Resin composition, film, and multilayer film

Abstract

To provide a resin composition that contains an aromatic polycarbonate resin having a terminal structure containing an ester group, wherein, even when heated, the resin composition barely shows an increase in high-molecular-weight component; and to provide a film including the resin composition, and a multilayer film.SOLUTION: A resin composition contains an aromatic polycarbonate resin having a terminal structure containing an ester group, and a cyclic ether compound.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition, and a film and a multilayer film using the resin composition. [Background technology]

[0002] Aromatic polycarbonate resins are not only highly transparent, but also easier to process and more impact-resistant than glass, and do not emit toxic gases as compared to other plastic materials. For these reasons, they are widely used in a variety of fields, and are also used as materials for films and thermoformed products.

[0003] One example of thermoforming is the molding of a thermoplastic resin (plastic) film that has been heated and softened using a mold. Known thermoforming methods include vacuum molding, in which a heated film is placed over a mold and fixed, creating a vacuum between the mold and the film, and compressed air molding, in which compressed air is used to pressurize the film. When thermoforming a thermoplastic resin film, it must be heated to a temperature above the glass transition temperature or softening temperature of the thermoplastic resin. On the other hand, Patent Document 1 discloses a polycarbonate resin suitable for thermoforming, which uses parahydroxybenzoic acid hexadecyl ester as an end-capping agent. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2019-002023 Summary of the Invention [Problem to be solved by the invention]

[0005] However, as a result of investigations conducted by the present inventors, it was found that when an attempt is made to produce a film using an aromatic polycarbonate resin having a terminal structure containing an ester group, as described in Patent Document 1, for example, high molecular weight substances are produced due to thermal retention in the molding machine. The present invention aims to solve these problems and to provide a resin composition containing an aromatic polycarbonate resin having a terminal structure containing an ester group, in which high-molecular-weight components are unlikely to increase even when the resin composition is left in a heated state, as well as a film and a multilayer film using the resin composition. [Means for solving the problem]

[0006] As a result of investigations conducted by the present inventors in light of the above-mentioned problems, it has been found that the above-mentioned problems can be solved by blending a specific cyclic ether compound. Specifically, the above-mentioned problems have been solved by the following means. <1> A resin composition comprising an aromatic polycarbonate resin having a terminal structure containing an ester group and a cyclic ether compound. <2> The aromatic polycarbonate resin having a terminal structure containing an ester group includes an aromatic polycarbonate resin having a terminal structure represented by formula (1): <1> The resin composition according to claim 1. [ka] (In formula (1), R 1 represents an alkyl group having 8 to 36 carbon atoms or an alkenyl group having 8 to 30 carbon atoms. 2 each independently represents a halogen atom, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 12 carbon atoms. n represents an integer of 0 to 4. * represents a bonding site to another site. <3> The cyclic ether compound is contained in an amount of 0.001 to 0.300 parts by mass relative to 100 parts by mass of the aromatic polycarbonate resin. <1> or <2> The resin composition according to claim 1. <4> The cyclic ether compound is an epoxy compound. <1> ~ <3> The resin composition according to any one of the above. <5> the aromatic polycarbonate resin having a terminal structure containing an ester group has a glass transition temperature of 140°C or lower as measured by differential scanning calorimetry; <1> ~ <4> The resin composition according to any one of the above. <6> <1> ~ <5> A film formed from the resin composition according to any one of the above. <7> The thickness is 25 to 500 μm. <6> The film according to claim 1. <8> <6> or <7> A multilayer film comprising the film described in . <9> The film has at least one layer selected from the group consisting of a hard coat layer, an anti-blocking layer, an adhesive layer, an adhesive layer, and an index matching layer on one or both sides thereof. <8> The multilayer film according to claim 1. [Effects of the Invention]

[0007] The present invention makes it possible to provide a resin composition containing an aromatic polycarbonate resin having a terminal structure containing an ester group, in which the resin composition is less likely to contain high-molecular-weight components even when heated, as well as a film and a multilayer film using the resin composition. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment for carrying out 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 only this embodiment. In this specification, the symbol "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, when a notation does not specify whether they are substituted or unsubstituted, it includes both groups (atomic groups) that have no substituents and groups (atomic groups) that have substituents. For example, the term "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, when a notation does not specify whether they are substituted or unsubstituted, it is preferable that they be unsubstituted. In this specification, unless otherwise specified, the weight average molecular weight is a polystyrene-equivalent value measured by GPC (gel permeation chromatography). The term "film" as used herein includes flat molded articles such as sheets. The term "film" refers to a generally flat molded article that is thin relative to its length and width. The term "film" as used herein may be either single-layer or multi-layer. If the standards shown in this specification differ depending on the year and the measurement method, etc., they will be based on the standards as of January 1, 2021, unless otherwise stated.

