TWI761493B - film - Google Patents

Abstract

The present invention provides a thin film having a surface roughness SRa of at least one side of 100 nm or more and 3000 nm or less, the variation of the surface roughness SRa in the range of 20 cm×14 cm is 10% or less, and the parallel line transmittance ST320 of 320 nm is When the film with more than 30% is used as the transfer film, the low-gloss appearance can be uniformly transferred, and when the photocurable resin is used as the transfer material, the transfer of the low-gloss appearance and the shape fixation can also be achieved, and it has Good processing step suitability that is less prone to problems such as particle shedding or chipping.

Description

film

The present invention relates to a film.

In recent years, due to the integration of circuits due to the expansion of smartphones and tablet computers, printed wiring boards have been gradually developed with high precision and high density. In the production step of the printed wiring board, after providing a circuit on the surface of an insulating base material (polyimide resin, polyphenylene sulfide resin, etc.), it is coated with a heat-resistant resin film having an adhesive layer for the purpose of insulating and protecting the circuit The coverlay is formed by press lamination through a release film. In this case, the mold release film is required to have releasability with a printed wiring board material or a pressure plate, shape conformability, uniform moldability, transferability with a matte appearance, and the like. In addition, the demand for matte-finishing films for substrates formed by thermally pressing functional layers such as insulating layers, hard coat layers, and electromagnetic wave shielding layers onto the surface of circuit substrates is increasing.

As far as matte films are concerned, they are generally processed products such as sand matte films, chemical matte films or coated matte films. However, the processed product has problems in terms of cost increase and quality due to an increase in the number of steps, and improvement is desired. In view of these problems, although the film with smelted particles produced by the method of extruding a large number of particles together with the resin can be seen to have advantages, it is not easy to achieve the requirements of recent years for the film with smelted particles High level of low gloss appearance. In addition, since the light transmittance of the particle-incorporated film is low, when the photocurable resin is used as the functional layer of the lamination, the curing becomes insufficient, and there is a problem that the application range is limited.

As a conventionally used matte transfer substrate, a polyester film containing inorganic particles or organic particles at a high concentration has been proposed (for example, Patent Documents 1 and 2). In addition, as a film having a highly matte appearance, a film in which a resin layer is provided on the surface by coating has been proposed (for example, Patent Document 3).

prior art literature Patent Literature

Patent Document 1 Japanese Patent Application Laid-Open No. 2016-97522

Patent Document 2 Japanese Patent Application Laid-Open No. 2014-24341

Patent Document 3 Japanese Patent Laid-Open No. 2005-24942

The films described in Patent Documents 1 and 2 are not designed to ensure transparency, and the variation in surface roughness cannot be sufficiently reduced; therefore, when a photocurable resin is used as a functional layer, there is a possibility that uniform transfer cannot be achieved. The subject of glossy surfaces.

In addition, the film described in Patent Document 3 has extremely low gloss and excellent appearance, but when used for transfer applications, coarse particles fall off, resulting in poor quality of the transfer surface and adhesion of particles. In addition, when the release layer is provided by coating, the laminated release layer fills the concave portion on the surface of the film to increase the gloss, so that the target matte appearance cannot be obtained without lowering the gloss after transfer.

The subject of the present invention is to solve the above-mentioned problems of the conventional technology. That is, the subject is to provide a transfer and shape that can uniformly transfer a low-gloss appearance when used as a transfer film, and also achieve a low-gloss appearance when a photocurable resin is used as a transfer material. It is a film with good suitability for processing steps that is not prone to problems such as particle shedding or chipping, while being fixed.

In order to solve the problem, the present invention adopts the following structure:

(1) A thin film having a surface roughness SRa of at least one side of 100 nm or more and 3000 nm or less, a variation of the aforementioned surface roughness SRa in the range of 20 cm×14 cm is 10% or less, and the parallel line transmittance ST320 of 320 nm is 30% above.

(2) The thin film according to (1), wherein the maximum peak height (SRp) and the maximum valley depth (SRv) of the surface having a surface roughness SRa of 100 nm or more and 3000 nm or less satisfy the following formula (II): 1≦1 SRp/SRv≦3…(II).

(3) The thin film according to (1) or (2), wherein the central surface area ratio (SSr) of the surface having a surface roughness SRa of 100 nm or more and 3000 nm or less satisfies the following formula (III): 30≦SSr≦ 60...(III).

(4) The thin film according to any one of (1) to (3), wherein the thickness change before and after the heat treatment at 100° C. for 10 minutes is 0.1% or more and 10% or less.

(5) The film according to any one of (1) to (4), which is a laminate film having a base material layer and a high-concentration particle-containing layer (layer A), wherein the entire layer A is 100% by mass The A layer contains 1 mass % or more and 40 mass % or less of particles having an average particle diameter of 1 μm or more and 10 μm or less.

(6) The film according to any one of (1) to (5), wherein the ST320 is 60% or more.

(7) The thin film according to any one of (1) to (6), wherein the variation of the ST320 in the range of 20 cm×14 cm of the thin film is 0.1% or more and 10% or less.

(8) The film according to any one of (1) to (7), wherein the film haze is 70% or less.

(9) The thin film according to any one of (1) to (8), wherein the surface free energy of the surface having the surface roughness SRa of 100 nm or more and 3000 nm or less is 44 mN/m or less.

(10) The film according to any one of (1) to (9), which is mainly composed of polyester.

(11) The film according to any one of (1) to (10), which is used for transfer applications.

(12) A laminate film having a low gloss layer with a glossiness of 30 or less on at least one surface of a base material layer, wherein the surface roughness SRa of the surface of the low gloss layer is 100 nm or more and 3000 nm or less, and the film has The variation of the surface roughness SRa in the range of 20 cm×14 cm is 10% or less, and the parallel line transmittance ST320 of 320 nm is 30% or more.

According to the present invention, when used as a transfer film, it is possible to provide a film excellent in transferability with a low-gloss appearance and process suitability. This film can be suitably used as a transfer film excellent in transferability with a matte appearance in the circuit formation step.

The form in which the invention is carried out

As one form of the thin film of the present invention, the surface roughness SRa of at least one side is 100 nm or more and 3000 nm or less, the variation of the surface roughness SRa in the range of 20 cm×14 cm is 10% or less, and the parallel lines of 320 nm penetrate. The rate ST320 is 30% or more of the film.

The resin used for the film of the present invention is not particularly limited, and for example, polyesters such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc., can be used. Polyacrylate, polyethylene, polypropylene, polyamide, polyimide, polymethylpentene, polyvinyl chloride, polystyrene, polymethyl methacrylate, polycarbonate, polyether ether ketone, poly Dust, polyether dust, fluororesin, polyether imide, polyphenylene sulfide, polyurethane, cyclic olefin resin, etc. Among them, polyester is preferably used as the main component from the viewpoints of handling properties or dimensional stability of the film, and economical efficiency at the time of production. The term "mainly composed of polyester" as used in the present invention means that 50% by mass or more of the resin constituting the film is polyester. Furthermore, when the film of the present invention is a laminate film comprising a substrate layer and a high-concentration particle-containing layer, it is preferable that both the substrate layer and the high-concentration particle-containing layer contain polyester as the main component. The polyester as used in the present invention refers to a general term for polymers whose main chain is mainly bound by ester bonds, and can generally be obtained by subjecting a dicarboxylic acid component and a diol component to a polycondensation reaction.

The dicarboxylic acid component used here includes terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylenedicarboxylic acid, and diphenoxyethane Aromatic dicarboxylic acids such as dicarboxylic acid, 5-sodium sulfone dicarboxylic acid, fatty acids such as oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid, and fumaric acid Each component, such as alicyclic dicarboxylic acid such as 1,4-cyclohexanedicarboxylic acid, oxycarboxylic acid such as p-hydroxybenzoic acid, and the like. Moreover, as a dicarboxylate derivative component, the ester product of the above-mentioned dicarboxylate compound, for example, dimethyl terephthalate, diethyl terephthalate, 2-hydroxyethyl methyl terephthalate, 2-hydroxyethyl terephthalate, , Each component of dimethyl 6-naphthalate, dimethyl isophthalate, dimethyl adipate, diethyl maleate, and dimethyl dimer acid. Regarding the polyester resin constituting the resin film of the present invention, from the viewpoint of heat resistance and productivity, the ratio of terephthalic acid and/or naphthalenedicarboxylic acid in the total dicarboxylic acid component is preferably 95 mol% or more, more preferably is more than 98 mol%.

