JP7799996B2 - Film, multilayer body, and transparent conductive film - Google Patents

Description

The present invention relates to a film, a multilayer body, and a transparent conductive film.

Transparent conductive films are used in film sensors of touch panels, electronic paper, dye-sensitized solar cells, touch sensors, etc. As shown in Fig. 1 , for example, 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.
Specifically, Patent Document 1 discloses a transparent conductive film laminate having, in this order, an adhesive layer, a film substrate, and a transparent conductive film on a protective film, wherein at least one of the film substrate and the protective film has an uneven portion on the surface of the adhesive layer in each end region from one end and the other end to a widthwise inner 100 mm, the effective roughness R1 of the uneven portion in each end region being 0.1 to 20 μm, and the adhesive layer is provided in the widthwise direction from a position where the distance between the uneven portion in one end region and the uneven portion in the other end region is 0 to 10 mm to a position where the distance between the uneven portion in the one end region and the uneven portion in the other end region is 0 to 10 mm. It also discloses that the protective film is made of a polycarbonate resin.

Japanese Patent Application Laid-Open No. 2018-152187

As described above, a protective film is typically used for transparent conductive films. Such a protective film is used to protect the substrate when transporting a multilayer structure having an electrode layer and a substrate. More specifically, transparent conductive films are often produced industrially using a roll-to-roll process, which requires improved film transportability and prevention of winding wrinkles. Film transport problems and winding wrinkles can be reduced by suppressing adhesion (blocking) between films. Therefore, to prevent blocking on the side opposite the electrode layer of a transparent conductive film, the protective film for the transparent conductive film is required to have sufficient sliding properties to prevent the films from stacking. Furthermore, since transparent conductive films are typically subjected to in-line defect inspection with the protective film attached, the film is required to prevent the image from becoming blurred when projected with a light source.
The present invention aims to solve these problems and to provide a film, a multilayer body, and a transparent conductive film that have excellent sliding properties and do not blur images when projected with a light source.

In light of the above-mentioned problems, the present inventors have conducted research and found that the above-mentioned problems can be solved by adjusting the surface of the film to have a predetermined surface shape.
Specifically, the above problems were solved by the following means.
<1> A film comprising 0.01 to 0.45 parts by mass of organic particles having a number average particle diameter of 1.0 to 4.8 μm per 100 parts by mass of an amorphous thermoplastic resin, wherein Spd on the film surface is 65 to 400 particles, S10z is 0.40 to 2.50 μm, Spd indicates the number of convex portions (unit: particles) per ¹ mm2 of the film, S10z indicates the sum of S5p and S5v, S5p indicates the average local height (unit: μm) of the top five highest peaks, and S5v indicates the average local depth (unit: μm) of the bottom five deepest valleys, S5p, S5v, and Spd are values specified in ISO25718-2:2012, and the film has a thickness of 20 μm or more and less than 500 μm.
<2> The film according to <1>, wherein the total light transmittance of the film under conditions of a D65 light source and a 10° field of view is 86.0% or more.
<3> The film according to <1> or <2>, wherein the haze of the film under conditions of a D65 light source and a 10° field of view is less than 2.0%.
<4> The film according to any one of <1> to <3>, wherein the organic particles have a number average particle size of 2.6 to 4.8 μm.
<5> The film according to any one of <1> to <4>, wherein the content of the organic particles is 0.01 to 0.40 parts by mass per 100 parts by mass of the amorphous thermoplastic resin.
<6> The film according to any one of <1> to <5>, wherein the organic particles are rubber-free particles.
<7> The film according to any one of <1> to <6>, wherein at least one surface of the film has a dynamic friction coefficient of 1.00 or less against a film having a root-mean-square roughness of 0.093 μm.
<8> The film according to any one of <1> to <7>, which is a single-layer film.
<9> A multilayer body comprising the film according to any one of <1> to <8> and at least one other layer.
<10> The multilayer body according to <9>, wherein the other layer includes an adhesive layer.
<11> A transparent conductive film having a protective layer, an adhesive layer, a substrate, and an electrode layer in this order, wherein at least one of the substrate and the protective layer is the film according to any one of <1> to <8>.

The present invention makes it possible to provide a film, multilayer body, and transparent conductive film that have excellent sliding properties and do not blur images when projected with a light source.

FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of a transparent conductive film. Figure 2(a) is a schematic diagram showing a state in which a smooth resin film is slid over another smooth resin film, and Figure 2(b) is a schematic diagram showing a state in which a resin film with a finely textured surface is slid over a resin film with a finely textured surface.

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 only this 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.
The term "film" as used herein refers to a generally flat shaped body that is thin relative to its length and width, and includes a sheet. The term "film" as used herein may be either a single layer or a multilayer.
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.

The film of the present embodiment is a film containing 0.01 to 0.45 parts by mass of organic particles having a number average particle diameter of 1.0 to 4.8 μm per 100 parts by mass of an amorphous thermoplastic resin, and is characterized in that the film surface has an Spd of 65 to 400 particles, an S10z of 0.40 to 2.50 μm, and a thickness of 20 μm or more and less than 500 μm.
Here, Spd indicates the number of convex portions (unit: pieces) per 1 ^mm2 of film, S10z indicates the sum of S5p and S5v, S5p indicates the average local height (unit: μm) of the top five highest peaks, S5v indicates the average local depth (unit: μm) of the bottom five deepest valleys, and S5p, S5v, and Spd are values specified in ISO25718-2:2012.
This configuration makes it possible to provide a film that has excellent sliding properties and does not blur images when projected under light. Furthermore, it also provides a film with excellent winding properties, particularly a film that can be wound up with a good appearance without a masking film. It also provides a film with excellent transparency, such as a film with low haze and high total light transmittance.

