KR20210123333A - Method for producing polyimide-based resin powder - Google Patents

Abstract

The manufacturing method of polyimide-type resin powder which can efficiently remove alcoholic solvents, such as methanol, when manufacturing polyimide-type resin powder is provided.
(1) A polyimide-based resin solution in which a polyimide-based resin is dissolved in a good solvent is brought into contact with a solvent containing an alcohol having 1 to 4 carbon atoms to precipitate a polyimide-based resin, and the precipitated polyimide-based resin is included the process of obtaining a mixture,
(2) solid-liquid separation of the obtained mixture, the process of obtaining the polyimide-type resin composition (a) containing the polyimide-type resin which precipitated, and;
(3) The manufacturing method of polyimide-type resin powder including the process of making polyimide-type resin composition (a) contact with the solvent which has water as a main component at least.

Description

Method for producing polyimide-based resin powder

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

BACKGROUND ART At present, image display devices such as liquid crystal display devices and organic EL display devices are widely utilized not only for televisions but also for various uses such as cellular phones and smart watches. With the expansion of such a 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 retardation plate, and a front plate, other than display elements, such as a liquid crystal display element or an organic electroluminescent display element. In order to achieve a flexible display, all these constituent members need to have flexibility.

Until now, glass has been used as the front plate. While glass has high transparency and can express high hardness depending on the type of glass, it is very rigid and brittle, so it is difficult to use it as a front plate material for a flexible display.

Therefore, the utilization of a polymer material as a material instead of glass is examined. Since the front plate made of a polymer material easily exhibits flexible properties, it can be expected to be used in various applications. Although various resins are mentioned as resin which has flexibility, For example, there exists a polyimide-type resin.

When using a polyimide-based resin to produce a polymer material such as a film, for example, from the viewpoint of reducing the volume during transport, the polyimide-based resin is prepared as a powder, and the powder is transported to the film formation site. , film-forming is performed using the varnish of the polyimide-type resin prepared using the said powder.

As a manufacturing method of the powder of such a polyimide-type resin, methanol, ethanol, etc. are added to the solution containing a polyimide-type resin, and making the powder of a polyimide-type resin precipitate (for example, patent document 1) ). However, as also described in paragraph [0030] of Patent Document 1, when a poor solvent having a hydroxyl group such as methanol is used, the polyimide-based resin powder containing the poor solvent is dried, and a film obtained using the powder is used. In some cases, problems such as a decrease in heat resistance and/or coloration of the film may occur. For example, in patent document 1, in order to avoid the fall of heat resistance and coloring as mentioned above, drying over a long period of time at the temperature of less than 100 degreeC until the volatile component in polyimide powder becomes about less than 5% is described. has been

International Publication No. 2017/179367

An object of this invention is to provide the manufacturing method of polyimide-type resin powder which can efficiently remove alcohol-type solvent, such as methanol, when manufacturing polyimide-type resin powder under said background art.

MEANS TO SOLVE THE PROBLEM This inventor earnestly examined, paying attention to the manufacturing conditions of polyimide-type resin powder, in order to solve the said subject. As a result, a polyimide-based resin is precipitated with a predetermined solvent, and the polyimide-based resin composition containing the precipitated polyimide-based resin is brought into contact with a solvent containing water as a main component. It found that the said subject was solved, and came to complete this invention.

That is, the present invention includes the following suitable aspects.

[1] (1) A polyimide-based resin solution in which a polyimide-based resin is dissolved in a good solvent is brought into contact with a solvent containing an alcohol having 1 to 4 carbon atoms to precipitate a polyimide-based resin, and the precipitated polyimide-based resin A process for obtaining a mixture comprising

(2) solid-liquid separation of the obtained mixture, the process of obtaining the polyimide-type resin composition (a) containing the polyimide-type resin which precipitated, and;

(3) The step of bringing the polyimide-based resin composition (a) into contact with a solvent containing water as a main component

A method for producing a polyimide-based resin powder comprising at least a.

[2] The chromaticity of the polyimide-based resin powder satisfies L*≥90, -10≤a*≤10, and -10≤b*≤10 in the color difference measurement based on the L*a*b* color system. , the production method according to [1] above.

[3] The production method according to [1] or [2], wherein the polyimide-based resin contains a fluorine atom.

[4] The production method according to any one of [1] to [3], wherein the polyimide-based resin is an aromatic polyimide-based resin.

[5] The production method according to any one of [1] to [4], wherein the polyimide-based resin has an imidization ratio of 90% or more.

According to [6] Step (3), a polyimide-based resin composition (a) by weight as the W ₁ is called, and the mass of the solvent composed mainly of water is brought into contact with the art polyimide based resin composition (a) W ₂ of If the ratio of W ₂ to _{W 1 (W 2 / W 1} ) is 4 or more, the contact time process according to any of 10 minutes or more, the [1] to [5].

[7] After step (3),

(4) The production method according to any one of [1] to [6], including a step of performing solid-liquid separation to obtain a polyimide-based resin composition (b).

[8] The content of water in the polyimide-based resin composition (b) is 10% by mass or more with respect to the total mass of the polyimide-based resin composition, and the content of the alcohol having 1 to 4 carbon atoms is The manufacturing method as described in said [7] which is less than 3 mass % with respect to the total mass of a mid-type resin composition (b).

[9] Before the step (2), the above [ The manufacturing method according to any one of 1] to [8].

[10] Before the step (3), the above [1] to [ 9] The manufacturing method according to any one of.

[11] A polyimide-based resin composition comprising at least a polyimide-based resin and water, wherein the content of water in the polyimide-based resin composition is 10% by mass or more with respect to the total mass of the polyimide-based resin composition; Moreover, content of a C1-C4 alcohol is less than 3 mass % with respect to the total mass of the said polyimide-type resin composition, The polyimide-type resin composition.

[12] The polyimide-based resin composition according to [11], wherein the content of the alcohol having 1 to 4 carbon atoms is 0.001% by mass or more with respect to the total mass of the polyimide-based resin composition.

ADVANTAGE OF THE INVENTION According to this invention, when manufacturing polyimide-type resin powder, it is possible to provide the manufacturing method of polyimide-type resin powder which can efficiently remove poor solvents, such as methanol.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail. In addition, the scope of the present invention is not limited to the embodiments described herein, and various changes can be made without departing from the spirit of the present invention.

The manufacturing method of the polyimide-type resin powder of this invention (hereafter also referred to as "the manufacturing method of this invention"),

(1) A polyimide-based resin solution in which a polyimide-based resin is dissolved in a good solvent is brought into contact with a solvent containing an alcohol having 1 to 4 carbon atoms to precipitate a polyimide-based resin, and the precipitated polyimide-based resin is included the process of obtaining a mixture,

(2) solid-liquid separation of the obtained mixture, the process of obtaining the polyimide-type resin composition (a) containing the polyimide-type resin which precipitated, and;

(3) The process of making the said polyimide-type resin composition (a) contact with the solvent which has water as a main component

includes at least

<Process (1)>

In the method for producing a polyimide-based resin powder of the present invention, a polyimide-based resin solution in which the polyimide-based resin is dissolved in a good solvent is brought into contact with a solvent containing an alcohol having 1 to 4 carbon atoms to precipitate the polyimide-based resin, , the step (1) of obtaining a mixture containing the deposited polyimide-based resin is included at least.

(Polyimide-based resin solution)

The polyimide-type resin solution made to contact with the solvent containing C1-C4 alcohol in the process (1) is the solution which the polyimide-type resin melt|dissolved in the good solvent. Here, in this specification, polyimide-type resin shows at least 1 sort(s) of resin chosen from the group which consists of polyimide resin, polyamideimide resin, polyimide precursor resin, and polyamideimide precursor resin. The polyimide resin is a resin containing a repeating structural unit containing an imide group, and the polyamideimide resin is a resin containing a repeating structural unit containing both an imide group and an amide group. In addition, polyimide precursor resin and polyamide-imide precursor resin are precursors before imidation which provide a polyimide resin and polyamide-imide resin by imidation, respectively, and are resin also called polyamic acid. In this specification, the said polyimide precursor resin and the said polyamide-imide precursor resin are put together, and "polyamic acid resin" is also called.

The polyimide-based resin solution may be a reaction solution obtained by polymerizing the raw material monomer of the polyimide-based resin in a solvent, especially in a good solvent for the polyimide-based resin, or an isolated polyimide-based resin as a good solvent. A solution obtained by dissolving in From the viewpoint of easily carrying out the process from the synthesis of the polyimide-based resin to the production of the polyimide-based resin powder efficiently, the polymerization reaction of the monomers is performed in a good solvent to be described later, and the obtained reaction solution is used as a polyimide-based resin solution. It is preferable to use

The good solvent contained in the polyimide-based resin solution is a solvent in which the polyimide-based resin is easily dissolved, for example, a solvent having a solubility in the polyimide-based resin at room temperature (20 to 30°C) of 1 mass % or more. 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). can In addition, whether the solvent to be used is a good solvent can be confirmed by the following method. Polyimide-based resin is added to the solvent so that it becomes 1% by mass, and if necessary, the resin is dissolved in the solvent by heating and stirring, etc., and if the solution at room temperature (20 to 30° C.) is uniformly transparent, the solvent is If it is a good solvent and the solution does not become uniformly transparent, the solvent is not a good solvent but a poor solvent. For example, in the present Example, the solvent was measured and taken in a container, stirred, polyimide-type resin was put there so that it might become 1 mass %, and it stirred at room temperature (24 degreeC) for 3 hours. As a result, when there is no dissolved substance and the solution is uniformly transparent, it is a good solvent, and when a dissolved substance exists, it can be judged not as a good solvent but as a poor solvent.

The solubility with respect to the polyimide-type resin of a good solvent becomes like this. From a viewpoint of volume efficiency, Preferably it is 3 mass % or more, More preferably, it is 5 mass % or more. Although the upper limit of the solubility with respect to the polyimide-type resin of a good solvent is not specifically limited, From a viewpoint which can reduce the usage-amount of a poor solvent, Preferably it is 40 mass % or less, More preferably, it is 25 mass % or less. In addition, in this specification, the solubility with respect to the polyimide-type resin of a certain solvent A, when the quantity of the polyimide-type resin soluble in X mass parts of solvent A is Y mass parts, solubility (%)=Y/(X+) It is a value calculated by the formula of Y) x 100.

Preferably content of the good solvent in a polyimide-type resin solution is 60 mass % or more with respect to the total amount of a polyimide-type resin solution from a viewpoint of being easy to adjust to the viscosity which is easy to handle on operation, More preferably, 75 mass % or more. Further, the content of the good solvent in the polyimide-based resin solution is preferably 98% by mass or less, more preferably 95% by mass, based on the total amount of the poly2-based resin solution, from the viewpoint of reducing the amount of the poor solvent used. % or less.

Preferably content of the polyimide-type resin in a polyimide-type resin solution is 1 mass % or more with respect to the total amount of a polyimide-type resin solution from a volume efficiency viewpoint, More preferably, it is 3 mass % or more. In addition, the content of the polyimide-based resin in the polyimide-based resin solution is preferably 20% by mass or less with respect to the total amount of the polyimide-based resin solution, from the viewpoint of being easy to adjust to a viscosity that is easy to handle in terms of operation, more Preferably it is 10 mass % or less.

(Solvent containing alcohol having 1 to 4 carbon atoms)

In the process (1), said polyimide-type resin solution and the solvent containing a C1-C4 alcohol are made to contact, and polyimide-type resin is precipitated. The solvent containing a C1-C4 alcohol is a poor solvent with respect to polyimide-type resin. Examples of the alcohol having 1 to 4 carbon atoms include methanol, ethanol, 2-propanol and butanol.

It is preferable that the solvent containing a C1-C4 alcohol is a solvent which has a C1-C4 alcohol as a main component. In this specification, using as a main component means that it occupies 70 mass % or more. By using a solvent containing an alcohol of 1 to 4 carbon atoms, preferably a solvent containing an alcohol having 1 to 4 carbon atoms as a main component, as a poor solvent, it is easy to effectively precipitate the polyimide-based resin. The ratio of the alcohol of 1 to 4 carbon atoms in the solvent containing the alcohol having 1 to 4 carbon atoms is preferably 50 mass% or more, more preferably 60 mass% or more, from the viewpoint of easy precipitation of the polyimide-based resin. , more preferably 70 mass % or more, still more preferably 75 mass % or more, particularly preferably 80 mass % or more, particularly more preferably 85 mass % or more, particularly more preferably 90 mass % or more. In the step (1), the solvent to be brought into contact with the polyimide-based resin may be one type of alcohol having 1 to 4 carbon atoms, or a mixture of two or more types of alcohols having 1 to 4 carbon atoms, or one type or two or more types of alcohols having 1 or more carbon atoms. A mixture of the alcohol of -4 and another solvent may be sufficient. In this specification, "a solvent containing a C1-C4 alcohol" is also called an "alcoholic solvent."

