JP7424461B2 - film - Google Patents

Description

FIELD OF THE INVENTION The present invention relates to films.

In recent years, printed wiring boards have become more precise and denser due to the increased integration of circuits associated with the expansion of smartphones and tablets. During the manufacturing process of printed wiring boards, circuits are formed on the surface of an insulating base material (polyimide resin, polyphenylene sulfide resin, etc.), and then a cover layer, which is a heat-resistant resin film with an adhesive layer, is applied for the purpose of insulation and circuit protection. may be coated and molded by press lamination via a release film. At this time, the release film not only has releasability from the printed wiring board material and press plate, shape followability, and uniform moldability, but also transfers a matte appearance (low gloss appearance) to the object to be released. characteristics (matte appearance transferability) are required. Furthermore, there is an increasing need for a film that has a matte appearance transferability in transfer films that transfer functional layers such as insulating layers, hard coat layers, and electromagnetic shielding layers onto the surface of circuit boards by hot pressing.

Conventionally, processed products such as sand mat films, chemical mats, and coating mats have been commonly used as release films and transfer films with matte appearance transferability, but improvements have been made to address issues such as increased costs due to increased processes and quality issues. was desired. As a method for solving these problems, a particle-incorporated film has been proposed, which is manufactured by extruding a large amount of particles together with a resin. (For example, Patent Documents 1 and 2). Further, as a film having a highly matte appearance, a film whose surface is provided with a resin layer by coating has been proposed (for example, Patent Document 3).

JP2016-97522A JP2014-24341A JP2005-24942A

Although the films described in Patent Documents 1, 2, and 3 can lower the glossiness to some extent, it has been difficult to achieve the low-gloss appearance that is required in recent years regardless of the incident angle.
An object of the present invention is to solve the problems of the prior art described above. That is, the object is to provide a film that, when used as a transfer film, can transfer a uniform low-gloss appearance regardless of the angle of incidence.

In order to solve the above problems, the film of the present invention has the following configuration.
(1) A film having a low gloss layer (A layer) having a 60° glossiness (G ₆₀ ) and an 85° glossiness (G ₈₅ ) of 27 or less, wherein the A layer is a surface layer on at least one side. , the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) satisfy the following formula (I), a base material layer is provided on one side of the A layer, a base material layer, A film in which both the A layer has a polyester resin as a main component, and the thickness of the A layer is more than 3 μm and 20 μm or less.
0.1≦(G ₈₅ )/(G ₆₀ )≦3...(I)
(2) A film having a low gloss layer (A layer) having a 60° glossiness (G ₆₀ ) and an 85° glossiness (G ₈₅ ) of 27 or less, wherein the A layer is a surface layer on at least one side. , the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) satisfy the following formula (I), a base material layer is provided on one side of the A layer, a base material layer, A film whose main component is polyester resin for both layer A and whose heat shrinkage rate at 150°C in both the machine direction (MD) and the width direction (TD) is 2% or less.
0.1≦(G ₈₅ )/(G ₆₀ )≦3...(I)
(3) The film according to (1) or (2), wherein both the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) of the low gloss layer (A layer) are 10 or less.
(4) The film according to any one of (1) to (3), wherein the variation in tensile strength at break within a 20 cm x 30 cm range is 20% or less.
(5) The film according to any one of (1) to (4), wherein the layer A contains particles, and the circularity of the particles is 0.995 or less.
(6) The film according to (5), wherein the particles are inorganic particles.
(7) The film according to (5) or (6), wherein the particles have a bulk density of 0.5 or more.
(8) The film according to any one of (1) to (7), which is biaxially oriented.
(9) The film according to any one of (1) to (8), which has a 60° glossiness (G ₆₀ ) of less than 6.
(10) Any of (1) to (9) whose thermal dimensional change rate in the longitudinal direction (MD) and width direction (TD) in the range of 100°C to 150°C is 0.015%/°C or less. A film described in Crab.
(11) The film according to any one of (1) to (10), wherein the center line average roughness (SRa) of the surface of the A layer is more than 1000 nm and less than 3000 nm.
(12) The film according to any one of (1) to (11), which has a curl height of 0 mm or more and 30 mm or less after heat treatment at 150° C. for 10 minutes, as measured by the following method.
(Measurement method) The film is cut out to a size of 100 mm in one arbitrary direction and 100 mm in a direction orthogonal to that direction to use as a sample. After heat-treating the sample by leaving it in a hot air circulation oven at 150°C for 10 minutes, place it on a glass plate, measure the amount of lift of the four corners in the vertical direction from the glass plate surface, and determine the maximum height. Let be the curl height.
(13) The film according to any one of (1) to (12), wherein the surface of the layer A has a surface free energy of 44 mN/m or less.
(14) The film according to any one of (1) to (13), which is used for transfer purposes.
(15) A laminate comprising a release layer laminated on the surface of layer A of the film according to any one of (1) to (14).

The film of the present invention has low 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) of 27 or less, and the difference between them is controlled within a specific range, so it has excellent properties regardless of the incident angle. Since it exhibits a low-gloss appearance, when used as a transfer film, for example, it has excellent transferability that gives a low-gloss appearance to an object to be transferred. Therefore, for example, it can be suitably used as a transfer film with excellent matte appearance transferability in a circuit forming process. In addition, it is used to decorate molded parts such as building materials, electronic products such as automobile parts and smartphones, and home appliances, and to add functionality such as slipperiness, air release, and light diffusion to functional layers. It can also be suitably used in transfer applications.

FIG. 3 is a schematic diagram showing how to obtain bulkiness.

The film of the present invention is a film having a low gloss layer (A layer) having a 60° glossiness (G ₆₀ ) and an 85° glossiness (G ₈₅ ) of 27 or less, wherein the A layer is on at least one side. It is a film on the surface of The 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) are both preferably 10 or less, most preferably less than 6, from the viewpoint of low gloss appearance. The resin used for the low gloss layer is not particularly limited, but includes, for example, polyester such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyarylate, polyethylene, polypropylene, polyamide, polyimide, polymethylpentene, and polyvinyl chloride. , polystyrene, polymethyl methacrylate, polycarbonate, polyetheretherketone, polysulfone, polyethersulfone, fluororesin, polyetherimide, polyphenylene sulfide, polyurethane, and cyclic olefin resins. Among these, it is preferable to use polyester as the main component from the viewpoint of ease of handling the film, dimensional stability, and economic efficiency during production. In the present invention, the term "main component" means that the content is 50% by mass or more based on the entire layer.

