JP2011069995A - Antireflection film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antireflection film having good post-processability, high transparency, and high added value enduring various use environments. <P>SOLUTION: In the antireflection film, a hard coat layer made of photo-setting resin with a thickness of ≥1.5 μm and ≤6 μm and a total light transmittance of ≥89%, and an antireflection layer of four or more layers where high refraction material layers and low refraction layers are alternately stacked are stacked on at least one surface of a polyethylene terephthalate film (transparent base material film) with a thickness of ≥70 μm and ≤200 μm, a haze of ≤0.5%, and a total light transmittance of ≥88%. The antireflection film has a haze of ≤0.3%, a total light transmittance of ≥92%, a luminous reflectance of ≤0.9%, and a water vapor transmission rate of ≤2.0 g/m<SP>2</SP>/day. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an antireflection film that has good post-processability, high transparency, and can withstand various use environments.

  In an optical display device such as an LCD, CRT, or plasma display panel, an antireflection film that prevents reflection of external light such as sunlight or a fluorescent lamp is often used. In particular, for outdoor use where the reflection of outside light is large, an antireflection film having a reflectance close to zero is required.

  In general, the antireflection film uses a dry coating technique capable of forming a thin film having a thickness of several nanometers. Among these, the sputtering method is a thin film with higher visibility than other dry coating methods such as vapor deposition, ion plating, and CVD because it has higher film thickness uniformity and fewer defects such as pinholes. Can be formed. In addition, since a dense film can be formed, it is possible to form a thin film with extremely excellent mechanical properties.

  The antireflection film is often used in LCD applications, and an antireflection layer configuration in which the antireflection film is laminated on a protective film of a polarizing plate is common. A triacetyl cellulose (TAC) film is used as a protective film for this polarizing plate, that is, a base material for an antireflection film, because of its good hygroscopicity and very high transparency.

  However, when this TAC film is used for purposes other than LCD applications, although it has a great advantage of high transparency, (A) it is prone to appearance defects such as discoloration and corrosion due to hydrolysis, etc., and environmental durability Is bad. (B) The workability in the subsequent process is poor. (C) There is a problem that it is difficult to supply other than LCD applications. Therefore, in the case of use in LCD applications, development of an antireflection film having transparency and good post-processability using a substrate other than TAC is desired.

  Of course, an antireflection film using a substrate other than TAC, particularly polyethylene terephthalate (PET) has been proposed. For example, there are Patent Document 1 and Patent Document 2 as patents using a PET film. In general, dry coating methods, especially sputtering methods, have high film thickness uniformity, as described above, so that reflection with extremely low reflectivity based on a dense optical design with multiple layers stacked. Preventive film can be made. The price is that the process cost is high.

  For this reason, the price is higher and the price is higher than that of the antireflection film prepared by the wet coating method. Therefore, even if a PET film or the like that is inferior in optical performance is used as a base material compared to TAC, etc., there is currently little demand, and it is necessary to consider various application developments other than applications such as liquid crystal displays so far There is.

Japanese Patent No. 3141129 JP-A-9-193328

  In view of the above, even if a polyethylene terephthalate film (PET film) is used as a base material, it is an antireflection film having extremely high transparency and excellent mechanical properties. It is easy to use in various applications.

  In addition, it has high value-added performance that is resistant to deterioration at daily living levels such as water wetting, dirt, and wear, and since the film produced is a dense film, it has a film with high water vapor barrier performance. An object was to form an antireflection film.

