KR102680427B1 - film - Google Patents

Abstract

(Problem) To provide a film capable of improving applicability, peelability after processing, and the characteristics and quality of the functional film when used as a process substrate for obtaining a thin film of a functional material layer (functional film) by applying a functional material. The purpose is to
(Solution) A film having a polymer A layer on at least one side, wherein the maximum height of the polymer A layer determined by AFM is Rm1 (nm), and the maximum height of the polymer A layer determined by AFM after heat treatment at 180°C for 5 minutes is Rm2. A film characterized by satisfying the following formula (I) when expressed in terms of (nm).
Rm2-Rm1 > 0nm···(I)

Description

film

The present invention relates to films for manufacturing processes.

Thermoplastic resin films are widely used in optical applications, packaging applications, and industrial material applications, depending on their various properties. In addition, in industrial material applications, thermoplastic resin films are used as process substrates for manufacturing semiconductor thin films and circuit members, for example, films for the back side of semiconductors (for example, patent document 1), which are used when manufacturing semiconductors. , a release film (for example, patent document 2) used when forming a circuit member has been proposed.

In the case of a film as shown in Patent Document 1, the heat-expandable microspheres expand by heating and change the surface shape of the film to improve the pick-up properties of the semiconductor. However, since the change in surface shape is large, the process of applying a coating material that is more flexible than that of the semiconductor is required. When used as a base material, changes in surface shape may be transferred to the coating material, resulting in insufficient smoothness of the resulting coating material, or it may be difficult to obtain the desired peelability due to the anchor effect. Additionally, since the adhesive layer is disposed on the outermost surface of the film, there are cases where the film itself is easily damaged or foreign substances are easily attached.

In the case of a film as shown in Patent Document 2, it has a mat-shaped surface design, and when used as a process substrate, the smoothness of the coating material obtained may be insufficient, or it may be difficult to obtain the desired peelability depending on the coating material. there was.

Japanese Patent Publication No. 2012-033636 Japanese Patent Publication No. 2016-043594

In the present invention, the above-described drawbacks are overcome, and when used as a process substrate for applying a functional material to obtain a thin film of a functional material layer (functional film), the applicability, peelability after processing, and the characteristics and quality of the functional film are improved. The purpose is to provide a film that can be used.

The first film of the present invention for solving the above problems has the following structure.

(1) A film having a polymer A layer on at least one side, wherein the maximum height of the polymer A layer determined by AFM is Rm1 (nm), and the maximum height of the polymer A layer determined by AFM after heat treatment at 180°C for 5 minutes is Rm2 ( A film characterized by satisfying the following formula (I) when expressed as nm).

Rm2-Rm1 > 0nm···(I)

(2) The film according to (1) that satisfies the following formula (II).

1nm ≤ (Rm2-Rm1) ≤ 2.0×10 ⁴ nm···(II)

(3) The film according to (1) or (2) that satisfies the following formula (III) when the arithmetic mean roughness of the polymer A layer determined by AFM after heat treatment at 180°C for 5 minutes is Ra2 (nm).

6 ≤ (Rm2/Ra2) ≤15···(III)

(4) The film according to any one of (1) to (3) that satisfies the following formula (IV).

(Rm2/Ra2) - (Rm1/Ra1) > 0···(IV)

(5) The film according to any one of (1) to (4), wherein the main component of the polymer A layer is a polyester resin.

(6) The film according to any one of (1) to (5), wherein the polymer A layer after heat treatment at 180°C for 5 minutes has a glossiness (60°) of 30 or more.

(7) The film according to any one of (1) to (6), wherein the polymer A layer has an indentation elastic modulus of 800 N/mm 2 or more and 6,000 N/mm 2 or less.

(8) The film according to any one of (1) to (7), wherein the film has a tear propagation resistance of 4.0 N/mm or more and 12.0 N/mm or less in the main orientation axis direction and the direction perpendicular to the main orientation axis.

(9) The film according to any one of (1) to (8) used for manufacturing process purposes.

The second film of the present invention for solving the above problems has the following structure. That is, it is a film having a polymer A layer on at least one side, and the surface free energy of the polymer A layer is SE1 (mN/m), and the surface free energy of the polymer A layer after heat treatment at 180°C for 5 minutes is SE2 (mN/m). ), it is a film characterized by satisfying the following formula (I).

SE1-SE2 > 0mN/m···(a)

Since the first and second films of the present invention can have good adhesion before heating and good peelability after heating, when used as a process substrate for obtaining a thin film of a functional material (functional film) by applying a functional material, the functional material can be obtained. It has the effect of improving the properties and quality of the membrane.

Hereinafter, the film of the present invention will be described in detail.

[First film]

The first film of the present invention is a film having a polymer A layer on at least one side, and the maximum height of the polymer A layer determined by AFM is Rm1 (nm), and the maximum height of the polymer A layer determined by AFM after heat treatment at 180°C for 5 minutes is Rm1 (nm). When the height is Rm2 (nm), it is important to satisfy the following equation (I).

Rm2-Rm1 > 0nm···(I)

Here, Rm1 (nm) is taken as the value obtained as follows. In an AFM (atomic force microscope) such as "Nano ScopeV Dimension Icon" manufactured by Bruker AXS, a silicon cantilever is applied as a probe, the surface shape of the film is measured in tapping mode, and then the software attached to the AFM (e.g. For example, Nano Scope Analysis, etc.), the maximum height was calculated under the condition of a cutoff of 3 nm. Repeat this measurement 5 times and take the average of the 5 measurements. In addition, the measurement direction (scanning direction of the probe) is measured in one direction and two directions perpendicular to the direction, and the average value of the maximum height in each direction (i.e., the five measurements in one direction and the average of the maximum height in each direction is measured) , the average value of 10 measurements (a total of 5 measurements in a direction orthogonal to any one direction) is adopted as Rm1 (nm).

Additionally, for Rm2 (nm), the maximum height is calculated 5 times in the same manner as Rm1 (nm) for a film subjected to heat treatment at 180°C for 5 minutes, and the average value of the 5 measurements is obtained. In addition, the measurement direction (scanning direction of the probe) is measured in one direction and two directions perpendicular to the direction perpendicular to the direction, and the average value of the maximum height in each direction (i.e., the five measurements in one direction and , the average value of 10 measurements (a total of 5 measurements in a direction orthogonal to any one direction) is adopted as Rm2 (nm).

Heat treatment at 180°C for 5 minutes in the present invention is a treatment that imitates the heating of the film that occurs for drying the functional film and improving functionality when using the film as a process substrate for the functional film, for example, set to 180°C. This refers to a process in which the film is conveyed in a conveyor oven with hot air circulation over a period of 5 minutes. Additionally, when conveying the film, the film is sandwiched between two metal frames and the metal frames are fixed with metal clips to prevent the film from directly contacting the conveyor.

In the present invention, formula (I) indicates that the maximum height of the polymer A layer determined by AFM increases after heat treatment at 180°C for 5 minutes. In addition, the maximum height obtained under these conditions, such as Rm1 (nm) and Rm2 (nm), has a very narrow measurement range, unlike measurement with a general contact-type 3D roughness meter, such as known sand mat processed films and embossed films. , It is a value that is less susceptible to the influence of unevenness of the mat film due to kneading particles. By increasing the maximum height in the microscopic range determined by AFM after heating, for example, when the film of the present invention is laminated with a functional film, a microscopic amount is formed at the interface between the film and the functional film without significantly changing the smoothness of the functional film. By forming a space, it becomes possible to reduce adhesion to the functional film. That is, it was discovered that the film of the present invention can achieve both adhesion to the functional film before heating and peelability from the functional film after heating by increasing the maximum height in the microscopic range determined by AFM after heating.

As a method for keeping Rm1 (nm) and Rm2 (nm) in the range of formula (I), the polymer A layer is composed of a combination of two or more types of polymers, and after stretching the polymer A layer, the polymer A layer is incorporated into the polymer A layer. Among the polymers available, only low-melting point polymers are deformed by heating at 180°C for 5 minutes to form deformation on the surface of the polymer A layer. The polymer A layer is composed of a crystalline polymer, and the polymer is subjected to UV treatment, plasma treatment, etc. A method of forming strain on the surface of layer A by forming microcrystals in layer A and subjecting only the amorphous portion around the crystallites to thermal movement by heating at 180°C for 5 minutes. Microscopic voids are formed in the polymer layer A and heated at 180°C for 5 minutes. Examples include a method of softening the polymer around the pores by heating to change the shape of the pores, thereby forming strain on the surface of the polymer A layer. In addition, when using a method of forming strain on the surface of the polymer A layer by stretching the polymer A layer and then deforming only the low melting point polymer among the polymers included in the polymer A layer by heating at 180°C for 5 minutes, the low melting point polymer is Stretching at a temperature 20°C or more and 100°C or less higher than the polymer melting point is preferably used because it balances the domain mobility of the low melting point polymer and strain accumulation for movement.

When the first film of the present invention is used as a process substrate for producing a functional film, it is preferable to satisfy the following formula (II) from the viewpoint of improving the smoothness of the functional film and the peelability after heating.

1nm ≤ (Rm2-Rm1) ≤ 2.0×10 ⁴ nm···(II)

The first film of the present invention has good peelability after heating by setting (Rm2-Rm1) to 1 nm or more. (Rm2-Rm1) is more preferably 3 nm or more from the viewpoint of improving peelability after heating. Additionally, by setting (Rm2-Rm1) to 2.0 x 10 ⁴ nm or less, the smoothness of the functional film and the function associated with the smoothness become good. (Rm2-Rm1) is more preferably 1.0 × 10 ³ nm or less, more preferably 100 nm or less, particularly preferably 50 nm or less, from the viewpoint of improving the smoothness of the functional film and the function due to the smoothness. is most desirable.