In the present invention, polyester is a general term for polymers whose main bonds in the main chain are ester bonds, and can usually be obtained by polycondensation reaction of a dicarboxylic acid component and a glycol component.

The dicarboxylic acid components used here include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sodium sulfonedicarboxylic acid, etc. Aromatic dicarboxylic acids, oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid, aliphatic dicarboxylic acids such as fumaric acid, alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, paraoxybenzoic acid Various components such as oxycarboxylic acids and the like can be mentioned. In addition, as the dicarboxylic acid ester derivative component, esterified products of the above dicarboxylic acid compounds, such as dimethyl terephthalate, diethyl terephthalate, 2-hydroxyethylmethyl terephthalate, dimethyl 2,6-naphthalenedicarboxylate, dimethyl isophthalate, adipic acid Components such as dimethyl, diethyl maleate, and dimethyl dimerate may be mentioned. In the polyester resin constituting the resin film of the present invention, the proportion of terephthalic acid and/or naphthalene dicarboxylic acid in the total dicarboxylic acid component is preferably 85 mol% or more, more preferably 90 mol% or more. This is preferable from the viewpoint of performance and productivity.

In addition, as glycol components, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexane Diol, 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 include. Among these, 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 proportion of ethylene glycol in the total diol component is 65 mol% or more. Two or more of these dicarboxylic acid components and glycol components may be used in combination.

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

In the film of the present invention, when the film has a base layer on one side of the A layer, the resin constituting the base layer may be, for example, polyethylene terephthalate, similar to the resin used for the low gloss layer (A layer). Polyester such as polypropylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyarylate, polyethylene, polypropylene, polyamide, polyimide, polymethylpentene, polyvinyl chloride, polystyrene, polymethyl methacrylate, polycarbonate, polyether ether ketone, polysulfone, poly Ether sulfone, fluororesin, polyetherimide, polyphenylene sulfide, polyurethane, cyclic olefin resin, etc. can be used. Among these, it is preferable to use polyester as the main component from the viewpoint of ease of handling the film, dimensional stability, and economic efficiency during production.

In the film of the present invention, the thickness of the layer A is preferably more than 3 μm and less than 20 μm. By making the thickness of the A layer thicker than 3 μm, the number of particles in the A layer becomes sufficiently large, and it becomes easy to control both the 60° glossiness and the 85° glossiness to a low value of 20 or less. Further, even if the thickness of the A layer is made thicker than 20 μm, the influence on the gloss level is reduced, but the number of particles becomes too large, so that productivity may decrease. Therefore, the thickness of layer A is preferably 20 μm or less. The thickness of layer A is more preferably 3.5 μm or more and 15 μm or less, most preferably 4 μm or more and 10 μm or less.

In the film of the present invention, the low gloss layer (layer A) preferably contains particles. As the particles contained in layer A, both inorganic particles and organic particles can be used, and it is also possible to use inorganic particles and organic particles in combination. Here, the inorganic particles and/or organic particles used are not particularly limited, but for example, inorganic particles include silica, aluminum silicate, calcium carbonate, calcium phosphate, aluminum oxide, etc., and organic particles include: Particles containing styrene, silicone, acrylic acids, methacrylic acids, polyesters, divinyl compounds, etc. as constituent components can be used. Among these, it is preferable to use inorganic particles such as wet and dry silica, colloidal silica, and aluminum silicate, and particles containing styrene, silicone, acrylic acid, methacrylic acid, polyester, divinylbenzene, and the like as constituent components. From the viewpoint of low gloss appearance and economic efficiency, silica and aluminum silicate are particularly preferably used. Note that 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 red red, molybdenum red, cadmium red, red yellow lead, chrome permillion, ultramarine, navy blue, cobalt blue, and cerulean blue, chromium oxide, pyridian, emerald green, cobalt green, yellow lead, and cadmium. Inorganic pigments such as yellow, yellow iron oxide, titanium yellow, manganese violet, mineral violet, titanium dioxide, barium sulfate, zinc white, zinc sulfate, carbon black, black iron oxide, condensed azo, phthalocyanine, quinacridone, dioxazine, isoindolinone , quinophthalone, anthraquinone, and other organic pigments do not fall under the inorganic particles or organic particles of the present invention.

In the present invention, in order to lower both the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) of the surface of the low gloss layer (A layer), the average particle diameter It is preferable that particles having a diameter of 1.5 μm or more and 15 μm or less are contained in an amount of more than 18% by mass and not more than 40% by mass, with the entire A layer being 100% by mass. From the viewpoint of achieving a low-gloss surface, the average particle diameter of the particles in layer A is more preferably 3 μm or more and 15 μm or less, most preferably 6 μm or more and 15 μm or less. Further, the particle concentration in the A layer is more preferably 18% by mass or more and 40% by mass or less, and most preferably more than 22% by mass and 40% by mass or less, with the entire A layer being 100% by mass. The average particle diameter in the present invention refers to the number average diameter D expressed by D=ΣDi/N (Di: circle equivalent diameter of particle, N: number of particles).

In addition, in the present invention, in order to realize a low gloss surface independent of angle, the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) must satisfy the following formula (I). is necessary.
0.1≦(G ₈₅ )/(G ₆₀ )≦3...(I)
Satisfying formula (I) means that the difference between 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) is controlled to be small within a specific range, and is uniform regardless of the viewing angle. resulting in a low gloss surface. From the viewpoint of a uniform, low-gloss surface, it is more preferable that formula (II) is satisfied, and it is most preferable that formula (III) is satisfied.
0.1≦(G ₈₅ )/(G ₆₀ )≦2...(II)
0.1≦(G ₈₅ )/(G ₆₀ )≦1.5 (III).

