KR102633961B1 - film - Google Patents

Abstract

A film having a low gloss layer (A layer) having both a 60° glossiness (G ₆₀ ) and an 85° glossiness (G ₈₅ ) of 27 or less, wherein the 60° glossiness (G ₆₀ ) and the 85° glossiness (G 85 ) are both 27 or less. G ₈₅ ) provides a film that satisfies 0.1≤(G ₈₅ )/(G ₆₀ )≤3 and can transfer a uniform, low-gloss appearance regardless of the angle of incidence when used as a transfer film.

Description

film

The present invention relates to films.

Recently, with the expansion of smartphones and tablets and the integration of circuits, printed wiring boards have become increasingly high-precision and high-density. In the manufacturing process of a printed wiring board, a circuit is installed on the surface of an insulating substrate (polyimide resin, polyphenylene sulfide resin, etc.) and then covered with a coverlay, which is a heat-resistant resin film with an adhesive layer, for the purpose of insulating and protecting the circuit. , there are cases where molding is performed by press lamination through a release film. At this time, the release film requires not only release properties from printed wiring board materials and press plates, shape followability, and uniform formability, but also the property of transferring a matte appearance (low-gloss appearance) to the release target (matte appearance transferability). In addition, for transfer films that transfer functional layers such as an insulating layer, hard coat layer, and electromagnetic wave shield layer to the surface of a circuit board by heat pressing, the need for a film with a matte appearance and transferability is increasing.

Conventionally, processed products such as sand mat films, chemical mats, and coated mats are common as release films or transfer films having matte-like appearance transferability, but improvements have been desired to address issues such as increased costs and quality due to increased processing. As a method for solving these problems, a particle mixing film manufactured by extruding a large amount of particles together with a resin has been proposed (for example, Patent Documents 1 and 2). Additionally, a film having a sophisticated matte-like appearance with a resin layer coated on the surface has been proposed (for example, patent document 3).

Japanese Patent Publication No. 2016-97522 Japanese Patent Publication No. 2014-24341 Japanese Patent Publication No. 2005-24942

Although the films described in Patent Documents 1, 2, and 3 can lower gloss to some extent, it was difficult to achieve a low-gloss appearance that does not depend on the recently determined angle of incidence. The object of the present invention is to solve the problems of the prior art described above. In other words, the goal is to provide a film that can transfer a uniform, low-gloss appearance regardless of the angle of incidence when used as a transfer film.

In order to solve the above problems, the film of the present invention has the following structure.

(1) A film having a low gloss layer (A layer) having both a 60° glossiness (G ₆₀ ) and an 85° glossiness (G ₈₅ ) of 27 or less, wherein the A layer is in the surface layer on at least one side, and the 60° glossiness (G 85 ) is both 27 or less. A film whose glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) satisfy the equation (I) below.

0.1≤(G ₈₅ )/(G ₆₀₎ ≤3···(I)

(2) The film according to (1), wherein the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) of the low gloss layer (A layer) are both 10 or less.

(3) The film according to (1) or (2), wherein the variation in tensile breaking strength in a 20 cm x 30 cm range of the film is 20% or less.

(4) The film according to any one of (1) to (3), which has a base material layer on one side of the A layer.

(5) The film according to (4), wherein both the base layer and the A layer contain polyester resin as a main component.

(6) The film according to any one of (1) to (5), wherein the thickness of the layer A exceeds 3 μm and is 20 μm or less.

(7) The method according to any one of (1) to (6), wherein the A layer contains particles, the average particle diameter of the particles is 1.5 μm or more and 15 μm or less, and the content thereof makes the entire A layer 100% by mass. A film containing more than 18% by mass and less than or equal to 40% by mass.

(8) The method according to any one of (1) to (6), wherein the A layer contains particles, the average particle diameter of the particles is 3 ㎛ or more and 15 ㎛ or less, and the content thereof is 100% by mass of the entire A layer. A film comprising 18% by mass or more and 40% by mass or less.

(9) The film according to (7) or (8), wherein the circularity of the particles is 0.995 or less.

(10) The film according to (7) or (8), wherein the particle circularity is 0.995 or less and the bulkiness is 0.5 or more.

(11) The film according to any one of (1) to (10), wherein the 60° glossiness (G ₆₀ ) is less than 6.

(12) The film according to any one of (1) to (11), wherein the number of MIT bending fractures in at least one of the longitudinal direction (MD) and the transverse direction (TD) is 7,500 or more.

(13) The film according to any one of (1) to (12), wherein the thermal dimensional change rate in the longitudinal direction (MD) and the transverse direction (TD) in the range from 100°C to 150°C is 0.015%/°C or less.

(14) The film according to any one of (1) to (13), wherein the center line average roughness (SRa) of the surface of the layer A exceeds 1000 nm and is 3000 nm or less.

(15) The film according to any one of (1) to (14), wherein the thermal contraction rate at 150°C in the longitudinal direction (MD) and the transverse direction (TD) is 2% or less.

(16) The film according to any one of (1) to (15), wherein the curl height after heat treatment at 150°C for 10 minutes, measured by the following method, is 0 mm or more and 30 mm or less.

(Measurement method) The film is cut to a size of 100 mm in any one direction and 100 mm in a direction perpendicular to this direction to make a sample. After performing heat treatment by leaving the sample in a hot air circulation oven at 150°C for 10 minutes, it is placed on a glass plate, the amount of lifting at four corners in the vertical direction from the surface of the glass plate is measured, and the maximum height is taken as the curl height.

(17) The film according to any one of (1) to (16), wherein the surface free energy of the surface of the layer A is 44 mN/m or less.

(18) The film according to any one of (1) to (17), which is used for transfer purposes.

(19) A laminate formed by laminating a release layer on the surface of layer A of the film according to any one of (1) to (18).

(Effects of the Invention)

The film of the present invention has both 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) as low as 27 or less, and since the difference is controlled to a specific range, it exhibits an excellent low-gloss appearance regardless of the angle of incidence. , for example, when used as a transfer film, it has excellent transfer properties that give a low-gloss appearance to the transfer object. Therefore, for example, it can be suitably used as a transfer film with excellent transferability of a matte appearance in a circuit formation process. In addition, it is used for decoration of molded parts of building materials, automobile parts, electronic products such as smartphones, and home appliances, and is used as a surface for the purpose of imparting functionality such as sliding, air escape, and light diffusion to the functional layer. It can also be suitably used for shape transfer purposes.

Figure 1 is a schematic diagram showing how to obtain the volume diagram.

The film of the present invention is a film having a low gloss layer (A layer) with both 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) of 27 or less, and the A layer is a film in the surface layer of at least one side. . It is preferable that the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) are both 10 or less from the viewpoint of a low-gloss appearance, and most preferably less than 6. The resin used in the low-gloss layer is not particularly limited, but examples include polyesters such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyarylate, polyethylene, polypropylene, polyamide, Polyimide, polymethyl pentene, polyvinyl chloride, polystyrene, polymethyl methacrylate, polycarbonate, polyether ether ketone, polysulfone, polyether sulfone, fluororesin, polyetherimide, polyphenylene sulfide, polyurethane, and Cyclic olefin resins, etc. can be used. Among these, it is preferable to use polyester as the main component from the viewpoints of film handling, dimensional stability, and economic efficiency during production. In addition, in the present invention, the main component refers to containing 50% by mass or more relative to the entire layer.

In the present invention, polyester is a general term for polymers in which the main bond in the main chain is an ester bond, and can usually be obtained by subjecting a dicarboxylic acid component and a glycol component to a polycondensation reaction.

