JP7600633B2 - Resin composition, film, multilayer film, and method for producing film - Google Patents

Description

The present invention relates to a resin composition, a film using the resin composition, a multilayer film, and a method for producing a film.
In particular, the present invention relates to a film that is preferably used as a protective film or substrate for a transparent conductive film.

Transparent conductive films are used in film sensors of touch panels, electronic paper, dye-sensitized solar cells, touch sensors, etc. A transparent conductive film 10 is known that is composed of an electrode layer (transparent conductive film) 11, a substrate 12, an adhesive layer 13, and a protective film 14, for example, as shown in FIG.
Specifically, Patent Document 1 describes a transparent conductive film laminate having an adhesive layer, a film substrate, and a transparent conductive film in this order on a protective film, in which a polycarbonate-based resin is used as the protective film.

JP 2018-152187 A

On the other hand, from the viewpoint of improving the heat resistance of the film, a polyarylate resin may be blended with an aromatic polycarbonate resin to produce a film. It has been found that when a film is produced using a roll from a resin composition containing such an aromatic polycarbonate resin and a polyarylate resin, stains may occur on the roll.
The present invention aims to solve such problems, and to provide a resin composition that is less likely to cause roll stains when attempting to produce a film using a roll, as well as a film, a multilayer film, and a method for producing a film that use the resin composition.

（式（Ｐ１）および式（Ｐ２）中、Ｒ^xは、それぞれ独立に、炭素数３～３０の直鎖または分岐のアルキル基を示す。）
＜５＞前記ホスフェート化合物の金属塩が、式（Ｐ１－１）で表される化合物および式（Ｐ２－１）で表される化合物の少なくとも１種を含む、＜１＞または＜２＞に記載の樹脂組成物。
式（Ｐ１－１） 式（Ｐ２－１）

＜６＞前記ポリアリレート樹脂の重量平均分子量が３０，０００～５５，０００である、＜１＞～＜５＞のいずれか１つに記載の樹脂組成物。
＜７＞前記樹脂組成物の示差走査熱量測定により測定したガラス転移温度が１５５℃以上である、＜１＞～＜６＞のいずれか１つに記載の樹脂組成物。
＜８＞前記芳香族ポリカーボネート樹脂の重量平均分子量が２０，０００～３８，０００である、＜１＞～＜７＞のいずれか１つに記載の樹脂組成物。
＜９＞＜１＞～＜８＞のいずれか１つに記載の樹脂組成物から形成されたフィルム。
＜１０＞厚みが２５～５００μｍである、＜９＞に記載のフィルム。
＜１１＞＜９＞または＜１０＞に記載のフィルムを含む多層フィルム。
＜１２＞前記フィルムの片側または両側に、ハードコート層、アンチブロッキング層、粘着層、接着層およびインデックスマッチング層の少なくともいずれか１つの層を有する、＜１１＞に記載の多層フィルム。
＜１３＞＜１＞～＜８＞のいずれか１つに記載の樹脂組成物を押出し、ロールを搬送させて成形することを含む、フィルムの製造方法。
In view of the above problems, the present inventors have conducted research and found that the above problems can be solved by blending a metal salt of a phosphate compound with an alloy of an aromatic polycarbonate resin and a polyarylate resin.
Specifically, the above problems were solved by the following means.
<1> A resin composition comprising 20 to 80 parts by mass of an aromatic polycarbonate resin, 80 to 20 parts by mass of a polyarylate resin, and a metal salt of a phosphate compound.
<2> The resin composition according to <1>, further comprising 0.01 to 0.15 parts by mass of a metal salt of a phosphate compound per 100 parts by mass of the total of the aromatic polycarbonate resin and the polyarylate resin.
<3> The resin composition according to <1> or <2>, wherein the metal salt of the phosphate compound includes a zinc salt of the phosphate compound.
<4> The resin composition according to <1> or <2>, wherein the metal salt of the phosphate compound includes at least one of a compound represented by formula (P1) and a compound represented by formula (P2).
Formula (P1) Formula (P2)