By making a polyimide-type resin solution and an alcohol-type solvent contact, polyimide-type resin precipitates, and the mixture containing the polyimide-type resin which precipitated is obtained. When the polyimide-based resin solution in which the polyimide-based resin is dissolved in a good solvent is brought into contact with a solvent containing an alcohol having 1 to 4 carbon atoms, the solubility of the polyimide-based resin as a whole solvent decreases, so that it cannot be completely dissolved. polyimide-based resin is precipitated. The method of bringing the polyimide-based resin solution into contact with the alcohol-based solvent is not particularly limited as long as they are in contact. For example, a method of adding an alcohol-based solvent to the polyimide-based resin solution or polyimide to an alcohol-based solvent The method of adding a mid-type resin solution is mentioned. From a viewpoint of easy obtaining of powder, it is preferable to perform contact of a polyimide-type resin solution and an alcohol-type solvent by adding an alcohol-type solvent to a polyimide-type resin solution. Moreover, from a viewpoint of being easy to adjust an addition rate, it is more preferable to perform addition by dripping. By the said contact, polyimide-type resin precipitates, and the mixture containing the polyimide-type resin which precipitated is obtained. Moreover, the mixture containing the polyimide-type resin which precipitated WHEREIN: The polyimide-type resin of at least one part of the polyimide-type resin melt|dissolved in the polyimide-type resin solution should just deposit.

When the polyimide-based resin solution is contacted by a method of adding an alcohol-based solvent, the addition method also follows, but immediately after the addition, a portion with a high concentration of the alcohol-based solvent is locally generated, and then the entire polyimide-based resin solution spread to When the concentration of the alcohol-based solvent is too high locally, the polyimide-based resin powder is rapidly precipitated locally, and impurities are easily mixed into the polyimide-based resin powder, or the solidified polyimide-based resin contains a solvent. By doing so, it may become difficult to obtain powder. Therefore, it is preferable to select an addition method and an addition rate so that local precipitation may not arise as much as possible, from a viewpoint of easy precipitation of polyimide-type resin powder efficiently and high precision. From the viewpoint of suppressing the local precipitation of the polyimide resin powder, a method capable of suppressing the local concentration increase of the alcohol solvent is preferable, and from the viewpoint of easily increasing the production efficiency of the polyimide resin powder, the alcohol solvent A method capable of increasing the rate of addition is preferred. From this point of view, as a preferable method of adding an alcohol-based solvent to the polyimide-based resin solution, for example, using a plurality of nozzles or a nozzle having a plurality of branches, a method of dividing the addition by line, or adding using a shower nozzle method, a dip method in which addition is performed while the outlet of the alcohol solvent is immersed in a polyimide-based resin solution, and a method of attaching a dispersion plate to the tip of a nozzle, and the like.

In the step (1), the amount of the polyimide-based resin in the polyimide-based resin solution is M parts by mass, and the amount of the good solvent is N parts by mass, and in the step (1), the alcohol-based polyimide-based resin solution is brought into contact with the polyimide-based resin solution. When the amount of the solvent is Z mass parts, the mass ratio of each component is the relational formulas (i) and (ii):

5≤N/M≤40 (i)

20≤Z/M≤100 (ii)

It is desirable to satisfy

N/M in Formula (i) shows the relationship between the quantity of the good solvent in a polyimide-type resin solution, and the quantity of polyimide-type resin. In addition, when using 2 or more types of solvent as a good solvent, let the total mass be N. N/M is preferably 5 or more, more preferably 10 or more, still more preferably 15 or more from the viewpoint of dissolving the polyimide-based resin in the polyimide-based resin solution and adjusting the viscosity to an easy-to-handle viscosity. . N/M is preferably 40 or less, more preferably 35 or less, more from the viewpoint of easy precipitation of the polyimide-based resin in the step of precipitating the polyimide-based resin by adding an alcohol-based solvent and an aqueous solvent Preferably it is 30 or less.

Z/M in formula (ii) shows the relationship between the quantity of the polyimide-type resin in a polyimide-type resin solution, a polyimide-type resin solution, and the quantity of the alcohol-type solvent made to contact in a process (1). In addition, when using 2 or more types of solvent as an alcohol solvent, let the total mass be Z<_1> . Z/M is preferably 20 or more, more preferably 25 or more, still more preferably 30 or more from the viewpoint of easy precipitation of the polyimide-based resin as powder. From the viewpoint of reducing the amount of waste liquid, Z/M is preferably 90 or less, more preferably 85 or less, and still more preferably 80 or less.

<Process (X)>

The manufacturing method of this invention may further include the process (X) of making the mixture obtained in the process (1) contact the solvent containing water, before the process (2) following the process (1). By performing a process (X) subsequent to a process (1), it is easy to suppress that the polyimide-type resin powder which precipitates mutually welds. As a result, it becomes easy to manufacture polyimide-type resin powder efficiently. It is preferable that the solvent containing water is a solvent which has water as a main component. By performing the process (X) of making contact with the solvent containing water, preferably the solvent which has water as a main component, welding of polyimide-type resin powder is prevented and it becomes easy to precipitate. The amount of water in the solvent containing water to be brought into contact in the step (X) is preferably 50 mass from the viewpoint of easily reducing the amount of the good solvent and the alcohol having 1 to 4 carbon atoms contained in the precipitated polyimide-based resin powder. % or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, even more preferably 75% by mass or more, particularly preferably 80% by mass or more, particularly more preferably 85% by mass or more, More preferably, it is 90 mass % or more. In this specification, "a solvent containing water" is also called "aqueous solvent."

In one preferable embodiment of the manufacturing method of this invention containing a process (1) and a process (X), in the contact process with the solvent containing a C1-C4 alcohol (process (1)), a polyimide is necessarily It is not necessary for the system resin to precipitate, and in the step of contacting with a solvent containing water (step (X)), at least a part of the polyimide-based resin dissolved in the polyimide-based resin solution is powdered. It should be precipitated as Therefore, when step (X) is performed following step (1), these steps are combined, step (1X): a polyimide-based resin solution in which the polyimide-based resin is dissolved in a good solvent, and an alcohol having 1 to 4 carbon atoms It is good also as the process of contacting the solvent containing contained to obtain a mixture, then contacting the said mixture and the solvent containing water to precipitate a polyimide-type resin, and obtaining the mixture containing the polyimide-type resin which precipitated.

In the step (X), the method of bringing the mixture obtained in the step (1) into contact with the solvent containing water is also not particularly limited, and the contacting method described above with respect to the step (1) may be used similarly. From a viewpoint of easy precipitation of polyimide-type resin powder, it is preferable to perform contact of the mixture obtained in the process (1), and the solvent containing water by adding the solvent containing water to the said mixture.

In one preferred embodiment of the manufacturing method of the present invention, the polyimide-based resin solution is brought into contact with the alcohol-based solvent in the step (1) and then brought into contact with the aqueous solvent in the step (X). The amount of the polyimide-based resin in the solution is M parts by mass, and the amount of the good solvent is N parts by mass, and the amount of the alcohol-based solvent to be brought into contact with the polyimide-based resin solution in the step (1) is Z ₁ part by mass, the step ( When the amount of the solvent containing water to be brought into contact in X) is Z ₂ parts by mass, the mass ratio of each component is the relational formulas (i), (iii) and (iv):

5≤N/M≤40 (i)

10≤Z ₁ /M≤50 (iii)

3≤Z ₂ /M≤30 (iv)

It is desirable to satisfy

N/M in formula (i) is as described above with respect to process (1).

_{Z 1} /M in formula (iii) shows the relationship between the quantity of the polyimide-type resin in a polyimide-type resin solution, a polyimide-type resin solution, and the quantity of the alcohol-type solvent made to contact in a process (1). In addition, when using 2 or more types of solvent as an alcohol solvent, let the total mass be Z<_1> . Z ₁ /M is preferably 10 or more, more preferably 15 or more, still more preferably 20 or more from the viewpoint of easily suppressing a sudden change in solubility of the polyimide-based resin in the subsequent step (X). . Z ₁ /M is preferably 50 or less from the viewpoint of preventing excessive precipitation of the polyimide-based resin in the step (1) and precipitating the polyimide-based resin as a powder accurately in the step (2). , more preferably 40 or less, still more preferably 35 or less.

Equation (iv) Z ₂ / M is in the, shows the relation between the water-based solvent is brought into contact in the volume, step (X) of the polyimide-based resin, polyimide-based resin in the solution. In addition, when using the solvent of two or more as the water-based solvent to the total mass to Z _2. Z ₂ /M is preferably 3 or more, more preferably 5 or more, still more preferably 8 or more from the viewpoint of easily precipitating polyimide-based resin as powder. Z ₂ /M is preferably 30 or less, more preferably 25 or less, still more preferably 22 or less from the viewpoint of easily relaxing the conditions for drying the powder and reducing the amount of waste liquid.

<Process (2)>

Next, in the step (2), the mixture obtained in the step (1) or the mixture obtained through the steps (1) and (X) is subjected to solid-liquid separation to obtain the precipitated polyimide-based resin contained in the mixture. The polyimide-type resin composition containing is obtained. In addition, in the step (2), when the mixture obtained in the step (1) is solid-liquid separated, the polyimide-based resin contained in the mixture and a part of the solvent contained in the mixture are included. A resin composition can be obtained. The said polyimide-type resin composition is a composition also called a wet cake, and is an intermediate body for obtaining polyimide-type resin powder. In this specification, the polyimide-type resin composition obtained in process (2) is called "polyimide-type resin composition (a)."

The method of solid-liquid separation is not particularly limited, and for example, a method generally called filtration, specifically, a method of separating by gravity through a filter having different permeability of a precipitate and a solvent, and a method of separating by centrifugal force , a method of separating by a pressure difference is mentioned. A centrifugal filter, a Drew filter filter, a suction filter, a vacuum filter, etc. are mentioned as an example of a filter which can be used. The polyimide-based resin composition (a) thus obtained contains the deposited polyimide-based resin powder, a good solvent, and an alcohol having 1 to 4 carbon atoms derived from the alcohol-based solvent brought into contact with the step (1). Although it is also possible to obtain polyimide-type resin powder by drying a polyimide-type resin composition (a), the polyimide-type resin composition (a) contains a comparatively large amount of alcohol. Therefore, problems such as a decrease in the heat resistance of the film and/or coloring of the film cannot be avoided simply by drying the polyimide-based resin composition (a), for example, as described in Patent Document 1 , until the content of volatile components such as alcohol is, for example, less than about 5%, it is necessary to dry at a low temperature over time, which tends to decrease the production efficiency. In the manufacturing method of this invention, polyimide-type resin powder can be manufactured by drying the polyimide-type resin composition (b) obtained through the process (3) mentioned later. In a polyimide-type resin composition (b), since content of components, such as alcohol, has already become low, it is hard to produce the above problems.

<Process (3)>

In the manufacturing method of this invention, the process of making a polyimide-type resin composition contact with the solvent which has water as a main component is further included. The polyimide-based resin composition (a) obtained in the step (2) or the polyimide-based resin composition (a′) obtained through the step (2) and the later-described step (Y) is brought into contact with a solvent containing water as a main component By doing so, the alcohol concentration contained in the polyimide-type resin composition (a) with the polyimide-type resin which precipitated can be reduced efficiently. Hereinafter, although a polyimide-type resin composition (a) is demonstrated, the polyimide-type resin composition (a') mentioned later may be sufficient as a polyimide-type resin composition (a). Although the method of making contact with the solvent which has water as a main component is not specifically limited, For example, you may add and contact with the solvent which has water as a main component to the polyimide-type resin composition (a), The polyimide-type resin composition (a) ) and a solvent containing water as a main component may be mixed and brought into contact. Thereby, the alcohol contained in a polyimide-type resin composition (a) is diluted, and/or the polyimide-type resin powder contained in a polyimide-type resin composition (a) is wash|cleaned. By performing such operation, the mixture containing at least the polyimide-type resin and aqueous solvent which precipitated is obtained.

"The solvent which has water as a main component" used in the process (3) means the solvent containing 70 mass % or more of water with respect to the said whole solvent. The ratio of water in the solvent is preferably 70% by mass or more, more preferably 75% by mass from the viewpoint of easily removing the alcohol contained in the polyimide-based resin composition (a) together with the deposited polyimide-based resin. % or more, more preferably 80 mass % or more, still more preferably 85 mass % or more, particularly preferably 90 mass % or more. The solvent to be brought into contact with the polyimide-based resin in the step (3) may be water or a mixture of water and another solvent (for example, another poor solvent), but the content of alcohol in the solvent containing water as a main component is , It is usually 20 mass % or less with respect to the whole solvent, Preferably it is 10 mass % or less, More preferably, it is 5 mass % or less, More preferably, it is 3 mass % or less.

In the step (3), when the mass of the polyimide-based resin composition (a) is W ₁ , and the mass of the solvent mainly composed of water to be brought into contact with the polyimide-based resin composition (a) is W ₂ , W the ratio of W ₂ to ₁ (W ₂ / W ₁₎ is a polyimide in an easy point of view the removal of the alcohol contained in the resin composition (a), preferably 4 or more, more preferably 5 or more, more preferably Preferably it is 6 or more, Especially preferably, it is 7 or more. Further, the ratio (W ₂ /W ₁ ) is preferably 50 or less, more preferably 40 or less, still more preferably 30 or less, particularly preferably 20 or less from the viewpoint of reducing the amount of waste liquid. The contact time is preferably 10 minutes or more, more preferably 15 minutes or more, still more preferably 20 minutes or more from the viewpoint of easily removing the alcohol contained in the polyimide-based resin composition (a). The contact time is preferably 120 minutes or less, more preferably 100 minutes or less, and still more preferably 80 minutes or less from the viewpoint of production efficiency.