Dicarboxylic acid components used here include aromatics such as terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenoxyethanedicarboxylic acid, and 5-sodium sulfonedicarboxylic acid. Aliphatic dicarboxylic acids such as dicarboxylic acid, oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid, and fumaric acid, alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, and oxycarboxylic acids such as paraoxybenzoic acid. Each component such as these can be mentioned. In addition, as dicarboxylic acid ester derivative components, esterified products of the above dicarboxylic acid compounds, such as dimethyl terephthalate, diethyl terephthalate, 2-hydroxyethylmethyl terephthalate, dimethyl 2,6-naphthalenedicarboxylate, dimethyl isophthalate, and adip. Each component, such as dimethyl acid, diethyl maleate, and dimethyl dimer acid, is mentioned. In the polyester resin constituting the resin film of the present invention, the ratio of terephthalic acid and/or naphthalenedicarboxylic acid in all dicarboxylic acid components is preferably 85 mol% or more, more preferably 90 mol% or more in terms of heat resistance and productivity. It is preferable from

In addition, glycol components include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2, 2-dimethyl-1,3-propanediol, diethylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, 1,4-cyclohexanedimethanol, spiroglycol, neopentyl glycol, bisphenol A, bisphenol S, etc. Ingredients can be mentioned. Among them, from the viewpoint of ease of handling, the following components are preferably used: ethylene glycol, 1,4-butanediol, 1,3-propanediol, 1,4-cyclohexanedimethanol, neopentyl glycol, and diethylene glycol. In the polyester resin constituting the resin film of the present invention, it is preferable from the viewpoint of heat resistance and productivity that the ratio of ethylene glycol in all diol components is 65 mol% or more. Two or more types of these dicarboxylic acid components and glycol components may be used together.

It is preferable that the film of the present invention has a base material layer on one side of the A layer. It is preferable to have a film structure with a base material layer on one side of the A layer because it becomes easier to achieve both strength and low glossiness. The film of the present invention is preferably used in a two-layer structure of A layer/base layer, or a three-layer structure of A layer/base layer/A layer. In the present invention, when the A layer is disposed on the surface layer of both sides, the side with the lower 60° glossiness (G ₆₀ ) is called the A1 layer, and the side with the higher 60° glossiness (G ₆₀ ) is called the A2 layer.

In the case of the film of the present invention having a base layer on one side of layer A, the resin constituting the base layer is similar to the resin used in the low gloss layer (layer A), such as polyethylene terephthalate and polypropylene terephthalate. , polyester such as polybutylene terephthalate and polyethylene naphthalate, polyarylate, polyethylene, polypropylene, polyamide, polyimide, polymethyl pentene, polyvinyl chloride, polystyrene, polymethyl methacrylate, polycarbonate, poly Etheretherketone, polysulfone, polyethersulfone, fluororesin, polyetherimide, polyphenylene sulfide, polyurethane, and cyclic olefin resin can be used. Among these, it is preferable to use polyester as the main component from the viewpoints of film handling, dimensional stability, and economic efficiency during production.

In the film of the present invention, the thickness of the layer A is preferably greater than 3 μm and less than or equal to 20 μm. By making the thickness of the A layer thicker than 3 μm, the number of particles in the A layer increases sufficiently, and it becomes easy to control both the 60° glossiness and the 85° glossiness to 20 or less. In addition, even if the thickness of the layer A is thicker than 20 ㎛, the influence on glossiness is reduced, but the number of particles increases too much, which may reduce productivity. Therefore, it is preferable that the thickness of layer A is 20 μm or less. The thickness of layer A is more preferably 3.5 μm or more and 15 μm or less, and most preferably 4 μm or more and 10 μm or less.

In the film of the present invention, the low gloss layer (A layer) preferably contains particles. The particles contained in the A layer can be either inorganic particles or organic particles, and it is also possible to use inorganic particles and organic particles in combination. There is no particular limitation on the inorganic particles and/or organic particles used here, but for example, inorganic particles include silica, aluminum silicate, calcium carbonate, calcium phosphate, aluminum oxide, etc., and organic particles include styrene, silicon, acrylic acid, and metabolites. Particles containing acrylic acid, polyester, divinyl compound, etc. as constituents can be used. Among them, it is preferable to use inorganic particles such as wet and dry silica, colloidal silica, aluminum silicate, and particles containing styrene, silicon, acrylic acid, methacrylic acid, polyester, divinylbenzene, etc. as constituents. Silica and aluminum silicate are particularly preferably used from the viewpoint of low gloss appearance and economic efficiency. Additionally, two or more types of these externally added particles may be used in combination.

In the present invention, the inorganic particles and organic particles used do not include colorants for the purpose of coloring, such as dyes, inorganic pigments, and organic pigments. Specifically, blue pigments such as Bengala, molybdenum red, cadmium red, chrome orange, chrome vermilion, ultramarine blue, royal blue, cobalt blue, cerulean blue, chromium oxide, viridian, emerald green, cobalt green, yellow lead, cadmium yellow, Inorganic pigments such as yellow iron oxide, titanium yellow, manganese violet, mineral violet, titanium dioxide, barium sulfate, zinc oxide, zinc sulfate, carbon black, black iron oxide, condensed azo, phthalocyanine, quinacridone, dioxazine, isoindolinone, Organic pigments such as quinophthalone and anthraquinone do not apply to the inorganic particles and organic particles of the present invention.

In the present invention, in order to lower both the 60° glossiness (G60) and the 85° glossiness (G ₈₅ ) of the surface of the low gloss layer (layer A), particles with an average particle diameter of 1.5 ㎛ or more and 15 ㎛ or less are included in the A layer. It is preferable that it contains more than 18% by mass and 40% by mass or less, assuming that the entire layer A is 100% by mass. From the viewpoint of creating a low-gloss surface, it is more preferable that the average particle diameter of the particles in layer A is 3 μm or more and 15 μm or less, and most preferably it is 6 μm or more and 15 μm or less. Furthermore, the particle concentration in the A layer is more preferably 18 mass% to 40 mass%, with the entire A layer being 100 mass%, and most preferably exceeds 22 mass% and 40 mass% or less. In addition, the average particle diameter in the present invention refers to the number average diameter D expressed as D=ΣDi/N (Di: equivalent circular diameter of particle, N: number of particles).

In addition, in order to realize a low gloss surface independent of angle in the present invention, it is necessary that the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) satisfy the equation (I) below.

0.1≤(G ₈₅ )/(G ₆₀ )≤3···(I)

Satisfying equation (I) indicates that the difference between 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) is controlled to be small within a specific range, resulting in a uniform low-gloss surface that does not depend on the viewing angle. From the viewpoint of a uniform, low-gloss surface, it is more preferable if equation (II) is satisfied, and it is most preferable if equation (III) is satisfied.

0.1≤(G ₈₅ )/(G ₆₀ )≤2···(II)

0.1≤(G ₈₅ )/(G ₆₀ )≤1.5···(III)

