KR20200010089A - Polyimide-based resin powder and method for producing polyimide-based resin powder - Google Patents

Abstract

The present invention provides a polyimide-based resin powder having a high weight average molecular weight, good handling of the powder, and high solubility in a solvent, and a method for producing the powder. The amorphous polyimide-based resin powder has a specific surface area of 10 m^2/g or less, and a weight average molecular weight of 100,000 or more.

Description

Polyimide resin powder and manufacturing method of polyimide resin powder {POLYIMIDE-BASED RESIN POWDER AND METHOD FOR PRODUCING POLYIMIDE-BASED RESIN POWDER}

The present invention relates to a method for producing a polyimide resin powder and a polyimide resin powder.

At present, image display apparatuses, such as a liquid crystal display device and an organic electroluminescence display, are widely utilized not only for television but for various uses, such as a mobile telephone and a smart watch. With the expansion of such use, the image display apparatus (flexible display) which has a flexible characteristic is calculated | required.

An image display apparatus is comprised from structural members, such as a polarizing plate, a phase difference plate, and a front plate, in addition to display elements, such as a liquid crystal display element or an organic electroluminescence display element. In order to achieve a flexible display, all these components need to be flexible.

Glass is used as a front panel so far. Since glass is high in transparency and can express high hardness depending on the kind of glass, since it is very rigid and fragile, it is difficult to use it as a front plate material of a flexible display.

Therefore, utilization of a polymeric material is examined as a material which replaces glass. Since the front plate which consists of a polymeric material tends to express flexible characteristics, it can be expected to use for various uses. Although various things are mentioned as resin which has flexibility, For example, polyimide-type resin is mentioned.

When using a polyimide-based resin, for example, when manufacturing a polymer material such as a film, the polyimide-based resin is produced as a powder from the viewpoint of reducing the volume during transportation, and the powder is transported to a film forming place. And film forming is performed using the varnish of polyimide-type resin prepared using the said powder. As an example of such a powder of polyimide-based resin, Patent Document 1 discloses a polyimide powder having a specific specific surface area and solubility.

Japanese Patent No. 5833783

High bending resistance is required for a polymer material used as an optical member such as a flexible display. According to the examination of the present inventors, in order to achieve high bending resistance, it is conceivable to use, for example, a polyimide resin having a high weight average molecular weight. Here, although patent document 1 describes the manufacturing method of the polyimide powder by solid-state polymerization method, in the method described in patent document 1, the polyimide powder which has a sufficiently high weight average molecular weight cannot be manufactured, and such In the case of using the powder, it was found that the bending resistance of the final polymer material was not sufficient. Therefore, there is still a need for a polyimide resin powder having good handleability as a powder suitable for producing a polymer material containing a high molecular weight polyimide resin and having high solubility in a solvent when producing varnishes and the like. exist.

Accordingly, an object of the present invention is to provide a powder of polyimide resin having a high weight average molecular weight, good handleability of powder, and high solubility in a solvent, and a method for producing the powder.

MEANS TO SOLVE THE PROBLEM In order to solve the said subject, it focused on the molecular weight of polyimide-type resin, and the manufacturing conditions of polyimide-type resin powder, and earnestly examined. As a result, it was found that the above-mentioned problems were solved by an amorphous polyimide resin powder having a specific surface area of 10 m 2 / g or less and a weight average molecular weight of 100,000 or more, completing the present invention. It came to the following.

That is, this invention includes the following suitable aspects.

[1] An amorphous polyimide resin powder having a specific surface area of 10 m 2 / g or less and a weight average molecular weight of 100,000 or more.

[2] The polyimide resin powder according to [1], wherein the angle of repose is 45 ° or less.

[3] The polyimide resin powder according to the above [1] or [2], wherein the tap density is 0.3 to 0.6 g / cm 3.

[4] In the color difference measurement based on the L ^* a ^* b ^* colorimeter, the above-mentioned [1] to [3] satisfying L ^* ≥90, -10≤a ^* ≤10, and -10≤b ^* ≤10. The polyimide resin powder in any one of].

[5] A method for producing a polyimide resin powder according to any one of [1] to [4], wherein at least two kinds of a solution in which a polyimide resin is dissolved in a good solvent are used for the polyimide resin. Comprising contacting with a poor solvent of, comprising contacting the solution of the polyimide resin with the first poor solvent, and adding a second poor solvent to the solution obtained in the step; Manufacturing method.

[6] An optical film formed by using the polyimide resin powder according to any one of [1] to [4].

[7] A flexible display comprising the optical film as described in [6].

[8] The flexible display according to [7], further comprising a touch sensor.

[9] The flexible display according to [7] or [8], further comprising a polarizing plate.

According to the present invention, it is possible to provide a powder of polyimide resin having a high weight average molecular weight, good handleability of powder, and high solubility in a solvent.

EMBODIMENT OF THE INVENTION Below, embodiment of this invention is described in detail. In addition, the scope of the present invention is not limited to embodiment described here, A various change can be made in the range which does not deviate from the meaning of this invention.

The amorphous polyimide resin powder of the present invention (hereinafter also referred to as "polyimide resin powder of the present invention") has a specific surface area of 10 m 2 / g or less and a weight average molecular weight of 100,000 or more. It is qualitative polyimide resin powder.

The specific surface area of the polyimide resin powder of this invention is 10 m <2> / g or less. When the specific surface area of a polyimide resin powder exceeds 10 m <2> / g, the fine unevenness | corrugation of a particle surface increases, and the fluidity | liquidity of particle | grains falls. Therefore, particle | grains become easy to aggregate, and the handleability of a polyimide resin powder worsens. From the viewpoint of easy handling of the polyimide resin powder, the specific surface area of the polyimide resin powder is preferably 5 m 2 / g or less, more preferably 3 m 2 / g or less, and still more preferably 1 m 2. / g or less From the viewpoint of solubility, the specific surface area of the polyimide resin powder is preferably 0.01 m 2 / g or more, more preferably 0.05 m 2 / g or more, still more preferably 0.1 m 2 / g or more. In addition, the said specific surface area is a specific surface measured by the BET method, and can be measured by the method as described in an Example specifically. As a method of making the specific surface area of a polyimide-type resin powder into the said range, for example, the powder containing contacting the solution containing polyimide-type resin with at least 2 types of poor solvents with respect to polyimide-type resin A manufacturing method is mentioned. By using two kinds of poor solvents having different solubility in polyimide resins, in other words, two kinds of poor solvents having different precipitation properties for polyimide resins, the powder is firstly contacted with the first poor solvent. It is thought that the nucleus of is precipitated, and the nucleus is grown by the second poor solvent to form powder particles. By depositing powder in this way, it is easy to manufacture the powder which has a smooth surface with a specific surface area of 10 m <2> / g or less. In addition, this invention is not limited to the said mechanism at all, In addition, the manufacturing method of the polyimide resin powder of this invention is not limited at all.

The weight average molecular weight of the polyimide resin powder of this invention is 100,000 or more. When the weight average molecular weight of the polyimide resin in the polyimide resin powder is less than 100,000, the flex resistance of the polymer material produced using the polyimide resin powder is not sufficient. From the viewpoint of increasing the flex resistance in the polymer material, the weight average molecular weight of the polyimide resin powder is preferably 150,000 or more, more preferably 200,000 or more, further preferably 250,000 or more, particularly preferably 300,000. That's it. The weight average molecular weight of the polyimide resin powder is preferably 800,000 or less, more preferably 600,000 or less, even more preferably 500,000 or less, from the viewpoint of ease of production of varnish or film forming property when producing a polymer material. Especially preferably, it is 450,000 or less. The said weight average molecular weight is measured by the gel permeation chromatography (GPC) measurement. As measurement conditions, you may use the conditions described in an Example.

The polyimide resin powder of the present invention is an amorphous polyimide resin powder. When the polyimide resin is not amorphous, for example, the solubility at the time of dissolving the polyimide resin powder in a solvent worsens at the time of preparation of a varnish. In the present specification, whether the polyimide resin is amorphous can be determined by wide-angle X-ray diffraction measurement, and specifically, when a diffraction peak derived from crystalline is not detected in the wide-angle X-ray diffraction measurement, Such polyimide resin is amorphous. In addition, the measurement of wide-angle X-ray diffraction can be performed, for example on the measurement conditions described in an Example.

The angle of repose of the polyimide resin powder of the present invention is preferably 45 ° or less, more preferably 42 ° or less, still more preferably 40 ° or less, and generally 20 ° or more. When the angle of repose is below the upper limit, the fluidity of the powder is good. The angle of repose can be measured using a powder property evaluation device (for example, Powder Tester PT-X manufactured by Hosokawa Micron Co., Ltd.), and can be measured by the method described in Examples.

The tap density of the polyimide resin powder of the present invention is preferably 0.3 g / cm 3 or more, more preferably 0.33 g / cm 3 or more, and even more preferably 0.36 g / cm from the viewpoint of volumetric efficiency during storage and transportation. Cm 3 or more. In addition, since the polyimide resin powder becomes hard to be consolidated due to its own weight, the tap density is preferably 0.6 g / cm 3 or less, more preferably 0.55 g / cm 3 or less, further preferably 0.5 g / cm 3 or less. The measurement of a tap density can be measured by the method based on JISK7370: 2000, or the method described in an Example, for example. For measurement of the tap density, for example, a device such as Tap Denser (KYT-5000) manufactured by Seishin Corporation may be used.

Polyimide-based resin powder of the present invention, L ^* a ^* b ^* color difference measurement based on the color system: according to (JIS Z 8781-4 conforming to ^{2013), L * ≥90, -10≤a} * ≤10, and It is preferable to satisfy −10 ≦ b ^* ≦ 10. L ^* in the color difference measurement is preferably 90 or more, more preferably 93 or more, and even more preferably 95 or more from the viewpoint of easily increasing the transparency and visibility of the finally obtained polymer material. The upper limit of L ^* is not specifically limited, What is necessary is just 100 or less. A ^* in the said color difference measurement shows the index | index of a red group, From a viewpoint of being easy to improve visibility in the film etc. which are formed using polyimide-type resin powder, Preferably it is -10 or more and 10 or less, More preferably, Preferably it is -7 or more and 7 or less, More preferably, it is -5 or more and 5 or less. B ^* in the said chrominance measurement shows the index | index of a blue group, From a viewpoint of being easy to improve visibility in the film etc. which are formed using polyimide-type resin powder, Preferably it is -10 or more and 10 or less, More preferably, Preferably it is -5 or more and 10 or less, More preferably, it is -3 or more and 7 or less. The said color difference can be measured using a color difference meter, for example, can be measured by the method of describing in an Example.

Regarding the particle size distribution of the polyimide resin powder of the present invention, d ₅₀ is preferably 20 to 800 µm, more preferably 50 to 500 µm, further preferably from the viewpoint of the dissolution rate when dissolved in a solvent. Is 100-300 micrometers. Particle size distribution can be measured using a particle size analyzer, and can be measured by the method described in an Example, for example. From the viewpoint of scattering of the powder, d ₁₀ is preferably 5 to 500 µm, more preferably 30 to 300 µm, still more preferably 70 to 200 µm. In addition, from the viewpoint of suppressing the generation of lumps, d ₉₀ is preferably 50 to 1,000 µm, more preferably 100 to 700 µm, still more preferably 200 to 500 µm.

(Method for producing polyimide resin powder)

The polyimide resin powder of the present invention comprises contacting a solution in which a polyimide resin is dissolved in a good solvent with at least two poor solvents for the polyimide resin, and the solution of the polyimide resin It can manufacture by the manufacturing method including the process of contacting a 1st poor solvent, and the process of adding a 2nd poor solvent to the solution obtained by the said process. This invention also provides the said manufacturing method (Hereinafter, the said manufacturing method is also called "the manufacturing method of this invention.").

The manufacturing method of this invention includes contacting the solution which the polyimide-type resin melt | dissolved in the good solvent with at least 2 types of poor solvents with respect to the said polyimide-type resin, First, the solution and the agent of the said polyimide-type resin 1 step of contacting the poor solvent. The solution in which the polyimide resin is dissolved in the good solvent is a solution in which the polyimide resin is dissolved in the good solvent.

The solution may be a reaction solution obtained by polymerizing a monomer in a solvent (particularly a good solvent for a polyimide resin), or may be a solution obtained by dissolving the isolated polyimide resin in a good solvent. It is preferable to perform the polymerization reaction of a monomer in the good solvent mentioned later from a viewpoint of being easy to manufacture a polyimide-type resin solution, and to use the obtained reaction solution as a polyimide-type resin solution.

The good solvent contained in the polyimide-based resin solution is a solvent which is easy to dissolve the polyimide-based resin, and, for example, refers to a solvent having a solubility of 1% by mass or more at room temperature (20 to 30 ° C) with respect to the polyimide-based resin. . One type of solvent may be sufficient as the good solvent contained in a polyimide-type resin solution, and the mixture of 2 or more types of solvent may be sufficient as it. Examples of the good solvent include acetone, N, N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), γ-butyrolactone (GBL), and N, N-dimethylacetamide (DMAc). have. The solubility of the good solvent in the polyimide resin is preferably 3% by mass or more, more preferably 5% by mass or more from the viewpoint of volumetric efficiency. Although the upper limit of the solubility with respect to polyimide resin of a good solvent is not specifically limited, From a viewpoint that the usage-amount of a poor solvent can be reduced, Preferably it is 40 mass% or less, More preferably, it is 25 mass% or less.

The content of the good solvent in the polyimide-based resin solution is preferably 60 mass% or more, more preferably relative to the total amount of the polyimide-based resin solution, from the viewpoint of being easy to adjust to an operation-friendly viscosity. It is 75 mass% or more. The content of the good solvent in the polyimide resin solution is preferably 98% by mass or less, more preferably 95 to the total amount of the polyimide resin solution from the viewpoint of reducing the amount of poor solvent used. It is mass% or less.

The content of the polyimide resin in the polyimide resin solution is preferably 1% by mass or more and more preferably 3% by mass or more with respect to the total amount of the polyimide resin solution from the viewpoint of volumetric efficiency. The content of the polyimide resin in the polyimide resin solution is preferably 20% by mass or less with respect to the total amount of the polyimide resin solution from the viewpoint of being easy to adjust to a viscosity that is easy to handle in operation. More preferably, it is 10 mass% or less.