(In formula (P1) and formula (P2), R ^x each independently represents a linear or branched alkyl group having 3 to 30 carbon atoms.)
<5> The resin composition according to <1> or <2>, wherein the metal salt of the phosphate compound includes at least one of a compound represented by formula (P1-1) and a compound represented by formula (P2-1).
Formula (P1-1) Formula ( P2-1 )

<6> The resin composition according to any one of <1> to <5>, wherein the polyarylate resin has a weight average molecular weight of 30,000 to 55,000.
<7> The resin composition according to any one of <1> to <6>, wherein the resin composition has a glass transition temperature of 155° C. or higher as measured by differential scanning calorimetry.
<8> The resin composition according to any one of <1> to <7>, wherein the aromatic polycarbonate resin has a weight average molecular weight of 20,000 to 38,000.
<9> A film formed from the resin composition according to any one of <1> to <8>.
<10> The film according to <9>, having a thickness of 25 to 500 μm.
<11> A multilayer film comprising the film according to <9> or <10>.
<12> The multilayer film according to <11>, having at least one layer selected from the group consisting of a hard coat layer, an antiblocking layer, an adhesive layer, an adhesion layer, and an index matching layer on one or both sides of the film.
<13> A method for producing a film, comprising extruding the resin composition according to any one of <1> to <8> and transporting the extrudate through a roll to form the film.

The present invention makes it possible to provide a resin composition that is less likely to cause roll stains when attempting to manufacture a film using a roll, as well as a film, a multilayer film, and a method for manufacturing a film that uses the resin composition.

FIG. 1 is a schematic cross-sectional view showing an example of a layer structure of a transparent conductive film.

Hereinafter, an embodiment of the present invention (hereinafter, simply referred to as the present embodiment) will be described in detail. Note that the present embodiment is an example for explaining the present invention, and the present invention is not limited to the present embodiment.
In this specification, the word "to" is used to mean that the numerical values before and after it are included as the lower limit and upper limit.
In this specification, various physical properties and characteristic values are those at 23° C. unless otherwise specified.
In the description of groups (atomic groups) in this specification, the notation that does not indicate whether it is substituted or unsubstituted includes both groups (atomic groups) that have no substituents and groups (atomic groups) that have substituents. For example, "alkyl group" includes not only alkyl groups that have no substituents (unsubstituted alkyl groups), but also alkyl groups that have substituents (substituted alkyl groups). In this specification, the notation that does not indicate whether it is substituted or unsubstituted is preferably unsubstituted.
The term "film" as used herein refers to a generally flat molded body having a small thickness relative to its length and width, and is intended to include a sheet. The term "film" as used herein may be either a single layer or a multilayer.
In this specification, "parts by mass" indicates the relative amount of a component, and "% by mass" indicates the absolute amount of a component.
In cases where the standards shown in this specification differ depending on the year and the measurement method, etc., the standards shall be those in effect at the time of filing, unless otherwise stated.

The resin composition of the present embodiment contains 20 to 80 parts by mass of an aromatic polycarbonate resin, 80 to 20 parts by mass of a polyarylate resin, and a metal salt of a phosphate compound. By blending a metal salt of a phosphate compound with such an alloy of an aromatic polycarbonate resin and a polyarylate resin, the film can be effectively prevented from being inhibited even when the film is formed using a roll. Furthermore, a film having a high total light transmittance and low haze can be obtained. Furthermore, a film having excellent heat resistance can be obtained.
The reason why the contamination of the roll can be suppressed is presumed to be as follows.
When aromatic polycarbonate resin is rolled into a film, the roll is hardly stained. However, it has been found that when a resin composition containing a polyarylate resin and an aromatic polycarbonate resin is formed into a film using a roll, roll staining may occur. The present inventors speculated that the roll staining is due to ester exchange between polyarylate resins, and tried to use various ester exchange inhibitors. As a result, it was speculated that the occurrence of roll staining could be suppressed by using a resin composition in which a metal salt of a phosphate compound is blended with an alloy of a polyarylate resin and an aromatic polycarbonate resin.

