JP7352837B2 - Polymer blend films and laminates - Google Patents

Description

The present invention relates to a polymer blend film containing polyamideimide as a main component, a laminate using the polymer blend film, and a method for producing a polymer blend film. More specifically, the present invention relates to a polymer blend film used in various electronic components such as FPC (flexible printed wiring board) and COF (chip on film) films that require heat resistance, and a method for producing the polymer blend film.

Polyamide-imide films generally have excellent heat resistance, strength, insulation, chemical resistance, and processability, and are widely used as electronic and electrical insulating materials. The method for producing polyamide-imide film generally consists of three major steps.
(1) Varnish is cast onto a metal endless belt or resin film as a support and dried until it becomes tack-free.
(2) Peeling off from the support.
(3) Heat-treat the peeled film to remove residual solvent.

Examples of heat treatment methods include the pin tenter method and the clip tenter method, which can suppress wrinkles in the film due to volumetric shrinkage that occurs when the solvent evaporates by gripping both ends of the peeled film (Patent Documents 1 and 2). .

However, the above-mentioned method has a problem in that the stress of volumetric shrinkage during solvent volatilization is concentrated at the edges of the film, so that the film is likely to break, which may reduce productivity. Further, there is also the problem that film waste easily gets mixed in during manufacturing, and appearance defects such as scratches and dents occur during winding.

As a method other than the pin tenter method or clip tenter method, a method has been disclosed in which the desired product is obtained by casting on a metal foil/resin film laminate, heat-treating the laminate, removing residual solvent, and then peeling off the film. (Patent Documents 3 and 4).

Japanese Patent Application Publication No. 09-29852 Patent No. 4428016 Japanese Patent Application Publication No. 2004-322441 Japanese Patent Application Publication No. 2010-201889

However, there is a problem in that the resin layer cast on the metal foil/resin film laminate comes into contact with the metal foil layer when it is rolled up into a roll, resulting in appearance defects such as scratches and dents on the surface of the cast resin layer. Further, the resin film serving as the support and the target resin film may be fused during heat treatment, resulting in poor releasability.

As mentioned above, existing manufacturing methods have problems with production efficiency such as breakage, tearing, and poor peeling of the film, and problems with film quality such as scratches and dents on the film surface. In particular, electronic components are required to be lighter and more compact, and there is a need to reduce the thickness of the film as much as possible. As the thickness of the film becomes thinner, problems such as film breakage and poor peeling become apparent. Furthermore, if the target resin solution is dried without gripping the support film, the support film will warp, and the warp of the target resin film will also increase. If the warpage of the film increases, the volume of the electronic component increases, making it difficult to make it compact.

Therefore, an object of the present invention is to provide a polymer blend film that can be easily peeled off from a resin film without causing scratches or dents on the film surface and has little warpage, and a method for producing the polymer blend film.

The present invention relates to a polymer blend film containing polyamideimide as a main component, and a laminate using the polymer blend film. A polymer blend film is a film made of a composition containing (blending) polyamideimide and a component having a specific structure (hereinafter also referred to as a polymer blend composition). By containing the component having the above-mentioned specific structure, even if the solvent component in the polymer blend film is reduced to 1.5% by mass or less during film formation, it exhibits good releasability from the resin film that is the support. This discovery led to the present invention.

That is, the polymer blend film of the present invention and its manufacturing method consist of the following configuration.

（一般式（Ｉ）中、ｎは１以上の整数であり、ｍは５以上の整数である。）A polymer blend film containing 0.1 to 15 parts by mass of a compound having a structure represented by general formula (I) based on 100 parts by mass of polyamide-imide.

(In general formula (I), n is an integer of 1 or more, and m is an integer of 5 or more.)

（一般式（ＩＩ）中、Ｒ_１およびＲ_２は同じであっても異なっていてもよく、それぞれ独立に、水素、炭素数１～４のアルキル基、又は炭素数１～４のアルコキシ基を示す。）The polyamideimide preferably contains a structure represented by general formula (II) as a structural unit, and preferably has an acid value of 250 eq/10 ⁶ g or less.

(In general formula (II), R ₁ and R ₂ may be the same or different, and each independently represents hydrogen, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. show.)

It is preferable to contain 1 to 30 parts by mass of conductive particles per 100 parts by mass of polyamideimide.

The weight loss rate of the polymer blend film at 150°C to 300°C is preferably 1.5% by mass or less, the glass transition temperature is preferably 280°C or higher, and the thickness is preferably 1 to 50 μm. The warpage is preferably 40 mm or less, and the light transmittance is preferably 50% or more.

A laminate in which a polyimide film is laminated on at least one surface of the polymer blend film. The peel strength of the polymer blend film from the laminate is preferably 0.01 to 1 N/cm.

（一般式（Ｉ）中、ｎは１以上の整数であり、ｍは５以上の整数である。）
（１）支持体である樹脂フィルムの少なくとも片面に、ポリアミドイミド１００質量部に対して、一般式（Ｉ）で表される構造を有する化合物を０．１～１５質量部含有するポリマーブレンド組成物をキャストし積層体を作製する工程
（２）ポリマーブレンド組成物層を支持体の樹脂フィルムから剥離せず積層体の状態でポリマーブレンド組成物層を乾燥する工程
（３）支持体の樹脂フィルムからポリマーブレンド組成物層を剥離し、ポリマーブレンドフィルムを得る工程A polymer blend film having the following steps (1) to (3) and containing 0.1 to 15 parts by mass of a compound having a structure represented by general formula (I) based on 100 parts by mass of polyamideimide. Production method.

(In general formula (I), n is an integer of 1 or more, and m is an integer of 5 or more.)
(1) A polymer blend composition containing 0.1 to 15 parts by mass of a compound having a structure represented by general formula (I) based on 100 parts by mass of polyamideimide on at least one side of a resin film that is a support. (2) Step of drying the polymer blend composition layer in the state of a laminate without peeling the polymer blend composition layer from the resin film of the support (3) From the resin film of the support Step of peeling off the polymer blend composition layer to obtain a polymer blend film

It is preferable that the resin film serving as the support is a polyimide film, is a single layer, and has a thickness of 1 to 500 μm.

The polymer blend film of the present invention contains (blends) a component having a specific structure different from that of the polyamide-imide into the polyamide-imide, thereby reducing the solvent component in the polymer blend film to 1.5% by mass or less during film formation. Even after drying, it can be easily peeled off from the resin film support, which is industrially advantageous. The obtained polymer blend film has high heat resistance and low warpage.

Below, a polymer blend film, a method for producing a polymer blend film, and a laminate using the polymer blend film according to embodiments of the present invention will be described.

