KR20210093183A - Method for producing polyamide-based resin powder - Google Patents

Abstract

The present invention provides a method for preparing polyamide-based powder, which allows efficient preparation of polyamide-based resin powder having a small particle diameter and a small deviation in particle diameter. The method for preparing polyamide-based powder includes at least a contacting step in which a polyamide-based resin solution (a) including a polyamide-based resin dissolved in a good solvent for the polyamide-based resin is in contact with a poor solvent solution (b) including at least one poor solvent for the polyamide-based resin. In the method, when the area of the supply interface in the contacting step is taken as X m^2, and the addition rate of the polyamide-based resin solution (a) or poor solvent solution (b) is taken as Y kg/min, the addition flow rate defined by formula (A) of [Addition flow rate ((kg/min)/m^2) = Y/X] is 400 or less.

Description

The manufacturing method of polyamide-type resin powder {METHOD FOR PRODUCING POLYAMIDE-BASED RESIN POWDER}

The present invention relates to a method for producing a polyamide-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 applications 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 for various purposes. Although various things are mentioned as resin which has flexibility, For example, there exist a polyamide-type resin and a polyimide-type resin.

When a member such as a front plate is manufactured using a polyamide-based resin and a polyimide-based resin, powders of these resins are used for ease of handling. For example, the polyimide powder which has a specific average particle diameter and can obtain the film whose light transmittance in 450 nm is 80 % or more is disclosed by patent document 1.

International Publication No. 2017/179367

In examining a method for producing polyamide-based resin powder, the present inventors, in the drying step for producing polyamide-based resin powder, have a small particle size and a small polyamide-based resin powder with a small variation in particle size, The drying time becomes short, and it is difficult to produce non-uniformity in drying, and the dissolution process at the time of manufacturing an optical film using polyamide-type resin powder, for example, a varnish manufacturing process WHEREIN: Dissolution time becomes short, and dissolution nonuniformity I found that this was difficult to happen. For example, patent document 1 describes the manufacturing method of polyimide powder which adds the poor solvent of a polyimide to a polyimide solution, precipitates a polyimide, and forms powder. However, according to the study of the present inventors, it was found that in the case of polyamide-based resins, polyamide-based resin powder having a small particle size and a small variation in particle size could not be obtained in some cases depending on the conditions for adding a poor solvent and the like.

Accordingly, it is an object of the present invention to provide a method for producing a polyamide-based resin powder that is easy to efficiently produce a polyamide-based resin powder having a small particle size and a small variation in particle diameter.

MEANS TO SOLVE THE PROBLEM In order to solve the said subject, this inventor paid attention to the addition method of a poor solvent, and conducted earnest examination. As a result, by a method for producing a polyamide-based resin powder comprising contacting a polyamide-based resin solution (a) in which a polyamide-based resin is dissolved in a good solvent with a poor solvent under specific conditions, the above problems found to be solved, and came to complete the present invention.

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

[1] A poor solvent solution comprising a polyamide-based resin solution (a) in which a polyamide-based resin is dissolved in a good solvent for the polyamide-based resin, and at least one poor solvent for the polyamide-based resin ( b) includes at least a contacting step of contacting, wherein the area of the supply interface region in the contacting step is X m 2 , and the addition rate of the polyamide-based resin solution (a) or poor solvent solution (b) is Y kg In /min, Equation (A):

Addition flow rate ((kg/min)/m2) = Y/X Formula (A)

The addition flow rate calculated by the method for producing a polyamide-based resin powder is 400 or less.

[2] The production method according to [1], wherein the contacting step is performed by adding the poor solvent solution (b) to the polyamide-based resin solution (a).

[3] In the contacting step, when the poor solvent solution (b) is added to the polyamide-based resin solution (a), the stirring power of the polyamide-based resin solution (a) is Z kW/m 3 , and the polyamide-based resin solution (a) is When the system resin solution (a) is added to the poor solvent solution (b), if the stirring power of the poor solvent solution (b) is Z kW/m 3 , the formula (B):

Ratio R=(Y/X)/Z Formula (B)

The production method according to [1] or [2], wherein the ratio R of the addition flow rate to the stirring power calculated by is 300 or less.

[4] the contact process, the rate and R is each containing a different first contacting step and the second contacting step at least, the ratio of R ₁ in the first contacting step, the more the ratio R ₂ of the second contact step A small, production method according to any one of [1] to [3].

[5] The manufacturing method according to the above [4], _{wherein the ratio R 1} in the first contacting step is 150 or less.

[6] The production method according to any one of [1] to [5], wherein the polyamide-based resin solution (a) has a viscosity of 0.5 to 100 Pa·s.

[7] The production method according to any one of [1] to [6], wherein the polyamide-based resin is selected from the group consisting of a polyamide resin and a polyamideimide resin.

[8] In the contacting step, the polyamide-based resin solution (a) or the poor solvent solution (b) is added using at least one selected from the group consisting of a spray, a dripping nozzle, a shower, and a nozzle dispersion plate. The production method according to any one of [1] to [7], which is performed.

[9] The production method according to [8], wherein the addition is performed using a spray.

[10] The production method according to any one of [1] to [9], wherein the polyamide-based resin solution (a) further contains at least one poor solvent.

_{[11] A poor solvent solution comprising a polyamide-based resin solution (a 0} ) in which a polyamide-based resin is dissolved in a good solvent for the polyamide-based resin, and at least one poor solvent for the polyamide-based resin The production method according to [10], further comprising a step of contacting (b _{0 ) to obtain the polyamide-based resin solution (a).}

[12] In the step of obtaining the polyamide-based resin solution (a _{), the area of the supply interface region when the polyamide-based resin solution (a 0} ) and the poor solvent solution (b ₀ ) are brought into contact is P m 2 , When the addition rate of the polyamide-based resin solution (a ₀ ) or the poor solvent solution (b ₀ ) is Q kg/min, the formula (C):

Addition flow rate ((kg/min)/m2) = Q/P formula (C)

The production method according to [11], wherein the addition flow rate calculated by

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the polyamide-type resin powder which a particle diameter is small and it is easy to manufacture the polyamide-type resin powder with small dispersion|variation in particle diameter can be provided.

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

In the method for producing polyamide-based resin powder of the present invention (hereinafter also referred to as “the production method of the present invention”), a polyamide-based resin solution in which the polyamide-based resin is dissolved in a good solvent for the polyamide-based resin (a) and at least a contacting step of contacting the polyamide-based resin with a poor solvent solution (b) containing at least one poor solvent, wherein the area of the supply interface region in the contacting step is X m2 and the addition rate of the polyamide-based resin solution (a) or poor solvent solution (b) is Y kg/min, the formula (A):

Addition flow rate ((kg/min)/m2) = Y/X Formula (A)

The addition flow rate calculated by is 400 or less, including the contact process.

The production method of the present invention includes at least a contact step of bringing the polyamide-based resin solution (a) into contact with the poor solvent solution (b), and the addition flow rate in the contact step is 400 or less.

(Polyamide-based resin solution (a))

The polyamide-based resin solution (a) is a solution in which the polyamide-based resin is dissolved in a good solvent. Here, in the present specification, the polyamide-based resin refers to at least one kind of resin selected from the group consisting of polyamide resins, polyamideimide resins, and polyamideimide precursor resins. A polyamide resin is a resin containing a repeating structural unit containing an amide group, and a polyamideimide resin is a resin containing a repeating structural unit containing both an amide group and an imide group. Moreover, polyamide-imide precursor resin is a precursor before imidation which provides polyamide-imide resin by imidation, and is resin also called polyamic acid. In this specification, the said polyamideimide precursor resin is also called "polyamic acid resin."

The polyamide-based resin solution (a) may be, for example, a reaction solution obtained by polymerizing a raw material monomer of a polyamide-based resin in a solvent (particularly, a good solvent for a polyamide-based resin), or an isolated The solution obtained by dissolving polyamide-type resin in a good solvent may be sufficient, and the solution obtained by further adding a poor solvent to these solutions may be sufficient. From the viewpoint of being easy to efficiently carry out the process from the synthesis of the polyamide-based resin to the production of the polyamide-based resin powder, the polymerization reaction of the monomers is performed in a good solvent to be described later, and the resulting reaction solution is converted to a polyamide-based resin solution. It is preferable to use as (a), or to use the solution obtained by adding a poor solvent to the obtained reaction solution as polyamide-type resin solution (a).

The good solvent contained in the polyamide-based resin solution (a) is a solvent that easily dissolves the polyamide-based resin, and for example, has a solubility in the polyamide-based resin at room temperature (20 to 30°C) of 1% by mass or more. refers to the solvent. One type of solvent may be sufficient as the good solvent contained in the polyamide-type resin solution, and the mixture of 2 or more types of solvent may be sufficient as it. As the good solvent, for example, acetone, N,N-dimethylformamide (sometimes described as DMF), dimethyl sulfoxide (sometimes described as DMSO), γ-butyrolactone (described as GBL) In some cases), N,N-dimethylacetamide (it may be described as DMAc), etc. are mentioned. In addition, whether the solvent to be used is a good solvent can be confirmed by the following method. Polyamide-based resin is added to the solvent so as to be 1% by mass, and if necessary, the resin is dissolved in the solvent by heating and stirring, etc., and when the solution at room temperature (20 to 30° C.) becomes 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, a solvent was measured and taken in a container, stirred, a polyamide-based resin was put thereto to be 1 mass %, and the mixture was stirred at room temperature (24°C) for 3 hours. As a result, when there is no dissolution residue and the solution is uniformly transparent, it is a good solvent, and when a dissolution residue exists, it can be judged not as a good solvent but as a poor solvent.

The solubility of the good solvent in the polyamide-based resin is preferably 3% by mass or more, more preferably 5% by mass or more from the viewpoint of volumetric efficiency. Although the upper limit of the solubility with respect to the polyamide-type resin of a good solvent is not specifically limited, From a viewpoint that the usage-amount of a poor solvent can be reduced, Preferably it is 40 mass % or less, More preferably, it is 25 mass % or less. In addition, in the present specification, the solubility of a certain solvent S in the polyamide-based resin is defined as solubility (%) = G/(G+H) when the amount of the polyamide-based resin soluble in the solvent S in G parts by mass is H parts by mass. It is a value calculated by the formula of x100.

When the polyamide-based resin solution (a) contains a good solvent and does not contain a poor solvent, the content of the good solvent in the polyamide-based resin solution (a) is adjusted to a viscosity that is easy to handle in terms of operation From the viewpoint of ease of use, it is preferably 60 mass % or more, more preferably 75 mass % or more, with respect to the total amount of the polyamide-based resin solution. In addition, the content of the good solvent in the polyamide-based resin solution is preferably 98% by mass or less, more preferably 95% by mass or less, based on the total amount of the polyamide-based resin solution, from the viewpoint that the amount of the poor solvent can be reduced. mass% or less.

When the polyamide-based resin solution (a) contains a good solvent and does not contain a poor solvent, the content of the polyamide-based resin in the polyamide-based resin solution (a) is determined from the viewpoint of volumetric efficiency. Preferably it is 1 mass % or more with respect to the total amount of an amide-type resin solution, More preferably, it is 3 mass % or more. In addition, the content of the polyamide-based resin in the polyamide-based resin solution is preferably 20 mass% or less with respect to the total amount of the polyamide-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.

