeled off from the support plate, and then the gel film is fixed on the support, and then heated at a temperature of 100-400 ° C 5-400 In a minute, a polyimide film can be obtained. The gel film can be fixed by a pin frame or a clip type holder. The above support body may be a glass plate, an aluminum foil, a stainless steel belt, a stainless steel drum or the like.

In addition, the polyaminic acid solution prepared in the present invention can be produced by the following method: after imidization of the prepared polyaminic acid solution, the imidization solution is put into the second solvent, and precipitated. , filtering and drying to prepare a polyimine solid, and uniformly dispersing the filler on the first solvent by an ultrasonic disperser, dissolving the polyimine solid in the polyimine solution, and then performing a film forming step. A polyimide film was prepared from the polyimide solution.

As described above, when the polyaminic acid solution is imidized, a method of thermal imidization, chemical imidization, or both may be employed. Taking the thermal imidization and chemical imidization method as an example, the dehydrating agent and the imidizing solvent may be put into the polyamic acid solution of the vegetation, and then heated at a temperature of 20-180 ° C for 0.5-12 hours to carry out the imine. Chemical.

The first solvent may be a solvent used in the polymerization of the polyaminic acid solution. In order to prepare the polyimine solid, the second solvent is a solvent having a lower polarity than the first solvent, specifically, water, alcohol, and diethyl ether. Select one or more of the classes and ketones.

In this case, the second solvent content is not particularly limited, but the weight of the second solvent and the polyaminic acid solution is preferably between 5 and 20. Considering the boiling point of the second solvent, the prepared polyimine solids are subjected to filtration and drying conditions at a temperature of 50 to 120 ° C for 3 to 24 hours.

Thereafter, in the film forming step, the polyimine solution in which the polyimine solid is dissolved is cast on the support, and the temperature is gradually raised at a temperature of 40 to 400 ° C, and heated for 1 minute to 8 hours to produce a polyfluorene. Imine film.

The present invention can further add a heat treatment process to the polyimide film produced by the above method. The temperature of the additional heat treatment step is preferably between 100 and 500 ° C, and the heat treatment time is from 1 to 30 minutes. The residual volatile component of the film after the heat treatment should be less than 5%, preferably less than 3%.

The thickness of the obtained polyimide film is not particularly limited, and is preferably from 10 to 250 μm, more preferably from 25 to 150 μm.

In the present invention, a polyimide film having a thermal expansion coefficient of 40 ppm/° C. or less and a thickness of 15 to 100 μm is produced, and its optical transmittance at a wavelength of 550 nm is more than 80%. Since it is transparent and has improved heat resistance, it can be used in a wide range of fields such as a substrate for display elements.

The invention will be further illustrated by the following examples, but the scope of the invention is not limited to the following preparation examples and examples.

<Preparation Example 1>

A 500 ml round flask cyclone was connected, and 2 g of colloidal cerium oxide (average particle diameter: 10 nm) and 0.8 M of nitric acid (350 ml) were placed under nitrogen, and then heated and stirred at 80 ° C for 6 hours. Then, after washing the above mixture with ethanol, it was dried in a vacuum oven at a temperature of 60 ° C for 24 hours. Time. An acid-treated 1.5 g of cerium oxide, 350 ml of ethanol, and 0.182 g of triethoxyfluorosilane were placed in a 500 ml round flask circulation apparatus under a nitrogen atmosphere, and heated at 60 ° C for 12 hours to circulate. Stir. Then, after washing and drying, 1.515 g of a cerium oxide filler (average particle diameter: 20 nm) surface-treated with a fluorine-containing compound was obtained.

<Preparation Example 2>

A 500 ml round flask circulation device was connected, and 2 g of colloidal cerium oxide (Nippon Shokubai Co., Ltd., average particle diameter: 10 nm) and 0.8 M of nitric acid (350 ml) were placed under nitrogen, and then heated and stirred at 80 ° C for 6 hours. Then, the mixture was washed with ethanol and dried in a vacuum oven at a temperature of 60 ° C for 24 hours. An acid-treated 1.5 g of cerium oxide, 350 ml of ethanol, and 0.23 g of triethoxytrifluoromethylsilane were placed in a 500 ml round flask circulation apparatus under nitrogen, and heated at 60 ° C for 12 hours. The circulation is stirred. Then, after washing and drying, 1.72 g of a cerium oxide filler (average particle diameter: 25 nm) surface-treated with a fluorine-containing compound was obtained.