Moreover, as a glycol component, ethylene glycol, 1, 2- propylene glycol, 1, 3- propylene glycol, 1, 3- butanediol, 1, 4- butanediol, 1, 5- pentanediol, 1 ,6-hexanediol, aliphatic dihydroxy compounds such as 2,2-dimethyl-1,3-propanediol, polyoxyethylene such as diethylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol Each component, such as alicyclic dihydroxy compounds, such as alkanediol, 1, 4- cyclohexane dimethanol, spiroglycol, and aromatic dihydroxy compounds, such as bisphenol A and bisphenol S. Among them, ethylene glycol, 1,4-butanediol, 2,2-dimethyl-1,3-propanediol, and 1,4-cyclohexanedimethanol are preferably used from the viewpoint of moldability and handleability. of the ingredients. In the polyester resin constituting the resin film of the present invention, it is preferable from the viewpoints of heat resistance and productivity that the ratio of ethylene glycol in the total glycol components is 65 mol % or more. These dicarboxylic acid components and diol components may be used in combination of two or more.

The film of the present invention needs to have a surface roughness SRa of at least 100 nm or more and 3000 nm or less on one side from the viewpoint of transferability of a matte appearance. When the surface roughness SRa is less than 100 nm, it is difficult to obtain sufficient matte transferability, and when the surface roughness SRa is more than 3000 nm, the strength of the film decreases. From the viewpoints of matte transferability and film strength, the surface roughness SRa of at least one side is more preferably 200 nm or more and 2000 nm or less, and more preferably 300 nm or more and 2000 nm or less.

In the present invention, the method for setting the surface roughness SRa of at least one side to 100 nm or more and 3000 nm or less is not particularly limited. For example, the method of containing a particle|grains in a high density|concentration in a film, the method of transcribe|transferring a shape to a film surface by embossing, etc. are mentioned. When the surface roughness SRa of at least one side is in the above range according to the method of containing the particles in a high concentration in the film, from the viewpoint of both the film strength and the surface roughness, it is made to have a base material layer and a high concentration of particles. In the layered film of the particle layer (layer A), the particles contained in the layer A preferably have an average particle diameter of 1 μm or more and 10 μm or less; the content of the entire A layer is 100 mass %, and its content is preferably 1 mass % or more and 40 mass % the following. The content of the particles contained in the A layer is more preferably 3 mass % or more and 35 mass % or less, and more preferably 5 mass % or more and 30 mass % or less. In addition, the average particle diameter of the particles contained in the A layer is preferably 2 μm or more and 10 μm or less, more preferably 3 μm or more and 9 μm or less, and most preferably 4 μm or more and 8 μm or less. In addition, the average particle diameter in this invention means the number average particle diameter D represented by D=ΣDi/N (Di: equivalent circle diameter of particle, N: number of objects).

As the particles used in the high-concentration particle-containing layer (layer A) of the present invention, both inorganic particles and organic particles can be applied. Inorganic particles and organic particles may be used in combination.

Here, the inorganic particles and organic particles to be used are not particularly limited. For example, as the inorganic particles, silica, aluminum silicate, alumina silicate, calcium carbonate, calcium phosphate, alumina, mica, clay, talc, and the like can be used. As the organic particles, particles containing styrene, polysiloxane, acrylic, methacrylic, polyester, and divinyl compounds as constituent components can be used. Among the inorganic particles, wet and dry silica, colloidal silica, aluminum silicate, etc. are preferably used. Among the organic particles, particles containing styrene, polysiloxane, acrylic, methacrylic, polyester, divinylbenzene, etc. as constituent components are preferably used. From the viewpoint of matte appearance and economy, it is particularly preferable to use silica, aluminum silicate, and aluminum silicate. In addition, these particles may be used in combination of two or more.

In addition, in the thin film of the present invention, the variation of the surface roughness SRa in the range of 20 cm×14 cm needs to be 10% or less for a surface having a surface roughness SRa of not less than 100 nm and not more than 3000 nm. The deviation of the surface roughness SRa in the present invention is for a sample of a size of 20 cm in length x 14 cm in width cut into a film at an arbitrary position, and is divided into 5 equal parts along the length direction and 4 equal parts along the width direction. The length is 4.0 cm x The surface roughness SRa of 20 samples with a width of 3.5 cm was calculated according to the method described later. If the deviation of the surface roughness SRa is more than 10%, the matte transferability will be uneven, and the appearance of the product will be deteriorated. From the viewpoint of the appearance of the matte preparation product, the variation in the surface roughness SRa is more preferably 8% or less, and most preferably 6% or less. As a result of diligent research conducted by the inventors of the present invention, it was found that when the film of the present invention is used as a transfer film, a surface roughness SRa having a variation of a certain level or more is excellent in releasability. So far, the mechanism by which this phenomenon is caused has not been elucidated, but it is presumed that if there is a certain degree of variation in the surface roughness SRa and a large number of starting points for causing peeling are formed, the peelability will be good. Therefore, from the viewpoint of peelability, the variation in the surface roughness SRa is preferably 0.1% or more, more preferably 0.5% or more, and still more preferably 1% or more.

In the present invention, there is no particular limitation on the method of setting the variation of the surface roughness SRa in the range of 20 cm×14 cm of the surface with the surface roughness SRa of 100 nm to 3000 nm and the above range, for example, it is preferable to use a A layered film with a high-concentration particle-containing layer (layer A) such that the layer thickness TA (μm) of the layer A and the average particle diameter DA (μm) of the particles contained in the layer A satisfy the following formula (I) method.

0.8≦DA/TA≦10.0…(I)

By satisfying the formula (I), the surface roughness SRa can be further controlled to a certain extent uniformly in the shape of the particles on the surface, and the variation of the surface roughness SRa can be more easily controlled within the above-mentioned range. From the viewpoint of the variation of the surface roughness SRa and the suppression of particle falling off, the formula (I') is more preferably satisfied, the formula (I") is further satisfied, and the expression (I''') is best satisfied.

1.1≦DA/TA≦10.0…(I’)

1.2≦DA/TA≦8.0…(I”)

1.3≦DA/TA≦6.0…(I''').

When the film of the present invention is a laminate film having a substrate layer and a high-concentration particle-containing layer (layer A), layer A may be disposed on only one surface of the substrate layer, or may be disposed on both surfaces.

When the film of the present invention is used for transfer purposes, a functional layer is provided on the surface of the film of the present invention whose surface roughness SRa is 100 nm to 3000 nm (the surface roughness SRa of the transfer film of the present invention is 100 nm to 3000 nm). The material layer to be transferred in the shape of the film surface below). As the functional layer, a photocurable resin is preferably used. In order to sufficiently secure the curability of the functional layer composed of the photocurable resin, the parallel line transmittance ST320 at 320 nm of the film of the present invention needs to be 30% or more. If ST320 is less than 30%, the curability of the photocurable resin will be insufficient, and the properties of transferring the matte appearance will be deteriorated. If ST320 is 45% or more, it is more preferable, and if it is 60% or more, it is the best. From the viewpoint of the handleability of the film, ST320 is preferably 95% or less. In addition, in terms of transmittance, there are generally (i) the transmittance taking into account reflection and scattering (the total light transmittance measured by collecting the transmitted light with an integrating sphere), (ii) not taking into account reflection, Scattered transmittance (parallel line transmittance measured with parallel rays). In order to sufficiently secure the curability of the functional layer made of the photocurable resin, it is necessary to increase the parallel line transmittance of (ii).