In the present invention, a method in which the 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) of the low gloss layer (A layer) are both 27 or less and satisfies the above formula (I) is particularly Examples include, but are not limited to, a method using particles having a polyhedral shape, a method using monodisperse particles, a method using monodisperse particles having a polyhedral shape, and the like. By applying particles having a polyhedral shape or monodispersed particles, a non-uniform shape can be imparted to the film surface, making it easier to achieve low gloss in all directions. The polyhedral 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 preferably tetrahedral or more, and most preferably tetrahedron or more and octahedron or less. Further, the polyhedral shape in the present invention may be any shape as long as its surface is formed of various polygons such as triangles, quadrilaterals, and pentagons. In the film of the present invention, the particles contained in the low gloss layer (layer A) should have a projected image circularity (4π x area/perimeter ² ) of 0.995 or less as determined by the measurement method described below. is preferred. 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 grains will align in the stretching direction, making it difficult to form a shape with little direction dependence on the film surface. The circularity is preferably 0.800 or more. Further, in the film of the present invention, it is preferable that the particles contained in the low gloss layer (layer A) have a bulk degree of 0.5 or more as determined by the measuring method described below. When the film of the present invention is an oriented film, it is formed through a step of stretching the film. In this case, if the particles have a small bulk (acicular particles or plate-like particles), the direction of the particles will be aligned in the stretching direction, making it difficult to form a shape with little direction dependence on the film surface. By containing particles with a high bulk level in the low gloss layer (layer A), even if the film is formed through a stretching process, it is easy to give the film surface a shape with little direction dependence. Become. The bulk degree is more preferably 0.6 or more, still more preferably 0.7 or more. On the other hand, from the viewpoint of achieving low gloss without angle dependence by imparting a non-uniform shape to the film surface, the bulk degree is preferably 0.9 or less. Furthermore, in the present invention, monodisperse particles are particles that have almost no secondary agglomerated particles and are dispersed in the polymer as primary particles, and when the film is observed with a transmission electron microscope, the particle size is 0.01 mm. Refers to particles in which the number of ^secondary agglomerated particles per field of view is 20 or less.

In the present invention, in order to form a low-gloss surface that does not depend on the angle and to achieve both matte transferability and film strength, the A layer has a thickness of 4 μm or more and 10 μm or less, and the average particle diameter of the polyhedral shape is 6 μm or more. A very preferable embodiment is a structure in which particles of 15 μm or less are contained in an amount of 22% by mass or more and 40% by mass or less, with the entire A layer being 100% by mass.

From the viewpoint of improving film strength, the film of the present invention preferably has an MIT bending failure number of 7500 times or more in at least one direction among the longitudinal direction (MD) and the transverse direction (TD). By setting the number of MIT bending breaks to 7,500 times or more, it is possible to suppress the occurrence of tearing or cleavage when the film is peeled off after transfer. The number of MIT bending times is more preferably 7500 times or more in both the longitudinal direction (MD) and the width direction (TD). The method of making the MIT bending failure number in at least one of the longitudinal direction (MD) and the transverse direction (TD) 7,500 times or more is not particularly limited, but for example, when making a biaxially stretched polyester film, the A layer is A method in which stretching is carried out at a temperature equal to or higher than the crystallization temperature (Tcc) is preferably used. By applying these conditions, fine oriented crystals are formed before heat treatment and grow through heat treatment, thereby making it possible to reduce lamellae, which are considered to be the starting point of film breakage and cleavage.

The film of the present invention has a thermal dimensional change rate of 0.05 in both the longitudinal direction (MD) and the width direction (TD) in the range of 100°C to 150°C, from the viewpoint of improving quality in high-temperature processing such as heat pressing. The temperature is preferably 0.015%/°C or less. By setting the thermal dimensional change rate in the above direction to 0.015%/°C or less, it is possible to suppress the generation of wrinkles due to expansion deformation during high temperature processing. The thermal dimensional change rate is more preferably 0.012%/°C or less, most preferably 0.009%/°C or less. In the present invention, the method for achieving a thermal dimensional change rate of 0.015%/°C or less in the longitudinal direction (MD) and width direction (TD) in the range of 100°C to 150°C is not particularly limited, but for example, biaxial stretching When preparing a polyester film, a method is preferably used in which the temperature is lowered in stages after heat treatment and the film is relaxed at each stage.

In the film of the present invention, from the viewpoint of matte appearance transferability, it is preferable that the center line average roughness SRa of the surface of the A layer is more than 1000 nm and 3000 nm or less. If the center line average roughness SRa on the A layer side is 1000 nm or less, the matte tone transferability may not be sufficient, and if it is made larger than 3000 nm, the strength of the film may decrease. From the viewpoint of matte transferability and film strength, the center line average roughness SRa on the A layer side is more preferably 1100 nm or more and 2500 nm or less, most preferably 1200 nm or more and 2000 nm or less. In the present invention, methods for adjusting the center line average roughness SRa on the A layer side to be more than 1000 nm and less than 3000 nm include, but are not limited to, a method of adjusting the content of particles in the A layer, a method of adjusting the content of particles in the A layer, A preferred method is to reduce voids around the particles contained therein. By reducing the voids around the particles, it becomes easier to form the shape of the particles on the surface, and it becomes easier to control the center line average roughness SRa to more than 1000 nm and 3000 nm or less. As a method for reducing voids around particles in layer A, for example, when both the base layer and the low gloss layer (layer A) are made of polyester and a biaxially stretched polyester film is made, the low gloss layer (layer A) is Preferably used is a method of increasing stretchability, a method of reducing voids by performing treatment at a high temperature in the post-stretching heat treatment step described below, and the like. The low gloss layer (layer A) may contain a copolymerized polyethylene terephthalate resin, a polypropylene terephthalate resin and/or a copolymer thereof, a polybutylene terephthalate resin and/or a copolymer thereof, in order to improve stretchability. preferable.

The film of the present invention preferably has a heat shrinkage rate of 2% or less at 150° C. in both the longitudinal direction (MD) and the transverse direction (TD) from the viewpoint of dimensional stability of the film. By controlling the heat shrinkage rate at 150° C. in the longitudinal direction (MD) and the width direction (TD) to a low value of 2% or less, it is possible to suppress the occurrence of curls, wrinkles, etc. in various processing steps. In order to further improve dimensional stability, the present invention preferably has a heat shrinkage rate of 1.8% or less in the longitudinal direction (MD) and width direction (TD) at 150°C, and even if it is 1.5% or less. most preferred.

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 is defined as the curl height after a 10-minute heat treatment at 150°C. After being heat-treated by leaving it in a circulation oven for 10 minutes, it is placed on a glass plate, and the amount of lift of the four corners in the vertical direction from the glass plate surface is measured, and the maximum height is calculated as the curl height. The curl height is more preferably 0 mm or more and 25 mm or less, and most preferably 0 mm or more and 20 mm or less.