The manufacturing method of this invention includes contacting the polyimide-type resin solution which polyimide-type resin melt | dissolved in the good solvent with at least 2 types of poor solvents with respect to polyimide-type resin.

The poor solvent with respect to polyimide-type resin is a solvent which is hard to melt | dissolve polyimide-type resin, For example, it means the solvent whose solubility in room temperature (20-30 degreeC) with respect to polyimide-type resin is less than 1 mass%. The poor solvent may be one kind of solvent or a mixture of two or more kinds of solvents. As a poor solvent, methanol, 2-propanol, ethyl acetate, tetrahydrofuran, toluene, hexane, water is mentioned, for example.

Therefore, whether the solvent to be used is a good solvent or a poor solvent can be confirmed by the following method. When the polyimide resin is added to the solvent so as to be 1% by mass, the resin is dissolved in the solvent by heating and stirring if necessary, and the solution in the room temperature (20 to 30 ° C.) state becomes uniformly transparent. Is judged to be a good solvent, and it is judged to be a poor solvent when a dissolved residue is present or a resin once dissolved is precipitated. For example, in the present Example, the solvent was measured and put in the container, and it stirred, and the polyimide-type resin was put therein to be 1 mass%, and it stirred at room temperature (24 degreeC) for 3 hours. As a result, when a solution was uniformly transparent, it was a good solvent, and when a dissolved residue existed, it was judged as a poor solvent.

The manufacturing method of this invention includes contacting the polyimide-type resin solution which polyimide-type resin melt | dissolved in a good solvent, with at least 2 types of poor solvents with respect to the said polyimide-type resin. Here, contacting at least two kinds of poor solvents means contacting at least twice with different poor solvents. Below, at least two types of poor solvents are called a 1st poor solvent and a 2nd poor solvent, and it demonstrates. In addition to the first and second poor solvents, three or more types of poor solvents may be used. Moreover, although the contact with a 3rd poor solvent may be performed between the contact with a 1st poor solvent and a contact with a 2nd poor solvent, the poor solvent made to contact with a polyimide resin solution is a polyimide-type resin. It is preferable to make it contact in order that solubility to water may become low.

The first poor solvent and the second poor solvent are solvents which are difficult to dissolve the polyimide resin, and may be one kind of solvent or a mixture of two or more kinds of solvents, respectively. The first poor solvent and the second poor solvent may be one kind of different materials, one kind of one kind of substance, the other mixture of two or more kinds of substances, or both. The method may be a mixture of two or more substances. The first poor solvent and the second poor solvent may be a mixture of two or more kinds of substances different only in the mixing ratio of each other. From the viewpoint of easily precipitating the polyimide resin, the first poor solvent and the second poor solvent are preferably one kind of solvents having different solubility.

The manufacturing method of this invention contains at least the process of contacting the solution of polyimide-type resin, and a 1st poor solvent, and the process of adding a 2nd poor solvent to the solution obtained by the said process. Here, when a poor solvent is added to the solution of the polyimide-type resin in which the polyimide-type resin melt | dissolved in the good solvent, the solubility of the polyimide-type resin as a whole solvent will fall, and the polyimide-type resin which was not melt | dissolved will precipitate as powder. . When the rate of change of solubility due to the addition of the poor solvent is high, the rate at which the polyimide resin solidifies and precipitates is increased. If the precipitation rate is too fast, impurities such as catalysts and residual monomers easily enter the powder of the polyimide resin. Moreover, due to the height of the affinity between the polyimide resin and the good solvent, the good solvent may be contained in the precipitated polyimide resin, resulting in a rubbery mixture, and powder may not be obtained. According to the manufacturing method of this invention including the process of contacting the solution of a polyimide-type resin, and a 1st poor solvent, and the process of adding a 2nd poor solvent, the precipitation rate of a polyimide resin powder can be controlled. Since it can suppress that a solvent is contained in the polyimide resin powder which precipitates, a polyimide resin powder can be manufactured efficiently.

First, the process of making the solution of a polyimide resin and a 1st poor solvent contact is demonstrated. The method of bringing the solution of the polyimide resin into contact with the first poor solvent is not particularly limited as long as they contact. For example, the method of adding the first poor solvent to the polyimide resin solution, or the first bin The method of adding a polyimide resin solution to a solvent is mentioned. It is preferable to perform the process of contacting the solution of polyimide-type resin, and a 1st poor solvent from a viewpoint of easy to obtain powder by adding a 1st poor solvent to the solution of polyimide-type resin. Moreover, it is more preferable to add by dripping from a viewpoint of being easy to adjust an addition rate. In addition, in a polyimide-type resin solution, as long as at least one part of polyimide-type resin is melt | dissolved, some polyimide-type resin may be precipitated as powder and all the polyimide-type resin may melt | dissolve.

Next, the manufacturing method of this invention includes the process of adding a 2nd poor solvent to the solution (henceforth a "polyimide resin solution after contact with a 1st poor solvent") obtained at said process. . By adding the second poor solvent, the polyimide resin can be precipitated. It is preferable that the solubility with respect to the polyimide resin of a 2nd poor solvent is lower than the solubility with respect to polyimide resin of a 1st poor solvent from a viewpoint of making it easy to precipitate a polyimide resin by adding a 2nd poor solvent. .

It is preferable that a 1st poor solvent is a solvent which has a C1-C4 alcohol as a main component from a viewpoint of making it easy to precipitate a polyimide-type resin in the process of adding a following 2nd poor solvent. In addition, in this specification, making it a main component means that it occupies 70 mass% or more. The proportion of the alcohol having 1 to 4 carbon atoms in the first poor solvent is preferably 70% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more.

It is preferable that a 2nd poor solvent is a solvent which has water as a main component from a viewpoint of making it easy to precipitate a polyimide-type resin. The proportion of water in the second poor solvent is preferably 70% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more.

In the step of adding the second poor solvent to the polyimide resin solution after contact with the first poor solvent to precipitate the polyimide resin, the addition rate of the second poor solvent (kg / min), the first poor solvent and The amount (kg) of the resin in the polyimide resin solution after contact is

[Equation 1]

It is desirable to satisfy. By setting the addition rate of the second poor solvent relative to the amount of resin to the above value, the rate at which the polyimide resin is precipitated can be controlled, and it is easy to prevent the inclusion of a good solvent when the resin is precipitated. As a result, the particles are in close contact with each other to prevent agglomeration and powder is easily obtained. The value calculated by the above formula is preferably 0.8 or less, more preferably 0.5 or less, still more preferably 0.3 or less, particularly preferably 0.2 from the viewpoint of being easy to precipitate as powder while preventing the inclusion of a good solvent. It is as follows. Although the lower limit of the value computed by the said formula is not specifically limited, From a viewpoint of the manufacturing efficiency of a polyimide resin powder, it is about 0.01 or more normally. In addition, the quantity of resin in the polyimide-type resin solution after contact with the 1st poor solvent in the said formula is the time of resin precipitation in a 2nd poor solvent, the filtration process of the polyimide-type resin composition mentioned later, and a polyimide resin composition When there is no loss in the drying process, it is equivalent to the quantity of the polyimide resin powder obtained by drying the polyimide resin composition mentioned later. Usually, since the amount of resin in the polyimide-based resin solution after contact with the first poor solvent is the amount of polyimide-based resin powder after drying, whether the above formula is satisfied or not is polyimide after contact with the first poor solvent. It can also confirm by substituting and calculating the quantity of resin in system resin solution by the quantity of the polyimide resin powder after drying.

The method of adding the second poor solvent is not particularly limited with respect to the step of adding the second poor solvent to the solution of the polyimide resin obtained in the step of contacting with the first poor solvent. It is more preferable to add by dripping from a viewpoint that it is easy to adjust an addition rate and to suppress local concentration rise of a poor solvent easily. Regarding the second poor solvent added to the solution of the polyimide-based resin, the addition method is different depending on the addition method, but a portion having a high concentration of the poor solvent is formed locally immediately after the addition, and then spreads to the entire solution of the polyimide-based resin. . If the concentration of the second poor solvent is too high locally, the polyimide resin powder is rapidly precipitated locally, and impurities are easily mixed into the polyimide resin powder, or the solidified polyimide resin is used as a solvent. It may become difficult to obtain powder by including it. Therefore, it is preferable to select an addition method and an addition rate so that local precipitation does not occur as much as possible from a viewpoint of being easy to precipitate a polyimide resin powder efficiently and with high precision.

As a method of adding the second poor solvent to the solution containing the polyimide resin, a method capable of suppressing the local concentration rise of the second poor solvent from the viewpoint of suppressing the precipitation of the local polyimide resin powder. It is preferable and the method which can speed up an addition speed is preferable from a viewpoint of being easy to raise the manufacturing efficiency of a polyimide resin powder. In view of this, as a preferable method of adding the second poor solvent to the solution containing the polyimide resin, the second poor solvent is divided into lines using, for example, a nozzle having a plurality of nozzles or a plurality of branches. Adding by using a shower nozzle, adding by dipping a second poor solvent outlet in a solution containing a polyimide resin, attaching a dispersion plate to the end of the nozzle, and the like. Can be mentioned.

The manufacturing method of this invention filters the mixture obtained after the said process other than the process of contacting the solution of a polyimide-type resin, and a 1st poor solvent, and the process of adding a 2nd poor solvent to the solution obtained at the said process, You may further include the process of obtaining a polyimide-type resin composition. In addition, the polyimide resin composition obtained by filtration is a composition also called a wet cake, and is an intermediate for obtaining polyimide resin powder. The polyimide resin powder contains a polyimide resin powder, a good solvent and / or a poor solvent, and a polyimide resin powder is obtained by drying the polyimide resin composition.

Filtration method is not specifically limited about the process of filtering the obtained mixture and obtaining a polyimide-type resin composition, The method of separating by gravity, the method of separating by centrifugal force, and the pressurization through the filter from which the precipitate and solvent permeability differ. The separation method can be mentioned. Although the content of the poor solvent in the polyimide-based resin composition thus obtained varies depending on the filtration method, it is generally 5% by mass or more, more preferably based on the total mass of the polyimide-based resin composition. 10 mass% or more, More preferably, it is 20 mass% or more. The upper limit of the content of the poor solvent is preferably 70% by mass or less, more preferably 50% by mass with respect to the total mass of the polyimide resin composition from the viewpoint of being easy to manufacture the polyimide resin powder by drying. It is as follows. Moreover, content of the good solvent in a polyimide-type resin composition becomes like this. Preferably it is 1 mass% or less, More preferably, it is 0.3 mass% or less. The lower limit of the content of the good solvent is not particularly limited, and the smaller one is preferable. This invention also provides the said polyimide-type resin composition which is an intermediate in the manufacturing method of this invention. The polyimide resin powder of this invention can be manufactured by drying the polyimide resin composition of this invention and removing a solvent.

The manufacturing method of this invention may further include the process of drying a polyimide resin composition and obtaining a polyimide resin powder after the process of filtering the obtained mixture and obtaining a polyimide resin composition. Drying conditions are not specifically limited as long as the solvent in a polyimide resin composition is removed. For example, you may carry out by the method of heating at the temperature of 50-250 degreeC for 1 to 48 hours under reduced pressure or atmospheric pressure conditions.

(Polyimide Resin)

The polyimide resin powder of the present invention is a polyimide resin, polyamideimide resin or polyamic acid resin. The polyimide resin powder may be a powder containing one kind of polyimide resin, or may be a powder containing two or more kinds of polyimide resins. The polyimide resin is preferably a polyimide resin, a polyamideimide resin, and more preferably a polyamideimide resin from the viewpoint of film forming properties.

In one embodiment of the present invention, the polyimide resin is a polyimide resin having a structural unit represented by formula (1), or is represented by a structural unit represented by formula (1) and formula (2) It is preferable that it is a polyamideimide resin which has a structural unit. The polyimide resin is more preferably a polyamideimide resin having a structural unit represented by the formula (1) and a structural unit represented by the formula (2) from the viewpoint of transparency and flexibility. Although Formula (1) and Formula (2) are demonstrated below, description about Formula (1) relates to both a polyimide resin and a polyamide-imide resin, and the description about Formula (2) is a poly It relates to an amideimide resin.

[Formula 1]

The polyimide resin is a polyimide resin having a structural unit represented by the formula (1) or a polyamideimide resin having a structural unit represented by the formula (1) and a structural unit represented by the formula (2) In one aspect of the present invention, Y in Formula (1) each independently represents a tetravalent organic group, and preferably a tetravalent organic group having 4 to 40 carbon atoms. The said organic group is the organic group in which the hydrogen atom in the organic group may be substituted by the hydrocarbon group or the fluorine-substituted hydrocarbon group, In that case, carbon number of a hydrocarbon group and a fluorine-substituted hydrocarbon group becomes like this. Preferably it is 1-8. The said polyimide resin which is one Embodiment of this invention may contain several types of Y, and several types of Y may mutually be same or different. As Y, formula (20), formula (21), formula (22), formula (23), formula (24), formula (25), formula (26), formula (27), formula (28) or formula (29) Group represented by; Groups in which the hydrogen atoms in the groups represented by those formulas (20) to (29) are substituted by a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; And a tetravalent hydrocarbon group having 6 or less carbon atoms is exemplified.

[Formula 2]

[In Formula (20)-(29),

* Represents a bonding hand,

W ¹ is a single bond, -O-, -CH _2- , -CH ₂ -CH _2- , -CH (CH ₃ )-, -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -,- Ar-, -SO _2- , -CO-, -O-Ar-O-, -Ar-O-Ar-, -Ar-CH ₂ -Ar-, -Ar-C (CH ₃ ) ₂ -Ar- or -Ar-SO ₂ -Ar-. Ar represents a C6-C20 arylene group in which a hydrogen atom may be substituted by the fluorine atom, and a phenylene group is mentioned as a specific example.]