<Polyamideimide>
The polyamide-imide in the present invention is not particularly limited as long as it is a resin containing an amide group and an imide group in its structure. Polyamide-imide can be synthesized, for example, by an isocyanate method, an amine method (eg, an acid chloride method, a low-temperature solution polymerization method, a room-temperature solution polymerization method, etc.). It is preferable that the polyamideimide is soluble in an organic solvent. Therefore, from an industrial standpoint, it is preferable to synthesize by the isocyanate method, which allows the solution during polymerization to be coated as is.

In the case of the isocyanate method, polyamideimide can be synthesized by heating and polycondensing an isocyanate component with an acid component such as tricarboxylic anhydride, dicarboxylic acid, or tetracarboxylic anhydride in an organic solvent.

Examples of organic solvents include amide solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, tetramethylurea, and 1,3-dimethyl-2-imidazolidinone; Sulfur solvents such as dimethyl sulfoxide and sulfolane, ketone solvents such as cyclohexanone and methyl ethyl ketone, nitro solvents such as nitrobenzene and nitroethane, ether solvents such as diglyme and tetrahydrofuran, nitrile solvents such as acetonitrile and propionitrile, γ Examples include ester solvents such as -butyllactone and γ-valerolactone, and these can be used alone or in combination.

The copolymerization reaction for producing a polyamide-imide solution (polyamide-imide varnish) is preferably carried out in the above-mentioned solvent at 10° C. to 200° C. for 1 hour to 24 hours. More preferably, the temperature is 100°C or more and 150°C or less for 2 hours or more and 15 hours or less. Further, the reaction may be carried out in the presence of a catalyst for the reaction between the isocyanate component and the active hydrogen compound, such as tertiary amines, alkali metal compounds, alkaline earth metal compounds, and the like. For example, it may be carried out in the presence of triethylenediamine as a tertiary amine.

Although the solid content concentration of the polyamide-imide solution (polyamide-imide varnish) can be selected from a wide range, it is preferably 5% by mass or more and 40% by mass or less, since this is particularly excellent in processability. More preferably, the content is particularly preferably 8% by mass or more and 20% by mass or less.

As the acid component of polyamideimide, it is preferable to use tricarboxylic acid or tetracarboxylic acid, and it is more preferable to use tricarboxylic acid and tetracarboxylic acid together. It is also preferable to use monoanhydrides, dianhydrides, or esters of tricarboxylic or tetracarboxylic acids. Tricarboxylic acids include 1,2,4-naphthalene tricarboxylic acid, diphenyl ether-3,3',4'-tricarboxylic acid, diphenylsulfone-3,3',4'-tricarboxylic acid or trimellitic acid, and one of these. Examples include anhydrides and esters. Further, hydrogenated products of the above-mentioned monomers can be mentioned, such as hexahydrotrimellitic acid, and monoanhydrides or esters of hexahydrotrimellitic acid. Examples of tetracarboxylic acids include benzophenone-3,3',4,4'-tetracarboxylic acid, biphenyl-3,3',4,4'-tetracarboxylic acid, diphenyl ether-3,3',4,4'- Tetracarboxylic acid, ethylene glycol bis(trimelitate), bisphenol bis(trimelitate), 3,3',4,4'-diphenylsulfone tetracarboxylic acid, naphthalene-2,3,6,7-tetracarboxylic acid, naphthalene-1 , 2,4,5-tetracarboxylic acid, naphthalene-1,4,5,8-tetracarboxylic acid, or pyromellitic acid, and their monoanhydrides, dianhydrides, or esterified products. Further, hydrogenated products of the above monomers such as hexahydropyromellitic acid and monoanhydride, dianhydride or esterified product of hexahydropyromellitic acid can be mentioned. Also, dicarboxylic acids may be used. Examples of dicarboxylic acids include isophthalic acid, terephthalic acid, biphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid, and diphenylsulfone dicarboxylic acid, and also hydrogenated products of the above monomers such as cyclohexane dicarboxylic acid. These acid components can be used alone or as a mixture of two or more.

As the tricarboxylic acid, trimellitic anhydride or hexahydrotrimellitic anhydride is preferred. In addition, examples of the tetracarboxylic acid include benzophenone-3,3',4,4'-tetracarboxylic dianhydride, biphenyl-3,3',4,4'-tetracarboxylic dianhydride, diphenyl ether-3, 3',4,4'-tetracarboxylic dianhydride or cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride is preferable, and these may be used alone or in a mixture of two or more. Can be used as a component. More preferably, trimellitic anhydride is used alone or trimellitic anhydride, benzophenone-3,3',4,4'-tetracarboxylic dianhydride and biphenyl-3,3',4 , 4'-tetracarboxylic dianhydride. When used in combination, the amount of trimellitic acid anhydride is preferably 60 to 90 mol%, more preferably 70 to 85 mol%, when the total acid component is 100 mol%. Furthermore, the amount of benzophenone-3,3',4,4'-tetracarboxylic dianhydride is preferably 8 to 30 mol%, more preferably 10 to 15 mol%. Furthermore, the amount of biphenyl-3,3',4,4'-tetracarboxylic dianhydride is preferably 2 to 10 mol%, more preferably 5 to 8 mol%.

As the isocyanate component of polyamide-imide, amine components are illustrated below, and isocyanate components corresponding to the following amine components can be used. The amine component includes p-phenylenediamine, m-phenylenediamine, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, , 4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 3,3'-diaminobenzanilide, 4,4'-diaminobenzanilide, 4,4'-diaminobenzophenone, 3,3'-diaminobenzo Phenone, 3,4'-diaminobenzophenone, 2,6-tolylenediamine, 2,4-tolylenediamine, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenylsulfide, 4,4 '-Diaminodiphenylpropane, 3,3'-diaminodiphenylpropane, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, p-xylene diamine, m-xylene diamine, 1,4-naphthalenediamine, 1, 5-naphthalenediamine, 2,6-naphthalenediamine, 2,7-naphthalenediamine, 2,2'-bis(4-aminophenyl)propane, 1,3-bis(3-aminophenoxy)benzene, 1,3- Bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, bis[4-(4-aminophenoxy) phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]propane, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4' -bis(3-aminophenoxy)biphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4-methyl-1,3-phenylenediamine, 3,3'-diethyl-4,4'-diaminobiphenyl , 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-diethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3' -Diethoxy-4,4'-diaminobiphenyl, trans-1,4-diaminocyclohexane, cis-1,4-diaminocyclohexane, 1,4-diaminocyclohexane (trans/cis mixture), 1,3-diaminocyclohexane, dicyclo Hexylmethane-4,4'-diamine (trans form, cis form, trans/cis mixture), isophorone diamine, 1,4-cyclohexane bis(methylamine), 2,5-bis(aminomethyl)bicyclo[2.2 .1] heptane, 2,6-bis(aminomethyl)bicyclo[2.2.1]heptane, 3,8-bis(aminomethyl)tricyclo[5.2.1.0]decane, 1,3 -Diaminoadamantane, 4,4'-methylenebis(2-methylcyclohexylamine), 4,4'-methylenebis(2-ethylcyclohexylamine), 4,4'-methylenebis(2,6-dimethylcyclohexylamine), 4 , 4'-methylenebis(2,6-diethylcyclohexylamine), 2,2-bis(4-aminocyclohexyl)propane, 2,2-bis(4-aminocyclohexyl)hexafluoropropane, 1,3-propanediamine , 1,4-tetramethylenediamine, 1,5-pentamethylenediamine, 1,6-hexamethylenediamine, 1,7-heptamethylenediamine, 1,8-octamethylenediamine, 1,9-nonamethylenediamine, etc. can be used. These can be used alone or in a mixture of two or more. Further, diisocyanates corresponding to these can be used alone or in a mixture of two or more.