In the present invention, a method in which the heat shrinkage rate in the longitudinal direction (MD) and the width direction (TD) at 150°C is 2% or less, and a method in which the curl height after heat treatment at 150°C for 10 minutes is 0 mm or more and 30 mm or less The method is not particularly limited, but includes, for example, 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 the heat shrinkage rate tends to be reduced, but from the viewpoint of dimensional stability and film quality, the heat treatment temperature after biaxial stretching is 220 ° C to 240 ° C. Preferably, the temperature is between 225°C and 240°C, more preferably between 230°C and 240°C, and most preferably between 230°C and 240°C. The heat treatment temperature of the film can be determined from the minute endothermic peak caused by the thermal history in the DSC curve when measured using a differential scanning calorimeter (DSC) at a heating rate of 20°C/min in a nitrogen atmosphere. In the film of the present invention, the slight endothermic peak temperature is preferably 220 to 240°C.

Further, the preferable heat treatment time can be arbitrarily set to 5 to 60 seconds, but from the viewpoint of dimensional stability, film quality, and productivity, it is preferably 10 to 40 seconds, and 15 to 30 seconds. It is preferable that Further, the heat shrinkage rate can be reduced by performing the heat treatment while relaxing the film in the longitudinal direction and/or the width direction. The relaxation rate during relaxation during heat treatment is preferably 1% or more, and from the viewpoint of dimensional stability and productivity, it is preferably 1% or more and 10% or less, and 1% or more and 5% or less. most preferred.

Further, a method of heat treatment using two or more stages of conditions is also very preferable. After heat treatment at a high temperature of 220 ° C. to 240 ° C., heat treatment is performed at a temperature lower than the heat treatment temperature while relaxing in the longitudinal direction and/or width direction, thereby making it possible to further reduce the heat shrinkage rate. The second stage heat treatment temperature at this time is preferably from 120°C to less than 200°C, more preferably from 150°C to 180°C. In addition, as a method for setting the curl height after heat treatment at 150°C for 10 minutes to 0 mm or more and 30 mm or less, it is possible to A method of providing a cooling nip roll on the opposite side of the surface is also preferably used. In addition, when the film of the present invention has a film structure having the above-mentioned layer A on at least one side of the base layer, the layer A may be formed on both sides of the base layer, and the layer A may be formed on one side of the base layer. Even in the case where the resins have a similar composition, it is preferable that the resins of the base layer and the A layer have similar compositions.

The film of the present invention preferably has a variation in tensile strength at break of 20% or less in a 20 cm x 30 cm range. By reducing the variation in tensile strength at break, the handling properties of the film are improved, and it is possible to suppress the occurrence of film tearing at locations where the strength is weak during film transport and transfer peeling. The variation in tensile strength at break in a 20 cm x 30 cm range of the film in the present invention can be determined by cutting a sample of the film at an arbitrary position into a size of 20 cm wide x 30 cm long, and dividing it into two equal 15 cm pieces in the length direction. A 15 cm long sample is cut into 1 cm wide pieces in the width direction, and the breaking strength of 40 strip-shaped samples each having a length of 15 cm and a width of 1 cm is measured and calculated by a tensile test. The variation in tensile strength at break in the 20 cm x 30 cm range of the film is more preferably 15% or less, and most preferably 0.1% or more and 10% or less.

An example of a method for 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 is a method of improving the dispersibility of particles contained in layer A. The dispersibility of the particles is improved and the particles are uniformly present in the A layer, so that variations in tensile strength at break can also be reduced. The method for improving the dispersibility of the particles is not particularly limited, but for example, compounding the particles with a resin that is highly compatible with the base resin constituting the A layer, extruding the particle compound raw material into the base resin as an alloy, Examples include a method of forming layer A. For example, when the base resin is polyethylene terephthalate, it is preferable to select polybutylene terephthalate, polypropylene terephthalate, etc. as the compounding resin.

In the film of the present invention, the surface free energy of the A layer surface is preferably 44 mN/m or less from the viewpoint of transferability. By setting the surface free energy to 44 mN/m or less, the releasability from the transfer material is improved, so that transfer and peeling become easy, and the transferability is improved. The surface free energy on the A layer side is more preferably 40 mN/m or less, most preferably 35 mN/m or less. On the other hand, from the viewpoint of uniform application of the transfer material and adhesion during processing, it is preferably 20 mN/m or more.

Examples of the method of controlling the surface free energy of the present invention within the above-mentioned range include, but are not particularly limited to, 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, layer A is a layer containing a melamine resin and a mold release agent (hereinafter, a layer containing a mold release agent may be referred to as a mold release layer). is preferred. From the viewpoint of heat resistance and mold release stability, the content of the melamine resin in layer A is preferably 50% by mass or more.

Examples of melamine resins include melamine formaldehyde resins such as melamine formaldehyde resins, methylated melamine formaldehyde resins, butylated melamine formaldehyde resins, etherified melamine formaldehyde resins, and epoxy-modified melamine formaldehyde resins, urea melamine resins, and acrylic melamine resins. , melamine formaldehyde resins are preferred, and methylated melamine formaldehyde resins are particularly preferably used because they have appropriate mold release properties. Further, from the viewpoint of film formability and stretch followability, the A layer of the present invention preferably contains a binder resin in addition to the binder resin and the mold release agent. As the binder resin, polyester resins, acrylic resins, and urethane resins are preferably used, and acrylic resins are particularly preferably used. Examples of the acrylic resin include homopolymers or copolymers of (meth)acrylic acid alkyl esters, and (meth)acrylic ester copolymers having a curable functional group at the end of the side chain and/or main chain. Examples of the curable functional group include hydroxyl group, carboxyl group, epoxy group, and amino group. Among these, an acrylic monomer copolymer in which an acrylic monomer and an acrylic ester having a curable functional group at the end of the side chain and/or main chain is copolymerized is preferred. Furthermore, examples of the mold 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 alone or in combination.

The fluorine compound that can be used in the present invention is a compound containing a fluorine atom in the compound. 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 simultaneous molding transfer foil applications, etc., a high heat load is applied during transfer, so in consideration of heat resistance and stain resistance, the fluorine compound is preferably a polymer compound.

A long-chain alkyl compound is a compound having a linear 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, and long-chain alkyl groups. Containing ether compounds, long-chain alkyl group-containing quaternary ammonium salts, and the like. It is preferable that the long-chain alkyl compound is a polymeric compound, since it is possible to suppress the components derived from layer A from being transferred to the surface of the mating substrate when the release film is peeled off.

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

By uniformly dispersing these mold release agents on the surface of layer A, the adhesion and peeling force with the release layer laminated on layer A and peeled off can be controlled within appropriate ranges. It is preferable to use a long-chain alkyl compound as the mold release agent in view of the use of the present invention since the release force can be adjusted over a wide range.