<Aromatic polycarbonate resin>
The resin composition of the present embodiment contains an aromatic polycarbonate resin. By using an aromatic polycarbonate resin, a film having excellent transparency can be obtained.
The aromatic polycarbonate resin is not particularly limited in type, etc., as long as it contains a -[O-R-OCO]- structural unit (R contains at least an aromatic group and may further contain an aliphatic group, and has a linear or branched structure) containing a carbonate bond in the molecular main chain, and various aromatic polycarbonate resins can be used.

In the present embodiment, the aromatic polycarbonate resin is preferably a bisphenol-type polycarbonate resin. The bisphenol-type polycarbonate resin means that preferably 80 mol % or more, more preferably 90 mol % or more of the structural units constituting the aromatic polycarbonate resin are carbonate structural units derived from bisphenol (preferably bisphenol A) and/or its derivatives.
The bisphenol type polycarbonate resin is preferably a bisphenol A type polycarbonate resin.

The weight average molecular weight of the aromatic polycarbonate resin is preferably 20,000 or more, more preferably 22,000 or more. By making it equal to or more than the lower limit, the moldability of the film tends to be improved. In addition, the upper limit of the weight average molecular weight of the aromatic polycarbonate resin is preferably 38,000 or less, more preferably 35,000 or less, even more preferably 30,000 or less, and even more preferably 28,000 or less. By making it equal to or less than the upper limit, the increase in haze of the film can be effectively suppressed.
The weight average molecular weight of the aromatic polycarbonate resin is measured according to the description in the Examples section described later.
When the composition contains two or more types of aromatic polycarbonate resins, the weight average molecular weight is the weight average molecular weight of the mixture of aromatic polycarbonate resins (the same applies to other physical properties below, and also to other resin components).

The glass transition temperature (Tg) of the aromatic polycarbonate resin is preferably 125°C or higher, more preferably 130°C or higher, and even more preferably 135°C or higher. By making it equal to or higher than the lower limit, shrinkage during heating can be suppressed. In addition, the glass transition temperature (Tg) of the aromatic polycarbonate resin is not particularly specified, but is preferably 160°C or lower, more preferably 155°C or lower, even more preferably 150°C or lower, and even more preferably 145°C or lower. By making it equal to or lower than the upper limit, an increase in the haze of the film can be effectively suppressed.
The glass transition temperature (Tg) of the aromatic polycarbonate resin is measured according to the description in the Examples section described later.

For further details about the aromatic polycarbonate resin, the descriptions in paragraphs 0011 to 0020 of JP 2012-144604 A and the descriptions in paragraphs 0014 to 0035 of JP 2019-002023 A can be referred to without departing from the spirit of this embodiment, and the contents of these are incorporated herein.

<Polyarylate resin>
The resin composition of the present embodiment contains a polyarylate resin. By using the polyarylate resin, a film having excellent heat resistance can be obtained.
The polyarylate resin used in the present embodiment is preferably an aromatic polyester composed of structural units derived from an aromatic dicarboxylic acid and structural units derived from a bisphenol.
Examples of aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, benzophenone dicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 3,3'-diphenyldicarboxylic acid, and 4,4'-diphenylether dicarboxylic acid, and terephthalic acid and/or isophthalic acid are preferred.
Examples of bisphenols include 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane, 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl methane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, and the like. Of these, 2,2-bis(4-hydroxyphenyl)propane (bisphenol A) is preferred. These compounds may be used alone or in combination of two or more.
The polyarylate resin may contain other structural units within a range that does not depart from the spirit of this embodiment (for example, a range of 5 mass % or less of all structural units).

The method for producing the polyarylate resin is not particularly limited, and polyarylate resins obtained by known methods can be used. Polyarylate resins obtained by interfacial polymerization and melt polymerization methods can be preferably used.