As the amine component (isocyanate component), preferably 3,3'-dimethyl-4,4'-diaminobiphenyl, dicyclohexylmethane-4,4'-diamine (trans form, cis form, trans/cis mixture), 4, 4'-diaminodiphenyl ether, m-phenylenediamine, p-phenylenediamine, or 4-methyl-1,3-phenylenediamine and their corresponding diisocyanate components. These can be used alone or in a mixture of two or more. Among these, 3,3'-dimethyl-4,4'-diaminobiphenyl and the corresponding diisocyanate component (o-toridine diisocyanate) are preferred.

The mixing ratio of the acid component and the amine component is preferably such that the molar ratio of the acid component to the total amine component is 0.95 to 1.05.

It is preferable that the polyamideimide contains a structure represented by general formula (II) as a structural unit. By including the structure represented by general formula (II), sufficient heat resistance can be imparted to polyamideimide.

In general formula (II), R ₁ and R ₂ may be the same or different and each independently represents hydrogen, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. . Examples of the alkyl group having 1 to 4 carbon atoms include methyl group, ethyl group, n-propyl group and isopropyl group. Examples of the alkoxy group having 1 to 4 carbon atoms include methoxy group, ethoxy group, n-propoxy group and isopropoxy group. Both R ₁ and R ₂ are preferably hydrogen or a methyl group, more preferably a methyl group. The position of R ₁ is preferably the 2-position with respect to the imide group, and the position of R ₂ is preferably the 3'-position.

The structure represented by general formula (II) preferably accounts for 100 mol% or more, more preferably 120 mol% or more, still more preferably 150 mol% It is mol% or more. If the amount is too small, the heat resistance will decrease, and the heat resistance may be insufficient for use as an electronic material. Moreover, it is preferably 190 mol% or less, more preferably 180 mol% or less. If the amount is too large, solvent solubility may deteriorate, a uniform film may not be obtained, and film formability may deteriorate.

The polyamideimide preferably has a molecular weight corresponding to a logarithmic viscosity of 0.3 to 2.8 dl/g at 30°C in N-methyl-2-pyrrolidone (polymer concentration 0.5 g/dl), and more preferably Preferably, it has a molecular weight corresponding to 0.5 to 2.5 dl/g. If the logarithmic viscosity is less than 0.3 dl/g, the mechanical properties may be insufficient when molded into a film or the like, and if it exceeds 2.8 dl/g, the solution viscosity will be high. Molding may be difficult. A suitable solution viscosity of polyamideimide is in the range of 20 to 1000 dPa·s at 25°C. If the solution viscosity is outside the above range, coating properties may deteriorate.

The acid value of polyamideimide is preferably 250 eq/10 ⁶ g or less. More preferably, it is 200 eq/10 ⁶ g or less, and still more preferably 160 eq/10 ⁶ g or less. If the acid value is too high, the adhesion to the resin film of the support may become high and the releasability may deteriorate. The lower limit is not particularly limited, but 50 eq/10 ⁶ g is sufficient, and 80 eq/10 ⁶ g or more is also acceptable.

<Compound having a structure represented by general formula (I)>
The polymer blend film of the present invention contains 0.1 to 15 parts by weight of a compound having a structure represented by general formula (I) (hereinafter also referred to as general formula (I) compound) per 100 parts by weight of polyamide-imide. Contains part. Preferably it is 0.5 parts by mass or more, more preferably 1 part by mass or more, and even more preferably 2 parts by mass or more. If the amount is too small, the polymer blend film may not be able to be peeled off from the resin film that is the support. Moreover, it is preferably 12 parts by mass or less, more preferably 10 parts by mass or less, and even more preferably 8 parts by mass or less. If the amount is too large, transparency (light transmittance) may decrease.

一般式（Ｉ）において、ｎは１以上の整数であり、好ましくは２以上の整数であり、より好ましくは３以上の整数である。また、１５以下の整数であることが好ましく、より好ましくは１２以下の整数である。ｍは５以上の整数であり、好ましくは８以上の整数であり、さらに好ましくは１０以上の整数である。また１００００以下の整数であることが好ましく、より好ましくは８０００以下の整数である。ｎ、ｍが上記範囲を外れると、ポリマーブレンドフィルムの透明性が悪化することがある。ｎ、ｍとも上記範囲内とすることでポリマーブレンドフィルムの優れた透明性、反り性および剥離性を発現することができる。By having the following polyoxyethylene alkyl ether structure, the compound of general formula (I) can be easily peeled off from the resin film while maintaining the heat resistance, transparency, and warpage of the polymer blend film.

In general formula (I), n is an integer of 1 or more, preferably an integer of 2 or more, and more preferably an integer of 3 or more. Further, it is preferably an integer of 15 or less, more preferably an integer of 12 or less. m is an integer of 5 or more, preferably an integer of 8 or more, and more preferably an integer of 10 or more. Further, it is preferably an integer of 10,000 or less, more preferably 8,000 or less. When n and m are out of the above range, the transparency of the polymer blend film may deteriorate. By setting both n and m within the above ranges, the polymer blend film can exhibit excellent transparency, warp resistance, and peelability.

The molecular weight of the compound of general formula (I) is preferably 1,000 or more, more preferably 1,500 or more. If the molecular weight is too low, it may easily volatilize during high temperature treatment, making it difficult to achieve the original effect during peeling. Further, it is preferably 100,000 or less, more preferably 50,000 or less. If it is too high, the compatibility with polyamideimide may deteriorate and transparency may deteriorate.