In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that a hard coat layer and an antireflection layer are sequentially laminated on at least one surface of a transparent substrate, and the antireflection layer is made of a highly refractive material. In the antireflection film in which the thin film of the outermost layer of the antireflection layer is a low refractive index layer in a laminate of four or more layers in which layers and low refractive index layers are alternately laminated,
(A) The thickness of the transparent substrate is 70 μm or more and 200 μm or less, the haze is 0.5% or less, and the total light transmittance is 88% or more,
(B) The thickness of the hard coat layer is 1.5 μm or more and 6 μm or less,
(C) The total thickness of the antireflection layer is 100 nm or more and 300 nm or less,
(D) The haze of the antireflection film is 0.3% or less, the total light transmittance is 92% or more, the luminous reflectance is 0.9% or less, and the water vapor transmission rate is 2.0 g / m ² /. It is an antireflection film characterized by being not more than day.

  The invention according to claim 2 is the antireflection film according to claim 1, wherein the transparent substrate is a polyethylene terephthalate film.

  The invention according to claim 3 is characterized in that the low refractive index layer of the antireflection layer is silicon oxide and the high refractive index layer is niobium oxide. It is.

  In addition, as an invention according to claim 4, between the hard coat layer and the antireflection layer, a metal, an alloy composed of two or more metals, a metal compound, or a mixture thereof, 4. The antireflection film according to claim 1, wherein a primer layer comprising one or more layers is provided.

  The invention according to claim 5 is the antireflection film according to any one of claims 1 to 4, wherein an antifouling layer containing a fluorine compound is provided on the surface of the antireflection layer.

According to a sixth aspect of the present invention, a hard coat layer and an antireflection layer are sequentially laminated on at least one surface of a transparent substrate, and the antireflection layer comprises a high refractive material layer and a low refractive index. In a laminate of four or more layers in which layers are alternately stacked, the outermost thin film of the antireflection layer is a low-refractive index layer manufacturing method,
Laminating the antireflection layer by sputtering;
Laminating the antifouling layer by vacuum deposition;
It is a manufacturing method of the antireflection film characterized by comprising.

  By using the antireflection film of the present invention, according to the invention described in claim 1, it has high durability in daily living environment, high transparency, and mechanical properties such as scratch resistance test and pencil hardness test. Can be obtained.

According to the invention described in claim 2, when the thickness of the polyethylene terephthalate film is 100 μm, the water vapor transmission rate is 6.5 g / m ² / day at a temperature of 40 ° C. and a relative humidity of 90%. The film can be more difficult to transmit, and when used in an antireflection film, high water vapor barrier performance can be obtained.

  Further, according to the invention described in claim 3, by laminating the film on the film described in claim 2, it is possible for water vapor to be more difficult to permeate the film.

  Moreover, according to the invention of Claim 4, the adhesiveness of a hard-coat layer and an antireflection layer can be improved.

  Further, according to the invention of claim 5, by using the effects of claims 1 to 4, surface contamination such as fingerprints, sweat, makeup, oil, water droplets and the like on the outermost surface is difficult to be attached, and further, contamination is not caused. Even when attached, the wiping performance can be improved.

  In addition, according to the invention described in claim 6, by forming the antireflection layer by the dry coating method of the sputtering method, the film thickness uniformity is high, and there are few defects such as pinholes, so the visibility is excellent. A thin film having excellent mechanical properties such as scratch resistance can be formed. In addition, since the film formed by controlling the pressure by sputtering forms a dense film, by forming a material mainly containing a fluorine compound that can obtain high water vapor barrier performance by vacuum deposition, A uniform and thin film can be formed.

It is sectional drawing of the antireflection film of one Example of this invention.

  Embodiments of the present invention will be described below.

  FIG. 1 is a cross-sectional view showing an embodiment of the antireflection film of the present invention. In FIG. 1, in the antireflection film (100) of the present invention, a hard coat layer (2), a primer layer (3), and an antireflection layer (4) are sequentially laminated on a transparent substrate (1). Further, an antifouling layer (5) is laminated on the antireflection layer (4).

  As the transparent substrate (1) in the present invention, polyethylene terephthalate (polyethylene terephthalate) is a kind of polyester and is often referred to as polyethylene terephthalate in English reading. Therefore, in the present invention, it is referred to as polyethylene terephthalate, polyethylene terephthalate, or PET.) A film is used.