Next, specific examples of the method for producing the film of the present invention will be described, but the present invention is not to be interpreted as being limited to such examples.

When the film of the present invention is composed of a base layer and a low gloss layer (layer A), and polyester resin is used for each layer, each resin is supplied to separate extruders and melt-extruded. At this time, the resin temperature is preferably controlled to 255°C to 295°C. Next, foreign matter is removed and the extrusion amount is equalized through a filter or a gear pump, and the product is coextruded into a sheet from a T-die onto a cooling drum to obtain a laminated sheet. At that time, the electrostatic application method uses electrodes to which high voltage is applied to bring the cooling drum and resin into close contact with static electricity, the casting method creates a water film between the casting drum and the extruded polymer sheet, and the casting drum temperature is controlled to increase the temperature of the polyester resin. A sheet-like polymer is brought into close contact with a casting drum by a method of adhering the extruded polymer at a temperature between the glass transition point and (glass transition point -20° C.), or by a method combining multiple of these methods, and then cooled and solidified. Among these casting methods, when using polyester, the method of electrostatic application is preferable from the viewpoint of productivity and flatness, and from the viewpoint of suppressing curling during heating, a cooling nip roll is placed on the side opposite to the cooling drum. Also preferably used is a method of providing. The film of the present invention is preferably a biaxially oriented film from the viewpoint of heat resistance and dimensional stability. Biaxially oriented films can be 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 by a sequential biaxial stretching method in which an unstretched film is stretched in the longitudinal direction and then stretched in the longitudinal direction. , can be obtained by stretching by a simultaneous biaxial stretching method in which the width direction is stretched almost simultaneously.

The stretching ratio in this stretching method is preferably 2.8 times or more and 3.4 times or less, more preferably 2.9 times or more and 3.3 times or less in the longitudinal direction. Further, the stretching speed is desirably 1,000%/min or more and 200,000%/min or less. Further, the stretching temperature in the longitudinal direction is preferably 70°C or more and 90°C or less. Further, the stretching ratio in the width direction is preferably 2.8 times or more and 3.8 times or less, 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. Further, 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 preferably a temperature higher than the crystallization temperature of the A layer. Furthermore, the film is heat treated after biaxial stretching. The heat treatment can be performed by any conventionally known method such as in an oven or on a heated roll. This heat treatment is carried out at a temperature of 120°C or higher and lower than the crystal melting peak temperature of polyester, but from the perspective of reducing voids around the particles in layer A, the heat shrinkage rate at 150°C is controlled to be as low as 2% or less. Also from the viewpoint of this, the heat treatment temperature is preferably as high as 220° C. or higher. Further, from the viewpoint of keeping the thermal dimensional change rate in the range of 100° C. to 150° C. to 0.015%/° C. or less, it is preferable to perform a relaxation treatment while lowering the temperature in stages after the heat treatment. More specifically, a relaxation heat treatment with a relaxation rate of 0.5% or more is performed at the maximum temperature (Tmax) of heat treatment, and then a relaxation rate of 0.5% or more is performed at a temperature of Tmax - 50°C or more and Tmax - 5°C or less. It is preferable to perform one or more stages of relaxation heat treatment. The 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 higher, and Tmax-50°C or higher and lower than Tmax-25. . Relaxation heat treatment may be performed in either the longitudinal direction or the width direction, but when biaxial stretching is performed by sequential biaxial stretching, relaxation heat treatment is performed continuously after stretching in the second stretching direction. This is preferable from the viewpoint of productivity.

Furthermore, in order to ensure stable mold releasability, the film of the present invention is also preferably formed into a laminate in which a mold release layer is provided on the surface of layer A of the film. The method of providing the release layer is not particularly limited, but an in-line coating method can be mentioned. A method for providing a coating layer in-line during the film manufacturing process is to uniformly apply a coating layer composition dispersed in water onto a film that has been uniaxially stretched using a metal ring bar, gravure roll, etc. However, a method of drying the coating material while stretching is preferred, and in this case, the thickness of the release layer 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. good.

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

(1) Composition of polyester It is possible to dissolve the polyester resin and film in hexafluoroisopropanol (HFIP) and quantify the content of each monomer residue component and by-product diethylene glycol using ¹ H-NMR and ¹³ C-NMR. can. In the case of a laminated film, by scraping each layer of the film according to the laminated thickness, the components constituting each layer can be collected and evaluated. In addition, regarding the film of the present invention, the composition was calculated 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 by dissolving the polyester in orthochlorophenol and using an Ostwald viscometer at 25°C. In the case of a laminated film, the intrinsic viscosity of each layer can be evaluated by scraping each layer of the film according to the laminated thickness.

(3) Film thickness The film thickness was measured using a dial gauge.

(4) Thickness of each layer The film was embedded in epoxy resin, and a cross section of the film was cut out using a microtome. The cross section was observed with a transmission electron microscope (TEM H7100 manufactured by Hitachi) at a magnification of 5000 times,
The thickness of each layer was determined.

(5) Average particle size of the particles The resin is removed from the film using a plasma low-temperature ashing method (Model PR-503 manufactured by Yamato Scientific Co., Ltd.) to expose the particles. This was observed with a transmission electron microscope (TEM H7100 manufactured by Hitachi), and the image of the particles (shade of light created by the particles) was connected to an image analyzer (QTM900 manufactured by Cambridge Instruments), and the number of particles was determined by changing the observation point to 100. The following numerical processing was performed, and the number average diameter D obtained thereby was taken as 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) Particle images were observed in the same manner as for particle shape/circularity (5). Further, the circularity was calculated using the following formula, and the average value of 100 particles was defined as the circularity of the present invention.
Circularity = 4π x area / perimeter ²
(7) Particle shape/bulkness A cross section of the film 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 are cut out with a microtome and described in (5). Observations were made using the following method. The length at which the ends of the particle are the longest in the cross section is L1, and when calculating L1, the length at which the ends of the particle are the longest in the perpendicular direction of the line segment connecting the ends of the particle. Let it be L2 (Figure 1). The bulkiness is determined by calculating L2/L1 in each of the film cross section parallel to the film longitudinal direction and perpendicular to the film thickness direction, and the film cross section parallel to the film width direction and perpendicular to the film thickness direction, and determining it as the average of 100 pieces. Ta.