As a method for keeping (Rm2-Rm1) in the range of formula (II), the polymer A layer is composed of a combination of two or more types of polymers, the polymer A layer is stretched, and then the lowest polymer contained in the polymer A layer is added. In the method of forming strain on the surface of the polymer A layer by deforming only the melting point polymer by heating at 180°C for 5 minutes, a method of feeding a low melting point polymer among the polymers contained in the polymer A layer into an extruder by a side feed method is included. You can. By injecting only the low-melting point polymer through the side feed method, the low-melting point polymer is extruded at a temperature much higher than the melting point (e.g., an extrusion temperature suitable for the polymer contained in the polymer A layer and whose main component has a high melting point), and the melt viscosity increases. It becomes possible to suppress the decrease in dispersibility with the polymer, which is the main component of the polymer A layer. As another method, the polymer A layer is composed of a crystalline polymer, microcrystals are formed in the polymer A layer by UV treatment or plasma treatment, and only the amorphous portion around the crystallites is heated at 180°C for 5 minutes. In the method of forming strain on the surface of the polymer A layer by exercising it, a method of adjusting the surface treatment conditions such as UV treatment or plasma treatment and the concentration of the crystalline polymer in the polymer A layer, forming microscopic voids in the polymer A layer , a method of softening the polymer around the pores by heating at 180°C for 5 minutes to change the shape of the pores, thereby forming strain on the surface of the polymer A layer, and a method of setting the size of the pores to a specific range. .

The first film of the present invention has the smoothness of the functional film when used as a process substrate for manufacturing a functional film, when the arithmetic mean roughness of the polymer A layer determined by AFM after heat treatment at 180°C for 5 minutes is Ra2 (nm). , it is preferable to satisfy the following formula (III) from the viewpoint of improving peelability after heating.

6 ≤ (Rm2/Ra2) ≤ 15···(III)

Here, Ra2 (nm) is taken as the value obtained as follows. In an AFM (atomic force microscope) such as "Nano ScopeV Dimension Icon" manufactured by Bruker AXS, a silicon cantilever is applied as a probe, and the surface shape of a film subjected to heat treatment at 180°C for 5 minutes in tapping mode is measured. Using software attached to AFM (e.g. Nano Scope Analysis, etc.), the arithmetic mean illuminance was calculated under the condition of a cutoff of 3 nm. Repeat this measurement 5 times and take the average of the 5 measurements. In addition, the measurement direction (scanning direction of the probe) is measured in an arbitrary direction and in two directions perpendicular to the arbitrary direction, and the average value of the arithmetic mean illuminance in each direction (i.e., 5 times in an arbitrary direction) is measured. The measured value and the average value of 10 measurements (a total of 5 measurements in a direction perpendicular to any one direction) are adopted as Ra2 (nm). (Rm2/Ra2) is the maximum height in the polymer A layer by AFM after heat treatment at 180°C for 5 minutes divided by the arithmetic average roughness by AFM after heat treatment at 180°C for 5 minutes. (Rm2/Ra2) is small. The maximum height relative to the arithmetic average roughness in AFM is small, that is, the difference between the maximum height of the uneven peak height obtained by AFM and the heights of other peaks tends to be small. Additionally, the larger (Rm2/Ra2), the larger the maximum height relative to the arithmetic mean roughness in AFM, that is, the difference between the maximum height of the uneven peak height obtained by AFM and the heights of other peaks tends to be large. When applying a film as a process substrate for manufacturing a functional film, if (Rm2/Ra2) is too small, acids other than the acid with the maximum height may be lowered overall, and peelability from the functional film after heating may be insufficient. , (Rm2/Ra2) is too large, the overall acidity other than the acid with the maximum height may become high, and the smoothness of the functional film may become insufficient. Therefore, in the film of the present invention, by setting (Rm2/Ra2) in the range of formula (III), it becomes possible to achieve both the smoothness of the functional film and the peelability after heating in a high range. Furthermore, (Rm2/Ra2) is a value that appears to be correlated with the surface shape of the functional film, and in applications where functional films are stacked (for example, in circuit member applications such as chip multilayer ceramic capacitors or chip inductors), Rm2 By setting (Rm2/Ra2), rather than (nm) or Ra2 (nm), to the range of equation (III), the voids in the laminated portion when the functional membranes are laminated can be set to an appropriate range, and the functional membranes can be formed into a laminate. Various characteristics (e.g., miniaturization during lamination, low profile, etc.) can also be improved. From the viewpoint of achieving both the peelability and smoothness of the functional film, (Rm2/Ra2) of the film of the present invention is more preferably 7 or more and 14 or less, and especially preferably 8 or more and 12 or less.

As a method for keeping (Rm2/Ra2) in the desired range, the polymer A layer is composed of a combination of two or more types of polymers, the polymer A layer is stretched, and then only the low melting point polymer is added from among the polymers contained in the polymer A layer. In the method of forming strain on the surface of the polymer A layer by heating at 180°C for 5 minutes, the concentration of the low melting point polymer for the entire polymer A layer and the thickness of the polymer A layer are adjusted to a specific range, Polymer A The layer is composed of a crystalline polymer, microcrystals are formed in the polymer A layer by UV treatment or plasma treatment, and only the amorphous portion around the crystallites is thermally moved by heating at 180°C for 5 minutes to form a crystallite on the surface of the polymer A layer. In the method of forming the strain, the surface treatment conditions such as UV treatment or plasma treatment and the concentration of the crystalline polymer in the polymer A layer are adjusted, a microscopic void is formed in the polymer A layer, and heating is performed at 180°C for 5 minutes. In the method of softening the polymer around the pores to change the shape of the pores and forming strain on the surface of the polymer A layer, a method of setting the size of the pores to a specific range is included.

When the first film of the present invention is used as a process substrate for manufacturing a functional film when the arithmetic mean roughness of the polymer A layer determined by AFM is Ra1 (nm), from the viewpoint of improving peelability after heating, It is preferable that the following formula (IV) is satisfied.

(Rm2/Ra2) - (Rm1/Ra1) > 0···(IV)

Here, Ra1 (nm) is taken as the value obtained as follows. In an AFM (atomic force microscope) such as "Nano ScopeV Dimension Icon" manufactured by Bruker AXS, a silicon cantilever is applied as a probe, the surface shape of the film is measured in tapping mode, and then the software attached to the AFM (e.g. For example, Nano Scope Analysis, etc.), the arithmetic average roughness was calculated under the condition of a cutoff of 3 nm. Repeat this measurement 5 times and take the average of the 5 measurements. In addition, the measurement direction (scanning direction of the probe) is measured in one direction and two directions perpendicular to the direction perpendicular to the direction, and the average value of the arithmetic mean illuminance in each direction is taken as Ra1 (nm). By increasing the value (Rm2/Ra2), which is the value after treatment at 180°C for 5 minutes, compared to (Rm1/Ra1), which is the value before heating the film, the height of the acid other than the maximum height after heating increases, or the maximum height after heating increases. Since the acid content is low, interlayer strain between the polymer A layer and the functional film can be easily formed, and peelability after heating can be improved.

For (Rm1/Ra1) and (Rm2/Ra2), a method to satisfy the relationship of equation (IV) is to make the polymer A layer into a composition of two or more types of polymers, stretch the polymer A layer, and then stretch the polymer A layer. In the method of forming strain on the surface of A layer by deforming only the low melting point polymer among the polymers contained in the A layer by heating at 180°C for 5 minutes, the type and concentration of the low melting point polymer are used as specific components, polymer A layer It is composed of a crystalline polymer, microcrystals are formed in the polymer A layer by UV treatment or plasma treatment, and only the amorphous portion around the crystallites is subjected to thermal movement by heating at 180°C for 5 minutes to deform the surface of the polymer A layer. In the method of forming, a method of adjusting surface treatment conditions such as UV treatment or plasma treatment and the concentration of crystalline polymer in the polymer A layer, forming microscopic voids in the polymer A layer, and heating at 180°C for 5 minutes A method of softening the polymer around the pores to change the shape of the pores to create strain on the surface of the polymer A layer includes a method of setting the size of the pores to a specific range.

[Second Film]

The second film of the present invention is a film having a polymer A layer on at least one side, and the surface free energy of the polymer A layer is SE1 (mN/m), and the surface free energy of the polymer A layer after heat treatment at 180°C for 5 minutes is When SE2 (mN/m), it is important to satisfy the following equation (a).

SE1-SE2 > 0mN/m···(a)

Here, SE1 (mN/m) and SE2 (mN/m) are taken as the values obtained as follows. A contact angle meter (CA-D type, manufactured by Kyowa Interface Science, Inc.) was used for a film that had been subjected to humidity control for 24 hours under conditions of 23°C and 65%RH, and was measured using water, ethylene glycol, formamide, and methylene iodide. Using various measuring liquids, the static contact angle with respect to the film surface was determined using a contact angle meter CA-D type manufactured by Kyowa Interface Science, Inc. The contact angle obtained for each liquid and each component of the surface tension of the measured liquid were respectively substituted into the equations below, and a simultaneous equation consisting of four equations was solved for γ ^L , γ ⁺ , and γ ^- .

However, γ=γ ^L + 2(γ ⁺ γ ^- ) ^{1/ 2} γ _j = γ _j ^L + 2(γ _j ⁺ γ _j ^- ) ^1/2 Here, γ, γ ^L , γ ⁺ , γ ^- are γ _j , γ _j ^L , γ j + , and γ j - are the surface free energy of the film surface, long-range force term, Lewis acid parameter, and Lewis base parameter, respectively, and γ j , γ j L , γ _j ⁺ , and γ _j ^- are the surface free energy and long-range force term of the measurement liquid used, respectively. It is taken to mean Lewis acid parameter and Lewis base parameter.

The surface tension of each liquid used here was the value in Table 7 suggested by Oss ("Fundamentals of Adhesion", L. H. Lee (Ed.), p.153, Plenumess, New York (1991)).

Heat treatment at 180°C for 5 minutes in the present invention is a treatment that imitates the heating of the film that occurs for drying the functional film and improving functionality when using the film as a process substrate for the functional film, for example, set to 180°C. This refers to a process in which the film is conveyed in a conveyor oven with hot air circulation over a period of 5 minutes. Additionally, when conveying the film, the film is sandwiched between two metal frames and the metal frames are secured with metal clips to prevent the film from directly contacting the conveyor.