In the step (3), the contact of the polyimide-based resin composition (a) with a solvent containing water as a main component may be performed by contacting the polyimide-based resin composition (a) with a solvent containing water as a main component once. , the solvent having water as a main component may be divided into a plurality of times and brought into contact, or the polyimide-based resin composition (a) may be continuously brought into contact with a solvent containing water as a main component. When the solvent containing water as a main component is continuously or divided into a plurality of times and contacted with the polyimide-based resin composition (a), the mass W ₂ of the solvent containing water as a main component is continuously or divided into multiple times and contacted, It is the total mass of the solvent which has water as a main component, and contact time is also total time. From the viewpoint of easily removing the alcohol contained in the polyimide-based resin composition (a) efficiently, it is preferable to contact the polyimide-based resin composition (a) with a solvent containing water as a main component in two or more times.

<Process (4)>

The manufacturing method of this invention solid-liquid-separate the mixture containing the polyimide-type resin obtained by making it contact with the solvent which has water as a main component in the process (3), The polyimide-type resin composition containing the polyimide-type resin which precipitated The step (4) of obtaining may be further included. The polyimide-type resin composition obtained in the process (4) is also called "polyimide-type resin composition (b)." The contact in the step (3) and the solid-liquid separation in the step (4) are a method generally called filtration, specifically, a method of separating by gravity through a filter having different permeability between the precipitate and the solvent; A method of separating by centrifugal force and a method of separating by a pressure difference are mentioned. A centrifugal filter, a Drew filter filter, a suction filter, a vacuum filter, etc. are mentioned as an example of a filter which can be used. Specifically, the steps (3) and (4) may be performed by solid-liquid separation by filtration while simultaneously adding a solvent containing water as a main component to the polyimide-based resin composition (a), or the polyimide-based resin composition ( After adding and mixing the solvent which has water as a main component to a), you may carry out solid-liquid separation of the mixture.

<Process (Y)>

Before the polyimide-based resin composition (a) and the solvent containing water as a main component are brought into contact in the step (3), the polyimide-based resin composition (a) obtained in the step (2) contains an alcohol having 1 to 4 carbon atoms. step (Y) of obtaining a polyimide-based resin composition containing a precipitated polyimide-based resin by contacting the solvent, preferably a solvent containing an alcohol having 1 to 4 carbon atoms as a main component, and separating the obtained mixture into solid-liquid. also be The polyimide-based resin composition obtained in the step (Y) is also referred to as a polyimide-based resin composition (a'). By performing the process (Y), the impurities etc. contained in the polyimide-type resin composition (a) can be removed, it is easy to raise transparency of the polyimide-type resin film finally obtained, and it is easy to reduce YI value. The contact time is preferably 10 minutes or more, more preferably 15 minutes or more, still more preferably 20 minutes or more. As the solvent containing an alcohol having 1 to 4 carbon atoms used in the step Y, the solvent described in the step (1) is similarly suitable. The contact method is also not specifically limited, The method described above regarding the contact of the solvent which has the polyimide-type resin composition (a) and water as a main component in the process (3) is similarly suitable.

In the step (Y), let the mass of the polyimide-based resin composition (a) be W ₃ , and the mass of the solvent containing an alcohol having 1 to 4 carbon atoms to be brought into contact with the polyimide-based resin composition (a) is W ₄ that when the ratio of W ₄ of the _{W 3 (W 4 / W 3} ) is, in an easy-to-remove impurities contained in the polyimide-based resin composition (a) perspective, preferably it is 1 or more, more preferably 2 or more, more preferably 3 or more, and particularly preferably 4 or more. Further, the ratio (W ₄ /W ₃ ) is preferably 100 or less, more preferably 80 or less, still more preferably 60 or less, particularly preferably 40 or less from the viewpoint of reducing wastewater treatment. The contact time is preferably 1 minute or longer, more preferably 2 minutes or longer, still more preferably 3 minutes or longer from the viewpoint of easy removal of impurities contained in the polyimide-based resin composition (a). The contact time is preferably 60 minutes or less, more preferably 50 minutes or less, still more preferably 40 minutes or less from the viewpoint of production efficiency.

In the step (Y), the contact of the polyimide-based resin composition (a) and the alcohol-based solvent may be performed by contacting the polyimide-based resin composition (a) with an alcohol-based solvent once, or a plurality of alcohol-based solvents It may be carried out by dividing the circuit into contact, or the polyimide-based resin composition (a) may be continuously brought into contact with an alcohol-based solvent. When the alcohol-based solvent is continuously or divided into plural times and contacted with the polyimide-based resin composition (a), the mass W ₄ of the alcohol-based solvent is the total mass of the alcohol-based solvent continuously or divided into plural times and contacted. , and the contact time is also the total time. From a viewpoint of being easy to remove the impurities contained in polyimide-type resin composition (a) efficiently, it is preferable to divide alcohol-type solvent into polyimide-type resin composition (a) in two or more times, and to make it contact.

<Drying process>

By drying the polyimide-type resin composition (b) obtained after a process (3), polyimide-type resin powder is obtained. The said polyimide-type resin composition (b) is a composition also called a wet cake, and is an intermediate body for obtaining polyimide-type resin powder. Although content of water in a polyimide-type resin composition (b) changes with a filtration method, Generally, with respect to the total mass of the said polyimide-type resin composition (b), Preferably it is 5 mass % or more, More preferably is 10% by mass or more, more preferably 20% by mass or more. The upper limit of the water content is preferably 70% by mass or less, more preferably 50% by mass or less, based on the total mass of the polyimide-based resin composition, from the viewpoint of easy production of the polyimide-based resin powder by drying.

Content of C1-C4 alcohol in polyimide-type resin composition (b) obtained after a process (3) is easy to manufacture polyimide-type resin powder efficiently, The fall of the heat resistance of the film obtained, and coloring From the viewpoint of easy to prevent The lower limit of content of a C1-C4 alcohol is not specifically limited, A smaller one is preferable.

Content of the good solvent in the polyimide-type resin composition (b) obtained after a process (3) is easy to manufacture polyimide-type resin powder efficiently, and it is easy to prevent the fall of the heat resistance of the film obtained, and coloring From a viewpoint, it is preferably 5 mass % or less, more preferably 3 mass % or less, more preferably 2 mass % or less, even more preferably 1 mass % or less, particularly preferably 0.5 mass % or less, especially more Preferably it is 0.3 mass % or less. The lower limit of content of a good solvent is not specifically limited, The less one is preferable.

In the manufacturing method of this invention, polyimide-type resin powder can be manufactured by drying the polyimide-type resin composition (b) obtained through the process (3) and removing a solvent. In the polyimide-based resin composition (b), since the alcohol content has already been reduced, the alcohol removal step under a temperature condition of less than 100° C. for preventing a decrease in the heat resistance of the film and/or coloring of the film is , which is already unnecessary. In the manufacturing method of the present invention, after the step (3) of bringing the polyimide-based resin composition into contact with a solvent containing water as a main component, the mixture obtained in the step (3) is subjected to solid-liquid separation to obtain a polyimide-based resin composition (b) The step (4) may be further included, and the drying step of drying the obtained polyimide-based resin composition (b) to obtain polyimide-based resin powder may be further included. Drying conditions are not particularly limited as long as the solvent in the polyimide-based resin composition (b) is removed, and for example, heating at a temperature of about 50 to 250° C. for about 1 to 48 hours under reduced pressure or atmospheric pressure conditions, etc. may be a condition of From the viewpoint of easily increasing the production efficiency, preferably at a temperature of 100°C or higher, more preferably 150°C or higher, it may be dried by heating at a temperature of preferably 0.5 to 10 hours, more preferably 1 to 5 hours.

<Polyimide resin powder>

The polyimide-based resin powder produced by the production method of the present invention is L*≥90, -10≤a in the color difference measurement based on the L*a*b* color system (based on JIS Z 8781-4:2013). It is preferable to satisfy *≤10, and -10≤b*≤10. L* in the color difference measurement is preferably 90 or more, more preferably 93 or more, and still more preferably 95 or more from the viewpoint of easily improving 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 color difference measurement shows a red index, and from the viewpoint of easily increasing the visibility of the finally obtained polymer material, preferably -10 or more and 10 or less, more preferably -7 or more and 7 or less, further preferably It is usually -5 or more and 5 or less. b* in the color difference measurement shows a blue index, and from the viewpoint of easily increasing the visibility of the finally obtained polymer material, preferably -10 or more and 10 or less, more preferably -5 or more and 10 or less, further preferably It is usually -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 described in an Example.

The particle size distribution of the polyimide-based resin powder produced by the production method of the present invention is D ₅₀ , preferably 20, from the viewpoint of dissolving the powder in a solvent when a polymer material is produced using the powder. -800 micrometers, More preferably, it is 50-500 micrometers, More preferably, it is 100-300 micrometers. A particle size distribution can be measured using a particle size analyzer, for example, can be measured by the method described in an Example. The scattering the viewpoint of the powder, D ₁₀ is, preferably 5~500㎛, more preferably 30~300㎛, more preferably 70~200㎛. Further, from the viewpoint of suppressing the generation of the mass, D ₉₀ is, preferably 50~1000㎛, more preferably 100~700㎛, more preferably 200~500㎛.

<Polyimide-based resin>

In the manufacturing method of this invention, the at least 1 sort(s) of resin chosen from the group which consists of a polyimide resin, a polyamide-imide resin, and a polyamic-acid resin may be sufficient as polyimide-type resin. One type of polyimide-type resin may be sufficient as polyimide-type resin, and 2 or more types of polyimide-type resin may be sufficient as it. The polyimide-based resin is preferably a polyamide-imide resin from the viewpoint of film forming properties. It is preferable that polyimide-type resin is an aromatic polyimide-type resin. When the polyimide-based resin is aromatic, preferably 50 mol% or more, more preferably 70 mol% or more, more preferably 100 mol% of the structural units constituting the polyimide-based resin is aromatic. It indicates that it is a constituent unit containing

In one preferred embodiment of the present invention, the polyimide-based resin is a polyimide-based resin having a structural unit represented by Formula (1), or a structural unit represented by Formula (1) and Formula (2) It is preferable that it is a polyamideimide-type resin which has the structural unit shown. Formulas (1) and (2) will be described below, but the description of the formula (1) relates to both the polyimide-based resin and the polyamideimide resin, and the description of the formula (2) is, It relates to a polyamideimide-based resin.

[Formula 1]

The structural unit represented by Formula (1) is a structural unit formed by reacting a tetracarboxylic acid compound with a diamine compound, and the structural unit represented by Formula (2) is a structural unit formed by reacting a dicarboxylic acid compound with a diamine compound. is a constituent unit. In one preferred aspect of the present invention in which the polyimide-based resin is an aromatic polyimide-based resin, the tetracarboxylic acid compound constituting the structural unit represented by the formula (1) and the structural unit represented by the formula (2) It is preferable that at least 1 of , a diamine compound and a dicarboxylic acid compound is an aromatic compound (an aromatic tetracarboxylic compound, an aromatic diamine compound, and/or an aromatic dicarboxylic acid compound).

In the formula (2), Z is a divalent organic group, preferably a hydrocarbon group having 1 to 8 carbon atoms, a hydrocarbon group having 1 to 8 carbon atoms substituted with fluorine, an alkoxy group having 1 to 6 carbon atoms, or a fluorine substituted hydrocarbon group. It is a divalent organic group having 4 to 40 carbon atoms which may be substituted with an alkoxy group having 1 to 6 carbon atoms, more preferably a hydrocarbon group having 1 to 8 carbon atoms, a hydrocarbon group having 1 to 8 carbon atoms substituted with fluorine, and 1 to 6 carbon atoms. is a divalent organic group having 4 to 40 carbon atoms and having a cyclic structure which may be substituted with an alkoxy group or a fluorine-substituted alkoxy group having 1 to 6 carbon atoms. As a cyclic structure, an alicyclic ring, an aromatic ring, and a heterocyclic structure are mentioned. As an organic group of Z, Formula (20), Formula (21), Formula (22), Formula (23), Formula (24), Formula (25), Formula (26), Formula (27), Formula ( 28) and a group in which two non-adjacent bonds of the groups represented by the formulas (29) are substituted with hydrogen atoms and a divalent chain hydrocarbon group having 6 or less carbon atoms are exemplified, and as the heterocyclic structure of Z, a thiophene ring skeleton is A group having a branch is exemplified. From a viewpoint of being easy to reduce the YI value which is an index|index of the yellowness of an optical film, group represented by Formula (20) - Formula (27), and group which has thiophene ring frame|skeleton are preferable. In one embodiment of the present invention, the polyamide-based resin and the polyamideimide-based resin may contain one type of organic group or two or more types of organic groups as Z.