Furthermore, in the film of the present invention, in order to reduce the variation in the transferability of the matte surface, the variation of ST320 is preferably 10% or less in the range of 20 cm×14 cm of the film. By making the variation of ST320 10% or less, the curability of the resin when the photocurable resin is applied is more uniform, and the variation of the matte transferability can be suppressed. The deviation of ST320 is the same as the evaluation of the deviation of the above-mentioned surface roughness SRa. For a sample with a length of 20cm × a width of 14cm, cut the film at any position into 5 equal parts along the length direction and 4 equal parts along the width direction. The size of the growth 4.0 cm x the width 3.5 cm was calculated from the parallel line transmittance ST320 of the sample at 320 nm, respectively. The deviation of ST320 in the range of the film 20cm×14cm is preferably 8% or less, and most preferably 6% or less. On the other hand, as a result of diligent research conducted by the inventors of the present invention, it has been found that when the film of the present invention is used as a transfer film, those having a variation of ST320 to a certain extent or more are excellent in peelability. So far, it is not clear what mechanism causes this phenomenon, but if there is a certain degree of deviation in ST320, the functional layer composed of photocurable resin will have a hardened part and a hardened part, resulting in a higher hardness. High part and low part. As a result, in the functional layer composed of the photocurable resin, the portion with high hardness in the vicinity of the portion with low hardness becomes a starting point for peeling, and it is presumed that the peelability is good. Therefore, from the viewpoint of peelability, the variation of ST320 is preferably 0.5% or more, more preferably 1% or more.

Moreover, the film haze of the film of the present invention is preferably 70% or less. When the haze of the film is 70% or less, the defect inspection property can be greatly improved under the constitution of the layered product laminated on the transfer target material, which is preferable.

In the present invention, as a method for making the parallel line transmittance ST320 at 320 nm to be 30% or more, a laminate film having a base material layer and a high-concentration particle-containing layer (layer A) is prepared, and only the high-concentration particle-containing layer is formed. A method in which the layer (layer A) is arranged on one surface of the base material layer, and the particle concentration in the base material layer is less than 1 mass % with respect to the whole base material layer. The particle concentration in the base material layer is preferably less than 0.5 mass % with respect to the entire base material layer. Furthermore, it is preferable to reduce the voids around the particles of the high-concentration particle-containing layer (layer A). For example, when both the base material layer and the high-concentration particle-containing layer (layer A) contain polyester to form a biaxially stretched polyester film, in order to suppress the generation of voids in the high-concentration particle-containing layer (layer A) during stretching as described later, More preferably, a method of improving the stretchability of the high-concentration particle-containing layer (layer A), a method of reducing voids by performing a high-temperature treatment in a heat treatment step after stretching, which will be described later, and the like are preferably used. The high-concentration particle-containing layer (layer A) contains copolymerized polyethylene terephthalate resin, polytrimethylene terephthalate resin and/or its copolymer, poly(terephthalic acid) in order to improve its stretchability. Butylene diester resins and/or copolymers thereof are preferred.

Moreover, in this invention, as the method of controlling the dispersion|variation of ST320 in a film 20cm*14cm range, adjustment of the stretching conditions in a film stretching process is mentioned. For example, when the film of the present invention is used as a biaxially stretched polyester film, at least one of the stretching in the longitudinal direction and the stretching in the width direction is preferably two or more staged stretching. In the case of simultaneous biaxial stretching in the longitudinal direction and the width direction, it is also preferable to employ two or more stage stretching. In the present invention, the two-stage or more staged stretching means that two or more stretching sections are set, and different stretching conditions are used in the two sections. It is presumed that by performing the stepwise stretching in two or more stages, the strain in the vicinity of the particles can be reduced, whereby the stretching unevenness can be suppressed, and the variation of ST320 can be controlled within a preferable range. Moreover, it can also be mentioned as a preferable method to make a drawing speed into a suitable range mentioned later. The stretching interval is preferably above 2 intervals and below 3 intervals.

Moreover, in this invention, in order to make a film haze into 70% or less, the method of controlling the amount of particle|grains contained in a film is mentioned. When the film of the present invention is a laminate film having a substrate layer and a high-concentration particle-containing layer (layer A), the particle content in the substrate layer is preferably less than 3% by mass relative to the entire substrate layer.

In the film of the present invention, from the viewpoints of matte transferability and film releasability after transfer, the maximum peak height (SRp) and the maximum valley depth (SRv) of the surface with a surface roughness SRa of not less than 100 nm and not more than 3000 nm preferably satisfy the following requirements: Formula (II) is described.

1≦SRp/SRv≦3…(II)

Since the maximum peak height (SRp) and maximum trough depth (SRv) of the surface satisfy the formula (II), it has a mountain shape sufficient to transfer a matte tone, and can well control the transfer peelability from the functional layer. The maximum peak height (SRp) and maximum trough depth (SRv) of the surface preferably satisfy the following formula (II)', and best satisfy the formula (II)".

1.1≦SRp/SRv≦2.9…(II)’

1.2≦SRp/SRv≦2.8…(II)”

The method for making the maximum peak height (SRp) and the maximum trough depth (SRv) of the surface satisfy the formula (II) is not particularly limited. For example, when the film of the present invention is a laminate film having a substrate layer and a layer containing high-concentration particles (layer A), it is preferable to adopt a method of reducing the particle size of the particles contained in the layer A and increasing the particle concentration. A method of controlling the shape of a film surface. The average particle diameter of the particles contained in the A layer is preferably less than 2.5 μm, and the content is preferably 3 to 40 mass % based on 100 mass % of the entire A layer. The average particle diameter of the particles contained in the A layer is more preferably less than 2.3 μm. Moreover, the particle content of the A layer is more preferably 5 mass % or more and 30 mass % or less.

Furthermore, in the film of the present invention, from the viewpoint of making the transfer releasability from the functional layer more favorable, the central area ratio (SSr) of the surface having a surface roughness SRa of 100 nm or more and 3000 nm or less preferably satisfies the following formula (III).

30≦SSr≦60…(III)

The central surface area ratio (SSr) is obtained by the measurement method described later, and is an index indicating the ratio of the convex portion of the central surface to the reference area. The larger the value is, the smoother the protrusions of the protrusions on the film surface are; the smaller the value is, the steeper the protrusions on the film surface are. When the center surface area ratio (SSr) of the surface satisfies the formula (III), the matte surface can be adjusted and transferred to the surface asperity shape, and the transferability from the functional layer can be well controlled. The central surface area ratio (SSr) of the surface preferably satisfies the formula (III)', and best meets the formula (III)".

30≦SSr≦55…(III)’

35≦SSr≦55…(III)”

The method for making the central surface area ratio (SSr) of the surface satisfy the formula (III) is not particularly limited. For example, when the film of the present invention is a laminate film having a substrate layer and a layer containing high-concentration particles (layer A), it is preferable to reduce the particle size of the particles contained in the A layer, increase the particle concentration, and make the A layer's particle size smaller. A method in which the thickness becomes less than or equal to a certain value. Preferably, the average particle diameter of the particles contained in the A layer is less than 2.5 μm, and the content of the particles contained in the A layer is preferably 3 mass % or more and 40 mass % or less based on 100 mass % of the entire A layer, and the layer thickness of the A layer is set. less than 3μm. In addition, the ratio (DA (μm)/TA (μm)) of the average particle diameter of the particles contained in the A layer to the laminate thickness of the A layer is preferably 0.8 or more and 10 or less, and more preferably 1.1 or more and 10 or less. , if it is 1.3 or more and 6 or less, it is the best.