  The thickness of the transparent substrate (1) may be appropriately selected according to the intended use, but usually a thickness of 70 μm or more and 200 μm or less is used. Furthermore, the thing of 75 micrometers or more and 100 micrometers or less is preferable on optical characteristics or processing handling.

  In the present invention, the PET film as the transparent substrate (1) may contain additives such as a plasticizer, an ultraviolet absorber and a deterioration preventing agent, but it is necessary to select a highly transparent film. Therefore, an additive or the like in the form of a particle is not preferable because it lowers the light transmittance and the straightness of light and lowers the transparency. As far as possible, particulate additives inside should be avoided. In terms of handling, an easy-adhesion layer or the like is necessary, but it is necessary to coat the PET outside with as little surface roughness as possible. Further, the transparency of the film can be determined by the values of haze and light transmittance. In the present invention, a PET film having a haze of 0.5% or less and a total light transmittance of 88% or more is used.

  On the transparent base material (1), a hard coat layer (2) for sufficiently exhibiting the mechanical strength of the antireflection layer (4) is provided. As the hard coat layer (2) in the present invention, a photocurable resin that is cured by using ionizing rays or ultraviolet rays is used, and ultraviolet curable acrylic esters, acrylamides, methacrylic esters, methacrylamide, and the like are used. Acrylic resins, organosilicon resins, and polysiloxane resins are most suitable. A polymerization initiator may be added to these materials in order to improve curability. When having an easy-adhesion layer on one side of the PET film, it is preferable to coat HC on the easy-adhesion side. It has the effect of lowering the haze and further increasing the adhesion between the hard coat and the PET film.

  Moreover, as a coating method of the hard coat layer, a wet film forming method is generally used, and a roll coater, a reverse roll coater, a gravure coater, a micro gravure coater, a knife coater, a bar coater, a wire bar coater, a die coater, and a dip coater. A coating method using can be used.

  Moreover, as a hardening method of a hard-coat layer, an ultraviolet-ray and an electron beam can be used as ionizing radiation. In the case of ultraviolet curing, a light source such as a high pressure mercury lamp, a low pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a carbon arc, or a xenon arc can be used. In the case of electron beam curing, electron beams emitted from various electron beam accelerators such as cockloftwald type, bandegraph type, resonant transformer type, insulated core transformer type, linear type, dynamitron type, and high frequency type can be used. .

The thickness of the hard coat layer (2) is preferably a physical film thickness of 1.5 μm or more and 6 μm or less. When the thickness of the hard coat layer (2) is 1.5 μm or less, the mechanical strength performance is difficult to be obtained, and the ultraviolet irradiation energy may exceed the film thickness, resulting in poor curing.
If the thickness is 6 μm or more, hard coat cracks are likely to occur due to bending or pulling of the film, resin shrinkage at the time of curing may occur, and curling (warping) of the film may occur. Becomes worse.

  In the antireflection film (100) of the present invention, since the antireflection layer is extremely thin, the hardness of the entire antireflection film layer is easily affected by the hardness of the hard coat as the underlayer. Therefore, it is necessary to select a hard coat layer having as high mechanical strength as possible. In the pencil hardness test, a hard coat layer that is not damaged by two or more when a test is performed five times with a pencil hardness of 2H and a load of 500 gf is used.

  Surface treatment may be applied to the hard coat layer (2) opposite to the surface in contact with the transparent substrate (1). At this time, examples of the surface treatment method include corona discharge treatment, electron beam treatment, flame treatment, glow discharge treatment, and atmospheric pressure plasma treatment.

  In the present invention, it is particularly preferable to perform a low temperature plasma surface treatment. By performing the low temperature plasma treatment, the hydrophilicity is improved and the surface is moderately roughened, thereby improving the adhesion with a thin film to be subsequently laminated.