<Example 1>

0.116 g of the cerium oxide filler produced in Production Example 1 was dispersed in 580 g of dimethylacetamide by nitrogen gas in a 1 L reactor connected to a stirrer, a nitrogen injection device, a titration funnel, a temperature regulator, and a cooler. After DMAc), the reactor temperature was adjusted to 25 °C. After putting and dissolving 64.046 g (0.2 mol) of TFDB here, 71.08 g (0.16 mol) of 6FDA was added and stirred for 3 hours to completely dissolve 6FDA. At this time, the solution temperature was maintained at 25 °C. At the same time, 9.928 g (0.04 mol) of BTA was added thereto and stirred for 24 hours to prepare a polyamic acid solution having a solid content of 20% by weight.

0.34 g of Grubbs was placed in the prepared polyamic acid solution, and after heating at 50 ° C for 30 minutes, 31.64 g of pyridine and 40.8 g of acetic anhydride were further added, followed by stirring for 60 minutes. Then, the preparation solution was spread on a stainless steel plate and cast for 300 μm, and then dried by hot air at 80 ° C for 30 minutes or less, and then the temperature was raised to 120 ° C and dried for 30 minutes or less, and the film was peeled off from the stainless steel plate and fixed to the shelf with a pin. The fixed film shelf was placed in a hot air oven, slowly heated from 120 ° C to 300 ° C in 2 hours, and then slowly cooled, and then separated from the shelf to obtain a polyimide film. Finally, the obtained polyimide film was heat-treated at 300 ° C for 30 minutes.

<Example 2>

0.116 g of the cerium oxide filler produced in Production Example 2 was dispersed in 580 g of dimethylacetamide by nitrogen gas in a 1 L reactor connected to a stirrer, a nitrogen injection device, a titration funnel, a temperature regulator, and a cooler. After DMAc), the reactor temperature was adjusted to 25 °C. After putting and dissolving 64.046 g (0.2 mol) of TFDB here, 71.08 g (0.16 mol) of 6FDA was added and stirred for 3 hours to completely dissolve 6FDA. At this time, the solution temperature was maintained at 25 °C. At the same time, 9.928 g (0.04 mol) of BTA was added thereto and stirred for 24 hours to prepare a polyamic acid solution having a solid content of 20% by weight.

0.34 g of Grubbs was placed in the prepared polyamic acid solution, and after heating at 50 ° C for 30 minutes, 31.64 g of pyridine and 40.8 g of acetic anhydride were further added, followed by stirring for 60 minutes. Then, the preparation solution was spread on a stainless steel plate and cast for 300 μm, and then dried by hot air at 80 ° C for 30 minutes or less, and then the temperature was raised to 120 ° C and dried for 30 minutes or less, and the film was peeled off from the stainless steel plate and fixed to the shelf with a pin. The fixed film shelf was placed in a hot air oven, slowly heated from 120 ° C to 300 ° C in 2 hours, and then slowly cooled, and then separated from the shelf to obtain a polyimide film. Then, the obtained polyimide film was heat-treated at 300 ° C for 30 minutes.

<Example 3>

0.1165 g of the cerium oxide filler produced in Production Example 1 was dispersed in 580 g of dimethylacetamide by nitrogen gas in a 1 L reactor connected to a stirrer, a nitrogen injection device, a titration funnel, a temperature regulator, and a cooler. After DMAc), the reactor temperature was adjusted to 25 °C. After putting and dissolving 64.046 g (0.2 mol) of TFDB here, 66.64 g (0.15 mol) of 6FDA was added and stirred for 3 hours to completely dissolve 6FDA. At this time, the solution temperature was maintained at 25 °C. Meanwhile, 9.928 g (0.04 mol) of BTA and 4.965 g (0.02 mol) of 4-PEPA were added thereto, followed by stirring for 24 hours to prepare a polyamic acid solution having a solid content of 20% by weight.

0.34 g of Grubbs was placed in the prepared polyamic acid solution, and after heating at 50 ° C for 30 minutes, 31.64 g of pyridine and 40.8 g of acetic anhydride were further added, followed by stirring for 60 minutes. Then, the preparation solution was spread on a stainless steel plate and cast for 300 μm, and then dried by hot air at 80 ° C for 30 minutes or less, and then the temperature was raised to 120 ° C and dried for 30 minutes or less, and the film was peeled off from the stainless steel plate and fixed to the shelf with a pin. Put the fixed film shelf in the hot air oven within 2 hours The polyimine film was obtained by slowly heating from 120 ° C to 300 ° C and then slowly cooling, and then separating from the shelf. Then, the obtained polyimide film was heat-treated at 300 ° C for 30 minutes.