When the polyamide-based resin solution (a) further contains at least one poor solvent, the content of the good solvent in the polyamide-based resin solution (a) is adjusted to a viscosity that is easy to handle in terms of operation. From the viewpoint of ease, it is preferably 40 mass % or more, more preferably 50 mass % or more, still more preferably 60 mass % or more with respect to the total amount of the polyamide-based resin solution (a). In addition, the content of the good solvent in the polyamide-based resin solution (a) is preferably 95% by mass or less with respect to the total amount of the polyamide-based resin solution (a) from the viewpoint that the amount of the poor solvent can be reduced. , More preferably, it is 90 mass % or less.

When the polyamide-based resin solution (a) further contains at least one poor solvent, the content of the polyamide-based resin in the polyamide-based resin solution (a) is, from the viewpoint of volumetric efficiency, polyamide Preferably it is 1 mass % or more with respect to the total amount of a system resin solution, More preferably, it is 2 mass % or more. In addition, the content of the polyamide-based resin in the polyamide-based resin solution is preferably 20 mass% or less with respect to the total amount of the polyamide-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.

When the polyamide-based resin solution (a) further contains at least one poor solvent, the poor solvent may be one solvent or a mixture of two or more solvents. The poor solvent in the present specification is a solvent in which the polyamide-based resin is hardly dissolved, for example, a solvent having a solubility in the polyamide-based resin at room temperature (20 to 30°C) of less than 1 mass%. Examples of the poor solvent include alcohol solvents such as methanol and 2-propanol (eg, alcohols having 1 to 4 carbon atoms), ethyl acetate, tetrahydrofuran, toluene, hexane, and water. In addition, the evaluation method of whether the solvent to be used is a poor solvent is as mentioned above. In this case, the polyamide resin solution (a) may further contain one type of poor solvent, and may further contain the mixed solvent of 2 or more types of poor solvents.

The poor solvent contained in the polyamide-based resin solution (a) is preferably a poor solvent containing an alcohol having 1 to 4 carbon atoms. Examples of the alcohol having 1 to 4 carbon atoms include methanol, ethanol, 2-propanol and butanol. The poor solvent contained in the polyamide-based resin solution (a) 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 or more types of alcohols having 1 to 2 carbon atoms. A mixture of the alcohol of 4 and other poor solvents may be used.

When the polyamide-based resin solution (a) further contains at least one poor solvent, the content of the poor solvent in the polyamide-based resin solution (a) should be adjusted to a viscosity that is easy to handle in terms of operation. From the viewpoint of being easy and easy to efficiently produce a polyamide-based resin powder having a small particle size and a small particle size variation, preferably 5% by mass or more, more preferably, with respect to the total amount of the polyamide-based resin solution. is 10 mass% or more, more preferably 15 mass% or more. Moreover, content of the poor solvent in polyamide-type resin solution (a) is easy to prevent precipitation of polyamide-type resin in polyamide-type resin solution (a), and from a viewpoint of improving production efficiency, Preferably it is 40 mass % or less with respect to the total amount of an amide-type resin solution, More preferably, it is 30 mass % or less.

When the polyamide-based resin solution (a) further contains at least one poor solvent, in the production method of the present invention, the polyamide-based resin is dissolved in a good solvent for the polyamide-based resin. resin solution (a ₀₎ and, by contacting the poor solvent solution (b ₀₎ containing at least a poor solvent of one kind of the polyamide-series resin further includes a step for obtaining the polyamide resin solution (a) You can do it. In the step of obtaining the polyamide-based resin solution (a _{), the area of the supply interface region when the polyamide-based resin solution (a 0} ) and the poor solvent solution (b ₀ ) are brought into contact is P m 2 , When the addition rate of the resin solution (a ₀ ) or the poor solvent solution (b ₀ ) is Q kg/min, the formula (C):

Addition flow rate ((kg/min)/m2) = Q/P formula (C)

Although the addition flow rate calculated by this is not specifically limited, From a viewpoint of being easy to raise production efficiency, Preferably it exceeds 400.

The amount of the precipitated polyamide-based resin contained in the polyamide-based resin solution (a) is a polyamide-based resin powder having a small particle size and a small variation in particle size in the subsequent contacting step with the poor solvent solution (b) or the like. From the viewpoint of being easy to efficiently produce, based on the total amount of the polyamide-based resin contained in the polyamide-based resin solution (a), preferably 10% by mass or less, more preferably 5% by mass or less, still more preferably preferably 3 mass % or less, even more preferably 1 mass % or less, particularly preferably 0 mass %. In addition, the amount of the precipitated polyamide-based resin contained in the polyamide-based resin solution (a) is obtained by measuring the mass of the obtained solid by separating the polyamide-based resin solution (a) into solid-liquid by filtration or the like. lose Moreover, the quantity of the polyamide-type resin which precipitated contained in polyamide-type resin solution (a) may be the quantity measured in the temperature which performs a contact process with poor solvent liquid (b). 0 mass % of the amount of the precipitated polyamide-based resin contained in the polyamide-based resin solution (a) indicates that no polyamide-based resin has precipitated in the polyamide-based resin solution (a).

From the viewpoint of facilitating the production of a polyamide-based resin powder having a small particle size and a small variation in particle size through a contact step of bringing the polyamide-based resin solution (a) into contact with the poor solvent solution (b), which will be described later, , it is particularly important to adjust the addition flow rate before, after, and after that point, based on the time point at which the polyamide-based resin powder starts to precipitate. Therefore, in the polyamide-type resin solution (a) before making the poor solvent liquid (b) contact, it is preferable that precipitation of polyamide-type resin does not arise. In addition, from the same viewpoint, when the polyamide-based resin solution (a) does not contain a poor solvent or contains a poor solvent, the amount of the poor solvent contained in the polyamide-based resin solution (a) is , with respect to the amount of the poor solvent contained in the mixture obtained after the contacting step (the mixture before the solid-liquid separation step), preferably 60 mass% or less, more preferably 50 mass% or less, still more preferably 45 mass% or less do.

The viscosity of the polyamide-based resin solution (a) is determined depending on the content of the polyamide-based resin in the polyamide-based resin solution (a), the molecular weight of the polyamide-based resin, etc. 0.5 Pa·s or more, more preferably 0.6 Pa·s or more, still more preferably 0.7 Pa·s or more, easy to handle in operation, small in particle size, and small in particle size variation. From the viewpoint of easiness to manufacture the powder, it is preferably 100 Pa·s or less, more preferably 50 Pa·s or less, still more preferably 10 Pa·s or less. The viscosity can be measured using a viscometer, for example, under the measurement conditions described in Examples.

(Poor solvent (b))

In the contacting step included in the production method of the present invention, the polyamide-based resin solution (a) and the poor solvent solution (b) are brought into contact. The poor solvent solution (b) is a solvent containing at least one type of poor solvent, may be one type of poor solvent, or may be a mixed solvent of two or more types of poor solvents, and may be a poor solvent solution (b) with respect to the polyamide-based resin. As long as the mixed solvent as ) shows poor solvent property, the mixed solvent containing one or more types of poor solvent and a good solvent may be sufficient. Examples of the poor solvent include alcohol solvents such as methanol and 2-propanol (eg, alcohols having 1 to 4 carbon atoms), ethyl acetate, tetrahydrofuran, toluene, hexane, and water. In addition, the evaluation method of whether the solvent to be used is a poor solvent is as above-mentioned.

The poor solvent solution (b) to be brought into contact with the polyamide-based resin solution (a) is preferably a solvent containing water, and more preferably a solvent containing 70 mass% or more of water. When the poor solvent solution (b) contains water, the ratio is the total amount of the poor solvent solution (b) from the viewpoint of easy removal of the good solvent or alcohol, which may be contained in the polyamide-based resin as the case may be precipitated. preferably 30 mass % or more, more preferably 40 mass % or more, still more preferably 50 mass % or more, still more preferably 60 mass % or more, particularly preferably 70 mass % or more, more particularly Preferably it is 75 mass % or more, Especially more preferably, it is 80 mass % or more, Especially preferably, it is 85 mass % or more, More preferably, it is 90 mass % or more. In addition, the content of the alcohol contained in the poor solvent solution (b) is preferably 20 mass% or less, more preferably 10 mass% or less, still more preferably 5% by mass or less with respect to the total mass of the poor solvent solution (b). It is mass % or less, More preferably, it is 3 mass % or less.

(contact process)

The production method of the present invention includes at least a contact step of bringing the polyamide-based resin solution (a) into contact with the poor solvent solution (b), and the addition flow rate in the contact step is 400 or less. In the production method of the present invention, the contacting step of bringing the polyamide-based resin solution (a) into contact with the poor solvent solution (b) may be a one-step contacting step or two or more contacting steps. Here, that the contact process is two or more steps means that there are two or more different steps in the stirring rate, the addition rate, the type of the poor solvent used, and the like.

When the contact process of bringing the polyamide-based resin solution (a) into contact with the poor solvent solution (b) is two or more steps, the polyamide-based resin solution (a) having an addition flow rate of 400 or less and the poor solvent solution (b) are brought into contact What is necessary is just to include a process at least.

The method for bringing the polyamide-based resin solution (a) into contact with the poor solvent solution (b) is not particularly limited as long as they are in contact. For example, the poor solvent solution (b) is added to the polyamide-based resin solution (a). The method of adding or the method of adding the polyamide-type resin solution (a) to the poor solvent solution (b) is mentioned. From the viewpoint of easily obtaining a powder having a small particle size and a small particle size variation, the polyamide-based resin solution (a) and the poor solvent solution (b) are brought into contact with the polyamide-based resin solution (a) with the poor solvent solution. It is preferable to carry out by adding (b). Moreover, it is more preferable to perform addition by dripping from a viewpoint of being easy to adjust an addition rate. By the said contact, a polyamide-type resin precipitates, and the mixture containing the polyamide-type resin which precipitated is obtained. Further, in the mixture containing the deposited polyamide-based resin, at least a part of the polyamide-based resin dissolved in the polyamide-based resin solution may be deposited.

As for the addition flow rate in the contacting step, the area of the supply interface region in the contacting step is X m 2 , and the addition rate of the polyamide-based resin solution (a) or poor solvent solution (b) is Y kg/min. , Equation (A):

Addition flow rate ((kg/min)/m2) = Y/X Formula (A)

is calculated by In the contact process included in the manufacturing method of this invention, the said addition flow rate is 400 or less.

The area (X m 2 ) of the supply interface region in the contacting step is determined by the polyamide-based resin solution (a) being supplied to the poor solvent solution (b), or the poor solvent solution (b) being the polyamide-based resin solution ( It is the area of the area of the interface where the first contact in each of these contacting steps occurs by being supplied to a). The addition (supply) of the polyamide-based resin solution (a) or the poor solvent solution (b) is preferably performed using at least one selected from the group consisting of a spray, a dripping nozzle, a shower, and a nozzle dispersion plate. . For example, when the above contacting step is performed by supplying the poor solvent solution (b) to the polyamide-based resin solution (a), the poor solvent solution (b) is supplied from, for example, one or a plurality of nozzles. It may be supplied, may be supplied using a nozzle having a plurality of branches, may be supplied using one or a plurality of showers and sprays, or may be supplied by a method of attaching a dispersion plate to the tip of the nozzle. As a spray, For example, Ikeuchi Corporation's full cone nozzle JJXP, multiple head nozzle 7JJXP, wide angle full cone nozzle BBXP, angular fan nozzle VP, eccentric equalization fan nozzle INOVVE, (Note) ) The poor solvent solution (b) can be supplied using the fan-shaped nozzle NZRVF etc. made by MISUMI. As a shower, the poor solvent liquid (b) can be supplied using, for example, SANEI Co., Ltd. product shower head S1040F1, rotary shower head S1040F5, etc. When the above contacting step is performed by supplying the polyamide-based resin solution (a) to the poor solvent solution (b), the polyamide-based resin solution (a) is supplied from the nozzle or the like.