The weight average molecular weight of the polyarylate resin is preferably 30,000 or more, more preferably 35,000 or more, and even more preferably 38,000 or more. By setting it to the lower limit or more, the formability of the film tends to improve. In addition, the weight average molecular weight of the polyarylate resin is preferably 55,000 or less, more preferably 50,000 or less, even more preferably 46,000 or less, and even more preferably 43,000 or less. By setting the upper limit of the weight average molecular weight of the polyarylate resin to 55,000 or less, an increase in the haze of the film can be effectively suppressed.

The glass transition temperature (Tg) of the polyarylate resin is preferably 180° C. or higher, more preferably 185° C. or higher, and even more preferably 190° C. or higher. By setting it to the lower limit or higher, shrinkage during heating can be suppressed. The upper limit of the glass transition temperature (Tg) of the polyarylate resin is not particularly specified, but is preferably 220° C. or lower, more preferably 215° C. or lower, even more preferably 210° C. or lower, even more preferably 205° C. or lower, and even more preferably 200° C. or lower. By setting it to the upper limit or lower, an increase in the haze of the film can be effectively suppressed.
The glass transition temperature (Tg) of the polyarylate resin is measured according to the description in the Examples section described later.

<Blend ratio of aromatic polycarbonate resin and polyarylate resin>
The resin composition of the present embodiment contains 20 to 80 parts by mass of aromatic polycarbonate resin and 80 to 20 parts by mass of polyarylate resin, preferably contains 30 to 70 parts by mass of aromatic polycarbonate resin and 70 to 30 parts by mass of polyarylate resin, and more preferably contains 40 to 60 parts by mass of aromatic polycarbonate resin and 60 to 40 parts by mass of polyarylate resin. The blend ratio of aromatic polycarbonate resin and polyarylate resin can be appropriately adjusted depending on the application. By making the content of aromatic polycarbonate resin larger than the content of polyarylate resin, the fluidity increases, so that foreign matter can be removed by a filter. By making the content of polyarylate resin larger than the content of aromatic polycarbonate resin, shrinkage during heating can be suppressed.
In this embodiment, it is particularly preferable that the above range is satisfied when the total amount of the aromatic polycarbonate resin and the polyarylate resin is taken as 100 parts by mass.

The total amount of the aromatic polycarbonate resin and the polyarylate resin in the resin composition of this embodiment is preferably 90 mass % or more, more preferably 95 mass % or more, and even more preferably 99 mass % or more in the resin composition.
The aromatic polycarbonate resin and the polyarylate resin may each be contained alone or in combination of two or more. When two or more types are contained, the total amount is preferably within the above range.

<Metal Salts of Phosphate Compounds>
The resin composition of the present embodiment contains a metal salt of a phosphate compound. By using the metal salt of a phosphate compound, it is possible to effectively suppress roll contamination even when an alloy of an aromatic polycarbonate resin and a polyarylate resin is formed into a film.
The metal constituting the metal salt of the phosphate compound is exemplified by sodium and zinc, and zinc is preferred. That is, the resin composition of the present embodiment preferably contains a zinc salt of a phosphate compound. When the zinc salt of a phosphate compound is used, the effect of the present invention tends to be more effectively exhibited.

In this embodiment, the metal salt of the phosphate compound preferably contains at least one of a compound represented by formula (P1) and a compound represented by formula (P2).
Formula (P1) Formula (P2)

(In formula (P1) and formula (P2), each R ^x independently represents a linear or branched alkyl group having 3 to 30 carbon atoms.)
The number of carbon atoms in R ^x is preferably 8 or more, more preferably 13 or more, and even more preferably 15 or more, and is further preferably 25 or less, even more preferably 20 or less, and most preferably 18.
^Rx is a straight-chain or branched alkyl group, preferably a straight-chain alkyl group.