[0009] The resin composition of this embodiment is characterized by containing an aromatic polycarbonate resin having a terminal structure containing an ester group and a cyclic ether compound. This configuration makes it possible to prevent the increase of high-molecular-weight components even when the resin is left in a heated state. It is believed that the high-molecular-weight components are generated when the ester bonds at the terminals of the polycarbonate resin are broken during heating. It is believed that when the ester bonds at the terminals of the polycarbonate resin are broken, recombination with other esters occurs, resulting in a high molecular weight. In this embodiment, it is believed that by incorporating a cyclic ether compound, even if the ester bonds are broken, the acid derived from the ester bonds is trapped by the cyclic ether compound, thereby effectively suppressing the increase in molecular weight. Furthermore, during heating, gel-like substances may also be generated. This gel-like substance is presumably generated when the ester bonds at the terminals of the polycarbonate resin are broken, resulting in three-dimensional transesterification. Such gels affect the appearance of the resulting molded product. In this embodiment, the generation of such gels can also be effectively suppressed.

[0010] <Aromatic polycarbonate resin having a terminal structure containing an ester group> The resin composition of this embodiment contains an aromatic polycarbonate resin having a terminal structure containing an ester group. Aromatic polycarbonate resins having a terminal structure containing an ester group are prone to transesterification, but in this embodiment, by incorporating a cyclic ether compound, even if the aromatic polycarbonate resin having a terminal structure containing an ester group is thermally retained, it is possible to make it less likely to generate high molecular weight compounds. Furthermore, while heating aromatic polycarbonate resins having a terminal structure containing an ester group has traditionally tended to generate gel-like insoluble matter, this can be effectively suppressed in this embodiment.

[0011] The terminal structure containing an ester group is not particularly limited as long as it contains an ester structure, but is preferably a group consisting of a combination of an ester group and a hydrocarbon group, or a combination of an ester group, a hydrocarbon group, and -O-. The formula weight of the terminal structure containing an ester group is preferably 100 or more, and is preferably 1500 or less, more preferably 1000 or less, even more preferably 800 or less, and may be 500 or less. In the present embodiment, the terminal structure containing an ester group preferably has a terminal structure represented by formula (1). By using an aromatic polycarbonate resin having a terminal structure represented by formula (1), the glass transition temperature of the aromatic polycarbonate resin can be lowered. [ka] (In formula (1), R 1 represents an alkyl group having 8 to 36 carbon atoms or an alkenyl group having 8 to 30 carbon atoms. 2each independently represents a halogen atom, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 12 carbon atoms. n represents an integer of 0 to 4. * represents a bonding site to another site.

[0012] R 1 represents an alkyl group having 8 to 36 carbon atoms or an alkenyl group having 8 to 30 carbon atoms, preferably an alkyl group or alkenyl group having 10 or more carbon atoms, more preferably an alkyl group or alkenyl group having 12 or more carbon atoms, and even more preferably an alkyl group or alkenyl group having 14 or more carbon atoms. This lowers the glass transition temperature of the resin and improves the heat bending properties of the film and multilayer film. In addition, R 1 R is preferably an alkyl or alkenyl group having 22 or less carbon atoms, and more preferably an alkyl or alkenyl group having 18 or less carbon atoms. 1 is preferably an alkyl group. The alkyl group and alkenyl group are preferably linear or branched alkyl or alkenyl groups, and more preferably linear alkyl or alkenyl groups. In this embodiment, R 1 is particularly preferably a hexadecyl group. Also, R 1 may be located at any of the meta, para, or ortho positions, but is preferably located at the meta or para position, and more preferably at the para position.

[0013] R 2 each independently represents a halogen atom, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and is preferably a fluorine atom, a chlorine atom, a methyl group, an ethyl group, or a phenyl group, and more preferably a fluorine atom, a chlorine atom, or a methyl group. n represents an integer of 0 to 4, preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 0.