Commercially available products of the compound of general formula (I) include Disperbyk 2013 and Disperbyk 2025 of the Disperbyk (registered trademark) series manufactured by BYK Chemie Japan Co., Ltd.

If necessary, other additives may be added to the polymer blend film for the purpose of improving various properties of the film, such as mechanical properties, electrical properties, slipperiness, and flame retardancy, to the extent that the effects of the present invention are not impaired. The resin, organic compound, conductive particles, and inorganic compound (inorganic particles) may be mixed or reacted. Further, the polymer blend composition is preferably a solution of the organic solvent.

As the conductive particles, for example, carbon black (acetylene black, channel black, furnace black, etc.), graphite (graphite), aniline black, titanium black, etc. can be used. Black is preferred.

As the inorganic particles, for example, silica, alumina, titanium oxide, magnesium oxide, etc. can be used. Inorganic particles subjected to hydrophobic treatment are preferred because they have improved affinity with polyamideimide and improved dispersibility.

When containing (blending) conductive particles, it is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 1 part by mass, based on 100 parts by mass of polyamideimide. The amount is more preferably 2 parts by mass or more, particularly preferably 5 parts by mass or more. Further, the amount is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, even more preferably 15 parts by mass or less, even more preferably 12 parts by mass or less, and particularly preferably 10 parts by mass or less. be. By setting it within the above range, the surface resistance value can be reduced while suppressing embrittlement of the polymer blend film. The surface resistance value of the polymer blend film when containing conductive particles is preferably 10 ⁷ Ω/□ or less, more preferably 10 ⁶ Ω/□ or less, and even more preferably 10 ⁴ Ω/□ or less. It is. Although the lower limit is not particularly limited, there is no problem industrially as long as it is 10 ² Ω/□ or more. Although the polymer blend film of the present invention itself has high transparency (light transmittance), if it contains conductive particles, the transparency (light transmittance) may decrease.

When containing (blending) inorganic particles, it is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more, and even more preferably 1 part by mass or more, based on 100 parts by mass of polyamideimide. and particularly preferably 2 parts by mass or more. If the amount is too small, the effect of the inorganic particles may not be obtained. Moreover, it is preferably 15 parts by mass or less, more preferably 12 parts by mass or less, still more preferably 10 parts by mass or less, and particularly preferably 8 parts by mass or less. If the amount is too high, the transparency (light transmittance) may decrease or the film may become brittle.

The method of blending the conductive particles and inorganic particles is not particularly limited. It is sufficient that the polyamide-imide solution after blending is uniformly mixed. Homogeneous refers to a state in which there is no macroscopic phase separation to the extent that visible light scattering does not occur. When macroscopic phase separation occurs, for example, when formed into a film, a significant decrease in transparency and strength occurs.

The polymer blend film is a film made of a polymer blend composition containing the polyamideimide and the compound of general formula (I). The polymer blend composition can contain the other resins, organic compounds, conductive particles, and inorganic compounds (inorganic particles). The content of polyamideimide in the polymer blend composition is preferably 70% by mass or more, more preferably 75% by mass or more, and even more preferably 80% by mass or more. If it is too small, heat resistance, transparency, and warp resistance may deteriorate. Moreover, it is preferably 98% by mass or less, more preferably 95% by mass or less, and still more preferably 90% by mole or less. If it is too large, the relative content of the compound of general formula (I) may decrease, and the releasability from the resin film may decrease.

The polymer blend film preferably has a weight loss rate of 1.5% by mass or less at 150°C to 300°C. More preferably it is 1.2% by mass or less, and still more preferably 1.0% by mass or less. If the weight reduction rate is less than or equal to the above-mentioned weight reduction rate, no problem will occur when incorporated into a device as an FPC or COF. The lower limit is not particularly limited, but 0.1% by mass or more is sufficient, and 0.2% by mass or more is also acceptable. Here, the weight loss rate refers to the amount of weight loss measured between 150°C and 300°C when a sample of the polymer blend film is heated from room temperature to 400°C in a nitrogen atmosphere.

The heat resistance of a polymer blend film can be expressed by its glass transition temperature. The glass transition temperature of the polymer blend film of the present invention is preferably 280°C or higher, more preferably 300°C or higher, and still more preferably 320°C or higher. If the temperature is above the above-mentioned temperature, there is no risk of deformation due to heat during the reflow process.

The thickness of the polymer blend film can be selected from a wide range, but the thickness after bone drying (residual solvent: 1.5% by mass or less) is preferably about 1 μm or more and about 50 μm or less, more preferably about 10 μm or more and about 40 μm or less. , more preferably 20 μm or more and 30 μm or less. If the thickness is less than 1 μm, mechanical properties such as film strength and handling properties will be poor, while if the thickness exceeds 50 μm, processability (drying properties, coatability), etc. may deteriorate. Further, surface treatment may be performed as necessary. For example, surface treatments such as hydrolysis, corona discharge, low-temperature plasma, physical roughening, and adhesive coating can be applied.

The warpage of the polymer blend film is preferably 40 mm or less, more preferably 30 mm or less, and still more preferably 25 mm or less. If it exceeds the above range, it may be difficult to use it for FPC or COF applications. Further, the lower limit is not particularly limited, but 10 mm is industrially sufficient.

The light transmittance of the polymer blend film is preferably 50% or more, more preferably 52% or more, and still more preferably 55% or more. If it is less than the above range, the polymer blend film will have poor transparency. Further, the upper limit is not particularly limited, but 70% or less may be acceptable industrially.

<Method for producing polymer blend film>
In the present invention, the polymer blend film is preferably produced by a method in which the polymer blend composition is cast (coated) on at least one side of a resin film that is a support, a laminate is produced, and the laminate is peeled off after drying. . The polymer blend composition may be cast on one side (polymer blend film layer/resin film) or both sides (polymer blend film layer/resin film/polymer blend film layer) of the resin film. The casting method is not particularly limited, and conventionally well-known methods can be applied. For example, the viscosity of the polymer blend composition as a coating liquid can be adjusted using a roll coater, knife coater, doctor, blade coater, gravure coater, die coater, reverse coater, etc., and then directly applied to the resin film. Specifically, it is preferable to include the following steps (1) to (3). By having the steps (1) to (3) below, even if the residual solvent in the polymer blend film is dried to 1.5% by mass or less, it can be easily peeled off from the resin film that is the support with a good yield. , a polymer blend film can be obtained.