In the present invention, the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) of the low gloss layer (A layer) are both set to 27 or less, and the method that satisfies the above equation (I) is not particularly limited. , the particles to be used include a method of using particles having a polyhedral shape, a method of using monodisperse particles, and a method of using particles of a polyhedral shape and monodisperse type. By applying polyhedral-shaped particles or monodisperse particles, a non-uniform shape can be given to the film surface, making it easy to achieve low gloss in all directions. The polyhedron shape in the present invention refers to a solid surrounded by a plurality of planes. The number of planes is not particularly limited as long as it is three or more, but from the viewpoint of imparting a non-uniform shape to the film surface, it is more preferable that it is tetrahedral or more, and it is most preferable that it is tetrahedral or more but octahedron or less. In addition, the polyhedron shape in the present invention may be one whose surface is formed by various polygons such as triangles, squares, and pentagons. In the film of the present invention, the particles contained in the low-gloss layer (layer A) preferably have a circularity (4π×area/peripheral length ² ) of 0.995 or less on the projection, as determined by the measurement method described later. More preferably, it is 0.990 or less. On the other hand, if the circularity is too low, if the film of the present invention is an oriented film, the direction of the particles may coincide with the stretching direction, making it difficult to form a shape with little direction dependence on the film surface. Therefore, the circularity should be 0.800 or more. desirable. In addition, in the film of the present invention, it is preferable that the volume of the particles contained in the low-gloss layer (A layer) is 0.5 or more as determined by the measurement method described later. When the film of the present invention is an oriented film, it is formed through a process of stretching the film. At that time, if the particles have a small volume (needle-shaped particles or plate-shaped particles), the direction of the particles coincides with the stretching direction, making it difficult to form a shape with less direction dependence on the film surface. By containing large-volume particles in the low-gloss layer (A layer), it becomes easy to give the film surface a shape with little direction dependence even if the film is formed through a stretching process. The volume degree is more preferably 0.6 or more, and even more preferably 0.7 or more. On the other hand, from the viewpoint of achieving low gloss without angle dependence by giving the film surface a non-uniform shape, the volume ratio is preferably 0.9 or less. In addition, in the present invention, monodisperse particles are particles that have almost no secondary aggregated particles and are dispersed in the polymer as primary particles, and when the film is observed with a transmission electron microscope, secondary agglomerates per 0.01 mm2 field of view. Indicates that the number of particles is 20 or less.

In the present invention, in order to form a low-gloss surface independent of angle and achieve both matte transferability and film strength, layer A with a thickness of 4 ㎛ or more and 10 ㎛ or less must have an average polyhedral particle diameter of 6 ㎛ or more and 15 ㎛ or less. A configuration containing 22% by mass or more and 40% by mass or less of particles of 100% by mass of the entire layer A is a very preferable embodiment.

From the viewpoint of improving film strength, the film of the present invention preferably has an MIT bending fracture count of 7500 or more in at least one of the longitudinal direction (MD) and the transverse direction (TD). By setting the number of MIT bending fractures to 7500 or more, the occurrence of tearing or cleavage when peeling the film after transfer can be suppressed. It is more preferable that the number of MIT bends is 7500 or more in both the longitudinal direction (MD) and the transverse direction (TD). The method of increasing the number of MIT bending fractures in at least one of the longitudinal direction (MD) and the transverse direction (TD) to 7,500 or more is not particularly limited, but for example, in the case of a biaxially stretched polyester film, layer A is applied before heat treatment. A method of performing stretching at a temperature equal to or higher than the crystallization temperature (Tcc) is preferably used. By applying the above conditions, it becomes possible to form fine oriented crystals before heat treatment and grow them by heat treatment, thereby reducing the number of lamellae that are considered to be the starting point of film tearing or cleavage.

The film of the present invention has a thermal dimensional change rate of 0.015%/°C or less in the longitudinal direction (MD) and transverse direction (TD) from 100°C to 150°C from the viewpoint of quality improvement in high-temperature processing such as heat pressing. It is desirable. By setting the thermal dimensional change rate in the above direction to 0.015%/°C or less, the occurrence of wrinkles due to expansion deformation during high-temperature processing can be suppressed. It is more preferable that the thermal dimensional change rate is 0.012%/℃ or less, and most preferably it is 0.009%/℃ or less. In the present invention, the method of reducing the thermal dimensional change rate in the range of 100°C to 150°C in the longitudinal direction (MD) and transverse direction (TD) to 0.015%/°C or less is not particularly limited, but for example, biaxially oriented poly When making an ester film, a method of lowering the temperature in stages after heat treatment and relaxing at each stage is preferably used.

From the viewpoint of transferability of the matte appearance of the film of the present invention, it is preferable that the center line average roughness SRa of the surface of layer A exceeds 1000 nm and is 3000 nm or less. If the center line average roughness SRa on the A-layer side is 1000 nm or less, the matte transferability may not be sufficient, and if it is set to be larger than 3000 nm, the strength of the film may decrease. From the viewpoint of matte transferability and film strength, it is more preferable that the center line average roughness SRa on the A layer side is 1100 nm or more and 2500 nm or less, and most preferably 1200 nm or more and 2000 nm or less. In the present invention, the method of adjusting the center line average roughness SRa on the A layer side from more than 1000 nm to 3000 nm or less is not particularly limited, but includes a method of adjusting the content of particles in the A layer, and a method of adjusting the content of particles in the A layer. Reducing voids can be cited as a preferable method. By reducing the voids around the particle, it becomes easier to form the shape of the particle on the surface, and it becomes easier to largely control the center line average roughness SRa from exceeding 1000 nm to 3000 nm or less. As a method of reducing voids around particles in the A layer, for example, both the base layer and the low gloss layer (A layer) are made of polyester, and in the case of a biaxially stretched polyester film, the low gloss layer (A layer) is stretched. A method of increasing tenacity, a method of reducing voids by treating at a high temperature in the heat treatment process after stretching described later, etc. are preferably used. The low gloss layer (layer A) preferably contains copolymerized polyethylene terephthalate resin, polypropylene terephthalate resin and/or its copolymer, and polybutylene terephthalate resin and/or its copolymer in order to increase stretchability.

From the viewpoint of dimensional stability of the film, the film of the present invention preferably has a thermal contraction rate of 2% or less in both the longitudinal direction (MD) and the transverse direction (TD) at 150°C. By controlling the thermal contraction rate at 150°C in the longitudinal direction (MD) and transverse direction (TD) to 2% or less, it is possible to suppress the occurrence of curls, wrinkles, etc. in various processing processes. In the present invention, in order to further increase dimensional stability, it is more preferable that the thermal contraction rate at 150°C in the longitudinal direction (MD) and transverse direction (TD) is 1.8% or less, and most preferably 1.5% or less.

From the viewpoint of handleability, the film of the present invention preferably has a curl height of 0 mm or more and 30 mm or less after heat treatment at 150°C for 10 minutes. In the present invention, the curl height after heat treatment at 150°C for 10 minutes means cutting a film into a size of 100 mm in any one direction and 100 mm in a direction perpendicular to that direction to make a sample, and blowing the sample through hot air circulation at 150°C. After performing heat treatment by leaving it in the oven for 10 minutes, it is placed on a glass plate, the amount of lifting at four corners in the direction perpendicular to the surface of the glass plate is measured, and the maximum height is calculated as the curl height. It is more preferable that the curl height is 0 mm or more and 25 mm or less, and it is most preferable that the curl height is 0 mm or more and 20 mm or less.

In the present invention, the method of reducing the heat shrinkage rate at 150°C in the longitudinal direction (MD) and the transverse direction (TD) to 2% or less, and the method of reducing the curl height after heat treatment at 150°C for 10 minutes to 0 mm or more and 30 mm or less, include: Although it is not particularly limited, an example is a method of adjusting the heat treatment conditions of the film after biaxial stretching. By setting the treatment temperature to a high temperature, orientation relaxation occurs and heat shrinkage tends to decrease. However, from the viewpoint of dimensional stability and film quality, the heat treatment temperature after biaxial stretching is preferably 220°C to 240°C, and 225°C to 240°C. It is more preferable, and it is most preferable if it is 230°C to 240°C. In addition, the heat treatment temperature of the film can be determined from the micro endothermic peak resulting from the heat history in the DSC curve when measured with a differential scanning calorimeter (DSC) at a temperature increase rate of 20°C/min in a nitrogen atmosphere, and the present invention In the film, the micro endothermic peak temperature is preferably 220 to 240°C.

Additionally, the preferred heat treatment time can be set arbitrarily between 5 and 60 seconds, but from the viewpoints of dimensional stability, film quality, and productivity, it is preferable to set it to 10 to 40 seconds, and more preferably 15 to 30 seconds. In addition, heat treatment can be performed while relaxing in the longitudinal direction and/or the width direction to reduce the thermal contraction rate. The relaxation rate (relaxation rate) when relaxing during heat treatment is preferably 1% or more. From the viewpoint of dimensional stability and productivity, it is preferable that it is 1% or more and 10% or less, and most preferably 1% or more and 5% or less.