To improve film transportability and prevent wrinkles during film wrapping, films may be required to have sufficient sliding properties to prevent stacking and even prevent films from adhering to each other (anti-blocking properties). Here, anti-blocking refers to the ability to easily peel films even when they are in close contact with each other. Figure 2(a) is a schematic diagram showing a smooth film sliding on another smooth film. Placing a smooth film on top of another smooth film like this results in no sliding. To impart sliding properties to a smooth film, it is possible to create fine irregularities on the film surface, as shown in the schematic diagram of Figure 2(b). By creating fine irregularities on the film surface in this way, the contact area between the films is reduced, achieving high sliding properties. In Figure 2, 21 denotes a film with a smooth surface, and 22 denotes a film with a finely irregular surface. Although Figure 2 shows two films with fine irregularities, sliding properties are generally achieved as long as at least one of the films has fine irregularities, as shown in the examples described below.

In order to provide the above-mentioned irregularities on the surface of such a film to ensure sliding properties, it is conceivable to incorporate particles into the thermoplastic resin. However, when inorganic particles are incorporated into the thermoplastic resin, transparency may be deteriorated. Furthermore, it has been found that depending on the particle size and film thickness, it may not be possible to successfully form irregularities on the film surface.
In this embodiment, in a film containing 0.01 to 0.45 parts by mass of organic particles having a number average particle diameter of 1.0 to 4.8 μm per 100 parts by mass of amorphous thermoplastic resin, by setting Spd on the film surface to 65 to 400 particles and S10z to 0.40 to 2.50 μm, it is possible to successfully obtain a film that has excellent sliding properties and does not blur images when projected when irradiated with a light source.

That is, Spd indicates the number of protrusions (unit: pieces) per ¹ mm2 of film, and is an index indicating the density of protrusions on the film surface. By setting Spd to 65 or more, protrusions are formed on the surface of the film, a moderate coefficient of dynamic friction is imparted, and sliding properties can be achieved. Also, by setting it to 400 or less, the number of protrusions is adjusted appropriately, and a dynamic coefficient of friction is effectively imparted, thereby achieving sliding properties.
On the other hand, S10z represents the sum of S5p and S5v, where S5p represents the average local height (unit: μm) of the top five peaks, and S5v represents the average local depth (unit: μm) of the top five valleys, starting from the deepest valley. In other words, S10z is an index indicating the height of the convex portions. In this embodiment, by setting the S10z value of the film surface to 0.40 μm or more, appropriate convex portions are provided on the film surface, achieving sliding properties. Furthermore, by setting the S10z value to 2.50 μm or less, light diffusion can be suppressed, and haze can be reduced.
In addition, in this embodiment, by using organic particles having a number average particle diameter, it is possible to prevent the image from becoming blurred when projected. In particular, even when the same amount of organic particles is used, the number of particles can be increased, which increases the number of protrusions on the film surface while improving the clarity of the image when projected, thereby improving the sliding properties.
On the other hand, in this embodiment, the blending amount of the organic particles is as small as 0.45 parts by mass or less relative to 100 parts by mass of the amorphous thermoplastic resin. By reducing the blending amount in this way, transparency can be further improved.
Furthermore, unlike inorganic particles, the use of organic particles can relatively reduce the difference in refractive index between the inorganic particles and the amorphous thermoplastic resin, resulting in a film with excellent transparency. In addition, inorganic particles tend to contain more foreign matter than organic particles, which tends to be more noticeable as foreign matter or black spots in the film, but the use of organic particles can effectively avoid these issues.
The details of this embodiment will be described below.

<Spd>
In the resin film of this embodiment, the Spd on the surface is 65 to 400. Spd indicates the number of convex portions (unit: pieces) per 1 ^mm2 of the resin film.
Spd can be adjusted by adjusting the material and particle size of the organic particles, the thickness of the film, and also by the production conditions, etc. In particular, when the film is produced by a roll-to-roll method, Spd can be adjusted by the surface hardness of the roll, the roll speed, the extrusion amount, etc.
The lower limit of Spd is preferably 100 or more, more preferably 120 or more, even more preferably 150 or more, even more preferably 200 or more, even more preferably 250 or more, particularly more preferably 300 or more, and even more particularly more preferably 350 or more. By setting it to the lower limit or more, the contact area between films is reduced, thereby suppressing stacking and improving the appearance when wound up. Furthermore, the upper limit of Spd is preferably 390 or less. By setting it to the upper limit or less, the number of protrusions on the film is appropriately adjusted, effectively imparting a dynamic friction coefficient and achieving slidability.
Spd is a value defined in ISO25718-2:2012 and is measured as described in the Examples below.