In the present invention, equation (a) indicates that the surface free energy of the polymer A layer decreases after heat treatment at 180°C for 5 minutes. By reducing the surface free energy of the polymer A layer after heating, for example, in the case where the film of the present invention is laminated with a functional film, adhesion when manufacturing the functional film and peeling of the functional film after heating by drying, etc. I discovered something that makes gender compatible.

As a method for making SE1-SE2 in the range of formula (a), a small amount of polymer containing a hydrophobic part is contained in the polymer A layer, and the polymer containing the hydrophobic part is placed on the island side of the polymer A layer. , a method of arranging hydrophobic portions on the film surface after heating, etc. Additionally, the sea-island structure of the polymer A layer can be confirmed by dyeing the film using a known method and then performing cross-sectional TEM observation.

When the second film of the present invention is used as a process substrate for producing a functional film, it is preferable to satisfy the following formula (b) from the viewpoint of improving the smoothness of the functional film and the peelability after heating.

0.5mN/m ≤（SE1-SE2) ≤ 40mN/m···(b)

By setting (SE1-SE2) to 0.5 mN/m or more, the film of the present invention has excellent peelability after heating. (SE1-SE2) is more preferably 2 mN/m, and particularly preferably 5 mN/m or more from the viewpoint of improving peelability after heating. In addition, by setting (SE1-SE2) to 40 mN/m or less, the peelability after heating becomes higher than necessary, thereby preventing peeling and lifting from the functional film during processing. (SE1-SE2) is more preferably 30 mN/m or less from the viewpoint of improving the peelability of the functional film and suppressing the occurrence of peeling and lifting during processing.

As a method for bringing (SE1-SE2) into the range of equation (b), a small amount of a polymer containing a hydrophobic part is contained in the polymer A layer, and the polymer containing a hydrophobic part is placed on the island side of the sea-island structure of the polymer A layer. In the method of arranging the hydrophobic portion on the film surface after heating, the weight ratio of the polymer including the hydrophobic portion to the polymer A layer, the method of adjusting the ratio of the hydrophobic portion of the polymer including the hydrophobic portion, etc. You can. Furthermore, if various surface treatments such as corona treatment are performed before heating, the hydrophobic portion is drawn to the surface, so the surface free energy is likely to decrease after heating. Therefore, various surface treatments (corona treatment, plasma treatment, UV treatment, etc.) originally used to make the film hydrophilic are also effective as a method for hydrophobizing the polymer A layer after heating and bringing it into the range of formula (b).

It is preferable that the film of the present invention satisfies the following formula (c) from the viewpoint of the applicability of the functional film and the adhesion of the functional film after heating.

25mN/m ≤ SE1 ≤ 70mN/m···(c)

SE1 is the surface free energy of the polymer A layer before heating, and is preferably 25 mN/m or more because the applicability of the functional film to the polymer A layer becomes good, more preferably 35 mN/m or more, and particularly preferably 42 mN/m. m or more. Furthermore, considering the peelability of the polymer A layer and the functional film after heating, SE1 is preferably 70 mN/m or less even before heating, and more preferably 48 mN/m or less.

Methods for adjusting SE1 to the desired range include methods of adjusting the composition of the polymer A layer and various surface treatments. It is preferable from the viewpoint of the homogeneity of the functional film that the second film of the present invention satisfies the relationship of the following equation (d), assuming that the dispersion power of the polymer A layer after heat treatment at 180°C for 5 minutes is Sd2 and the polarity power is Sp2. do.

23mN/m ≤（Sd2-Sp2) ≤ 36mN/m···(d)

Here, (Sd2-Sp2) is a value related to the polarity of the surface free energy. The smaller (Sd2-Sp2) is, the higher the polarity of the polymer A layer is, and the larger (Sd2-Sp2) is, the lower the polarity of the polymer A layer is. It represents losing. The second film of the present invention lowers the polarity of the polymer A layer after heating, thereby preventing the polar portion of the functional material from approaching the polar portion of the polymer A layer when applying the functional material, thereby preventing the dispersibility of the functional film from becoming non-uniform. and can improve various functions of the functional membrane. Additionally, (Sd2-Sp2) can be calculated from the difference between Sd2 (mN/m) and Sp2 (mN/m), respectively, by the method of the examples described later. (Sd2-Sp2) is more preferably 17 mN/m or more and 27 mN/m or less from the viewpoint of improving the function of the functional film. Methods for bringing (Sd2-Sp2) into the range of formula (d) include methods of adjusting the composition of the polymer A layer and various surface treatments. Specifically, the intrinsic viscosity of the polymer containing the hydrophobic portion contained in the polymer A layer is lowered by 0.5 or more than the intrinsic viscosity of the polymer that is the main component of the polymer A layer, and the hydrophobic component is made so that the hydrophobic component can easily be visualized on the film surface after heating. The mobility of the polymer containing the part is kept relatively high, and the heat treatment temperature after stretching during film formation is set as high as possible within a range that does not exceed the melting point of the polymer A layer, and corona treatment, UV treatment, etc. Various surface treatments are performed under very mild conditions compared to the conditions for improving the hygroscopicity of conventional films, and methods of imparting kinetic energy to polymers containing hydrophobic portions within a range that does not impair adhesion to various functional films are included. You can.

[First and Second Films]

In the first and second films of the present invention, the resin constituting the polymer A layer is not particularly limited in the range that satisfies the various requirements of the present invention, but includes, for example, polypropylene-based resin, polyethylene-based resin, and cyclic resin. Polyolefin-based resins such as olefin-based resins, modified polyolefin-based resins having side chains such as carboxylic acid or maleic anhydride (including structures substituted with metal ions) in polyolefin-based resins, polyethylene terephthalate, and polytetramethylene terephthalate. , polybutylene terephthalate, and polyester resins copolymerized with glycol components other than ethylene glycol, tetramethylene glycol, butanediol, or carboxylic acid components other than terephthalic acid, acrylic resins, polyvinylidene fluoride, and polytetrafluoride. Roethylene, tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene/hexafluoropropylene copolymer, tetrafluoroethylene/ethylene copolymer, polychlorotrifluoroethylene, chlorotrifluoroethylene · Fluorine-based resin made of ethylene copolymer, polycarbonate-based resin, polyurethane-based resin, polyvinyl chloride-based resin, polystyrene-based resin, ABS (acrylonitrile-butadiene-styrene copolymer)-based resin, AS (acrylonitrile-styrene) and copolymer)-based resins.

Among these, it is preferable that the main component of the polymer A layer is a polyester resin from the viewpoint of not causing significant deformation when heated at 180°C and from the viewpoint of cost.

The polyester resin in the present invention refers to a polymer in which a dicarboxylic acid-derived structural unit (dicarboxylic acid component) and a diol-derived structural unit (diol component) are bonded by an ester bond.

Examples of dicarboxylic acid components include terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalene dicarboxylic acid, 1,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, and 4,4-naphthalene dicarboxylic acid. Aromatic dicarboxylic acids such as '-diphenyl dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 4,4'-diphenyl sulfone dicarboxylic acid, adipic acid, suberic acid, Examples include aliphatic dicarboxylic acids such as sebacic acid, dimer acid, dodecanedioic acid, and cyclohexane dicarboxylic acid, and various aromatic dicarboxylic acids and ester derivatives of aliphatic dicarboxylic acids. These diol components may be one type other than ethylene glycol, or two or more types may be used together.

Additionally, diol components include ethylene glycol, 1,2-propanediol, 1,3-propanediol, neopentyl glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexane. Diol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, 2,2-bis (4- Hydroxyethoxyphenyl)propane, isosorbide, spiroglycol, etc. can be mentioned. These dicarboxylic acid components may be one type other than ethylene glycol, or two or more types may be used in combination.

Among these dicarboxylic acid components and diol components, from the viewpoint of solvent resistance and heat resistance, terephthalic acid, isophthalic acid, and 2,6-naphthalene dicarboxylic acid are preferable as dicarboxylic acid components, and ethylene glycol and 1,4-naphthalene dicarboxylic acid are preferable as diol components. -Butanediol, 1,4-cyclohexanedimethanol, isosorbide, and spiroglycol are preferably used.

[First film]

The polymer A layer of the first film of the present invention preferably contains one or more types of polymers different from the polymer as the main component from the viewpoint of increasing the maximum height of the polymer A layer determined by AFM after heating. From the viewpoint of forming strain at the interface between the polymer A layer and the functional film by heating and moving the portions that are less compatible with the polymer as the main component and the other polymers, the portions that are highly compatible with the polymer as the main component and the portions with lower compatibility are separated. A polymer having both configurations is preferably selected. In addition, the polymer that is different from the main component polymer is used to increase the difference in orientation relaxation with the polymer that is the main component of the polymer A layer when heated, so that it is easier to form strain at the interface between the polymer A layer and the functional film, compared to the polymer that is the main component. A low melting point is desirable. The melting point of the polymer different from the main component polymer is preferably at least 15°C lower than that of the main component polymer, and more preferably at least 30°C lower. In addition, the polymer as the main component may be an amorphous polymer that does not have a melting point, but in the case of an amorphous polymer, the content of 20% by mass or less based on 100% by mass of the polymer A layer is used to prevent deformation of the film even when heated at 180°C. Concentration is preferred. In addition, as a polymer that is different from the polymer that is the main component, minute voids are formed in the polymer A layer, and the shape of the void is changed after heating to form strain at the interface between the polymer A layer and the functional film. A polymer with low compatibility with the phosphorus polymer and a polymer with a close melt viscosity is preferably selected.

As an example of the polymer A layer of the first film of the present invention, the main component is a polyester resin, and in the case of polyethylene terephthalate among the polyester resins, it has both a portion with high compatibility with the polymer as the main component and a portion with low compatibility. As a polymer having the composition, for example, a block copolymer of polybutylene terephthalate and polyoxyalkylene glycol (polybutylene terephthalate is a highly compatible part with polyethylene terephthalate, and polyoxyalkylene glycol is polyethylene glycol). parts with low compatibility with terephthalate), various modified polyolefin resins (the modified functional group is the part with high compatibility with polyethylene terephthalate, and the polyolefin part has low compatibility with polyethylene terephthalate), etc. In addition, polymers with low compatibility with the main component polymer include various polyolefin resins and polymers that have melt viscosity characteristics close to those of the main component polymer (in this example, polyethylene terephthalate) at the melt extrusion temperature of the main component polymer. there is.