  Thereafter, the primer layer (3) may be provided on the hard coat layer (2). As a material of the primer layer (3), for example, a metal such as silicon, nickel, chromium, tin, gold, silver, platinum, zinc, titanium, tungsten, aluminum, zirconium, palladium, or two or more kinds of these metals. Or their oxides, fluorides, sulfides, nitrides, etc., which may be mixtures. Further, the primer layer (3) may have two or more layers.

  The primer layer (3) is used for improving adhesion. The thickness should just be a grade which does not impair the transparency of a transparent base material (1), Preferably, it is a physical film thickness and is about 1 nm or more and 10 nm or less. These primer layers are preferably formed by a dry coating method such as a sputtering method, a reactive sputtering method, a vapor deposition method, an ion plating method, or a chemical vapor deposition (CVD) method. In particular, a sputtering method is preferable. In the case where the primer layer and the antireflection layer are formed in the same vacuum apparatus, it is possible to form the film using a dual magnetron sputtering (DMS) method.

  The antireflection layer (4) comprising the optical thin film layer can be formed by a dry coating method such as a sputtering method, a reactive sputtering method, a vapor deposition method, an ion plating method, or a chemical vapor deposition (CVD) method. It is preferable to use a sputtering method that has high film thickness uniformity and few defects such as pinholes, and that is excellent in visibility, dense, and capable of forming a thin film with excellent mechanical properties such as scratch resistance. Among the sputtering methods, high productivity can be obtained due to a higher film formation rate and higher discharge stability. Therefore, a dual magnetron sputtering (hereinafter referred to as DMS) method in which film formation is performed by applying a voltage in the middle frequency range. Is the best.

  The sputtering method generally refers to a phenomenon in which atoms or ions are released to the outside when the atoms or ions collide with the surface of the solid (target). A thin film is formed by depositing. Various materials can be produced relatively easily, and are actively used industrially as a technique for circuit element configuration and the like. Sputtering techniques include magnetron sputtering and radio frequency (RF) sputtering.

As a selection of the DMS method, generally, film formation of SiOx, TiO ₂ or the like is performed by reactive sputtering from a conductive metal target. Therefore, it is necessary to select the best method as the film forming method. The DMS method solves this problem, and the structure of the DMS evaporation source.

  Specifically, the DMS evaporation source connects two sputter cathodes juxtaposed to both electrodes of an intermediate frequency AC power supply, and the two evaporation sources operate alternately as a negative electrode and a positive electrode. Since the surface of the target is always kept conductive by being sputtered while operating as a negative electrode, the function as an anode can be maintained for a long time, and discharge can be stably maintained. In addition, since the sputter roll coater processes a large area film, the continuous operation time of the evaporation source becomes long, and such stability is extremely important. In addition, technology that keeps the sputtering discharge mode in the so-called transition region by monitoring the sputtering voltage and the light emission from the generated plasma and controlling the flow rate of the reactive gas such as oxygen at high speed is also used to realize a high film deposition rate. And is the most suitable method for forming the antireflection layer of the present invention. In addition, as a vacuum pressure at the time of lamination | stacking, 0.1 Pa or more and 0.6 Pa or less were suitable.

  The antireflection layer (4) is composed of a single layer of a low refractive index transparent thin film having a refractive index of light at a wavelength of 550 nm of less than 1.6 and an extinction coefficient of light at a wavelength of 550 nm of 0.5 or less, A high refractive index transparent thin film layer having a light refractive index of 1.9 or more at a wavelength of 550 nm, a low refractive index transparent thin film layer having a light refractive index of less than 1.6, or a light refractive index of 1.6 or more but less than 1.9. Examples thereof include a plurality of layers in which optical thin films having different refractive indexes such as a medium refractive index transparent thin film layer are laminated. An antireflection layer comprising a plurality of layers is particularly preferred because of its extremely low reflectance and high antireflection performance. As the antireflection layer (4) composed of a plurality of layers, a high refractive index transparent thin film layer, a low refractive index transparent thin film layer, a high refractive index transparent thin film layer, and a low refractive index transparent thin film layer are laminated in order from the substrate side. The thing of the structure which was made is mentioned. If the thickness is 100 nm or less, an optical design that can obtain a sufficient antireflection function is not possible. In addition, although optical design can be performed at 300 nm or more, the thickness of the antireflection layer is preferably 100 nm or more and 300 nm or less considering that productivity is remarkably deteriorated.