<S10z>
In the film of this embodiment, the surface S10z is 0.40 to 2.50 μm. S10z represents the sum of the average local height (S5p, unit: μm) of the top five highest peaks and the average local depth (S5v, unit: μm) of the top five deepest valleys. Here, height refers to the convex portions in the direction perpendicular to the film surface of the film, and depth refers to the concave portions in the direction perpendicular to the film surface of the film.
S10z can be adjusted by adjusting the material and particle size of the organic particles, the blending amount of the organic particles, as well as by the manufacturing conditions, etc. In particular, when the film is manufactured by a roll-to-roll method, S10z can be adjusted by the surface hardness of the rolls, the roll speed, the discharge amount during extrusion, etc.
The lower limit of S10z is preferably 0.41 μm or more, more preferably 0.42 μm or more, and may be 0.50 μm or more, or even 0.60 μm or more. By setting it to the lower limit or more, the sliding properties are improved and the appearance of the film when wound up is improved. Furthermore, the upper limit of S10z is preferably 2.20 μm or less, more preferably 2.00 μm or less, even more preferably 1.50 μm or less, even more preferably 1.20 μm or less, even more preferably 1.00 μm or less, even more preferably 0.90 μm or less, and particularly preferably 0.80 μm or less. By setting it to the upper limit or less, light is not diffused when projecting the film, and a clear image can be obtained. Furthermore, the haze of the resulting film can be reduced.
S10z is a value defined in ISO25718-2:2012 and is measured in accordance with the description of the examples described below.

<Film thickness>
The film of this embodiment has a thickness of 20 μm or more and less than 500 μm. By making the thickness less than 500 μm, the organic particles are more likely to be exposed to the surface, achieving slidability. In addition, the transparency of the film can be increased. Furthermore, the winding property of the film can be improved. In addition, by making the thickness 20 μm or more, the haze can be further reduced and transparency tends to be improved.
The thickness of the film of this embodiment may be 30 μm or more, or even 40 μm or more, and is preferably 400 μm or less, more preferably 300 μm or less, even more preferably 200 μm or less, still more preferably 100 μm or less, even more preferably 80 μm or less, and even more preferably 60 μm or less.
In particular, when a polycarbonate resin film is used, it has excellent winding properties at this thickness.
The thickness of the film is the average value of five arbitrary points.

<Other film properties>
In the film of this embodiment, the coefficient of dynamic friction of at least one surface against a film having a root-mean-square roughness of 0.093 μm is preferably 1.00 or less, more preferably 0.90 or less, more preferably 0.80 or less, and even more preferably 0.75 or less. The lower limit is not particularly specified, but may be, for example, 0.10 or more, or even 0.20 or more, 0.30 or more, 0.40 or more, or 0.50 or more.
The dynamic friction coefficient is a value measured under conditions of a thread speed of 100 mm/min and a load cell of 10 N, and specifically, is measured by the method described in the examples below.

The film of this embodiment preferably has a total light transmittance of 86.0% or more, more preferably 87.0% or more, even more preferably 89.0% or more, and may even have a total light transmittance of 90.0% or more under the condition of a D65 light source and a 10° field of view. The upper limit of the light transmittance is ideally 100%, but even if it is 95.0% or less, the required performance is sufficiently satisfied.
The total light transmittance is measured by the method described in the examples below.

The haze of the film of this embodiment, under conditions of a 10° field of view with a D65 light source, is preferably less than 2.0%, more preferably 1.8% or less, and even more preferably 1.5% or less. It may be less than 1.0%, 0.95% or less, or 0.8% or less. The lower limit is ideally 0%, but even 0.1% or more is practical. It is particularly preferable that the haze be in the above range when the thickness is 20 μm to 100 μm.
The haze is measured by the method described in the examples below.

<Amorphous thermoplastic resin>
The film of the present embodiment contains an amorphous thermoplastic resin. By using an amorphous thermoplastic resin, a film with excellent transparency can be obtained.
Examples of the amorphous thermoplastic resin used in this embodiment include polycarbonate resin, polyvinyl chloride, polystyrene, polymethyl methacrylate, acrylonitrile/butadiene/styrene (ABS resin) modified polyphenylene ether, polyethersulfone, polyetherimide, polyamideimide, polyolefin resin (COC, COP, PP, etc.), etc., and polycarbonate resin is preferred. Use of polycarbonate resin tends to further improve winding properties.
The amorphous thermoplastic resin refers to a thermoplastic resin that does not have a clear melting point as determined by differential scanning calorimetry.

The polycarbonate resin is not particularly limited as long as it contains an -[O-R-OC(=O)]- unit (where R is a hydrocarbon group, specifically an aliphatic group, an aromatic group, or one containing both an aliphatic group and an aromatic group, and further one having a linear or branched structure) that contains a carbonate bond in the molecular main chain. In this embodiment, the polycarbonate resin is preferably an aromatic polycarbonate resin, and more preferably a polycarbonate resin having a bisphenol skeleton. The use of such a polycarbonate resin achieves better heat resistance and toughness. In this embodiment, it is preferable that 90 mol % or more of the total structural units of the polycarbonate resin having a bisphenol skeleton are structural units having a bisphenol skeleton.