In addition, a method of heat treatment under two or more stages is also highly desirable. After heat treatment at a high temperature of 220°C to 240°C, it is possible to further reduce the heat shrinkage rate by heat treatment while relaxing in the longitudinal direction and/or the width direction at a temperature lower than the heat treatment temperature. At this time, the heat treatment temperature in the second stage is preferably less than 120°C to 200°C, and more preferably 150°C to 180°C. In addition, as a method of setting the curl height after heat treatment at 150°C for 10 minutes to 0 mm or more and 30 mm or less, there is no difference in the cooling rate of the resin on the top and the opposite side of the cooling drum during resin extrusion, for example, on the cooling drum surface. A method of installing a cooling nip roll on the opposite side is also preferably used. In addition, when the film of the present invention has a film structure having the A layer on at least one side of the base layer, it is configured to have the A layer on both sides of the base layer, and even when it has the A layer on one side of the base layer, the base layer It is preferable that the resins of the and A layers have similar compositions.

The film of the present invention preferably has a variation in tensile breaking strength of 20% or less over a 20 cm x 30 cm range. By reducing the variation in tensile breaking strength, the handleability of the film is improved, and the occurrence of film tearing at locations where strength is weak during film transport or transfer peeling can be suppressed. In the present invention, the deviation in the tensile breaking strength of the film in the range of 20 cm Then, each 15 cm long sample was cut into 1 cm wide pieces in the width direction, and the breaking strength was measured and calculated by a tensile test for 40 strip-shaped samples of 15 cm long x 1 cm wide. It is more preferable that the deviation of the tensile breaking strength in the range of 20 cm x 30 cm of the film is 15% or less, and most preferably it is 0.1% or more and 10% or less.

A method of reducing the variation in tensile strength at break in the 20 cm x 30 cm range of the film of the present invention to 20% or less includes, for example, a method of improving the dispersibility of particles contained in the A layer. The dispersibility of the particles is improved and the particles exist uniformly in the A layer, thereby reducing the variation in tensile breaking strength. The method for improving the dispersibility of particles is not particularly limited, but for example, the particles are compounded with a resin that is highly compatible with the base resin constituting the A layer, and the particle compound raw material is alloy-extruded into the base resin to form the A layer. A method of forming, etc. may be mentioned. For example, when the base resin is polyethylene terephthalate, it is desirable to select polybutylene terephthalate, polypropylene terephthalate, etc. as the compound resin.

From the viewpoint of transferability, the film of the present invention preferably has a surface free energy of the A-layer surface of 44 mN/m or less. By setting the surface free energy to 44 mN/m or less, peelability from the transfer material is improved, making transfer and peeling easier and transferability improved. The surface free energy on the A-layer side is more preferably 40 mN/m or less, and most preferably 35 mN/m or less. On the other hand, from the viewpoint of uniform applicability of the transfer material and adhesion during processing, it is preferable that it is 20 mN/m or more.

The method for adjusting the surface free energy of the present invention to the above-mentioned range is not particularly limited, but includes a method of containing a mold release agent such as a silicone compound, a wax compound, or a fluorine-based compound in the A layer.

In the present invention, from the viewpoint of heat resistance during heating, it is preferable that layer A be a layer containing a melamine resin and a mold release agent (hereinafter, the layer containing a mold release agent may be referred to as a mold release layer). From the viewpoint of heat resistance and mold release stability, the content of melamine resin in layer A is preferably 50% by mass or more.

Melamine resins include melamine formaldehyde resins such as melamine formaldehyde resin, methylated melamine formaldehyde resin, butylated melamine formaldehyde resin, etherified melamine formaldehyde resin, and epoxy-modified melamine formaldehyde resin, urea melamine resin, and acrylic melamine resin. However, melamine formaldehyde resin is preferable, and methylated melamine formaldehyde resin is particularly preferably used because it has appropriate release properties. In addition, the layer A of the present invention preferably contains a binder resin in addition to a binder resin and a mold release agent from the viewpoint of film forming properties and stretching followability. As the binder resin, polyester resin, acrylic resin, and urethane resin are preferably used, and acrylic resin is especially preferably used. Acrylic resins include homopolymers or copolymers of (meth)acrylic acid alkyl esters, and (meth)acrylic acid ester copolymers having a curable functional group at the side chain and/or main chain terminal, and the curable functional group includes hydroxyl group, carboxyl group, epoxy group, and amino group. etc. can be mentioned. Among them, an acrylic monomer copolymer obtained by copolymerizing an acrylic monomer and an acrylic acid ester having a curable functional group at the side chain and/or main chain terminal is preferable. In addition, examples of the release agent contained in layer A of the present invention include fluorine compounds, long-chain alkyl compounds, and wax compounds. These mold release agents may be used individually, or multiple types may be used.

Fluorine compounds that can be used in the present invention are compounds that contain a fluorine atom. Examples include perfluoroalkyl group-containing compounds, polymers of olefin compounds containing fluorine atoms, and aromatic fluorine compounds such as fluorobenzene. When the release film of the present invention is used for molding transfer film applications, etc., a high heat load is applied during transfer, so considering heat resistance and contamination, it is preferable that the fluorine compound is a polymer compound.

A long-chain alkyl compound is a compound having a straight-chain or branched alkyl group having 6 or more carbon atoms, particularly preferably 8 or more carbon atoms. Specific examples include, but are not limited to, polyvinyl resins containing long-chain alkyl groups, acrylic resins containing long-chain alkyl groups, polyester resins containing long-chain alkyl groups, amine compounds containing long-chain alkyl groups, ether compounds containing long-chain alkyl groups, quaternary ammonium salts containing long-chain alkyl groups, etc. . If the long-chain alkyl compound is a high molecular compound, it is preferable because it can suppress the transfer of components derived from the A layer to the surface of the other substrate to which the release film is bonded.

The wax that can be used in the present invention is a wax selected from natural waxes, synthetic waxes, and waxes blended thereof. Natural waxes include plant wax, animal wax, mineral wax, and petroleum wax. Examples of plant-based waxes include candelilla wax, carnauba wax, rice wax, wood wax, and jojoba oil. Animal waxes include beeswax, lanolin, and spermaceti. Examples of mineral waxes include montan wax, ozokerite, and ceresin. Petroleum waxes include paraffin wax, microcrystalline wax, and petrolatum. Examples of synthetic waxes include synthetic hydrocarbons, denatured waxes, hydrogenated waxes, fatty acids, acid amides, amines, imides, esters, and ketones. Famous synthetic hydrocarbons include Fischer-Tropsch wax (aka Sazoyl wax) and polyethylene wax, but in addition to these, the following polymers that are low molecular weight polymers (specifically, polymers with a viscosity average molecular weight of 500 to 20,000) are also included. That is, there are polypropylene, ethylene-acrylic acid copolymer, polyethylene glycol, polypropylene glycol, and block or graft combinations of polyethylene glycol and polypropylene glycol. Modified waxes include montan wax derivatives, paraffin wax derivatives, and microcrystalline wax derivatives. The derivative herein is a compound obtained by any of purification, oxidation, esterification, saponification, or a combination thereof. Hydrogenated waxes include hydrogenated castor oil and hydrogenated castor oil derivatives.

By dispersing these release agents uniformly on the surface of layer A, the adhesion and peeling force with the release layer to be laminated and peeled off from layer A can be kept in an appropriate range. The use of a long-chain alkyl compound as a mold release agent is preferable for use in the present invention because the peeling force can be adjusted over a wide range.