  As the material for the high refractive index transparent thin film layer, indium, tin, titanium, silicon, zinc, zirconium, niobium, magnesium, bismuth, cerium, tantalum, aluminum, germanium, potassium, antimony, neodymium, lanthanum, thorium, hafnium, etc. Examples thereof include metals or alloys composed of two or more of these metals, oxides thereof, fluorides, sulfides, and nitrides. Specific examples include titanium oxide, niobium oxide, zirconium oxide, tantalum oxide, zinc oxide, indium oxide, and cerium oxide, but are not limited thereto. In addition, when a plurality of layers are stacked, it is not always necessary to select the same material, and the material may be appropriately selected according to the purpose. In particular, when sputtering is used, niobium oxide is suitable because of the small number of pinholes in the thin film produced.

  Examples of the material for the low refractive index transparent thin film layer include, but are not limited to, materials such as silicon oxide, titanium nitride, magnesium fluoride, barium fluoride, calcium fluoride, hafnium fluoride, and lanthanum fluoride. In addition, when a plurality of layers are stacked, it is not always necessary to select the same material, and it may be appropriately selected according to the purpose. In particular, silicon oxide is an optimal material in terms of optical characteristics, mechanical strength, cost, film formation appropriateness, and the like.

  By the way, the water vapor transmission amount of these antireflection films changes under the influence of the material and thickness of the base material and the functional layer, and further the temperature and humidity. The temperature dependence of moisture permeability is P = P0e-E / RT (where P: moisture permeability (unit thickness, water vapor transmission rate per unit water vapor pressure difference), P0: moisture permeability at absolute zero, E: (Activation energy of moisture permeability, R: gas constant, T: absolute temperature).

In the case of a TAC film widely used as a surface protective film for a polarizing plate, the water vapor transmission rate with a thickness of 100 μm is 380 g / m ² / day at a temperature of 40 ° C. and a relative humidity of 90%. On the other hand, in the case of a PET film, it is 6.5 g / m ² / day, which is much higher in water vapor barrier properties than TAC.

By laminating a film on this transparent substrate (1), it is possible for water vapor to be more difficult to permeate the film, but in particular, a film produced by sputtering forms a dense film, A film having high water vapor barrier performance is formed. Thus, the produced antireflection film can obtain high water vapor barrier performance. At this time, the water vapor transmission rate of the antireflection film is preferably 2.0 g / m ² / day or less. More preferably, it is 1.0 g / m ² / day or less.

  Moreover, it is preferable to provide an antifouling layer (5) on the outermost surface layer on the antireflection layer (4). The antifouling layer (5) is a layer obtained from a fluorine-containing silicon compound having two or more silicon atoms bonded to a reactive functional group.

  The reactive functional group in the present invention means a group capable of reacting with and bonding to the uppermost layer of the antireflection layer (4). Moreover, it is a layer formed by making the reactive functional groups of a fluorine-containing silicon compound react. Thereby, it is hard to get dirt on the surface, and even if it gets dirty, the wiping performance can be improved. Here, the film formation method of the antifouling layer is not particularly limited, but a film formation method by vacuum vapor deposition is suitable.