The viscosity average molecular weight (Mv) of the polycarbonate resin is preferably 10,000 or more, more preferably 12,000 or more, even more preferably 15,000 or more, and even more preferably 18,000 or more. By setting it to the lower limit or more, the durability of the substrate tends to be further improved. The upper limit of the viscosity average molecular weight (Mv) of the polycarbonate resin is preferably 50,000 or less, more preferably 40,000 or less, and even more preferably 30,000 or less. By setting it to the upper limit or less, the moldability of the substrate tends to be further improved.
The viscosity average molecular weight (Mv) means a value calculated from the intrinsic viscosity [η] (unit: dL/g) at 25°C using methylene chloride as a solvent and an Ubbelohde viscometer, using Schnell's viscosity formula, i.e., η = 1.23 × 10 ^-4 × Mv ^0.83 .
When two or more types of polycarbonate resins are used, the viscosity average molecular weight is the viscosity average molecular weight of the mixture.

A first embodiment of the polycarbonate resin in this embodiment is a polycarbonate resin having a structural unit represented by formula (A-1), and a representative example thereof is a bisphenol A polycarbonate resin.
In formula (A-1), ^X1 represents the following structure: In the formula, * represents the bonding position.
At least one of ^R5 and ^R6 is preferably a methyl group, and more preferably both are methyl groups.
Formula (A-1) is preferably represented by the following formula (A-2).

In the polycarbonate resin of the first embodiment, the content of the structural units represented by formula (A-1) is preferably 70 mol% or more, more preferably 80 mol% or more, and even more preferably 90 mol% or more, of all structural units excluding terminal groups. There is no particular upper limit, and 100 mol% may be structural units represented by formula (A-1).
The polycarbonate resin may contain other structural units. Examples of dihydroxy compounds constituting such other structural units include the aromatic dihydroxy compounds described in paragraph 0014 of JP-A-2018-154819, the contents of which are incorporated herein by reference.

A second embodiment of the polycarbonate resin in this embodiment is a polycarbonate resin containing a structural unit represented by formula (A-3), and a representative example thereof is a bisphenol AP type polycarbonate resin.
In formula (A-3), R ¹¹ to R ¹⁴ each independently represent a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an alkyl group having 1 to 9 carbon atoms (preferably 1 to 3), an aryl group having 6 to 12 carbon atoms (preferably 6 to 10), an alkoxy group having 1 to 5 carbon atoms (preferably 1 to 3), an alkenyl group having 2 to 5 carbon atoms (preferably 2 or 3), or an aralkyl group having 7 to 17 carbon atoms (preferably 7 to 11). 1 represents an integer of 0 to 5 (preferably 0 or 1, more preferably 0). m and n each independently represent an integer of 0 to 4 (preferably 0 or 1, more preferably 0). In the formula, * represents the bonding position to other structural units or terminal groups.

The structural unit represented by formula (A-3) is preferably a structural unit represented by the following formula (A-4): In the formula, * indicates the bonding position to other structural units or terminal groups.
R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , l, m, and n are the same as defined in formula (A-3).

The structural unit represented by formula (A-4) is preferably a structural unit represented by the following formula (A-5): In the formula, * indicates the bonding position to other structural units or terminal groups.

In the polycarbonate resin of the second embodiment, the content of the structural units represented by formula (A-3) is preferably 70 mol% or more, more preferably 80 mol% or more, and even more preferably 90 mol% or more, of all structural units excluding terminal groups. There is no particular upper limit, and 100 mol% may be structural units represented by formula (A-3).
The polycarbonate resin may have other structural units, such as the structural unit represented by formula (A-1) and the structural unit derived from an aromatic dihydroxy compound described in paragraph 0014 of JP-A-2018-154819, the contents of which are incorporated herein by reference.

A third embodiment of the polycarbonate resin in this embodiment is a polycarbonate resin having a structural unit represented by the following formula (A-6), and representative examples include bisphenol Z polycarbonate resin and bisphenol TMC polycarbonate resin.
In formula (A-6), each ^R8 independently represents a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an alkyl group having 1 to 9 carbon atoms (preferably 1 to 3), an aryl group having 6 to 12 carbon atoms (preferably 6 to 10), an alkoxy group having 1 to 5 carbon atoms (preferably 1 to 3), an alkenyl group having 2 to 5 carbon atoms (preferably 2 or 3), or an aralkyl group having 7 to 17 carbon atoms (preferably 7 to 11). q represents an integer of 0 to 5 (preferably an integer of 0 to 3), with an integer of 1 or 3 being preferred. * in the formula represents the bonding position to other structural units or terminal groups.
Each R ⁸ is independently preferably an alkyl group having 1 to 9 carbon atoms (preferably 1 to 3 carbon atoms), more preferably a methyl group.

The structural unit represented by formula (A-6) is preferably a structural unit represented by the following formula (A-7): In the formula, * indicates the bonding position to other structural units or terminal groups.
In formula (A-7), R ⁸ has the same meaning as R ⁸ in formula (A-6), and the preferred range is also the same.
Another preferred embodiment of the structural unit represented by formula (A-6) is one in which q is 0.

In the polycarbonate resin of the third embodiment, the content of the structural units represented by formula (A-6) is preferably 70 mol% or more, more preferably 80 mol% or more, and even more preferably 90 mol% or more, of all structural units excluding terminal groups. There is no particular upper limit, and 100 mol% may be structural units represented by formula (A-6).
The polycarbonate resin may have other structural units, such as the structural unit represented by formula (A-1) above, the structural unit represented by formula (A-3) above, and a structural unit derived from an aromatic dihydroxy compound described in paragraph 0014 of JP-A No. 2018-154819, the contents of which are incorporated herein by reference.