As an organic group of Z, Formula (20'), Formula (21'), Formula (22'), Formula (23'), Formula (24'), Formula (25'), Formula (26'), Formula ( 27'), Equation (28') and Equation (29'):

[Formula 2]

[In Formulas (20') to (29'), W ¹ and * are as defined in Formulas (20) to (29)]

The divalent organic group represented by is more preferable. In addition, the cyclic hydrogen atom in Formulas (20) - Formula (29) and Formula (20') - Formula (29') is a C1-C8 hydrocarbon group, a fluorine-substituted C1-C8 hydrocarbon group , an alkoxy group having 1 to 6 carbon atoms or a fluorine-substituted alkoxy group having 1 to 6 carbon atoms may be substituted.

When the resin has a structural unit in which Z in the formula (b) is represented by any of the above formulas (20') to (29'), the resin has the following formula (d1) in addition to the structural unit ):

[Formula 3]

[In formula (d1), R ²⁴ independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and R ²⁵ is R ²⁴ or -C(=O)-*, * represents a bond]

It is preferable from a viewpoint that it is easy to improve the film-forming property of a varnish, and it is easy to acquire the uniformity of the optical film obtained to further have the structural unit derived from the carboxylic acid represented by.

Examples of the alkyl group having 1 to 6 carbon atoms, the alkoxy group having 1 to 6 carbon atoms, and the aryl group having 6 to 12 carbon atoms for R ²⁴ include those exemplified for ^{R 1 to R 8 in Formula (3) to be described later.} have. Specifically, as the structural unit (d1) ^{, a structural unit in which both R 24} and R ²⁵ are hydrogen atoms (a structural unit derived from a dicarboxylic acid compound), R ²⁴ is both a hydrogen atom, and R ²⁵ is -C (= The structural unit (structural unit derived from a tricarboxylic acid compound) etc. which represent O)-* are mentioned.

In one embodiment of the present invention, the polyamideimide-based resin may contain a plurality of types of Z, and the plurality of types of Z may be the same as or different from each other. In particular, from the viewpoint of easily increasing the surface hardness of the film obtained from the polyimide-based resin powder and the viewpoint of improving the optical properties, at least a part of Z is represented by the formula (3a):

[Formula 4]

[In formula (3a), R ^g and R ^h each independently represent a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, R ^g and R ^{The hydrogen atoms contained in h} may be each independently substituted with a halogen atom, A, m and * are the same as A, m and * in Formula (3), and t and u are each independently 0 to 4 is an integer]

It is preferably represented by Equation (3)

[Formula 5]

[In formula (3), R ¹ to ^{R 8} each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and R ¹ to R ^{The hydrogen atoms contained in 8} may be each independently substituted with a halogen atom,

A is, independently of each other, 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 )- represents, R ⁹ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms which may be substituted with a halogen atom,

m is an integer from 0 to 4,

* indicates a bonding hand]

It is more preferable to be represented by

In formulas (3) and (3a), 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 )-, from the viewpoint of bending resistance of the film comprising the polyimide-based resin, Preferably -O- or -S- is represented, More preferably, -O- is represented.

R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or 6 carbon atoms. to 12 aryl groups. R ^g and R ^h each independently represent a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy 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, 2-methyl-butyl group , 3-methylbutyl group, 2-ethyl-propyl group, n-hexyl group, and the like. Examples of the alkoxy group having 1 to 6 carbon atoms include a methoxy group, an ethoxy group, a propyloxy group, an isopropyloxy group, a butoxy group, an isobutoxy group, a tert-butoxy group, a pentyloxy group, a hexyloxy group, and a cyclohexyloxy group. time, and the like. Examples of the aryl group having 6 to 12 carbon atoms include a phenyl group, a tolyl group, a xylyl group, a naphthyl group, and a biphenyl group. From the viewpoint of the surface hardness and flexibility of the film containing the polyimide-based resin, R ¹ to ^{R 8} each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom. Here, ^{the hydrogen atoms contained in R 1} to ^{R 8} , R ^g and R ^h may each independently be substituted with a halogen atom.

R ⁹ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms which may be substituted with a halogen atom. Examples of the monovalent hydrocarbon group having 1 to 12 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 group. -Butyl group, 3-methylbutyl group, 2-ethyl-propyl group, n-hexyl group, n-heptyl group, n-octyl group, tert-octyl group, n-nonyl group, n-decyl group, etc. are mentioned. and these may be substituted with a halogen atom. As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned. Polyimide-type resin may contain multiple types of A, and multiple types of A may mutually be same or different.

t and u in formula (3a) are mutually independently an integer of 0-4, Preferably it is an integer of 0-2, More preferably, it is 0 or 1, More preferably, it is 0.

In Formulas (3) and (3a), m is an integer in the range of 0 to 4, and when m is in this range, the bending resistance and elastic modulus of the film containing the said polyimide-type resin will become favorable easily. Further, in formulas (3) and (3a), m is preferably an integer in the range of 0 to 3, more preferably 0 to 2, still more preferably 0 or 1, particularly preferably 0 . When m is in this range, it will be easy to improve the bending resistance and elastic modulus of the film containing the said polyimide-type resin. In addition, Z may contain 1 type, or 2 or more types of structural units represented by Formula (3) and Formula (3a), From a viewpoint of the improvement of the elasticity modulus of an optical film, and bending resistance, and YI value reduction, especially m Two or more types of structural units having different values of , preferably two types of structural units having different values of m may be included. In that case, from the viewpoint of easily expressing the high elastic modulus, bending resistance, and low YI value of the film containing the polyimide-based resin, the resin is Z in Z, m is 0, represented by formulas (3) and (3a), It is preferable to contain a structural unit, and it is more preferable to further contain, in addition to the structural unit, structural units represented by formulas (3) and (3a) wherein m is 1 . Moreover, in addition to the structural unit represented by Formula (2) which has Z represented by Formula (3) where m is 0, it is also preferable to have a structural unit further represented by said Formula (d1).

In one preferred embodiment of the present invention, the resin has, as a structural unit represented by formula (3), a structural unit in which m=0 and R ⁵ to ^{R 8} are hydrogen atoms. In a more preferred embodiment of the present invention, the resin is a structural unit represented by formula (3), wherein m=0 and R ⁵ to ^{R 8} are hydrogen atoms, and a structural unit represented by formula (3'):

[Formula 6]

It has a constituent unit represented by . In this case, it is easy to improve the surface hardness and bending resistance of the film containing the said polyimide-type resin, and it is easy to reduce YI value.

In one preferred embodiment of the present invention, when the total of the structural unit represented by the formula (1) and the structural unit represented by the formula (2) of the polyamideimide-based resin is 100 mol%, the formula (3) or The proportion of the structural unit represented by the formula (3a) is preferably 20 mol% or more, more preferably 30 mol% or more, still more preferably 40 mol% or more, still more preferably 50 mol% or more, particularly Preferably it is 60 mol% or more, Preferably it is 90 mol% or less, More preferably, it is 85 mol% or less, More preferably, it is 80 mol% or less. If the ratio of the structural unit represented by Formula (3) or Formula (3a) is more than the said lower limit, it will be easy to raise the surface hardness of the film containing the said polyimide-type resin, and also to raise bending resistance and elasticity modulus easily. When the ratio of the structural unit represented by Formula (3) or Formula (3a) is below the above upper limit, increase in the viscosity of the resin-containing varnish due to hydrogen bonding between amide bonds derived from Formula (3) or Formula (3a) is suppressed, , it is easy to improve the workability of the film.

In addition, when the polyamideimide-based resin has a structural unit of Formula (3) or Formula (3a) where m=1 to 4, the structural unit represented by Formula (1) and Formula (2) of the polyamideimide-based resin When the total of the structural units represented by is 100 mol%, the proportion of the structural units of formula (3) or formula (3a) wherein m is 1 to 4 is preferably 2 mol% or more, more preferably 4 mol% or more, more preferably 6 mol% or more, particularly preferably 8 mol% or more, preferably 70 mol% or less, more preferably 50 mol% or less, still more preferably 30 mol% or less, more More preferably, it is 15 mol% or less, Especially preferably, it is 12 mol% or less. It is easy to improve the surface hardness and bending resistance of the film containing the said polyimide-type resin as the ratio of the structural unit of Formula (3) whose m is 1-4 is more than said lower limit. When the ratio of the structural units of formula (3) or formula (3a) in which m is 1 to 4 is equal to or less than the above upper limit, the increase in the viscosity of the resin-containing varnish due to hydrogen bonds between amide bonds derived from formula (3) is suppressed, It is easy to improve the workability of a film. In addition, content of the structural unit represented by Formula (1), Formula (2), Formula (3), or Formula (3a) ^{can be measured using 1} H-NMR, for example, or from the introduction ratio of a raw material can also be calculated.

In one preferred embodiment of the present invention, preferably 30 mol% or more, more preferably 40 mol% or more, still more preferably 45 mol% or more, still more preferably, of Z in the polyamideimide-based resin. is 50 mol% or more, particularly preferably 70 mol% or more, is a structural unit represented by formula (3) or formula (3a) in which m is 0-4. When more than the said lower limit of Z is a structural unit represented by Formula (3) or Formula (3a) where m is 0-4, it is easy to raise the surface hardness of the film containing the said polyimide-type resin, and bending resistance And it is easy to raise an elasticity modulus as well. Moreover, 100 mol% or less of Z in polyamideimide-type resin should just be a structural unit represented by Formula (3) or Formula (3a) where m is 0-4. In addition, the ratio of the structural unit represented by Formula (3) or Formula (3a) in which m is 0-4 in resin ^{can be measured using 1} H-NMR, for example, or calculated from the introduction ratio of a raw material. You may.

In one preferred embodiment of the present invention, preferably 5 mol% or more, more preferably 8 mol% or more, still more preferably 10 mol% or more, particularly preferably, of Z in the polyamideimide-based resin 12 mol% or more is represented by Formula (3) or Formula (3a) whose m is 1-4. When the above lower limit of Z of the polyamideimide-based resin or more is expressed by formula (3) or formula (3a) wherein m is 1-4, it is easy to increase the surface hardness of the film containing the polyimide-based resin, and It is easy to increase bending resistance and elastic modulus. Further, preferably 90 mol% or less, more preferably 70 mol% or less, more preferably 50 mol% or less, particularly preferably 30 mol% or less of Z is the formula (3) in which m is 1-4 Or it is preferable to be represented by Formula (3a). When the above upper limit of Z is represented by formula (3) or formula (3a) wherein m is 1-4, m is 1-4 for hydrogen bond between amide bonds derived from formula (3) or formula (3a) By suppressing the increase in the viscosity of the resin containing varnish, it is easy to improve the workability of a film. In addition, the ratio of the structural unit represented by Formula (3) or Formula (3a) in which m is 1 to 4 in the resin ^{can be measured using, for example, 1} H-NMR, or can be calculated from the introduction ratio of the raw material. may be

In Formulas (1) and (2), X represents, independently of each other, a divalent organic group, preferably a divalent organic group having 4 to 40 carbon atoms, more preferably having 4 to 40 carbon atoms having a cyclic structure. represents a divalent organic group of As a cyclic structure, an alicyclic ring, an aromatic ring, and a heterocyclic structure are mentioned. In the organic group, a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group, and in that case, the hydrocarbon group and the fluorine-substituted hydrocarbon group preferably have 1 to 8 carbon atoms. In one Embodiment of this invention, polyimide-type resin or polyamide-imide-type resin may contain multiple types of X, and multiple types of X may mutually be same or different. X is represented by Formula (10), Formula (11), Formula (12), Formula (13), Formula (14), Formula (15), Formula (16), Formula (17), and Formula (18) energy; a group in which a hydrogen atom in the groups represented by such formulas (10) to (18) is substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; and a chain hydrocarbon group having 6 or less carbon atoms.

[Formula 7]

In formulas (10) to (18), * represents a bond,

V ¹ , V ² and V ³ are, independently of each other, a single bond, -O-, -S-, -CH ₂ -, -CH ₂ -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, -SO ₂ -, -CO- or -N(Q)-. Here, Q represents a monovalent hydrocarbon group having 1 to 12 carbon atoms which may be substituted with a halogen atom. Examples of the monovalent hydrocarbon group having 1 to 12 carbon atoms include the groups described above for ^{R 9 .}

In one example, V ¹ and V ³ are a single bond, -O- or -S-, and V ² is -CH ₂ -, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ - or -SO ₂ -. The ^{bonding position of V 1} and V ² to each ring, and the bonding position to each ring of V ² and V ³ are each independently of each other, preferably meta position or para position with respect to each ring, more preferably is the para position.

Among the groups represented by formulas (10) to (18), formulas (13), (14), and (15) from the viewpoint of easily improving the surface hardness and bending resistance of the film containing the polyimide-based resin. , The group represented by Formula (16) and Formula (17) is preferable, and the group represented by Formula (14), Formula (15), and Formula (16) is more preferable. In addition, V ¹ , V ² and V ³ are preferably a single bond, -O- or -S-, independently of each other, from the viewpoint of easily increasing the surface hardness and flexibility of the film containing the polyimide-based resin. , a single bond or -O- is more preferable.

In a preferred embodiment of the present invention, at least a part of a plurality of Xs in the formulas (1) and (2) is represented by the formula (4):

[Formula 8]

[In formula (4), R ¹⁰ to ^{R 17} each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, R ¹⁰ to ^{R 17} The hydrogen atoms contained in may be each independently substituted with a halogen atom, and * represents a bond.]