<Step (1)>
Step (1) is a polymer containing 0.1 to 15 parts by mass of a compound having a structure represented by general formula (I) based on 100 parts by mass of polyamideimide on at least one side of a resin film that is a support. This is a step of producing a laminate by casting the blend composition.

<Resin film>
The resin film used as a support in the present invention is not particularly limited, but is preferably a polyimide film. Polyimide film is a heat-resistant film made of a polymer having an imide group in its structure, including so-called polyimide, such as polyamideimide, polybenzimidazole, polyimide ester, polyetherimide, polysiloxane imide, etc. Bye. Polyimide films can be used without problems as long as they can function as a support for casting polymer blend compositions, and are films with excellent solvent resistance to the solvents of polymer blend compositions, heat resistance that can withstand heat treatment processes, and peelability. Good to have. Further, the polyimide used for the polyimide film preferably has a composition different from that of polyamideimide, and is preferably a polyimide without amide bonds. Further, the resin film may be a single layer or a multilayer, but is preferably a single layer.

A polyimide film can be produced by solution polymerization of a known diamine and acid anhydride. Examples of the diamine include 4,4'-diaminodiphenyl ether, 2'-methoxy-4,4'-diaminobenzanilide, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-amino phenoxy)benzene, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'- Diaminobiphenyl, 4,4'-diaminobenzanilide, 2,2-bis-[4-(3-aminophenoxy)phenyl]propane, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[4-( 3-aminophenoxy)phenyl] sulfone, bis[4-(4-aminophenoxy)]biphenyl, bis[4-(3-aminophenoxy)biphenyl, bis[1-(4-aminophenoxy)]biphenyl, bis[1 -(3-aminophenoxy)]biphenyl, bis[4-(4-aminophenoxy)phenyl]methane, bis[4-(3-aminophenoxy)phenyl]methane, bis[4-(4-aminophenoxy)phenyl] Ether, bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-aminophenoxy)]benzophenone, bis[4-(3-aminophenoxy)]benzophenone, bis[4,4'-( 4-aminophenoxy)]benzanilide, bis[4,4'-(3-aminophenoxy)]benzanilide, 9,9-bis[4-(4-aminophenoxy)phenyl]fluorene, 9,9-bis[4- (3-aminophenoxy)phenyl]fluorene, 2,2-bis-[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis-[4-(3-aminophenoxy)phenyl]hexafluoro Propane, 4,4'-methylenedi-o-toluidine, 4,4'-methylenedi-2,6-xylidine, 4,4'-methylene-2,6-diethylaniline, 4,4'-diaminodiphenylpropane, 3 , 3'-diaminodiphenylpropane, 4,4'-diaminodiphenylethane, 3,3'-diaminodiphenylethane, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide , 3,3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenyl ether, 3,3-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether , benzidine, 3,3'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxybenzidine, 4,4''-diamino-p-terphenyl, 3,3 ''-diamino-p-terphenyl, m-phenylenediamine, p-phenylenediamine, 2,6-diaminopyridine, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy) ) Benzene, 4,4'-[1,4-phenylenebis(1-methylethylidene)]bisaniline, 4,4'-[1,3-phenylenebis(1-methylethylidene)]bisaniline, bis(p-amino cyclohexyl)methane, bis(p-β-amino-t-butylphenyl)ether, bis(p-β-methyl-δ-aminopentyl)benzene, p-bis(2-methyl-4-aminopentyl)benzene, p -Bis(1,1-dimethyl-5-aminopentyl)benzene, 1,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,4-bis(β-amino-t-butyl)toluene, 2,4- Diaminotoluene, m-xylene-2,5-diamine, p-xylene-2,5-diamine, m-xylylenediamine, p-xylylenediamine, 2,6-diaminopyridine, 2,5-diaminopyridine, 2 , 5-diamino-1,3,4-oxadiazole, piperazine, etc. can be used.

Examples of acid anhydrides include pyromellitic anhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, and 3,3',4,4'-diphenylsulfone tetracarboxylic dianhydride. 4,4'-oxydiphthalic anhydride, 2,2',3,3'-, 2,3,3',4'- or 3,3',4,4'-benzophenonetetracarboxylic dianhydride 2,3',3,4'-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 2,3',3,4'-diphenyl ether tetra Carboxylic dianhydride, bis(2,3-dicarboxyphenyl)ether dianhydride, 3,3'', 4,4''-, 2,3,3'',4''- or 3,2 '',3,3''-p-terphenyltetracarboxylic dianhydride, 2,2-bis(2,3- or 3,4-dicarboxyphenyl)-propane dianhydride, bis(2,3 - or 3,4-dicarboxyphenyl) methane dianhydride, bis(2,3- or 3,4-dicarboxyphenyl) sulfone dianhydride, 1,1-bis(2,3- or 3,4- dicarboxyphenyl)ethane dianhydride, 1,2,7,8-, 1,2,6,7- or 1,2,9,10-phenanthrene-tetracarboxylic dianhydride, 2,3,6, 7-anthracenetetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)tetrafluoropropane dianhydride, 2,3,5,6-cyclohexane dianhydride, 2,3,6, 7-naphthalenetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 4,8-dimethyl-1, 2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 2,6- or 2,7-dichloronaphthalene-1,4,5,8-tetra Carboxylic dianhydride, 2,3,6,7-(or 1,4,5,8-)tetrachloronaphthalene-1,4,5,8-(or 2,3,6,7-)tetracarvone Acid dianhydride, 2,3,8,9-, 3,4,9,10-, 4,5,10,11- or 5,6,11,12-perylene-tetracarboxylic dianhydride, cyclo Pentane-1,2,3,4-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride , thiophene-2,3,4,5-tetracarboxylic dianhydride, 4,4'-bis(2,3-dicarboxyphenoxy)diphenylmethane dianhydride, and the like can be used.

Only one type of diamine and acid anhydride may be used, or two or more types thereof may be used in combination. Note that the polyimide is not limited to that obtained from the above-mentioned diamine and acid anhydride.

Only one type of diamine and acid anhydride may be used, or two or more types thereof may be used in combination. Note that the polyimide is not limited to that obtained from the above-mentioned diamine and acid anhydride.

Further, the reaction between the diamine and the acid anhydride is preferably carried out in an organic solvent, and the organic solvent is not particularly limited, but specifically, for example, dimethyl sulfoxide, N,N-dimethylformamide, etc. , N,N-dimethylacetamide, N-methyl-2-pyrrolidone, hexamethylphosphoformamide, phenol, cresol, γ-butyrolactone, etc., and these can be used alone or in combination. Further, the amount of such an organic solvent to be used is not particularly limited, but it may be used by adjusting the amount so that the concentration of the polyamic acid obtained by the polymerization reaction is about 5 to 30% by mass. preferable.