<Example 4>

0.1165 g of cerium oxide filler produced in Production Example 2 was dispersed in 580 g of dimethylacetamide by nitrogen gas in a 1 L reactor connected to a stirrer, a nitrogen injection device, a titration funnel, a temperature regulator, and a cooler. After DMAc), the reactor temperature was adjusted to 25 °C. After putting and dissolving 64.046 g (0.2 mol) of TFDB here, 66.64 g (0.15 mol) of 6FDA was added and stirred for 3 hours to completely dissolve 6FDA. At this time, the solution temperature was maintained at 25 °C. Meanwhile, 9.928 g (0.04 mol) of BTA and 4.965 g (0.02 mol) of 4-PEPA were added thereto, followed by stirring for 24 hours to prepare a polyamic acid solution having a solid content of 20% by weight.

0.34 g of Grubbs was placed in the prepared polyamic acid solution, and after heating at 50 ° C for 30 minutes, 31.64 g of pyridine and 40.8 g of acetic anhydride were further added, followed by stirring for 60 minutes. Then, the preparation solution was spread on a stainless steel plate and cast for 300 μm, and then dried by hot air at 80 ° C for 30 minutes or less, and then the temperature was raised to 120 ° C and dried for 30 minutes or less, and the film was peeled off from the stainless steel plate and fixed to the shelf with a pin. The fixed film shelf was placed in a hot air oven, slowly heated from 120 ° C to 300 ° C in 2 hours, and then slowly cooled, and then separated from the shelf to obtain a polyimide film. Then, the obtained polyimide film was heat-treated at 300 ° C for 30 minutes.

<Example 5>

The 0.108 cerium oxide filler produced in Production Example 1 was dispersed in 541 g of dimethylacetamide (DMAc) by nitrogen gas in a 1 L reactor connected to a stirrer, a nitrogen injection device, a titration funnel, a temperature regulator, and a cooler. After the above, the reactor temperature was adjusted to 25 °C. After putting and dissolving 64.046 g (0.2 mol) of TFDB here, 35.306 g (0.12 mol) of BPDA was added and stirred for 3 hours to completely dissolve BPDA. At this time, the solution temperature was maintained at 25 °C. Meanwhile, 31.08 g (0.07 mol) of 6FDA and 4.965 g (0.02 mol) of 4-PEPA were added thereto and stirred for 24 hours to prepare a polyamic acid solution having a solid content of 20% by weight.

0.34 g of Grubbs was placed in the prepared polyamic acid solution, and after heating at 50 ° C for 30 minutes, 31.64 g of pyridine and 40.8 g of acetic anhydride were further added, followed by stirring for 60 minutes. Then, the preparation solution is coated on a stainless steel plate and cast for 300 μm, and then hot air is used at 80 ° C. After drying for 30 minutes or less, the temperature was raised to 120 ° C and dried for 30 minutes or less, and the film was peeled off from the stainless steel plate and fixed to the shelf with a pin. The fixed film shelf was placed in a hot air oven, slowly heated from 120 ° C to 300 ° C in 2 hours, and then slowly cooled, and then separated from the shelf to obtain a polyimide film. Then, the obtained polyimide film was heat-treated at 300 ° C for 30 minutes.

<Comparative Example 1>

A polyimide film was produced in the same manner as in Example 1, except that a pure cerium oxide filler (Nippon Shokubai Co., Ltd., average particle diameter: 10 nm) which was not subjected to any treatment was added.

<Comparative Example 2>

A polyimide film was produced in the same manner as in Example 3, except that a pure cerium oxide filler (Nippon Shokubai Co., Ltd., average particle diameter: 10 nm) which was not subjected to any treatment was added.

<Comparative Example 3>

A polyimide film was produced in the same manner as in Example 5, except that a pure cerium oxide filler (Nippon Shokubai Co., Ltd., average particle diameter: 10 nm) which was not subjected to any treatment was added.