Next, examples of specific manufacturing methods for the film of the present invention will be described, but the present invention is not to be construed as being limited to these examples.

When the film of the present invention consists of a base layer and a low-gloss layer (A layer), and each layer uses a polyester resin, each resin is supplied to a different extruder and melt-extruded. At this time, it is desirable to control the resin temperature between 255℃ and 295℃. Next, foreign substances are removed and the extrusion amount is equalized through a filter or a gear pump, and the sheet is co-extruded from the T die onto a cooling drum to obtain a laminated sheet. At that time, the electrostatic application method uses an electrode applied with high voltage to electrostatically adhere the cooling drum to the resin, the casting method forms 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 the polyester resin~( The sheet-shaped polymer is brought into close contact with the casting drum and cooled and solidified by a method of adhering the extruded polymer at a glass transition point of -20°C or a combination of these methods. Among these casting methods, when using polyester, electrostatic application is preferable from the viewpoint of productivity and flatness, and from the viewpoint of suppressing curl during heating, a method of installing a cooling nip roll on the side opposite to the cooling drum is also preferable. It is used. The film of the present invention is preferably a biaxially oriented film from the viewpoint of heat resistance and dimensional stability. Biaxially oriented films are produced by a sequential biaxial stretching method in which an 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, or by stretching the film in the longitudinal or width directions. It can be obtained by performing stretching using a simultaneous biaxial stretching method in which stretching is performed almost simultaneously.

The draw ratio in this stretching method is 2.8 times to 3.4 times, more preferably 2.9 times to 3.3 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 70°C or higher and 90°C or lower. Additionally, the stretch ratio in the width direction is preferably 2.8 times or more and 3.8 times or less, and more preferably 3 times or more and 3.6 times or less. The stretching speed in the width direction is preferably 1,000%/min or more and 200,000%/min or less. In addition, the stretching temperature in the width direction is preferably 70°C or higher and 180°C or lower, but from the viewpoint of improving film strength, it is more preferable that the stretching temperature is higher than the crystallization temperature of the A layer. Additionally, the film is heat treated after biaxial stretching. Heat treatment can be performed by any conventionally known method, such as on a roll heated in an oven. This heat treatment is performed at a temperature of 120°C or higher and below the crystal melting peak temperature of polyester, but also from the viewpoint of reducing voids around the particles in the A layer and from the viewpoint of controlling the heat shrinkage rate at 150°C to 2% or less. The heat treatment temperature is preferably 220°C or higher. Additionally, from the viewpoint of keeping the thermal dimensional change rate in the range from 100°C to 150°C to 0.015%/°C or less, it is preferable to perform the relaxation treatment while gradually lowering the temperature after the heat treatment. More specifically, relaxation heat treatment with a relaxation rate of 0.5% or more is performed at the maximum temperature of heat treatment (Tmax), and then one or more stages of relaxation heat treatment with a relaxation rate of 0.5% or more are performed at a temperature of Tmax -50℃ or more and Tmax -5℃ or less. desirable. Relaxation heat treatment at Tmax -50°C or higher and Tmax -5°C or lower is preferably performed at least once in each temperature range of Tmax -25°C or higher and Tmax -5°C or lower and Tmax -50°C or higher and Tmax -25 or lower. do. The relaxation heat treatment may be performed in either the longitudinal direction or the width direction. However, in the case of biaxial stretching by sequential biaxial stretching, it is preferable from the viewpoint of productivity to continuously perform the relaxation heat treatment after stretching in the second stretching direction.

In addition, in order to ensure stable release properties, the film of the present invention is also preferably a laminate formed by providing a release layer on the surface of layer A of the film. The method of installing the release layer is not particularly limited, but includes an in-line coating method. A method of installing a coating layer in-line within the film manufacturing process involves uniformly applying a coating layer composition dispersed in water onto at least a uniaxially stretched film using a metal ring bar or gravure roll, and drying the coating while stretching. This method is preferable, and the thickness of the release layer at that time is preferably 0.02 μm or more and 0.1 μm or less. Additionally, various additives such as antioxidants, heat stabilizers, ultraviolet absorbers, infrared absorbers, pigments, dyes, organic or inorganic particles, antistatic agents, nucleating agents, etc. may be added to the release layer.

The film of the present invention has both 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) as low as 20 or less, and the difference is controlled to be small within a specific range, so it exhibits an excellent low-gloss appearance regardless of the angle of incidence. , When used as a transfer film, the transferability of the low-gloss appearance is excellent. Therefore, it can be suitably used as a transfer film with excellent transferability of a matte appearance in the circuit formation process.

(Example)

(1) Composition of polyester

The polyester resin and film can be dissolved in hexafluoroisopropanol (HFIP), and the content of each monomer residue or by-product diethylene glycol can be quantified using ¹ H-NMR and ¹³ C-NMR. In the case of a laminated film, the components constituting each layer can be sampled and evaluated by removing each layer of the film according to the laminated thickness. 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 of polyester

The intrinsic viscosity of the polyester resin and film was measured at 25°C by dissolving polyester in orthochlorophenol and using an Oswald viscometer. In the case of a laminated film, the intrinsic viscosity of each layer alone can be evaluated by removing each layer of the film according to the lamination thickness.

(3) Film thickness

Film thickness was measured using a dial gauge.

(4) Each layer thickness

The film was embedded in epoxy resin, and a 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.

(5) Average particle diameter of particles

The resin is removed from the film by a plasma low-temperature incineration treatment (PR-503 type manufactured by Yamato Scientific Co., Ltd.) to expose the particles. This was observed with a transmission electron microscope (TEM H7100, manufactured by Hitachi, Ltd.), and the image of the particle (light intensity generated by the particle) was attached to an image analyzer (QTM900, manufactured by Cambridge Instrument Co., Ltd.), and the observation point was changed to determine the particle size. The following numerical processing was performed on 100 numbers, and the number average diameter D obtained thereby was called the average particle diameter.

D=ΣDi/N

Here, Di is the equivalent circular diameter of the particle, and N is the number of particles.

(6) Shape and circularity of particles

In the same manner as (5), the image of the particles was observed. In addition, the circularity was calculated by the following formula, and the average value of 100 particles was taken as the circularity of the present invention.

Circularity=4π×area/peripheral length ²

(7) Shape and volume of particles

A film cross section parallel to the film longitudinal direction and perpendicular to the film thickness direction and a film cross section parallel to the film width direction and perpendicular to the film thickness direction were cut with a microtome and observed by the method described in (5). The length at which the ends of a particle are longest in a particle in a cross section is L1, and in calculating L1, the length at which the ends of a particle are longest in the direction perpendicular to the line segment connecting the ends of the particle is called L2 ( Figure 1). The volume diagram is calculated by calculating L2/L1 for each of the film cross-sections parallel to the film length direction and perpendicular to the film thickness direction and the film cross-sections parallel to the film width direction and perpendicular to the film thickness direction, and taking the average of 100 each. Saved.

(8) Particle content

1 g of polymer was added to 200 ml of 1N-KOH methanol solution and heated to reflux to dissolve the polymer. 200 ml of water was added to the solution where dissolution was completed, and the liquid was then passed through a centrifuge to settle the particles to remove the supernatant. Additional water was added to the particles, and washing and centrifugation were repeated twice. The particles obtained in this way were dried and their mass was measured to calculate the particle content.

(9) Glossiness

According to the method specified in JIS-Z-8741 (1997), 60° specular gloss and 85° specular gloss were measured using a digital variable angle glossmeter UGV-5D manufactured by Suga Test Instruments Co., Ltd. N = 3 each. was measured, and the average values were referred to as 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) of the present invention.

(10) Number of MIT bends

The polyester film was cut into a strip of 15 mm in width and 100 mm in length to serve as a sample. Using an MIT tear resistance tester (manufactured by MYS-TESTER Company Limited), the film was measured three times in the longitudinal and width directions, and the average value was calculated.