In the reaction using the organic solvent, it is preferable that the molar ratio of the diamine and the acid anhydride to the total diamine is 0.95 to 1.05.

The reaction between the diamine and the acid anhydride is preferably carried out at a temperature of 0° C. to 60° C. for 1 hour to 24 hours. If such temperature conditions are below the lower limit (0°C), the reaction rate tends to be slow and the increase in molecular weight does not proceed. On the other hand, if it exceeds the upper limit (60°C), imidization progresses and the reaction solution tends to gel more easily. By reacting under such temperature conditions, a resin solution of polyamic acid, which is a precursor of polyimide resin, can be efficiently obtained.

Polyamic acid synthesized from diamine and acid anhydride is used as a solution. The method of forming an imide group by ring closure of polyamic acid is not particularly limited as long as it does not impair the physical properties of the polyimide film, but examples include a thermal imidization method by heating, a chemical imidization method using a dehydration condensation agent and an imidization catalyst, etc. A method of imidization using a method can be used.

<Example of method for manufacturing resin film>
As the resin film used in the present invention, a method for producing a polyimide film will be illustrated below, but the present invention is not limited thereto. As a method for producing a polyimide film, for example, the polyamic acid solution is cast onto a support, first dried to a tack-free state, and then peeled from the support to prevent the film from shrinking and wrinkles. There is a method of heat-treating the polyimide film in a fixed state to obtain a polyimide film. As a support for producing a resin film, for example, a resin film such as a polyimide film or a PET film, or a thin metal such as aluminum or copper is used, but from the viewpoint of handling property and cost, a PET film is preferable.

The thickness of the resin film is preferably 1 to 500 μm, more preferably 10 to 200 μm, and still more preferably 20 to 100 μm. If it is less than 1 μm, it may not be able to withstand the weight of the cast polymer blend composition, causing the film to curve and the solution to flow out. Further, when used as a support, warpage may become large. On the other hand, if it exceeds 500 μm, the film stiffness may be high and handling properties may be poor.

A commercially available product can be used as the polyimide film. For example, Kapton (registered trademark) series (Dupont Toray Co., Ltd.), Apical (registered trademark) series (Kaneka Corporation), Upilex (registered trademark) series (Ube Industries, Ltd.), LN series (SKC Kolon PI Corporation) However, the scope of application of the present invention is not limited thereto.

The amount of casting may be, for example, such that the desired thickness of the polymer blend film after drying is obtained.

<Step (2)>
Step (2) is a step of drying the polymer blend composition layer in the form of a laminate without peeling the polymer blend composition layer from the resin film of the support. By drying the laminate as it is, the manufacturing process can be simplified and the polymer blend film can be manufactured with a high yield.

There are no particular limitations on drying conditions, but drying may be performed at a temperature near the boiling point of the solvent or at a temperature above the boiling point of the solvent. Although it depends on the resin composition of polyamideimide, the temperature is preferably 100°C or more and 450°C or less, more preferably 150°C or more and 300°C or less. For example, the solvent may be removed by heating at 100° C. for 10 minutes, then at 200° C. for 10 minutes, and then at 300° C. for 1 hour under nitrogen. Within the above range, the peelability from the resin film, the heat resistance, surface smoothness, and transparency of the polymer blend film are good, there are few deterioration reactions, the polymer blend film does not become brittle, and can be dried in a short time. Good productivity.

Drying may be performed under an inert gas atmosphere or under reduced pressure. Examples of the inert gas include nitrogen, carbon dioxide, helium, and argon, but it is preferable to use nitrogen, which is easily available. In order to suppress coloring of the film and obtain a colorless and transparent film, it is desirable to lower the oxygen concentration to 0.5% or less, more preferably 0.1% or less. In addition, when carrying out under reduced pressure, it is preferable to carry out under a pressure of about 10 ^-5 Pa to 10 ³ Pa, preferably about 10 ^-1 Pa to 200 Pa.

There are no particular limitations on the method for both initial drying and heat treatment, but continuous processing can be performed using conventionally known methods such as a roll support method or a floating method. Further, continuous heat treatment in a heating furnace such as a tenter type is also possible.

The drying is preferably carried out until the solvent component in the polymer blend film is 1.5% by mass or less, more preferably 1.2% by mass or less, and still more preferably 1.0% by mass or less. If the solvent component is too large, the polymer blend film may warp significantly. The polymer blend film of the present invention can be easily peeled off from the resin film even when dried to a residual solvent content of 1.5% by mass or less. If the solvent component is too large, the polymer blend film may warp significantly. The lower limit is not particularly limited, but 0.1% by mass or more is sufficient, and 0.2% by mass or more is also acceptable. If the solvent component is too small, it may not be possible to peel it off easily from the resin film.

<Step (3)>
Step (3) is a step of peeling off the polymer blend composition layer from the resin film of the support to obtain a polymer blend film. The peel strength when peeling the polymer blend film layer from the resin film of the support is preferably 0.07 N/cm or more, more preferably 0.08 N/cm or more, and even more preferably 0.1 N/cm. cm or more. If it is less than the above range, the peel strength is too weak and it may peel off from the resin film during drying, causing wrinkles on the film and contamination in the drying oven. Moreover, it is preferably 1 N/cm or less, more preferably 0.5 N/cm or less, and still more preferably 0.3 N/cm or less. If it exceeds the above range, the peel strength will be too strong and the polymer blend film may be damaged during peeling.

The polymer blend film of the present invention can be easily peeled off from a resin film and has excellent heat resistance, transparency, and low warpage. Further, by the production method of the present invention, a single polymer blend film can be easily obtained. There is no limitation on the method of peeling, and it can be easily peeled off using conventionally known methods. For example, it can be manufactured by winding up the resin film and the polymer blend film into separate rolls while peeling the polymer blend film after continuous heat treatment. With conventional methods, it has been difficult to efficiently produce a polymer blend film that has excellent heat resistance and low warpage, is easy to peel, and has a good yield. However, this became possible for the first time with the disclosure of the present invention.

After the polymer blend film of the present invention is peeled from the laminate (polymer blend film/resin film), it can be further laminated with another resin film to produce a laminate different from the laminate. The resin film that can be used in this case may be the same as or different from the resin film described above. Moreover, it is preferable that the peel strength is also within the above range.

Hereinafter, the present invention will be explained in more detail with reference to Examples. Note that the present invention is not particularly limited to the examples. The method for evaluating characteristic values in each example is as follows.