[Second Film]

The polymer A layer of the second film of the present invention preferably contains one or more types of polymers different from the polymer as the main component from the viewpoint of lowering the surface free energy after heating. The polymer, which is different from the main component polymer, has both a highly compatible portion and a low compatibility portion with the main component polymer from the viewpoint of lowering the surface free energy after heating and the viewpoint of achieving film quality. A hydrophobic polymer is preferably selected for the low compatibility portion.

As an example of the polymer A layer of the second film of the present invention, the main component is a polyester resin, and in the case of polyethylene terephthalate among the polyester resins, it has both a portion that is highly compatible with the polymer as the main component and a portion that has low compatibility. As a polymer having the composition, for example, a block copolymer of polybutylene terephthalate and polyoxyalkylene glycol (polybutylene terephthalate is a highly compatible part with polyethylene terephthalate, and polyoxyalkylene glycol is parts with low compatibility with polyethylene terephthalate), various modified polyolefin resins (parts in which modified functional groups are compatible with polyethylene terephthalate), etc. On the other hand, when combined with various surface treatments before heating, a method of directly copolymerizing polyethylene terephthalate with a structure with low compatibility with polyethylene terephthalate, such as polyoxyalkylene glycol, also lowers the surface free energy after heating. From this point of view, it is desirable.

[First and Second Films]

From the viewpoint of improving the appearance of the functional film and the smoothness characteristics of the first and second films of the present invention, the glossiness (60°) of the polymer A layer after heating at 180°C for 5 minutes is preferably 30 or more. Here, glossiness (60°) refers to the glossiness under the condition that the angle of incidence is 60°. The functional film has the property of reflecting electromagnetic waves, but is preferably smooth in order to improve various electrical characteristics when forming a circuit member by stacking multiple functional films, and as an indicator of the smoothness of the functional film from a macroscopic perspective, The glossiness of the polymer A layer onto which the functional film is transferred can be preferably used. The glossiness (60°) of the polymer A layer after heating at 180°C for 5 minutes is more preferably 50 or more, more preferably 70 or more, and especially preferably 80 or more. In addition, the glossiness (60°) on the polymer A layer side is preferably 200 or less, and more preferably 155 or less from the viewpoint of handling of the functional film.

A method for adjusting the glossiness (60°) of the polymer A layer after heating at 180°C for 5 minutes to the desired range is to adjust the types and sizes of various particles contained in the polymer A layer to provide winding properties. there is.

In the first and second films of the present invention, the indentation elastic modulus of the polymer A layer is 800 N/mm2 or more and 6,000 N/mm2 or less from the viewpoint of suppressing dents or traces of foreign matter in the film and improving the quality of the functional film. desirable. Here, the indentation elastic modulus, called the nanoindentation method, is an evaluation method that can measure the hardness and elastic modulus of a microscopic area or thin film. If the indentation elastic modulus is high, recovery from microscopic deformation in the thickness direction becomes easier, so the film is damaged when subjected to impact or Even if the foreign matter is wrapped in a state in which it is wrapped, it is difficult for dents or traces of the foreign matter to form, so the surface quality of the film can be improved, and the surface quality of the transferred functional film can be improved.

In the first and second films of the present invention, methods for adjusting the indentation elastic modulus of the polymer A layer to 800 N/mm2 or more and 6,000 N/mm2 or less include the composition of the film (melting point, alloy of two or more types of raw materials) and manufacturing conditions. A method of performing adjustment by (biaxial stretching processing, stretching temperature, stretching ratio, etc. in the processing), etc. can be mentioned.

When the first and second films of the present invention are used as a process substrate for obtaining a thin film of a functional material layer (functional film) by applying a functional material, from the viewpoint of improving handling, the main orientation axis direction and main orientation It is preferable that the tear propagation resistance in the direction perpendicular to the axis is 4.0 N/mm or more and 12.0 N/mm or less. Here, the tear propagation resistance refers to the value measured according to JIS K-7128-2-1998, and the larger the value, the more difficult it is to tear. In addition, the main orientation axis in the present invention is a direction determined using a microwave molecular orientation meter, and the direction orthogonal to the main orientation axis is a direction determined based on the main orientation axis direction using a microwave molecular orientation meter. In addition, the main orientation axis of the film is the in-plane orientation in which the molecular chains of the polymer constituting the film are most strongly oriented. A general measurement method other than a microwave molecular orientation meter is an automatic birefringence meter (Oji Scientific Instruments Co., Ltd.). It is possible to obtain it using an Abe refractometer (“DR-A1” series, “NAR” series, etc. manufactured by ATAGO CO., LTD.), etc. In addition, in a biaxially oriented film, the direction perpendicular to the main orientation axis is generally the direction in which the molecular chain orientation is weakest, so tearing occurs in two directions, the direction in which the molecular chain orientation is strongest and the direction in which the molecular chain orientation is weakest in the film plane. By determining the propagation resistance, the highest and lowest values of the tear propagation resistance within the film plane can be confirmed. In other words, by knowing the upper and lower limits of the tear resistance of the film, it is possible to confirm that the film has good handleability in any direction.

From the viewpoint of improving handleability when used as a process substrate, the tear propagation resistance is more preferably 4.5 N/mm or more, particularly preferably 5.5 N/mm or more, and most preferably 6.0 N/mm or more. Furthermore, the film of the present invention more preferably has a tear strength of 9.8 N/mm or less from the viewpoint of improving the peelability of the functional film after processing. As a method of keeping the tear strength of the film in the range of 4.0 N/mm to 12.0 N/mm, a layer containing only a small amount of a low-melting point polymer compared to the polymer that is the main component of the film, or a layer containing no low-melting point polymer A method in which a layer has a laminated structure in the film, the layer has a thickness of 50% or more and 95% or less of 100% of the total film thickness, and the total film thickness is set to a specific range can be mentioned.

When the first and second films of the present invention are used as process substrates, they can provide good applicability, peelability after processing, and scratch resistance, so they can be used as circuit members such as various conductive and magnetic materials and ceramic members, It can be preferably used in the manufacturing process of various functional films such as optical members.

The functional material constituting the functional membrane in the present invention refers to a material used in various products for the purpose of expressing functions based on the various physical and chemical properties of the material, and includes characteristics such as photosensitivity and heat sensitivity. Examples include polymer materials, adhesives, adhesive materials, optical materials, ceramics, metal materials, magnetic materials, etc. having .

Polymer materials having characteristics such as photosensitivity or heat sensitivity include acrylic resins that are cured by light such as ultraviolet rays or lasers, or heat, and are preferably used in various resist materials, printing inks, and surface protection applications for plastic materials. .

Adhesives and adhesives include materials such as acrylic resins, silicone resins, polyvinyl alcohol resins, and epoxy resins. They include sealants for semiconductor chips, conductive adhesives, sealants for electronic components such as displays, and die during semiconductor chip manufacturing. It is preferably used in processing applications such as thinning tape and plating masking tape.

Optical materials include materials with characteristics such as transparency and phase difference characteristics, such as acrylic resin, polycarbonate resin, and cyclic olefin resin, and are used for optical materials responsible for recording, displaying, and transmitting information, such as optical disks and flat panel displays. It is preferably used in, etc.

Ceramics include materials with characteristic dielectric properties and heat resistance, such as barium titanate, alumina, zirconium oxide, silicon carbide, and zeolite, and are suitable for use as capacitors, inductors, and circuit board materials used in various digital electronic devices such as smartphones. It is used widely.

Metal materials include materials characterized by conductivity, heat dissipation, electromagnetic wave shielding, and barrier properties, such as silver, copper, and iron, and are preferably used in metal transfer foil applications.

Magnetic materials include materials that have the characteristics of generating or deforming magnetic force in a magnetic field, or changing electrical resistance, such as ferrite and permalloy, and are preferably used in inductors, noise suppression, wireless communication, and wireless power supply applications.

[First and Second Films]

Next, a preferred method for producing the first and second films of the present invention will be described below as an example when a polyester resin is selected as the polymer A layer. The present invention is not to be construed as limited to these examples.

First, the raw materials constituting the polymer A layer are supplied to a vented twin-screw extruder and melt-extruded. When laminating polymer A layer and layers other than polymer A layer, polyester A used for polymer A layer and polyester raw material used for layers other than polymer A layer are supplied to separate vented twin-screw extruders. and melt and extrude. In addition, when polymer A layers of different compositions are laminated, the polyester A used for each polymer A layer is supplied to separate vented twin-screw extruders and melt-extruded. However, in the following, the polymer A layer and the polymer A layer are melt-extruded. The explanation is given as a configuration in which layers other than the A layer (referred to as the polymer B layer) are laminated. When performing melt extrusion, it is desirable to set the oxygen concentration to 0.7 volume% or less under a circulating nitrogen atmosphere in the extruder, and to set the extrusion temperature of the resin to be 5°C to 40°C higher than the melting point of the resin with the highest melting point in each layer. In the case of only amorphous resins whose melting points cannot be observed, it is desirable to adjust them within the range of, for example, 180°C to 270°C while observing the melt viscosity or melt state. Next, foreign substances are removed and the extruded amount is equalized through a filter or a gear pump, and the polymer A layer and the polymer B layer are joined, and then discharged in a sheet form from the T die onto the cooling drum. At that time, the electrostatic application method, which uses an electrode applied with high voltage to bring the cooling drum and resin into close contact with static electricity, the casting method, which installs a water film between the casting drum and the extruded polymer sheet, and the casting drum temperature is adjusted to the glass transition point of polymer A. (Glass transition point - 20°C) by adhering the extruded polymer, or by combining these methods, the sheet-like polymer is brought into close contact with the casting drum, cooled and solidified, and an unstretched film is obtained. Among these casting methods, when using a polyester resin, the electrostatic application method is preferably used from the viewpoint of productivity and planarity.