With formula (20), formula (21), formula (22), formula (23), formula (24), formula (25), formula (26), formula (27), formula (28) and formula (29) Among the groups represented, the group represented by the formula (26), the formula (28) or the formula (29) is preferable from the viewpoint of the surface hardness and the flexibility of the optical member comprising the polyimide resin, and the formula (26) The group represented by is more preferable. In addition, from the viewpoint of surface hardness and flexibility of the optical member including the polyimide-based resin, W ¹ is each independently, preferably a single bond, -O-, -CH _2- , -CH ₂ -CH _2- , -CH (CH ₃ )-, -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- , more preferably a single bond, -O-, -CH _2- , -CH (CH ₃ )-, -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- , more preferably a single bond, -O-, -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- , especially preferably a single bond, -O- or -C (CF _{3) 2} -, most preferably a single bond or -C (CF _{3) 2} - a.

In the said aspect, it is preferable that at least one part of some Y in Formula (1) is a structural unit represented by Formula (5). If at least one part of the some Y in Formula (1) is group represented by Formula (5), the optical member containing the said polyimide resin expresses high transparency, and originates in a high flexible frame | skeleton, The solubility to the solvent of the said polyimide resin can be improved, the viscosity of the varnish containing a polyimide resin can be suppressed low, and the process of an optical member can be made easy.

[Formula 3]

[In Formula (5), R <^18> -R <^25> respectively independently represents a hydrogen atom, a C1-C6 alkyl group, or a C6-C12 aryl group, and the hydrogen atom contained in R <^18> -R <^25> respectively Independently, they may be substituted with halogen atoms,

* Represents a bonding hand.]

In Formula (5), R <^18> , R <^19> , R <^20> , R <^21> , R <^22> , R <^23> , R <^24> and R <^25> are respectively independently a hydrogen atom, a C1-C6 alkyl group, or C6-C12 Aryl group of the compound, preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. Here, the hydrogen atoms contained in R ¹⁸ to R ²⁵ may be each independently substituted with a halogen atom. R ¹⁸ to R ²⁵ are each independently, from the viewpoint of surface hardness and flexibility of the optical member comprising the polyimide resin, more preferably a hydrogen atom, a methyl group, a fluoro group, a chloro group or a trifluoro It is a methyl group, Especially preferably, it is a hydrogen atom or a trifluoromethyl group.

In a suitable embodiment of the present invention, the structural unit represented by the formula (5) is a group represented by the formula (5 '), that is, at least a part of the plurality of Y is the structure represented by the formula (5'). Unit. In this case, the optical member containing the said polyimide resin can have high transparency.

[Formula 4]

[In formula (5 '), * represents a bond.]

In a suitable embodiment of the invention, preferably at least 50 mol%, more preferably at least 60 mol%, even more preferably at least 70 mol% of Y in the polyimide resin is formula (5), in particular It is represented by Formula (5 '). When Y in the said range in the said polyimide-type resin is represented by Formula (5), especially Formula (5 '), the optical member containing the said polyimide-type resin can have high transparency, and also fluorine The frame | skeleton containing an element improves the solubility to the solvent of the said polyimide resin, can suppress the viscosity of the varnish containing a polyimide resin low, and it is easy to manufacture an optical member. Moreover, Preferably, 100 mol% or less of Y in the said polyimide resin is represented by Formula (5), especially Formula (5 '). Y in the said polyimide-type resin may be Formula (5), especially Formula (5 '). The content of the constituent unit represented by formula (5) of the Y in the polyimide-based resin is, for example, may be calculated from the number, and the raw material or doipbi be measured by using a ¹ H-NMR.

In one aspect of the present invention, wherein the polyimide resin is a polyamideimide resin having a structural unit represented by the formula (1) and a structural unit represented by the formula (2), Z in the formula (2) is each independently And a divalent organic group. In one embodiment of the present invention, the polyamide-imide resin may include a plurality of types of Z, and the plurality of types of Z may be the same as or different from each other. The said divalent organic group, Preferably it shows a C4-C40 divalent organic group. The said organic group may be substituted by the hydrocarbon group or the fluorine-substituted hydrocarbon group, and in that case, carbon number of a hydrocarbon group and a fluorine-substituted hydrocarbon group becomes like this. Preferably it is 1-8. Examples of the organic group of Z include formula (20), formula (21), formula (22), formula (23), formula (24), formula (25), formula (26), formula (27), formula (28), or Among the bonds of the group represented by the formula (29), groups in which two adjacent groups are substituted with a hydrogen atom and a divalent chain hydrocarbon group having 6 or less carbon atoms are exemplified. From the viewpoint of improving the optical properties of the optical member, for example, reducing the yellowness, the formula (20), formula (21), formula (22), formula (23), formula (24), and formula (25) ), A group represented by a group in which two non-adjacent groups are substituted with a hydrogen atom among the bonds of the group represented by formula (26) or formula (27) is preferable.

In a suitable embodiment of the present invention, at least a part of Z is a structural unit represented by the formula (3) in view of the fact that the optical member can express excellent optical properties in addition to high bending resistance and high surface hardness. It is preferable.

[Formula 5]

[In formula (3), R <^1> , R <^2> , R <^3> , R <^4> , R <^5> , R <^6> , R <^7> and R <^8> respectively independently represent a hydrogen atom, a C1-C6 alkyl group, or C6-C12 Represents an aryl group, and the hydrogen atoms contained in R ¹ to R ⁸ may be each independently substituted with a halogen atom,

A is a single bond, -O-, -CH _2- , -CH ₂ -CH _2- , -CH (CH ₃ )-, -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -SO _2- , -S-, -CO- or -N (R ⁹ )-is represented, R ⁹ represents a hydrocarbon group having 1 to 12 carbon atoms which may be substituted with a hydrogen atom or a halogen atom,

m is an integer of 0 to 4,

* Represents a bonding hand.]

In Formula (3), m is preferably an integer in the range of 0-4, and when m is in this range, it will be easy to raise the elasticity modulus and flexibility of the optical member containing the said polyimide-type resin. In formula (3), m is preferably an integer in the range of 0 to 3, more preferably an integer in the range of 0 to 2, still more preferably 0 or 1, and m is within this range. The bending resistance and elastic modulus of the optical laminate are good, and the availability of the raw material is relatively good. Moreover, Z may contain 1 type, or 2 or more types of structural units represented by Formula (3), Especially from a viewpoint of the improvement of the elasticity modulus, bending resistance, and yellowness (YI value) of an optical laminated body, Two or more types of structural units from which the value of m differs, Preferably two types of structural units from which the value of m differs may be included. In that case, it is preferable that m contains both the structural units of 0 and 1 from a viewpoint that an optical laminated body is easy to express high elastic modulus, bending resistance, and low yellowness (YI value).

In the formula (3), A is, each independently, a single _{bond, -O-, -CH 2 -, -CH} 2 -CH 2 -, -CH (CH 3) -, -C (CH 3) 2 - , -C (CF ₃ ) _2- , -SO _2- , -S-, -CO- or -N (R ⁹ )-, and from the viewpoint of the flexibility of the optical member comprising the polyimide-based resin, Preferably -O- or -S- is represented, More preferably, -O- is represented. R ¹ to R ⁸ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms. Examples of the alkyl group having 1 to 6 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group and 2-methyl-butyl Group, 3-methylbutyl group, 2-ethyl-propyl group, n-hexyl group, etc. are mentioned. Moreover, as a C6-C12 aryl group, a phenyl group, a tolyl group, a xylyl group, a naphthyl group, a biphenyl group etc. are mentioned, for example. From the viewpoint of flexibility and surface hardness of the optical member including the polyimide resin, R ¹ to R ⁸ each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and more preferably A hydrogen atom or a C1-C3 alkyl group is shown, More preferably, a hydrogen atom is represented. Here, the hydrogen atoms contained in R ¹ to R ⁸ may be each independently substituted with a halogen atom. R <^9> represents the C1-C12 hydrocarbon group which may be substituted by the halogen atom.

In a suitable embodiment of the present invention, formula (3) is a structural unit represented by formula (3 '), that is, at least a part of the plurality of Z is a structural unit represented by formula (3'). In this case, the optical member including the polyimide-based resin exhibits high surface hardness, has a low elastic modulus, and can have high flexibility.

[Formula 6]

In a suitable embodiment of the present invention, the content of the structural unit represented by the formula (3) with respect to the sum of Y and Z is preferably 3 mol% or more, more preferably 5 mol% or more, even more preferably Is at least 7 mol%, even more preferably at least 9 mol%, particularly preferably at least 15 mol%, very preferably at least 30 mol%, preferably at most 90 mol%, more preferably 87 mol% Or less, more preferably 85 mol% or less, particularly preferably 83 mol% or less, and very preferably 80 mol% or less. When the content rate of the structural unit represented by Formula (3) is more than the said lower limit with respect to the sum total of Y and Z, the optical member containing the said polyimide-type resin has low elasticity modulus, is excellent in flexibility, and at the same time high surface hardness Can be expressed. When the content rate of the structural unit represented by Formula (3) is below the said upper limit with respect to the sum total of Y and Z, it will suppress the thickening by the hydrogen bond between the amide bonds derived from Formula (3), Viscosity can be suppressed and the process of an optical member can be made easy. Further, the content of the structural unit represented by the formula (3) is, for example, may be calculated from the number, and the raw material or doipbi be measured by using a ¹ H-NMR.

In a preferred embodiment of the present invention, the polyimide resin is preferably 5 mol% or more, more preferably 7 mol% or more, even more preferably 9 mol% or more of Z in the polyimide resin. Especially preferably, 11 mol% or more is represented by Formula (3). When more than the said lower limit of Z in the said polyimide-type resin is represented by Formula (3), the optical member containing the said polyimide-type resin expresses high surface hardness, and has low elastic modulus and can have high flexibility. have. Moreover, it is preferable that 100 mol% or less of Z in the said polyimide resin is represented by Formula (3). Further, the content of the structural unit represented by the formula (3) in the polyimide-based resin is, for example, may be calculated from the number, and the raw material or doipbi be measured by using a ¹ H-NMR. It is preferable that the structural unit represented by said Formula (3) is a structural unit represented by Formula (3) when m is 1-4.

In a suitable embodiment of the present invention, the polyimide resin is a polyamideimide resin having a structural unit represented by formula (1) and a structural unit represented by formula (2).

In the said embodiment, content rate of the structural unit represented by Formula (1) in polyamideimide resin is with respect to the sum total of the structural unit represented by Formula (1) and the structural unit represented by Formula (2), Preferably it is 10 mol% or more, More preferably, it is 15 mol% or more, More preferably, it is 18 mol% or more, Especially preferably, it is 20 mol% or more, Preferably it is 90 mol% or less, More preferably, 70 mol% % Or less, More preferably, it is 60 mol% or less, Especially preferably, it is 50 mol% or less. In the said polyamideimide resin, when the content rate of the structural unit represented by Formula (1) is more than the said lower limit, the thickening by hydrogen bond between the amide bonds in Formula (2) is suppressed, and the viscosity of a polyamideimide varnish is reduced. It is possible to manufacture an optical member easily. In the said polyamideimide resin, when the content rate of the structural unit represented by Formula (1) is below the said upper limit, the optical member containing the said polyamideimide resin will exhibit high surface hardness. In addition, the said ratio can be measured using <^1> H-NMR, for example, or it can calculate it from the introduction ratio of a raw material.

In the said embodiment, content rate of the structural unit represented by Formula (2) in polyamideimide resin is with respect to the sum total of the structural unit represented by Formula (1) and the structural unit represented by Formula (2), Preferably it is 20 mol% or more, More preferably, it is 30 mol% or more, More preferably, it is 40 mol% or more, Especially preferably, it is 50 mol% or more, Preferably it is 90 mol% or less, More preferably, 80 mol% % Or less, More preferably, it is 75 mol% or less, Especially preferably, it is 70 mol% or less. In the said polyamideimide resin, when the content rate of the structural unit represented by Formula (1) is below the said upper limit, the thickening by the hydrogen bond between the amide bonds in Formula (2) is suppressed, and the viscosity of a polyamideimide varnish is reduced. It is possible to manufacture an optical member easily. In the said polyamideimide resin, if the content rate of the structural unit represented by Formula (1) is more than the said lower limit, the optical member containing the said polyamideimide resin will exhibit high surface hardness. In addition, the said ratio can be measured using <^1> H-NMR, for example, or it can calculate it from the introduction ratio of a raw material.

In the said embodiment, the ratio of the structural unit represented by Formula (3) with respect to the sum total of the structural unit represented by Formula (1) and the structural unit represented by Formula (2) in a polyamide-imide resin, Preferably at least 3 mol%, more preferably at least 5 mol%, even more preferably at least 7 mol%, even more preferably at least 9 mol%, particularly preferably at least 15 mol%, very preferably 30 It is at least mol%, preferably at most 90 mol%, more preferably at most 87 mol%, even more preferably at most 85 mol%, particularly preferably at most 83 mol%, very preferably at most 80 mol%. Regarding the sum of the structural units represented by the formula (1) and the structural units represented by the formula (2) in the polyamideimide resin, the ratio of the structural units represented by the formula (3) is equal to or greater than the lower limit, the polyamideimide An optical member comprising a resin has a low elastic modulus, excellent flexibility, and high surface hardness. Formula (3) is a ratio of the structural unit represented by Formula (3) with respect to the sum total of the structural unit represented by Formula (1) in a polyamide-imide resin, and the structural unit represented by Formula (2) below the said upper limit. By suppressing the thickening by the hydrogen bond between the derived amide bonds, the viscosity of the varnish of the polyamideimide resin can be suppressed and the processing of the optical member can be facilitated. Further, the content of the structural unit represented by the formula (3) is, for example, may be calculated from the number, and the raw material or doipbi be measured by using a ¹ H-NMR.

In Formula (1) and Formula (2), X represents a bivalent organic group each independently, Preferably it is a C4-C40 divalent organic group. The said organic group is the organic group in which the hydrogen atom in the organic group may be substituted by the hydrocarbon group or the fluorine-substituted hydrocarbon group, Preferably carbon number of a hydrocarbon group and a fluorine-substituted hydrocarbon group is 1-8. In addition, X in Formula (1) may be the same as or different from X in Formula (2).

In one embodiment of the present invention, the polyimide resin may include a plurality of types of X, and the plurality of types of X may be the same as or different from each other. As X, it is represented by the following formula (10), formula (11), formula (12), formula (13), formula (14), formula (15), formula (16), formula (17), or formula (18). Losing group; A group in which a hydrogen atom in the group represented by these formulas is substituted by a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; And a chain hydrocarbon group having 6 or less carbon atoms is exemplified.