·Tip: R0.38㎜

·Bending angle: 135° left and right

·Bending speed: 175 round trips/minute

·Load: 9.8N

(11) Center line average roughness SRa

A sample was cut to the dimensions of 4.0 cm in length x 3.5 cm in width, and the surface shape of the film was measured under the following conditions in accordance with JIS B0601-1994 using a high-precision fine shape measuring device (3D surface roughness meter) using the stylus method. .

・Measurement device: 3D fine shape measuring device (Kosaka Laboratory Ltd., type ET-4000A)

·Analysis device: 3D surface roughness analysis system (TDA-31 type)

·Stylus: tip radius 0.5㎛R, diameter 2㎛, made of diamond

·Accumulation pressure: 100μN

·Measurement direction: average after measuring once each in the film length direction and film width direction

·X Measurement Length: 1.0mm

·X feed speed: 0.1 mm/s (measurement speed)

Y feed pitch: 5㎛ (measurement interval)

· Number of Y lines: 81 (number of measurements)

·Z magnification: 20x (vertical magnification)

·Low range cutoff: 0.20mm

·High-range cutoff: R+W㎜ (roughness cutoff value) R+W means no cutoff.

·Filter method: Gaussian space type

·Leveling: Yes (slope correction)

·Reference area: 1㎟

Measurements were performed under the above conditions, and then the center line average roughness SRa was calculated using an analysis system.

(12) Thermal dimensional change rate in the range from 100℃ to 150℃

A sample was cut into a rectangle of 50 mm in length x 4 mm in width so that the longitudinal direction (MD) and the transverse direction (TD) were each longitudinal, and the following was used using a thermomechanical analysis device (TMA EXSTAR6000, manufactured by Seiko Instruments Inc.) The temperature was raised under the conditions, and the rate of thermal dimensional change from 100°C to 150°C was measured.

Test length: 15 mm, load: 19.6 mN, temperature increase rate: 10°C/min,

Measurement temperature range: 30~200℃

Thermal dimensional change rate (%) in the range from 100°C to 150°C = [{Film length at 150°C (mm) - Film length at 100°C (mm)}/Film length at 100°C (mm)] 100

In addition, the measurement was performed on 5 samples of each film in the longitudinal direction and the width direction, and evaluation was performed using the average value.

(13) 150℃ heat shrinkage rate

A sample was cut into a rectangle of 150 mm in length x 10 mm in width so that the longitudinal direction (MD) and the transverse direction (TD) were each longitudinal. Marking lines were drawn on the sample at intervals of 100 mm, a 3 g weight was hung, and heat treatment was performed by placing it in a hot air oven heated to 150°C for 30 minutes. The distance between the gauge lines after heat treatment was measured, and the heat contraction rate was calculated from the change in the distance between the gauge lines before and after heating using the following formula. The measurement was performed on 5 samples of each film in the longitudinal and width directions, and evaluation was performed using the average value.

Heat shrinkage rate (%) = {(distance between marked lines before heat treatment) - (distance between marked lines after heat treatment)}/(distance between marked lines before heat treatment) × 100

(14) Curl height after heat treatment at 150℃ for 10 minutes

The film is cut to a size of 100 mm in any one direction and 100 mm in a direction perpendicular to this direction to make a sample. The sample was heat treated by leaving it in a hot air circulation oven at 150°C for 10 minutes and then placed on a glass plate. The amount of lifting at four corners in the vertical direction from the surface of the glass plate was measured, and the maximum height was taken as the curl height.

(15) Variation in tensile breaking strength in the range of 20 cm × 30 cm of film

The film was cut into 20 cm wide x 30 cm long samples at random positions, divided into two 15 cm long samples, and each 15 cm long sample was cut into 1 cm wide pieces in the width direction, making 15 cm long x wide. Create 40 strip-shaped samples of 1 cm. For the above sample, a tensile test was performed using a tensile tester (TENSILON UCT-100 manufactured by ORIENTEC CORPORATION) with an initial tensile chuck distance of 50 mm and a tensile speed of 300 mm/min, and the strength (tensile strength) when the film was broken was measured. Breaking strength) was measured and the deviation was obtained as follows.

Deviation of tensile breaking strength (%)={(maximum value-minimum value)/average value}×100

(16) Surface free energy

Four types of measurement liquids were used: water, ethylene glycol, formamide, and diiodomethane, and the static contact angle of each liquid with respect to the film surface was measured using a contact angle meter (CA-D type manufactured by Kyowa Interface Science Co., Ltd.). saved. Each liquid was measured five times, and the average contact angle (θ) and each component of the surface tension of the measured liquid (j) were substituted into the equations below to create a simultaneous equation consisting of four equations: γ ^L , γ ⁺ , γ ^- Solved about this.

(γ ^L γj ^L ) ^1/2 +2(γ ⁺ γj ^- ) ^1/2 +2(γj ⁺ γ ^- ) ^1/2

=(1+cosθ)[γj ^L +2(γj ⁺ γj ^- ) ^1/2 ]/2

However, γ=γ ^L +2(γ ⁺ γ ^- ) ^1/2

γj=γj ^L +2(γj ⁺ γj ^- ) ^1/2

Here, γ, γ ^L , γ ⁺ , and γ ^- are the surface free energy of the film surface, long-range force term, Lewis acid parameter, and Lewis base parameter, respectively, and γj, γj ^L , γj ⁺ , and γj ^- are the measurement liquid used, respectively. The surface free energy, long-range force term, Lewis acid parameter, and Lewis base parameter are shown. In addition, the surface tension of each liquid used here was the value proposed by Oss ("fundamentals of Adhesion", LH Lee (Ed.), p153, Plenumess, New York (1991)).

(17) Peelability

The film was cut into 100 mm in length x 100 mm in width and used. The coating composition for forming the hard coat layer below was applied using a slot die coater with the flow rate controlled so that the thickness after drying was 5㎛, dried at 100°C for 1 minute to remove the solvent, and the laminate with the hard coat layer was obtained. got it

The obtained film/hard coat layer laminate was heated to 160°C for both the upper and lower mold temperatures using a press machine, and an aluminum plate with a thickness of 0.2 mm/a polyimide film with a thickness of 0.125 mm (DU PONT-TORAY CO., DU PONT-TORAY CO., LTD. LTD. KAPTON 500H/V) / Laminate / 0.125 mm thick polyimide film (DU PONT-TORAY CO., LTD. KAPTON 500H/V) / 0.2 mm thick aluminum plate composition under the condition of 1.5 MPa. Heat pressing was performed for 1 hour. After heat pressing, the laminate is taken out, and ultraviolet rays of 300 mJ/cm2 are irradiated from the laminate side using a high-pressure mercury lamp to cure the hard coat layer to obtain a sample. This sample was subjected to a peeling test at the interface between the film and the hard coat layer, and peelability was evaluated based on the following criteria. Additionally, when a release layer was provided on the film, a peeling test was performed at the interface between the film/release layer and the hard coat layer. The peeling test was performed 5 times and evaluated according to the following evaluation criteria.

(Paint composition for forming hard coat layer)

The following materials were mixed and diluted using methyl ethyl ketone to obtain a coating composition for forming a hard coat layer with a solid content concentration of 40% by mass.

30 parts by mass of toluene

25 parts by mass of multifunctional urethane acrylate

(KRM8655 manufactured by DAICEL-ALLNEX LTD.)

25 parts by mass of pentaerythritol triacrylate mixture

(PET30 manufactured by Nippon Kayaku Co., Ltd.)

1 part by mass of multifunctional silicone acrylate

(EBECRYL1360 manufactured by DAICEL-ALLNEX LTD.)

3 parts by mass of photopolymerization initiator

(IRGACURE184 manufactured by Ciba Specialty Chemicals Inc.)