It is a unit represented by If at least one part of some X in Formula (1) and Formula (2) is group represented by Formula (4), it will be easy to raise the surface hardness and transparency of the film containing the said polyimide-type resin.

In formula (4), R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ and R ¹⁷ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. an alkoxy group or an aryl group having 6 to 12 carbon atoms. As a C1-C6 alkyl group, a C1-C6 alkoxy group, or a C6-C12 aryl group, a C1-C6 alkyl group in Formula (3), a C1-C6 alkoxy group, or a C6-C12 What was exemplified as the aryl group of R ¹⁰ to ^{R 17} each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, wherein R ¹⁰ to ^{R 17} The hydrogen atoms contained in may be each independently substituted by the halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R ¹⁰ to ^{R 17} each independently represent a hydrogen atom, a methyl group, a fluoro group, a chloro group or a trifluoromethyl group from the viewpoint of surface hardness, transparency, and bending resistance of the optical film, and further Preferably R ¹⁰ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ represent a hydrogen atom, R ¹¹ and R ¹⁷ represent a hydrogen atom, a methyl group, a fluoro group, a chloro group or a trifluoromethyl group, in particular Preferably, R ¹¹ and R ¹⁷ represent a methyl group or a trifluoromethyl group.

In a preferred embodiment of the present invention, the structural unit represented by the formula (4) is the formula (4'):

[Formula 9]

is a structural unit represented by , that is, at least a part of a plurality of X among the plurality of structural units represented by formulas (1) and (2) is a structural unit represented by formula (4'). In this case, while improving the solubility to the solvent of polyimide-type resin and improving the storage stability of the varnish containing the said resin by frame|skeleton containing the element fluorine, it is easy to reduce the viscosity of the said varnish, and an optical film It is easy to improve the machinability of Moreover, it is easy to improve the optical characteristic of an optical film by the frame|skeleton containing a fluorine element.

In one preferred embodiment of the present invention, of X in the polyimide-based resin, preferably 30 mol% or more, more preferably 50 mol% or more, still more preferably 70 mol% or more of the formula (4), In particular, it is represented by Formula (4'). When X within the above range in the polyimide-based resin is represented by Formula (4), particularly Formula (4'), the solubility of the resin in the solvent tends to improve due to the skeleton containing elemental fluorine, and the resin is contained While it is easy to improve the storage stability of the varnish to make, it is easy to reduce the viscosity of the said varnish, and it is easy to improve the workability of the film containing the said polyimide-type resin. Moreover, the optical characteristic of the film containing the said polyimide-type resin is also easy to improve with frame|skeleton containing a fluorine element. Moreover, Preferably, 100 mol% or less of X in the said polyimide-type resin is represented by Formula (4), especially Formula (4'). X in the polyamideimide-based resin may be a formula (4), particularly a formula (4'). The ratio of the structural unit represented by Formula (4) of X in the resin ^{can be measured, for example, using 1} H-NMR, or can be calculated from the introduction ratio of the raw material.

In Formula (1), Y represents a tetravalent organic group, Preferably a C4-C40 tetravalent organic group is represented, More preferably, the C4-C40 tetravalent organic group which has a cyclic structure is represented. As a cyclic structure, an alicyclic ring, an aromatic ring, and a heterocyclic structure are mentioned. The organic group is an organic group in which a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group, and in that case, the hydrocarbon group and the fluorine-substituted hydrocarbon group preferably have 1 to 8 carbon atoms. In one Embodiment of this invention, polyimide-type resin may contain multiple types of Y, and multiple types of Y may mutually be same or different. As Y, the following formulas (20), (21), (22), (23), (24), (25), (26), (27), (28) and a group represented by formula (29); a group in which a hydrogen atom in the groups represented by such formulas (20) to (29) is substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; and a tetravalent chain hydrocarbon group having 6 or less carbon atoms.

[Formula 10]

In formulas (20) to (29), * represents a bond,

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 an arylene group having 6 to 20 carbon atoms in which a hydrogen atom may be substituted with a fluorine atom, and specific examples thereof include a phenylene group.

Among the groups represented by formulas (20) to (29), from the viewpoint of surface hardness and bending resistance of the film containing the polyimide-based resin, it is represented by formula (26), formula (28) or formula (29), It is preferable to have a group represented by the formula (26), and more preferably a group represented by the formula (26). In addition, W ¹ _{is a single bond, -O-, -CH 2} -, -CH ₂ -CH ₂ -, independently of each other, from the viewpoint of easily increasing the surface hardness and bending resistance of the optical film and reducing the YI value. , -CH(CH ₃ )-, -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ - is preferably a single bond, -O-, -CH ₂ -, -CH(CH ₃ )- , -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ - is more preferable, and it is more preferably a single bond, -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ -.

In a preferred embodiment of the present invention, at least a part of the plurality of Y in the formula (1) is the formula (5):

[Formula 11]

[In formula (5), R ¹⁸ to ^{R 25} each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, R ¹⁸ to ^{R 25} The hydrogen atoms contained in may be each independently substituted with a halogen atom,

* indicates a bonding hand]

and/or equation (9)

[Formula 12]

[In formula (9), R ³⁵ to ^{R 40} 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, and the hydrogen atoms contained in ^{R 35} to ^{R 40 are mutually} Independently, it may be substituted with a halogen atom, and * represents a bond.]

It is a unit represented by When at least a part of some Y in Formula (1) is group represented by Formula (5) and/or Formula (9), the solubility to the solvent of polyimide-type resin is improved, and the varnish containing polyimide-type resin It is easy to reduce a viscosity and it is easy to improve the workability of the film containing the said polyimide-type resin. Moreover, it is easy to improve the optical characteristic of an optical film.

In formula (5), R ¹⁸ , R ¹⁹ , R ²⁰ , R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. an alkoxy group or an aryl group having 6 to 12 carbon atoms. As a C1-C6 alkyl group, a C1-C6 alkoxy group, and a C6-C12 aryl group, a C1-C6 alkyl group in Formula (3), a C1-C6 alkoxy group, or a C6-C12 Examples of the aryl group include those exemplified above. R ¹⁸ to ^{R 25} each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, where R ¹⁸ to ^{R 25} The contained hydrogen atoms may be each independently substituted with a halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R ¹⁸ to ^{R 25} are, independently of each other, more preferably a hydrogen atom, a methyl group, a fluoro group, a chloro group or a trifluoromethyl group from the viewpoint of easily improving the surface hardness, bending resistance and transparency of the optical film, Even more preferably, R ¹⁸ , R ^{19 ,} R ²⁰ , R ²³ , R ²⁴ and R ²⁵ are a hydrogen atom, R ²¹ and R ²² are a hydrogen atom, a methyl group, a fluoro group, a chloro group or a trifluoromethyl group, Particularly preferably, R ²¹ and R ²² are a methyl group or a trifluoromethyl group.

In formula (9), R ³⁵ to ^{R 40} are preferably represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom. Here, ^{the hydrogen atoms contained in R 35} to ^{R 40} may each independently be substituted with a halogen atom, and examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the alkyl group having 1 to 6 carbon atoms and the aryl group having 6 to 12 carbon atoms in R ³⁵ to ^{R 40 include those exemplified above, respectively.}

In one preferred embodiment of the present invention, the structural unit represented by the formula (5) is represented by the formula (5'), and the formula (9) is the formula (9'):

[Formula 13]

is represented by That is, at least a part of some Y is a structural unit represented by Formula (5') and/or Formula (9'). In this case, it is easy to reduce the viscosity of the said varnish while improving the solubility to the solvent of polyimide-type resin by frame|skeleton containing the element fluorine, and improving the storage stability of the varnish containing the said resin easily, It is easy to improve the workability of the film containing mid-type resin. Moreover, it is easy to improve the optical characteristic of the film containing the said polyimide-type resin by frame|skeleton containing a fluorine element.

In one preferred embodiment of the present invention, of Y in the polyimide-based resin, preferably 50 mol% or more, more preferably 60 mol% or more, still more preferably 70 mol% or more, formula (5), In particular, it is represented by Formula (5'). When Y within the above range in the polyimide-based resin is represented by the formula (5), particularly the formula (5'), the solubility of the polyimide-based resin in the solvent is increased by the skeleton containing the element fluorine, and the resin is It is easy to reduce the viscosity of the varnish to contain, and it is easy to improve the workability of the film containing the said polyimide-type resin. Moreover, it is easy to improve the optical characteristic of the film containing the said polyimide-type resin by frame|skeleton containing a fluorine element. Moreover, Preferably, 100 mol% or less of Y in the said polyimide-type resin is represented by Formula (5), especially Formula (5'). Y in polyimide-type resin may be Formula (5), Especially Formula (5') may be sufficient as it. The ratio of the structural unit represented by Formula (5) of Y in polyimide-type resin ^{can be measured using 1} H-NMR, for example, or can also be computed from the introduction ratio of a raw material.

The polyimide-based resin may be a resin containing a structural unit represented by the formula (30) and/or a structural unit represented by the formula (31), and other than the structural units represented by the formulas (1) and (2), Resin containing the structural unit represented by Formula (30) and/or the structural unit represented by Formula (31) may be sufficient.

[Formula 14]

In the formula (30), Y ¹ is a tetravalent organic group, preferably an organic group in which a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a 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), and Formula A group represented by (29), a group in which a hydrogen atom in the groups represented by the formulas (20) to (29) is substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group, and a tetravalent group having 6 or less carbon atoms A chain hydrocarbon group is exemplified. In one embodiment of the present invention, a polyimide-based resin may include a plurality of types of Y ^1, Y ¹ of a plurality of species, and may be same or different from each other.

In the formula (31), Y ² is a trivalent organic group, preferably an organic group in which a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group. Examples of Y ^2, of the formula 20, formula 21, formula 22, formula 23, formula 24, formula 25, formula 26, formula 27, formula 28 and a group in which any one of the bonds of the group represented by the formula (29) is substituted with a hydrogen atom, and a trivalent chain hydrocarbon group having 6 or less carbon atoms. In one embodiment of the present invention, a polyimide-based resin may include a plurality of types of Y ^2, Y ² is a plurality of types, and may be same or different from each other.

In Formulas (30) and (31), X ¹ and X ² are each independently a divalent organic group, and preferably a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group. it is a device As X ¹ and X ² , Formulas (10), (11), (12), (13), (14), (15), (16), (17) and Formulas above the group represented by (18); a group in which a hydrogen atom in the groups represented by such formulas (10) to (18) is substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; and a chain hydrocarbon group having 6 or less carbon atoms.

In one embodiment of the present invention, the polyimide-based resin is a structural unit represented by formulas (1) and/or (2), and optionally, formulas (30) and/or (31) made up of constituent units. In addition, from the viewpoint of optical properties, surface hardness, and bending resistance of the film containing the polyimide-based resin, in the polyimide-based resin, the structural units represented by formulas (1) and (2) are, Based on 1) and Formula (2), and optionally the total structural units represented by Formulas (30) and (31), preferably 80 mol% or more, more preferably 90 mol% or more, still more preferably preferably 95 mol% or more. In addition, in polyimide-type resin, the structural unit represented by Formula (1) and Formula (2) is Formula (1) and Formula (2), and Formula (30) and/or Formula (31) in some cases. It is usually 100% or less based on the total structural unit represented by . In addition, the said ratio ^{can be measured using 1} H-NMR, for example, or can also be computed from the introduction ratio of a raw material.

In one embodiment of the present invention, the content of the polyimide-based resin in the film containing the polyimide-based resin is preferably 10 parts by mass or more, more preferably 30 parts by mass or more with respect to 100 parts by mass of the film. It is mass part or more, More preferably, it is 50 mass parts or more, Preferably it is 99.5 mass parts or less, More preferably, it is 95 mass parts or less. When content of polyimide-type resin is in the said range, it will be easy to improve the optical characteristic and elastic modulus of a film.

The weight average molecular weight (Mw) of the polyimide-based resin is, in terms of standard polystyrene, preferably 230,000 or more, more preferably 250,000 from the viewpoint of easily increasing the surface hardness and bending resistance of the film containing the polyimide-based resin. or more, more preferably 270,000 or more, particularly preferably 300,000 or more. In addition, from the viewpoint of easily improving the solubility of the polyimide-based resin in the solvent and improving the stretchability and workability of the film, the weight average molecular weight of the resin is preferably 1,000,000 or less, more preferably 800,000 or less, more preferably 700,000 or less, particularly preferably 500,000 or less. A weight average molecular weight can perform a GPC measurement, for example, can be calculated|required by standard polystyrene conversion, for example, may be computed by the method as described in an Example.

In the polyamideimide-based resin, the content of the structural unit represented by the formula (2) is preferably 0.1 mol or more, more preferably 0.5 mol or more, with respect to 1 mol of the structural unit represented by the formula (1); More preferably, it is 1.0 mol or more, Especially preferably, it is 1.5 mol or more, Preferably it is 6.0 mol or less, More preferably, it is 5.0 mol or less, More preferably, it is 4.5 mol or less. It will be easy to raise the surface hardness of an optical film as content of the structural unit represented by Formula (2) is more than the said minimum. Moreover, when content of the structural unit represented by Formula (2) is below the said upper limit, the thickening by the hydrogen bond between amide bonds in Formula (2) is suppressed, and it is easy to improve the workability of an optical film.