<Comparative Example 4>

In a 1 L reactor connected to a stirrer, a nitrogen injection device, a titration funnel, a temperature regulator, and a cooler, 611 g of dimethylacetamide (DMAc) was charged while passing nitrogen. The reactor temperature was adjusted to 25 ° C and the solution temperature of 25 ° C was maintained after dissolving 64.046 g (0.2 mol) of TFDB. After 88.85 g (0.2 mol) of 6FDA was added thereto and stirred for 24 hours, a polyglycine solution having a solid content of 20% by weight was prepared. The prepared solution was charged with 31.64 g of pyridine and 40.8 g of acetic anhydride, followed by stirring for 60 minutes. Thereafter, a polyimide film was produced in the same manner as in Example 1.

<Comparative Example 5>

In a 1 L reactor connected to a stirrer, a nitrogen injection device, a titration funnel, a temperature regulator, and a cooler, 540 g of dimethylacetamide (DMAc) was charged while passing nitrogen. Will react The temperature of the vessel was adjusted to 25 ° C, and after dissolving 64.046 g (0.2 mol) of TFDB, the temperature of the solution was maintained at 25 ° C. 35.306 g (0.12 mol) of BPDA was added here and stirred for 3 hours to completely dissolve BPDA. At this time, the solution temperature of 25 ° C was maintained. Then, 35.54 g (0.08 mol) of 6FDA was added to prepare a polyaminic acid solution having a solid content of 20% by weight. The prepared solution was charged with 31.64 g of pyridine and 40.8 g of acetic anhydride, followed by stirring for 60 minutes. Thereafter, a polyimide film was produced in the same manner as in Example 1.

<Comparative Example 6>

In a 1 L reactor connected to a stirrer, a nitrogen injection device, a titration funnel, a temperature regulator, and a cooler, 564 g of dimethylacetamide (DMAc) was filled with nitrogen gas. The reactor temperature was adjusted to 25 ° C and the solution temperature of 25 ° C was maintained after dissolving 64.046 g (0.2 mol) of TFDB. After adding 53.311 g (0.12 mol) of 6FDA, it was stirred for 3 hours to completely dissolve the 6FDA. At this time, the solution temperature of 25 ° C was maintained. Then, 19.85 g (0.04 mol) of BTAB was added and stirred for 24 hours to prepare a polyglycine solution having a solid content of 20% by weight. The prepared solution was charged with 0.509 g of Grubbs catalyst, and heated at 50 ° C for 30 minutes, and then 31.64 g of pyridine and 40.8 g of acetic anhydride were charged, followed by stirring for 60 minutes. Thereafter, a polyimide film was produced in the same manner as in Example 1.

<Comparative Example 7>

In a 1 L reactor connected to a stirrer, a nitrogen injection device, a titration funnel, a temperature regulator, and a cooler, 543.7 g of dimethylacetamide (DMAc) was charged while passing nitrogen. The reactor temperature was adjusted to 25 ° C and the solution temperature of 25 ° C was maintained after dissolving 64.046 g (0.2 mol) of TFDB. After adding 35.306 g (0.12 mol) of PBDA here, it was stirred for 3 hours to completely dissolve PBDA. At this time, the solution temperature of 25 ° C was maintained. Then, 26.655 g (0.06 mol) of 6FDA was added for stirring for 4 hours, and 9.93 g (0.04 mol) of 4-PEPA was further added to prepare a polyglycine solution having a solid content of 20% by weight. The prepared solution was charged with 31.64 g of pyridine and 40.8 g of acetic anhydride, followed by stirring for 60 minutes. Thereafter, a polyimide film was produced in the same manner as in Example 1.

<Comparative Example 8>

A polyimide film was produced in the same manner as in Example 1 except that the cerium oxide filler produced in Production Example 1 was not added.

<Comparative Example 9>

A polyimide film was produced in the same manner as in Example 5, except that the cerium oxide filler produced in Production Example 1 was not added.

<Feature evaluation method>

The physical properties were measured by the following methods, and the measurement results are shown in Table 1:

(1) Average light transmittance (%) measurement

The transmittance at a wavelength of 550 nm was measured with a UV spectrometer (Varian, Cary 100).

(2) Line thermal expansion coefficient (CTE) measurement

Using a thermomechanical analyzer (TA Instument, TMA Q400), the heating rate was 10 ° C / min., the test piece width was 4 mm × length 24, and the coefficient of thermal expansion of 50-250 ° C was measured.

(3) Turbidity measurement

The turbidity of the polyimide film was measured with a turbidimeter (Murakami Color Research Laboratory, HM-150).

(4) Thickness measurement

The thickness of the polyimide film was measured with an Anritsu (electronic micrometer).