[Formula 7]

[In formula (10), formula (11), formula (12), formula (13), formula (14), formula (15), formula (16), formula (17) or formula (18), * is a bond. Hands up,

V ^{1 to} V ³ each independently represent a single bond, -O-, -S-, -CH _2- , -CH ₂ -CH _2- , -CH (CH ₃ )-, and -C (CH ₃ ) ₂ -, -C (CF ₃ ) _2- , -SO _2- , -CO- or -N (Q). Here, Q represents a C1-C12 hydrocarbon group which may be substituted by the halogen atom.]

The bonding position for each ring of V ¹ and V ² and the bonding position for each ring of V ² and V ³ are each preferably a meta position or a para position, more preferably a para position, for each ring. to be.

Among the groups represented by the formulas (10), (11), (12), (13), (14), (15), (16), (17) or (18), From the viewpoint of the surface hardness and the flexibility of the optical member comprising the polyimide resin, a group represented by formula (13), formula (14), formula (15), formula (16) or formula (17) is preferable. , Group represented by formula (14), formula (15) or formula (16) is more preferable. In addition, V ^{1 to} V ³ are each independently from the viewpoint of surface hardness and flexibility of the optical member including the polyimide resin, preferably single bond, -O- or -S-, more preferably Is a single bond or -O-.

In a suitable embodiment of the present invention, in the case of the polyimide resin, in the case of the polyamideimide resin, at least a part of the plurality of X in the formula (1) and the formula (2) is represented by the formula (4) It is a structural unit represented by. If at least one part of some X is group represented by Formula (4), the optical member containing the said polyimide resin can express high transparency, and can express high surface hardness.

[Formula 8]

[In Formula (4), R <^10> , R <^11> , R <^12> , R <^13> , R <^14> , R <^15> , R <^16> and R <^17> are respectively independently a hydrogen atom, a C1-C6 alkyl group, or C6-C12 Represents an aryl group, and the hydrogen atoms contained in R ¹⁰ to R ¹⁷ may be each independently substituted with a halogen atom, and * represents a bond.]

In Formula (4), R <^10> , R <^11> , R <^12> , R <^13> , R <^14> , R <^15> , R <^16> and R <^17> are respectively independently a hydrogen atom, a C1-C6 alkyl group, or C6-C12 An aryl group is shown. As a C1-C6 alkyl group or a C6-C12 aryl group, an exemplary thing is mentioned as a C1-C6 alkyl group or C6-C12 aryl group in Formula (3). R ¹⁰ to R ¹⁷ each independently, preferably represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and more preferably represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, where R ¹⁰ to R ¹⁷ are The hydrogen atoms contained may be each independently substituted with a halogen atom. As a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned, for example. R ¹⁰ to R ¹⁷ are each independently, from the viewpoint of surface hardness, flexibility and transparency of the optical member including the polyimide resin, more preferably a hydrogen atom, a methyl group, a fluoro group, a chloro group or a tree It is a fluoromethyl group, Especially preferably, it is a hydrogen atom or a trifluoromethyl group.

In a preferred embodiment of the present invention, the structural unit represented by the formula (4) is a structural unit represented by the formula (4 '), that is, at least a part of the plurality of Xs is represented by the formula (4'). Unit. In this case, the optical member containing the said polyimide resin expresses high transparency, improves the solubility to the solvent of the said polyimide resin by the frame | skeleton containing a fluorine element, and polyimide-based resin The viscosity of the varnish containing can be suppressed low, and the process of an optical member can be made easy.

[Formula 9]

[In formula (4 '), * represents a bond.]

In a suitable embodiment of the present invention, X in the polyimide resin, preferably at least 30 mol%, more preferably at least 50 mol%, even more preferably at least 60 mol%, particularly preferably 70 mol More than% is represented by Formula (4), especially Formula (4 '). When X in the said range in the said polyimide-type resin is represented by Formula (4), especially Formula (4 '), the optical member containing this polyimide-type resin expresses high transparency, and is fluorine The frame | skeleton containing an element can improve the solubility to the solvent of the said polyimide resin, can suppress the viscosity of the varnish containing a polyimide resin low, and can also process the optical member easily. Moreover, Preferably, 100 mol% or less of X in the said polyimide resin is represented by Formula (4), especially Formula (4 '). Formula (4), especially Formula (4 ') may be sufficient as X in the said polyimide resin. The content of the constituent unit represented by formula (4) X in the polyimide-based resin is, for example, may be calculated from the number, and the raw material or doipbi be measured by using a ¹ H-NMR.

In the production method of the present invention, the glass transition temperature Tg calculated by tanδ in the dynamic viscoelasticity measurement (DMA measurement) of the polyimide resin is preferably less than 380 ° C, more preferably 379 ° C or less. Preferably it is 378 degreeC or less, for example, 370 degreeC It is as follows. When the glass transition temperature Tg of the polyimide-based resin is less than or equal to the above upper limit, the optical member comprising the polyimide-based resin exhibits high surface hardness and has a low elastic modulus and high flexibility. . In order to control a glass transition temperature to the said range, it is preferable to include as a monomer which comprises polyimide-type resin, the monomer which has a bivalent group which can provide flexibility to the polyimide-type resin film obtained by film forming, and has flexibility Specific examples of the divalent group which can be given include -O-, -CH _2- , -CF _2- , -C (CH ₃ ) _2-, and -C (CF ₃ ) _2- . As a monomer which has a bivalent group which can be provided, it is more preferable to include the monomer which has a bivalent group containing -O-. In addition, the said glass transition temperature Tg of polyimide-type resin is 300 degreeC or more normally.

In the manufacturing method of this invention, when a polyimide resin is a polyamideimide resin, the said polyamideimide resin is a formula (In addition to the structural unit represented by Formula (1) and the structural unit represented by Formula (2), The structural unit represented by 10-2) and / or the structural unit represented by Formula (11-2) may be included.

[Formula 10]

In Formula (10-2), Y <^1> is a tetravalent organic group each independently, Preferably it is the organic group which the hydrogen atom in the organic group may be substituted by the hydrocarbon group or the fluorine-substituted hydrocarbon group. As Y ^1, Formula (20), Formula (21), Formula (22), Formula (23), Formula (24), Formula (25), Formula (26), Formula (27), Formula (28), or Formula ( The group represented by 29) and a trivalent C6 or less chain hydrocarbon group are illustrated. Exemplary taeyangin polyamide-imide resin of the present invention, may include a plurality of types of Y ^1, Y ¹ of a plurality of species may be the same or different from each other.

In Formula (11-2), Y <^2> is a trivalent organic group, Preferably it is the organic group by which the hydrogen atom in the organic group may be substituted by the hydrocarbon group or the fluorine-substituted hydrocarbon group. Examples of Y ² the equations (20), Equation 21, Equation 22, Equation 23, Equation 24, Equation 25, Equation 26, Equation 27, Equation 28, or Examples of the group in which one of the bonds of the group represented by the formula (29) are substituted with a hydrogen atom and a trivalent C 6 or less chain hydrocarbon group are exemplified. Exemplary taeyangin polyamide-imide resin of the present invention, may include a plurality of types of Y ^2, Y ² is a plurality of types may be the same or different from each other.

In Formula (10-2) and Formula (11-2), X <^1> and X <^2> are respectively independently divalent organic groups, Preferably the hydrogen atom in an organic group is a hydrocarbon group or the fluorine-substituted hydrocarbon group. It is an organic group which may be substituted. X ¹ and X ^{2 are} represented by the following formulas (10), (11), (12), (13), (14), (15), (16), (17) or (18). Group represented by; A group in which a hydrogen atom in the group represented by these formulas is substituted by a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; And a chain hydrocarbon group having 6 or less carbon atoms is exemplified.

In one embodiment of the present invention, the polyamideimide resin is a structural unit represented by formula (1) and a structural unit represented by formula (2), and optionally formulas (10-2) and / or a formula. It consists of a structural unit represented by (11-2). Moreover, from the viewpoint of the flexibility and surface hardness of the optical member which consists of the said polyamideimide resin, in the said polyamideimide resin, the structural unit represented by Formula (1) and the structural unit represented by Formula (2) The content ratio is preferably 80% or more, based on 100% of the total of the entire structural units represented by the formulas (1) and (2) and, optionally, the formulas (10-2) and (11-2), More preferably, it is 90% or more, More preferably, it is 95% or more. In addition, in the said polyamideimide resin, the content rate of the structural unit represented by Formula (1) and the structural unit represented by Formula (2) is Formula (1) or Formula (2), or Formula (10) as needed. It is 100% or less normally based on -2) or all the structural units represented by Formula (11-2). In addition, the said content rate can be measured using <^1> H-NMR, for example, or it can also calculate from the introduction ratio of a raw material.

About the polyimide resin in the manufacturing method of this invention, a polyimide resin can be manufactured using the tetracarboxylic-acid compound and diamine compound mentioned later as a main raw material, for example. Moreover, polyamideimide resin can be manufactured using the tetracarboxylic acid compound, the dicarboxylic acid compound, and the diamine compound which are mentioned later as a main raw material, for example.

As tetracarboxylic acid compound used for the synthesis | combination of polyimide-type resin, Aromatic tetracarboxylic acid and its anhydride, Preferably aromatic tetracarboxylic acid compounds, such as the anhydride; And aliphatic tetracarboxylic acids and anhydrides thereof, preferably aliphatic tetracarboxylic acid compounds such as dihydrides thereof. A tetracarboxylic acid compound may be used independently and may use 2 or more types together. A tetracarboxylic-acid compound flexible body, such as an acid chloride compound, may be sufficient as a tetracarboxylic-acid compound. These can be used individually or in combination of 2 or more types.

As aromatic tetracarboxylic dianhydride, non-condensed polycyclic aromatic tetracarboxylic dianhydride, monocyclic aromatic tetracarboxylic dianhydride, and condensed polycyclic aromatic tetracarboxylic dianhydride are mentioned. Specific examples of the non-condensed polycyclic aromatic tetracarboxylic dianhydride include 4,4'-oxydiphthalic dianhydride (may be described as OPDA), 3,3 ', 4,4'-benzophenonetetracarboxylic acid 2 Anhydrides, 2,2 ', 3,3'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride (may be described as BPDA), 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride, 3,3', 4,4'-diphenylsulfontetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane 2 Anhydride, 2,2-bis (2,3-dicarboxyphenyl) propane 2 anhydride, 2,2-bis (3,4-dicarboxyphenoxyphenyl) propane 2 anhydride, 4,4 '-(hexafluoroiso Propylidene) diphthalic acid dianhydride (may be described as 6FDA), 1,2-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane 2 anhydride, 1,2-bis (3,4-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxype ) Ethane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, 4,4 '-(p-phenylenedioxy) diphthalic acid dianhydride, And 4,4 '-(m-phenylenedioxy) diphthalic anhydride. Moreover, as monocyclic aromatic tetracarboxylic dianhydride, 1,2,4,5-benzene tetracarboxylic dianhydride is used, and as condensed polycyclic aromatic tetracarboxylic dianhydride 1,2,4,5-benzene tetracarboxylic dianhydride As condensed polycyclic aromatic tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride is mentioned as main acid dianhydride. These can be used individually or in combination of 2 or more types.

Among these, 4,4'- oxydiphthalic acid dianhydride, 3,3 ', 4,4'- benzophenone tetracarboxylic dianhydride, 2,2', 3,3'- benzophenone tetracarboxylic dianhydride, 3 , 3 ', 4,4'-biphenyltetracarboxylic acid dianhydride, 2,2', 3,3'-biphenyltetracarboxylic acid dianhydride, 3,3 ', 4,4'-diphenylsulfontetracar Main acid dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, 2,2-bis (3,4- Dicarboxyphenoxyphenyl) propane dianhydride, 4,4 '-(hexafluoroisopropylidene) diphthalic acid dianhydride, 1,2-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1- Bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,2-bis (3,4-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, Bis (3,4-dicarboxyphenyl) methane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, 4,4 '-(p-phenylenedioxy) diphthalic acid dianhydride and 4,4'- (m- Nylenedioxy) diphthalic acid dianhydride is preferred, 4,4'-oxydiphthalic acid dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 4,4'-(hexafluoro Isopropylidene) diphthalic anhydride is more preferable.

As aliphatic tetracarboxylic dianhydride, a cyclic or acyclic aliphatic tetracarboxylic dianhydride is mentioned. A cyclic aliphatic tetracarboxylic dianhydride is tetracarboxylic dianhydride which has an alicyclic hydrocarbon structure, As an example, 1,2,4,5-cyclohexane tetracarboxylic dianhydride, 1,2,3,4-cyclo Cycloalkanetetracarboxylic dianhydride, such as butanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, bicyclo [2.2.2] oct-7-ene-2,3,5 And 6-tetracarboxylic dianhydride, dicyclohexyl-3,3 ', 4,4'-tetracarboxylic dianhydride and regioisomers thereof. These can be used individually or in combination of 2 or more types. Specific examples of the acyclic aliphatic tetracarboxylic dianhydride include 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-pentanetetracarboxylic dianhydride, and the like. Or it can use in combination of 2 or more type. Moreover, you may use combining cyclic aliphatic tetracarboxylic dianhydride and acyclic aliphatic tetracarboxylic dianhydride.

Among the tetracarboxylic dianhydrides, 4,4'-oxydiphthalic dianhydride, 3,3 ', 4,4 from the viewpoint of high surface hardness, high flexibility, high bending resistance, high transparency and low colorability of the optical member. '-Benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride, 3,3' , 4,4'-diphenylsulfontetracarboxylic acid dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 4,4 '-(hexafluoroisopropylidene) diphthalic acid dianhydride , And mixtures thereof are preferred, and 4,4'-oxydiphthalic anhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and 4,4'-(hexafluoroisopropylidene ) Diphthalic anhydride and mixtures thereof are more preferable, and 4,4 '-(hexafluoroisopropylidene) diphthalic anhydride is more preferable.

As a dicarboxylic acid compound used for the synthesis | combination of polyamideimide resin, it is preferable to include the compound represented by Formula (3 ").