In this embodiment, it is more preferable that the metal salt of the phosphate compound contains at least one of the compounds represented by formula (P1-1) and (P2-1). In this embodiment, a mixture of the compounds represented by formula (P1-1) and (P2-1) is more preferable.
Formula (P1-1) Formula ( P2-1 )

In the resin composition of this embodiment, the content of the metal salt of the phosphate compound per 100 parts by mass of the aromatic polycarbonate resin and the polyarylate resin is preferably 0.01 parts by mass or more, more preferably 0.02 parts by mass or more, and even more preferably 0.03 parts by mass or more. By making it equal to or more than the lower limit, the occurrence of roll stains can be effectively suppressed. The content of the metal salt of the phosphate compound per 100 parts by mass of the aromatic polycarbonate resin and the polyarylate resin is preferably 0.15 parts by mass or less, more preferably 0.10 parts by mass or less, even more preferably 0.08 parts by mass or less, and even more preferably 0.07 parts by mass or less. By making it equal to or less than the upper limit, the occurrence of roll stains can be effectively suppressed.

The resin composition of this embodiment may contain a phosphate compound that is not substituted with a metal salt, provided that the effect of this embodiment is not significantly deviated from the present embodiment. However, it is preferable that the resin composition of this embodiment is substantially free of a phosphate compound that is not substituted with a metal salt. By "substantially free," it is meant that the content of the phosphate compound that is not substituted with a metal salt is 10% by mass or less of the content of the metal salt of the phosphate compound contained in the resin composition of this embodiment, preferably 5% by mass or less, more preferably 1% by mass or less, and even more preferably 0.1% by mass or less. By adopting such a configuration, the effect of suppressing the dirt on the roll tends to be more effectively exerted.

<Release Agent>
The resin composition of the present embodiment preferably contains a release agent. By containing a release agent, a film having excellent releasability can be obtained.
The release agent may be at least one compound selected from the group consisting of aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, and polysiloxane-based silicone oils, and is preferably an ester of aliphatic carboxylic acids and alcohols.
Specific examples of esters of aliphatic carboxylic acids and alcohols include beeswax (a mixture containing myricyl palmitate as a main component), stearyl stearate, behenyl behenate, stearyl behenate, glycerin monopalmitate, glycerin monostearate, glycerin distearate, glycerin tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, and pentaerythritol tetrastearate.
In addition, as the release agent, the release agents described in paragraph 0032 of JP-A-2017-226848 and paragraph 0056 of JP-A-2018-199745 can be used, the contents of which are incorporated herein by reference.

When the resin composition contains a release agent, the content thereof is preferably 0.001 part by mass or more, more preferably 0.005 part by mass or more, and preferably 2 parts by mass or less, more preferably 1 part by mass or less, and even more preferably 0.5 parts by mass or less, per 100 parts by mass of the total of the aromatic polycarbonate resin and the polyarylate resin.
The release agent may be used alone or in combination of two or more. When two or more types are used, the total amount is preferably within the above range.

<Other Ingredients>
In addition to the above components, the resin composition of the present embodiment may contain other components within the scope of the present invention. Specifically, the resin composition may contain antioxidants, heat stabilizers, flame retardants, flame retardant assistants, ultraviolet absorbers, colorants, antistatic agents, fluorescent brighteners, antifogging agents, flow improvers, plasticizers, dispersants, antibacterial agents, antiblocking agents, impact improvers, sliding improvers, hue improvers, acid trapping agents, etc. These components may be used alone or in combination of two or more.
The resin composition of the present embodiment is adjusted so that the total of the aromatic polycarbonate resin, the polyarylate resin, the metal salt of a phosphate compound, and the release agent and other components that are blended as necessary, is 100 mass %.
The resin composition of this embodiment may contain a phosphorus-based antioxidant, but may not contain one. It is preferable that the resin composition of this embodiment is substantially free of a phosphorus-based antioxidant. "Substantially free" means that the content of the phosphorus-based antioxidant is 10% by mass or less of the content of the phosphorus-based antioxidant contained in the resin composition of this embodiment, preferably 5% by mass or less, more preferably 1% by mass or less, and even more preferably 0.1% by mass or less. By adopting such a configuration, the effect of suppressing the dirt on the roll tends to be more effectively exerted.