In addition, in the first film of the present invention, when the polymer A layer is composed of a combination of two or more types of polymers, a so-called side feed extruder, which allows raw materials to be introduced from the melting zone of the extruder, is used to form the polymer A layer. It is preferably used as an extruder. In addition, from the viewpoint of preventing the low melting point polymer from being heated excessively and lowering the melt viscosity, resulting in a non-uniform structure of the polymer A layer, a method of introducing a low melting point polymer among the polymers contained in the polymer A layer from the side feed side This is preferably used.

The first and second films of the present invention are preferably biaxially oriented from the viewpoint of heat resistance and dimensional stability, and the unstretched film is stretched in the longitudinal direction and then stretched in the width direction, or stretched in the width direction and then stretched in the longitudinal direction. It is preferable to carry out stretching by a sequential biaxial stretching method in which the film is stretched in multiple directions, or by a simultaneous biaxial stretching method in which the longitudinal direction and the width direction of the film are stretched almost simultaneously. The biaxial orientation state of the film can be determined, for example, in the case of a film composed mainly of polyester resin such as polyethylene terephthalate resin, by measuring the direction of the main orientation axis within the film plane and the main orientation axis within the film plane using an Abbe refractometer. The refractive index in the direction perpendicular to and the thickness direction of the film is measured, and it can be confirmed that the refractive index in the thickness direction of the film is the smallest.

The stretching ratio in this stretching method is preferably 2.7 times to 4 times, more preferably 3 to 3.5 times in the longitudinal direction. Additionally, the stretching speed is preferably 1,000%/min or more and 200,000%/min or less. Additionally, the stretching temperature in the longitudinal direction is preferably 80°C or higher and 130°C or lower. Additionally, the stretching ratio in the width direction is preferably 2.8 times or more and 4 times or less, and more preferably 3 times or more and 3.8 times or less. The stretching speed in the width direction is preferably 1,000%/min or more and 200,000%/min or less.

Additionally, heat treatment of the film may be performed after biaxial stretching. Heat treatment can be performed by any conventionally known method, such as in an oven or on a heated roll. Since the purpose of this heat treatment is to improve heat dimensional properties by growing oriented crystals after biaxial orientation, the heat treatment temperature is generally set as high as possible within the range below the melting point of the polymer A layer, which has the highest melting point. .

In addition, in the polymer A layer of the first film of the present invention, by containing a small amount of a polymer with a lower melting point than the main component of the polymer A layer, low-oriented domains are formed in the polymer A layer, and the polymer A layer after heating It can be designed to be easy to form surface deformation. When the polymer A layer is composed of a combination of two or more types of polymers, an orientation difference is provided between the polymer that is the main component of the polymer A layer and the polymer that has a lower melting point than the main component contained in the polymer A layer, and when processing the functional film, From the viewpoint of making it easier to form strain at the interface between the polymer A layer and the functional film due to the difference in orientation relaxation, the heat treatment temperature of the film after biaxial stretching is 25°C to 30°C higher than the melting point of the polymer with a low melting point. It is desirable to be

In addition, in the polymer A layer of the second film of the present invention, the main component of the polymer A layer is different from the polymer (it has a composition of both a portion with high compatibility with the polymer as the main component and a portion with low compatibility, and a polymer with low compatibility By constructing a structure in which a small amount of a hydrophobic polymer is contained in a highly compatible portion, after heating, portions (hydrophobic portions) with low compatibility between the main component and other polymers are arranged on the surface, increasing the surface free energy of the A layer. This can be done with a design that is easy to deteriorate.

In addition, the first and second films of the present invention are subjected to surface treatments such as corona treatment, plasma treatment, and UV treatment on the surface of the polymer A layer in order to improve adhesion to the functional film before heating and peelability after heating. Alternatively, the easily adhesive layer and the mold release layer may be coated during the film manufacturing process.

In particular, when the polymer A layer of the second film of the present invention contains a polymer containing a hydrogen moiety, the polymer containing a hydrophobic moiety is carried out under very mild conditions compared to the conditions for improving the hygroscopicity of the conventional film. By using a method of imparting kinetic energy to a range that does not impair adhesion to various functional films, the polarity of the polymer A layer can be controlled to a specific range to improve the characteristics and quality of the functional film.

Example

The method of measuring the characteristics and evaluating the effect in the present invention are as follows.

(1) Composition of polymer

The composition of the polymer A layer was determined using a known polymer composition analysis method (FT-IR (Fourier transform infrared spectrophotometer), NMR (nuclear magnetic resonance), etc.). In the case where polyester is included in the polymer A layer, the polymer A layer is scraped off from the film, dissolved in hexafluoroisopropanol (HFIP), and each monomer residue is identified using ¹ H-NMR and ¹³ C-NMR. The content of ingredients and by-product diethylene glycol was quantified. In addition, for the film of the present invention, the composition was calculated by calculation from the mixing ratio at the time of film production.

(2) Intrinsic viscosity

When it is confirmed that the polymer A layer tends to be polyester by known polymer composition analysis methods (FT-IR, NMR, etc.), the polymer A layer is dissolved in ortho chlorophenol and measured at 25°C using an Oswald viscometer. did. In the case of a laminated film, the intrinsic viscosity of each layer was evaluated by cutting off each layer of the film according to the lamination thickness.

(3) Film thickness, layer thickness

When measuring the film thickness, a dial gauge was used to measure the thickness at five random locations on the sample cut from the film, and the average value was obtained. When measuring the layer thickness, the film was embedded in epoxy resin, and the cross section of the film was cut with a microtome. The cross section was observed at a magnification of 5000 times using a transmission electron microscope (TEM H7100 manufactured by Hitachi, Ltd.), and the thickness of each layer was determined.

(4) Melting point

A differential scanning calorimeter (SII Nano Technology Inc. (formerly Seiko Instruments & Electronics Ltd., EXTRA DSC6220) was used to measure and analyze the film in accordance with JIS K-7121-1987 and JIS K-7122-1987. 5 mg was used in the sample, and the temperature at the peak of the endothermic peak obtained from the DSC curve when the temperature was raised from 25°C to 300°C at 20°C/min was taken as the melting point. In the case of a laminated film, each layer of the film was cut. The melting point of each layer alone was measured, and when multiple melting points were observed, the endothermic peak with the largest area was adopted as the melting point of the layer.

(5) Rm1, Ra1

In an AFM (atomic force microscope) such as "Nano ScopeV Dimension Icon" manufactured by Bruker AXS, a silicon cantilever was applied as a probe, and the surface shape of a film or a film heat-treated at 180°C for 5 minutes was measured in tapping mode. . In addition, the scanning range was 3 μm × 3 μm, the scanning speed was 0.4 Hz, and the measurement was performed at room temperature (25°C) in the air. In addition, as a preprocessing for measurement, the film was cut to about 1 cm x 1 cm and fixed to a silicon wafer with epoxy resin before measurement. Afterwards, using software attached to AFM (e.g. Nano Scope Analysis, etc.), the maximum height and arithmetic mean illuminance were calculated under the condition of a cutoff of 3 nm, and the average value of 5 measurements was calculated for each. The measurement direction (scanning direction of the probe) is measured in an arbitrary direction and in two directions perpendicular to the arbitrary direction, and the maximum height in each direction and each average value of the arithmetic mean illuminance (i.e., 5 in any one direction) are measured. The average value of 10 measurements (a total of 5 measurements in a direction orthogonal to one direction) was adopted as Rm1 (nm) and Ra1 (nm), respectively.

(6) Rm2, Ra2

A sample was prepared by sandwiching an A4-size film between two 2-mm-thick aluminum frames with the width of 1 cm on all four sides cut out, and then fixing the aluminum frames with metal clips. After that, heat treatment of the film was performed in a conveyor-type oven (manufactured by Fujimak Corporation, FGJOA9H) set at 180°C, with the oven passage time set to 5 minutes. For the film obtained by the above method after heating at 180°C for 5 minutes, the maximum height and arithmetic mean roughness by AFM were calculated in the same manner as (5), and the average value of 5 measurements was calculated for each. The measurement direction (scanning direction of the probe) is measured in an arbitrary direction and in two directions perpendicular to the arbitrary direction, and the maximum height in each direction and each average value of the arithmetic mean illuminance (i.e., 5 in any one direction) are measured. The average value of 10 measurements (a total of 5 measurements in a direction perpendicular to one direction) was adopted as Rm2 (nm) and Ra2 (nm), respectively.

(7) Indentation elastic modulus

Using a nanoindenter (manufactured by Elionix Inc., ENT-2100), apply 1 drop of “Aron Alpha Professional Impact Resistance” (manufactured by Toagosei Co., Ltd., adhesive) to one side of the film, and fix it on the sample fixture. , the remaining surface was measured as the measurement surface. For the measurement, a triangular diamond indenter (Berkovich indenter) with an interradial angle of 115° was used. The measurement data was processed using dedicated analysis software (version 6.18) for “ENT-2100” to determine the indentation elastic modulus. After that, the same measurement was performed with the measurement surface reversed, and the indentation elastic modulus of both surfaces was determined.

(8) Scar resistance

A 5 mm × 5 mm polyester film piece (manufactured by Toray Industries, Inc., “Lumirror” S10 (50 μm)) placed on an iron plate was coated with the film used for evaluation in an overlapping manner of 10 sheets. After that, a 500 g spindle (cylindrical shape with a diameter of 20 mm and a height of 28 mm) was left at the position covered with the polyester film piece for 1 hour. Afterwards, the spindle was removed, each film was photographed with a non-contact surface/layer cross-section shape measurement system (VertScan 2.0 RG300GL-Lite-AC, manufactured by Ryoka Systems Inc.), and the photographed screen was converted to polynomial 4 using the included analysis software. Surface correction was performed using difference approximation, and the surface shape was measured. Out of a total of 10 sheets, the number of films in which a step difference of 5 μm or more was confirmed was evaluated based on the following criteria. In addition, the camera used for filming was Sony HR-57 (1/2 inch), the wavelength filter was 530 nm white, the measurement software was VS-Measure Version 5.5.1, and the analysis software was VS-Viewer Version 5.5.1. were used respectively.