(8) Content of particles 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 after dissolution, and the liquid was then centrifuged to sediment the particles, and the supernatant liquid was removed. The particles were further washed with water and centrifuged twice. The particles thus obtained were dried and their mass was measured to calculate the content of the particles.

(9) Glossiness In accordance with the method specified in JIS-Z-8741 (1997), 60° specular gloss and 85° specular gloss were measured using a digital variable angle gloss meter UGV-5D manufactured by Suga Test Instruments. Each was measured at N=3, and the average values were taken as the 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) of the present invention.
(10) MIT bending frequency The polyester film was cut into a rectangular shape with a width of 15 mm and a length of 100 mm to prepare a sample. Using an MIT folding durability tester (manufactured by Mize Test Instruments Co., Ltd.), the film was measured three times each in the longitudinal direction and the width direction, and then the average value was calculated.

・Tip: R0.38mm
・Bending angle: 135° left and right
・Bending speed: 175 reciprocations/min ・Load: 9.8N
(11) Center line average roughness SRa
A sample was cut into a size of 4.0 cm long x 3.5 cm wide, and was measured using a stylus method high-definition micro-shape measuring device (3-dimensional surface roughness meter) in accordance with JIS B0601-1994. The surface morphology of the film was measured under the following conditions.
・Measuring device: 3D micro-shape measuring device (manufactured by Kosaka Laboratory Co., Ltd., ET-4000A type)
・Analysis equipment: 3D surface roughness analysis system (TDA-31 type)
・Stylus: Tip radius 0.5μmR, diameter 2μm, made of diamond ・Stylus pressure: 100μN
・Measurement direction: Average after measuring once each in the film longitudinal direction and film width direction ・X measurement length: 1.0 mm
・X feed speed: 0.1mm/s (measurement speed)
・Y feed pitch: 5μm (measurement interval)
・Number of Y lines: 81 (number of measurements)
・Z magnification: 20x (vertical magnification)
・Low cutoff: 0.20mm
- High frequency cutoff: R+Wmm (roughness cutoff value) R+W means no cutoff.
・Filter method: Gaussian spatial type ・Leveling: Yes (tilt correction)
・Reference area: 1mm ² .
Measurement was performed under the above conditions, and then the centerline average roughness SRa was calculated using an analysis system.

(12) Thermal dimensional change rate in the range of 100°C to 150°C Cut a sample into a rectangle of 50 mm long x 4 mm wide so that the longitudinal direction (MD) and transverse direction (TD) are the length directions, and heat Using a mechanical analyzer (TMA EXSTAR 6000, manufactured by Seiko Instruments), the temperature was raised under the following conditions, and the thermal dimensional change rate 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 five samples of each film in the longitudinal direction and the width direction, and the average value was evaluated.

(13) Heat shrinkage rate at 150° C. A sample was cut out into a rectangular shape with a length of 150 mm and a width of 10 mm so that the longitudinal direction (MD) and the width direction (TD) were the respective length directions. Marked lines were drawn on the sample at 100 mm intervals, and a 3 g weight was suspended and the sample was placed in a hot air oven heated to 150° C. for 30 minutes to perform heat treatment. The distance between the gauge lines after the heat treatment was measured, and the heat shrinkage rate was calculated from the change in the distance between the gauge lines before and after heating using the following formula. Five samples of each film were measured in the longitudinal direction and the width direction, and the average value was used for evaluation.
Heat shrinkage rate (%) = {(distance between gauge lines before heat treatment) - (distance between gauge lines after heat treatment)}/(distance between gauge lines before heat treatment) x 100.

(14) Cut out the curl height film after heat treatment at 150° C. for 10 minutes into a size of 100 mm in one arbitrary direction and 100 mm in a direction perpendicular to that direction to use as a sample. After heat-treating the sample by leaving it in a hot air circulation oven at 150°C for 10 minutes, place it on a glass plate, measure the lift of the four corners in the vertical direction from the glass plate surface, and calculate the maximum height. Curl height.

(15) Variation in tensile breaking strength in a 20 cm x 30 cm range of film A sample of the film was cut out into a size of 20 cm wide x 30 cm long at an arbitrary position, and the sample was divided into two equal parts of 15 cm in the length direction, each of which was 15 cm long. The sample was cut out to a width of 1 cm in the width direction to create 40 strip-shaped samples with a length of 15 cm and a width of 1 cm. The sample was subjected to a tensile test using a tensile tester (Tensilon UCT-100 manufactured by Orientec Co., Ltd.) with an initial distance between the tension chucks of 50 mm and a tensile speed of 300 mm/min. Strength) was measured, and the variation was determined as shown below.
Variation in tensile breaking strength (%) = {(maximum value - minimum value)/average value} x 100
(16) Surface free energy Four types of measurement liquids were used: water, ethylene glycol, formamide, and diiodomethane. The static contact angle was determined. 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 equation below to form a simultaneous equation consisting of four equations: γ ^L , γ ⁺ , We solved for γ ^- .
(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 ⁺ , γ ⁻ are the surface free energy of the film surface, long-range force term, Lewis acid parameter, Lewis base parameter, respectively, and γj, γj ^L , γj ⁺ , γj ⁻ show the surface free energy, long-range force term, Lewis acid parameter, and Lewis base parameter of the measurement liquid used, respectively. Moreover, the surface tension of each liquid used here was the value proposed by Oss ("Fundamentals of Adhesion", LH Lee (Ed.), p153, Plenum ess, New York (1991).).

(17) A releasable film was cut out to a length of 100 mm and a width of 100 mm. The following coating composition for forming a hard coat layer was applied using a slot die coater while controlling the flow rate so that the thickness after drying was 5 μm, dried at 100°C for 1 minute to remove the solvent, and then coated with a hard coat layer. A laminate in which coat layers were laminated was obtained.
The obtained film/hard coat layer laminate was heated to 160°C for both the upper mold temperature and the lower mold temperature, using a press machine to form a 0.2 mm thick aluminum plate/0.125 mm thick polyimide film. (Kapton 500H/V manufactured by DuPont Toray) / Laminated body / Polyimide film with a thickness of 0.125 mm (Kapton 500H/V manufactured by DuPont Toray) / Structure of an aluminum plate with a thickness of 0.2 mm under conditions of 1.5 MPa. Heat pressing was performed for 1 hour. After hot pressing, the laminate is taken out and irradiated with ultraviolet rays of 300 mJ/cm ² from the laminate side using a high-pressure mercury lamp to harden the hard coat layer and obtain a sample. A peel test was performed on this sample at the interface between the film and the hard coat layer, and the peelability was evaluated based on the following criteria. In addition, when the film was provided with a release layer, a peel test was conducted at the interface between the film/release layer and the hard coat layer. The peel test was performed five times and evaluated based on the following evaluation criteria.