In one preferred embodiment of the present invention, the polyimide-based resin may also contain a halogen atom such as a fluorine atom, which can be introduced by, for example, the fluorine-containing substituent described above. When polyimide-type resin contains a halogen atom, the elasticity modulus of the film containing the said polyimide-type resin is improved, and it is easy to reduce YI value. When the elastic modulus of a film is high and the said film is used in a flexible display device, it will be easy to suppress generation|occurrence|production of the said film, such as a wound and a wrinkle. Moreover, when YI value of a film is low, it will become easy to improve transparency and visibility of the said film. The halogen atom is preferably a fluorine atom. As a preferable fluorine-containing substituent in order to make polyimide-type resin contain a fluorine atom, a fluoro group and a trifluoromethyl group are mentioned, for example.

Content of the halogen atom in polyimide-type resin becomes like this on the basis of the mass of polyimide-type resin, Preferably it is 1-40 mass %, More preferably, it is 5-40 mass %, More preferably, it is 5-30 mass %. mass %. When content of a halogen atom is more than the said lower limit, the elasticity modulus of the film containing the said polyimide-type resin is improved more, water absorption is lowered, YI value is further reduced, and transparency and visibility are easy to improve more. If content of a halogen atom is below the said upper limit, it will become easy to synthesize|combine resin.

The imidation ratio of polyimide-type resin becomes like this. Preferably it is 90 % or more, More preferably, it is 93 % or more, More preferably, it is 96 % or more, and is usually 100 % or less. It is preferable that the imidation ratio is more than the said lower limit from a viewpoint of being easy to improve the optical homogeneity of the film containing the said polyimide-type resin. The imidation ratio represents the ratio of the molar amount of the imide bond in the polyimide-based resin to a value twice the molar amount of the structural unit derived from the tetracarboxylic acid compound in the polyimide-based resin. In addition, when the polyimide-based resin contains a tricarboxylic acid compound, a value twice the molar amount of the structural unit derived from the tetracarboxylic acid compound in the polyimide-based resin and the structural unit derived from the tricarboxylic acid compound The ratio of the molar amount of the imide bond in the polyimide-based resin and the polyamideimide-based resin to the sum of the molar amounts is shown. In addition, the imidation rate can be calculated|required by IR method, NMR method, etc., for example, in NMR method, it can measure by the method as described in the Example.

A commercial item may be used for polyimide-type resin. As a commercial item of polyimide resin, Mitsubishi Gas Chemical Co., Ltd. product Neoprime (trademark), Kawamura Industrial Co., Ltd. product KPI-MX300F etc. are mentioned, for example.

<Method for producing resin>

The polyimide-based resin can be produced using, for example, a tetracarboxylic acid compound and a diamine compound as main raw materials, and the polyamideimide-based resin is, for example, a tetracarboxylic acid compound, a dicarboxylic acid compound, and a diamine compound. It can be manufactured using as the main raw material. Here, it is preferable that a dicarboxylic acid compound contains the compound represented by Formula (3'') at least.

[Formula 15]

[In formula (3''), R ¹ to ^{R 8} each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and R ¹ The ^{hydrogen atoms included in 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 )- represents,

R ⁹ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms which may be substituted with a halogen atom,

m is an integer from 0 to 4,

R ³¹ and R ³² are, independently of each other, a hydroxyl group, a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group or a chlorine atom; indicate.]

In one preferred embodiment of the present invention, the dicarboxylic acid compound is a compound represented by formula (3'') in which m is 0. As the dicarboxylic acid compound, in addition to the compound represented by the formula (3'') in which m is 0, it is more preferable to use a compound represented by the formula (3'') in which A is an oxygen atom. Moreover, in another preferable embodiment, a dicarboxylic acid compound is a compound represented by Formula (3'') in which ^{R 31} and R ^{32 are chlorine atoms.} Moreover, you may use a diisocyanate compound instead of a diamine compound.

As a diamine compound used for manufacture of resin, an aliphatic diamine, an aromatic diamine, and these mixtures are mentioned, for example. In addition, in this embodiment, "aromatic diamine" represents the diamine in which the amino group is couple|bonded directly with the aromatic ring, and may contain the aliphatic group or another substituent in a part of the structure. This aromatic ring may be a monocyclic ring or a condensed ring may be sufficient as it, Although a benzene ring, a naphthalene ring, an anthracene ring, a fluorene ring, etc. are illustrated, It is not limited to these. Among these, a benzene ring is preferable. In addition, "aliphatic diamine" represents the diamine in which the amino group is directly couple|bonded with the aliphatic group, and may contain the aromatic ring and another 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 diamines, 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 diamine include p-phenylenediamine, m-phenylenediamine, 2,4-toluenediamine, m-xylylenediamine, p-xylylenediamine, 1,5-diaminonaphthalene, 2, Aromatic diamines having one aromatic ring, such as 6-diaminonaphthalene, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenylsulfone, 3,4'-diaminodiphenylsulfone, 3,3'-dia minodiphenylsulfone, 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, 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl (sometimes referred to 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- and aromatic diamines having two or more aromatic rings, such as chlorophenyl)fluorene and 9,9-bis(4-amino-3-fluorophenyl)fluorene. These can be used individually or in combination of 2 or more types.

Aromatic diamine is preferably 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylether, 3,3'-diaminodiphenylether , 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 (TFMB), 4,4'-bis (4-aminophenoxy) c) biphenyl, more preferably 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 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, 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl (TFMB), 4,4'-bis(4-aminophenoxy) ratio It is phenyl. These can be used individually or in combination of 2 or more types.

Among the above diamine compounds, it is preferable to use at least one selected from the group consisting of aromatic diamines having a biphenyl structure from the viewpoint of high surface hardness, high transparency, high flexibility, high bending resistance and low coloration of the optical film. 2,2'-dimethylbenzidine, 2,2'-bis(trifluoromethyl)benzidine, 4,4'-bis(4-aminophenoxy)biphenyl and 4,4'-diaminodiphenyl ether It is more preferable to use at least one selected from the group consisting of 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl (TFMB).

As a tetracarboxylic-acid compound used for manufacture of resin, Aromatic tetracarboxylic-acid compounds, such as aromatic tetracarboxylic dianhydride; and aliphatic tetracarboxylic acid compounds such as aliphatic tetracarboxylic dianhydride. A tetracarboxylic acid compound may be used independently and may be used in combination of 2 or more type. The tetracarboxylic acid compound may be a tetracarboxylic acid compound analog other than a dianhydride, such as an acid chloride compound.

Specific examples of the aromatic tetracarboxylic dianhydride include non-condensed polycyclic aromatic tetracarboxylic dianhydride, monocyclic aromatic tetracarboxylic dianhydride, and condensed polycyclic aromatic tetracarboxylic dianhydride. Examples of the non-condensed polycyclic aromatic tetracarboxylic dianhydride include 4,4'-oxydiphthalic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,2', 3,3'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 3 ,3',4,4'-diphenylsulfonetetracarboxylic 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 dianhydride (sometimes described as 6FDA) , 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 dianhydride and 4,4'-(m-phenylenedioxy)diphthalic dianhydride. Examples of the monocyclic aromatic tetracarboxylic dianhydride include 1,2,4,5-benzenetetracarboxylic dianhydride, and examples of the condensed polycyclic aromatic tetracarboxylic dianhydride include, 2,3,6,7-naphthalenetetracarboxylic dianhydride is mentioned.

Among these, preferably 4,4'-oxydiphthalic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, and 2,2',3,3'-benzophenonetetracarboxylic acid dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-di Phenylsulfonetetracarboxylic 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 dianhydride (6FDA), 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-di) Carboxyphenyl)ethane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, 4,4'-(p-phenylenedioxy)diphthalic dianhydride water and 4,4'-(m-phenylenedioxy)diphthalic dianhydride, more preferably 4,4'-oxydiphthalic dianhydride, 3,3',4,4'-biphenyl Tetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA), bis(3,4) -dicarboxyphenyl)methane dianhydride and 4,4'-(p-phenylenedioxy)diphthalic acid dianhydride are mentioned. These can be used individually or in combination of 2 or more types.

Examples of the aliphatic tetracarboxylic dianhydride include cyclic or acyclic aliphatic tetracarboxylic dianhydride. Cyclic aliphatic tetracarboxylic dianhydride is tetracarboxylic dianhydride having an alicyclic hydrocarbon structure, and specific examples thereof include 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4- Cycloalkanetetracarboxylic dianhydride such as cyclobutanetetracarboxylic dianhydride and 1,2,3,4-cyclopentanetetracarboxylic dianhydride, bicyclo[2.2.2]oct-7-ene-2,3; and 5,6-tetracarboxylic dianhydride, dicyclohexyl-3,3',4,4'-tetracarboxylic dianhydride, and positional isomers 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 types. 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, from the viewpoint of high surface hardness, high transparency, high flexibility, high bending resistance, and low coloring of the optical film, 4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 3,3 ',4,4'-diphenylsulfonetetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride Water, and mixtures thereof, are preferred, 3,3',4,4'-biphenyltetracarboxylic dianhydride and 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride, and mixtures thereof More preferably, 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA) is more preferable.

As a dicarboxylic acid compound used for manufacture of resin, Preferably terephthalic acid, 4,4'- oxybisbenzoic acid, or those acid chloride compounds are used. In addition to terephthalic acid, 4,4'-oxybisbenzoic acid, or their acid chloride compounds, other dicarboxylic acid compounds may be used. As another dicarboxylic acid compound, an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid, the acid chloride compound of those, an acid anhydride, etc. are mentioned, You may use in combination of 2 or more type. Specific examples include isophthalic acid; naphthalenedicarboxylic acid; 4,4'-biphenyldicarboxylic acid; 3,3'-biphenyldicarboxylic acid; A dicarboxylic acid compound of a chain hydrocarbon having 8 or less carbon atoms and two benzoic acids are linked by a single bond, -CH ₂ -, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, -SO ₂ -, or a phenylene group compounds and their acid chloride compounds. As a specific example, 4,4'-oxybis(benzoyl chloride) and terephthaloyl chloride are preferable, and it is more preferable to use 4,4'-oxybis (benzoyl chloride) and terephthaloyl chloride in combination.

In addition, in addition to the said tetracarboxylic acid compound, the said polyimide-type resin may further react with tetracarboxylic acid and tricarboxylic acid, and their anhydrides and derivatives, within the range which does not impair the various physical properties of an optical laminated body. .

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

As a tricarboxylic acid compound, an aromatic tricarboxylic acid, an aliphatic tricarboxylic acid, the acid chloride compound of those, an acid anhydride, etc. are mentioned, You may use in combination of 2 or more type. Specific examples include anhydride of 1,2,4-benzenetricarboxylic acid; 2,3,6-naphthalenetricarboxylic acid-2,3-anhydride; and compounds in which 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.

Production of resin WHEREIN: The usage-amount of a diamine compound, a tetracarboxylic-acid compound, and/or a dicarboxylic acid compound can be suitably selected according to the ratio of each structural unit of a desired polyimide-type resin.

In manufacture of resin, although the reaction temperature of a diamine compound, a tetracarboxylic acid compound, and a dicarboxylic acid compound is not specifically limited, For example, 5-350 degreeC, Preferably it is 20-200 degreeC, More preferably, 25- It is 100°C. Although reaction time is not specifically limited, either, For example, it is about 30 minutes - about 10 hours. If necessary, the reaction may be performed under an inert atmosphere or under reduced pressure. In a preferred embodiment, the reaction is carried out under normal pressure and/or in an inert gas atmosphere while stirring. In addition, it is preferable to perform reaction in the solvent inactive to reaction. The solvent is not particularly limited as long as it does not affect the reaction, and for example, water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, 1-methoxy- alcohol solvents such as 2-propanol, 2-butoxyethanol, and propylene glycol monomethyl ether; ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, γ-valerolactone, propylene glycol methyl ether acetate, and ethyl lactate; ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; alicyclic hydrocarbon solvents such as ethylcyclohexane; aromatic hydrocarbon solvents such as toluene and xylene; nitrile solvents such as acetonitrile; ether solvents such as tetrahydrofuran and dimethoxyethane; chlorine-containing solvents such as chloroform and chlorobenzene; amide solvents such as N,N-dimethylacetamide and N,N-dimethylformamide; 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, an amide type solvent can be used suitably from a solubility viewpoint.

In the imidation process in manufacture of polyimide-type resin, imidation can be carried out in presence of an imidation catalyst. Examples of the imidization catalyst include aliphatic amines such as tripropylamine, dibutylpropylamine, and ethyldibutylamine; 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 (2-picoline), 3-methylpyridine (3-picoline), 4-methylpyridine (4-picoline), 2-ethylpyridine, 3-ethylpyridine, 4-ethylpyridine and aromatic amines such as , 2,4-dimethylpyridine, 2,4,6-trimethylpyridine, 3,4-cyclopentenopyridine, 5,6,7,8-tetrahydroisoquinoline, and isoquinoline. . Moreover, it is preferable to use an acid anhydride with an imidation catalyst from a viewpoint of being easy to accelerate|stimulate imidation reaction. Examples of the acid anhydride include a conventional acid anhydride used in the imidation reaction, and specific examples thereof include aliphatic acid anhydrides such as acetic anhydride, propionic acid anhydride and butyric acid anhydride, and aromatic acid anhydrides such as phthalic acid.