In the laminated film of the present invention, it is preferable to control the thickness change before and after the heat treatment at 100° C. for 10 minutes to 0.1% or more and 10% or less. When the film of the present invention is used as a transfer film, a functional layer is provided on the surface of the film having a surface roughness SRa of not less than 100 nm and not more than 3000 nm (for transferring the film of the present invention, the surface roughness SRa is not less than 100 nm). 3000nm or less film surface shape of the transfer material layer), and when the functional layer is provided, a thermal load is applied when the functional layer is coated and dried. By controlling the dimensional change in the thickness direction of the film when thermal load is applied, that is, the thickness change before and after heat treatment at 100°C for 10 minutes, to be less than 10%, the film is less likely to fall into the functional layer when the functional layer is coated and dried, and Transfer releasability can be better controlled. The thickness change before and after the heat treatment at 100° C. for 10 minutes is more preferably 8% or less, and still more preferably 6% or less. On the other hand, as a result of intensive research conducted by the inventors of the present invention, when the film of the present invention is used as a transfer film, when a thermal load is applied, a dimensional change in the film thickness direction to a certain extent or more is excellent in releasability. So far, it is not clear what mechanism causes this phenomenon, but we speculate that those with a certain degree of dimensional change in the thickness direction of the film when a thermal load is applied are more likely to have parts where the film is greatly entrapped into the functional layer and slightly entrapped. As a result, at the site of the functional layer, near the site where the film is largely entrapped in the functional layer, and the site where the film slightly entrapped in the functional layer becomes a starting point for peeling. Therefore, from the viewpoint of peelability, the thickness change before and after the heat treatment at 100° C. for 10 minutes is preferably 0.5% or more, more preferably 1% or more. As a method of controlling the thickness change before and after the heat treatment at 100°C for 10 minutes, for example, when the film of the present invention is used as a biaxially stretched polyester film, the stretching conditions in the film stretching step can be adjusted. For example, the stretching ratio (area ratio = longitudinal stretching ratio × width direction stretching ratio) is increased to 14 times or more, preferably 16 times or more, and the heat treatment temperature after stretching is set to 230° C. A preferable method is above, preferably 235°C or more and 250°C or less.

From the viewpoint of transferability, the film of the present invention preferably has a surface free energy of 44 mN/m or less of a surface having a surface roughness SRa of 100 nm or more and 3000 nm or less. By setting the surface free energy to be 44 mN/m or less, since the releasability with the transfer material can be improved, transfer and peeling can be facilitated, and the transferability can be improved. The surface free energy on the layer A side is more preferably 42 mN/m or less, and more preferably 15 mN/m or more and 40 mN/m or less.

The method for setting the surface free energy of the surface of the thin film of the present invention having a surface roughness SRa of not less than 100 nm and not more than 3000 nm in the aforementioned range is not particularly limited. The method of mold release agent, such as a fluorine-type compound, the method of implementing mold release coating, etc. In addition, when the film of the present invention is a laminate film having a base material layer and a high-concentration particle-containing layer (A layer), it is preferable to add the aforementioned release agent to the high-concentration particle-containing layer (A layer), or to the aforementioned ( A layer) The method of performing mold release coating on the surface.

In the present invention, when the surface of the high-concentration particle-containing layer (layer A) is subjected to release coating, in order to make the concavities formed by the particles contained in the high-concentration particle-containing layer (layer A) appear on the release coating On the surface of the layer, the thickness of the release coating is preferably 0.01 μm or more and 3 μm or less, more preferably 0.02 μm or more and 2 μm or less, and even more preferably 0.03 μm or more and 1.5 μm or less. In addition, from the viewpoint of heat resistance during heating, it is preferable to contain a melamine resin and a mold release agent in the mold release layer. From the viewpoint of heat resistance and mold release stability, the content of the melamine resin in the mold release layer is preferably 50% by mass or more.

Examples of the melamine resin usable in the present invention include melamine formaldehyde resins, methylated melamine formaldehyde resins, butylated melamine formaldehyde resins, etherified melamine formaldehyde resins, epoxy-modified melamine formaldehyde resins, and other melamine formaldehyde resins, and urea melamine resins. resin, acrylic melamine resin, etc. Among them, melamine formaldehyde resin is preferred, and methylated melamine formaldehyde resin is particularly preferred because of moderate releasability. In addition, the mold release layer in the present invention preferably contains other adhesive resins in addition to the adhesive resin and the release agent from the viewpoints of film-forming properties and stretchability. As the adhesive resin, polyester-based resins, acrylic-based resins, and urethane-based resins are preferably used, and acrylic-based resins are particularly preferably used. Examples of acrylic resins include homopolymers or copolymers of alkyl (meth)acrylates, and (meth)acrylate copolymers having curable functional groups at the end of the side chain and/or main chain; As a functional group, a hydroxyl group, a carboxyl group, an epoxy group, an amine group, etc. are mentioned. Among them, an acrylic monomer copolymer obtained by copolymerizing an acrylic monomer and an acrylate having a sclerosing functional group at the end of a side chain and/or a main chain is preferable. Moreover, as a release agent contained in the release layer of this invention, a fluorine compound, a long-chain alkyl compound, a wax compound, etc. are mentioned, for example. These release agents may be used alone or in plural.

The fluorine compound that can be used in the present invention is a compound containing a fluorine atom in the compound. Examples thereof include perfluoroalkyl group-containing compounds, polymers of fluorine atom-containing olefin compounds, and aromatic fluorine compounds such as fluorobenzene. When the mold release film of the present invention is used for forming and simultaneous transfer foil applications, the fluorine compound is preferably a macromolecular compound in consideration of heat resistance and contamination because a high thermal load is applied during transfer.

The long-chain alkyl compound refers to a compound having a linear or branched alkyl group having 6 or more carbon atoms, particularly preferably 8 or more carbon atoms. Specific examples thereof include, without particular limitation, long-chain alkyl group-containing polyethylene resins, long-chain alkyl group-containing acrylic resins, long-chain alkyl group-containing polyester resins, long-chain alkyl group-containing amine compounds, Ether compounds containing long-chain alkyl groups, quaternary ammonium salts containing long-chain alkyl groups, etc. If the long-chain alkyl compound is a polymer compound, it is preferable to prevent the components derived from the release layer from sticking to the surface of the target substrate to be bonded when the release film is peeled off.

As the wax compound usable in the present invention, there are natural waxes, synthetic waxes, and waxes selected from waxes incorporating these. Natural wax refers to vegetable wax, animal wax, mineral wax and petroleum wax. Examples of the vegetable wax include candelilla wax, carnauba wax, rice bran wax, wood wax, and jojoba oil. Examples of animal waxes include beeswax, lanolin, and spermaceti. As the mineral-based wax, montan wax, ozokerite wax, and ozokerite wax are mentioned. As petroleum wax, paraffin wax, microcrystalline wax, and paraffin oil are mentioned. Examples of synthetic waxes include synthetic hydrocarbons, modified waxes, hydrogenated waxes, fatty acids, amides, amines, amides, esters, and ketones. As far as synthetic hydrocarbons are concerned, well-known ones are Fischer-Tropsch wax (also known as Sasol Wax), polyethylene wax, and also include low molecular weight polymers (specifically, polymers with a viscosity average molecular weight of 500 to 20,000). ) or lower polymers. That is, there are polypropylene, ethylene-acrylic acid copolymers, polyethylene glycol, polypropylene glycol, block or graft linkages of polyethylene glycol and polypropylene glycol. Examples of the modified wax include montan wax derivatives, paraffin wax derivatives, and microcrystalline wax derivatives. The derivatives referred to herein refer to compounds obtained by any one of purification, oxidation, esterification, saponification, or a combination thereof. Examples of the hydrogenated wax include hardened castor oil and hardened castor oil derivatives.

By dispersing these mold release agents uniformly on the surface of the mold release layer, the adhesion force and peeling force with the laminated layer and the peeled mold release layer can be adjusted to an appropriate range on the mold release layer. As a mold release agent, when a long-chain alkyl compound is used, it is preferable for the use of the present invention because the peeling force can be adjusted widely.

Next, an example of a laminate film having a base material layer and a high-concentration particle-containing layer (layer A) will be described with respect to the specific production method of the film of the present invention, but the present invention is not limited to the example.