[0014] The terminal structure represented by formula (1) can be added to an aromatic polycarbonate resin by using a terminal blocking agent such as parahydroxybenzoic acid hexadecyl ester. For details, see paragraphs 0022 to 0030 of JP 2019-002023 A, the contents of which are incorporated herein by reference. The aromatic polycarbonate resin having a terminal structure represented by formula (1) in this embodiment may have one type of terminal structure represented by formula (1), or two or more types of terminal structures represented by formula (1).

[0015] In this embodiment, the aromatic polycarbonate resin having a terminal structure containing an ester group is preferably a bisphenol polycarbonate resin, more preferably a bisphenol A polycarbonate resin. In addition, it is preferable that 50 mol % or more of the bisphenol polycarbonate resin has at least one terminal structure represented by formula (1). Furthermore, when the aromatic polycarbonate resin has a terminal structure represented by formula (1), the terminal structure preferably consists solely of the terminal structure represented by formula (1).

[0016] The bisphenol A polycarbonate resin may also have structural units other than carbonate structural units derived from bisphenol A and its derivatives. Examples of dihydroxy compounds constituting such other structural units include the aromatic dihydroxy compounds described in paragraph 0014 of JP 2018-154819 A, the contents of which are incorporated herein by reference. In the bisphenol polycarbonate resin of the present embodiment, carbonate structural units derived from bisphenol A and its derivatives preferably account for 90% by mass or more of all structural units excluding terminal structures, more preferably 95% by mass or more, and even more preferably 97% by mass or more.

[0017] The method for producing the bisphenol A polycarbonate resin is not particularly limited, and any method can be used, such as interfacial polymerization, melt transesterification, pyridine method, ring-opening polymerization of a cyclic carbonate compound, and solid-phase transesterification of a prepolymer.

[0018] The weight-average molecular weight of the aromatic polycarbonate resin having a terminal structure containing an ester group is not particularly limited, but is preferably 10,000 or more, more preferably 20,000 or more, even more preferably 30,000 or more, even more preferably 40,000 or more, and even more preferably 50,000 or more. By setting the weight-average molecular weight at or above the lower limit, the impact resistance of the film and the suppression of flow marks during molding tend to be further improved. Furthermore, the weight-average molecular weight of the aromatic polycarbonate resin having a terminal structure containing an ester group is preferably 200,000 or less, more preferably 150,000 or less, even more preferably 100,000 or less, even more preferably 80,000 or less, and even more preferably 60,000 or less. By setting the weight-average molecular weight at or below the upper limit, the moldability of the multilayer body tends to be improved.

[0019] The glass transition temperature of the aromatic polycarbonate resin having a terminal structure containing an ester group used in this embodiment is preferably 140°C or lower, more preferably 139°C or lower, even more preferably 135°C or lower, and may be 132°C or lower, or even 125°C or lower. By setting the glass transition temperature to the upper limit or lower, the hot bending formability of the multilayer body tends to be further improved. Furthermore, the glass transition temperature of the aromatic polycarbonate resin having a terminal structure containing an ester group used in this embodiment is preferably 121°C or higher, more preferably 122°C or higher, and even more preferably 123°C or higher. By setting the glass transition temperature to the lower limit or higher, the durability in environmental resistance tests such as wet heat tests and high-temperature tests tends to be further improved.

[0020] The content of the aromatic polycarbonate resin in the resin composition of this embodiment is preferably 70% by mass or more, more preferably 80% by mass or more, and may even be 90% by mass or more, or 95% by mass or more. The upper limit of the content of the aromatic polycarbonate resin in the resin composition is, for example, 99.99% by mass or less. The resin composition of the present embodiment may contain only one type of aromatic polycarbonate resin, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0021] <Cyclic ether compounds> The resin composition of the present embodiment contains a cyclic ether compound. It is presumed that the presence of the cyclic ether compound traps the acid derived from the ester bond even if the ester bond of the aromatic polycarbonate resin is broken, thereby effectively suppressing polymerization of the aromatic polycarbonate resin.