A: 2 or less

B: 3 or more but 4 or less

C: 5 or more sheets.

(9) Adhesion to functional membrane (Method 1)

A ferrite-based slurry was applied as a functional film to the polymer A layer side of the film so that the thickness after drying was 20 μm. In addition, the ferrite-based slurry contains 100 parts of soft magnetic ferrite powder (number average particle diameter 0.7 μm), 30 parts of polyvinyl butyral resin (“S-LEC BM-S” manufactured by Sekisui Chemical Co., Ltd.), and a plasticizer ( A slurry consisting of 5 parts of dioctyl phthalate and 200 parts of toluene/ethanol mixed solvent (mixing ratio: 6:4) was used, and the drying conditions were 100°C for 5 minutes. An OPP adhesive tape (DANPRON S No. 375) manufactured by Nitto Denko Corporation was bonded to the functional film side of the obtained film/functional film (a layer obtained by drying the ferrite-based slurry), and cut into a rectangle with a width of 10 mm and a length of 150 mm to serve as a sample. did. A part of the sample was peeled from the film/functional membrane layer, and using a tensile tester (TENSILON UCT-100, manufactured by Orientec Co. Ltd.), the distance between the initial tensile chucks was 100 mm and the tensile speed was 20 mm/min, and then stretched at 180°. A peel test was performed. Measurements were performed until the peeling length reached 130 mm (distance between chucks 230 mm), and the average value of the load for the peeling length of 25 mm to 125 mm was taken as the peeling strength. In addition, measurements were performed 5 times, and the average value was adopted. With respect to the peel strength obtained in this way, adhesion to the functional film was evaluated based on the following criteria.

A: 0.030N/10mm or more, or peeling is not possible

B: 0.010N/10mm or more but less than 0.030N/mm

C: Less than 0.010N/10mm.

(10) Peelability from functional membrane (Method 1) (after heating)

After producing the film/functional membrane layer as in (9), heat treatment at 180°C for 5 minutes was performed in the same manner as (6). After that, the peeling strength was calculated in the same manner as (9). Thereafter, the peel strength obtained in (9) was compared with the peel strength after heat treatment at 180°C for 5 minutes, and the effect of improving peelability after heating was evaluated based on the following criteria.

A: After heating at 180°C for 5 minutes, the peeling strength was lowered by 0.01N/10mm or more, or items that were not peelable became peelable.

B: After heating at 180°C for 5 minutes, the peeling strength decreased by more than 0.005 N/10 mm and less than 0.01 N/10 mm.

C: After heating at 180°C for 5 minutes, the peel strength exceeded 0 N/10 mm and decreased to less than 0.005 N/10 mm.

D: After heating at 180°C for 5 minutes, the peel strength did not change or the peel strength increased.

(11) Smoothness of functional membrane (Method 1)

For the functional film peeled from the film in the same manner as in (10), the air inflow time from the gap between the glass and the functional film was measured using a Beck-type smoothness tester (made by KUMAGAI RIKI KOGYO Co., Ltd., type HK). and evaluated based on the following criteria. In addition, when the air inflow time is long, the gap through which air flows is small even when functional membranes are stacked, which is an advantageous indicator in terms of electrical characteristics and miniaturization of members in applications where functional membranes are stacked. In addition, the measurement conditions were that the measurement area was 10 cm2, the pressurized pressure for fixing the functional film on the glass was 100 kPa, the pressure on the vacuum side at the start of the measurement was 0.05 MPa, the pressure on the atmospheric side was 0.1 MPa, and the pressure was increased from 0.051 MPa to 0.052 MPa. This changing time was referred to as the air inflow time.

A: More than 20 minutes

B: More than 5 minutes but less than 20 minutes

C: More than 1 minute but less than 5 minutes

D: Less than 1 minute.

(12) Glossiness of polymer A layer after heating at 180℃ for 5 minutes

The film subjected to heat treatment at 180°C for 5 minutes in the same manner as in (6) was tested by Suga Test Instruments Co. in accordance with the method specified in JIS Z-8741-1997. Using a digital color change gloss meter UGV-5D manufactured by Ltd., the 60° specular gloss of the polymer A layer side was measured. The measurement was performed at n=5, and the average value excluding the maximum and minimum values was taken as the glossiness. In addition, when measuring glossiness, black drawing paper (manufactured by King Corporation, GK8012 (thickness 0.19 mm)) was placed on the back side of the measurement surface of the film and the measurement was performed.

(13) Main orientation axis direction, direction perpendicular to the main orientation axis direction

A sample with a size of 100 mm , the direction of the main orientation axis within the plane of the polyester film was determined. Additionally, based on the obtained main orientation axis direction, the direction orthogonal to the main orientation axis direction was also determined.

(14) Tear propagation resistance

Measurements were made according to JIS K-7128-2-1998 using a heavy load tear tester (manufactured by Toyo Seiki Seisaku-sho, Ltd.). The sample is 75 mm The value was read and the tearing force (N) in the main orientation axis direction was obtained. Next, the tearing force (N) in the main orientation axis direction, which was read from the indicated value, was divided by the film thickness (mm) to obtain the tear propagation resistance in the main orientation axis direction. In addition, measurements were performed 10 times each, and the average value of the 10 measurements was adopted. In addition, measurements were performed in the same manner as above except that the measurement samples were 75 mm x 63 mm in the direction perpendicular to the main orientation axis and the direction perpendicular to the main orientation axis, and the tear propagation resistance in the direction perpendicular to the main orientation axis was determined.

(15) Surface roughness

Measurements were made on both sides using a surface roughness meter (SE4000 manufactured by Kosaka Kenkyusho Co., Ltd.). Measurements were made under the conditions of a stylus tip radius of 0.5 μm, a measurement force of 100 μN, a measurement length of 1 mm, a low-pass cutoff of 0.200mm, and a high-pass cutoff of 0.000mm, and the arithmetic mean roughness SRa was determined based on JIS B0601-2001.

(16) Padan believer

After obtaining the main orientation axis direction and the direction perpendicular to the main orientation axis direction by the method of (13), a sample was produced by cutting into a rectangle of 150 mm × 30 mm (main orientation axis direction × direction perpendicular to the main orientation axis direction). . The sample was set on a tensile tester (TENSILON UCT-100 manufactured by Orientec Co. Ltd.) so that the test length (initial tensile distance between chucks (Sa)) was 50 mm, and the distance between chucks when the sample broke at a tensile speed of 300 mm/min. (Sb) was obtained. Sa and Sb were measured 10 times, and the average value of the 10 measurements was determined using the formula (Sb-Sa)/Sa x 100, which was used as the breaking elongation (%) in the main orientation axis direction. In addition, the breaking elongation (%) in the direction perpendicular to the main orientation axis direction was also determined by measuring using a rectangular sample of 150 mm x 10 mm (direction perpendicular to the main orientation axis direction x main orientation axis direction).

(17) Breaking strength

When the breaking elongation in the main orientation axis direction was determined by the method in (16), the stress when the sample broke was read 10 times, and the average value of the 10 times was taken as the breaking strength in the main orientation axis direction (MPa). In addition, when the breaking elongation in the direction orthogonal to the main orientation axis direction was obtained by the method of (16), the stress when the sample fractured was read 10 times, and the average value of the 10 times was calculated as the fracture elongation in the direction orthogonal to the main orientation axis direction. It was set as strength (MPa).

(18) Processability (Method 1)

A 300 mm wide, 200 m long (6 inch, 350 mm long core winding) film was prepared, rewound on a 3 inch, 350 mm long core under the following conditions, and evaluation was performed based on the following criteria while changing the conveyance speed and tension.

A: No tearing occurred even when rewound at a speed of 10 m/min and a conveyance tension of 70 N/m.

B: No tearing occurred even when rewound at a speed of 5 m/min and a conveyance tension of 50 N/m, but tearing occurred when the speed was changed to 10 m/min and a conveyance tension of 70 N/m.

C: No tearing occurred even when rewound at a speed of 5 m/min and a conveyance tension of 35 N/m, but tearing occurred when rewound at a speed of 5 m/min and a conveyance tension of 50 N/m.

D: Tearing occurred even after rewinding at a speed of 5 m/min and a conveyance tension of 35 N/m.

(19) Surface free energy SE1

A contact angle meter (CA-D type, manufactured by Kyowa Interface Science, Inc.) was used for a film that had been subjected to humidity control for 24 hours under conditions of 23°C and 65%RH, and was measured using water, ethylene glycol, formamide, and methylene iodide. Using various measuring liquids, the static contact angle with respect to the film surface was determined using a contact angle meter CA-D type manufactured by Kyowa Interface Science, Inc. The contact angle obtained for each liquid and each component of the surface tension of the measured liquid were respectively substituted into the equations below, and a simultaneous equation consisting of four equations was solved for γ ^L , γ ⁺ , and γ ^- .

However, γ=γ ^L + 2(γ ⁺ γ ^- ) ^{1/ 2} γ _j = γ _j ^L + 2(γ _j ⁺ γ _j ^- ) ^1/2 Here, γ, γ ^L , γ ⁺ , γ ^- are γ _j , γ _j ^L , γ j + , and γ j - are the surface free energy of the film surface, long-range force term, Lewis acid parameter, and Lewis base parameter, respectively, and γ j , γ j L , γ _j ⁺ , and γ _j ^- are the surface free energy and long-range force term of the measurement liquid used, respectively. This refers to Lewis acid parameters and Lewis base parameters.

The surface tension of each liquid used here was the value in Table 1 suggested by Oss ("Fundamentals of Adhesion", L. H. Lee (Ed.), p.153, Plenum ess, New York (1991)). In addition, the average value of five measurements was adopted as the static contact angle for each measurement liquid.

(20) Surface free energy SE2

A sample was prepared by sandwiching an A4-size film between two 2-mm-thick aluminum frames with the width of 1 cm on all four sides cut out, and then fixing the aluminum frames with metal clips. After that, heat treatment of the film was performed in a conveyor-type oven (manufactured by Fujimak Corporation, FGJOA9H) set at 180°C, with the oven passage time set to 5 minutes. For the film obtained by the above method and heated at 180°C for 5 minutes, the surface free energy was determined in the same manner as (19), and was set as SE2.