(Evaluation standard)

A: Peeling is possible without resistance, and no tearing of the film occurred (in all 5 peeling tests).

B: Resistance was felt during peeling, but peeling was possible, and no tearing of the film occurred (in all five peeling tests).

C: Although peeling was possible (in any one of the five peeling tests), film tearing occurred during peeling.

D: It was not possible to peel (in all 5 peeling tests).

(18) Curlability after heat pressing

In the same manner as in (17), the laminate after heat pressing was placed on a glass plate, the amount of lifting at four corners in the direction perpendicular to the glass plate surface was measured, and the maximum height was taken as the curl height.

A: Curl height is between 0mm and less than 10mm

B: Curl height is 10mm or more but less than 20mm

C: Curl height greater than 20 mm but less than 30 mm

D: Curl height is 30 mm or more

(18) Transferability and uniform appearance of matte appearance

The glossiness was measured on the peeled surface side of the hard coat layer obtained by the method in (17), and the average value was evaluated according to the following criteria.

(Transferability of matte appearance)

A: Both 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) are 10 or less.

B: One side of the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) was 10 or less, but the other side was greater than 10 and less than 27.

C: Both 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) were 10 to 27.

D: At least one of the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) was greater than 27.

(Matte-like appearance and uniform appearance)

A: 0.1≤(G ₈₅ )/(G ₆₀ )≤1.5

B: 1.5<(G ₈₅ )/(G ₆₀ )≤2

C: 2.0<(G ₈₅ )/(G ₆₀ )≤3

D: 0.1>(G ₈₅ )/(G ₆₀ ) or (G ₈₅ )/(G ₆₀ )>3

(19) Warrior Dignity

The appearance of the peeled surface side of the hard coat layer obtained by the method (17) was observed with the naked eye, and evaluated based on the following criteria.

A: No wrinkles are visible.

B: Does not apply to A, and no more than 2 wrinkles occur

C: Does not correspond to A or B, and the number of wrinkles is less than 5

D: Does not apply to any of A, B, or C

(Manufacture of polyester)

The polyester resin used for film unveiling was prepared as follows.

(polyester A)

Polyethylene terephthalate resin (intrinsic viscosity 0.75) containing 100 mol% of terephthalic acid as a dicarboxylic acid component and 100 mol% of ethylene glycol as a glycol component.

(polyester B)

A copolymerized polyethylene terephthalate resin in which 20 mol% of isophthalic acid is copolymerized with respect to the dicarboxylic acid component (intrinsic viscosity 0.8).

(polyester C)

A polybutylene terephthalate resin (intrinsic viscosity 1.2) containing 100 mol% of terephthalic acid as a dicarboxylic acid component and 100 mol% of 1,4-butanediol as a glycol component.

(polyester D)

“HYTREL (registered trademark)” 7247, manufactured by DU PONT-TORAY CO., LTD.

(Particle Master E)

A polyethylene terephthalate particle master containing hexahedron-shaped aluminum silicate particles with an average particle diameter of 6 μm in polyester A at a particle concentration of 30% by mass (intrinsic viscosity 0.7).

(Particle Master F)

A polyethylene terephthalate particle master (intrinsic viscosity 0.7) containing aluminum silicate particles with an average particle diameter of 7.5 μm and a hexahedral shape in polyester A at a particle concentration of 30% by mass.

(Particle Master G)

A polyethylene terephthalate particle master containing hexahedral aluminum silicate particles with an average particle diameter of 10 μm in polyester A at a particle concentration of 30% by mass (intrinsic viscosity 0.7).

(Particle Master H)

A polyethylene terephthalate particle master containing octahedron-shaped aluminum silicate particles with an average particle diameter of 7.5 μm in polyester A at a particle concentration of 30% by mass (intrinsic viscosity 0.7).

(Particle Master I)

A polyethylene terephthalate particle master containing spherical aluminum silicate particles with an average particle diameter of 5 μm in polyester A at a particle concentration of 30% by mass (intrinsic viscosity 0.7).

(Particle Master J)

A polyethylene terephthalate particle master containing spherical aluminum silicate particles with an average particle diameter of 7.5 μm in polyester A at a particle concentration of 30% by mass (intrinsic viscosity 0.7).

(Particle Master K)

A polyethylene terephthalate particle master containing hexahedron-shaped aluminum silicate particles with an average particle diameter of 6 μm in polyester C at a particle concentration of 30% by mass (intrinsic viscosity 0.7).

(Particle Master L)

A polyethylene terephthalate particle master containing hexahedron-shaped aluminum silicate particles with an average particle diameter of 7.5 μm in polyester C at a particle concentration of 30% by mass (intrinsic viscosity 0.7).

(Particle Master M)

A polyethylene terephthalate particle master containing hexahedral aluminum silicate particles with an average particle diameter of 10 μm in polyester C at a particle concentration of 30% by mass (intrinsic viscosity 0.7).

(Particle Master N)

A polyethylene terephthalate particle master containing octahedron-shaped aluminum silicate particles with an average particle diameter of 7.5 μm in polyester C at a particle concentration of 30% by mass (intrinsic viscosity 0.7).

(Particle Master O)

A polyethylene terephthalate particle master containing spherical aluminum silicate particles with an average particle diameter of 5 μm in polyester C at a particle concentration of 30% by mass (intrinsic viscosity 0.7).

(Particle Master P)

A polyethylene terephthalate particle master containing spherical aluminum silicate particles with an average particle diameter of 7.5 μm in polyester C at a particle concentration of 30% by mass (intrinsic viscosity 0.7).

(Particle Master Q)

A polyethylene terephthalate particle master (intrinsic viscosity 0.7) containing alumina particles with an average particle diameter of 6 μm and an average thickness of 0.10 μm in polyester C at a particle concentration of 30% by mass.

(Solution for forming release layer (water dispersion))

The crosslinking agent shown below: binder resin: release agent: particles were mixed at a mass ratio of 60:23:17, respectively, and the solid content was diluted with pure water to adjust the mass ratio to 1%.

Cross-linking agent: Cross-linking agent resin of methylated melamine/urea copolymerization (“NIKALAC” (registered trademark) “MW12LF” manufactured by SANWA CHEMICAL CO., LTD.)

Binder Resin I: Acrylic monomer copolymer (manufactured by NIPPON CARBIDE INDUSTRIES CO., INC.)

· Release agent: 80.0 g of CF ₃ (CF ₂ ) _n CH ₂ CH ₂ OCOCH = CH ₂ (n = 5 to 11, average of n = 9), an acrylate containing a perfluoroalkyl group, in a glass reaction vessel, acetoacetoxyethyl. 20.0 g of methacrylate, 0.8 g of dodecyl mercaptan, 354.7 g of deoxygenated pure water, 40.0 g of acetone, 1.0 g of C ₁₆ H ₃₃ N(CH ₃ ) ₃ Cl, and C ₈ H ₁₇ C ₆ H ₄ O(CH ₂ A copolymer emulsion obtained by adding 3.0 g of CH ₂ O) _n H (n=8), adding 0.5 g of azobisisobutylamidine dihydrochloride, and copolymerizing the mixture at 60°C for 10 hours while stirring in a nitrogen atmosphere.

· Particles: An aqueous dispersion obtained by diluting silica particles ("SNOWTEX" (registered trademark) MP2040, manufactured by Nissan Chemical Corporation) with an average particle diameter of 170 nm with pure water so that the solid content concentration is 40% by mass.