<Glass transition temperature>
Using a polymer blend film as a sample, the glass transition temperature was measured using a TMA (thermo-mechanical analyzer/manufactured by Seiko Instruments Inc. (trade name: EXSTAR TMA/SS 6000)) under the following conditions using the tensile loading method. was measured. The inflection point of the obtained curve was defined as the glass transition temperature (Tg), tangents were drawn to each of the lower temperature region (glass region) and higher temperature region (rubber region) than Tg, and the temperature was calculated as the intersection of these tangents. It is judged that the higher the glass transition temperature, the higher the heat resistance.
Load: 5g
Sample size: 4mm (width) x 20mm (length)
Heating rate: 10℃/min Atmosphere: Nitrogen

<Logarithmic viscosity>
In accordance with the method for determining the viscosity of a diluted polymer solution described in JIS-K7367-1:2002 (ISO-1628-1:1998), the logarithmic viscosity of polyamide-imide was determined using an Ubbelohde viscometer under the following conditions. was measured.
Measurement temperature: 30℃
Solvent: N-methyl-2-pyrrolidone (25ml)
Resin amount: 0.125g

<Acid value>
0.4 g of polyamideimide was dissolved in 20 ml of N-methyl-2-pyrrolidone, and the acid value was measured by titration with a 0.1N sodium methoxide/methanol solution. Phenolphthalein was used as an indicator. The measured value was converted into equivalent weight per 10 ⁶ g of sample, and the unit was eq/10 ⁶ g.

<Warp>
The polymer blend film was cut into the following sample sizes. A film that had been conditioned for 24 hours at 25° C. and 65% RH was placed on a horizontal glass stand in a downwardly convex state, and the distance that the four corners of the film were floating from the stand was measured. The distances of the four points were totaled and evaluated as warpage.
Sample size: 20cm x 20cm

<Transparency>
Transparency was determined by light transmittance. The polymer blend film was measured using a spectrophotometer (trade name: V650/manufactured by JASCO Corporation). In order to measure the parallel light transmittance, an integrating sphere unit that receives diffused light was not used, and measurements were made under standard conditions. Measurement range: 300 to 800 nm, and the value was read at 600 nm.

<Releasability>
A laminate of resin film/polymer blend film was used as a sample and peeled using Tensilon under the following conditions, and the stress at the time of peeling was defined as peel strength (N/cm).
Tensile speed: 20mm/min Peeling angle: 180°
Sample size: 15mm (length) x 10mm (width)

<Residual solvent amount>
Using TGA (product name: DTA-60/manufactured by Shimadzu Corporation), the polymer blend film was heated from room temperature to 400°C in a nitrogen atmosphere, the weight loss rate was calculated from the following formula, and this was calculated as the polymer blend film. It was defined as the amount of residual solvent in the film.
Heating rate: 5℃/min Sample weight: 30mg
Weight loss rate (%): (weight loss from 150℃ to 300℃/initial weight) x 100

<Surface resistance>
Using a resistivity meter (trade name: Loresta GP/manufactured by Mitsubishi Chemical Analytic Tech), the surface resistance of the polymer blend film was measured under measurement conditions in accordance with JIS K 7194 (1994). A resistance value of 10 ⁸ Ω/□ or more was the measurement limit, and the film in this case was used as an insulating film.

Synthesis examples of polyamide-imide and polyamide-imide solutions are shown below.
(Synthesis Example 1: Synthesis of polyamideimide A (resin A))
18.14 g (80 mol%) of trimellitic dianhydride, 4.75 g (12.5 mol%) of 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 3,3',4, 2.60 (7.5 mol%) of 4'-biphenyltetracarboxylic dianhydride, 31.19 (100 mol%) of o-tolidine diisocyanate, and 262.33 g of N-methyl-2-pyrrolidone were added, and the mixture was heated under a nitrogen atmosphere. The mixture was reacted at 100°C for 5 hours. After the reaction, the mixture was diluted with N-methyl-2-pyrrolidone so that the polymer concentration was 10% by mass. The obtained polyamide-imide had a logarithmic viscosity of 2.01 dl/g, an acid value of 110 eq/10 ⁶ g, and a solution viscosity of 400 dPa·s.

(Synthesis Example 2: Synthesis of polyamideimide B (resin B))
Add 22.67 g (100 mol%) of trimellitic anhydride, 24.95 g (80 mol%) of o-toridine diisocyanate, 4.11 (20 mol%) of toluene diisocyanate, and 165.38 g of N-methyl-2-pyrrolidone. The mixture was reacted at 100° C. for 5 hours under a nitrogen atmosphere. After the reaction, the mixture was diluted with N-methyl-2-pyrrolidone so that the polymer concentration was 15% by weight. The obtained polyamideimide had a logarithmic viscosity of 1.51 dl/g, an acid value of 160 eq/10 ⁶ g, and a solution viscosity of 400 dPa·s.

(Synthesis Example 3: Synthesis of polyamideimide C (resin C))
Trimellitic anhydride 15.37g (80mol%), pyromellitic anhydride 4.36g (20mol%), o-tolidine diisocyanate 21.14g (80mol%), diphenylmethane diisocyanate 5.01g (20mol%) ), 210.11 g of N-methyl-2-pyrrolidone were added, and the mixture was reacted at 100° C. for 5 hours under a nitrogen atmosphere. After the reaction, the mixture was diluted with N-methyl-2-pyrrolidone so that the polymer concentration was 10% by mass. The obtained polyamideimide had a logarithmic viscosity of 1.68 dl/g, an acid value of 150 eq/10 ⁶ g, and a solution viscosity of 580 dPa·s.

(Example 1)
Add 0.02 g of Disperbyk 2013 as a compound of general formula (I) to 20 g of polyamide-imide A solution (resin component: 2 g), and blend it at room temperature by hand stirring with a glass rod until it becomes homogeneous to obtain Polymer Blend Composition 1. Obtained. Polymer blend composition 1 was cast (coated) on a polyimide film Kapton 100EN (manufactured by DuPont-Toray) as a resin film as a support so that the thickness after drying (heat treatment) was 25 μm. Then, it was dried at 100° C. for 10 minutes to obtain a laminate. Thereafter, the laminate was fixed only on two sides facing the iron frame, and dried (heat treated) at 200°C for 30 minutes and at 300°C for 15 minutes. The polymer blend film was peeled from the laminate after drying (heat treatment), and the obtained physical properties are shown in Table 1. All of the obtained polymer blend films were free of wrinkles and had flatness.