The polyimide-based resin may be isolated (separated and purified) by a conventional method, for example, separation means such as filtration, concentration, extraction, crystallization, recrystallization, column chromatography, or a separation means combining these, a preferred embodiment , can be isolated by adding a large amount of alcohol such as methanol to a reaction solution containing a transparent polyamideimide-based resin to precipitate the resin, and performing concentration, filtration, drying, and the like.

The polyimide-type resin powder manufactured by the manufacturing method of this invention can be used as an optical member, for example. 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. A single layer may be sufficient as an optical member, and multiple layers may be sufficient as it. When an optical member is a multilayer, the same composition may be sufficient as each layer, and a different composition may be sufficient as it.

When using the polyimide-type resin powder manufactured by the manufacturing method of this invention as an optical member, the content rate of the polyimide-type resin in an optical member with respect to the total mass of an optical member, Preferably it is 40 mass % or more. More preferably, it is 50 mass % or more, More preferably, it is 70 mass % or more, More preferably, it is 80 mass % or more, Especially preferably, it is 90 mass % or more, Usually, it is 100 mass % or less. The bending resistance of an optical member is favorable as content rate of a polyimide-type resin is more than the said minimum.

(Inorganic material)

The optical member may further contain an inorganic material such as inorganic particles other than the polyimide-based 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 stability of the varnish containing the polyimide-based resin for producing an optical member, the inorganic material is preferably an inorganic particle, particularly a silica particle. Inorganic particles may be bonded to each other by a molecule having a siloxane bond.

The average primary particle diameter of the inorganic particles is usually 1 to 100 nm, preferably 5 to 80 nm, more preferably 7 to 50 nm, from the viewpoint of transparency of the optical member, mechanical properties, and suppression of aggregation of inorganic particles; 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 positive direction 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. % or more and 40 mass% or less. When the content of the inorganic material is within the above range, it tends to be easy to achieve both transparency and mechanical properties of the optical member.

(Ultraviolet absorber)

The optical member may contain the 1 type(s) 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|area of a resin material. The ultraviolet absorber may contain the compound which absorbs the light of the wavelength of 400 nm or less. Examples of the ultraviolet absorber include at least one compound selected from the group consisting of a benzophenone-based compound, a salicylate-based compound, a benzotriazole-based compound, and a triazine-based compound. Since deterioration of polyimide-type resin is suppressed when an optical member contains a ultraviolet absorber, 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 attached. For example, a "benzophenone-based compound" refers to a compound having benzophenone as a parent skeleton and a substituent bonded to benzophenone.

When the optical member contains the ultraviolet absorber, the content of the ultraviolet absorber is preferably 1 mass% or more, more preferably 2 mass% or more, still more preferably 3 mass% or more, with respect to 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 the suitable content varies depending on the ultraviolet absorber used, if the content of the ultraviolet absorber is adjusted so that the light transmittance at 400 nm is about 20 to 60%, the light resistance of the optical member can be improved and an optical member with high transparency can be obtained. can

(Other additives)

The optical member may contain another additive further. As another component, antioxidant, a mold release agent, a stabilizer, a bluing agent, a flame retardant, a pH adjuster, a silica dispersing agent, a lubricant, a thickener, a leveling agent, etc. are mentioned, for example.

To [ the content rate of another additive / mass of an optical member ], Preferably they are 0 mass % or more and 20 mass % or less, More preferably, they are 0 mass % or more and 10 mass % or less.

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

In the optical member, the total light transmittance (Tt) according to JIS K 7105:1981 is preferably 70% or more, more preferably 80% or more, still more preferably 85% or more, particularly preferably 90% or more, , usually 100% or less. When the optical member is attached to an image display apparatus as the total light transmittance (Tt) of an optical member is more than said lower limit, it will be easy to ensure sufficient visibility. The haze in the optical member is measured with a direct-reading haze computer (model HGM-2DP) manufactured by Suga Test Instruments Co., Ltd., and is preferably 1.0% or less, more preferably 0.8% or less, still more preferably 0.5% or less. , particularly preferably 0.3% or less, and usually 0% or more. When the haze of an optical member is below the said upper limit and attaches an optical member to flexible electronic devices, such as an image display apparatus, it will be easy to ensure sufficient visibility. The polyimide-based resin dissolved in the polyimide-based resin solution (a) used in the production method of the present invention, and/or the polyimide-based resin powder obtained by the production method of the present invention, has the above total light transmittance (Tt). ) and/or haze. The total light transmittance (Tt) and/or haze of the polyimide-based resin and the polyimide-based resin powder is measured in the shape of a molded article, for example, a film. The detail of the preparation method of a measurement sample and a measurement method is as described in an Example.

(Manufacturing method of optical member)

The above optical member, for example, an optical film can be manufactured using the polyimide-type resin powder manufactured by the manufacturing method of this invention. The manufacturing method is not specifically limited. For example, the following process:

(a) a step of forming a coating film by dissolving polyimide-based resin powder in a solvent and applying a liquid containing a polyimide-based resin (polyimide-based resin varnish) to a substrate (application step), and

(b) drying the applied liquid (varnish of polyimide-based resin) to form an optical member, particularly an optical film (polyimide-based resin film) (forming step)

An optical member can be manufactured by a manufacturing method comprising. Steps (a) and (b) can usually be performed in this order.

In the application step, polyimide-based resin powder is dissolved in a solvent, and if necessary, the ultraviolet absorber and other additives are added and stirred to prepare a polyimide-based resin-containing liquid (polyimide-based resin varnish). do.

The solvent used for preparation of a varnish will not be specifically limited if polyimide-type resin can be melt|dissolved. Examples of such solvents include amide 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, an amide solvent or a lactone solvent is preferable. Further, the varnish may contain water, an alcohol-based solvent, a ketone-based solvent, an acyclic ester-based solvent, an ether-based solvent, and the like.

Next, for example, using a varnish of a polyimide-based resin on a substrate such as a resin substrate, SUS belt, or glass substrate by a known roll-to-roll or arrangement method, cast molding, etc. A coating film can be formed by

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

You may perform the surface treatment process of surface-treating to the at least one surface of an optical member. Examples of the surface treatment include UV ozone treatment, plasma treatment, and corona discharge treatment.

Examples of the resin substrate include a PET film, a PEN film, a polyimide film, and a polyamideimide film. Among them, PET film, PEN film, polyimide film and other polyamideimide films are preferable from the viewpoint of excellent heat resistance. Moreover, a PET film is more preferable from a viewpoint of adhesiveness with an optical member, and cost.

An optical member can be manufactured using the polyimide-type resin powder obtained by the manufacturing method of this invention. Such an optical member has a 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, even more preferably 6.0 GPa or more, particularly preferably Preferably it is 10.0 GPa or more, More preferably, it is 8.0 GPa or more. When a flexible display bends as the elastic modulus of an optical member is below the said upper limit, damage to the other member by the said optical member can be suppressed. For the elastic modulus, for example, using Autograph AG-IS manufactured by Shimadzu Corporation, a stress-strain curve is measured for a 10 mm wide test piece under the conditions of a distance between chucks of 50 mm and a tensile rate of 20 mm/min. It can be measured from the slope. 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 has the above elastic modulus. desirable. The elastic modulus of a polyimide-type resin and polyimide-type resin powder is measured by the shape of a molded object (for example, a film). The detail of the preparation method of a measurement sample and a measurement method is as described in an Example.

The said optical member, especially an optical film, has the outstanding bending resistance. In a suitable embodiment of the present invention, the optical member has a number of reciprocating bendings until fracture, preferably 10,000 times or more, more preferably when R=1 mm, 135° weighted 0.75 kgf, and measured at a speed of 175 cpm 20,000 or more, more preferably 30,000 or more, even more preferably 40,000 or more, particularly preferably 50,000 or more.

The wrinkle which may arise when the optical member is bent as the number of reciprocating bending times of an optical member is more than the said lower limit can further be suppressed. Moreover, although the number of reciprocating bending times of an optical member is not restrict|limited, Usually, if bending 1,000,000 times is possible, it is practical enough. The number of reciprocal bending can be calculated|required using the test piece (optical member) of thickness 50 micrometers and width 10mm with the MIT bending fatigue tester (model 0530) manufactured by Toyo Seiki Seisakusho Co., Ltd., for example. The polyimide-based resin dissolved in the polyimide-based resin solution (a) used in the production method of the present invention, and/or the polyimide-based resin powder obtained by the production method of the present invention, has the above bending resistance. it is preferable The bending resistance of a polyimide-type resin and polyimide-type resin powder is measured by the shape of a molded object (for example, a film).

The said optical member can express the outstanding transparency. Therefore, the said optical member is very useful as an image display apparatus, especially as a front plate (window film) of a flexible display. In a preferred embodiment of the present invention, the optical member has a YI value based on JIS K7373:2006, preferably 5 or less, more preferably 3 or less, still more preferably 2.5 or less, particularly preferably 2.0 or less, preferably 0 or more. The optical member whose YI value is below the said upper limit can contribute to high visibility, such as a display apparatus. The polyimide-based resin dissolved in the polyimide-based resin solution (a) used in the production method of the present invention and/or the polyimide-based resin powder obtained by the production method of the present invention have the above YI value it is preferable The YI value of polyimide-type resin and polyimide-type resin powder is measured by the shape of a molded object, for example, a film. The detail of the preparation method of a measurement sample and a measurement method is as described in an Example.

Said optical member may be equipped with functional layers, such as an ultraviolet-ray absorption layer, an adhesion layer, a hue adjustment layer, and a refractive index adjustment layer, and a hard-coat layer.

The optical member manufactured using the polyimide-type resin powder of this invention, for example, an optical film is useful as a front plate of an image display apparatus, especially the window film which is a front plate of a flexible display. The said optical member can be arrange|positioned as a front plate on the visual recognition side surface of an image display apparatus, especially a flexible display. This front plate has a function of protecting the image display element in a flexible display. Since the image display device provided with the said optical member has high flexibility and bending resistance, and also has high surface hardness, when it bends, it does not damage another member, and also it is hard to generate|occur|produce a wrinkle in the optical member itself. , it is possible to advantageously suppress the wound on the surface.

As an image display apparatus, wearable devices, such as a television, a smart phone, a mobile phone, a car navigation system, a tablet PC, a portable game machine, electronic paper, an indicator, a bulletin board, a watch, 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 phone, car navigation, a tablet PC, a portable game machine, electronic paper, an indicator, a bulletin board, a watch, a wearable device, etc. are mentioned.

(Example)

Hereinafter, although an Example demonstrates this invention in more detail, this invention is not limited to the following Example. In the examples, "%" and "parts" mean mass % and mass parts unless otherwise specified.

(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 weighed out, and 10 mL of DMF (10 mmol lithium bromide) was added to dissolve completely. This solution was filtered with a chromatography disk (pore diameter 0.45 micrometers), and it was set as the sample solution.

(2) Measurement conditions

Device: HLC-8020GPC

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

Eluent (溶離液): DMF (10 mmol of lithium bromide added)

Flow rate: 1.0mL/min

Detector: RI Detector

Column temperature: 40℃

Injection volume: 100μL

Molecular weight standard: standard polystyrene

(Measurement of imidization rate)

The imidation rate was calculated|required as follows by <^{1>H-NMR measurement.}

(1) Pretreatment method

Polyimide resin A or polyamideimide resin A was dissolved in deuterated dimethyl sulfoxide (DMSO-d ₆ ) to obtain a 2% by mass solution as a measurement sample.

(2) Measurement conditions

Measuring device: JNM-ECZ400S/L1 400MHz NMR device made by Nippon Electronics Co., Ltd.

Standard: DMSO-d ₆ (2.5 ppm)

Sample temperature: room temperature

Integration count: 256 times

Relief time: 5 seconds

(3) Analysis method

(3-1) Imidization ratio of polyimide resin A

¹ H-NMR spectrum obtained from the measurement sample containing polyimide resin A WHEREIN: Among the observed benzene protons, the integral value of the benzene proton A derived from the structure which does not change before and after imidation was made into IntA.

In addition, the integral value of the amide proton derived from the amic-acid structure remaining in the observed polyimide resin was made into IntB. From this integral value, the imidation ratio of polyimide resin A was calculated|required based on the following formula|equation. In the following formula, α is the ratio of the number of benzene protons A to one amide proton in the case of polyamic acid (imidization rate 0%).

Imidization rate (%) = 100 × (1-α × IntB/IntA)

(3-2) Imidization rate of polyamideimide resin A

^{In the 1} H-NMR spectrum obtained from the measurement sample containing the polyamideimide resin A, the observed benzene proton is derived from a structure that does not change before and after imidization, and is derived from the amic acid structure remaining in the polyamideimide resin. The integral value of benzene proton C, which is not affected by the structure, was designated as IntC. In addition, the integral value of benzene proton D derived from the structure that does not change before and after imidation among the observed benzene protons and affected by the structure derived from the amic acid structure remaining in the polyamideimide resin was designated as IntD. From the obtained IntC and IntD, the beta value was calculated|required by the following formula|equation.