When polyester resin is used for the base material layer and the high-concentration particle-containing layer (layer A) of the film of the present invention, they are supplied to each extruder and melt-extruded. At this time, the resin temperature is preferably controlled at 255°C to 295°C. Next, the removal of impurities and the equalization of the extrusion amount are carried out by a filter or a gear pump, respectively, and are co-extruded from a T-die onto a cooling drum to form a sheet to obtain a laminated sheet. At this time, by the electrostatic application method in which the cooling drum and the resin are electrostatically brought into close contact with the electrode using a high voltage, the casting method in which a water film is formed between the casting drum and the extruded polymer sheet, and the casting drum The temperature is the glass transition point of polyester resin ~ (glass transition point - 20 ℃) and the extrusion polymer is adhered, or a combination of these methods is used to make the sheet polymer closely adhere to the casting drum. Cool to solidify. Among these casting methods, when polyester is used, a method of applying static electricity is preferably used from the viewpoint of productivity and flatness.

The laminated film of the present invention is preferably a biaxially oriented film from the viewpoints of heat resistance and dimensional stability. The biaxially oriented film can be stretched in the longitudinal direction of the unstretched film by stretching in the width direction, or by the sequential biaxial stretching method in which the unstretched film is stretched in the longitudinal direction after being stretched in the width direction, or by It is obtained by stretching the film by a simultaneous biaxial stretching method or the like in which the longitudinal direction and the width direction of the film are continuously stretched at substantially the same time.

The stretching ratio in the stretching method is preferably 2.8 times or more and 5 times or less in the longitudinal direction, more preferably 2.9 times or more and 4.5 times or less. Also, the stretching speed is preferably 1,000%/min or more and 200,000%/min or less. Moreover, the stretching temperature in the longitudinal direction is preferably 70°C or higher and 90°C or lower. In addition, the stretching ratio in the width direction is preferably 2.8 times or more and 5 times or less, and more preferably 3 times or more and 4.5 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 laminated film of the present invention is preferably stretched in two or more stages from the viewpoint of controlling the variation of the parallel line transmittance ST320 of 320 nm in the range of 20 cm×14 cm of the film. In addition, the said draw ratio shows the total draw ratio of each direction.

Furthermore, heat treatment of the film is performed after the biaxial stretching. The heat treatment can be carried out by any conventionally known method, such as on heated rolls in an oven. This heat treatment is performed at a temperature of 120°C or higher and below the crystal melting peak temperature of the polyester, and in order to make the parallel line penetration rate ST320 at 320 nm to be 30% or higher, it is based on reducing the particle periphery of the high-concentration particle-containing layer (layer A). From the viewpoint of voids, the heat treatment temperature is preferably set to the melting point of the high-concentration particle-containing layer (layer A) -20°C or higher, melting point +10°C or lower, more preferably -10°C or higher, melting point -5°C or lower. The heat treatment time can be arbitrarily set within a range that does not deteriorate the characteristics, but is preferably 5 seconds or more and 60 seconds or less, more preferably 10 seconds or more and 40 seconds or less, and most preferably 15 seconds or more and 30 seconds or less. Furthermore, in order to ensure stable mold release properties, a mold release layer may be applied in-line to the surface of the A layer. As a method of disposing the coating layer in-line in the film production step, it is preferable to use a metering bar or a gravure plate after dispersing the coating layer composition in water on the film that has been at least uniaxially stretched A method of drying the coating agent while applying it uniformly with a roll or the like and extending it. In this case, the thickness of the mold release layer is preferably 0.02 μm or more and 0.1 μm or less. In addition, various additives such as antioxidants, heat-resistant stabilizers, ultraviolet absorbers, infrared absorbers, pigments, dyes, organic or inorganic particles, antistatic agents, crystal nucleating agents, etc. can also be added to the release layer.

In addition, as one form of the film of the present invention, there can be mentioned a laminate film having a low gloss layer having a glossiness of 30 or less on at least one surface of the substrate layer, wherein the surface of the low gloss layer surface is The roughness SRa is 100 nm or more and 3000 nm or less, the variation of the surface roughness SRa in the range of 20 cm×14 cm of the thin film is 10% or less, and the parallel line transmittance ST320 at 320 nm is 30% or more. By having a low gloss layer with a glossiness of 30 or less, when used as a transfer film, a low gloss appearance can be transferred. The glossiness of the low gloss layer is more preferably 25 or less, still more preferably 20 or less. The glossiness of the low-gloss layer can be controlled by including particles used in the high-concentration particle-containing layer (A), adjusting the surface roughness of the low-gloss layer, and the like. In this configuration, the low gloss layer is more preferably the high concentration particle-containing layer (A). In addition, the glossiness mentioned in this invention means the 60 degree specular glossiness calculated|required by the measuring method mentioned later.

The film of the present invention has a surface roughness SRa of at least 100 nm to 3000 nm on at least one side, a small deviation of the aforementioned surface roughness SRa in the range of 20 cm×14 cm, and a high transmittance of parallel lines at 320 nm. When a curable resin is used as a material to be transferred, transfer of a low gloss appearance and shape fixation can be sufficiently achieved. Therefore, it can be used as a transfer film excellent in transferability with a matte appearance in the circuit formation step.

[Example] (1) Composition of polyester

The polyester resin and film can be dissolved in hexafluoroisopropanol (HFIP), and the content of each monomer residue component or by-product diethylene glycol can be quantified using ¹ H-NMR and ¹³ C-NMR. If it is a laminated film, depending on the thickness of the laminated layer, each layer of the film is cut off, and the constituents of each layer are taken and evaluated. In addition, the composition of the film of the present invention is calculated by calculation from the mixing ratio at the time of film production.

(2) Intrinsic viscosity of polyester

The intrinsic viscosity of polyester resin and film is measured by dissolving polyester in o-chlorophenol at 25°C using an Oswald viscometer. If it is a laminated film, depending on the thickness of the laminated layer, cut off each layer of the film to evaluate the inherent viscosity of each layer.

(3) Film thickness

The thickness of the laminated film was measured using a dial thickness gauge (manufactured by Mitutoyo Co., Ltd.) having a flat tip and a diameter of 4 mm. The film thickness was measured at the center of the film, at positions 4 cm from the center of the film in the longitudinal direction (2 points), and at positions 4 cm in the width direction (2 points), and the average value was used as the film thickness.

(4) Thickness of each layer

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

(5) Average particle size of particles

From the laminated film, the resin constituting the film was removed by a plasma low-temperature ashing treatment method (PR-503 manufactured by Yamato Scientific) to expose the particles. This was observed with a transmission electron microscope (TEM H7100, manufactured by Hitachi, Ltd.), an image of the particles (the intensity of light formed by the particles) was connected to an image analyzer (QTM900, manufactured by Cambridge Instruments), and the observation position was changed so that the particles were The number-average particle diameter D obtained by the following numerical treatment was performed on 5,000 or more particles as the average particle diameter.

D=ΣDi/N

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

(6) Content of particles

1 g of the polymer was put into 200 ml of a 1N-KOH methanol solution, and heated to reflux to dissolve the polymer. To the dissolved solution, 200 ml of water was added, and then the liquid was loaded into a centrifugal separator to settle the particles, and the supernatant was removed. The particles were further washed with water and centrifuged, and the procedure was repeated twice. The particles thus obtained were dried and weighed to calculate the content of the particles.

(7) Surface roughness SRa, maximum peak height SRp, maximum trough depth SRv, central surface area ratio SSr

The size of cut length 4.0cm × width 3.5cm was taken as a sample, and the polyester film was measured according to JIS B0601-1994 according to the following conditions using a high-precision micro-shape measuring device (three-dimensional surface roughness meter) by the stylus method. surface morphology.

‧Measuring device: Three-dimensional micro-shape measuring device (ET-4000A manufactured by Kosaka Research Institute Co., Ltd.)