A fourth embodiment of the polycarbonate resin in this embodiment is a polycarbonate resin having a terminal structure represented by formula (A-8).
(In formula (A-8), R ²¹ represents an alkyl group having 8 to 36 carbon atoms or an alkenyl group having 8 to 36 carbon atoms, R ²² represents a halogen atom, an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 12 carbon atoms, and n2 represents an integer of 0 to 4.)

^R21 is preferably an alkyl group or alkenyl group having 12 or more carbon atoms, and more preferably an alkyl group or alkenyl group having 14 or more carbon atoms. ^R21 is also preferably an alkyl group or alkenyl group having 22 or less carbon atoms, and more preferably an alkyl group or alkenyl group having 18 or less carbon atoms. ^R21 is preferably an alkyl group.
R ²² 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.
n2 is preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 0.

The terminal structure represented by formula (A-8) can be added to a polycarbonate resin by using a terminal terminator. For details, please refer to paragraphs 0022 to 0030 of JP 2019-2023 A, the contents of which are incorporated herein by reference.

The molecular main chain of the polycarbonate resin of the fourth embodiment is not particularly limited as long as it contains an -[O-R-OC(=O)]- unit (where R is a hydrocarbon group, specifically, an aliphatic group, an aromatic group, or one containing both an aliphatic group and an aromatic group, and further one having a linear or branched structure). The polycarbonate resin of the fourth embodiment is preferably an aromatic polycarbonate resin, more preferably a polycarbonate resin having a bisphenol skeleton, even more preferably a polycarbonate resin having a structural unit represented by the above formula (A-1), and even more preferably a bisphenol A polycarbonate resin. The use of such a polycarbonate resin achieves superior heat resistance and toughness. It is preferable that 90 mol % or more of all structural units, excluding terminal structures, have a bisphenol skeleton.

There are no particular limitations on the method for producing polycarbonate resin, and any method can be used. Examples include interfacial polymerization, melt transesterification, pyridine, ring-opening polymerization of cyclic carbonate compounds, and solid-phase transesterification of prepolymers.

The content of the amorphous thermoplastic resin (preferably polycarbonate resin) in the film of this embodiment is preferably 95% by mass or more, more preferably 97% by mass or more, and may be 99% by mass or more of the entire film. The upper limit of the content of the amorphous thermoplastic resin is the value at which the total of the amorphous thermoplastic resin and the organic particles accounts for 100% by mass of the entire film.
The film of the present embodiment may contain only one type of amorphous thermoplastic resin, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

<Organic particles>
The film of this embodiment contains organic particles having a number average particle size of 1.0 to 4.8 μm in a ratio of 0.01 to 0.45 parts by mass per 100 parts by mass of amorphous thermoplastic resin. By adopting such a configuration, it is possible to achieve slidability and windability while maintaining the high transparency inherent to amorphous thermoplastic resins.

The organic particles have a number average particle diameter of 1.0 to 4.8 μm. By setting the number average particle diameter to be equal to or greater than the lower limit, the sliding properties of the film tend to be further improved. By setting the number average particle diameter to be equal to or less than the upper limit, the transparency of the film tends to be further improved.
The number average particle size is preferably 1.8 μm or more, more preferably 2.6 μm or more. The number average particle size is preferably 4.6 μm or less, more preferably 4.4 μm or less, and even more preferably 4.0 μm or less. As the number average particle size increases, the number of organic particles contained decreases when compared with the same blending amount, resulting in an insufficient number of irregularities and poor sliding properties.
When the film of the present embodiment contains two or more types of organic particles, the number average particle size is the number average particle size of the mixture of organic particles.

Organic particles are particles that contain organic matter.
The organic particles are preferably rubber-free particles.
"Rubber-free" means, for example, that the rubber component of the particles is less than 1.0% by mass, preferably 0.5% by mass or less, more preferably 0.1% by mass or less, even more preferably 0.05% by mass or less, and even more preferably 0.01% by mass or less. Examples of rubber components include diene rubbers such as polybutadiene and acrylic rubbers such as polybutyl acrylate. By not including rubber, the hardness of the organic particles is increased, allowing appropriate irregularities to be formed on the surface of the film. On the other hand, elastomers such as butadiene styrene rubber make it difficult to impart appropriate irregularities to the surface of the film, and the desired sliding properties cannot be achieved. Note that when the film of this embodiment contains two or more types of organic particles, the amount of rubber component is the total amount of rubber component relative to the total amount of organic particles.
The organic particles preferably contain styrene. By containing styrene, the refractive index of the organic particles becomes closer to that of the polycarbonate resin, and the transparency of the obtained film can be further improved. When the organic particles contain styrene, it is sufficient that at least 50% by area of the surface layer of the organic particles is styrene.