(Coating composition for forming hard coat layer)
The following materials were mixed and diluted with methyl ethyl ketone to obtain a coating composition for forming a hard coat layer having a solid content concentration of 40% by mass.
Toluene 30 parts by mass Polyfunctional urethane acrylate 25 parts by mass (KRM8655 manufactured by Daicel Allnex Corporation)
Pentaerythritol triacrylate mixture 25 parts by mass (PET30 manufactured by Nippon Kayaku Co., Ltd.)
1 part by mass of polyfunctional silicone acrylate (EBECRYL1360 manufactured by Daicel Allnex Corporation)
Photopolymerization initiator 3 parts by mass (Irgacure 184 manufactured by Ciba Specialty Chemicals)
(Evaluation criteria)
A: The film could be peeled off without resistance, and no film breakage occurred (in all 5 peel tests).

B: Although resistance was felt during peeling, peeling was possible, and no film breakage occurred (in all 5 peeling tests).

C: Peeling was possible, but film tearing occurred during peeling (in any of the 5 peeling tests).

D: Peeling was not possible (in all 5 peeling tests).

(18) Curl property after heat pressing After heat pressing the laminate in the same manner as in (17), place it on a glass plate and measure the amount of lift of the four corners in the vertical direction from the glass plate surface. The height was defined as the curl height.

A: Curl height is 0 mm or more and less than 10 mm B: Curl height is 10 mm or more and less than 20 mm C: Curl height is 20 mm or more and less than 30 mm D: Curl height is 30 mm or more.

(18) Transferability of Matte Appearance, Uniform Appearance Glossiness was measured on the peeled surface side of the hard coat layer obtained by the method of (17), and the average value was evaluated according to the following criteria.
(Transferability with matte appearance)
A: Both 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) are 10 or less. B: One of 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) is 10 or less. However, the other one was greater than 10 and less than 27. C: Both 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) were 10 or more and 27 or less. D: 60° glossiness At least one of the glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) was greater than 27.

(Matte-like appearance, 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>( _G85 )/( _G60 ) or ( _G85 )/( _G60 )>3
(19) Transfer Quality The appearance of the peeled surface side of the hard coat layer obtained by the method (17) was visually observed and evaluated based on the following criteria.
A: No wrinkles visible B: Does not fall under A, with 2 or less wrinkles C: Does not fall under A or B, has 5 or less wrinkles D: Does not fall under A, B, or C Not applicable.

(Production of polyester)
The polyester resin used for film formation was prepared as follows.

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

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

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

(Polyester D)
“Hytrel (registered trademark)” 7247 manufactured by DuPont Toray.

(Particle Master E)
Polyethylene terephthalate particle master (intrinsic viscosity 0.7) containing aluminum silicate particles with an average particle diameter of 6 μm and a hexahedral shape in polyester A at a particle concentration of 30% by mass.

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

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

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

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

(Particle Master K)
Polyethylene terephthalate particle master (intrinsic viscosity 0.7) containing aluminum silicate particles with an average particle diameter of 6 μm and a hexahedral shape in polyester C at a particle concentration of 30% by mass.

(Particle Master L)
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 C at a particle concentration of 30% by mass.

(Particle Master M)
Polyethylene terephthalate particle master (intrinsic viscosity 0.7) containing aluminum silicate particles with an average particle diameter of 10 μm and a hexahedral shape in polyester C at a particle concentration of 30% by mass.

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

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

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

(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.

(Release layer forming solution (aqueous dispersion))
The following crosslinking agent: binder resin: mold release agent: particles were mixed at a mass ratio of 60:23:17, and diluted with pure water to adjust the solid content to a mass ratio of 1%.
・Crosslinking agent: Methylated melamine/urea copolymer crosslinked resin (“Nicalac” (registered trademark) “MW12LF” manufactured by Sanwa Chemical Co., Ltd.)
・Binder resin I: Acrylic monomer copolymer (manufactured by Nippon Carbide)
- Mold release agent: In a glass reaction vessel, CF ₃ (CF ₂ ) _n CH ₂ CH ₂ OCOCH=CH ₂ (n=5 to 11, average of n=9) 80. 0 g, acetoacetoxyethyl methacrylate 20.0 g, dodecyl mercaptan 0.8 g, deoxygenated pure water 354.7 g, acetone 40.0 g, C ₁₆ H ₃₃ N(CH ₃ ) ₃ Cl 1.0 g and C ₈ H ₁₇ C ₆ Add 3.0 g of H ₄ O (CH ₂ CH ₂ O) _n H (n=8), add 0.5 g of azobisisobutyramidine dihydrochloride, and copolymerize at 60°C for 10 hours with stirring under nitrogen atmosphere. Copolymer emulsion obtained by reaction.
・Particles: Water obtained by diluting silica particles (“Snowtex” (registered trademark) MP2040 manufactured by Nissan Chemical Industries, Ltd.) with an average particle diameter of 170 nm with pure water so that the solid content concentration is 40% by mass. Dispersion.

(Example 1)
Each raw material was supplied to the extruder so that the composition and lamination ratio were as shown in the table, the extruder cylinder temperature was set at 270°C, the short tube temperature was set at 275°C, the mouth temperature was set at 280°C, and the resin temperature was set at 280°C. Then, the mixture was discharged into a sheet from a T-die onto a cooling drum whose temperature was controlled at 25°C. At that time, an unstretched sheet was obtained by applying electrostatic charge using a wire-shaped electrode with a diameter of 0.1 mm and bringing it into close contact with the cooling drum, and further installing a cooling nip roll whose temperature was controlled at 25°C on the opposite side of the cooling drum. Ta. Next, it was stretched 3.1 times in the longitudinal direction at a stretching temperature of 85°C, and then subjected to corona discharge treatment, and the release layer forming solution (aqueous dispersion) was stretched to a wet thickness of 13.5 μm using a metering bar. It was then stretched in the width direction at a stretching temperature of 100° C. and a stretching ratio of 3.3 times using a tenter type transverse stretching machine. Thereafter, heat treatment was performed at 235°C for 15 seconds in a tenter, followed by heat treatment at 175°C for 10 seconds while relaxing 3.5% in the width direction to obtain a film with a thickness of 50 μm (low gloss layer (Layer A) The surface was the A1 side, and the surface on the base layer side was the B side.