For example, when supply is performed using one nozzle having one discharge port, the inner diameter cross-sectional area of the discharge port is referred to as the area of the supply interface region. When supply is performed using one nozzle having two or more discharge ports, the sum of the inner diameter cross-sectional areas of all the discharge ports provided in the nozzle is referred to as the area of the supply interface region. When supply is performed using two or more nozzles having one or two or more discharge ports, in the same manner as in the case of using one nozzle, the supply interface area for each nozzle is calculated, and the sum of these is calculated as the area of the supply interface region. It is said Also in the case of using a shower, the sum of the inner diameter cross-sectional areas of all the discharge ports provided in one or two or more showers is referred to as the area of the supply interface region. In the case of using a spray, since the spray has a function of being spread over a wide area from the discharge port, the area of distribution of the supply liquid is referred to as the area of the supply interface region. In other words, when supply is performed using one or two or more dripping nozzles and/or showers, the sum of the inner diameter cross-sectional areas of all the discharge ports provided in the dripping nozzles and/or shower is called the area of the supply interface region, and spray is used In the case where the supply is performed, the dispersion area in which the ejection liquid discharged from the spray is dispersed on the supply interface is referred to as the area of the supply interface region. In the case of using the nozzle dispersion plate, the dispersion area discharged from the nozzle dispersion plate is referred to as the area of the supply interface region. Here, for example, when supply is performed using two or more nozzles and the supply interface region of each nozzle overlaps in part or all of the region, the overlap is calculated from the sum of the areas of each supply interface region. The area excluding the area of the region to be used is called the area of the supply interface region. Even when two or more showers, sprays, or the like are used, if overlapping regions exist, the area of the supply interface region is calculated in the same manner.

In the case of using a spray nozzle, the lower limit of the ratio (supply interface area/negative cross-sectional area) of the feed interface area and the negative cross-sectional area is preferable from the viewpoint of easily obtaining a powder with a small particle size and a small particle size variation. Preferably, it is 0.1 or more, More preferably, it is 0.2 or more, It is preferable to supply under the conditions which become 0.25 or more more preferably. Thereby, rapid precipitation and coarsening of particle|grains becomes easy to be suppressed. Although the upper limit of the said ratio is not specifically limited, From a viewpoint of being easy to handle in operation, Preferably it is 0.9 or less, More preferably, it is 0.7 or less, More preferably, it is 0.5 or less, More preferably, it is 0.45 or less.

The addition rate Y (kg/min) is, for example, when the contact step is performed by adding the poor solvent solution (b) to the polyamide-based resin solution (a), the poor solvent solution ( It can be calculated by dividing the amount of b) by the time required for the addition of the poor solvent solution (b). When the contacting step is performed by adding the polyamide-based resin solution (a) to the poor solvent solution (b), the amount of the polyamide-based resin solution (a) added in the contacting step is adjusted to the polyamide-based resin solution ( It can be calculated by dividing by the time required for the addition of a). When the contacting step includes two or more steps different in the addition rate, the addition flow rate in at least one step may be 400 or less, but a weight calculated as a weighted average based on the amount of the poor solvent added in each step It is preferable that the addition flow rate calculated using the average addition rate Y is 400 or less.

When the addition flow rate (Y/X) computed by said formula exceeds 400, it is easy to produce a part with a high concentration of a poor solvent locally. Moreover, a change in the concentration of the poor solvent tends to occur rapidly. When the concentration of the poor solvent becomes too high locally, the polyamide-based resin powder is rapidly precipitated locally, the polyamide-based resin powder is precipitated together with impurities, or the solidified polyamide-based resin contains a solvent. , it becomes difficult to obtain fine powder. It becomes difficult to obtain fine powder also by a poor solvent density|concentration becoming high rapidly. Moreover, as a result, the dispersion|variation in a particle diameter also becomes easy to produce. When the addition flow rate (Y/X) calculated by the above formula is 400 or less, it is possible to obtain a powder having a small particle size and a small variation in particle size. The addition flow rate is preferably 400 or less, more preferably 300 or less, still more preferably 100 or less, and still more preferably 80 or less from the viewpoint of easiness of obtaining such a powder. Although the lower limit of the addition flow rate (Y/X) is not specifically limited, From a viewpoint of being easy to raise production efficiency, Preferably it is 0.1 or more, More preferably, it is 0.5 or more, More preferably, it is 1.0 or more.

The addition may be performed continuously or may be performed intermittently. When the addition is performed intermittently, the addition flow rate may be calculated using the addition rate of the step in which the addition is being performed.

The above addition flow rate is determined by adjusting the addition rate (Y kg/min) and the area of the supply interface region (X m 2 ) in the contact step of bringing the polyamide-based resin solution (a) into contact with the poor solvent solution (b). , can be adjusted to the desired range. The addition rate is computed by dividing the quantity of the poor solvent liquid (b) added in the contact process by the time required for addition as mentioned above, and can be adjusted by adjusting the addition amount and addition time. The area (X m 2 ) of the supply interface region is determined by a method of adjusting the inner diameter cross-sectional area and number of the nozzles to be used, and in addition to these when using a spray nozzle, a method of adjusting the height of the spray nozzle from the supply interface and a method of adjusting the discharge pressure, etc. can be adjusted by

When the contacting step includes two or more steps having different addition flow rates, the addition flow rate (Y/X) in at least one step may be 400 or less. It is preferable that the average addition flow rate calculated as a weighted average based on the amount of the poor solvent is 400 or less. Also about the average addition flow rate in this case, the preferable description regarding the said addition flow rate and a preferable numerical range also apply.

In the contacting step, usually, when adding the poor solvent solution (b) to the polyamide-based resin solution (a), the polyamide-based resin solution (a) is added to the poor solvent while stirring the polyamide-based resin solution (a). When adding to liquid (b), a contact process is performed, stirring poor solvent liquid (b). Here, when the poor solvent solution (b) is added to the polyamide-based resin solution (a), the stirring power of the polyamide-based resin solution (a) is Z kW/m 3 , and the polyamide-based resin solution (a) is In the case of adding to the poor solvent solution (b), if the stirring power of the poor solvent solution (b) is Z kW/m3, the formula (B):

Ratio R=(Y/X)/Z Formula (B)

The ratio R of the addition flow rate to the stirring power calculated by is preferably 300 or less, more preferably 150 or less, still more preferably 100 or less, and still more preferably 50 or less. Moreover, the ratio R becomes like this. Preferably it is 1 or more, More preferably, it is 2 or more, More preferably, it is 3 or more. When the ratio R is less than or equal to the upper limit, the variation in particle size becomes small, and when the ratio R is equal to or greater than the lower limit, the production efficiency can be easily improved.

Agitation power (Z [㎾/m3]) is given by the formula (D):

Z = Np × ρ × (n/60) ³ × d ⁵ /V/1000 Formula (D)

is calculated by

(In formula (D), Np represents the number of power, ρ represents the liquid density [kg/m3], n represents the stirring rotation speed [rpm], d represents the blade diameter of the stirring blade [m] , and V represents the volume of liquid [m3].)

The power number Np can be obtained from the correlation between the power number Np and the Reynolds number Re described in the previous literature formulas or manufacturer catalogs, and the Reynolds number Re is obtained by formula (E)

Re = ρ × n/60 × d ² /μ Equation (E)

(in formula (E), μ represents the liquid viscosity [Pa s], ρ represents the liquid density [kg/m 3], n represents the number of stirring rotations [rpm], and d is the blade diameter of the stirring blade [ m])

is calculated by

For example, in this example, a 3-blade retracted blade is used, and the Np-Re diagram described on page 8 of the catalog "Glasslined Reactor" (No. 114E, Printed in Japan Mar. 2018) of Shinko Environmental Solutions Co., Ltd. ((3) Oval Section Three-blades retreat impeller with beaver-tail baffle, see https://www.kobelco-eco.co.jp/product/process/punf_pdf/p_glasslinedreactor.pdf) .

As a method of adjusting stirring power and adjusting the ratio R, the method of adjusting the number of stirring rotations and the method of changing the volume of a liquid are mentioned.

It is preferable that the said contacting process includes at least the 1st contacting process and the 2nd contacting process in which the ratio R differs from each other. In this case, the ratio R ₁ of the first contact step is also preferably smaller than the ratio R ₂ of the second contacting step. In this case, the ratio R ₁ in the first contact step is preferably 150 or less, more preferably 100 or less, still more preferably 50 or less, from the viewpoint of reducing the variation in particle size. It is 1 or more, More preferably, it is 2 or more, More preferably, it is 3 or more. Further, the ratio R ₂ in the second contact step is preferably 300 or less, more preferably 150 or less, still more preferably 100 or less, and preferably 2 or more, from the viewpoint of increasing production efficiency. More preferably, it is 3 or more, More preferably, it is 5 or more.

(solid-liquid separation process)

Through said contacting process, the mixture containing the polyamide-type resin which precipitated, a good solvent, and a poor solvent at least is obtained. By solid-liquid separation of the said mixture, polyamide-type resin powder is obtained. Further, by solid-liquid separation of the mixture obtained through the contacting step, a polyamide-based resin composition containing the precipitated polyamide-based resin contained in the mixture and a part of the solvent contained in the mixture can be obtained. The said polyamide-type resin composition is a composition also called a wet cake, and is an intermediate body for obtaining polyamide-type resin powder.

The method of solid-liquid separation is not particularly limited, for example, a method generally called filtration, specifically, a method of separating by gravity through a filter having different permeability of precipitates and solvents, a method of separating by centrifugal force, A method of separating by a pressure difference is exemplified. As an example of the filter which can be used, a centrifugal filter, a drug filter filter, a suction filter, a vacuum filter, etc. are mentioned.

(drying process)

The production method of the present invention may further include a drying step of drying the polyamide-based resin composition to obtain polyamide-based resin powder. Drying conditions are not particularly limited as long as the solvent in the polyamide-based resin composition is removed, and for example, under reduced pressure or atmospheric pressure, heating at a temperature of about 50 to 250° C. for about 1 to 48 hours. do. From the viewpoint of increasing 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. .

< Polyamide-based resin powder >

The polyamide-based resin powder produced by the production method of the present invention is ^L* ≥90, -10≤a in the ^{measurement of color difference based on the L*} a ^* b ^* colorimetric system (based on JIS Z 8781-4:2013). ^* ≤ 10, and -10 ≤ b ^* ≤ 10 are preferably satisfied. ^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 increasing 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 is preferably -10 or more and 10 or less, more preferably -7 or more and 7 or less, from the viewpoint of showing an index of redness and easy to increase the visibility of the finally obtained polymer material; More preferably, they are -5 or more and 5 or less. ^{b *} in the color difference measurement is preferably -10 or more and 10 or less, more preferably -5 or more and 10 or less, from the viewpoint of showing an index of bluishness and increasing the visibility of the finally obtained polymer material; More preferably, they are -3 or more and 7 or less. The color difference may be measured using a color difference meter. According to the manufacturing method of this invention, when polyamide-type resin powder precipitates, it can suppress that the impurity etc. contained in the polyamide-type resin solution are contained in a precipitate. Therefore, according to the manufacturing method of this invention, it is easy to manufacture the polyamide-type resin powder which has the above color difference values.