β=IntD/IntC

Next, in order to obtain a correlation formula for converting β into imidization ratio, β values are calculated in the same manner as above for a plurality of polyamideimide resins having different imidization ratios, and imidation ratios are used using HSQC spectrum. , and from these results, the following correlation was obtained.

Imidization rate (%) = k × β + 100

In the above correlation, k is a constant.

Next, β obtained for the polyamideimide resin A was substituted into the above correlation formula to obtain the imidation ratio (%) of the polyamideimide resin A.

(Measurement of chromaticity)

Using the polyimide resin powder placed in a petri dish as a measurement sample, using a colorimeter "CR-5" manufactured by Konica Minolta Co., Ltd., the chromaticity (according to JIS Z 8781-4:2013) under the following measurement conditions ) was measured.

<Measurement conditions>

Observation conditions: 2° field of view (CIE1931)

Observation light source: C

Color space: 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)

_{The polyimide-based resin powder was used as a measurement sample, and the particle size distribution (D 10} , D ₅₀ and D ₉₀ ) was measured under the following measurement conditions using a Microtrack particle size analyzer MT-3100II (manufactured by Nikiso Co., Ltd.). .

<Measurement conditions>

Particle refractive index: 1.53

Measurement method: dry laser diffraction method

(Gas Chromatograph: Determination of DMAc, Methanol Concentration)

The measurement was performed using gas chromatography (GC).

(1) Sample adjustment method

4 g of isopropanol was added to 1 g of resin, ultrasonication was performed for 30 minutes, and what filtered this with the chromatography disk (pore diameter 0.45 micrometer) was used as the measurement sample.

(2) DMAc measurement conditions

Device: Agilent 6890

Column: DB-WAX (250㎛ × 30m, 0.25㎛)

Inlet temperature: 150℃

Detector temperature: 250℃

Carrier gas: He

Flow rate: 1.0 mL/min (constant flow)

Injection volume: 1.0μL

Detection: FID

Quantitation: Absolute calibration curve method

Oven temperature program: 0-5 minutes: 50°C, 5-25 minutes: 50°C→250°C, 25-35 minutes: 250°C

(3) Measuring conditions for methanol

Device: Agilent 6890

Column: DB-5 (250㎛ × 30m, 0.25㎛)

Inlet temperature: 150℃

Detector temperature: 250℃

Carrier gas: He

Flow rate: 1.0 mL min (constant flow)

Injection volume: 1.0μL

Detection: FID

Quantitation: Absolute calibration curve method

Oven temperature program: 0-5 minutes: 50℃, 5-32 minutes: 50℃→320℃, 32-40 minutes: 320℃

(Karl Fischer: Measurement of moisture content)

Measurement was performed using the Karl Fischer method.

Apparatus: CA-200 manufactured by Mitsubishi Chemical Analytech Co., Ltd.

Measurement method: vaporization type coulometric method

Heating conditions: 200℃, 30 minutes

Sample amount: about 150mg

Anolyte: Aqua Micron AX

Catholyte: Aquamicron CXU

(TG-DTA: residual amount of solvent in dry powder)

The residual amount of the solvent remaining in the dry powder was measured using a differential thermal and thermogravimetric simultaneous measurement apparatus (TG/DTA6200 manufactured by SII Nanotechnology Co., Ltd.). Specifically, 25 mg of polyimide-based resin powder was put in an aluminum pan, and the temperature was raised at a rate of 10°C/min in a nitrogen atmosphere, and the mass (M1) of the polyimide-based resin powder at 200°C and 300°C The mass (M2) of the polyimide resin powder in was measured, the mass decrease rate in 200-300 degreeC was calculated|required from the following formula, and this was made into the solvent residual amount.

Mass reduction rate (%) at 200 to 300°C = (M1-M2)/M1×100

[Confirmation of solubility of resin in solvent]

Regarding the resin powder described in Synthesis Example 1 below, solubility in a solvent was confirmed by the following method.

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

As a result, it 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.

[Synthesis Example 1: Synthesis of polyimide-based resin]

Nitrogen was conducted to a reaction vessel equipped with a sufficiently dried stirrer and a thermometer, and the inside of the vessel was substituted with nitrogen. The inside of the reaction vessel is cooled to 10°C, 1567.4 parts of dimethylacetamide (DMAc) is placed in the vessel, and 91.8 parts of 2,2'-bis(trifluoromethyl)benzidine (TFMB) and 4,4'-(hexafluoro 38.6 parts of isopropylidene) diphthalic dianhydride (6FDA) was added, and it stirred for 3 hours.

Next, 4.3 parts of 4,4'-oxybis (benzoyl chloride) (OBBC) and 15.9 parts of terephthaloyl chloride (TPC) were added, stirred for 30 minutes, OBBC and TPC of the same amount were added, and it stirred at the same time. 1567.4 parts of DMAc and 3.5 parts of TPC were added to the produced|generated reaction liquid, and also it stirred at 10 degreeC for 2 hours.

Then, 26.2 parts of diisopropylethylamine and 62.1 parts of acetic anhydride are added, and after stirring for 30 minutes while maintaining at 10°C, 18.9 parts of 4-picoline is added, the reaction vessel is heated to 75°C, and further It stirred for 3 hours, and obtained the reaction liquid (1) containing polyimide-type resin.

When the reaction liquid (1) was cooled and lowered to 40°C or lower, 940.4 parts of methanol was added to obtain a reaction liquid (2).

Nitrogen was conducted to a reaction vessel equipped with a stirrer and a thermometer, and the inside of the vessel was substituted with nitrogen. 1452.2 parts of the reaction solution (2) was put into the reaction vessel while stirring at 20°C. Next, 1253.9 parts of methanol was dripped at a rate of 30 parts/min, and then 783.7 parts of ion-exchanged water was dripped at a rate of 7 parts/min, and white solid was precipitated. The white solid which precipitated was collected by centrifugal filtration, and the wet cake containing polyamideimide resin was obtained by washing|cleaning with methanol. 52 parts of polyamideimide resin powder were obtained by drying the obtained wet cake at 78 degreeC under reduced pressure. The weight average molecular weight of the obtained polyamideimide resin was 343,000, and the imidation rate was 97.0 %.

[Preparation of resin solution]

25 parts of the resin powder obtained by the synthesis example 1 was melt|dissolved in 475 parts of DMAc, and the polyimide-type resin solution in which the polyimide-type resin melt|dissolved in the good solvent was produced. In the following examples, the polyimide-based resin solution obtained by dissolving the resin powder obtained in Synthesis Example 1 in a good solvent is used, but the reaction solution (1) of Synthesis Example 1 is used as it is as a polyimide-based resin solution. You may use it, and the same result is obtained also in that case.

[Example 1: Crystallization and cleaning process]

200 parts of the produced polyimide-type resin solution was weighed and put into a glass beaker. When 301 parts of methanol was dripped while stirring with the stainless steel stirring blade, the liquid became cloudy in the middle of dripping. Then, when 150 parts of water was dripped, the degree of cloudiness became more deep. By suction filtration, particles were collected using a glass filter.

Next, put a silicone stopper at the outlet of the glass filter to prevent the solvent placed in the filter from leaking out, add 150 parts of methanol, hold for 30 minutes in a state where the particles are completely immersed, and then remove the silicone stopper , to separate solid and liquid. This operation was repeated twice. The second time, suction filtration was performed until the liquid stopped coming out.

Next, a silicone stopper was similarly applied, 150 parts of water was added, and after holding for 30 minutes in the state in which the particle|grains were fully immersed, the silicone stopper was removed and solid-liquid was isolate|separated. This operation was repeated 3 times. 3rd time, suction filtration was performed until the liquid stopped coming out. In this way, the resin composition containing resin and a solvent was obtained.

About the obtained resin composition, the amount of organic solvent was measured by the gas chromatography method, and the water content was measured by the Karl Fischer method.

[Drying process]

The obtained resin composition was weighed and taken into an aluminum cup, and it dried at 200 degreeC for 3 hours using the blow dryer (DKN302 manufactured by Yamato Scientific Co., Ltd.), and white powder was obtained.

About the obtained powder, the solvent residual amount was measured by the TG-DTA method, the chromaticity was measured with the colorimeter, and the particle size was measured with the particle size analyzer.

[Reference Comparative Example 1: Crystallization and Washing Process]

200 parts of the produced polyimide-type resin solution was weighed and put into a glass beaker. When 301 parts of methanol and 150.7 parts of water were dripped while stirring with the stainless steel stirring blade, particle|grains precipitated and the liquid which became cloudy was obtained. By suction filtration, particles were collected using a glass filter.

Next, a silicone stopper was placed at the outlet of the glass filter to prevent the solvent placed in the filter from leaking out, then 150 parts of methanol was added, and after holding for 30 minutes in a state in which the particles were completely immersed, the silicone stopper was removed and the liquid was taken out. . This operation was repeated twice. The second time, suction filtration was performed until the liquid stopped coming out. In this way, the resin composition containing resin and a solvent was obtained.

The amount of organic solvent in the obtained composition was measured by the gas chromatography method, and the water content was measured by the Karl Fischer method, respectively.

As shown in Table 1, in the resin composition (b) obtained by the manufacturing method of this invention, the residual amount of the alcohol solvent was reduced. When the said resin composition was dried at 200 degreeC over 3 hours, polyimide-type resin powder was obtained. The residual amount of solvent (mass reduction rate at 200 to 300°C) of the polyimide-based resin powder after drying is 0.08%, and the chromaticity is L*=97.83, a*=- in the color difference measurement based on the L*a*b* color system. 2.96, b*=7.94, and the particle size distribution was D ₁₀ =174 _{µm, D 50} =225 µm, and D ₉₀ =284 µm. On the other hand, in the resin composition obtained by the manufacturing method of Comparative Example 1, there is very much content of an alcohol-type solvent, for example, in patent document 1, in order to avoid the fall and coloring of the heat resistance of a film, polyimide-type resin powder It required drying at the temperature of less than 100 degreeC until the volatile component in it became about less than 5 %. Therefore, according to the manufacturing method of this invention, it was confirmed that it is possible to efficiently remove alcoholic solvents, such as methanol.

Claims (12)

(1) A polyimide-based resin solution in which a polyimide-based resin is dissolved in a good solvent is brought into contact with a solvent containing an alcohol having 1 to 4 carbon atoms to precipitate a polyimide-based resin, and the precipitated polyimide-based resin is included the process of obtaining a mixture,
(2) solid-liquid separation of the obtained mixture, the process of obtaining the polyimide-type resin composition (a) containing the polyimide-type resin which precipitated, and;
(3) The step of bringing the polyimide-based resin composition (a) into contact with a solvent containing water as a main component
A method for producing a polyimide-based resin powder comprising at least a. The method of claim 1,
A manufacturing method, wherein the chromaticity of the polyimide-based resin powder satisfies L*≥90, -10≤a*≤10, and -10≤b*≤10 in color difference measurement based on the L*a*b* color system. . 3. The method according to claim 1 or 2,
The polyimide-type resin contains a fluorine atom, the manufacturing method. 4. The method according to any one of claims 1 to 3,
The polyimide-based resin is an aromatic polyimide-based resin. 5. The method according to any one of claims 1 to 4,
The polyimide resin has an imidization ratio of 90% or more. 6. The method according to any one of claims 1 to 5,
In the step (3), if the mass of the polyimide-based resin composition (a) is W ₁ , and the mass of the solvent mainly composed of water to be brought into contact with the polyimide-based resin composition (a) is W ₂ , W the ratio of W ₂ to ₁ (W ₂ / W ₁₎ is at least 4, and the contact time is 10 minutes or more, a manufacturing method. 7. The method according to any one of claims 1 to 6,
After step (3),
(4) A manufacturing method including the process of carrying out solid-liquid separation and obtaining a polyimide-type resin composition (b). 8. The method of claim 7,
Content of water in the said polyimide-type resin composition (b) is 10 mass % or more with respect to the total mass of the said polyimide-type resin composition (b), and content of a C1-C4 alcohol is the said polyimide The manufacturing method which is less than 3 mass % with respect to the total mass of a mid-type resin composition (b). 9. The method according to any one of claims 1 to 8,
The manufacturing method which further includes the process (X) of obtaining the mixture containing the polyimide-type resin which made the mixture obtained by the process (1), and the solvent containing water contact, before the process (2), and precipitated polyimide-type resin. 10. The method according to any one of claims 1 to 9,
The manufacturing method which further includes the process (Y) of making a C1-C4 alcohol contact the polyimide-type resin composition (a) obtained in the process (2) before a process (3). A polyimide-based resin composition containing at least a polyimide-based resin and water, wherein the content of water in the polyimide-based resin composition is 10% by mass or more with respect to the total mass of the polyimide-based resin composition, and the number of carbon atoms The polyimide-type resin composition whose content of the alcohol of 1-4 is less than 3 mass % with respect to the total mass of the said polyimide-type resin composition. 12. The method of claim 11,
The polyimide-type resin composition whose content of a C1-C4 alcohol is 0.001 mass % or more with respect to the total mass of a polyimide-type resin composition.