[Formula 11]

[Formula (3 ') of, R ¹ ~R ⁸ are, each independently, a hydrogen atom contained in the hydrogen atom, an alkyl group or an aryl group having a carbon number of 6 to 12 carbon atoms of 1~6, R ¹ ~R ⁸ are, Each independently may be substituted by a halogen atom,

A is a single bond, -O-, -CH _2- , -CH ₂ -CH _2- , -CH (CH ₃ )-, -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -SO _2- , -S-, -CO- or -N (R ⁹ )-, R ⁹ represents a hydrocarbon group having 1 to 12 carbon atoms which may be substituted with a halogen atom,

m is an integer of 0 to 4,

R ³¹ and R ³² each independently represent a hydroxyl group, a methoxy group, an ethoxy group, an n-propoxy group, n-butoxy group or a chlorine atom.]

In a suitable embodiment, the dicarboxylic acid compound is a compound represented by formula (3 ") wherein m is 0, and further includes a compound represented by formula (3") wherein A is -O-. desirable. Moreover, in another suitable embodiment, a dicarboxylic acid compound is a compound represented by Formula (3 ") whose R <^32> is -Cl. Moreover, you may use a diisocyanate compound instead of a diamine compound. Terephthaloyl chloride may be used in addition to other dicarboxylic acid compounds, and other dicarboxylic acid compounds include 4,4′-oxybis benzoic acid and / or acid chloride compounds thereof. Examples of preferred dicarboxylic acid compounds include 4,4'-oxybis (benzoyl chloride), and other dicarboxylic acid compounds include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and flexible acid chloride compounds. And an acid anhydride etc., and may use 2 or more types together as a specific example, Terephthalic acid; isophthalic acid; naphthalenedicarboxylic acid; 4,4'-biphenyldicarboxylic acid; 3,3'- ratio Carbonyl dicarboxylic acid; a carbon number of 8 or less dicarboxylic acid compound, and two coupling two of the acid swaesik _{hydrocarbon, -CH 2 -, -C (CH} 3) 2 -, -C (CF 3) 2 -, -SO 2 - Or compounds linked by phenylene groups and their acid chloride compounds.

Moreover, the said polyimide resin is in addition to the tetracarboxylic-acid compound used for the synthesis | combination of said polyimide-type resin in the range which does not impair the various physical properties of the optical member which consists of the said polyimide-type resin, The carboxylic acid and tricarboxylic acid and their anhydrides and derivatives may be further reacted.

As tetracarboxylic acid, the water adduct of the anhydride of the said tetracarboxylic acid compound is mentioned.

Examples of the tricarboxylic acid compound include aromatic tricarboxylic acid, aliphatic tricarboxylic acid, their flexible acid chloride compounds, and acid anhydrides, and two or more kinds thereof may be used in combination. Specific examples include anhydrides of 1,2,4-benzenetricarboxylic acid; 2,3,6-naphthalenetricarboxylic acid-2,3- anhydride; And phthalic anhydride and benzoic acid are linked by a single bond, -O-, -CH _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -SO ₂ -or a phenylene group. .

As a diamine compound used for the synthesis | combination of a polyimide resin, aliphatic diamine, aromatic diamine, and mixtures thereof are mentioned, for example. In addition, in this embodiment, "aromatic diamine" shows the diamine which the amino group couple | bonded with the aromatic ring directly, and may contain the aliphatic group or other substituent in a part of the structure. The aromatic ring may be monocyclic or condensed ring, and examples thereof include, but are not limited to, a benzene ring, a naphthalene ring, an anthracene ring and a fluorene ring. Among these, a benzene ring is preferable. Moreover, "aliphatic diamine" shows the diamine which the amino group couple | bonded with the aliphatic group directly, and may contain the aromatic ring and other substituent in a part of the structure.

Examples of the aliphatic diamine include acyclic aliphatic diamines such as hexamethylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, norbornanediamine, and 4, Cyclic aliphatic diamine, such as 4'- diamino dicyclohexyl methane, etc. are mentioned. These can be used individually or in combination of 2 or more types.

Examples of the aromatic diamines include p-phenylenediamine, m-phenylenediamine, 2,4-toluenediamine, m-xylylenediamine, p-xylylenediamine, 1,5-diaminonaphthalene, and Aromatic diamines having one aromatic ring, such as 2,6-diaminonaphthalene; 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether (may be described as ODA), 3,4'-diaminodi Phenylether, 3,3'-diaminodiphenylether, 4,4'-diaminodiphenylsulfone, 3,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 1,4 -Bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy ) Phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2'-dimethylbenzidine (May be described as MB), 2,2'-bis (trifluoromethyl) benzidine (may be described as TFMB), 4,4'-bis (4-aminophenoxy) biphenyl, 9 , 9-bis (4-aminophenyl) fluorene, 9,9-bis (4-amino-3-methylphenyl) fluorene, 9,9-bis (4-amino-3-chlorophenyl) fluorene, and 9 , 9-bis (4-amino-3-fluoro There may be mentioned phenyl) fluorene, etc., an aromatic diamine having an aromatic ring at least two. These can be used individually or in combination of 2 or more types.

As aromatic diamine, Preferably, 4,4'- diamino diphenylmethane, 4,4'- diamino diphenyl propane, 4,4'- diamino diphenyl ether, 3,3'- diamino diphenyl ether , 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 1,4-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] Sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy ) Phenyl] propane, 2,2'-dimethylbenzidine, 2,2'-bis (trifluoromethyl) -4,4'-diaminodiphenyl, 4,4'-bis (4-aminophenoxy) ratio Phenyl, more preferably 4,4'-diaminodiphenyl methane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylether, 4,4'-diamino Diphenylsulfone, 1,4-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] Propane, 2,2'-dimethylbenzidine, And 2,2'-bis (trifluoromethyl) benzidine and 4,4'-bis (4-aminophenoxy) biphenyl. These can be used individually or in combination of 2 or more types.

Among the diamine compounds, at least one member selected from the group consisting of aromatic diamines having a biphenyl structure is preferably used from the viewpoint of high surface hardness, high flexibility, high bending resistance, high transparency and low colorability of the optical member. Consisting of 2,2'-dimethylbenzidine, 2,2'-bis (trifluoromethyl) benzidine, 4,4'-bis (4-aminophenoxy) biphenyl and 4,4'-diaminodiphenylether It is more preferable to use 1 or more types selected from the group, and even more preferably to use 2,2'-bis (trifluoromethyl) benzidine.

The polyamideimide resin which is one embodiment of the present invention includes a diamine compound, a tetracarboxylic acid compound (tetracarboxylic acid compound flexible body such as an acid chloride compound and tetracarboxylic dianhydride), and a dicarboxylic acid compound (acid chloride compound, etc.). Dicarboxylic acid compound flexible body) and, optionally, a tricondensation polymer which is a polycondensation product with a tricarboxylic acid compound (tricarboxylic acid compound flexible body such as an acid chloride compound or a tricarboxylic acid anhydride).

The structural units represented by the formulas (1) and (10-2) are usually derived from diamines and tetracarboxylic acid compounds. The structural unit represented by Formula (2) is usually derived from a diamine and a dicarboxylic acid compound. The structural unit represented by Formula (11-2) is usually derived from a diamine and a tricarboxylic acid compound.

In a preferred embodiment of the present invention, the polyimide resin may include a halogen atom as described above. As a specific example of a fluorine-containing substituent, a fluoro group and a trifluoromethyl group are mentioned. When the polyimide resin contains a halogen atom, the yellowness (sometimes referred to as YI) of the optical member including the polyimide resin may be reduced, and both high flexibility and flex resistance can be achieved. There is a tendency to. In addition, the halogen atom is preferably a fluorine atom from the viewpoint of reducing the yellowness of the optical member (that is, improving transparency), decreasing the absorption rate, and the bend resistance.

The content rate of the halogen atom in polyimide-type resin is based on the mass of polyimide-type resin from a viewpoint of the reduction of yellowness (improvement of transparency), a decrease in water absorption, and suppression of deformation of an optical member, Preferably Is 1-40 mass%, More preferably, it is 3-35 mass%, More preferably, it is 5-32 mass%.

In one embodiment of the present invention, an imidation catalyst may be present in the synthesis reaction of the polyimide resin. As an imidation catalyst, For example, aliphatic amines, such as tripropylamine, dibutylpropylamine, and ethyl dibutylamine; Alicyclic amines (monocyclic) such as N-ethylpiperidine, N-propylpiperidine, N-butylpyrrolidine, N-butylpiperidine, and N-propylhexahydroazepine; Alicyclic amines (polycyclic) such as azabicyclo [2.2.1] heptane, azabicyclo [3.2.1] octane, azabicyclo [2.2.2] octane, and azabicyclo [3.2.2] nonane; And pyridine, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 3-ethylpyridine, 4-ethylpyridine, 2,4-dimethylpyridine, 2,4,6-trimethylpyridine, 3 And aromatic amines such as, 4-cyclopentenopyridine, 5,6,7,8-tetrahydroisoquinoline, and isoquinoline.

Although the reaction temperature of a diamine compound, a dicarboxylic acid compound, and a tetracarboxylic acid compound in some cases is not specifically limited, For example, it is 50-350 degreeC. Although reaction time is not specifically limited, for example, It is about 30 minutes-about 10 hours. If necessary, the reaction may be performed under inert atmosphere or reduced pressure. Moreover, you may perform reaction in a solvent, As the solvent, the solvent mentioned later used for preparation of the varnish containing polyimide-type resin is mentioned, for example.

The polyimide resin powder manufactured by the manufacturing method of this invention can be used, for example for manufacture of an optical member. As an optical member, an optical film is mentioned, for example. Since the said optical member is excellent in flexibility, bending resistance, and surface hardness, it is suitable as a front plate of an image display apparatus, especially a front plate (window film) of a flexible display. The optical member may be a single layer or a multilayer. In the case where the optical member is a multilayer, each layer may have the same composition or different compositions.

When using the polyimide resin powder manufactured by the manufacturing method of this invention for manufacture of an optical member, the content rate of the polyimide resin in an optical member becomes like this. Preferably it is 40 mass with respect to the total mass of an optical member. It is more than%, More preferably, it is 50 mass% or more, More preferably, it is 70 mass% or more, Especially preferably, it is 80 mass% or more, Very preferably 90 mass% or more. If the content rate of polyimide resin is more than the said lower limit, the bending resistance of an optical member is favorable. In addition, the content rate of polyimide resin in an optical member is 100 mass% or less normally with respect to the total mass of an optical member.

(Inorganic materials)

The optical member may further contain inorganic materials such as inorganic particles in addition to the polyimide resin. Examples of the inorganic material include inorganic particles such as titania particles, alumina particles, zirconia particles, and silica particles, and silicon compounds such as quaternary alkoxysilanes such as tetraethyl orthosilicate. From the viewpoint of the stability of the varnish containing the polyimide resin for producing the optical member, the inorganic material is preferably inorganic particles, particularly silica particles. The inorganic particles may be bonded by a molecule having a siloxane bond.

The average primary particle size of the inorganic particles is usually 1 to 100 nm or more, preferably 5 to 80 nm, more preferably 7 to 8 from the viewpoint of transparency of the optical member, mechanical properties, and suppression of aggregation of the inorganic particles. 50 nm, More preferably, it is 10-30 nm. In this invention, an average primary particle diameter can be determined by measuring the 10-point average value of the forward diameter by a transmission electron microscope.

The content of the inorganic material in the optical member is preferably 0% by mass or more and 90% by mass or less, more preferably 0.01% by mass or more and 60% by mass or less, further preferably 5% by mass based on the total mass of the optical member. It is more than 40 mass% in%. When the content rate of the inorganic material is within the above range, there is a tendency to make both the transparency and mechanical properties of the optical member compatible.

(UV absorber)

The optical member may contain 1 type, or 2 or more types of ultraviolet absorbers. A ultraviolet absorber can be suitably selected from what is normally used as a ultraviolet absorber in the field of resin materials. The ultraviolet absorber may contain the compound which absorbs the light of the wavelength of 400 nm or less. As an ultraviolet absorber, the at least 1 sort (s) of compound chosen from the group which consists of a benzophenone type compound, a salicylate type compound, a benzotriazole type compound, and a triazine type compound is mentioned, for example. Since an optical member contains a ultraviolet absorber, deterioration of polyimide resin can be suppressed, and the visibility of an optical member can be improved.

In addition, in this specification, a "system compound" refers to the derivative of the compound to which the said "system compound" is affixed. For example, a "benzophenone type compound" refers to a compound having a benzophenone as a parent skeleton and a substituent bonded to the benzophenone.

When the optical member contains a ultraviolet absorber, the content of the ultraviolet absorber is preferably 1% by mass or more, more preferably 2% by mass or more, further preferably 3% by mass or more, based on the total mass of the optical member. Preferably it is 10 mass% or less, More preferably, it is 8 mass% or less, More preferably, it is 6 mass% or less. Although an appropriate content rate changes with the ultraviolet absorber to be used, if the content rate of an ultraviolet absorber is adjusted so that the light transmittance of 400 nm may be about 20 to 60%, the light resistance of an optical member will become high and an optical member with high transparency can be obtained.

(Other additives)

The optical member may further contain other additives. As other components, antioxidant, a mold release agent, a stabilizer, a bluing agent, a flame retardant, a pH adjuster, a silica dispersant, a lubricating agent, a thickener, a leveling agent, etc. are mentioned, for example.

The content rate of the other additives is preferably 0% by mass or more and 20% by mass or less, more preferably 0% by mass or more and 10% by mass or less with respect to the mass of the optical member.

Although the thickness of an optical member, especially an optical film is suitably adjusted according to a use, it is 10-1000 micrometers normally, Preferably it is 15-500 micrometers, More preferably, it is 20-400 micrometers, More preferably, it is 25-300 micrometers. In the present invention, the thickness can be measured by a contact type digital indicator.