(Examples 2 to 10, Comparative Examples 1 to 3)
A polymer blend film was obtained in the same manner as in Example 1, except that the polyamide-imide solution, the compound of general formula (I), and the resin film were changed as shown in Table 1. The physical properties are also shown in Table 1. In addition, Comparative Examples 2 and 3 were strongly adhered to the polyimide film and could not be peeled off. Furthermore, all of the obtained polymer blend films were free of wrinkles and had flatness.

(Example 11)
Examples The general formula (I) compound and resin film were used, except that a solution containing 0.20 g of ECP600JD (manufactured by Lion Corporation) as conductive particles was used for 20 g of polyamide-imide A solution (resin component: 2 g). A polymer blend film was obtained using the same method as in 1. The physical properties are also shown in Table 1.

(Example 12)
The same method as in Example 11 was used except that a solution containing 20 g of polyamide-imide A solution (resin component: 2 g) and 0.20 g of VULCAN-XC72 (manufactured by Cabot Corporation) as conductive particles was used. A blended film was obtained. The physical properties are also shown in Table 1.

(Reference example 1)
Add 0.02 g of Disperbyk 2013 as a compound of general formula (I) to 20 g of polyamide-imide A solution (resin component: 2 g), and blend it at room temperature by hand stirring with a glass rod until it becomes homogeneous to obtain Polymer Blend Composition 1. Obtained. Polymer blend composition 1 was cast (coated) on a polyimide film Kapton 100EN (manufactured by DuPont-Toray) as a resin film as a support so that the thickness after drying (heat treatment) was 25 μm. Then, it was dried at 100° C. for 10 minutes to obtain a laminate. The polymer blend film was peeled off from the laminate, the single polymer blend film was fixed on only two sides facing the iron frame, and dried (heat treated) at 200° C. for 30 minutes and at 300° C. for 15 minutes. The obtained physical properties are also shown in Table 1. The polymer blend film had wrinkles all over it due to shrinkage during heat treatment, and flatness could not be obtained, making it impossible to evaluate transparency, warpage, and glass transition temperature.

The compounds of general formula (I) used in Table 1 are as follows.
Disperbyk2013: Manufactured by BYK Chemie Japan Co., Ltd. (compound containing a polyoxyethylene alkyl ether component having an alkyl chain with 3 or more carbon atoms and a polypropylene glycol component)
Disperbyk2025: Manufactured by BYK Chemie Japan Co., Ltd. (compound containing a polyoxyethylene alkyl ether component and a polymethacrylate component)
Further, compounds different from the compounds of general formula (I) used in Table 1 are as follows.
Disperbyk192: Manufactured by BYK Chemie Japan Co., Ltd. (compound containing no polyoxyethylene alkyl ether and containing an unsaturated fatty acid ester component having 13 or more carbon atoms)

The resin films used in Table 1 are as follows.
Kapton (registered trademark) 100EN: polyimide film manufactured by DuPont-Toray Co., Ltd., thickness 25 μm
Kapton (registered trademark) 50EN: polyimide film manufactured by DuPont-Toray Co., Ltd., thickness 12.5 μm
Apical (registered trademark) 25NPI: Polyimide film manufactured by Kaneka Corporation, thickness 25 μm
LN: Polyimide film manufactured by SKC Kolon PI Co., Ltd., thickness 25 μm
Upilex (registered trademark) -25S: Polyimide film manufactured by Ube Industries, Ltd., thickness 25 μm

Claims (17)

Contains 0.1 to 15 parts by mass of a compound having a structure represented by general formula (I) per 100 parts by mass of polyamideimide, and the polyamideimide has a structure represented by general formula (II) as a structural unit. A polymer blend film containing 100 mol % or more and 190 mol % or less of the structure represented by general formula (II) when the total constituent components of the polyamide-imide are 200 mol %.

(In general formula (I), n is an integer of 1 or more, and m is an integer of 5 or more.)

(In general formula (II), R1 and R2 may be the same or different and each independently represents hydrogen, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. ) The polymer blend film according to claim 1 , containing 0.1 to 30 parts by mass of conductive particles based on 100 parts by mass of polyamideimide. The polymer blend film according to claim 1 or 2, characterized in that the weight loss rate at 150° C. to 300° C. is 1.5% by mass or less. The polymer blend film according to any one of claims 1 to 3 , having a glass transition temperature of 280°C or higher. 5. The polymer blend film according to claim 1 , wherein the polyamide-imide has an acid value of 250 eq/10 ⁶ g or less. The polymer blend film according to any one of claims 1 to 5 , wherein the polymer blend film has a thickness of 1 to 50 μm. The polymer blend film according to any one of claims 1 to 6 , wherein the polymer blend film has a warpage of 40 mm or less. The polymer blend film according to any one of claims 1 to 7 , wherein the polymer blend film has a light transmittance of 50% or more. A laminate comprising a polyimide film laminated on at least one surface of the polymer blend film according to any one of claims 1 to 8 . The laminate according to claim 9 , wherein the polymer blend film has a peel strength of 0.01 to 1 N/cm from the laminate. It has the following steps (1) to (3), contains 0.1 to 15 parts by mass of a compound having a structure represented by general formula (I) to 100 parts by mass of polyamideimide, and contains a structure represented by general formula (II) as a structural unit, and when the total constituent components of the polyamideimide are 200 mol%, the structure represented by general formula (II) is 100 mol% or more, 190 mol% % or less .

(In general formula (I), n is an integer of 1 or more, and m is an integer of 5 or more.)

(In general formula (II), R1 and R2 may be the same or different and each independently represents hydrogen, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. )
(1) A polymer blend composition containing 0.1 to 15 parts by mass of a compound having a structure represented by general formula (I) based on 100 parts by mass of polyamideimide on at least one side of a resin film that is a support. (2) Step of drying the polymer blend composition layer in the state of a laminate without peeling the polymer blend composition layer from the resin film of the support (3) From the resin film of the support Step of peeling off the polymer blend composition layer to obtain a polymer blend film The method for producing a polymer blend film according to claim 11 , wherein the resin film that is the support is a polyimide film. The method for producing a polymer blend film according to claim 11 or 12, wherein the resin film is a single layer. The method for producing a polymer blend film according to any one of claims 10 to 13, wherein the polymer blend film has a thickness of 1 to 50 μm. The method for producing a polymer blend film according to any one of claims 10 to 14, wherein the resin film has a thickness of 1 to 500 μm. The method for producing a polymer blend film according to any one of claims 10 to 15, wherein the polymer blend film has a light transmittance of 50% or more. The method for producing a polymer blend film according to any one of claims 10 to 16, wherein the polymer blend film has a warpage of 40 mm or less.