‧Analysis instrument: 3D surface roughness analysis system (TDA-31 type)

‧Contact: tip radius 0.5μm, diameter 2μm, made of diamond

‧Needle pressure: 100μN

‧Measuring direction: average after measuring the length direction of the film and the width direction of the film once each

‧X measuring length: 1.0mm

‧X travel speed: 0.1mm/s (measurement speed)

‧Y transition pitch: 5μm (measurement interval)

‧Number of Y lines: 81 (measurement number)

‧Z magnification: 20 times (vertical magnification)

‧Low range cutoff: 0.20mm

‧High domain cutoff: R+Wmm (roughness cutoff value) R+W means not cutoff.

‧Filter method: Gaussian space type

‧Leveling: Yes (tilt correction)

‧Reference area: 1mm ² .

The measurement was carried out under the above-mentioned conditions, and then the center plane average roughness SRa, the maximum peak height SRp, the maximum trough depth (SRv), and the center plane area ratio (SSr) were calculated using an analysis system.

(8) Variation of surface roughness SRa in the range of 20cm×14cm of the film

Cut the film at any position to a size of 20cm long (parallel to the length direction) x 14cm wide (parallel to the width direction) as a sample, and further divide the sample into 5 equal parts in the length direction and 4 in the width direction. Cut into a size of 4.0 cm in length x 3.5 cm in width (a total of 20 samples). This sample was calculated from each surface roughness SRa in the same manner as in (7), and the deviation was obtained as follows.

Deviation of surface roughness SRa (%)={(maximum-minimum)/average}×100

(9) Gloss

In accordance with the method specified in JIS-Z-8741 (1997), using a digital variable angle gloss meter UGV-5D manufactured by Suga Test Instruments, the 60° specular gloss was measured with N=3, and the average value was used as the gloss of the present invention. .

(10) 320nm parallel line transmittance ST320

Using a spectrophotometer U-3410 (manufactured by Hitachi, Ltd.), the parallel line transmittance was measured in the wavelength range of 320 nm. In addition, the measurement was performed by injecting light from the side of the surface having a small surface roughness (SRa) measured in (7). In the measurement system, each sample was prepared in the same manner as in (8), and the average of 20 measurement points in total was obtained as the parallel line transmittance ST320 of 320 nm.

(11) Deviation of the parallel line transmittance ST320 of 320 nm in the range of 20 cm × 14 cm of the film

Each sample was prepared in the same manner as in (8), the parallel line transmittance ST320 at 320 nm was calculated in the same manner as in (10) for a total of 20 measurement points, and the deviation was determined as follows.

ST320 deviation (%)={(maximum-minimum)/average}×100

(12) Thickness change before and after heat treatment at 100°C for 10 minutes

Cut the film at an arbitrary position to a size of 10 cm in length × 10 cm in width as a sample, and measure the center of the film, at positions 4 cm in the length direction from the center of the film (2 points), and in the width direction in the same manner as in (3). The thickness of the 5 points at the position of 4 cm (2 points) was taken as the average value of the film thickness before heat treatment. Thereafter, the sample was held in a hot air oven set at 100° C. for 10 minutes to perform heat treatment, and the thickness of the sample after the heat treatment was similarly measured at 5 points, and the average value was taken as the film thickness after heat treatment. From the obtained thickness before heat treatment and after heat treatment, the change in thickness was calculated as follows.

Thickness change (%)={|thickness after heat treatment-thickness before heat treatment|/thickness before heat treatment}×100

(13) Surface free energy

Four kinds of water, ethylene glycol, formamide, and diiodomethane were used as measurement liquids, and the contact angle meter (Model CA-D, manufactured by Kyowa Interface Science Co., Ltd.) was used to determine the contact angle between each liquid and the film surface. static contact angle. Each liquid was measured 5 times, the average contact angle (θ) and each component of the surface tension of the measurement liquid (j) were substituted into the following equations, and γ ^L , γ ⁺ , γ ⁻ Solve.

(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 ^- represent the surface free energy, long-distance force term, Lewis acid parameter, and Lewis base parameter of the film surface, respectively; and γj, γj ^L , γj ⁺ , and γj ^- respectively Indicates the surface free energy, long-distance force term, Lewis acid parameter, and Lewis base parameter of the measuring solution used. In addition, the surface tension of each liquid used here used the value proposed by Oss ("fundamentals of Adhesion", LHLee (Ed.), p153, Plenum ess, New York (1991).).

(14) Peelability [I]

The film was used by cutting out a length of 20 cm x a width of 14 cm. The following solution for forming a release layer is applied by gravure coating on the surface of the film whose SRa is 100 nm or more and 3000 nm or less (when the SRa on both sides is 100 nm or more and 3000 nm or less, the surface roughness (SRa) is small. Dry in an oven at 180°C for 20 seconds. Furthermore, the coating composition for hard-coat layer formation was apply|coated using a slot-die coater so that the thickness after drying might be 5 micrometers by controlling a flow rate, and it dried at 100 degreeC for 1 minute to remove a solvent, and obtained the laminated body with a hard-coat layer laminated|stacked.

The obtained film/release layer/hard coat layered product was heated to a temperature of 160°C using a press with both the upper die temperature and the lower die temperature. DU PONT-TORAY Kapton 500H/V)/laminated body/polyimide film with a thickness of 0.125mm (DU PONT-TORAY Kapton 500H/V)/aluminum plate with a thickness of 0.2mm The composition was carried out under the condition of 1.5MPa 1 hour heat pressing. After the hot pressing, the laminate/polyimide film was taken out, and 300 mJ/cm ² of ultraviolet rays were irradiated from the laminate side using a high-pressure mercury lamp to harden the hard coat layer to obtain a sample. This sample was subjected to a peeling test at the interface between the film and the release layer (film/(this interface)/release layer/hard coat layer), and the peelability was evaluated according to the following criteria.

(Solution for forming release layer)

It was prepared with a mass ratio of methylated melamine: amine p-toluenesulfonate: acrylic monomer copolymer = 20: 0.4: 1, and diluted with toluene.

(Coating composition for forming a 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.

(Evaluation standard)

A: Can be peeled off without resistance

B: Resistance is felt when peeling off, but peelable

C: Unable to peel.

(15) Peelability [II]

The film was used by cutting out a length of 20 cm x a width of 14 cm. The coating composition for forming a photosensitive polyimide layer, which is a photocurable resin, is applied by gravure coating on the surface of the film whose SRa is 100 nm or more and 3000 nm or less. (SRa) small surface), it dried at 90 degreeC for 60 second in an oven, and obtained the laminated body of a film/photosensitive polyimide layer. The obtained laminate was laminated with a polyimide film ("Kapton" (registered trademark) 500H/V, manufactured by DU PONT-TORAY) at 70°C/0.2MPa, and irradiated with 800 mJ/cm ² from the laminate side using a high-pressure mercury lamp. of ultraviolet rays. At this time, a half (length 20 cm x width 7 cm) portion of the sample was shielded from light (the shielded portion was not exposed to UV). The peeling strength between the film and the photosensitive polyimide layer was measured for the portion with UV exposure and the portion without UV exposure, respectively, and evaluated according to the following criteria. In addition, regarding the peel strength, the film/photosensitive polyimide laminate was made into a strip with a length of 15 cm x width of 5 cm, and the film and the photosensitive polyimide layer were forcibly peeled off at 180°. The test was measured at a peeling speed of 300 mm/min in a 25°C, 50% RH environment using a tensile tester (Tensilon UCT-100 manufactured by ORIENTEC). In addition, the average value of the strength between 50% and 100% of the measured length was taken as the peel strength.

A: The difference between the peel strength of the part with UV exposure and the part without UV exposure is less than 0.5N/50mm

B: The difference in peel strength between the UV-exposed portion and the UV-exposed portion is 0.5N/50mm or more and less than 1N/50mm

C: The difference in peel strength between the UV-exposed portion and the UV-exposed portion is 1N/50mm or more

D: Unable to peel off at least any of the UV-exposed part and the non-UV-exposed part.