  According to this method, from the viewpoint of the work environment when forming the antifouling layer and the control of the film thickness of the antifouling layer, a diluting solvent is not required, and the film thickness of the antifouling layer, which has been difficult in the past, is angstrom order Therefore, it is possible to provide an antireflection film having a desired antifouling layer. Furthermore, it is possible to easily impart antifouling property without changing the interference color of the antireflection film, which does not affect haze, water vapor transmission rate, and color setting is difficult, because it can form a thin film, It is possible to form a film continuously with good film thickness uniformity.

  When the antifouling layer is formed by a dry coating method, the film thickness varies depending on the evaporation amount of the antifouling agent. Therefore, in order to accurately control the film thickness of the antifouling layer, it is preferable to accurately control the evaporation amount of the antifouling agent. In addition, after forming the antifouling layer on the substrate to be treated, heating, humidification, light irradiation, electron beam irradiation, or the like may be performed as necessary.

  At this time, in order to have sufficient antifouling performance, at least the water droplet contact angle needs to be 100 degrees or more. Thereby, sufficient water repellency and surface dirt wiping properties can be obtained. Further, since the friction coefficient is lowered, the scratch resistance can be further improved.

  In the antireflection film of the present invention, the haze is preferably 0.3% or less, the total light transmittance is 92% or more, and the luminous reflectance is 0.9% or less. When the haze, the total light transmittance, and the luminous reflectance are within the above ranges, a functional PET film having extremely high transparency and low reflection can be realized.

  EXAMPLES Hereinafter, although an Example and a comparative example further demonstrate this invention, this invention is not limited to the following Example.

As shown in FIG. 1, a 100 μm thick PET film is applied to the transparent substrate film (1), an ultraviolet curable acrylic resin is applied, dried and UV cured, and a hard coat layer (2) having an arbitrary thickness. Was provided. Glow plasma treatment is performed, and as a primer layer (3), an SiO layer is formed with a film thickness of 3 nm by a sputtering method, and then an antireflection layer (4) is formed under an arbitrary film formation pressure condition by a sputtering method. Then, the layers were formed from Nb ₂ O ₅ / SiO ₂ / Nb ₂ O ₅ / SiO ₂ from the hard coat side, and the film thickness of each layer was 15 nm / 25 nm / 105 nm / 85 nm, respectively.

Example 1
Using a PET film with a haze of 0.34% and a total light transmittance of 93.4% as the transparent substrate, the hard coat layer has a thickness of 3 μm, a pencil hardness of 2H, 5/5 at 500 gf load, and antireflection The antireflection layer was formed at a layer pressure of 0.3 Pa.

(Example 2)
Using a PET film having a haze of 0.27% and a total light transmittance of 90.4% as the transparent substrate, the hard coat layer has a thickness of 2 μm, a pencil hardness of 2H, 4/5 at 500 gf load, and antireflection The antireflection layer was formed at a pressure of 0.5 Pa.

(Comparative Example 1)
Using a PET film having a haze of 1.0% and a total light transmittance of 89% as the transparent substrate, the hard coat layer has a thickness of 5 μm, a pencil hardness of 2H, 5/5 at a load of 500 gf, and an antireflection layer. The antireflection layer was formed under a film forming pressure condition of 0.8 Pa.

(Comparative Example 2)
Using a PET film having a haze of 0.34% and a total light transmittance of 93.4% as the transparent substrate, the hard coat layer has a thickness of 6 μm, a pencil hardness of 2H, 5/5 at 500 gf load, and antireflection The antireflection layer was formed at a pressure of 1.0 Pa.

  Thereafter, a fluorine-containing silicon compound was added in an amount of 20 wt% with perfluorohexane on the outermost surface of the antireflection layer formed in (Example 1) to (Example 2) and (Comparative Example 1) to (Comparative Example 2). The antifouling layer (5) was formed by vacuum evaporation using a diluted antifouling agent.

In the evaluation, a resistance heating method of a vacuum evaporation method was used. When performing the resistance heating method, an antifouling agent having a solid amount of 5 mg was accommodated in a boat and evacuated to 5 × 10 ⁻⁵ torr or less. Thereafter, the boat was heated to 400 ° C. to evaporate the antifouling agent and form an antifouling layer.