The content of the organic particles is 0.01 to 0.45 parts by mass per 100 parts by mass of the amorphous thermoplastic resin (preferably polycarbonate resin). By setting the content at or above the lower limit, sliding properties can be achieved. On the other hand, by setting the content at or below the upper limit, the transparency of the film, particularly the haze, can be improved.
The content of the organic particles is preferably 0.02 parts by mass or more, more preferably 0.03 parts by mass or more, and even more preferably 0.04 parts by mass or more, relative to 100 parts by mass of the amorphous thermoplastic resin. The content of the organic particles is preferably 0.40 parts by mass or less, more preferably 0.30 parts by mass or less, even more preferably 0.20 parts by mass or less, even more preferably 0.12 parts by mass or less, even more preferably 0.10 parts by mass or less, and even more preferably 0.08 parts by mass or less, relative to 100 parts by mass of the amorphous thermoplastic resin.
The film of the present embodiment may contain only one type of organic particle, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

The film of this embodiment preferably contains substantially no particles other than the organic particles (e.g., inorganic particles). "Substantially no particles other than organic particles" means that the content of particles other than the organic particles is 10% by mass or less of the content of the organic particles used in this embodiment, preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 1% by mass or less, and even more preferably 0.1% by mass or less.

<Release Agent>
The film of the present embodiment preferably contains a release agent.
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 film 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 amorphous thermoplastic 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 amorphous thermoplastic resin, the film of this embodiment may contain other components within the scope of the present invention. Specifically, the film may contain antioxidants, transesterification inhibitors, 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 film of the present embodiment may be configured to be substantially free of resin components other than the amorphous thermoplastic resin (preferably resin components other than polycarbonate resin). "Substantially free" means that the content of resin components other than the amorphous thermoplastic resin is less than 1 part by mass per 100 parts by mass of the resin components contained in the film of the present embodiment.
The film of the present embodiment may be substantially free of an ultraviolet absorber. "Substantially free" means that the content of the ultraviolet absorber in the film of the present embodiment is less than 0.05 parts by mass per 100 parts by mass of the resin component.

For details of the antioxidant, please refer to paragraphs 0057 to 0061 of JP 2017-031313 A, the contents of which are incorporated herein by reference.
For details of the transesterification inhibitor, please refer to paragraphs 0035 to 0039 of WO 2015/190162, paragraph 0037 of JP-A 2019-002023, and paragraph 0041 of JP-A 2018-199745, the contents of which are incorporated herein by reference.

<Method of manufacturing resin film>
The film of this embodiment can be produced by a known production method. For example, the amorphous thermoplastic resin, organic particles, and other components that are optionally blended can be melt-kneaded and then extruded into a film. Furthermore, roll-to-roll production is preferred.

<Rolled body>
The film of this embodiment can be wound around a core material to form a roll. For example, the film of this embodiment can be wound up to 30 m or more onto a paper tube with an inner diameter of 3 inches without using a masking film by controlling the take-up tension to 200 N. In particular, the film can be made to have excellent winding properties for polycarbonate resin films with a thickness of 20 to 100 μm.

<Application>
The film of the present embodiment may be a single-layer film or a multi-layer film composed of multiple resin layers, but is preferably a single-layer film, which makes it easy to properly expose the organic particles on the film surface.
The film of this embodiment can be used as a multilayer body including the film (preferably a monolayer film) and at least one other layer. By producing a monolayer film and then laminating another layer, the surface irregularities of the film can be appropriately maintained. Known layers can be used as the other layer, such as an adhesive layer. That is, an example of a use of the film of this embodiment is a bonding adhesive sheet having the film of this embodiment and an adhesive layer. The adhesive layer preferably contains at least one of an acrylic adhesive, a silicone adhesive, and a urethane adhesive. The thickness of the adhesive layer is preferably 10 to 70 μm. For details of the adhesive layer, please refer to paragraphs 0046 to 0051 of WO 2021/029283, the contents of which are incorporated herein by reference. Furthermore, the bonding adhesive sheet preferably has a primer layer between the film of this embodiment and the adhesive layer. Such a bonding adhesive sheet is, for example, bonded to the surface of a resin molded product. For details of the adhesive lamination sheet and the primer layer, please refer to the descriptions in paragraphs 0052 to 0077 of WO 2021/029283, the contents of which are incorporated herein by reference.

The pressure-sensitive adhesive sheet for lamination of the present embodiment can be used as a constituent material for various elements such as image display devices such as mobile phone terminals, smartphones, portable electronic toys, personal digital assistants, tablet devices, mobile personal computers, and wearable terminals, as well as stationary display devices such as liquid crystal televisions, liquid crystal monitors, desktop personal computers, car navigation systems, and automobile meters. In particular, it can be suitably used as a transparent conductive film for the liquid crystal members, or as a substrate material or protective material for various elements.
The film of the present embodiment is also preferably used as a masking film, more preferably as an anti-blocking film, and also preferably used as a protective film for a transparent conductive film. In particular, it is 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 the present 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.
In addition to the above, the film of this embodiment is also preferably used as a film for applications requiring good sliding properties and clarity of projected images.

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.

1. Raw material amorphous thermoplastic resin A1: bisphenol A polycarbonate resin. An aromatic polycarbonate resin obtained by interfacial polymerization using bisphenol A as a starting material, manufactured by Mitsubishi Engineering-Plastics Corporation, S-3000F, viscosity average molecular weight: 21,000.