<Physical Properties of Resin Composition>
The resin composition of the present embodiment is preferably excellent in heat resistance. Specifically, the glass transition temperature of the resin composition measured by differential scanning calorimetry is preferably 155°C or higher, more preferably 156°C or higher, even more preferably 157°C or higher, even more preferably 158°C or higher, even more preferably 159°C or higher, and even more preferably 160°C or higher. The upper limit of the glass transition temperature is not particularly specified, but is preferably 210°C or lower, more preferably 200°C or lower, even more preferably 190°C or lower, even more preferably 180°C or lower, and even more preferably 170°C or lower. By setting it to the upper limit or lower, the formability of the film tends to be further improved.
The glass transition temperature is measured as described in the Examples section below.

The resin composition of the present embodiment preferably has excellent transparency.
Specifically, the resin composition of the present embodiment has a total light transmittance of preferably 85.0% or more, more preferably 88.0% or more, and even more preferably 90.0% or more when molded into a film having a thickness of 200 μm. The upper limit of the total light transmittance is ideally 100%, but practically 98% or less.
Furthermore, the resin composition of the present embodiment preferably has a haze of 1.0% or less when molded into a film having a thickness of 200 μm, more preferably 0.8% or less, even more preferably 0.5% or less, even more preferably 0.4% or less, and even more preferably 0.2% or less. The lower limit is ideally 0%, but practically 0.01% or more.
The total light transmittance and haze are measured according to the method described in the examples below.

<Film>
The film of the present embodiment is formed from the resin composition of the present embodiment.
The film of this embodiment can be used as a monolayer film. When the film of this embodiment is a monolayer film, its thickness is preferably 25 μm or more, more preferably 30 μm or more, even more preferably 35 μm or more, even more preferably 40 μm or more, and even more preferably 50 μm or more. By making it equal to or greater than the lower limit, there is a tendency that breakage during film formation can be suppressed. In addition, the thickness of the monolayer film is preferably 500 μm or less, more preferably 400 μm or less, even more preferably 300 μm or less, even more preferably 250 μm or less, and even more preferably 200 μm or less. By making it equal to or less than the upper limit, there is a tendency that bending resistance is further improved.

The film of the present embodiment can be used as a multilayer film including the film of the present embodiment (single layer film). As the layer included in the multilayer film, in addition to the film of the present embodiment, known layers can be used.
The film of this embodiment is used as a multilayer film having at least one of a hard coat layer, an antiblocking layer, an adhesive layer, an adhesion layer and an index matching layer on one side or both sides of the film.The film of this embodiment is also preferably used as a transparent conductive film having a protective layer, an adhesive layer, a substrate and an electrode layer in this order, and at least one of the substrate and the protective layer (preferably at least the protective layer) is the film of this embodiment.
The transparent conductive film is also preferably used as a transparent conductive film for use in film sensors of touch panels, electronic paper, dye-sensitized solar cells, touch sensors, and the like.
For details of the multilayer film, the hard coat layer described in paragraphs 0101 to 0108 of International Publication No. 2018/062328, the transparent conductive layer (electrode layer) in paragraphs 0109 to 0112, the adhesive layer described in paragraphs 0125 to 0126, the conductive layer described in paragraphs 0077 to 0082 of JP-A-2020-122124, the index matching (IM) layer, hard coat layer, and anti-blocking hard coat layer described in paragraphs 0083 to 0085, the conductive layer described in paragraphs 0102 to 0105 of JP-A-2018-058233, and the description of the application of the transparent conductive film described in paragraphs 0106 and 0107 can be referred to, and the contents of these are incorporated herein.

When the film of the present embodiment is a multilayer film, its thickness is preferably 25 μm or more, more preferably 35 μm or more, even more preferably 40 μm or more, even more preferably 45 μm or more, and even more preferably 50 μm or more. By making it equal to or greater than the lower limit, breakage of the film during transportation can be effectively suppressed. In addition, the thickness of the multilayer film is preferably 500 μm or less, more preferably 400 μm or less, even more preferably 300 μm or less, even more preferably 250 μm or less, and even more preferably 200 μm or less. By making it equal to or less than the upper limit, cracks during bending can be effectively suppressed.
The film of the present embodiment is also preferably used for applications other than those mentioned above.