  Moreover, the sample obtained by the Example and the comparative example was evaluated with the following method. The results are shown in (Table 1).

(Optical property evaluation)
(A) Reflectance measurement The reflectance (luminous reflectance) was measured using a spectrophotometer (U-4000 manufactured by Hitachi, Ltd.). In addition, in order to cut off the reflection from the back surface, the back surface side of the sample was treated with a matte black paint spray. In the measurement, a regular reflection 5 ° unit was used.

(B) Haze and total light transmittance measurement The haze meter (NDH2000 by Nippon Denshoku Industries Co., Ltd.) was used for the measurement. At this time, incident light was incident from the antifouling layer (antireflection layer) side. In addition, about haze measurement, it measured based on JIS-K7105.

(Mechanical property evaluation)
(C) Scratch resistance test Steel wool (Bonster # 0000 made by Nippon Steel Wool) with a load of 500 or 1000 gf applied to the antiglare film using a Gakushin type friction fastness tester (AB-301 manufactured by Tester Sangyo Co., Ltd.) ) Was rubbed back and forth for 10 times on the antireflection layer of each sample, and the wear state (number of scratches) of the sample was visually observed. Judgment criteria are shown below.
◎: No scratch ○: Less than 10 scratches ×: 10 or more scratches

(D) Pencil hardness test Based on JIS-K5400, a load of 500 gf was applied to a pencil with a pencil hardness of 2H, and the film was traced five times to visually observe the abrasion state (number of scratches) of the sample. If the line is drawn 5 times and there is no scratch, it is expressed as 5/5, and if there are 5 scratches, it is expressed as 0/5. Judgment criteria are shown below.
A: 5/5, 4/5
○: 3/5
Δ: 2/5
X: 1/5, 0/5

(E) Water vapor transmission rate In the antireflection film (100), the water vapor transmission rate in an environment of a temperature of 40 ° C and a relative humidity of 90% Rh was measured. In addition, the water vapor transmission rate was measured using a method according to JIS-Z0208.

(F) Bending test A round bar having a diameter of 12 mm is wound with the antireflection layer surface facing outward without applying a load to the sample. After removing the sample from the bar, visually check for cracks. Repeat 5 times per sample.
◎: No cracks occurred 5 times out of 5 times ○: No cracks occurred 3-4 times out of 5 times △: Cracks occurred 3 times or more out of 5 times, but the number of cracks is within 10 ×: 5 Unlimited number of 5 cracks

(G) Contact angle measurement Using a contact angle meter (CA-X type, manufactured by Kyowa Interface Science Co., Ltd.), a droplet having a diameter of 1.8 mm is formed on the needle tip in a dry state (20 ° C.-65% RH). Droplets were made in contact with the surface of the sample (solid). The contact angle is an angle formed by a tangent to the liquid surface at a point where the solid and the liquid are in contact with the solid surface, and is defined as an angle on the side including the liquid. As the liquid, distilled water and n-hexadecane were used, respectively.

(H) Adhesiveness of oil-based pen Using an oil-based pen (Magic ink, No. 500 for fine writing), a straight line having a length of 1 cm was written on the surface of the sample, and this was determined by visual judgment of the ease of sticking or conspicuousness. . The judgment criteria were as follows.
○: The handwriting with the oil pen is repelled in a spherical shape ×: The handwriting with the oil pen is not repelled, and a straight line is drawn

(I) Wipeability of oil-based pen The oil-based pen adhering to the sample surface was wiped off with a cellulose nonwoven fabric (Pencot M-3 manufactured by Asahi Kasei Co., Ltd.), and the ease of removal was visually determined. The judgment criteria were as follows.
○: The oil pen can be completely wiped off. Δ: The oil pen remains after being wiped. ×: The oil pen cannot be wiped off.