_{The median diameter (d 50} ) in the volume-based particle size distribution obtained for the polyamide-based resin powder produced by the production method of the present invention is the drying of the powder when the powder is produced. From the viewpoint of ease of preparation and solubility of the powder when producing a polymer material using the powder, preferably 10 to 1,000 µm, more preferably 50 to 800 µm, still more preferably 100 to 600 µm, More preferably, it is 200-500 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.

_{From d 10} , d ₅₀ and d ₉₀ in the volume-based particle size distribution obtained for the polyamide-based resin powder produced by the production method of the present invention, the formula (F):

δ=(d ₉₀ -d ₁₀ )/d ₅₀ Formula (F)

The parameter δ calculated by is preferably 5.0 or less, more preferably 4.5 or less, still more preferably 4.0 or less, still more preferably 3.0 or less, particularly preferably 1.5 or less, even more particularly preferably 1.0 or less. am. Here, d _x represents the particle size at which the frequency (accumulated volume from the small diameter side) becomes x% in the obtained particle size distribution, and the smaller the parameter δ, the smaller the particle size variation. When the parameter δ is equal to or less than the upper limit described above, it is easy to reduce unevenness in drying powder when producing the powder and dispersion in solubility of powder when producing a polymer material using the powder.

< Polyamide-based resin >

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

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

[Formula 1]

[In formula (1), Y represents a tetravalent organic group, X represents a divalent organic group, and * represents a bond. In formula (2), Z and X each independently represent a divalent organic group, and * represents a bond.]

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 a preferred embodiment of the present invention in which the polyamide-based resin is an aromatic polyamide-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 one 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 formula (2), Z represents a divalent organic group, Preferably, a C1-C6 alkyl group, a C1-C6 alkoxy group, or a C6-C12 aryl group (The hydrogen atom in these groups is halogen atom, preferably a divalent organic group having 4 to 40 carbon atoms which may be substituted by a fluorine atom), more preferably an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms. , or an aryl group having 6 to 12 carbon atoms (a hydrogen atom in these groups may be substituted with a halogen atom, preferably a fluorine atom). represents an organic group. In addition, the fit alkoxy group of the alkyl group having 1 to 6 carbon atoms, 1 to 6 carbon atoms, or examples of the aryl group having a carbon number of 6 to 12, an example of the R ^3a and R ^3b in the formula (3) to be described later containing the same manner. Examples of the cyclic structure include an alicyclic ring, an aromatic ring, and a heterocyclic structure. 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 Equation (29):

[Formula 2]

[In Formulas (20) to (29), 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-, wherein Ar represents, independently of each other, an arylene group having 6 to 20 carbon atoms in which a hydrogen atom may be substituted with a fluorine atom ( For example, it represents a phenylene group), and * represents a bond]

Among the bonds of the group represented by , a group in which two non-adjacent groups are substituted with hydrogen atoms and a divalent chain hydrocarbon group having 6 or less carbon atoms are exemplified, and the heterocyclic structure of Z includes a group having a thiophene ring skeleton. From the viewpoint of easily suppressing the yellowness of the polyamide-based resin powder and the resulting optical member (reducing the YI value), groups represented by formulas (20) to (29) and groups having a thiophene ring skeleton are preferable. and groups represented by formulas (26), (28) and (29) are more preferable.

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 3]

[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 hydrogen atom on the ring in Formulas (20) - Formula (29) and Formula (20') - Formula (29') is a C1-C6 alkyl group, a C1-C6 alkoxy group, or a C6 to 12 aryl groups (a hydrogen atom in these groups may be substituted with a halogen atom (preferably a fluorine atom)) may be substituted.

In the polyamide-based resin, when Z in Formula (2) has a structural unit represented by any of Formulas (20') to (29'), Z in Formula (2) is a formula ( When it has a structural unit represented by 3'), the polyamide-based resin has the following formula (d1) in addition to the structural unit:

[Formula 4]

[In formula (d1), R ²⁴ is a group or a hydrogen atom defined for ^{R 3a} in formula (3) to be described later ^{, R 25} represents R ²⁴ or -C(=O)-*, and * is a bond. represents]

It is preferable from a viewpoint that it is easy to improve the film-forming property of a varnish, and it is easy to improve the uniformity of an optical film to further have the structural unit derived from the carboxylic acid represented by. Specifically, the structural unit (d1) is 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 (=O The structural unit (structural unit derived from a tricarboxylic acid compound) etc. which represent )-* are mentioned.

Polyamide-type resin may contain multiple types of Z as Z in Formula (2), and multiple types of Z may mutually be same or different. From the viewpoint of easily improving the bending resistance and impact resistance of the optical film obtained by using the polyamide-based resin powder of the present invention and increasing the optical properties, Z in the formula (2) is preferably the formula (3) :

[Formula 5]

[In formula (3), R ^3a and R ^3b each independently represent 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 are included in ^{R 3a} and R ^3b The hydrogen atoms to be formed may be each independently substituted with a halogen atom,

W 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,

s is an integer from 0 to 4, t is an integer from 0 to 4, u is an integer from 0 to 4, * represents a bond]

, more preferably the formula (3'):

[Formula 6]

[in formula (3'), R ^3a , R ^3b , s, t, u, W and * are as defined in formula (3)]

It is preferable to have at least a structural unit represented by In addition, in the present specification, the polyamide-based resin has a structural unit in which Z in the formula (2) is represented by the formula (3), and the polyamide-based resin is represented by the formula (3) as Z in the formula (2), It has the same meaning, and Z in at least some structural units among the structural units represented by formula (2) contained in the polyamide-based resin is represented by formula (3). it means. The description also applies to other similar descriptions.

In formulas (3) and (3'), W 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 )-, from the viewpoint of bending resistance of the optical film, preferably represents -O- or -S-, more preferably -O-.

R ^3a and R ^3b each independently represent 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, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, 2 -methyl-butyl group, 3-methylbutyl group, 2-ethyl-propyl group, n-hexyl group, etc. are mentioned. Examples of the alkoxy group having 1 to 6 carbon atoms include methoxy group, ethoxy group, propyloxy group, isopropyloxy group, n-butoxy group, isobutoxy group, sec-butoxy group, tert-butoxy group, n-pene A tyloxy group, n-hexyloxy group, cyclohexyloxy group, etc. are mentioned. 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 surface hardness and flexibility of the optical film, R ^3a and R ^3b each independently represent an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms. Here, ^{the hydrogen atoms contained in R 3a} and R ^3b may be each independently 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, isobutyl group, sec-butyl group, tert-butyl group, n-pene. Tyl group, 2-methyl-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-de A real group etc. are mentioned, These may be substituted by the halogen atom. A fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc. are mentioned as said halogen atom.

t and u in formulas (3) and (3') are each independently an integer of 0 to 4, preferably an integer of 0 to 2, more preferably 0 or 1, still more preferably 0 .

s in Formula (3) and Formula (3') is an integer in the range of 0-4, and when s is in this range, the bending resistance and elasticity modulus of the film containing the said polyamide-type resin will become favorable easily. s in formulas (3) and (3') is preferably an integer in the range of 0 to 3 from the viewpoint of more easily improving the impact resistance, elastic modulus, and bending resistance of the film containing the polyamide-based resin. , more preferably an integer in the range of 0 to 2, more preferably 0 or 1, even more preferably 0. The structural unit containing the structure represented by Formula (3) or Formula (3') in which s is 0 as Z in Formula (2) is, for example, a structural unit derived from terephthalic acid or isophthalic acid, and the structural unit is preferably a structural unit including a structure in which s is 0 and u is 0 in Formula (3) or Formula (3'). From a viewpoint of being easy to improve the impact resistance of an optical film, an elastic modulus, and bending resistance, it is preferable that polyamide-type resin contains the structural unit derived from terephthalic acid. Polyamide-type resin may contain the structural unit 1 type(s) or 2 or more types of Z is represented by Formula (3) or Formula (3'). From a viewpoint of being easy to reduce the yellowness of polyamide-type resin powder and the optical member obtained, and from a viewpoint of being easy to improve the impact resistance, elastic modulus, and bending resistance of an optical film, polyamide-type resin is Z in Formula (2) As such, it is preferable to include two or more types of structures having different values of s in Formula (3) or Formula (3'), and two or 3 structures having different values of s in Formula (3) or Formula (3'). It is more preferable to include a kind of structure. In this case, from the viewpoint of being easy to increase the impact resistance, elastic modulus, and bending resistance of an optical film, and from a viewpoint of being easy to reduce the yellowness of polyamide-type resin powder and the optical film obtained, polyamide-type resin is Formula (2) As Z in the structural unit represented by , the structure represented by the formula (3) in which s is 0, in addition to the structural unit containing the structure, the structure represented by the formula (3) in which s is 1 It is more preferable to further contain a structural unit comprising Moreover, in addition to the structural unit represented by Formula (2) which has Z represented by Formula (3) where s is 0, it is also preferable to further have a structural unit represented by said Formula (d1).

In one preferred embodiment of the present invention, the polyamide-based resin has a structure (divalent group) represented by Formula (3) or Formula (3'), in which s=0 and u=0 . In one more preferred embodiment of the present invention, the polyamide-based resin has a structure represented by Formula (3) or Formula (3'), wherein s=0 and u=0, and Formula (3" ):

[Formula 7]

It has a structure represented by In this case, while it is easy to improve the impact resistance of an optical film, an elastic modulus, and bending resistance, it is easy to reduce the yellowness of polyamide-type resin powder and an optical film.

When Z in Formula (2) has a structural unit represented by Formula (3) or Formula (3') in a polyamide-type resin, the ratio is a structural unit represented by Formula (1) of a polyamide-type resin. And when the total of the structural units represented by formula (2) is 100 mol%, preferably 20 mol% or more, more preferably 30 mol% or more, still more preferably 40 mol% or more, even more preferably is 50 mol% or more, particularly preferably 60 mol% or more, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less. Z in Formula (2) is easy to improve the impact resistance of an optical film, elasticity modulus, and bending resistance as the ratio of the structural unit represented by Formula (3) or Formula (3') is more than said minimum. When Z in Formula (2) is the ratio of the structural unit represented by Formula (3) or Formula (3') is below the said upper limit, the viscosity of the resin containing varnish by the hydrogen bond between amide bonds derived from Formula (3) rises. suppression, and it is easy to improve the workability of the film.

Moreover, when polyamide-type resin has a structure represented by Formula (3) or Formula (3') which is s=1-4 as Z in Formula (2), s is Formula (3) or Formula (3) which is 1-4 The ratio of the structural unit represented by Formula (2) having Z represented by (3') is the sum of the structural unit represented by Formula (1) and the structural unit represented by Formula (2) of the polyamide-based resin. When referring to 100 mol%, it is preferably 3 mol% or more, more preferably 5 mol% or more, still more preferably 7 mol% or more, even more preferably 9 mol% or more, and preferably 90 mol% or more. or less, more preferably 70 mol% or less, still more preferably 50 mol% or less, still more preferably 30 mol% or less. When the ratio of the structural unit represented by Formula (2) having Z represented by Formula (3) or Formula (3') where s is 1-4 is at least the above lower limit, the impact resistance, elastic modulus and bending resistance of the optical film easy to raise Formula (3) or Formula (3') as long as the ratio of the structural unit represented by Formula (2) having Z represented by Formula (3) or Formula (3') where s is 1-4 is below the said upper limit The increase in the viscosity of the resin-containing varnish due to hydrogen bonding between amide bonds derived from the structure represented by is suppressed, and the workability of the film is easily improved. In addition, the ratio of the structural unit in which Z in Formula (1), Formula (2), Formula (2) is represented by Formula (3) or Formula (3') is ^{measured using 1} H-NMR, for example. Alternatively, it can be calculated from the introduction ratio of the raw material.