(16) Peelability [III]

A laminate of the film/photosensitive polyimide layer was obtained in the same manner as in (15). About the obtained laminated body, the polyimide film ("Kapton" (registered trademark) 500H/V made by DU PONT-TORAY) was laminated|stacked at 70 degreeC/0.2MPa. Then, after heat-processing at 100 degreeC for 10 minutes, the ultraviolet-ray of 800mJ/cm< ² > was irradiated from the laminated body side using a high pressure mercury lamp. At this time, a half (length 20 cm x width 7 cm) portion of the sample was shielded from light (the shielded portion was not exposed to UV). For the UV-irradiated samples of the obtained laminate, the peel strength between the film and the photosensitive polyimide layer was measured for the UV-exposed portion and the UV-exposed portion, respectively, and evaluated according to the following criteria.

A: The difference between the peel strength of the part with UV exposure and the part without UV exposure is less than 0.5N/50mm

B: The difference in peel strength between the UV-exposed portion and the UV-exposed portion is 0.5N/50mm or more and less than 1N/50mm

C: The difference in peel strength between the UV-exposed portion and the UV-exposed portion is 1N/50mm or more

D: Unable to peel off at least any of the UV-exposed part and the non-UV-exposed part.

(17) The transferability, uniform and beautiful appearance of the matte finish

From the peeling surface side of the release layer obtained by the method of (14), a size of 20 cm in length x 14 cm in width was cut out as a sample, and the sample was further divided into 5 equal parts in the longitudinal direction and 4 in the width direction. It was equally divided into a size of 4.0 cm in length x 3.5 cm in width (20 samples in total). For each of the samples, the glossiness was measured in the same manner as in (9), and the average value was evaluated according to the following criteria.

(Transferability of matte appearance)

A: Glossiness is 10 or less

B: Glossiness exceeds 10 and is 20 or less

C: Glossiness exceeds 20 and is 30 or less

D: The glossiness exceeds 30.

(The appearance of matte tone is uniform and beautiful)

From the difference between the maximum value and the minimum value of 20-point glossiness, evaluation was performed according to the following criteria.

A: The difference between the maximum value and the minimum value of gloss is 2 or less

B: The difference between the maximum value and the minimum value of gloss exceeds 2 and is 4 or less

C: The difference between the maximum value and the minimum value of gloss exceeds 4.

(18) Haze

The film was cut into a 10 cm square, and the haze was measured using a haze meter NDH-5000 manufactured by Nippon Denshoku Co., Ltd. The measurement was carried out at three places, and the average value thereof was used as the haze in the present invention.

In addition, in each of the above measurements, when the length direction and width direction of the film to be measured are unknown, the direction having the largest refractive index in the film is regarded as the width direction, and the direction orthogonal to the width direction is regarded as the length direction.

(production of polyester)

The polyester resin used for film production is prepared as follows:

(polyester A)

Polyethylene terephthalate resin (intrinsic viscosity: 0.65) with 100 mol% of terephthalic acid as a dicarboxylic acid component and 100 mol% of ethylene glycol as a diol component.

(polyester B)

Copolymerized polyethylene terephthalate resin (intrinsic viscosity: 0.8) obtained by copolymerizing isophthalic acid in an amount of 20 mol % with respect to the dicarboxylic acid component.

(polyester C)

Polybutylene terephthalate resin (intrinsic viscosity 1.2) with 100 mol% of terephthalic acid as a dicarboxylic acid component and 100 mol% of 1,4-butanediol as a diol component.

(polyester D)

"Hytrel (registered trademark)" 7247 manufactured by DU PONT-TORAY.

(Particle Masterbatch E)

Polyethylene terephthalate particle masterbatch (intrinsic viscosity: 0.65) containing colloidal silica particles having an average particle diameter of 3 μm in polyester A at a particle concentration of 30% by mass.

(Particle Masterbatch F)

Polyethylene terephthalate particle master batch (intrinsic viscosity: 0.65) containing colloidal silica particles with an average particle diameter of 5 μm in polyester A at a particle concentration of 30% by mass.

(Particle Masterbatch G)

Polyethylene terephthalate particle masterbatch (intrinsic viscosity: 0.65) containing silicate alumina particles having an average particle diameter of 3 μm in polyester A at a particle concentration of 30% by mass.

(Particle Masterbatch H)

Polyethylene terephthalate particle master batch (intrinsic viscosity: 0.65) containing silicate alumina particles having an average particle diameter of 5 μm in polyester A at a particle concentration of 30% by mass.

(Particle Masterbatch I)

Polyethylene terephthalate particle masterbatch containing colloidal silica particles with an average particle size of 2.2 μm at a particle concentration of 30% by mass in polyester A (intrinsic viscosity: 0.65)

(Particle Masterbatch J)

Polyethylene terephthalate particle masterbatch (intrinsic viscosity 0.65) containing silicate alumina particles with an average particle diameter of 2.4 μm in polyester A at a particle concentration of 30% by mass

(Mold Release Coating Solution (Aqueous Dispersion))

The following crosslinking agent: adhesive resin: mold release agent: particle was mixed in a mass ratio of 60:23:17, respectively, and diluted with pure water to adjust the mass ratio of solid content to 1%.

‧Crosslinking agent: Methylated melamine/urea copolymerized cross-linking resin ("NIKALAC" (registered trademark) "MW12LF" manufactured by Sanwa Chemical Co., Ltd.)

‧Adhesive resin I: Acrylic monomer copolymer (manufactured by Nippon Carbide)

‧Mold release agent: put CF ₃ (CF ₂ ) _n CH ₂ CH ₂ OCOCH=CH ₂ (n=5~11, average of n=9) into a glass reaction vessel ) 80.0 g, 20.0 g of acetylacetoxyethyl methacrylate, 0.8 g of dodecanethiol, 354.7 g of deoxygenated pure water, 40.0 g of acetone, C ₁₆ H ₃₃ N(CH ₃ ) ₃ C11. 0 g and C ₈ H ₁₇ C ₆ H ₄ O(CH ₂ CH ₂ O) _n H (n=8) 3.0 g, add 0.5 g of azobisisobutyramidine dihydrochloride, and stir in nitrogen atmosphere while stirring. A copolymer emulsion obtained by subjecting it to a copolymerization reaction at 60°C for 10 hours.

Particles: An aqueous dispersion obtained by diluting silica particles with a number average particle diameter of 170 nm (“SNOWTEX” (registered trademark) MP2040, manufactured by Nissan Chemical Industries, Ltd.) with pure water to a solid content concentration of 40% by weight.

(Example 1)

The composition and the lamination ratio are as shown in the table. The raw materials were supplied to the extruder, and the extruder cylinder temperature was set to 270°C, the short tube temperature was set to 275°C, and the nozzle temperature was set to 280°C, and the resin temperature was set to 270°C. 280°C, discharged from T-die to a cooling drum controlled to 25°C to form sheets. At this time, electrostatic application was carried out using a wire electrode having a diameter of 0.1 mm, and it was brought into close contact with a cooling drum to obtain an unstretched sheet. Next, in the longitudinal direction, the stretching temperature is 85°C, the first stage is 1.5 times, and the stretching speed is 50,000%/min, and the stretching temperature is 88°C, the second stage is 2.2 times, and the stretching speed is 80,000%/min. Stretching was performed (total stretching ratio 3.3 times). After that, corona discharge treatment was performed, and a release coating solution (aqueous dispersion) was applied to the surface of the A layer side using a metering bar to a wet thickness of 13.5 μm, followed by a tenter-type transverse stretching machine in the width direction. The stretching temperature is 100°C, the first stage is 1.8 times, and the stretching speed is 30,000%/min, and the stretching temperature is 120°C, the second stage is 2 times, and the stretching speed is 40,000%/min. ( The total stretch ratio is 3.6 times). Then, it heat-processed at 235 degreeC in a tenter, and obtained the film of the film thickness of 16 micrometers (release coating layer: 0.04 micrometer, A layer: 3.5 micrometer, base material layer: 12.5 micrometer).