[0022] The cyclic ether compound refers to a compound containing a cyclic ether group. The cyclic ether compound may contain only one cyclic ether group or two or more cyclic ether groups in one molecule, but preferably contains one to four cyclic ether groups, more preferably contains one to three cyclic ether groups, and even more preferably contains two cyclic ether groups. The cyclic ether compound is preferably a compound having a 3- to 10-membered cyclic ether group, more preferably an epoxy compound or an oxetanyl compound, and even more preferably an epoxy compound. The molecular weight of the cyclic ether compound is not particularly limited, but is preferably 100 or more, and is preferably 1500 or less, more preferably 1000 or less, even more preferably 800 or less, and may be 500 or less.

[0023] The cyclic ether compound is preferably an alicyclic epoxy compound, which can more easily undergo ring opening and effectively trap the acid derived from the ester bond.

[0024] The cyclic ether compound used in this embodiment is preferably a compound represented by formula (2), a compound represented by formula (3), or a compound represented by formula (4), and more preferably a compound represented by formula (2) and / or a compound represented by formula (4). Formula (2) [ka] (In formula (2), A 1 represents a divalent organic group.

[0025] In equation (2), A 1 is preferably a hydrocarbon group having 1 to 10 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, and more preferably an alkylene group having 1 to 10 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups. The alkylene group may be linear, branched, or cyclic, and is preferably linear or branched, and more preferably linear. Preferred examples of the compound represented by formula (2) include the following compounds. [ka]

[0026] Formula (3) [ka] (In formula (3), A 2 and A 3 each independently represents a divalent organic group.

[0027] In equation (3), A 2 are each independently preferably a hydrocarbon group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and more preferably an alkylene group having 1 to 3 carbon atoms. In equation (3), A 3is preferably a hydrocarbon group having 1 to 20 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, and even more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, -O-, or a group consisting of a combination of two or more of the above groups. 3 The end (next to the oxygen atom) of is preferably a hydrocarbon group having 1 to 20 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 12 carbon atoms, and even more preferably an alkylene group having 1 to 10 carbon atoms. Preferred examples of the compound represented by formula (3) include the following compounds. [ka] n is an arbitrary integer, and is preferably 1 to 11. [ka]

[0028] Formula (4) [ka] (In formula (4), A 4 and A 5 R each independently represents a divalent organic group. a is an alkyl group having 1 to 5 carbon atoms, and nb is 0 or 1.

[0029] In equation (4), A 4are each independently preferably a hydrocarbon group having 1 to 20 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, even more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, or a group consisting of a combination of two or more of the above groups, still more preferably an alkylene group having 1 to 10 carbon atoms, still more preferably an alkylene group having 1 to 3 carbon atoms, and still more preferably an ethylene group or a methylene group. In equation (4), A 5 is preferably a hydrocarbon group having 1 to 20 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, and even more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, or a group consisting of a combination of two or more of the above groups. 5 The end (next to the oxygen atom) of is preferably a hydrocarbon group having 1 to 20 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 12 carbon atoms, even more preferably an alkylene group having 1 to 10 carbon atoms, and still more preferably an alkylene group having 1 to 3 carbon atoms.

[0030] R a is preferably an alkyl group having 1 to 3 carbon atoms, and is preferably a methyl group or an ethyl group. nb is preferably 1. Preferred examples of the compound represented by formula (4) include the following compounds. [ka]

[0031] In addition to the above, preferred examples of the epoxy compound used in this embodiment include the compounds described in paragraphs 0043 to 0069 of JP 2021-038306 A and paragraphs 0023 to 0037 of JP 2021-031658 A, the contents of which are incorporated herein by reference.

[0032] The content of the cyclic ether compound in the resin composition of this embodiment is preferably 0.001 parts by mass or more, more preferably 0.003 parts by mass or more, even more preferably 0.005 parts by mass or more, even more preferably 0.007 parts by mass or more, and even more preferably 0.009 parts by mass or more, relative to 100 parts by mass of the aromatic polycarbonate resin. By setting the content at or above the lower limit, the effect of trapping broken ester bonds tends to be further improved. Furthermore, the content of the cyclic ether compound is preferably 0.300 parts by mass or less, more preferably 0.200 parts by mass or less, even more preferably 0.100 parts by mass or less, even more preferably 0.050 parts by mass or less, and even more preferably 0.040 parts by mass or less, relative to 100 parts by mass of the aromatic polycarbonate resin. Setting the content at or below the upper limit can effectively prevent the cyclic ether compound from forming a crosslinked structure. The resin composition of the present embodiment may contain only one type of cyclic ether compound, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0033] <Antioxidants> The resin composition of the present embodiment may contain an antioxidant. Examples of antioxidants include phenol-based antioxidants, amine-based antioxidants, phosphorus-based antioxidants, and thioether-based antioxidants, and it is preferable to use at least one selected from phosphorus-based antioxidants and phenol-based antioxidants. As the antioxidant, phosphorus-based antioxidants are particularly preferable. It is also preferable to use a phosphorus-based antioxidant and a phenol-based antioxidant (more preferably a hindered phenol-based antioxidant) in combination.