The film of this embodiment is manufactured using the resin composition of this embodiment according to a known film manufacturing method. Preferably, the film of this embodiment is manufactured by a method including extruding the resin composition of this embodiment and conveying it through a roll to form it.

As described above, the film of this embodiment may be a single layer film or a multilayer film composed of multiple thermoplastic resin layers. A known method can also be used for manufacturing the multilayer film. For example, during melt extrusion using a T-die, the multilayer film can be formed by laminating the layers inside the die and forming them into a film, or by forming them into a film and then laminating them.

The present invention will be described in more detail below with reference to examples. The materials, amounts, ratios, processing contents, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.
If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be made using other instruments with equivalent performance.

1. Raw Material <Aromatic Polycarbonate Resin (A)>
A1: H-7000F, bisphenol A polycarbonate resin, manufactured by Mitsubishi Engineering Plastics Corporation, Iupilon (registered trademark), weight average molecular weight 24,900, glass transition temperature: 141°C
A2: S-3000F, bisphenol A polycarbonate resin, manufactured by Mitsubishi Engineering Plastics Corporation, Iupilon (registered trademark), weight average molecular weight 41,300, glass transition temperature 148°C
<Polyarylate resin (B)>
B1: U polymer, polyarylate resin, manufactured by Unitika Ltd., product name: U-powder L type, carboxylic acid component: terephthalic acid/isophthalic acid = 50/50 mol%, bisphenol component: bisphenol A = 100 mol%, weight average molecular weight 40,800, glass transition temperature 195°C

<Metal Salt of Phosphate Compound (C)>
C1: A mixture of the following compounds, with a molar ratio of left:right=2:1. JP-518Zn, manufactured by Johoku Chemical Co., Ltd.

<Phosphate Compound (D)>
D1: AX-71, manufactured by ADEKA, ester exchange inhibitor

<Antioxidant (E)>
E1: PEP-36, manufactured by ADEKA Corporation, phosphite-based antioxidant <Release agent (F)>
F1: S-100A glycerin monostearate (Rikemal S-100A, manufactured by Riken Vitamin Co., Ltd.)

2. Examples 1 to 3, Comparative Examples 1 to 3, Reference Example 1
<Production of resin pellets>
Each component was blended in a tumbler to obtain the composition shown in Table 1 or Table 2 below (the contents are shown in parts by mass in each table), and the blend was fed into the base of a twin-screw extruder (TEX30α, manufactured by Japan Steel Works, Ltd.) and melt-kneaded at a cylinder temperature of 280°C to produce pellets for the Examples, Comparative Examples, and Reference Examples.

<Film Production>
The pellets obtained above were extruded in a molten state using a T-die melt extruder consisting of a vented twin-screw extruder (manufactured by Japan Steel Works, Ltd., "TEX30α") with a barrel diameter of 32 mm and a screw L/D of 31.5 at a discharge rate of 10 kg/h and a screw rotation speed of 166 rpm, and the width of the first roll and the second roll was set to 1 mm, and the pellets were cooled and solidified to produce a film. The cylinder temperature was 280°C, and the die head temperature was 300°C. A film with a thickness of 200 μm was obtained.

<Method for measuring weight average molecular weight>
The weight average molecular weight (Mw) of the aromatic polycarbonate resin, the polyarylate resin, and the resin composition was measured by gel permeation chromatography as follows.
The gel permeation chromatography apparatus used was an LC-20AD system (manufactured by Shimadzu Corporation), and an LF-804 (manufactured by Shodex Corporation) was connected as the column. The column temperature was 40° C. The detector used was an RID-10A (manufactured by Shimadzu Corporation) RI detector. Chloroform was used as the eluent, and a calibration curve was created using standard polystyrene (manufactured by Tosoh Corporation).
If the above-mentioned gel permeation chromatography apparatus, column, and detector are difficult to obtain, measurement can be performed using other apparatus having equivalent performance.