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, even more preferably 50 mol% or more of Z in the polyamide-based resin. mol% or more is represented by Formula (3) or Formula (3') where s is 0-4. When more than the said lower limit of Z is represented by Formula (3) or Formula (3') where s is 0-4, it will be easy to improve the impact resistance, an elastic modulus, and bending resistance of an optical film. Moreover, 100 mol% or less of Z in polyamide-type resin should just be represented by Formula (3) or Formula (3') whose s is 0-4. In addition, the ratio of the structural unit represented by Formula (2) which has Z represented by Formula (3) where s is 0-4 or Formula (3') in resin uses ¹ H-NMR, for example. can be measured, or it can be calculated from the introduction ratio of the raw material.

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, even more preferably 12 mol% or more of Z in the polyamide-based resin mol% or more is represented by Formula (3) or Formula (3') where s is 1-4. When more than the said lower limit of Z of polyamide-type resin is represented by Formula (3) or Formula (3') whose s is 1-4, it is easy to improve the impact resistance, elasticity modulus, and bending resistance of an optical film. Further, preferably 90 mol% or less of Z, more preferably 70 mol% or less, still more preferably 50 mol% or less, still more preferably 30 mol% or less is the formula ( It is represented by 3) or Formula (3'). When less than or equal to the above upper limit of Z is represented by Formula (3) or Formula (3') wherein s is 1-4, s is derived from a structure represented by Formula (3) or Formula (3') where 1-4 is suppresses the increase in the viscosity of the resin-containing varnish due to hydrogen bonding between the amide bonds of In addition, the ratio of the structural unit represented by Formula (2) which has Z represented by Formula (3) or Formula (3') in which s is 1-4 in resin is, for example, ^{using <1>} H-NMR. It can be measured, or it can also be computed from the introduction ratio of a raw material.

In formulas (1) and (2), X is, independently of each other, a divalent organic group, preferably a divalent organic group having 4 to 40 carbon atoms, more preferably a C4 to C40 cyclic structure It represents a divalent organic group. Examples of the cyclic structure include an alicyclic ring, an aromatic ring, and a heterocyclic structure. 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 the present invention, the polyamide-based resin of the present invention may contain a plurality of types of X, and the plurality of types of X may be the same as or different from each other. As X, group represented by Formula (10), Formula (11), Formula (12), Formula (13), Formula (14), Formula (15), Formula (16), Formula (17) and Formula (18) ; a group in which a hydrogen atom in the groups represented by the 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 8]

[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, independently of each other, with respect to each ring, preferably meta position or para position, more preferably is the para position.

Among the groups represented by formulas (10) to (18), from the viewpoint of being easy to increase the impact resistance, elastic modulus, and bending resistance of the optical film, formulas (13), (14), (15), and (16) ) and the group represented by Formula (17) are 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 each independently from the viewpoint of increasing the impact resistance, elastic modulus, and flexibility of the optical film, preferably a single bond, -O- or -S-, more preferably It is a single bond or -O-.

In one preferred embodiment of the present invention, the polyamide-based resin is X in Formula (1) or X in Formula (2), Formula (4):

[Formula 9]

[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 by a halogen atom, and * represents a bond]

It has a structure represented by It is easy to raise the impact resistance of an optical film, elasticity modulus, and transparency as at least one part of X in the some structural unit represented by Formula (1) and Formula (2) is a structure represented by Formula (4).

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. of 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 Examples of 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 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 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 the impact resistance, elastic modulus, transparency and bending resistance of the optical film, Even more 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 , particularly preferably R ¹¹ and R ¹⁷ represent a methyl group or a trifluoromethyl group.

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

[Formula 10]

It is a structural unit represented by , ie, at least a part of X in a 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 polyamide-type resin by frame|skeleton containing the element fluorine, and being easy to improve the storage stability of the varnish containing the said resin, it is easy to reduce the viscosity of the said varnish, and an optical film It is easy to improve the workability of Moreover, it is easy to improve the optical characteristic of an optical film by frame|skeleton containing a fluorine element.

In a preferred embodiment of the present invention, X in the polyamide-based resin is preferably 30 mol% or more, more preferably 50 mol% or more, and 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 polyamide-based resin is represented by Formula (4), particularly Formula (4'), the resulting optical film has an improved solubility in the solvent of the resin due to the skeleton containing elemental fluorine, While it is easy to improve the storage stability of the varnish containing the said resin, it is easy to reduce the viscosity of the said varnish, and it is easy to improve the workability of an optical film. Moreover, the optical characteristic of an optical film is also easy to improve by frame|skeleton containing a fluorine element. Moreover, Preferably, 100 mol% or less of X in the said polyamide-type resin is represented by Formula (4), especially Formula (4'). X in the said resin may be Formula (4), especially Formula (4') may be sufficient as it. 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, From a viewpoint of being easy to raise impact resistance and an elastic modulus, Preferably, an aromatic ring is 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 the present invention, the polyamide-based resin is a polyamide-imide resin, and the polyamide-imide resin may contain a plurality of types of Y, and the plurality of types of Y may be the same or different from each other. As Y, Formula (20), Formula (21), Formula (22), Formula (23), Formula (24), Formula (25), Formula (26), Formula (27), Formula (28) and Formula the 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 chain hydrocarbon group having 6 or less carbon atoms.

[Formula 11]

In formulas (20) to (29), * represents a bond, W ¹ represents 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), groups represented by formulas (26), (28) or (29) from the viewpoint of easily increasing the impact resistance, elastic modulus, and bending resistance of the optical film It is preferable, and the group represented by Formula (26) is more preferable. In addition, W ^1, the impact resistance of the optical film, the elastic modulus, and in increasing the bending resistance with ease, the perspective is likely to reduce the yellowness of the polyamide resin powder, and the optical film, independently from each other, preferably a single bond , -O-, -CH ₂ -, -CH ₂ -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ -, more preferably a single bond , -O-, -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ -, more preferably a single bond, -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ -, even more preferably a single bond or -C(CF ₃ ) ₂ -.

In one preferred embodiment of the present invention, preferably 50 mol% or more, more preferably 60 mol% or more, still more preferably 70 mol% or more of Y in the polyamideimide resin is represented by the formula (26) is indicated In the polyamideimide resin, Y within the above range is the formula (26), preferably the formula (26), ^{wherein W 1} is a single bond, -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ -, more Preferably, when W ¹ is a single bond or -C(CF ₃ ) ₂ - represented by Formula (26), it is easy to increase the impact resistance, elastic modulus, and bending resistance of the optical film, and polyamide-based resin powder and optical film It is easy to reduce the yellowness of The ratio of the structural unit in which Y is represented by Formula (26) in the polyamideimide resin ^{can be measured, for example, using 1} H-NMR, or can be calculated from the introduction ratio of the raw material.

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

[Formula 12]

[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, and R ¹⁸ to ^{R 25} The hydrogen atoms contained in may be each independently substituted by a halogen atom, and * represents a bond]

and/or formula (9)

[Formula 13]

[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 by a halogen atom, and * represents a bond]

is represented by When at least a part of Y in some formula (1) is represented by Formula (5) and/or is represented by Formula (9), it will be easy to improve the impact resistance of an optical film, an elastic modulus, and an optical characteristic.

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, or 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, wherein 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 each independently more preferably from the viewpoint of easily increasing the impact resistance, elastic modulus, and bending resistance of the optical film, and from the viewpoint of easiness of increasing transparency and maintaining the transparency of the optical film, more preferably represents a hydrogen atom, a methyl group, a fluoro group, a chloro group or a trifluoromethyl group, 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 represents a hydrogen atom, a methyl group, a fluoro group, a chloro group or a trifluoromethyl group, particularly preferably R ²¹ and R ²² represent a methyl group or a trifluoromethyl group.

In formula according to (9), is chemically stable, easy to increase the impact resistance, elastic modulus and flex resistance, along with point of view, and, increasing the ease of transparency of the optical film, it is easy to maintain the art transparency viewpoint, R ³⁵ ~R ⁴⁰ Silver 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, further preferably a hydrogen atom. Here, ^{the hydrogen atoms contained in R 35} to ^{R 40} may be each independently 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. there is. 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 formula (5) is represented by the formula (5'), and the formula (9) is the formula (9'):

[Formula 14]

is represented by That is, at least a part of some Y is represented by Formula (5') and/or Formula (9'). In this case, it is easy to improve the impact resistance, elasticity modulus, and bending resistance of an optical film. In addition, when formula (5) is represented by formula (5'), the solubility of the polyamide-based resin in a solvent is increased by the skeleton containing elemental fluorine, and the storage stability of the varnish containing the resin is easily improved. Together with this, it is easy to reduce the viscosity of the said varnish and it is easy to improve the workability of an optical film. Moreover, it is easy to improve the optical characteristic of an optical film by frame|skeleton containing a fluorine element.

In one preferred embodiment of the present invention, the amount of Y in the polyamideimide resin is preferably 50 mol% or more, more preferably 60 mol% or more, and still more preferably 70 mol% or more of Y in the formula (5), In particular, it is represented by Formula (5'). When Y within the above range in the polyamideimide resin is represented by the formula (5), particularly the formula (5'), the solubility of the polyamide-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 an optical film. Moreover, it is easy to improve the optical characteristic of an optical film by frame|skeleton containing a fluorine element. Moreover, Preferably, 100 mol% or less of Y in the said polyamideimide resin is represented by Formula (5), especially Formula (5'). Y in the polyamideimide resin may be a formula (5), particularly a formula (5'). The ratio of the structural unit represented by the formula (5) of Y in the polyamideimide resin ^{can be measured, for example, using 1} H-NMR, or can be calculated from the introduction ratio of the raw material.

In one preferred embodiment of the present invention, the plurality of structural units represented by the formula (1) is, in addition to the structural unit represented by the formula (5), Y is a structural unit represented by the formula (9) It is preferable to further include. When Y further contains the structural unit represented by Formula (9), it is easy to improve the impact resistance and elastic modulus of an optical film further.

The polyamideimide resin may include a structural unit represented by Formula (30) and/or a structural unit represented by Formula (31), and may be represented by Formula (1) and optionally Formula (2), The structural unit represented by Formula (30) and/or the structural unit represented by Formula (31) other than a structural unit may be included.

[Formula 15]

In Formula (30), Y<^1> represents a tetravalent organic group, Preferably the hydrogen atom in the organic group represents the organic group which may be substituted by the hydrocarbon group or the fluorine-substituted hydrocarbon group. As Y ^1, Formula (20), Formula (21), Formula (22), Formula (23), Formula (24), Formula (25), Formula (26), Formula (27), Formula (28) and Formula ( 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 and chain hydrocarbon groups. In one embodiment of the present invention, the polyamide-based resin may include a plurality of types of Y ^1, Y ¹ of a plurality of species may be the same or different from each other.

In the formula (31), Y ² represents a trivalent organic, and preferably represents an organic group which may be substituted by a hydrogen atom of a hydrocarbon group or a fluorine-substituted hydrocarbon group in the organic group. As Y ² , Formula (20), Formula (21), Formula (22), Formula (23), Formula (24), Formula (25), Formula (26), Formula (27), Formula (28) and 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, polyamide-imide resins, may include a plurality of types of Y ^2, Y ² is a plurality of types may be the same or different from each other.