[0034] The phosphorus-based antioxidant is not particularly limited as long as it is an antioxidant containing a phosphorus atom. Specific examples of phosphorus-based antioxidants include phosphorus oxoacids such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; metal acid pyrophosphates such as sodium acid pyrophosphate, potassium acid pyrophosphate, and calcium acid pyrophosphate; phosphates of Group 1 or Group 2B metals such as potassium phosphate, sodium phosphate, cesium phosphate, and zinc phosphate; phosphate compounds, phosphite compounds, and phosphonite compounds, with phosphite compounds being particularly preferred. By selecting a phosphite compound, a resin sheet with improved discoloration resistance and continuous productivity can be obtained. For details of phosphorus-based antioxidants, please refer to the descriptions in paragraphs 0058 to 0064 of JP 2018-090677 A, the contents of which are incorporated herein by reference.

[0035] A preferred embodiment of the phosphorus-based antioxidant used in the present invention is a phosphorus-based antioxidant having a di- or triaryl phosphite structure. In this embodiment, a phosphorus-based antioxidant represented by formula (P) is preferred. Formula (P) [ka] (In formula (P), R p each independently represents an aryl group having 6 to 30 carbon atoms. R p may be an aryl group having a substituent, and is preferably an aryl group substituted with an alkyl group. The aryl group is preferably a phenyl group. The alkyl group as the substituent is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a butyl group, and even more preferably a t-butyl group. Examples of the phosphorus-based antioxidant represented by formula (P) include ADK STAB 2112, ADK STAB 1178, and ADK STAB TPP, all manufactured by ADEKA Corporation. In this embodiment, phosphorus-based antioxidants having a pentaerythritol diphosphite structure can also be preferably used, and details thereof are exemplified by compounds described in WO 2013 / 088796, the contents of which are incorporated herein by reference.

[0036] The phenolic antioxidant may be, for example, a hindered phenolic antioxidant.As such a phenolic antioxidant, the phenolic antioxidant described in paragraph 0041 of JP-A-2019-002023 and the phenolic antioxidant described in paragraphs 0033-0034 of JP-A-2019-056035 are preferably used, and the contents thereof are incorporated herein by reference.

[0037] When the resin composition of this embodiment contains an antioxidant, the lower limit of the antioxidant content is preferably 0.001 parts by mass or more, more preferably 0.005 parts by mass or more, and even more preferably 0.008 parts by mass or more, relative to 100 parts by mass of the aromatic polycarbonate resin. The upper limit of the antioxidant content is preferably 1 part by mass or less, more preferably 0.8 parts by mass or less, and even more preferably 0.5 parts by mass or less, relative to 100 parts by mass of the aromatic polycarbonate resin. The resin composition of the present embodiment may contain only one type of antioxidant, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0038] <Release agent> The resin composition of the present embodiment may contain a release agent. By containing a release agent, a film with better 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. Other examples of the release agent that can be used include the release agents described in paragraph 0032 of JP-A No. 2017-226848 and paragraph 0056 of JP-A No. 2018-199745, the contents of which are incorporated herein by reference.

[0039] 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 is 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, relative to 100 parts by mass of the aromatic polycarbonate 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.

[0040] <Other ingredients> In addition to the above, the resin composition of the present embodiment may contain an ester exchange inhibitor, a flame retardant, a flame retardant aid, an ultraviolet absorber, a colorant, an antistatic agent, a fluorescent brightener, an antifogging agent, a flow improver, a plasticizer, a dispersant, an antibacterial agent, an antiblocking agent, an impact improver, a sliding improver, a hue improver, an acid trapping agent, etc. These components may be used alone or in combination of two or more. When contained, the total amount of the other components is preferably 0.001 to 5 mass %, more preferably 0.001 to 2 mass %, and even more preferably 0.01 to 1 mass % of the resin composition. Anti-blocking refers to the effect of suppressing adhesion between films, and can be achieved by adding an anti-blocking agent, etc.