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

(Example 9)
A film having a 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)
With the composition as shown in the table, when extruding a sheet from an extruder onto a cooling drum, an unstretched sheet was obtained without providing a cooling nip roll on the side opposite to the cooling drum, and after stretching in the manual direction, corona discharge treatment and separation were performed. A film having a thickness of 50 μm was obtained in the same manner as in Example 4, except that the mold layer coating was not performed.

(Example 11)
A film having a thickness of 50 μm was obtained in the same manner as in Example 5, except that the composition was as shown in the table and the three-layer structure was layer A/base layer/layer A.

(Example 12)
A film having a thickness of 50 μm was obtained in the same manner as in Example 5, except that the composition was as shown in the table and the three-layer structure was layer A/base layer/layer A.

(Example 13)
A film having a thickness of 38 μm was obtained in the same manner as in Example 5, except that the composition was as shown in the table and the three-layer structure of layer A/base layer/layer A was used.

(Example 14)
A film having a 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 having a 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 having a thickness of 50 μm was obtained in the same manner as in Example 5, except that after stretching in the longitudinal direction, no corona discharge treatment and no release layer coating were performed.

(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 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 140° C.

(Example 19)
A film having a 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 having a 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, except that after stretching in the width direction, relaxation heat treatment was performed in the width direction at 235°C for 2.0% and at 210°C for 1.5% for 5 seconds each. A film having a thickness of 50 μm was obtained in the same manner as in Example 1.

(Example 22)
The composition was changed as shown in the table, and after stretching in the width direction, relaxation heat treatment was performed in the width direction at 1.5% at 235°C, 1.0% at 215°C, and 1.0% at 200°C. A film with a thickness of 50 μm was obtained in the same manner as in Example 1, except that each test was carried out for 5 seconds.

(Example 23)
A film with a film thickness of 50 μm was prepared in the same manner as in Example 1, except that the composition was changed as shown in the table and a relaxation heat treatment in the width direction was performed at 240 ° C. for 3.5% for 15 seconds after stretching in the width direction. Obtained.

(Example 24)
The composition was changed as shown in the table, except that after stretching in the width direction, relaxation heat treatment was performed in the width direction at 235°C for 2.0% and at 210°C for 1.5% for 5 seconds each. A film having a thickness of 50 μm was obtained in the same manner as in Example 1.

(Example 25)
The composition was changed as shown in the table, and after stretching in the width direction, relaxation heat treatment was performed in the width direction at 1.5% at 235°C, 1.0% at 215°C, and 1.0% at 200°C. A film with a thickness of 50 μm was obtained in the same manner as in Example 1 except that each test was carried out for 5 seconds.

(Comparative example 1)
A film having a 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 having a 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 having a 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 having a 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 having a 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)
A film having a thickness of 50 μm was obtained in the same manner as in Example 1 except that the composition was as shown in the table and the stretching ratio in the width direction was 3.8 times.

(Comparative example 7)
A film having a 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 low 60° glossiness (G ₆₀ ) and 85° glossiness (G ₈₅ ) of 27 or less, and the difference between them is controlled to be small within a specific range, so it is excellent regardless of the incident angle. It exhibits a low-gloss appearance, and when used as a transfer film, has excellent transferability with a low-gloss appearance. Therefore, for example, it can be suitably used as a transfer film with excellent matte appearance transferability in a circuit forming process. In addition, it is used to decorate molded parts such as building materials, electronic products such as automobile parts and smartphones, and home appliances, and to add functionality such as slipperiness, air release, and light diffusion to functional layers. It can also be suitably used in transfer applications.

Claims (14)

A film having a low gloss layer (A layer) having a 60° glossiness (G ₆₀ ) and an 85° glossiness (G ₈₅ ) of 27 or less, the A layer being on at least one surface layer, The 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) satisfy the following formula (I), the A layer has a base layer on one side, and both the base layer and the A layer A film containing polyester resin as a main component and having a thickness of the layer A exceeding 3 μm and not more than 20 μm.
0.1≦(G ₈₅ )/(G ₆₀ )≦3...(I) A film having a low gloss layer (A layer) having a 60° glossiness (G ₆₀ ) and an 85° glossiness (G ₈₅ ) of 27 or less, the A layer being on at least one surface layer, The 60° glossiness (G ₆₀ ) and the 85° glossiness (G ₈₅ ) satisfy the following formula (I), the A layer has a base layer on one side, and both the base layer and the A layer A film whose main component is polyester resin and whose heat shrinkage rate at 150°C in both the machine direction (MD) and the width direction (TD) is 2% or less.
0.1≦(G ₈₅ )/(G ₆₀ )≦3...(I) The film according to claim 1 or 2, wherein the low gloss layer (A layer) has a 60° glossiness (G ₆₀ ) and an 85° glossiness (G ₈₅ ) of 10 or less. The film according to any one of claims 1 to 3 , wherein the A layer contains particles, and the circularity of the particles is 0.995 or less. The film according to claim 4 , wherein the particles are inorganic particles. The film according to claim 4 or 5 , wherein the particles have a bulk density of 0.5 or more. The film according to any one of claims 1 to 6 , which is biaxially oriented. The film according to any one of claims 1 to 7 , having a 60° glossiness (G ₆₀ ) of less than 6. The film according to any one of claims 1 to 8 , which has a thermal dimensional change rate of 0.015%/°C or less in both the longitudinal direction (MD) and the width direction (TD) in the range of 100°C to 150°C. . The film according to any one of claims 1 to 9 , wherein the center line average roughness (SRa) of the surface of the A layer is more than 1000 nm and less than 3000 nm. The film according to any one of claims 1 to 10, which has a curl height of 0 mm or more and 30 mm or less after heat treatment at 150° C. for 10 minutes, as measured by the following method.
(Measurement method) The film is cut out to a size of 100 mm in one arbitrary direction and 100 mm in a direction orthogonal to that direction to use as a sample. After heat-treating the sample by leaving it in a hot air circulation oven at 150°C for 10 minutes, place it on a glass plate, measure the amount of lift of the four corners in the vertical direction from the glass plate surface, and determine the maximum height. Let be the curl height. The film according to any one of claims 1 to 11 , wherein the surface free energy of the A layer surface is 44 mN/m or less. The film according to any one of claims 1 to 12 , which is used for transfer purposes. A laminate comprising a release layer laminated on the surface of layer A of the film according to any one of claims 1 to 13 .

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