In Formulas (30) and (31), X ¹ and X ² each independently represent 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. represents an organic group. X ¹ and X ² as in the formula 10, formula 11, formula 12, formula 13, formula 14, formula 15, formula 16, formula 17 and formula ( 18); a group in which a hydrogen atom in the groups represented by the 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 polyamide-based resin is a structural unit represented by Formula (1) and/or Formula (2), and optionally, Formula (30) and/or Formula (31) made up of constituent units. In addition, from the viewpoint of being easy to improve the optical properties, impact resistance, elastic modulus, and bending resistance of the optical film, in the polyamide-based resin, the ratio of the structural units represented by the formulas (1) and (2) is, Based on the total structural units represented by 1) and formulas (2), and optionally 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 a polyamide-type resin, the ratio of the structural unit represented by Formula (1) and Formula (2) is Formula (1) and Formula (2), and Formula (30) and/or Formula ( 31), 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 polyamide-based resin in the base layer contained in the optical film is preferably 10 parts by mass or more, more preferably 10 parts by mass or more with respect to 100 parts by mass of the base layer constituting the optical film. Preferably it is 30 mass parts 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 the content of the polyamide-based resin is within the above range, it is easy to adjust the thickness of the intermediate layer of the optical film to be within the above range, and it is easy to improve bending resistance, and it is easy to improve the optical properties, impact resistance and elastic modulus of the optical film.

The weight average molecular weight of the polyamide-based resin is preferably in terms of standard polystyrene, from the viewpoint of easily adjusting the thickness of the intermediate layer of the optical film within the above range, and from the viewpoint of increasing the impact resistance, elastic modulus and bending resistance. is 200,000 or more, more preferably 230,000 or more, still more preferably 250,000 or more, even more preferably 270,000 or more, particularly preferably 280,000 or more. In addition, the weight average molecular weight of the polyamide-based resin is preferably from the viewpoint of more easily increasing the solubility of the polyamide-based resin powder during varnish preparation, and from the viewpoint of easily improving the stretchability and workability of the optical film. 1,000,000 or less, more preferably 800,000 or less, still more preferably 700,000 or less, even more preferably 500,000 or less. The weight average molecular weight can, for example, be measured by gel permeation chromatography (hereinafter sometimes referred to as GPC) and can be calculated in terms of standard polystyrene, for example, even if calculated by the method described in the Examples. do.

In one preferred embodiment of the present invention, when the polyamide-based resin is a polyamide-imide resin, the content of the structural unit represented by the formula (2) in the polyamide-imide resin is To 1 mol of the structural unit, preferably 0.1 mol or more, more preferably 0.5 mol or more, still more preferably 1.0 mol or more, still more preferably 1.5 mol or more, preferably 6.0 mol or less, more preferably is 5.0 mol or less, more preferably 4.5 mol or less. It will be easy to raise the impact resistance and elastic modulus of an optical film as content of the structural unit represented by Formula (2) is more than the said minimum. Moreover, the thickening by the hydrogen bond between the amide bonds in Formula (2) is suppressed as content of the structural unit represented by Formula (2) is below the said upper limit, and it is easy to improve the workability of an optical film.

In a preferred embodiment of the present invention, the polyamide-based resin may contain a halogen atom such as a fluorine atom, which can be introduced by, for example, the fluorine-containing substituent described above. When the polyamide-based resin contains a halogen atom, the elastic modulus of the optical film is improved, and the yellowness of the polyamide-based resin powder and the optical film is easily reduced. When the elastic modulus of an optical film is high, it will be easy to suppress generation|occurrence|production, such as a flaw and a wrinkle. Moreover, when the yellowness of an optical film is low, it will become easy to improve the 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 polyamide-type resin contain a fluorine atom, a fluoro group and a trifluoromethyl group are mentioned, for example.

The content of halogen atoms in the polyamide-based resin is preferably 1 to 40% by mass, more preferably 5 to 40% by mass, still more preferably 5 based on the mass of the polyamide-based resin, respectively. -30% by mass. When content of a halogen atom is more than the said lower limit, the elasticity modulus of an optical film is improved more, water absorption is lowered, and the yellowness of polyamide-type resin powder and an optical film is further reduced, and transparency and visibility are easy to improve more. It becomes easy to synthesize|combine that content of a halogen atom is below the said upper limit.

The imidation ratio of the polyamideimide resin is preferably 90% or more, more preferably 93% or more, still more preferably 96% or more. From a viewpoint of being easy to raise the optical characteristic of an optical film, it is preferable that imidation ratio is more than said lower limit. Moreover, the upper limit of the imidation ratio is 100 % or less. The imidation ratio represents the ratio of the molar amount of the imide bond to a value twice the molar amount of the structural unit derived from the tetracarboxylic acid compound in the polyamideimide resin. In addition, when the polyamideimide resin contains a tricarboxylic acid compound, a value twice the molar amount of the structural unit derived from the tetracarboxylic acid compound in the polyamideimide resin and the structural unit derived from the tricarboxylic acid compound The ratio of the molar amount of the imide bond in the polyamideimide resin to the sum of the molar amount is shown. In addition, the imidation rate can be calculated|required by IR method, NMR method, etc.

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

< Manufacturing method of resin >

A polyamide resin can be manufactured using a diamine compound and a dicarboxylic acid compound as main raw materials, for example. Polyamideimide resin and polyamideimide precursor resin can be manufactured using, for example, a tetracarboxylic acid compound, a dicarboxylic acid compound, and a diamine compound as main raw materials. Here, it is preferable that a dicarboxylic acid compound contains the compound represented by Formula (3") at least.

[Formula 16]

[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 The ^{hydrogen atoms included in 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 represents} -, -S-, -CO- or -N(R ⁹ )-;

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, an isobutoxy group, a sec-butoxy group, a tert-butoxy group or chlorine atom.]

In one preferred embodiment of the present invention, the dicarboxylic acid compound is a compound represented by the formula (3″) in which m is 0. As the dicarboxylic acid compound, the dicarboxylic acid compound is represented by the formula (3″) in which m is 0. In addition to the compound, it is more preferable to use a compound represented by the formula (3") wherein A is an oxygen atom. In another preferred embodiment, in the dicarboxylic acid compound, R ³¹ and R ³² are chlorine It is a compound represented by Formula (3") which is an atom. 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 mentioned, It is not limited to these. Among these, a benzene ring is preferable. Moreover, the "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'- Diaminodiphenylsulfone, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]sulfone, bis [4-(3-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl] Propane, 2,2'-dimethylbenzidine, 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 Aromatic diamines having two or more aromatic rings, such as -chlorophenyl)fluorene and 9,9-bis(4-amino-3-fluorophenyl)fluorene, are mentioned. These can be used individually or in combination of 2 or more types.

The aromatic diamine is preferably 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether , 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 1,4-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl] Sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy) ) phenyl] propane, 2,2'-dimethylbenzidine, TFMB, and 4,4'-bis(4-aminophenoxy)biphenyl, more preferably 4,4'-diaminodiphenylmethane; 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylsulfone, 1,4-bis(4-aminophenoxy)benzene, bis[4 -(4-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-dimethylbenzidine, TFMB, 4,4'-bis(4- aminophenoxy) biphenyl. These can be used individually or in combination of 2 or more types.

Among the 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 modulus of elasticity, 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 one or more types selected from the group, and it is still more preferable to use 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 tetracarboxylic acid compound analogs other than dianhydride, such as an acid chloride compound.

As a specific example of aromatic tetracarboxylic dianhydride, non-condensed polycyclic aromatic tetracarboxylic dianhydride, monocyclic aromatic tetracarboxylic dianhydride, and condensed polycyclic aromatic tetracarboxylic dianhydride are mentioned. 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 (sometimes referred to as BPDA), 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 acid 2 Anhydride (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 and 3-dicarboxyphenyl)methane dianhydride, 4,4'-(p-phenylenedioxy)diphthalic dianhydride, and 4,4'-(m-phenylenedioxy)diphthalic dianhydride. Moreover, as monocyclic aromatic tetracarboxylic dianhydride, 1,2,4,5-benzenetetracarboxylic dianhydride is mentioned, for example, As condensed polycyclic aromatic tetracarboxylic dianhydride, for example, For example, 2,3,6,7-naphthalenetetracarboxylic dianhydride is mentioned.

Among these, 4,4'-oxydiphthalic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,2',3,3'-benzophenonetetracarboxylic acid 2 Anhydride, BPDA, 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, 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 are mentioned, More preferably, 4,4'-oxydiphthalic acid 2 Anhydride, BPDA, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 6FDA, bis(3,4-dicarboxyphenyl)methane dianhydride and 4,4'-(p-phenylenedioxy) Diphthalic acid dianhydride is mentioned. These can be used individually or in combination of 2 or more types.

As aliphatic tetracarboxylic dianhydride, cyclic or acyclic aliphatic tetracarboxylic dianhydride is mentioned. Cyclic aliphatic tetracarboxylic dianhydride is tetracarboxylic dianhydride having an alicyclic hydrocarbon structure, and specific examples thereof include 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 1,2,3,4-cyclo Cycloalkanetetracarboxylic dianhydride such as butanetetracarboxylic dianhydride and 1,2,3,4-cyclopentanetetracarboxylic dianhydride, bicyclo[2.2.2]oct-7-ene-2,3,5 and 6-tetracarboxylic dianhydride, dicyclohexyl-3,3',4,4'-tetracarboxylic dianhydride, and regioisomers thereof. These can be used individually or in combination of 2 or more types. Specific examples of the acyclic aliphatic tetracarboxylic dianhydride include 1,2,3,4-butanetetracarboxylic dianhydride and 1,2,3,4-pentanetetracarboxylic dianhydride. 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, from the viewpoint of high impact resistance, high modulus of elasticity, high surface hardness, high transparency, high flexibility, high bending resistance, and low coloration of the optical film, more preferably 4,4'-oxydiphthalic acid dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, BPDA, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 3,3',4,4' -diphenylsulfonetetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 6FDA, and mixtures thereof, more preferably BPDA and 6FDA, and their mixtures, and more preferably 6FDA and BPDA.

As a dicarboxylic acid compound used for manufacture of resin, Preferably terephthalic acid, isophthalic acid, 4,4'- oxybisbenzoic acid, or those acid chloride compounds are used. In addition to terephthalic acid, isophthalic acid, 4,4'-oxybisbenzoic acid or their acid chloride compounds, other dicarboxylic acid compounds may be used. Examples of other dicarboxylic acid compounds include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and their derivative acid chloride compounds, acid anhydrides, and the like, and may be used in combination of two or more. 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 by a single bond, -CH ₂ -, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, -SO ₂ -, or a phenylene group linked compounds and their acid chloride compounds. As a specific example, 4,4'-oxybis(benzoyl chloride) (it may be described as OBBC), terephthaloyl chloride (it may be described as TPC) or isophthaloyl chloride is preferable, and OBBC and TPC are combined It is more preferable to use

In addition, in addition to the said tetracarboxylic acid compound, the polyamideimide 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 film.

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, those flexible acid chloride compounds, an acid anhydride, etc. are mentioned, You may use in combination of 2 or more type. Specific examples thereof include anhydrides of 1,2,4-benzenetricarboxylic acid; anhydride of 1,3,5-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 polyamide-type resin.

Although the reaction temperature of a diamine compound, a tetracarboxylic acid compound, and a dicarboxylic acid compound is not specifically limited in manufacture of resin, For example, 5-350 degreeC, Preferably it is 20-200 degreeC, More preferably, 25 ∼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. Moreover, 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, GBL, 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 DMAc and DMF; sulfur-containing solvents such as dimethyl sulfone, DMSO, 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 polyamideimide 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 anhydride and butyric anhydride, and aromatic acid anhydrides such as phthalic acid.