[0041] <Method of manufacturing resin composition> The method for producing the resin composition of the present embodiment is not limited, and a wide range of known production methods can be employed. A specific example of such a method is to premix a polycarbonate resin, a cyclic ether compound, and other components that are added as needed using various mixers such as a tumbler, a Henschel mixer, or a super mixer, and then melt-knead the mixture using a mixer such as a Banbury mixer, a roll, a Brabender mixer, a single-screw kneading extruder, a twin-screw kneading extruder, or a kneader.

[0042] <Film> The film of this embodiment is formed from the resin composition of this 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 the thickness equal to or greater than the lower limit, breakage during film formation tends to be suppressed. Furthermore, 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 the thickness equal to or less than the upper limit, bending resistance tends to be further improved.

[0043] The film of this embodiment can be used as a multilayer film containing the film of this embodiment (single layer film). As the layer contained in the multilayer film, known layers can be used in addition to the film of this embodiment. The film of this embodiment is used as a multilayer film having at least one layer selected from the group consisting of a hard coat layer, an antiblocking layer, an adhesive layer, an adhesive layer, and an index matching layer on one 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, in which 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 above 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 No. 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 No. 2018-058233, and the description of the application of the transparent conductive film described in paragraphs 0106 and 0107 can be referred to, the contents of which are incorporated herein by reference.

[0044] When the film of this embodiment is a multilayer film, its thickness is preferably 26 μm or more, more preferably 36 μm or more, even more preferably 41 μm or more, even more preferably 46 μm or more, and even more preferably 51 μm or more. By setting the thickness at or above the lower limit, breakage of the film during transport can be effectively suppressed. Furthermore, the thickness of the multilayer film is preferably 510 μm or less, more preferably 410 μm or less, even more preferably 310 μm or less, even more preferably 260 μm or less, and even more preferably 210 μm or less. By setting the thickness at or below the upper limit, cracking during bending can be effectively suppressed. The film of this embodiment is also preferably used for applications other than those mentioned above.

[0045] The film of the present embodiment is produced using the resin composition of the present embodiment according to a known film production method. Preferably, the film of the present embodiment is produced by a method including extruding the resin composition of the present embodiment and conveying it through a roll to form the film.

[0046] 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 producing the multilayer film. For example, during melt extrusion using a T-die, the materials may be laminated inside the die to form a film, or may be formed into a film and then laminated to form a multilayer film. [Example]

[0047] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, processing details, 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.

[0048] 1.Raw materials (A) Aromatic polycarbonate resin A1: T-1380, bisphenol A polycarbonate resin using parahydroxybenzoic acid hexadecyl ester as an end-capping agent, manufactured by Mitsubishi Gas Chemical Company, Inc., weight average molecular weight: 55,000, Tg: 130°C

[0049] <Measurement of glass transition temperature (Tg)> The glass transition temperature (Tg) of the aromatic polycarbonate resin was measured by performing two cycles of temperature increase and decrease according to the following differential scanning calorimetry (DSC) measurement conditions, and measuring the glass transition temperature during the second temperature increase cycle. The starting glass transition temperature was determined as the intersection of a line drawn by extending the low-temperature baseline toward the high temperature side with a tangent to the inflection point, and the ending glass transition temperature was determined as the intersection of a line drawn by extending the high-temperature baseline toward the low temperature side with a tangent to the inflection point. The midpoint between the starting and ending glass transition temperatures was determined as the glass transition temperature (Tg). The measurement conditions were: starting temperature: 30°C, heating rate: 10°C / min, final temperature: 250°C, cooling rate: 20°C / min. The measurement device used was a differential scanning calorimeter (DSC, manufactured by Hitachi High-Tech Science Corporation, "DSC7020").