Organic particles B1: Eposter MA2003, acrylic-styrene particles (rubber-free), manufactured by Nippon Shokubai Co., Ltd., number average particle diameter: 1.6 μm
B2: Soliostar RA-I-35-AX, silicone-styrene particles (rubber-free), manufactured by Nippon Shokubai Co., Ltd., number average particle diameter: 3.6 μm
B3: Techpolymer SBX-4, styrene particles (rubber-free), manufactured by Sekisui Plastics Co., Ltd., number average particle diameter: 3.1 μm
B4: Chemisnow KMR-3TA, acrylic particles (rubber-free), manufactured by Soken Chemical & Engineering Co., Ltd., number average particle size: 2.4 μm
B5: Chemisnow KSR-3A, styrene particles (rubber-free), manufactured by Soken Chemical & Engineering Co., Ltd., number average particle diameter: 1.9 μm
B6: Matsumoto Microsphere M-201, acrylic particles (rubber-free), manufactured by Matsumoto Oil & Fat Co., Ltd., number average particle diameter: 2.2 μm
B7: SRB5104, manufactured by Fujikura Chemical Co., Ltd., acrylic-styrene particles (rubber-free), number average particle diameter: 0.6 μm
B8: Techpolymer SBX-17, styrene particles (rubber-free), manufactured by Sekisui Plastics Co., Ltd., number average particle diameter: 9.1 μm
B9: Optobeads 3500M, melamine particles (rubber-free), manufactured by Nissan Chemical Industries, Ltd., number average particle diameter: 2.5 μm

Release agent C1: Glycerin monostearate, Rikemal S-100A manufactured by Riken Vitamin Co., Ltd.

<Measurement of number average particle size of organic particles>
The number average particle diameter of the organic particles was measured by observing the particles at a magnification of 1000 times using a field emission scanning electron microscope and measuring the particle diameter from the photograph. The number average value of the measured values of 100 randomly selected particles was taken as the number average particle diameter (unit: μm). When the particles in the micrograph were not circular, the particle diameter was calculated by converting the particle diameter into a circle of the same area.
The field emission scanning electron microscope used was "SU8220" manufactured by Hitachi High-Technologies Corporation.

2. Examples 1 to 6 and Comparative Examples 1 to 5
<Pellet production>
Each of the components described above was weighed out so as to obtain the amount added shown in Table 1 or Table 2. Each component in Table 1 or Table 2 is shown in parts by mass. The mixture was then mixed in a tumbler for 10 minutes, and then melt-kneaded at a cylinder temperature of 260°C using a vented twin-screw extruder with a screw diameter of 32 mm ("TEX30α" manufactured by The Japan Steel Works, Ltd.), and pellets were obtained by strand cutting.

<Film production>
The resulting pellets were used to produce a film in the following manner.
The pellets obtained above were extruded into a molten state using a T-die melt extruder consisting of a vented twin-screw extruder (manufactured by The 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 then cooled and solidified by a second roll to produce a film. The cylinder temperature and die head temperature were 260°C.
The final film thickness was adjusted by changing the roll speed of the second roll so as to obtain the value shown in Table 1 or Table 2.

Details of the second roll used are as follows.
Second roll: Metal rigid roll (surface: hard chrome treated), manufactured by JSW Corporation
Core diameter: outer diameter 250 mm x width 600 mm
Roll temperature: 140°C

<Measurement of total light transmittance and haze>
The total light transmittance (unit: %) and haze (unit: %) of the obtained film were measured under the 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 Co., Ltd.) was used.

<Measurement of Spd and S10z>
The uneven surface of the obtained film was measured for S5p, S5v, and Spd as specified in ISO 25718-2:2012 using a scanning white light interference microscope VS1550 manufactured by Hitachi High-Tech Science Corporation. The S10z value was calculated from the measured values of S5p and S5v. S10z is the sum of S5p and S5v. Measurement and analysis were performed at three arbitrary locations, and the average value was adopted. The unit of S5p is μm, the unit of S5v is μm, and the unit of Spd is the number per 1 ^mm2 (unit: pieces/ ^mm2 ).
The measurement conditions were as follows:
Field of view: Single field of view measurement CCD camera: 1/3 inch Objective lens: x5
Observation area: 935.267 × 701.502 μm ²
Field of view size: 640 x 480 pixels
Measurement mode: wave mode Wavelength filter: 530 nm White
Observation conditions Interpolation conditions: Fully interpolated Surface correction conditions: Fourth-order polynomial approximation

<Measurement of dynamic friction coefficient>
The dynamic coefficient of friction of the film was measured as the dynamic coefficient of friction against a film with a root mean square roughness of 0.093 μm.
A film having a root mean square roughness of 0.093 μm and the film obtained above were placed so as to overlap each other, and the obtained film was slid over the film having a root mean square roughness of 0.093 μm under conditions of a thread speed of 100 mm/min and a load cell of 10 N, to measure the dynamic friction coefficient.
The friction coefficient measuring device used was a "Friction Tester" manufactured by Toyo Seiki Seisakusho, Ltd.
The film used for the root mean square roughness of 0.093 μm was a bisphenol A polycarbonate resin film with a masking film on one side (FE-2000, 100 μm thick, manufactured by Mitsubishi Gas Chemical Company, Inc.). In this example, the bisphenol A polycarbonate resin film with a masking film on one side was placed with the unmasked side facing up, and was fixed to the right edge of the test table with tape so that its long axis coincided with the long axis of the test table. The resulting film was attached to the underside of a 63 mm x 63 mm, 200 g sled, and the polycarbonate resin film and the resulting film were placed so as to overlap. The resulting film was then slid as described above to measure the coefficient of dynamic friction.
In Table 1 or Table 2, "x" means that measurement was not possible. In Comparative Example 2, the particle size of the organic particles was small and the unevenness exposed on the surface was small, and in Comparative Example 5, the film was too thick to form unevenness of sufficient size on the surface, so the films stuck together and the dynamic friction coefficient could not be measured.