(J) Adhesiveness of fingerprints A finger was pressed against the sample surface for several seconds to attach the fingerprints, and this was determined by visual judgment of the ease of attaching or conspicuous. The judgment criteria were as follows.
○: There is little adhesion of fingerprints, and attached fingerprints are not conspicuous ×: Attachment of fingerprints can be confirmed

(K) Fingerprint wiping property The fingerprint adhering to the sample surface was wiped off with a cellulose nonwoven fabric (Pencot M-3 manufactured by Asahi Kasei Co., Ltd.), and the ease of removal was visually determined. The judgment criteria were as follows.
○: Fingerprints can be completely wiped △: Fingerprint wipe marks remain ×: Fingerprints cannot be wiped off

  Also for the antireflection films prepared in (Comparative Example 1) to (Comparative Example 2), it is possible to achieve a precise optical design and obtain sufficient antireflection performance because of the film formation by the sputtering method. However, it can be seen that each evaluation item is inferior.

  On the other hand, when the antireflection film prepared in (Example 1) and (Example 2) is used, good results can be obtained in all properties such as optical properties, mechanical properties, bending properties, water vapor barrier properties. It was. Thereby, it can confirm that it has the outstanding antireflection function, the outstanding mechanical property, the outstanding environmental durability, the outstanding water vapor | steam barrier property, and the outstanding processing characteristic.

  According to the antireflection film developed in the present invention, not only the antireflection function, but also excellent mechanical properties, environmental durability, and post-processing characteristics, for example, the surface of a portable game machine, a mobile phone, a wristwatch, a portable game machine, When added to devices and objects that are frequently used in daily life, such as cameras and eyeglass lenses, it adds additional value and expands its applicability.

DESCRIPTION OF SYMBOLS 1 Transparent base material 2 Hard-coat layer 3 Primer layer 4 Antireflection layer 5 Antifouling layer 100 Antireflection film

Claims (6)

On at least one surface of the transparent substrate, a hard coat layer and an antireflection layer are sequentially laminated, and the antireflection layer comprises four or more layers in which a high refractive material layer and a low refractive index layer are alternately laminated. In the laminate, the antireflection film in which the outermost thin film of the antireflection layer is a low refractive index layer,
(A) The thickness of the transparent substrate is 70 μm or more and 200 μm or less, the haze is 0.5% or less, and the total light transmittance is 88% or more,
(B) The thickness of the hard coat layer is 1.5 μm or more and 6 μm or less,
(C) The total thickness of the antireflection layer is 100 nm or more and 300 nm or less,
(D) The haze of the antireflection film is 0.3% or less, the total light transmittance is 92% or more, the luminous reflectance is 0.9% or less, and the water vapor transmission rate is 2.0 g / m ² / An antireflection film characterized by being not more than day.   The antireflection film according to claim 1, wherein the transparent substrate is a polyethylene terephthalate film.   3. The antireflection film according to claim 1, wherein the low refractive index layer of the antireflection layer is silicon oxide and the high refractive index layer is niobium oxide.   Between the hard coat layer and the antireflection layer, a primer layer made of a metal, an alloy made of two or more metals, a metal compound, or a mixture thereof is provided. The antireflection film according to any one of claims 1 to 3, wherein   The antireflection film according to any one of claims 1 to 4, wherein an antifouling layer containing a fluorine compound is provided on the surface of the antireflection layer. On at least one surface of the transparent substrate, a hard coat layer and an antireflection layer are sequentially laminated, and the antireflection layer comprises four or more layers in which high refractive material layers and low refractive index layers are alternately laminated. In the laminate, in the method for producing an antireflection film in which the outermost thin film of the antireflection layer is a low refractive index layer,
Laminating the antireflection layer by sputtering;
Laminating the antifouling layer by vacuum deposition;
The manufacturing method of the antireflection film characterized by comprising.

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