As shown in Table 1, in Comparative Examples 1 and 2 and Comparative Example 1, the turbidity of Examples 1 and 2 was 1.1 and 1.0, respectively, under the same polyimine structure and the same filler content, and Comparative Example 1 The turbidity is quite high, reaching 2.5. It is presumed that this is because the filler contained in Comparative Example 1 was not well dispersed or the fillers were coagulated together during the film drying process. This phenomenon also occurs in the transmission rate.

Further, it can be understood from Comparative Example 1 and Comparative Examples 1 and 8, Example 5, and Comparative Examples 3 and 9, respectively, that the linear expansion coefficients (CTE) of Examples 1 and 5 are the same as those for the same polyimine composition. The comparative example is low. It can be seen that the linear expansion coefficient of the polyimine filler is lower than that of the organic material, and if the cerium oxide filler is uniformly dispersed on the resin as a matrix, the cerium oxide filler has an effect of reducing the thermal expansion of the resin.

Further, in Comparative Example 6, it was found that when the content of BTA was more than 30 mol% based on the total amount of the diamine-based monomer, a film could not be formed.

Simple variations or modifications of the present invention can be easily realized by those having ordinary knowledge in the field, and such variations and modifications can be considered as belonging to the scope of the present invention.

Claims (14)

A polyimine resin comprising a cerium oxide filler surface-treated with a fluorochemical. The polyimine resin according to claim 1, wherein the content of the cerium oxide filler is 0.01 to 0.1% by weight based on the total weight of the polyimide resin. The polyimine resin according to claim 1, wherein the fluorine-containing compound is selected from the group consisting of triethoxy fluorosilane, triethoxy ( Triethoxytrifluoromethylsilane, 1,1,2,2-tetrahydroperfluorohexyltriethoxysilane, nonafluorohexyltriethoxysilane (triethoxy-3,3,4, 4,5,5,6,6,6-nonafluorohexylsilane), triethoxy[4-(trifluoromethyl)phenyl]silane, and heptafluorodecyl Triethoxy (3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl) silane). The polyimine resin according to claim 1, wherein the polyimine resin has a haze of less than 1.5%. The polyimine resin according to claim 1, wherein the film made of the polyimide resin has an optical transmittance of 87% or more at a thickness of 25 to 100 μm and a wavelength of 550 nm. . The polyimine resin according to claim 1, wherein the polyimine resin contains a repeating unit of a diamine-based monomer and a dianhydride-based monomer, and the bis-anhydride monomer contains a double ring. [2.2.2] Oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic acid dianhydride, BTA ). The polyimine resin according to claim 6, wherein the bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride is relative to all of the di-anhydride groups. The monomer content is less than 4-30 mol%. The polyimine resin according to claim 6, wherein the bis-anhydride monomer further comprises one or more compounds selected from the group consisting of hexafluoro dianhydride (6FDA), 4-( 2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride (TDA), pyromellitic dianhydride (PMDA), benzophenone Tetracarboxylic dianhydride (BTDA), 3,3',4,4'-biphenyltetracarboxylic acid Diacid anhydride (BPDA), oxydiphthalic anhydride (ODPA), bis-(phthalic anhydride) dimethyl decane (SiDA), diphenyl sulfide tetraacid dianhydride (BDSDA), 3, 3, 4 , 4-diphenylphosphonium tetracarboxylic acid dianhydride sulfonyldiphthalic anhydride (SO2DPA), cyclobutane tetracarboxylic dianhydride (CBDA) and bisphenol A type diether dianhydride (6HBDA). The polyimine resin according to claim 6, wherein the diamine family system is 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane (bisaminophenoxyphenyl). Heaxafluoropropane, 4BDAF), bisaminophenyl hexafluoropropane (33-6F, 44-6F), bistrifluouopropane (TFDB) and bisaminophenyl hexafluoropropane One or more fluorine-substituted diamine-based monomers are selected from the group consisting of (bisaminohydroxyphenyl heaxafluoropropane, DBOH). The polyimine resin according to claim 6, wherein the polyimine resin further comprises an acid anhydride group monomer. The polyimine resin according to claim 10, wherein the anhydride group is a single system of 4-phenylethynyl phthalic anhydride (4-PEPA). The polyimine resin according to claim 11, wherein the content of the 4-phenylethynylphthalic anhydride relative to the total amount of the diamine monomer is less than 20 mol%. A polyimine film produced by the polyimine resin according to any one of claims 1 to 12. A substrate for a display element, comprising the polyimide film according to claim 13 of the patent application.