The total light transmittance Tt in the optical member is preferably 70% or more, more preferably 80% or more, still more preferably 85% or more, and particularly preferably 90% or more. When the total light transmittance Tt of the optical member is equal to or greater than the lower limit, sufficient visibility can be easily secured when the optical member is assembled into the image display device, and, for example, on the visual side, compared with the case where the transmittance is not in the range. In the case of obtaining the same brightness, the illuminance of the backlight can be reduced, which can contribute to energy saving. In addition, the upper limit of the total light transmittance Tt of an optical member is 100% or less normally. Haze in the optical member is measured by a direct reading haze computer (type HGM-2DP) manufactured by Suga Tester Co., Ltd., preferably 1.0% or less, more preferably 0.8% or less, even more preferably Is 0.5% or less, particularly preferably 0.3% or less. When the haze of an optical member is below the said upper limit, sufficient visibility is easy to be ensured, when an optical member is assembled to flexible electronic devices, such as an image display apparatus. In addition, the lower limit of the said haze is not specifically limited, What is necessary is just 0% or more. The polyimide-based resin dissolved in the polyimide-based resin solution (a) used in the production method of the present invention, and / or the powder of the polyimide-based resin obtained by the production method of the present invention includes the total light transmittance Tt and It is preferred to have haze. The total light transmittance Tt and / or haze of polyimide-type resin and polyimide-type resin powder are measured in the shape of a molded object (for example, a film). The total light transmittance may be measured based on JIS K 7105: 1981 or JIS K 7361-1: 1997.

(Method for Manufacturing Optical Member)

Using the polyimide resin powder manufactured by the manufacturing method of this invention, the above optical members, for example, an optical film can be manufactured. The manufacturing method is not particularly limited. For example, the following process:

(a) Process of apply | coating the liquid (varnish of polyimide-type resin) containing polyimide-type resin obtained by melt | dissolving a polyimide-type resin powder to a solvent, and forming a coating film (coating process), And

(b) Process of forming the optical member, especially the optical film (polyimide resin film) by drying the applied liquid (varnish of polyimide resin) (forming step)

An optical member can be manufactured by the manufacturing method containing this. Process (a) and (b) can be normally performed in this order.

In the coating step, the polyimide resin powder is dissolved in a solvent, and the above-described ultraviolet absorber and other additives are added and stirred as necessary to prepare a liquid containing a polyimide resin (varnish of polyimide resin). To prepare.

The solvent used for preparation of the varnish is not particularly limited as long as it can dissolve the polyimide resin. As such a solvent, For example, Amide type solvents, such as N, N- dimethylacetamide and N, N- dimethylformamide; lactone solvents such as γ-butyrolactone and γ-valerolactone; Sulfur-containing solvents such as dimethyl sulfone, dimethyl sulfoxide and sulfolane; Carbonate solvents such as ethylene carbonate and propylene carbonate; And combinations thereof. Among these solvents, amide solvents or lactone solvents are preferable. The varnish may also contain water, an alcohol solvent, a ketone solvent, an acyclic ester solvent, an ether solvent, or the like.

Next, casting is performed by using a varnish of polyimide-based resin on a substrate such as a resin substrate, an SUS belt, or a glass substrate by a known roll-to-roll or a batch method. A coating film can be formed by etc.

In a formation process, an optical member can be formed by drying a coating film and peeling from a base material. You may perform the drying process which dries an optical member further after peeling. Drying of a coating film can be performed at the temperature of 50-350 degreeC normally. As needed, you may dry a coating film under conditions of inert atmosphere or reduced pressure.

You may perform the surface treatment process which surface-treats on at least one surface of an optical member. As surface treatment, UV ozone treatment, a plasma treatment, and a corona discharge treatment are mentioned, for example.

Examples of the resin substrate include PET films, PEN films, polyimide films, polyamideimide films and the like, and from the viewpoint of excellent heat resistance, preferably PET films, PEN films, polyimide films, and other polyamides A mid film is mentioned, More preferably, PET film is mentioned from a viewpoint of adhesiveness with an optical member, and a cost.

An optical member can be manufactured using the polyimide resin powder obtained by the manufacturing method of this invention. Such an optical member has high elastic modulus and flexibility. In a suitable embodiment of the present invention, the elastic modulus of the optical member is preferably 3.0 GPa or more, more preferably 4.0 GPa or more, still more preferably 5.0 GPa or more, particularly preferably 6.0 GPa or more, preferably Is 10.0 kPa or less, More preferably, it is 8.0 kPa or less, More preferably, it is 7.0 kPa or less. Said upper limit and lower limit can be combined arbitrarily. When the elasticity modulus of an optical member exists in the said range, when using for a flexible display, it has sufficient hardness, and when the flexible display is bent, damage of the other member by the said optical member can be suppressed. The elastic modulus is measured, for example, using an autograph AG-IS manufactured by Shimadzu Corporation, and measuring the SS curve under conditions of a distance of 500 mm and a tensile speed of 20 mm / min for a 10 mm wide test piece. It can measure from the inclination. The polyimide resin dissolved in the polyimide resin solution (a) used in the production method of the present invention, and / or the powder of the polyimide resin obtained by the production method of the present invention has the above elastic modulus. desirable. The elasticity modulus of polyimide-type resin and polyimide-type resin powder is measured by a molded object (for example, the shape of a film).

The optical member, in particular the optical film, has excellent flex resistance. In a suitable embodiment of the present invention, the optical member has a reciprocating bending number of times until fracture when measured at a speed of 175 cpm at 135 ° at a load of 0.75 kgf at R = 1 mm, preferably 10,000 or more times. It is preferably at least 20,000 times, more preferably at least 30,000 times, even more preferably at least 40,000 times, particularly preferably at least 50,000 times, very preferably at least 100,000 times.

When the frequency | count of reciprocation bending of an optical member is more than the said lower limit, it is easier to suppress the folding wrinkle which may arise when bending an optical member. The number of reciprocating bends of the optical member is better as the number of times increases, and the upper limit thereof is not particularly limited. For example, 1,000,000 times or less may be sufficient. The number of reciprocating bends can be obtained, for example, by using a test piece (optical member) having a thickness of 50 μm and a width of 10 mm using an MIT internal fatigue tester (type 0530) manufactured by Toyo Seiki Co., Ltd. The polyimide resin dissolved in the polyimide resin solution (a) used in the production method of the present invention, and / or the powder of the polyimide resin obtained by the production method of the present invention has the above bending resistance. It is preferable. Flexural resistance of a polyimide-type resin and polyimide-type resin powder is measured in the shape of a molded object (for example, a film).

The optical member can express excellent transparency. Therefore, the said optical member is very useful as an image display apparatus, especially the front plate (window film) of a flexible display. In a suitable embodiment of the present invention, the optical member has a yellowness YI in accordance with JIS K 7373: 2006, preferably 5 or less, more preferably 3 or less, still more preferably 2.5 or less, particularly preferably 2.0 or less. The optical member whose yellowness YI is below the said upper limit can contribute to high visibility, such as a display apparatus. In addition, the yellowness of the optical member is preferably 0 or more. The polyimide resin dissolved in the polyimide resin solution (a) to be used in the production method of the present invention, and / or the powder of the polyimide resin obtained by the production method of the present invention is the yellowness YI. It is desirable to have. Yellowness YI of polyimide-type resin and polyimide-type resin powder is measured in the shape of a molded object (for example, a film).

The optical member may be provided with a functional layer such as an ultraviolet absorbing layer, an adhesive layer, a color adjusting layer, a refractive index adjusting layer, or a hard coating layer.

The optical member (for example, optical film) manufactured using the polyimide resin powder of this invention is a front panel of an image display apparatus, especially the front panel (window film) of a flexible display, especially a foldable display and a roller. It is useful as the front panel of a single display. The optical member can be arranged as a front plate on the visual side of an image display device, particularly a flexible display. This front plate has a function of protecting the image display element in the flexible display. Since the image display device including the optical member has high flexibility and flex resistance, and has a high surface hardness, it does not damage other members when bent, and it is difficult to form wrinkles in the optical member itself. The surface scratches can be more advantageously suppressed.

As an image display apparatus, wearable devices, such as a television, a smart phone, a mobile telephone, car navigation, a tablet PC, a portable game machine, an electronic paper, an indicator, a bulletin board, a clock, and a smart watch, etc. are mentioned. As a flexible display, the image display apparatus which has a flexible characteristic, for example, a television, a smart phone, a mobile telephone, car navigation, a tablet PC, a portable game machine, an electronic paper, an indicator, a bulletin board, a clock, a wearable device, etc. are mentioned.

[Flexible Display]

This invention also provides the flexible display provided with the optical film of this invention. The optical film of the present invention is preferably used as a front plate in a flexible display, and the front plate may be called a window film. The said flexible display consists of a laminated body for flexible displays, and an organic electroluminescent display panel, The flexible display laminated body is arrange | positioned at the visual recognition side with respect to an organic electroluminescent display panel, and is comprised so that it is bendable. The laminated body for flexible displays may contain a window film, a polarizing plate (preferably circularly polarizing plate), and a touch sensor, and although the lamination order is arbitrary, it is a window film, a polarizing plate, a touch sensor, or a window film, a touch sensor from the visual recognition side. It is preferable to laminate | stack in order of the polarizing plate. When a polarizing plate exists in the visual recognition side of a touch sensor, since the pattern of a touch sensor becomes difficult to see and the visibility of a display image becomes favorable, it is preferable. Each member can be laminated | stacked using an adhesive agent, an adhesive, etc. The light shielding pattern may be provided on at least one surface of any of the window film, the polarizing plate, and the touch sensor.

[Polarizing Plate]

The flexible display of the present invention may further include a polarizing plate, preferably a circular polarizing plate. A circular polarizing plate is a functional layer which has a function which transmits only right or left circularly polarizing component by laminating | stacking (lambda) / 4 phase (s) difference plate in a linear polarizing plate. For example, it is used to convert external light into right polarized light to block external light reflected by the organic EL panel to become left circularly polarized light, and to suppress the influence of reflected light by transmitting only the light emitting components of the organic EL to make the image easier to see. In order to achieve the circularly polarized light function, the absorption axis of the linear polarizing plate and the ground axis of the λ / 4 retardation plate need to be 45 ° in theory, but are practically 45 ± 10 °. The linear polarizing plate and the λ / 4 retardation plate do not necessarily have to be stacked adjacent to each other, and the relationship between the absorption axis and the slow axis only needs to satisfy the aforementioned range. Although it is preferable to achieve complete circular polarization in all wavelengths, since it does not necessarily need to be practical, the circular polarizing plate in this invention also includes an elliptical polarizing plate. It is also preferable to improve the visibility in the state which used polarized sunglass by laminating | stacking (lambda) / 4 phase (s) difference film further on the visual recognition side of a linear polarizing plate, and making outgoing light circularly polarized.

The linear polarizer is a functional layer having a function of passing light that vibrates in the transmission axis direction but blocking polarization of the vibration component perpendicular to the linear polarizer. The linear polarizing plate may be a structure including a linear polarizer alone or a linear polarizer and a protective film affixed to at least one surface thereof. The thickness of the said linear polarizing plate may be 200 micrometers or less, Preferably it is 0.5-100 micrometers. When thickness exists in the said range, it exists in the tendency for flexibility to fall easily.

The linear polarizer may be a film polarizer manufactured by dyeing and stretching a polyvinyl alcohol (PVA) film. A dichroic dye is orientated and exhibits polarization performance by extending | stretching in the state which the dichroic dye, such as iodine, adsorb | sucked to PVA system film oriented by extending | stretching, or adsorb | sucking to PVA. In manufacture of the said film polarizer, you may have other processes, such as swelling, bridge | crosslinking by boric acid, washing | cleaning by aqueous solution, and drying. The stretching or dyeing step may be performed by a PVA film alone, or may be performed in a state of being laminated with other films such as polyethylene terephthalate. The thickness of the PVA-based film used is preferably 10 to 100 µm, and the draw ratio is preferably 2 to 10 times.

Moreover, as another example of the said polarizer, the liquid crystal coating type polarizer formed by apply | coating and forming a liquid crystal polarizing composition may be sufficient. The liquid crystal polarizing composition may include a liquid crystal compound and a dichroic dye compound. The said liquid crystalline compound should just have the property to show a liquid crystal state, and especially since it can exhibit high polarization performance, if it has high order orientation states, such as a smectic phase, it is preferable. Moreover, it is also preferable that a liquid crystalline compound has a polymeric functional group.

The said dichroic dye is a pigment | dye which orientates together with the said liquid crystal compound, and shows dichroism, The dichroic dye itself may have liquid crystallinity, and may have a polymeric functional group. Any compound in the liquid crystal polarizing composition has a polymerizable functional group.

The liquid crystal polarizing composition may further include an initiator, a solvent, a dispersant, a leveling agent, a stabilizer, a surfactant, a crosslinking agent, a silane coupling agent, and the like.

The said liquid crystal polarizing layer is manufactured by apply | coating a liquid crystal polarizing composition on an oriented film, and forming a liquid crystal polarizing layer.

The liquid crystal polarizing layer can be formed thinner than the film polarizer. The thickness of the liquid crystal polarizing layer is preferably 0.5 to 10 m, more preferably 1 to 5 m.

The said orientation film can be manufactured by apply | coating an orientation film formation composition on a base material, for example, and providing orientation by rubbing, polarized light irradiation, etc. The alignment film forming composition may contain a solvent, a crosslinking agent, an initiator, a dispersant, a leveling agent, a silane coupling agent, or the like in addition to the alignment agent. As said alignment agent, polyvinyl alcohol, polyacrylates, polyamic acid, polyimide can be used, for example. When applying photo-alignment, it is preferable to use the aligning agent containing a cinnamate group. The weight average molecular weight of the polymer used as the aligning agent may be about 10,000 to 1,000,000. The thickness of the alignment film is preferably 5 to 10,000 nm, more preferably 10 to 500 nm from the viewpoint of the orientation regulation force. The liquid crystal polarizing layer may be peeled off from the substrate, transferred and laminated, or the substrate may be laminated as it is. It is also preferable that the said base material plays a role as a transparent base material of a protective film, a retardation plate, and a window.

As said protective film, what is necessary is just a transparent polymer film, and the material and additive used for the said transparent base material can be used. Cellulose films, olefin films, acrylic films, polyester films are preferred. The coating type protective film obtained by apply | coating and hardening cationic curing compositions, such as an epoxy resin, and radical curing compositions, such as an acrylate, may be sufficient. If necessary, plasticizers, ultraviolet absorbers, infrared absorbers, coloring agents such as pigments and dyes, fluorescent brighteners, dispersants, thermal stabilizers, light stabilizers, antistatic agents, antioxidants, lubricants, solvents and the like may be included. The thickness of the said protective film may be 200 micrometers or less, Preferably it is 1-100 micrometers. When the thickness of the said protective film exists in said range, the flexibility of a protective film will not fall easily. A protective film can also serve as the transparent base material of a window.