The polyamide-based resin may be 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, and may be isolated. , in a preferred embodiment, can be isolated by adding a large amount of alcohol such as methanol to a reaction solution containing a transparent polyamide-based resin, depositing the resin, and performing concentration, filtration, drying, and the like.

The polyamide-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 the window film which is a front plate of a flexible display. A single layer may be sufficient as an optical member, and a multilayer 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 the polyamide-based resin powder produced by the production method of the present invention is used as an optical member, the content of the polyamide-based resin in the optical member is preferably 40% by mass or more with respect to the total mass of the optical member. , more preferably 50 mass % or more, still more preferably 70 mass % or more, still more preferably 80 mass % or more, especially 90 mass % or more. The bending resistance of an optical member is favorable as the content rate of a polyamide-type resin is more than the said lower limit. In addition, the content rate of the polyamide-type resin in an optical member is 100 mass % or less normally with respect to the total mass of an optical member.

(Inorganic material)

The optical member may further contain an inorganic material such as inorganic particles other than the polyamide-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 polyamide-based resin for producing an optical member, the inorganic material is preferably inorganic particles, particularly silica particles. The 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. 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 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. The ultraviolet absorber can be appropriately selected from those commonly used as ultraviolet absorbers in the field of resin materials. The ultraviolet absorber may contain a compound that absorbs light having a 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. When an optical member contains a ultraviolet absorber, since deterioration of polyamide-type resin is suppressed, 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" was 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 appropriate 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 is improved and an optical member with high transparency can be obtained. .

(Other additives)

The optical member may contain another additive further. As other components, 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.

When other additives are contained, the content rate is preferably 0.001 mass % or more and 20 mass % or less, and more preferably 0.001 mass % or more and 10 mass % or less with respect to the mass of the optical member.

For example, although the thickness of the optical member which is an optical film is suitably adjusted according to a use, Usually 10-1,000 micrometers, Preferably it is 15-500 micrometers, More preferably, it is 20-400 micrometers, More preferably, it is 25-300 micrometers. μm. In addition, in this invention, thickness can be measured with a contact type "digital indicator".

In the optical member, the total light transmittance Tt based on JIS K 7105:1981 is preferably 70% or more, more preferably 80% or more, still more preferably 85% or more, still more preferably 90% or more. % or more When the optical member is assembled into 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. In addition, the upper limit of the total light transmittance Tt of an optical member is 100 % or less normally. 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. , more preferably 0.3% or less. When the haze of an optical member is below the said upper limit, when assembling an optical member to flexible electronic devices, such as an image display apparatus, sufficient visibility will be easy to ensure. In addition, the lower limit of the said haze is not specifically limited, What is necessary is just 0 % or more. The polyamide-based resin dissolved in the polyamide-based resin solution (a) used in the production method of the present invention, and/or the polyamide-based resin powder obtained by the production method of the present invention, has the total light transmittance Tt and It is desirable to have/or haze. The total light transmittance Tt and/or haze of the polyamide-based resin and the polyamide-based resin powder are measured from the shape of a molded body (eg, 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 polyamide-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 polyamide-based resin powder in a solvent and applying a solution containing a polyamide-based resin (polyamide-based resin varnish) to a substrate (application step), and

(b) Drying the applied liquid (polyamide-based resin varnish) to form an optical member (preferably an optical film or polyamide-based resin film) (forming process)

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

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

The solvent used for preparation of a varnish will not be specifically limited if polyamide-type resin can be melt|dissolved. Examples of such solvents include amide solvents such as DMAc and DMF; lactone-based solvents such as GBL and γ-valerolactone; sulfur-containing solvents such as dimethyl sulfone, DMSO, 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. Moreover, water, an alcohol solvent, a ketone solvent, an acyclic ester solvent, an ether solvent, etc. may be contained in a varnish.

Next, for example, using a varnish of a polyamide-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.

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, the coating film may be dried under an inert atmosphere or under reduced pressure.

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

Examples of the resin substrate include a PET film, a PEN film, a polyamide film, and a polyamideimide film. Among them, PET film, PEN film, polyamide 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 polyamide-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, still more preferably 6.0 GPa or more, and preferably It is preferably 10.0 GPa or less. 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. The elastic modulus is, for example, using Autograph AG-IS manufactured by Shimadzu Corporation, 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. Measure a stress-strain line, It can be measured from the slope. The polyamide-based resin dissolved in the polyamide-based resin solution (a) used in the production method of the present invention, and/or the polyamide-based resin powder obtained by the production method of the present invention, has the above elastic modulus. desirable. The elastic modulus of the polyamide-based resin and the polyamide-based resin powder is measured from the shape of a molded body (eg, a film). The detail of the preparation method of a measurement sample and a measurement method is as described in an Example.

The optical member has excellent bending resistance. In a suitable embodiment of the present invention, the optical member has a number of reciprocating bending until fracture when measured at a speed of 175 cpm with a load of 0.75 kgf and a load of 0.75 kgf at 135° at R=1 mm, preferably 10,000 or more, more preferably 20,000 or more, still more preferably 30,000 or more, even more preferably 40,000 or more, particularly preferably 50,000 or more.

If the number of times of reciprocating bending of the optical member is equal to or more than the above lower limit, it is possible to further suppress wrinkles that may occur when the optical member is bent. 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 reciprocating bending can be calculated|required using the 50-micrometer-thick, 10-mm-width test piece (optical member) with the MIT folding fatigue tester (model 0530) made by Toyo Seiki Seisakusho Co., Ltd. product, for example. The polyamide-based resin dissolved in the polyamide-based resin solution (a) used in the production method of the present invention and/or the polyamide-based resin powder obtained by the production method of the present invention have the above bending resistance. it is preferable The bending resistance of the polyamide-based resin and the polyamide-based resin powder is measured from the shape of a molded body (eg, a film).

The optical member may exhibit excellent transparency. Therefore, the said optical member is very useful as an image display apparatus, especially as a window film. In a suitable embodiment of the present invention, the optical member has a yellowness YI based on JIS K7373:2006, preferably 5 or less, more preferably 3 or less, still more preferably 2.5 or less, still more preferably is less than 2.0. The optical member whose yellowness YI is below the said upper limit can contribute to high visibility, such as a display apparatus. Moreover, the yellowness of the said optical member becomes like this. Preferably it is 0 or more. The polyamide-based resin dissolved in the polyamide-based resin solution (a) used in the production method of the present invention, and/or the polyamide-based resin powder obtained by the production method of the present invention, has the above yellowness YI. It is preferable to have The yellowness YI of the polyamide-based resin and the polyamide-based resin powder is measured from the shape of a molded article, for example, a film.

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 polyamide-type resin powder of this invention, for example, an optical film is useful as a front plate of an image display apparatus, especially a window film. The optical member may be disposed as a front plate on the viewer-side surface of an image display device, particularly 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 other members, and also the optical member itself also produces a wrinkle. It is difficult, and scratches on the surface can be more advantageously suppressed.

Examples of the image display apparatus include wearable devices such as televisions, smart phones, mobile phones, car navigation systems, tablet PCs, portable game machines, electronic papers, indicators, bulletin boards, watches, and smart watches. Examples of the flexible display include an image display device having flexible characteristics, for example, a television, a smartphone, a mobile phone, a car navigation system, a tablet PC, a mobile game machine, an electronic paper, an indicator, a bulletin board, a watch, and a wearable device.

[Example]

Hereinafter, the present invention will be described in more detail by way of Examples. "%" and "part" in an example mean mass % and mass part, unless otherwise indicated.

[Measurement of physical properties of resin]

[Weight Average Molecular Weight]

The weight average molecular weight was measured using GPC. The preparation method and measurement conditions of a measurement sample are as follows.

(1) Sample preparation method

20 mg of resin powder was measured and taken, 10 mL of DMF (10 mmol/L lithium bromide added) was added, and it was completely dissolved. This solution was filtered with a chromatography disk (pore diameter 0.45 mu m) to prepare a sample solution.

(2) Measurement conditions

Device: HLC-8020GPC

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

Eluent: DMF (addition of 10 mmol/L lithium bromide)

Flow rate: 1.0 mL/min

Detector: RI Detector

Column temperature: 40°C

Injection volume: 100 μL

Molecular Weight Standard: Standard Polystyrene

[Production Example: Preparation of polyamideimide resin]

A reaction vessel equipped with a stirrer and a thermometer was replaced with nitrogen, cooled to 10°C, and DMAc as a solvent was placed in the vessel. Furthermore, TFMB, 6FDA, OBBC, and TPC were added by the molar ratio shown to Condition 1 in Table 1, and the solution 1 containing the polyamic acid 1 was prepared.

Next, diisopropylethylamine (DIEA), acetic anhydride, and 4-picoline (4-PC) are added to the polyamic acid solution, and the reaction vessel is heated to 70° C., whereby the polyamideimide resin solution as the reaction solution is (a ₀ ) was obtained. Table 2 shows the molar ratio of each raw material to 1.0000 moles of TFMB.

When the obtained reaction solution was cooled and dropped to 45° C. or less, methanol was added in the molar ratio shown in Condition 1 in Table 3 to 1.0000 mol of TFMB, and polyamideimide resin solution (a1) (density: 910 kg/m 3 , obtained amount of 2,000 kg) was obtained. The viscosity of the polyamide-imide resin solution (a1) was 1 Pa·s, and no precipitation of the polyamide-imide resin was observed in the polyamide-imide resin solution (a1). In addition, the amount of polyamideimide resin contained in the polyamideimide resin solution (a1) is 5 mass% based on the total amount of the polyamideimide resin solution (a1), and the amount of DMAc as a good solvent is 70 mass%, The amount of methanol as a solvent was 21 mass %. In addition, the weight average molecular weight of the polyamideimide resin contained in the polyamideimide resin solution (a1) was 330,000. The polyamideimide resin solution (a1) is also referred to as a solution (a1) below.

Polyamideimide resin solution (a2) (density: 910 kg/m 3 , obtained amount 2 kg) was prepared in the same manner as in Condition 1 except that the molar ratio of each component was changed to the molar ratio shown in Condition 2 in Tables 1 to 3. got it The viscosity of the polyamideimide resin solution (a2) was 5 Pa·s, and precipitation of the polyamideimide resin was not observed in the polyamideimide resin solution (a2). In addition, the amount of polyamideimide resin contained in the polyamideimide resin solution (a2) is 5 mass% based on the total amount of the polyamideimide resin solution (a2), and the amount of DMAc as a good solvent is 70 mass%, The amount of methanol as a solvent was 21 mass %. In addition, the weight average molecular weight of the polyamideimide resin contained in the polyamideimide resin solution (a2) was 600,000. The polyamideimide resin solution (a2) is also referred to as a solution (a2) below.

[Measurement of viscosity]

(1) measurement sample

A part of each of the polyamideimide resin solution (a1) and the polyamideimide resin solution (a2) prepared in the above production example was taken out to be a measurement sample, and the viscosity was determined under the following measurement conditions.

(2) Measurement conditions

Device name: LVDV-II+Pro (manufactured by Brookfield)

Measuring temperature: 10℃

Spindle: CPE-52

Sample volume: 0.55 mL

Rotor rotation speed: 0.3 rpm

[Measurement of particle size of resin powder]

Under the measurement conditions shown below, the volume-based median diameter of the wet solid obtained in the Example and the comparative example was calculated|required by the laser diffraction type scattering method, and the obtained value was made into the particle diameter of resin powder. In addition, the parameter δ representing the uniformity of the particle size was calculated by formula (F) by taking the particle size when the frequency was x% in the obtained particle size distribution as dx.