(21) Adhesion to functional membrane (Method 2)

On the polymer A layer side of the film, a conductive paste was applied as a functional film so that the thickness after drying was 20 μm. As a conductive paste, 100 parts by mass of an epoxy adhesive (“AS-60” manufactured by Toagosei Co., Ltd.) is mixed with 50% silver-coated copper powder (Fukuda Metal Foil & Powder Co., Ltd.) with a particle diameter (median diameter) of 5.9 μm. A mixture of 150 parts by mass of "Cu-HWQ5 ㎛" manufactured by Ltd. was used, and the drying conditions were 100°C for 5 minutes. An OPP adhesive tape (DANPRON S No. 375) manufactured by Nitto Denko Corporation was bonded to the functional film side of the obtained film/functional film (layer obtained by drying the conductive paste), and cut into a rectangle with a width of 10 mm and a length of 150 mm to prepare a sample. . A part of the sample was peeled between the film/functional membrane and peeled at 180° using a tensile tester (TENSILON UCT-100, manufactured by Orientec Co. Ltd.) with an initial tensile chuck distance of 100 mm and a tensile speed of 20 mm/min. conducted a test Measurements were performed until the peeling length reached 130 mm (distance between chucks 230 mm), and the average value of the load for the peeling length of 25 mm to 125 mm was taken as the peeling strength. In addition, measurements were performed 5 times, and the average value was adopted. With respect to the peel strength obtained in this way, adhesion to the functional film was evaluated based on the following criteria.

A: More than 0.030N/10mm or peeling is not possible

B: 0.010N/10mm or more but less than 0.030N/mm

C: Less than 0.010N/10mm.

(22) Peelability from functional membrane (Method 2) (after heating)

After producing the film/functional membrane in the same manner as in (21), heat treatment at 180°C for 5 minutes was performed in the same manner as in (20). After that, the peeling strength was calculated in the same manner as (21). After that, the peel strength obtained in (21) was compared with the peel strength after heat treatment at 180°C for 5 minutes, and the effect of improving peelability after heating was evaluated based on the following criteria.

A: After heating at 180°C for 5 minutes, the peeling strength was lowered by 0.01N/10mm or more, or what was not peelable became peelable.

B: After heating at 180°C for 5 minutes, the peeling strength decreased by more than 0.005 N/10 mm and less than 0.01 N/10 mm.

C: After heating at 180°C for 5 minutes, the peel strength exceeded 0 N/10 mm and decreased to less than 0.005 N/10 mm.

D: After heating at 180°C for 5 minutes, the peel strength did not change or the peel strength increased.

(23) Uniformity of functional membranes

After producing the film/functional membrane similarly to (21), the surface resistivity of the functional membrane was measured and evaluated based on the following criteria. When the composition of the functional film is uniform, the metal contained in the functional film is uniformly dispersed, making it easier for current to flow, so the surface resistivity decreases and serves as an indicator of the uniformity of the functional film. Additionally, as a method of measuring surface resistivity, the film is cut to 200 mm Measurements were made using (manufactured by Advantest Corporation), the average value of 10 measurements was obtained, and evaluation was made based on the following criteria.

A: 1.0×10 ⁸ Ω/sq or less

B: Exceeding 1.0×10 ⁸ Ω/sq and less than or equal to 1.0×10 ¹³ Ω/sq

C: Exceeding 1.0×10 ¹³ Ω/sq and less than or equal to 1.0×10 ¹⁵ Ω/sq

D: Value exceeding 1.0×10 ¹⁵ Ω/sq

(24) Sd2, Sp2

For the film subjected to heat treatment at 180°C for 5 minutes in the same manner as (20), the dispersion force Sd2 and polarity Sp2 were determined as follows. First, the following equation (e) was derived from the extended Fowkes equation and Young's equation.

[Extended Fowkes style]

[Young’s ceremony]

γS = γSL + γLcosθ

γS: surface free energy of solid

γL: surface tension of liquid

γSL: Interfacial tension of solid and liquid

θ: contact angle with liquid

γsd, γLd: Dispersion force components of γS, γL

γsD, γLD: Polar force components of γS and γL

γsh, γhL: Hydrogen bond components of γS, γL

Next, for four types of liquids whose surface tension components are known, the contact angle with the film subjected to heat treatment at 180°C for 5 minutes was measured, and substituted into equation (e) to obtain the 3-way first order for each liquid. By solving the simultaneous equations, the dispersion force component γsD in the surface free energy of the film subjected to heat treatment at 180°C for 5 minutes was adopted as Sd2, and the polar force component γsD was adopted as Sp2. The numerical calculation software “Mathematica” was used to solve the simultaneous equations. In addition, for measuring the contact angle, measuring liquids of water, ethylene glycol, formamide, and methylene iodide were used, and a CA-D contact angle meter manufactured by Kyowa Interface Science, Inc. was used as a measuring instrument. In addition, the static contact angle in each measurement liquid was the average value of five measurements.

(25) Processability (Method 2)

A 300 mm wide, 200 m long (6 inch, 350 mm long core winding) film was prepared, rewound on a 3 inch, 350 mm long core under the following conditions, and evaluation was performed based on the following standards while changing the conveyance speed and tension.

A: No tearing occurred even when rewound at a speed of 10 m/min and a conveyance tension of 70 N/m.

B: No tearing occurred even when rewound at a speed of 5 m/min and a conveyance tension of 50 N/m, but tearing occurred when the speed was changed to 10 m/min and a conveyance tension of 70 N/m.

C: Tearing occurred when rewound at a speed of 5 m/min and a conveyance tension of 50 N/m.

(26) Smoothness of functional membranes (Method 2)

The functional film peeled from the film in the same manner as (22) was placed under a fluorescent light, and the visible image of the fluorescent light was evaluated based on the following criteria.

A: I could clearly see the outline of the fluorescent light.

B: The outline of the fluorescent lamp was vaguely visible, but the condition of the fluorescent lamp could be roughly confirmed.

C: The outline of the fluorescent light could hardly be seen.

(27) Main orientation axis direction, direction perpendicular to the main orientation axis direction

A sample was cut to a size of 100 mm Thus, the direction of the main orientation axis within the plane of the polyester film was determined. Additionally, based on the obtained main orientation axis direction, the direction orthogonal to the main orientation axis direction was also determined.

The following resin was used to produce the film of the present invention.

(polyester 1)

After producing a polyethylene terephthalate resin containing 100 mol% of terephthalic acid as a dicarboxylic acid component and 100 mol% of ethylene glycol as a glycol component, silica particles with a number average particle diameter of 2.2 μm were added to 100% by mass of the polyethylene terephthalate resin. Particle-containing polyethylene terephthalate resin containing 0.04% by mass (intrinsic viscosity 0.63, melting point 255°C).

(polyolefin 2)

As a modified polyolefin resin to which maleic anhydride is bonded, "Yumex" 1001 (melting point 142°C) manufactured by Sanyo Chemical Industries, Ltd. was used.

(polyester 3)

A polyester resin (intrinsic viscosity 1.1, melting point 215°C) obtained by block copolymerizing 90% by mass of polybutylene terephthalate and 10% by mass of polytetramethylene glycol was used.

(polyolefin 4)

As a polypropylene-based resin, R101 (MFR=19, melting point 163°C) manufactured by Sumitomo Chemical Co., Ltd. was used.

(polyolefin 5)

As a cyclic polyolefin resin, "TOPAS" 8007F-04 (no melting point) manufactured by Polyplastics Co., Ltd. was used.

(polyolefin 6)

It is a modified polyolefin-based resin in which a polyethylene-based main chain is bonded to a side chain in which part of the hydrogen ion of methacrylic acid (carboxylic acid) is replaced with a metal ion. “Himiran” 1707 (melting point 90°C) manufactured by Mitsui-Dupont Polychemical K.K. ) was used.

(Acrylic 7)

A resin coating agent containing 26% by mass of heat-expandable microspheres (Microsphere F-50) with respect to 74% by mass of "FINETACK" CT-3088 manufactured by DIC Corporation was used.

(polyester 8)

After producing a polyethylene terephthalate resin containing 100 mol% of terephthalic acid as a dicarboxylic acid component and 100 mol% of ethylene glycol as a glycol component, silica particles with a number average particle diameter of 3.5 μm were added to 100% by mass of the polyethylene terephthalate resin. 5% by mass of particle-containing polyethylene terephthalate resin (intrinsic viscosity 0.63, melting point 255°C).

(polyester 9)

A polyester resin (intrinsic viscosity 1.0, melting point 213°C) obtained by block copolymerizing 85% by mass of polybutylene terephthalate and 15% by mass of polytetramethylene glycol was used.

(polyester 10)

A polyester resin (intrinsic viscosity 1.4, melting point 218°C) obtained by block copolymerizing 90% by mass of polybutylene terephthalate and 10% by mass of polytetramethylene glycol was used.

(polyester 11)

After producing a polyethylene terephthalate resin containing 100 mol% of terephthalic acid as a dicarboxylic acid component and 100 mol% of ethylene glycol as a glycol component, silica particles with a number average particle diameter of 3.5 μm were added to 100% by mass of the polyethylene terephthalate resin. Particle-containing polyethylene terephthalate resin containing 20% by mass (intrinsic viscosity 0.65, melting point 255°C).

(polyester 12)

After producing a polyethylene terephthalate resin containing 100 mol% of terephthalic acid as a dicarboxylic acid component and 100 mol% of ethylene glycol as a glycol component, silica particles with a number average particle diameter of 2.2 μm were added to 100% by mass of the polyethylene terephthalate resin. Particle-containing polyethylene terephthalate resin containing 0.04% by mass (intrinsic viscosity 0.63).

(polyolefin 13)

As a modified polyolefin resin to which maleic anhydride is bonded, "Yumex1001" manufactured by Sanyo Chemical Industries, Ltd. was used.

(polyester 14)

A resin (intrinsic viscosity 0.57) obtained by block copolymerizing 90% by mass of polybutylene terephthalate and 10% by mass of polytetramethylene glycol was used.