(Example 2)

A film having a film thickness of 25 μm was obtained in the same manner as in Example 1, except that the composition and the lamination ratio were changed as shown in the table.

(Example 3)

A film having a film thickness of 16 μm was obtained in the same manner as in Example 1, except that the composition and the lamination ratio were changed as shown in the table.

(Example 4)

A film having a film thickness of 25 μm was obtained in the same manner as in Example 1, except that the composition and the lamination ratio were changed as shown in the table.

(Example 5)

A film having a film thickness of 16 μm was obtained in the same manner as in Example 1, except that the composition and the lamination ratio were changed as shown in the table, and the mold release coating solution was not applied after stretching in the longitudinal direction.

(Example 6)

A film with a film thickness of 16 μm was obtained in the same manner as in Example 2, except that the stretching conditions in the longitudinal direction were set at 85° C. and 3.3 times, and the stretching conditions in the width direction were set at 100° C. and 3.6 times. film.

(Example 7)

A film having a film thickness of 16 μm was obtained in the same manner as in Example 1, except that the composition and the lamination ratio were changed as shown in the table, and the mold release coating solution was not applied after stretching in the longitudinal direction.

(Example 8)

A film having a film thickness of 19.5 μm was obtained in the same manner as in Example 1, except that the composition, composition, and lamination ratio were changed as shown in the table, and the mold release coating solution was not applied after stretching in the longitudinal direction.

(Example 9)

In addition to changing the composition and lamination ratio as shown in the table, the stretching temperature in the longitudinal direction was 85°C and the first stage was 1.6 times, and the stretching temperature was 88°C and the second stage was stretched by 2.4 times (total stretching). ratio of 3.8 times), and then stretched at a stretching temperature of 100°C and 1.9 times in the first stage in the width direction, and stretched at a stretching temperature of 120°C and stretched 2.2 times in the second stage (total stretching ratio 4.2 times) Except for this, a film having a film thickness of 14.5 μm (release coating layer: 0.03 μm, A layer: 2 μm, base material layer: 12.5 μm) was obtained in the same manner as in Example 1.

(Example 10)

A film having a film thickness of 14.5 μm was obtained in the same manner as in Example 9, except that the composition and the lamination ratio were changed as shown in the table.

(Example 11)

A film having a film thickness of 14.5 μm was obtained in the same manner as in Example 9, except that the composition and the lamination ratio were changed as shown in the table.

(Example 12)

A film having a film thickness of 14.5 μm was obtained in the same manner as in Example 9, except that the composition and the lamination ratio were changed as shown in the table.

(Example 13)

A film having a film thickness of 14.5 μm was obtained in the same manner as in Example 9, except that the composition and the lamination ratio were changed as shown in the table.

(Example 14)

A film having a film thickness of 14.5 μm was obtained in the same manner as in Example 9, except that the composition and the lamination ratio were changed as shown in the table.

(Example 15)

A film having a film thickness of 14.5 μm was obtained in the same manner as in Example 9, except that the composition and the lamination ratio were changed as shown in the table.

(Example 16)

A film having a film thickness of 9 μm was obtained in the same manner as in Example 4, except that the composition and the lamination ratio were changed as shown in the table.

(Example 17)

In addition to stretching at a stretching temperature of 85°C and 1.7 times in the first stage in the longitudinal direction, and stretching at a stretching temperature of 88°C and 2.4 times in the second stage (total stretching ratio of 4.1 times), the The stretching temperature was 100°C, the first stage was stretched by 1.9 times, the second stage was stretched at a stretching temperature of 120°C, and the second stage was stretched by 2.2 times (total stretching ratio was 4.2 times). A film having a film thickness of 14.5 μm (release coating layer: 0.03 μm, A layer: 2 μm, base material layer: 12.5 μm) was obtained in the same manner as in Example 11 except that the heat treatment was performed at °C.

(Example 18)

In addition to stretching in the longitudinal direction at a stretching temperature of 85°C and 1.2 times in the first stage, stretching at a stretching temperature of 86°C and 1.2 times in the second stage, and stretching at a stretching temperature of 87°C and 1.6 times in the third stage, The stretching temperature was 88°C, the fourth stage was stretched by 1.7 times (total stretching ratio was 3.9 times), and the stretching temperature was 100°C in the width direction, and the first stage was stretched by 1.2 times, and the stretching temperature was 110°C, The 2nd stage stretched 1.2 times and stretched at a stretching temperature of 115°C, the 3rd stage stretched 1.6 times, and the 4th stage stretched at 120°C and stretched 1.8 times (total stretching ratio 4.1 times) ), a film having a film thickness of 14.5 μm (release coating layer: 0.03 μm, A layer: 2 μm, base material layer: 12.5 μm) was obtained in the same manner as in Example 11.

(Comparative Example 1)

A film having a film thickness of 22.5 μm was obtained in the same manner as in Example 8, except that the composition and the lamination ratio were changed as shown in the table.

(Comparative Example 2)

A film having a film thickness of 25 μm was obtained in the same manner as in Example 4, except that the composition and the lamination ratio were changed as shown in the table.

(Comparative Example 3)

A film having a film thickness of 20.5 μm was obtained in the same manner as in Example 2, except that the composition and the lamination ratio were changed as shown in the table.

In addition, in the table|surface, the thin film surface whose surface roughness SRa is 100 nm or more and 3000 nm or less is described as A surface, and the thin film surface whose surface roughness SRa is not 100 nm or more and 3000 nm or less is described as B surface. In the case of a thin film whose surface roughness SRa is 100 nm or more and 3000 nm or less on both surfaces, the surface with the larger surface roughness is described as the A1 surface, and the surface with the lower surface roughness SRa is described as the A2 surface.

Industrial Availability

The film of the present invention has a surface roughness SRa of at least one side of 100 nm or more and 3000 nm or less, the deviation of the aforementioned surface roughness SRa in the range of 20 cm × 14 cm is small, and the parallel line transmittance of 320 nm is high. Therefore, when using light When a curable resin is used as a material to be transferred, transfer of a low gloss appearance and shape fixation can be sufficiently achieved. Therefore, it can be used as a transfer film excellent in transferability with a matte appearance in the circuit formation step.

Claims (10)

A laminated film having a low gloss layer (A layer) with a glossiness of 30 or less on at least one surface of a base material layer, wherein the surface roughness SRa of the surface of the A layer is 100 nm or more and 3000 nm or less, and 20 cm of the laminated film is The deviation of the surface roughness SRa of the surface of the A layer in the range of ×14cm is 10% or less, the parallel line transmittance ST320 of the laminated film at 320nm is 30% or more, and the deviation of the ST320 in the range of 20cm × 14cm of the laminated film 0.1% or more and 10% or less. The laminated film of claim 1, wherein the maximum peak height (SRp) and the maximum valley depth (SRv) of the surface with a surface roughness SRa of 100 nm or more and 3000 nm or less satisfy the following formula (II): 1≦SRp/SRv≦ 3...(II). The laminated film of claim 1 or 2, wherein the surface roughness SRa is 100 nm to 3000 nm and the central surface area ratio (SSr) of the surface satisfies the following formula (III): 30≦SSr≦60...(III ). According to the laminated film of claim 1 or 2, the thickness change before and after the heat treatment at 100° C. for 10 minutes is 0.1% or more and 10% or less. The laminated film according to claim 1 or 2, wherein the A layer as a whole is 100 mass %, and the A layer contains 1 mass % to 40 mass % of particles with an average particle diameter of 1 μm to 10 μm. The laminated film of claim 1 or 2, wherein the ST320 is 60% or more. The laminated film of claim 1 or 2, wherein the haze of the laminated film is 70% the following. The laminated film according to claim 1 or 2, wherein the surface free energy of the surface having the surface roughness SRa of 100 nm or more and 3000 nm or less is 44 mN/m or less. The laminated film of claim 1 or 2 is mainly composed of polyester. The laminated film of claim 1 or 2 is used for transfer printing.