δ=(d ₉₀ −d ₁₀ )/d ₅₀ Formula (F)

(Measuring conditions)

Device name: Mastersizer 3000 (manufactured by malvern)

Measurement temperature: room temperature

Sample volume: 40-50 mL

Refractive Index: 1.53

Based on the results of particle size measurement, particle size, uniformity, and final quality were evaluated according to the following criteria. Moreover, in each evaluation criterion, (double-circle) is very good, (circle) is good, and x is bad.

(Evaluation criteria for particle size)

(double-circle): particle size of 200 µm or more and less than 500 µm

○: particle size is less than 200 μm, or 500 μm or more and less than 1000 μm

x: a particle size of 1000 µm or more

(Evaluation criteria of uniformity)

◎: parameter δ is 1.0 or less

○: Parameter δ is greater than 1.0 and less than or equal to 5.0

×: parameter δ is greater than 5.0

(final quality)

A: Both particle size and uniformity are ◎

B: One of the particle size and uniformity is ◎, and the other is ○

C: Both particle size and uniformity are ○

D: One of the particle size and uniformity is ○ or ◎, and the other is ×

E: Both particle size and uniformity are ×

In addition, A to C are pass, and D and E are fail.

(Calculation of stirring power)

The stirring power (Z [kW/m3]) was calculated by the formula (D) and obtained.

Z = Np × ρ × (n/60) ³ × d ⁵ /V/1000 Formula (D)

In formula (D), Np represents the number of power, ρ represents the liquid density [kg/m3], n represents the stirring rotation speed [rpm], d represents the blade diameter [m] of the stirring blade, V is the volume of the liquid [m3]. The power number Np was obtained from the correlation between the power number Np and the Reynolds number Re described in the catalog of Shinko Environmental Solutions.

The Reynolds number Re is calculated by the formula (E).

Re = ρ × n/60 × d ² /μ Equation (E)

(in formula (E), μ represents the liquid viscosity [Pa s], ρ represents the liquid density [kg/m 3], n represents the number of stirring rotations [rpm], and d is the blade diameter of the stirring blade [ m]).

(Confirmation of solubility of resin in solvent)

With respect to the resin obtained in Preparation Example, solubility in a solvent was confirmed by the following method.

9.9 g of a solvent was measured and taken in a 30 mL glass screw tube, and a magnetic stirrer was further put and stirred. 0.1 g of resin powder was added there, and it stirred at room temperature (24 degreeC) for 3 hours, and confirmed solubility. As a result, the resin powder was dissolved in DMAc, but not in methanol and ion-exchanged water. Therefore, DMAc is a good solvent, and methanol and ion-exchanged water are poor solvents. In addition, in this Example and a comparative example, the ion-exchange water is simply described as water.

< Example 1 >

While stirring 870 kg of polyamideimide resin solution (a1) at a rotation speed of 125 rpm with a 3-sheet retracting blade (d = 1.2 m), to the solution (a1), a spray nozzle (manufactured by Ikeuchi Corporation, A total of 92 kg of water was continuously added from a full cone nozzle (1/2M JJXP 010S303) at an addition rate (Y) of 0.6 kg/min. At this time, the water sprayed from the spray nozzle would come into contact with the solution (a1). The area (X) of the supply interface region at the time was 0.5 m2, and the addition flow rate (Y/X) was 1.2 ((kg/min)/m2) (full addition) After the addition of 92 kg of water was completed, further 153 kg of water was continuously added from another spray nozzle (manufactured by Ikeuchi Co., Ltd., full cone nozzle (1/2M JJXP 20 S303) at an addition rate of 5 kg/min) (late addition). The area of the interface region was 0.5 m 2 , and the addition flow rate (Y/X) was 10 (kg/min)/m 2. In addition, the weighted average addition rate of the first half addition and the second half addition was 3.35 kg/min, and the weighted average addition flow rate was It was 6.7 (kg/min)/m 2. Moreover, the ratio (supply interface area|region/sub-cross-sectional area) of the supply interface area|region in Example 1 was 0.37.

The precipitated white solid was collected by pressure filtration at 20 to 80 kPa to obtain a wet solid. The wet solid was granular with a particle size of 460 µm, and the parameter δ indicating the uniformity of the particle size was 1.0.

< Example 2 >

While stirring 680 kg of polyamideimide resin solution (a1) at a rotation speed of 114 rpm with a 3-sheet retracting blade (d=1.2 m), to the solution (a1), a spray nozzle (manufactured by Ikeuchi Corporation, A total of 71 kg of water was intermittently added from a full cone nozzle (1/2M JJXP 20 S303) at an addition rate (Y) of 5 kg/min (stirring was continued until the addition of water was completed, and the The ratio of the time during which only stirring was performed was 1: 8. Specifically, the operation of adding water for 30 seconds at an addition rate (Y) of 5 kg/min and stirring for 4 minutes without adding water was repeated. The area (X) of the feed interface region at that time was 0.5 m 2 , and the addition flow rate (Y/X) was 10 (kg/min)/m 2 . The ratio (feed interface area/minor cross-sectional area) to the minor cross-sectional area was 0.37.

The precipitated white solid was collected by pressure filtration at 20 to 80 kPa to obtain a wet solid. The wet solid was granular with a particle size of 310 μm, and the parameter δ was 0.8.

< Example 3 >

While stirring 2,700 g of the polyamideimide resin solution (a1) at a rotational speed of 323 rpm with a 3-sheet retracting blade (d=0.11 m), the solution (a1) was discharged from the dropping nozzle at 1.2 g/min (1.2 × A total of 320 g of water was continuously dripped at an addition rate (Y) of ^{10 -3 kg/min).} The area (X) of the supply interface region at that time was 1.4×10 ^-5 m 2 , and the addition flow rate (Y/X) was 86 (kg/min)/m 2 .

The precipitated white solid was collected by filtration under reduced pressure to obtain a wet solid. The wet solid was granular with a particle size of 630 μm, and the parameter δ was 1.3.

<Example 4>

While stirring 260 g of polyamideimide resin solution (a1) at a rotation speed of 520 rpm with a 3-sheet retracting blade (d=0.11 m), 9.0 g/min (9.0 x A total of 70 g of water was continuously dripped at an addition rate (Y) of ^{10 -3 kg/min).} At that time, the area (X) of the supply interface region was 2.8 × 10 ^-5 m 2 , and the addition flow rate (Y/X) was 321 (kg/min)/m 2 .

The precipitated white solid was collected by filtration under reduced pressure to obtain a wet solid. The wet solid was granular with a particle size of 80 μm, and the parameter δ was 3.1.

<Example 5>

While stirring 260 g of polyamideimide resin solution (a2) at a rotational speed of 520 rpm with a 3-sheet retracting blade (d=0.11 m), 9.0 g/min (9.0×) to the solution (a2) from the dropping nozzle. 10 ^-3 kg/min) of 70 g of water was continuously added dropwise at an addition rate (Y). At that time, the area (X) of the supply interface region was 2.8 × 10 ^-5 m 2 , and the addition flow rate (Y/X) was 321 (kg/min)/m 2 .

The precipitated white solid was collected by filtration under reduced pressure to obtain a wet solid. The wet solid was granular with a particle size of 40 μm, and the parameter δ was 2.0.

< Comparative Example 1 >

While stirring 260 g of polyamideimide resin solution (a1) at a rotation speed of 532 rpm with a 3-sheet retracting blade (d = 0.11 m), 17.0 g/min (17.0 x 17.0 x 75 g of water were continuously added dropwise at an addition rate (Y) of 10 ^{-3 kg/min).} The area (X) of the supply interface region at that time was 2.8×10 ⁻⁵ m 2 , and the addition flow rate (Y/X) was 607 (kg/min)/m 2 .

The precipitated white solid was collected by filtration under reduced pressure to obtain a wet solid. The wet solid was a lump having a particle size of 1000 µm or more.

Tables 4 and 5 show the conditions for adding the poor solvent to the polyamideimide resin solution in Examples and Comparative Examples and the evaluation results of the obtained powder.

As shown in Examples 1 to 5, the polyamide-based resin solution (a) and the poor solvent solution (b) containing at least one poor solvent for the polyamide-based resin were added at a flow rate of 400 or less. It was confirmed that the polyamide-based resin powder obtained by the production method of the present invention including the step of contacting was a powder having a small particle size and a small variation in particle size. On the other hand, as shown in Comparative Example 1, when the addition flow rate exceeded 400, the obtained polyamide-based resin powder had a large particle size and a large particle size variation.

Claims (12)

A polyamide-based resin solution (a) in which a polyamide-based resin is dissolved in a good solvent for the polyamide-based resin and a poor solvent solution (b) containing at least one poor solvent for the polyamide-based resin at least a contacting step of contacting, wherein the area of the supply interface region in the contacting step is X m 2 , and the addition rate of the polyamide-based resin solution (a) or poor solvent solution (b) is Y kg/min. When Equation (A) is:
Addition flow rate ((kg/min)/m2) = Y/X Formula (A)
The addition flow rate calculated by the method for producing a polyamide-based resin powder is 400 or less. The method of claim 1,
The said contacting process is a manufacturing method which is performed by adding a poor solvent solution (b) to a polyamide-type resin solution (a). 3. The method according to claim 1 or 2,
In the contacting step, when the poor solvent solution (b) is added to the polyamide-based resin solution (a), the stirring power of the polyamide-based resin solution (a) is Z kW/m3, and the polyamide-based resin solution is When (a) is added to the poor solvent solution (b), if the stirring power of the poor solvent solution (b) is Z kW/m3, the formula (B):
Ratio R=(Y/X)/Z Formula (B)
The ratio R of the addition flow rate to the stirring power calculated by is 300 or less. 4. The method of claim 3,
It said contacting step, the ratio R is, and each including another first contact step and the second contacting step at least, the ratio of R ₁ in the first contacting step is the liquid is less than the ratio R ₂ of the second contacting step, producing method. 5. The method of claim 4,
_{The manufacturing method whose ratio R<1>} in a 1st contact process is 150 or less. 3. The method according to claim 1 or 2,
The polyamide-based resin solution (a) has a viscosity of 0.5 to 100 Pa·s. 3. The method according to claim 1 or 2,
The polyamide-based resin is selected from the group consisting of polyamide resins and polyamideimide resins. 3. The method according to claim 1 or 2,
In the contacting step, the polyamide-based resin solution (a) or the poor solvent solution (b) is added using at least one selected from the group consisting of a spray, a dripping nozzle, a shower, and a nozzle dispersion plate, manufacturing method. 9. The method of claim 8,
The method of claim 1, wherein the addition is performed using a spray. 3. The method according to claim 1 or 2,
The polyamide-based resin solution (a) further contains at least one poor solvent. 11. The method of claim 10,
_{A polyamide-based resin solution (a 0} ) in which a polyamide-based resin is dissolved in a good solvent for the polyamide-based resin _{, and a poor solvent solution (b 0 )} comprising at least one poor solvent for the polyamide-based resin ) to contact the polyamide-based resin solution (a), further comprising a step of obtaining the polyamide-based resin solution (a). 12. The method of claim 11,
In the step of obtaining the polyamide-based resin solution (a _{), the area of the supply interface region when the polyamide-based resin solution (a 0} ) and the poor solvent solution (b ₀ ) are brought into contact is P m 2 , Assuming that the addition rate of the resin solution (a ₀ ) or the poor solvent solution (b ₀ ) is Q kg/min, the following formula:
Addition flow rate ((kg/min)/m2) = Q/P
The addition flow rate calculated by the method is greater than 400.