(polyolefin 15)

As the polypropylene-based resin, “R101” (MFR=19) manufactured by Sumitomo Chemical Co., Ltd. was used.

(polyolefin 16)

As a cyclic polyolefin resin, "TOPAS8007F-04" manufactured by Polyplastics Co., Ltd. was used.

(Acrylic 17)

A resin coating agent containing 74% by mass of "FINETACKCT-3088" manufactured by DIC Corporation and 26% by mass of heat-expandable microspheres (Microsphere F-50) was used. Isophthalic acid copolymerization polyethylene terephthalate resin (intrinsic viscosity 0.7, melting point 230°C) containing 90 mol% terephthalic acid as a dicarboxylic acid component, 10 mol% isophthalic acid component, and 100 mol% ethylene glycol component as a glycol component.

(polyester 18)

After producing a tetramethylene glycol copolymerized polyethylene terephthalate resin containing 100 mol% of terephthalic acid as a dicarboxylic acid component, 99.3 mol% of ethylene glycol as a glycol component, and 0.7 mol% of tetramethylene glycol, a number average particle diameter of 2.2 A particle-containing polyethylene terephthalate resin (intrinsic viscosity 0.65) containing 0.04% by mass of ㎛ silica particles based on 100% by mass of the polyethylene terephthalate resin.

(polyester 19)

As a resin obtained by block copolymerizing polybutylene terephthalate and polytetramethylene terephthalate, “Hytrel” 7247 manufactured by DuPont-Toray Co., Ltd. was used.

(Example 1)

With the composition as shown in the table, polyester 1 is supplied to the normal feeder of a vented co-direction twin-screw extruder with an oxygen concentration of 0.2 volume%, and polyolefin 2 is supplied from the side feeder of the co-direction twin-screw extruder, and the polymer A layer The extruder was melted at a cylinder temperature of 280°C, and discharged in the form of a sheet onto a cooling drum whose temperature was controlled at 280°C at the single tube temperature and at 280°C at the spinneret temperature at 25°C from the T die. At that time, electrostatic application was applied using a wire-shaped electrode with a diameter of 0.1 mm, and the sheet was brought into close contact with a cooling drum to obtain an unstretched sheet. Next, it was stretched 3.5 times in the longitudinal direction at a stretching temperature of 85°C, and immediately cooled with a metal roll temperature-controlled to 40°C. Next, preheating was performed for 1.5 seconds at a preheating temperature of 85°C using a tenter-type transverse stretching machine, and the material was stretched 3.5 times in the width direction at a stretching temperature of 100°C, and heat treatment was performed as it was in the tenter at a heat treatment temperature of 245°C. Furthermore, heat treatment was performed while shortening the film by 5% in the width direction to obtain a biaxially oriented polyester film with a film thickness of 50 μm.

(Examples 2, 3, 6, 7, 8, 9, 11, 18, 19, 20, 21)

A biaxially oriented polyester film was obtained in the same manner as in Example 1, except that the composition and manufacturing conditions were changed as shown in the table.

(Example 4)

The composition was as shown in the table, and the raw materials were supplied to separate vented co-directional twin screw extruders with an oxygen concentration of 0.2 volume%. For the polymer A layer, polyester 1 was normally supplied to the feeder, polyolefin 2 was supplied from a side feeder, and the cylinder temperature of the extruder for the polymer A layer was set to 280°C to melt the raw materials. For the polymer B layer, polyester 1 was normally supplied to a feeder, and the extruder cylinder temperature was set to 280°C to melt the raw material. Thereafter, the raw materials for the polymer A layer and polymer B layer melted in each extruder were biaxially oriented in the same manner as in Example 1, except that they were joined to form a two-layer structure of the A layer and B layer in the feed block. A polyester film was obtained.

(Example 5, 13, 14, 15, 16, 17, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36)

A biaxially oriented polyester film was obtained in the same manner as in Example 4, except that the thickness of each layer was as shown in the table.

(Example 10)

Acrylic 7 was applied to a biaxially oriented polyester film, “Lumirror” S10 (100 μm) manufactured by Toray Industries, Inc., and dried at 80°C for 3 minutes to obtain a laminated film of polyester film and Acrylic 7.

(Example 12)

A biaxially oriented polyester film was obtained in the same manner as in Example 1, except that both polyester 1 and polyolefin 2 were supplied from a normal feeder.

(Example 37)

A biaxially oriented polyester film was obtained in the same manner as in Example 12, except that the composition was as shown in the table.

(Comparative Examples 1 and 2)

A biaxially oriented polyester film was obtained in the same manner as in Example 1, except that the composition and manufacturing conditions were changed as shown in the table.

(Reference Example 1)

With the composition as shown in the table, the raw materials are supplied to a vented co-directional twin-screw extruder with an oxygen concentration of 0.2% by volume, and the polymer A layer is melted at a cylinder temperature of 280°C, the single tube temperature is 280°C, and the spindle temperature is 280°C. was discharged in the form of a sheet from a T-die at 280°C onto a cooling drum whose temperature was controlled at 25°C. At that time, electrostatic application was applied using a wire-shaped electrode with a diameter of 0.1 mm, and the sheet was brought into close contact with a cooling drum to obtain an unstretched sheet. Next, it was stretched 3.5 times in the longitudinal direction at a stretching temperature of 85°C, and immediately cooled with a metal roll temperature-controlled to 40°C. Next, preheating is performed for 1.5 seconds at a preheating temperature of 85°C using a tenter-type transverse stretching machine, stretching is 3.5 times in the width direction at a stretching temperature of 100°C, and heat treatment is performed at a heat treatment temperature of 245°C while shortening the material by 5% in the width direction within the tenter. was done. After that, the E value, which is the target irradiation intensity of corona surface treatment, was applied to the obtained film (=treatment intensity (W)/(treatment electrode width (m)×film transport speed during corona surface treatment (m/min)) of 1W Corona surface treatment was performed at a setting of min/m2, and a biaxially oriented polyester film with a film thickness of 50 μm was obtained.

(Reference Examples 2, 3, 6, 7, 8, 11, 15, 16, 20, 21)

A biaxially oriented polyester film was obtained in the same manner as Reference Example 1 except that the composition and manufacturing conditions were changed as shown in the table.

(Reference Examples 4, 10, 12)

A biaxially oriented polyester film was obtained in the same manner as in Reference Example 1 except that the composition and manufacturing conditions were as shown in the table and the E value in the corona surface treatment was set to 60 W·min/m2.

(Reference Example 5)

A biaxially oriented polyester film was obtained in the same manner as Reference Example 4, except that the E value of the corona surface treatment was changed to 50 W·min/m2.

(Reference Examples 13, 17, 18)

Using the composition and manufacturing conditions as shown in the table, the raw materials are supplied to separate vented co-directional twin screw extruders with an oxygen concentration of 0.2% by volume, the cylinder temperature of the extruder for the polymer A layer is 280°C, and the cylinder temperature of the extruder for the B layer is set to 280°C. was melted at 280°C, and a biaxially oriented polyester film was obtained in the same manner as Reference Example 1, except that it was joined to form a two-layer structure of A layer/B layer in the feed block.

(Reference Example 9)

Acrylic 6 was applied to a biaxially oriented polyester film, “Lumirror” S10 (100 μm) manufactured by Toray Industries, Inc., and dried at 80°C for 3 minutes to obtain a laminated film of polyester film and acrylic 17.

(Reference Example 14)

A biaxially oriented polyester film was obtained in the same manner as Reference Example 1, except that the composition and manufacturing conditions were as shown in the table, and no corona surface treatment was performed.

(Reference Example 19)

Using the composition and manufacturing conditions as shown in the table, the raw materials are supplied to separate vented co-directional twin screw extruders with an oxygen concentration of 0.2% by volume, the cylinder temperature of the extruder for the polymer A layer is 280°C, and the cylinder temperature of the extruder for the B layer is set to 280°C. A biaxially oriented polyester film was obtained in the same manner as Reference Example 1, except that it was melted at 280°C and joined to form a three-layer structure of A layer/B layer/A layer in the feed block.

(Reference Comparative Examples 1 and 2)

A biaxially oriented polyester film was obtained in the same manner as Reference Example 1 except that the composition and manufacturing conditions were changed as shown in the table.

(Industrial applicability)

Since the first and second films of the present invention can improve adhesion before heating and peelability after heating, they are preferably used as a process substrate for applying a functional material to obtain a thin film of the functional material (functional film).

Claims (9)

A film having a polymer A layer on at least one side, wherein the main component of the polymer A layer is a polyester resin, and a polymer different from the polyester resin of which the polymer A layer is the main component is a polybutylene terephthalate component and polyoxyalkylene glycol. Contains a block copolymer of ingredients,
When the maximum height of the polymer A layer determined by AFM is Rm1 (nm) and the maximum height of the polymer A layer determined by AFM after heat treatment at 180°C for 5 minutes is Rm2 (nm), the following formula (II-2) satisfied,
A film characterized in that the glossiness (60°) of the polymer A layer after heat treatment at 180°C for 5 minutes is 69 or more.
1.6nm ≤ (Rm2-Rm1) ≤ 100nm···(II-2) According to claim 1,
A film that satisfies the following formula (III) when the arithmetic mean roughness of the polymer A layer determined by AFM after heat treatment at 180°C for 5 minutes is Ra2 (nm).
6 ≤ (Rm2/Ra2) ≤ 15···(III) According to claim 1,
When the arithmetic average roughness of the polymer A layer determined by AFM is Ra1 (nm), and the arithmetic average roughness of the polymer A layer determined by AFM after heat treatment at 180°C for 5 minutes is Ra2 (nm), the following formula (IV) A satisfying film.
(Rm2/Ra2) - (Rm1/Ra1) > 0···(IV) delete delete delete According to claim 1,
A film in which the polymer A layer has an indentation elastic modulus of 800 N/mm2 or more and 6,000 N/mm2 or less. According to claim 1,
A film having a tear propagation resistance of 4.0 N/mm or more and 12.0 N/mm or less in the main orientation axis direction and the direction perpendicular to the main orientation axis. According to claim 1,
Films used in manufacturing process applications.