The said (lambda) / 4 phase (s) difference plate is a film which provides the phase difference of (lambda) / 4 in the direction (in-plane direction of a film) orthogonal to the advancing direction of incident light. The λ / 4 retardation plate may be an oriented retardation plate produced by stretching a polymer film such as a cellulose film, an olefin film, or a polycarbonate film. If necessary, phase retarder, plasticizer, ultraviolet absorber, infrared absorber, colorant such as pigment or dye, fluorescent brightener, dispersant, heat stabilizer, light stabilizer, antistatic agent, antioxidant, lubricant, solvent and the like may be included. The thickness of the said stretchable phase difference plate may be 200 micrometers or less, Preferably it is 1-100 micrometers. When thickness exists in the said range, there exists a tendency for the flexibility of a film to fall easily.

Moreover, as another example of the said (lambda) / 4 phase (s) difference plate, the liquid crystal coating type phase difference plate formed by apply | coating and forming a liquid crystal composition may be sufficient. The liquid crystal composition contains a liquid crystalline compound having properties such as nematic, cholesteric, smectic and so forth. Any compound containing the liquid crystalline compound in the liquid crystal composition has a polymerizable functional group. The liquid crystal coating type retardation plate may further include an initiator, a solvent, a dispersant, a leveling agent, a stabilizer, a surfactant, a crosslinking agent, a silane coupling agent, and the like. The said liquid crystal coating type phase difference plate can be manufactured by apply | coating and hardening a liquid crystal composition on an oriented film similarly to the base material in the said liquid crystal polarizing layer, and forming a liquid crystal phase difference layer. The liquid crystal coating type retardation plate can be formed thinner than the stretchable retardation plate. The thickness of the liquid crystal polarizing layer is usually 0.5 to 10 m, preferably 1 to 5 m. The liquid crystal coating type retardation plate may be peeled off from the substrate, transferred and laminated, or the substrate may be laminated as it is. It is also preferable that the said base material plays a role as a transparent base material of a protective film, a retardation plate, and a window.

In general, the shorter the wavelength, the larger the birefringence, and the longer the wavelength, the more material exhibits the small birefringence. In this case, the phase difference of λ / 4 cannot be achieved in the entire visible light region. Therefore, in-plane retardation 100 to 180 nm, preferably 130 to 150 nm, such as λ / 4 with respect to the vicinity of 560 nm where the visibility is high It is often designed to be. It is preferable to use a reverse dispersion lambda / 4 retardation plate using a material having a birefringence wavelength dispersion characteristic opposite to that of normal, since the visibility can be improved. As such a material, it is also preferable to use what is described in Unexamined-Japanese-Patent No. 2010-30979 in the case of a liquid crystal coating type retardation plate, such as Unexamined-Japanese-Patent No. 2007-232873 in the case of a stretchable retardation plate.

As another method, a technique for obtaining a wideband [lambda] / 4 retardation plate by combining with a [lambda] / 2 retardation plate is also known (Japanese Patent Laid-Open No. 10-90521). The lambda / 2 phase difference plate is also manufactured by the same material method as the lambda / 4 phase difference plate. Although the combination of an extending | stretching retardation plate and a liquid crystal coating type retardation plate is arbitrary, it is preferable to use a liquid crystal coating type retardation plate in any case, since thickness can be made thin.

In order to improve the visibility of an oblique direction, the method of laminating | stacking a positive C plate is also known to the said circularly polarizing plate (Unexamined-Japanese-Patent No. 2014-224837). The liquid crystal coating type retardation plate may be sufficient as a positive C plate, and a extending | stretching retardation plate may be sufficient as it. The phase difference in the thickness direction is -200 to -20 nm, preferably -140 to -40 nm.

[Touch sensor]

The flexible display of this invention may further be equipped with the touch sensor. The touch sensor is used as an input means. As a touch sensor, various forms, such as a resistive film type, a surface acoustic wave type, an infrared type, an electromagnetic induction type, and a capacitive type, are proposed, and may be any type. Among them, the capacitive method is preferable. The capacitive touch sensor is divided into an active region and an inactive region positioned at an outer portion of the active region. The active area corresponds to an area (display unit) on which a screen is displayed by the display panel. The active area corresponds to an area where a user's touch is detected. Area. The touch sensor includes a substrate having a flexible characteristic; A sensing pattern formed in an active region of the substrate; Each sensing line may be formed in an inactive region of the substrate and may be connected to an external driving circuit through the sensing pattern and the pad unit. As a board | substrate which has a flexible characteristic, the material similar to the transparent substrate of the said window can be used. It is preferable that the toughness of the board | substrate of a touch sensor is 2,000 Mpa% or more from the point of crack suppression of a touch sensor. More preferably, the toughness may be 2,000 to 30,000 MPa%. Here, toughness is defined as the lower area of the curve from the stress (MPa) -strain (%) curve obtained through the tensile test of the polymer material to the break point.

The sensing pattern may include a first pattern formed in a first direction and a second pattern formed in a second direction. The first pattern and the second pattern are arranged in different directions. The first pattern and the second pattern are formed on the same layer and each pattern must be electrically connected in order to detect the touched point. The first pattern has a form in which each unit pattern is connected to each other via a seam, but the second pattern has a structure in which each unit pattern is separated from each other in an island form, so that a separate bridge electrode is used to electrically connect the second pattern. This is necessary. The sensing pattern may apply a well-known transparent electrode material. For example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc oxide (IZTO), indium gallium zinc oxide (IGZO), cadmium tin oxide (CTO), PEDOT (poly (3,4-ethylenedioxythiophene)), carbon nanotubes (CNT), graphene, metal wires, and the like, and these may be used alone or in combination of two or more thereof. Preferably ITO can be used. The metal used for a metal wire is not specifically limited, For example, silver, gold, aluminum, copper, iron, nickel, titanium, selenium, chromium, etc. are mentioned. These can be used individually or in mixture of 2 or more types.

The bridge electrode may be formed on the insulating layer over the sensing pattern, the bridge electrode is formed on the substrate, and the insulating layer and the sensing pattern may be formed thereon. The bridge electrode may be formed of the same material as the sensing pattern, or may be formed of a metal such as molybdenum, silver, aluminum, copper, palladium, gold, platinum, zinc, tin, titanium, or an alloy of two or more thereof. Since the first pattern and the second pattern must be electrically insulated, an insulating layer is formed between the sensing pattern and the bridge electrode. The insulating layer may be formed only between the joint of the first pattern and the bridge electrode, or may be formed in the structure of the layer covering the sensing pattern. In the latter case, the bridge electrode can connect the second pattern through the contact hole formed in the insulating layer. The touch sensor appropriately compensates for the difference in light transmittance caused by the difference in transmittance between the patterned pattern region and the non-patterned region in which the pattern is not formed, specifically, the refractive index difference in these regions. As a means for it may further comprise an optical control layer between the substrate and the electrode, the optical control layer may comprise an inorganic insulating material or an organic insulating material. The optical control layer may be formed by coating a photocurable composition including a photocurable organic binder and a solvent on a substrate. The photocurable composition may further include an inorganic particle. The refractive index of the optical control layer can be increased by the inorganic particles.

The photocurable organic binder may include, for example, a copolymer of each monomer such as an acrylate monomer, a styrene monomer, a carboxylic acid monomer, and the like. The said photocurable organic binder may be a copolymer containing each different repeating unit, such as an epoxy group containing repeating unit, an acrylate repeating unit, and a carboxylic acid repeating unit, for example.

The inorganic particles may include, for example, zirconia particles, titania particles, alumina particles, and the like. The said photocuring composition may further contain each additive, such as a photoinitiator, a polymerizable monomer, and a hardening adjuvant.

[Adhesive layer]

Each layer (window, polarizing plate, touch sensor) which forms the said laminated body for flexible displays, and the film member (linear polarizing plate, (lambda) / 4 phase (s) difference plate, etc.) which comprise each layer can be adhere | attached with an adhesive agent. Adhesives include water-based adhesives, organic solvent-based adhesives, solvent-free adhesives, solid adhesives, water-based solvent volatilized adhesives, moisture-curable adhesives, heat-curable adhesives, anaerobic-curable adhesives, active energy ray-curable adhesives, curing agent mixed adhesives, thermomelt adhesives, What is used universally can be used, such as a pressure-sensitive adhesive (adhesive) and a wet type adhesive. Among them, an aqueous solvent volatilized adhesive, an active energy ray curable adhesive, and an adhesive are often used. The thickness of an adhesive layer can be suitably adjusted according to the adhesive force requested | required etc., For example, it is 0.01-500 micrometers, Preferably it is 0.1-300 micrometers. Although two or more adhesive layers may exist in the said laminated body for flexible displays, each thickness and the kind of adhesive agent used may be same or different.

As the aqueous solvent volatilized adhesive, a polymer in a water dispersion state such as a polyvinyl alcohol polymer, a water-soluble polymer such as starch, an ethylene-vinyl acetate emulsion, a styrene-butadiene emulsion, or the like can be used as the main polymer. have. In addition to water and the said main polymer, you may mix | blend a crosslinking agent, a silane compound, an ionic compound, a crosslinking catalyst, antioxidant, dye, a pigment, an inorganic filler, an organic solvent, etc. In the case of adhering with the aqueous solvent volatilized adhesive, the aqueous solvent volatilized adhesive may be injected between the layers to be bonded and bonded to each other, and then the adhesiveness can be imparted by drying. The thickness of the adhesive layer in the case of using the said aqueous solvent volatilization adhesive agent may be 0.01-10 micrometers, Preferably 0.1-1 micrometer may be sufficient. When using the said aqueous solvent volatilization adhesive agent for formation of multiple layers, the thickness of each layer and the kind of said adhesive agent may be same or different.

The said active energy ray hardening-type adhesive agent can be formed by hardening of the active energy ray hardening composition containing the reactive material which irradiates an active energy ray and forms an adhesive bond layer. The active energy ray-curing composition may contain at least one polymer of a radically polymerizable compound and a cationically polymerizable compound similar to the hard coating composition. The said radically polymerizable compound is the same as that of a hard coating composition, The thing of the same kind as a hard coating composition can be used. As a radically polymerizable compound used for an adhesive layer, the compound which has an acryloyl group is preferable. It is also preferable to include a monofunctional compound in order to lower the viscosity as an adhesive composition.

The said cationically polymerizable compound is the same as that of a hard coating composition, The thing of the same kind as a hard coating composition can be used. As a cationically polymerizable compound used for an active energy ray hardening composition, an epoxy compound is especially preferable. It is also preferable to include a monofunctional compound as the reactive diluent in order to lower the viscosity of the adhesive composition.

The active energy ray composition may further include a polymerization initiator. As a polymerization initiator, it is a radical polymerization initiator, a cationic polymerization initiator, a radical, and a cationic polymerization initiator, etc., It can select suitably and can use. These polymerization initiators are decomposed by at least one of active energy ray irradiation and heating to generate radicals or cations to advance radical polymerization and cation polymerization. In the base material of a hard coating composition, the initiator which can start at least any of radical polymerization or cationic polymerization by active energy ray irradiation can be used.

The active energy ray-curing composition may further include an ion trapping agent, an antioxidant, a chain transfer agent, an adhesion agent, a thermoplastic resin, a filler, a fluid viscosity modifier, a plasticizer, an antifoaming agent, an additive, and a solvent. In the case of adhering with the active energy ray-curable adhesive, the active energy ray-curing composition is applied to any one or both of the layers to be bonded and bonded together, and the active energy ray is irradiated by passing through any one of the layers or both layers. It can bond by hardening. The thickness of the adhesive layer in the case of using the said active energy ray hardening-type adhesive agent may be 0.01-20 micrometers, Preferably 0.1-10 micrometers may be sufficient. When using the said active energy ray hardening-type adhesive agent for formation of multiple layers, the thickness of each layer and the kind of adhesive agent used may be same or different.

As the pressure-sensitive adhesive, depending on the main polymer, any of them may be classified into an acrylic pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, a rubber pressure-sensitive adhesive, a silicone pressure-sensitive adhesive, or the like. In addition to a main polymer, you may mix | blend a crosslinking agent, a silane compound, an ionic compound, a crosslinking catalyst, antioxidant, a tackifier, a plasticizer, dye, a pigment, an inorganic filler, etc. to an adhesive. The adhesive layer (adhesive layer) is formed by melt | dissolving and disperse | distributing each component which comprises the said adhesive in a solvent, obtaining an adhesive composition, and apply | coating this adhesive composition on a base material, and drying. The pressure-sensitive adhesive layer may be directly formed or may be transferred to what is formed on a separate substrate. In order to cover the adhesive surface before adhesion, it is also preferable to use a release film. The thickness of the adhesive layer in the case of using the said adhesive is 1-500 micrometers, Preferably it may be 2-300 micrometers. When using the said adhesive for formation of multiple layers, the thickness of each layer and the kind of adhesive used may be same or different.

[Shading Pattern]

The light blocking pattern may be applied as at least a part of the bezel or the housing of the flexible display. The visibility of an image improves by shielding the wiring arrange | positioned at the edge part of the said flexible display by a light shielding pattern, and making it hard to see. The light shielding pattern may be in the form of a single layer or a multilayer. The color of the light shielding pattern is not particularly limited, and may have various colors such as black, white, and metallic color. The light shielding pattern can be formed of a pigment for specifying the color, and a polymer such as an acrylic resin, an ester resin, an epoxy resin, polyurethane, or silicone. It can also be used by these individually or in mixture of 2 or more types. The light shielding pattern may be formed by various methods such as printing, lithography, and inkjet. The thickness of a light shielding pattern is 1-100 micrometers normally, Preferably it is 2-50 micrometers. Moreover, it is also preferable to provide shapes, such as an inclination, in the thickness direction of a light shielding pattern.

EXAMPLE

Hereinafter, the present invention will be described in more detail with reference to Examples. "%" And "part" in an example mean the mass% and a mass part, unless there is particular notice. First, the measuring method of a physical property value is demonstrated.