<Measurement of Glass Transition Temperature (Tg)>
The glass transition temperature (Tg) of the aromatic polycarbonate resin, the polyarylate resin, and the resin composition was measured by carrying out two cycles of heating and cooling according to the measurement conditions of differential scanning calorimetry (DSC) described below, and the glass transition temperature at the time of heating in the second cycle was measured.
The intersection of the straight line extending the low-temperature side baseline to the high-temperature side and the tangent line of the inflection point was taken as the starting glass transition temperature, the intersection of the straight line extending the high-temperature side baseline to the low-temperature side and the tangent line of the inflection point was taken as the ending glass transition temperature, and the midpoint between the starting glass transition temperature and the ending glass transition temperature was taken as the glass transition temperature (Tg). The measurement conditions for the aromatic polycarbonate resin and the composition were as follows: measurement start temperature: 30°C, heating rate: 10°C/min, final temperature: 200°C, and temperature drop rate: 20°C/min. The measurement conditions for the aromatic polyarylate resin (B) were as follows: measurement start temperature: 30°C, heating rate: 10°C/min, final temperature: 250°C, and temperature drop rate: 20°C/min.
The measurement device used was a differential scanning calorimeter (DSC, Hitachi High-Tech Science Corporation, "DSC7020").

<Roll soiling>
The degree of dirt on the roll after consuming 5 kg of raw material for film production was visually confirmed. The evaluation was carried out by five experts and judged by majority vote.
A: No dirt can be seen/slightly seen (same level as Reference Example 1)
B: More dirt than A. C: Other than A and B, for example, obviously dirty.

<Measurement of total light transmittance>
The total light transmittance of the obtained film was measured in accordance with ISO-13468-1 (measurement conditions: D65 light source, 10° visual field).
For the measurement, a haze meter HM-150 manufactured by Murakami Color Research Laboratory was used.
The total light transmittance is expressed in %.

<Haze measurement>
The haze (%) of the obtained film was measured using a haze meter under conditions of a D65 light source and a 10° visual field.
For the measurement, a haze meter HM-150 manufactured by Murakami Color Research Laboratory was used.

10 Transparent conductive film 11 Electrode layer (transparent conductive film)
12 Substrate 13 Adhesive layer 14 Protective film

Claims (10)

A resin composition comprising 20 to 80 parts by mass of an aromatic polycarbonate resin, 80 to 20 parts by mass of a polyarylate resin, and a metal salt of a phosphate compound,
When the resin composition is molded into a film having a thickness of 200 μm, the haze is 1.0% or less;
The composition contains 0.03 to 0.075 parts by mass of a metal salt of a phosphate compound per 100 parts by mass of the total of the aromatic polycarbonate resin and the polyarylate resin,
The resin composition, wherein the metal salt of a phosphate compound comprises a compound represented by formula (P1) and a compound represented by formula (P2).
Formula (P1) Formula (P2)

(In formula (P1) and formula (P2), each R ^x independently represents a linear or branched alkyl group having 3 to 30 carbon atoms.) The resin composition of claim 1 , wherein the metal salt of a phosphate compound comprises a zinc salt of a phosphate compound. The resin composition according to claim 1 or 2 , wherein the polyarylate resin has a weight average molecular weight of 30,000 to 55,000. The resin composition according to any one of claims 1 to 3 , wherein the resin composition has a glass transition temperature of 155°C or higher as measured by differential scanning calorimetry. The resin composition according to any one of claims 1 to 4 , wherein the aromatic polycarbonate resin has a weight average molecular weight of 20,000 to 38,000. A film formed from the resin composition according to any one of claims 1 to 5 . The film of claim 6 , having a thickness of 25 to 500 μm. A multilayer film comprising the film of claim 6 or 7 . 9. The multilayer film according to claim 8 , having at least one of a hard coat layer, an antiblocking layer, an adhesive layer, an adhesion layer, and an index matching layer on one or both sides of the film. A method for producing a film, comprising extruding the resin composition according to any one of claims 1 to 5 and transporting the extrudate through a roll to form the film.