(Example 1)

Raw materials are supplied to each extruder so that the composition and stacking ratio are as shown in the table, the extruder cylinder temperature is set to 270°C, the single tube temperature is set to 275°C, and the stopper temperature is set to 280°C. The resin temperature is set at 280°C to 25°C using a T die. It was discharged in the form of a sheet on a cooling drum whose temperature was controlled. At that time, electrostatic application was applied using a wire-like electrode with a diameter of 0.1 mm, and the sheet was brought into close contact with the cooling drum. Additionally, a cooling nip roll temperature-controlled at 25°C was installed on the opposite side of the cooling drum to obtain an unstretched sheet. Next, it was stretched 3.1 times in the longitudinal direction at a stretching temperature of 85°C, after which corona discharge treatment was performed, and a release layer forming solution (aqueous dispersion) was applied using a metal ring bar so that the wet thickness was 13.5 ㎛. It was stretched in the width direction in a tenter-type transverse stretching machine at a stretching temperature of 100°C and a stretching ratio of 3.3 times. Afterwards, heat treatment was performed at 235°C for 15 seconds in a tenter, and then heat treatment was performed at 175°C for 10 seconds with 3.5% relaxation in the width direction, to obtain a film with a film thickness of 50 μm (the surface of the low gloss layer (A layer) was A1. surface, the surface on the base layer side was called B-side).

(Example 2)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Example 3)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Example 4)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Example 5)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Example 6)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Example 7)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Example 8)

The composition was as shown in the table, and after stretching in the width direction, a film with a thickness of 50 μm was obtained in the same manner as in Example 2, except that it was heat treated for 30 seconds at 225°C while relaxing 1% in the width direction.

(Example 9)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Example 10)

The composition is as shown in the table, and when the sheet is extruded on the cooling drum by an extruder, an unstretched sheet is obtained without installing a cooling nip roll on the side opposite to the cooling drum. After stretching in the hand direction, corona discharge treatment and mold release layer application are performed. A film with a film thickness of 50 μm was obtained in the same manner as in Example 4 except that it was not carried out.

(Example 11)

The composition was as shown in the table, and a film with a film thickness of 50 μm was obtained in the same manner as in Example 5 except that it had a three-layer structure of A layer/base layer/A layer.

(Example 12)

The composition was as shown in the table, and a film with a film thickness of 50 μm was obtained in the same manner as in Example 5 except that it had a three-layer structure of A layer/base layer/A layer.

(Example 13)

The composition was as shown in the table, and a film with a film thickness of 38 μm was obtained in the same manner as in Example 5 except that it had a three-layer structure of A layer/base layer/A layer.

(Example 14)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Example 15)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Example 16)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 5, except that corona discharge treatment and release layer were not applied after longitudinal stretching.

(Example 17)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was changed as shown in the table and the transverse stretching temperature was changed to 140°C.

(Example 18)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was changed as shown in the table and the transverse stretching temperature was changed to 140°C.

(Example 19)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was changed as shown in the table.

(Example 20)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was changed as shown in the table.

(Example 21)

The composition was changed as shown in the table, and the film thickness was 50 ㎛ in the same manner as in Example 1, except that after stretching in the width direction, relaxation heat treatment in the width direction was performed under the conditions of 2.0% at 235 ° C. and 1.5% at 210 ° C. for 5 seconds each. obtained a film of

(Example 22)

The composition was changed as shown in the table, and after stretching in the width direction, relaxation heat treatment in the width direction was performed under the conditions of 1.5% at 235°C, 1.0% at 215°C, and 1.0% at 200°C for 5 seconds each, as in Example 1. In the same manner, a film with a film thickness of 50 μm was obtained.

(Example 23)

The composition was changed as shown in the table, and after stretching in the width direction, a relaxation heat treatment in the width direction was performed at 240°C at 3.5% for 15 seconds in the same manner as in Example 1 to obtain a film with a film thickness of 50 μm.

(Example 24)

The composition was changed as shown in the table, and the film thickness was 50 ㎛ in the same manner as in Example 1, except that after stretching in the width direction, relaxation heat treatment in the width direction was performed under the conditions of 2.0% at 235 ° C. and 1.5% at 210 ° C. for 5 seconds each. obtained a film of

(Example 25)

The composition was changed as shown in the table, and after stretching in the width direction, relaxation heat treatment in the width direction was performed under the conditions of 1.5% at 235°C, 1.0% at 215°C, and 1.0% at 200°C for 5 seconds each, as in Example 1. In the same manner, a film with a film thickness of 50 μm was obtained.

(Comparative Example 1)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Comparative Example 2)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Comparative Example 3)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Comparative Example 4)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Comparative Example 5)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

(Comparative Example 6)

The composition was as shown in the table, and a film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the stretching ratio in the width direction was 3.8 times.

(Comparative Example 7)

A film with a film thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table.

The film of the present invention has both 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) as low as 27 or less, and the difference is controlled to be small within a specific range, so it exhibits an excellent low-gloss appearance regardless of the angle of incidence. , When used as a transfer film, the transferability of the low-gloss appearance is excellent. Therefore, for example, it can be suitably used as a transfer film with excellent transferability of a matte appearance in a circuit formation process. In addition, it is used for decorating molded parts of building materials, electronic products such as automobile parts and smartphones, and home appliances, and for transferring surface shapes for the purpose of imparting functionality such as sliding, air escape, and light diffusion to the functional layer. It can also be used suitably.

Claims (19)

A film having a low gloss layer (A layer) with both a 60° glossiness (G ₆₀ ) and an 85° glossiness (G ₈₅ ) of 27 or less,
The A layer is on at least one surface layer, the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) satisfy the following equation (I), and a base layer is provided on one side of the A layer. A biaxially oriented film in which both the base material layer and the A layer each contain 50% by mass or more of polyester resin relative to the entire layer, and both the base material layer and the A layer are biaxially oriented.
0.1≤(G ₈₅ )/(G ₆₀ )≤3···(I) According to claim 1,
A film in which both the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) of the low gloss layer (A layer) are 10 or less. The method of claim 1 or 2,
A film in which the variation in tensile breaking strength in the 20 cm x 30 cm range of the film is 20% or less. The method of claim 1 or 2,
A film wherein the thickness of the A layer exceeds 3 ㎛ and is 20 ㎛ or less. The method of claim 1 or 2,
A film in which the layer A contains particles, and the circularity of the particles is 0.995 or less. The method of claim 1 or 2,
A film wherein the layer A contains particles, and the particles are inorganic particles. The method of claim 1 or 2,
A film in which the layer A contains particles, and the volume of the particles is 0.5 or more. delete The method of claim 1 or 2,
Films with a 60° glossiness (G ₆₀ ) of less than 6. The method of claim 1 or 2,
A film with an MIT bending fracture count of 7500 or more in at least one of the longitudinal direction (MD) and transverse direction (TD). The method of claim 1 or 2,
A film whose thermal dimensional change rate in the longitudinal direction (MD) and transverse direction (TD) in the range of 100°C to 150°C is 0.015%/°C or less. The method of claim 1 or 2,
A film in which the center line average roughness (SRa) of the surface of layer A exceeds 1000 nm and is 3000 nm or less. The method of claim 1 or 2,
A film with a thermal contraction rate of 2% or less in both the longitudinal direction (MD) and the transverse direction (TD) at 150°C. The method of claim 1 or 2,
A film with a curl height of 0 mm or more and 30 mm or less after heat treatment at 150°C for 10 minutes, measured by the following method.
(Measurement method) The film is cut to a size of 100 mm in any one direction and 100 mm in a direction perpendicular to this direction to make a sample. After performing heat treatment by leaving the sample in a hot air circulation oven at 150°C for 10 minutes, it is placed on a glass plate, the amount of lifting at four corners in the vertical direction from the surface of the glass plate is measured, and the maximum height is taken as the curl height. The method of claim 1 or 2,
A film having a surface free energy of the A layer surface of 44 mN/m or less. The method of claim 1 or 2,
Film used for transfer purposes. A laminate comprising a release layer laminated on the surface of layer A of the film according to claim 1 or 2. delete delete