(Measurement of Weight Average Molecular Weight (Mw))

The measurement was performed using gel permeation chromatography (GPC). The preparation method and measurement conditions of a measurement sample are as follows.

(1) Sample preparation method

20 mg of the resin was measured and 10 mL of DMF (10 mmol / L lithium bromide) was added and completely dissolved. This solution was filtered through a chromatographic disc (pore diameter 0.45 mu m) to obtain a sample solution.

(2) measurement conditions

Device: HLC-8020GPC

Column: Guard column + TSKgelα-M (300 mm x 7.8 mm diameter) x 2 + α-2500 (300 mm x 7.8 mm diameter) x 1

Eluent: DMF (with 10 mmol / L lithium bromide)

Flow rate: 1.0 mL / min

Detector: RI Detector

Column temperature: 40 ℃

Injection volume: 100 μL

Molecular Weight Standard: Standard Polystyrene

(Wide angle X-ray diffraction measurement)

The polyimide resin powder was laid on the glass sample plate so that the sample top surface was flat, a measurement sample was prepared, and wide-angle X-ray diffraction was measured under the following measurement conditions. In the obtained measurement result, the presence or absence of the diffraction peak derived from crystalline was confirmed, and it was confirmed that the resin powder is amorphous by not detecting the peak.

<Measurement condition>

X-ray diffractometer: X 'Pert PRO MPD (made by Spectress Co., Ltd.)

Voltage: 45 ㎸

Current: 40 mA

Measuring range: 2θ = 5 to 90 °

(Specific surface area)

Using BELPREP-vacII (manufactured by Microtrack Bell Co., Ltd.) as a pretreatment apparatus, the polyimide resin powder was pretreated under vacuum conditions at 120 ° C. for 8 hours to prepare a measurement sample. About such a measurement sample, adsorption isotherm was measured using the normal method and the specific surface area was computed by the BET method.

<Measurement condition>

Measuring device: BELSORP-Max (manufactured by Microtrack Bell Co., Ltd.)

Adsorption Temperature: 77 K

Adsorbate: Kr

Saturated vapor pressure: 0.3320 kPa

Adsorbate Cross Section: 0.2020 nm ²

Equilibrium wait time: The pressure change over 500 seconds is within 0.2% of the reading of the pressure gauge.

Number of measurements: N = 1

Repose angle

Using powder tester PT-X (manufactured by Hosokawa Micron Co., Ltd.) as a measuring device, the polyimide resin powder was dropped from a funnel of a constant height onto a horizontal substrate, and the angle of the resulting deposit was measured to be referred to as an angle of repose.

(Tap density)

The polyimide resin powder was put in a 20 mL mass cylinder and tapped for 3 minutes. The mass (g) of the powder was divided by the volume (cm 3) after tapping to calculate the tap density (g / cm 3).

(Color)

What put the polyimide resin powder into the chalet as a measurement sample, and uses chromatic color difference meter "CR-5" made by Konica Minolta Co., Ltd., and is based on chromaticity (JIS Z 8781-4: 2013) under the following measurement conditions. ) Was measured.

<Measurement condition>

Observation conditions: 2 ° field of view (CIE1931)

Observation light source: C

Color system: L ^* a ^* b ^* color space

Color difference formula: ΔE ^* ab (CIE1976) color difference formula

Index: none

Measurement Type: Chalet Measurement

Measurement diameter φ: 30 mm

(Particle size distribution)

Using the polyimide resin powder as a measurement sample, particle size distribution was measured under the following measurement conditions using a micro track particle size analyzer MT-3100II (manufactured by Nikiso Corporation).

<Measurement condition>

Particle Refractive Index: 1.53

Measurement Method: Dry Laser Diffraction

[Confirmation of Solubility of Resin in Solvent]

The resin powder of the composition similar to the manufacture example 1 was prepared, and the solubility to the solvent was confirmed by the following method.

9.9 g of a solvent was measured and taken in a 30 mL glass screw tube, and a magnetic stirrer was further added and stirred. 0.1g of the said resin powder was added there, it stirred at room temperature (24 degreeC) for 3 hours, and the solubility was confirmed.

As a result, the resin powder was dissolved in DMAc but not in methanol and ion-exchanged water. Therefore, DMAc is a good solvent and methanol and ion-exchanged water are poor solvents. In addition, in the external appearance during stirring, the resin powder was in a state of being suspended in methanol, but did not enter the water and remained on the water surface. From this, methanol and water are compared, and it is estimated that the water is high in the poor solvent.

(Flexibility test)

The optical film obtained by the Example and the comparative example was cut into the magnitude | size of 10 mm x 100 mm using the dumbbell cutter. The cut film is placed in an MIT anti-fatigue fatigue tester ("MIT-DA" model manufactured by Toyo Seiki Co., Ltd. model: 0530), the test speed of 175 cpm, bending angle 135 °, load 0.75 kg, R of bending clamp = Under the conditions of 1.0 mm, bending tests in both front and back directions were performed, and the number of times of bending resistance (the number of times that can be bent without breaking) of each film was measured.

Production Example 1: Preparation of Polyimide Resin 1

Nitrogen was conducted to the reaction vessel provided with the stirrer and thermometer sufficiently dried, and the inside of the vessel was replaced with nitrogen. The reaction vessel was cooled to 10 ° C., 1567.4 kg of DMAc was placed in the vessel, 91.8 kg of 2,2′-bis (trifluoromethyl) benzidine (TFMB) and 4,4 ′-(hexafluoroisopropylidene) 38.6 kg of diphthalic anhydride (6FDA) was added, and it stirred for 3 hours.

Subsequently, 4.3 kg of 4,4'-oxybis (benzoyl chloride) (OBBC) and 15.9 kg of terephthaloyl chloride (TPC) were added, stirred for 30 minutes, the same amount of OBBC and TPC were added, and stirred for the same time. . 1567.4 kg of DMAc and 3.5 kg of TPC were added to the resulting reaction solution, and further stirred at 10 ° C. for 2 hours.

Subsequently, 26.2 kg of diisopropylethylamine and 62.1 kg of acetic anhydride were added and stirred for 30 minutes while maintaining at 10 ° C., then 18.9 kg of 4-picoline was added, and the reaction vessel was heated to 75 ° C. and further added. It stirred for 3 hours, and obtained the reaction liquid.

The reaction solution was cooled and 940.4 kg of methanol was added at the point where the temperature was lowered to 40 ° C. or lower. The reaction liquid thus obtained is referred to as reaction liquid (1) below. At this stage, the reaction solution (1) was transparent and no precipitation of particles occurred.

Production Example 2: Preparation of Polyimide Resin 2

Nitrogen was conducted to the reaction vessel provided with the stirrer and thermometer dried sufficiently, and the inside of the vessel was replaced with nitrogen. In the reaction vessel, 512.29 g of DMAc and 30.00 g (93.68 mmol) of TFMB were added, and TFMB was dissolved in DMAc while stirring at room temperature. Next, 12.61 g (28.39 mmol) of 6FDA and 2.78 g (9.46 mmol) of 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride (BPDA) were added followed by 11.53 g (56.78 mmol) of TPC. And it stirred at room temperature for 1 hour.

Subsequently, 5.29 g (56.78 mmol) of 4-picoline and 27.05 g (264.95 mmol) of acetic anhydride were added to the flask, followed by stirring at room temperature for 30 minutes, and then the reaction vessel was heated to 70 DEG C, further stirred for 3 hours. And the reaction liquid was obtained.

The reaction solution was cooled, and 307.36 g of methanol was added at the point where the temperature was lowered to 40 ° C. or lower. The reaction liquid thus obtained is referred to as reaction liquid (2) below. At this stage, the reaction solution (2) was transparent and no precipitation of particles occurred.

Example 1: Preparation of Polyimide Resin Powder 1

Nitrogen was conducted to the reaction vessel provided with the stirrer and the thermometer, and the inside of the vessel was replaced with nitrogen. 1452.2 kg of the reaction solution (1) was placed in a reaction vessel with stirring at 20 ° C. Subsequently, 1253.9 kg of methanol was added dropwise as a first poor solvent at a rate of 30 kg / min, and then 783.7 kg of ion-exchanged water was dropped as a second poor solvent at a rate of 7 kg / min to precipitate a white solid. The precipitated white solid was collected by centrifugal filtration and washed with methanol to obtain a wet cake containing polyimide resin. 52 kg of polyimide resin powders 1 were obtained by drying the obtained wet cake at 78 degreeC under reduced pressure.

The result of each measurement with respect to the obtained polyimide resin powder 1 is shown below.

Weight average molecular weight (Mw): 343,000

Wide angle X-ray diffraction: amorphous

BET specific surface area: 0.22 m 2 / g

Tap density: 0.41 g / cm 3

Repose angle: 37.8 °

Chromaticity (L ^* a ^* b ^* Colorimetric System): L ^* = 98.22, a ^{* =} -2.29, b ^* = 6.56

Particle size distribution: d ₁₀ = 152 µm, d ₅₀ = 205 µm, d ₉₀ = 264 µm

The polyimide resin powder 1 produced above was dissolved in DMAc to obtain a polyimide solution having a resin concentration of 10% by mass. The obtained polyimide solution was applied on the smooth surface of the polyester base material (Toyobo Co., Ltd., brand name "A4100") using an applicator so that the thickness of a self-supporting film might be 55 micrometers, and then it was 140 degreeC at 50 degreeC for 30 minutes. After drying for 15 minutes at, the obtained coating film was peeled from the polyester substrate to obtain a freestanding film. The self-supporting film was fixed to a metal mold, and further dried at 200 ° C. for 40 minutes in the air to obtain a polyimide resin film 1 having a thickness of 50 μm.

The bending resistance test of the obtained polyimide-based resin film 1 was carried out, and the number of bending resistance was more than 100,000 times.

Example 2: Preparation of Polyimide Resin Powder 2

Nitrogen was conducted to the reaction vessel provided with the stirrer and the thermometer, and the inside of the vessel was replaced with nitrogen. 0.500 kg of the reaction liquid (2) was placed in a reaction vessel with stirring at 20 ° C. Next, 0.432 kg of methanol was added dropwise as a first poor solvent at a rate of 0.04 kg / min, and 0.270 kg of ion-exchanged water was dropped as a second poor solvent at a rate of 0.014 kg / min to precipitate a white solid. The wet white cake containing the polyimide-type resin was obtained by collecting the precipitated white solid by vacuum filtration and wash | cleaning with methanol. The obtained wet cake was dried at 78 degreeC under reduced pressure, and 0.031 kg of polyimide-type resin powder 2 was obtained.

The result of each measurement with respect to the obtained polyimide resin powder 2 is shown below.

Weight average molecular weight (Mw): 340,000

Wide angle X-ray diffraction: amorphous

BET specific surface area: 1.33 ㎡ / g

Chromaticity (L ^* a ^* b ^* Colorimetric System): L ^* = 99.61, a ^* = -2.04, b ^* = 4.95

A polyimide resin film 2 having a thickness of 50 μm was obtained by the same method except that the polyimide resin powder 2 obtained above was used.

The bending resistance test of the obtained polyimide-type resin film 2 was performed, and the frequency | count of bending resistance was more than 100,000 times.

(Evaluation of handleability and solubility in a solvent)

190 g of GBL was added to a 500 mL glass beaker and stirred with a stirrer. 10 g of the powders obtained in Examples 1 and 2 were respectively measured by taking a cup made of polyethylene. Next, the measured and taken powder was poured from the cup into the glass beaker containing the solvent. The handleability at the time of pouring powder and the solubility to the solvent after pouring were evaluated based on the following reference | standard. The powder produced in Example 1 and Example 2 was able to flow cleanly, and there was no generation | occurrence | production of a lump. Moreover, when stirred for 1 hour, the colorless and transparent solution was obtained. Therefore, both the handleability and the solubility to a solvent were evaluation of (circle) in the following evaluation criteria, and it was confirmed that handleability and solubility are favorable.

<Handling>

(Circle): The powder was able to be poured cleanly, and no lump was generated.

X: The powder could not be poured neatly, and lumps arose.

Solubility in solvent

(Circle): Powder melt | dissolves in a solvent and the colorless and transparent solution is obtained.

X: The powder is not dissolved in the solvent.

Comparative Example 1

Nitrogen was conducted to the reaction vessel provided with the stirrer and the thermometer, and the inside of the vessel was replaced with nitrogen. While stirring at 20 degreeC, 1,452.2 kg of reaction liquids (1) obtained by the manufacture example 1 were put into the reaction container. Next, 1253.9 kg of methanol was dripped as a 1st poor solvent from the nozzle (inner diameter: 22 mm) at the speed of 30 kg / min. From the middle of the dropping, the solution began to become cloudy.

Next, 783.7 kg of methanol was dripped further at the speed | rate of 7 kg / min from a nozzle (inner diameter: 22 mm). As the dropping proceeded, the degree of clouding of the solution became stronger.

The precipitated white solid was collected by centrifugal filtration and washed with methanol to obtain a rubbery mixture containing a polyamideimide resin. Although the coloring of the obtained mixture was not seen, it was rubbery, the fixation to the follicle was confirmed, and it was not able to collect | recover as powder.

Claims (9)

An amorphous polyimide resin powder having a specific surface area of 10 m 2 / g or less and a weight average molecular weight of 100,000 or more. The method of claim 1,
Polyimide-type resin powder whose repose angle is 45 degrees or less. The method of claim 1,
Polyimide resin powder whose tap density is 0.3-0.6 g / cm <3>. The method of claim 1,
In the L ^* a ^* b ^* color difference measurement based on the color ^{space, L * ≥90, -10≤a * ≤10} , and polyimide resin powder satisfying the -10≤b ^* ≤10. As a manufacturing method of the polyimide resin powder in any one of Claims 1-4,
Contacting the solution in which the polyimide resin is dissolved in the good solvent with at least two poor solvents for the polyimide resin, and contacting the solution of the polyimide resin with the first poor solvent, and And the process of adding a 2nd poor solvent to the solution obtained at the said process. The optical film formed using the polyimide resin powder in any one of Claims 1-4. The flexible display provided with the optical film of Claim 6. The method of claim 7, wherein
A flexible display, further comprising a touch sensor. The method of claim 7, wherein
A flexible display, further comprising a polarizing plate.