[0050] (B) Cyclic ether compounds B1: Daicel, Celloxide 2021P [ka] B2: Toagosei Co., Ltd., Aron Oxetane, OXT-121 [ka]

[0051] (C) Antioxidants C1: ADEKA Corporation, Adekastab (AS) 2112, tris(2,4-di-tert-butylphenyl) phosphite C2: Adekastab AO-60, manufactured by ADEKA Corporation, tetrakis[3-(3',5'-di-tert-butyl-4-hydroxyphenyl)propionic acid]pentaerythritol (D) Mold release agent D1: Riken Vitamin Co., Ltd., Rikemal S-100A, glycerin monostearate

[0052] 2. Examples 1 and 2, Comparative Examples 1 to 5 <Production of aromatic polycarbonate resin film> An aromatic polycarbonate resin film was produced by the following method. The components listed in Table 1 were weighed out in the amounts listed in Table 1 (Table 1 shows the amounts in parts by weight). After mixing for 15 minutes in a tumbler, the mixture was extruded into a molten state using a T-die melt extruder consisting of a vented twin-screw segment extruder (Toyo Seiki Co., Ltd., "2D30W2") with a barrel diameter of 25 mm and a screw length / distance ratio of 30 mm at a throughput rate of 8 kg / h and a screw rotation speed of 100 rpm. The extruded material was then cooled and solidified only by the first roll of a film / sheet take-up device (Toyo Seiki Co., Ltd., "FT3W20") to produce an aromatic polycarbonate resin film. The cylinder / die head temperature was 280°C, and the roll temperature was 120°C. The final film thickness was adjusted to 100 μm by changing the roll speed of the first roll.

[0053] The obtained film was subjected to the following tests, and the results are shown in Table 1.

[0054] <Insoluble matter after heating test> The resulting film was heated in a vacuum dryer (Yamato Scientific, DP23) under nitrogen at 300°C for 16 hours, after which 5 g was dissolved in 50 mL of dichloromethane and suction filtered using a 10 μm membrane filter. The mass of the insoluble material collected on the filter was measured. This insoluble material contained a gel-like substance formed by the cleavage of the ester bonds at the terminals of the polycarbonate resin, resulting in three-dimensional transesterification. The evaluation was as follows: A: Less than 5 mg B: 5 mg or more but less than 20 mg C:20mg or more

[0055] <High molecular weight substance after heating test> The obtained film was heated in a vacuum dryer (Yamato Scientific, DP23) under nitrogen at 300°C for 16 hours. The film was measured before and after heating by gel permeation chromatography, normalized to the maximum intensity of the obtained spectrum, and evaluated as the difference in peak intensity at a polystyrene-equivalent molecular weight of 490,000. The measurement was performed as follows. The gel permeation chromatography apparatus used was an LC-20AD system (Shimadzu Corporation), and an LF-804 (Shodex Corporation) was connected to the column. The column temperature was 40°C. The detector used was an RID-10A (Shimadzu Corporation) RI detector. Chloroform was used as the eluent, and a calibration curve was prepared using standard polystyrene (Tosoh Corporation). If the above gel permeation chromatography device, column, and detector are difficult to obtain, measurement can be performed using other devices with equivalent performance. The evaluation was as follows: A: Less than 0.2% B: 0.2% or more

[0056] [Table 1]

Claims

1. A transparent conductive film having a protective layer, an adhesive layer, a substrate, and an electrode layer in this order, at least one of the substrate and the protective layer is a film formed from a resin composition containing an aromatic polycarbonate resin having a terminal structure containing an ester group and a cyclic ether compound; The transparent conductive film has a total thickness of 26 to 310 μm.

2. The transparent conductive film according to claim 1 , wherein the aromatic polycarbonate resin having a terminal structure containing an ester group comprises an aromatic polycarbonate resin having a terminal structure represented by formula (1): 【Chemistry 1】 (In formula (1), R １ represents an alkyl group having 8 to 36 carbon atoms or an alkenyl group having 8 to 30 carbon atoms. ２ each independently represents a halogen atom, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 12 carbon atoms; n represents an integer of 0 to 4; * represents a bonding site to another site.

3. 3. The transparent conductive film according to claim 1, wherein the cyclic ether compound is contained in an amount of 0.001 to 0.300 parts by mass per 100 parts by mass of the aromatic polycarbonate resin.

4. The transparent conductive film according to any one of claims 1 to 3, wherein the cyclic ether compound is an epoxy compound.

5. The transparent conductive film according to any one of claims 1 to 4, wherein the aromatic polycarbonate resin having a terminal structure containing an ester group has a glass transition temperature of 140°C or lower as measured by differential scanning calorimetry.

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