<Measurement of root mean square roughness Rq>
The surface roughness of the film used to measure the coefficient of dynamic friction, which had a root mean square roughness of 0.093 μm, was measured using a surface roughness measuring device.
The detector of the measuring instrument was set to an "integrated type," and a "standard drive unit" was attached to the detector's drive section. The film was fixed to a glass plate with tape, and the surface roughness measuring instrument was placed on top of it so that it would not move. Measurements were then carried out under the measurement conditions of the standard "JIS B 0601-2001," with a measurement speed of 0.5 mm/s, a cutoff value of 0.8, and three sections, and the root mean square roughness Rq was measured. The root mean square roughness Rq was measured three times at different locations on the film, and the average value was calculated.
The measuring instrument used was "SJ-210" manufactured by Mitutoyo Corporation.

<Evaluation of the roll shape>
In the production of the above film, the speed of the second roll was adjusted so that the film would have a predetermined thickness, and the take-up tension of the film winding machine was controlled to 200 N. The film was wound up 30 m onto a paper tube with an inner diameter of 3 inches without using a masking film, and the appearance of the film was evaluated. Five experts evaluated the film and a majority vote was used.
A: No wrinkles were generated and the film could be wound up with a good appearance.
B: Other than A and C above, for example, although winding was possible, sticking occurred and wrinkles occurred during winding.
C: It was not possible to wind the film around the paper tube.

<Projection evaluation>
A projected image of the resulting film was obtained by illuminating it with a high-intensity light source.
Specifically, a white paper was attached to the wall, a high-brightness light source was placed 120 cm away from the white paper, and a film placed halfway between the wall and the light source, i.e., 60 cm from the wall, was illuminated with light, resulting in a projected image of the film onto the white paper attached to the wall.
As a high-intensity light source, "S-Light" manufactured by Nippon Gijutsu Center Co., Ltd. was used.
A: The image is clearly visible.
B: The image is blurred.

The amounts of each of the above components are in parts by mass.

3. Production of a film with an adhesive layer In Example 4 of WO 2021/029283, the substrate sheet 1 was changed to the film described in Example 4 above, and the rest was carried out in the same manner to obtain an adhesive sheet. The adhesive layer at this time was laminated on the contact surface of the second roll. The obtained adhesive sheet was bonded to a bisphenol A polycarbonate resin film (manufactured by Mitsubishi Gas Chemical Company, Inc., FE-2000, thickness 100 μm) with a root mean square roughness of 0.093 μm, and it was confirmed that no bubbles or the like were generated and the appearance was good.

10 Transparent conductive film 11 Electrode layer (transparent conductive film)
12 Base material 13 Adhesive layer 14 Protective film 21 Polycarbonate resin film with a smooth surface 22 Polycarbonate resin film with fine irregularities on the surface

Claims (11)

For 100 parts by mass of amorphous thermoplastic resin,
A film containing 0.01 to 0.45 parts by mass of organic particles having a number average particle diameter of 1.0 to 4.8 μm,
The film surface has an Spd of 65 to 400 particles and an S10z of 0.40 to 2.50 μm,
Spd indicates the number of convex portions per 1 ^mm2 of the film (unit: pieces),
S10z represents the sum of S5p and S5v,
S5p indicates the average value (unit: μm) of the local heights of the first five peaks in order from the highest peak, S5v indicates the average value (unit: μm) of the local depths of the first five valleys in order from the deepest valley, S5p, S5v, and Spd are values specified in ISO25718-2:2012,
A film having a thickness of 20 μm or more and less than 300 μm. The film described in claim 1, wherein the total light transmittance of the film under conditions of a D65 light source and a 10° field of view is 86.0% or more. The film described in claim 1 or 2, wherein the haze of the film under conditions of a D65 light source and a 10° field of view is less than 2.0%. The film described in any one of claims 1 to 3, wherein the number average particle diameter of the organic particles is 2.6 to 4.8 μm. The film described in any one of claims 1 to 4, wherein the content of the organic particles is 0.01 to 0.40 parts by mass per 100 parts by mass of the amorphous thermoplastic resin. The film described in any one of claims 1 to 5, wherein the organic particles are non-rubber-containing particles. The film described in any one of claims 1 to 6, wherein at least one surface of the film has a dynamic friction coefficient of 1.00 or less against a film having a root-mean-square roughness of 0.093 μm. The film described in any one of claims 1 to 7 is a single-layer film. A multilayer body comprising the film according to any one of claims 1 to 8 and at least one other layer. The multilayer body according to claim 9, wherein the other layer includes an adhesive layer. A protective layer;
An adhesive layer;
A substrate;
a transparent conductive film having, in this order, a first electrode layer and a second electrode layer,
A transparent conductive film, wherein at least one of the substrate and the protective layer is the film according to any one of claims 1 to 8.