JP6186850B2 - Optical functional film manufacturing method and optical functional film coating apparatus - Google Patents

Description

  The present invention relates to a method for producing an optical functional film, and an optical functional film coating apparatus.

Currently, many multilayer optical functional films in which a plurality of optical functional layers are laminated on a transparent substrate have been proposed.
Examples of such a multilayer optical functional film include an antireflection film in which a high refractive index layer and a low refractive index layer are laminated in this order on a transparent substrate, and reflection is prevented by an optical interference function. (Patent Document 1).

  Such a multilayer optical functional film is usually wound up and inspected for physical properties every time each layer is formed. After all the optical functional layers are formed, a final physical property inspection is performed as to whether or not the quality standards are met. For example, the completed optical functional film is inspected for total light transmittance, haze, reflectance, and the like.

JP 2012-150226 A

However, in such a multilayer optical functional film, the final physical properties may deviate from the appropriate values. This is probably because the result of the coating test performed in advance is not reflected as it is.
That is, in the case of a thin-film multilayer laminate, the composition is adjusted in order to obtain the desired film thickness, refractive index, etc. for each layer, and a pre-coating test is performed to determine whether the film meets the purpose. And it coats on the base material of a real product on the conditions that this test is good. Since the test is generally performed on a single wafer, coating, drying, curing, and the like are performed intermittently in each process and between processes. Also, for each process condition, for example, tension, It is impossible to make it exactly the same as continuous production conditions such as wind direction, heat transfer, ultraviolet intensity distribution, etc., and the actual film quality may deviate from quality standards due to this difference. Moreover, when another thin film is formed on a thin film, the solvent and monomer of the coating liquid which form an upper thin film may permeate | transmit a lower thin film, and film quality may remove | deviate from quality standards. And as a result of the film quality of each layer deviating from the quality standard, it is considered that the physical properties of the entire optical functional film deviate from the appropriate values.

In order to solve the above problem, a means for performing a final inspection process (inline, off-line) and reflecting the result of the final inspection in the manufacturing process can be considered.
However, as described above, since the multi-layered optical functional film employs a method of being wound up every time each layer is formed, for example, even if the final inspection process is inlined to improve efficiency, The inspection result can be reflected only on the last layer to be formed. The physical properties of the multilayer optical functional film are such that each layer interacts, and the allowable refractive index and film thickness are narrow for each layer. There are cases where it is not possible.
In addition, even if the inspection at the stage of forming each layer is made inline, unexpected physical properties may be obtained after the last layer is formed. In that case, the physical property value is corrected only with the last layer. Difficult to do.
If the final physical properties cannot be satisfied by the final inspection, the manufactured optical functional film, the in-process laminated film before coating the last layer, and the coating solution in use will be discarded, resulting in a significant increase in yield. It will decline. In addition, everything is redone from the production stage of the coating liquid, and the production efficiency is greatly reduced.

  The present invention has been made under such circumstances, and an object thereof is to provide a method for producing an optical functional film having a good yield and excellent production efficiency, and an optical functional film coating apparatus. .

The method for producing an optical functional film of the present invention that solves the above-mentioned problems is to control a coating film forming means for continuously forming two or more optical functional layers in-line and a coating film forming means for at least one optical functional layer. The following steps 1 to 4 are sequentially performed using an optical functional film coating device having a coating film forming condition control means.
Step 1: Step of continuously forming two or more optical functional layers on a transparent substrate Step 2: Inspection means A for inspecting physical properties of an optical functional film located inline and / or off-line of a coating apparatus Step 3: Inspecting the physical properties of the optical functional film Step 3: Comparing the appropriate range of the physical properties of the optical functional film with the inspection result of Step 2 Step 4: The inspection result is out of the appropriate range in Step 3 When the coating film forming condition control means of the coating device, the step of forming the optical functional layer by controlling at least one coating film forming condition, Also, the coating device of the optical functional film of the present invention,
At least one coating film forming means for continuously forming two or more optical functional layers in-line, and inspection means A for inspecting the physical properties of the optical functional film located in-line after the last coating film forming means Coating film forming condition control means for controlling the coating film forming means of the two optical functional layers, a database storing the appropriate range of physical properties of the optical functional film, and the result of comparing the inspection result and the appropriate range. And means for reflecting the film forming condition control means.

  The method for producing an optical functional film of the present invention has a good yield and excellent production efficiency. In addition, the optical functional film coating apparatus of the present invention can produce an optical functional film having a good yield and excellent production efficiency.

Schematic which shows one Example of the coating apparatus of the optical functional film of this invention The flowchart which shows one Example of the manufacturing method of the optical functional film of this invention

[Method for producing optical functional film]
The method for producing an optical functional film of the present invention comprises: a coating film forming means for continuously forming two or more optical functional layers in-line; and a coating film forming condition for controlling the coating film forming means for at least one optical functional layer. Using the optical functional film coating apparatus having a control means, the following steps 1 to 4 are sequentially performed.
Step 1: Step of continuously forming two or more optical functional layers on a transparent substrate Step 2: Inspection means A for inspecting physical properties of an optical functional film located inline and / or off-line of a coating apparatus Step 3: Inspecting the physical properties of the optical functional film Step 3: Comparing the appropriate range of the physical properties of the optical functional film with the inspection result of Step 2 Step 4: The inspection result is out of the appropriate range in Step 3 A step of forming an optical functional layer by controlling at least one coating film forming condition by the coating film forming condition control means of the coating apparatus.

  FIG. 1 is a schematic view showing one embodiment of the optical functional film coating apparatus of the present invention, and FIG. 2 is a flowchart showing one embodiment of the method for producing the optical functional film of the present invention. . Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 and 2 as appropriate.

<Step 1>
In step 1, an optical functional layer is continuously formed inline on a transparent substrate by a coating apparatus having two or more coating film forming means. The coating apparatus of FIG. 1 has three coating film forming means and can continuously form three optical functional layers in-line. In FIG. 1, the transparent base material is sent out to the line of the coating apparatus 1 by the unwinder 15. Further, after the formation of all the optical functional layers and the inspection by the inspection means A described later are completed, the optical functional film is wound up by the winder 16.
Note that “continuous” in the present invention is not limited to the same surface side, but includes continuity including both surfaces. For example, what forms an optical functional layer in one surface of a transparent base material and forms an optical functional layer in the surface of the other side before winding up shall also be included in the "continuous" of this invention.
However, “continuous” in the present invention is not limited to continuously forming all the optical functional layers. For example, a plurality of optical functional layers are continuously formed on one surface of the transparent substrate and wound up, and then a plurality of optical functional layers are continuously formed on the opposite surface. It shall be included continuously. In addition, it is preferable to form all the optical functional layers on the same surface side of the transparent substrate continuously. This is because by continuously forming all the optical functional layers on the same surface side, there are more control options in step 4 to be described later, and the effects of the present invention are easily exhibited.
In the present invention, since the optical functional layer is continuously formed in-line in step 1, yield and production efficiency can be improved by a synergistic effect with the steps described later. In addition, in the case of a method of winding each layer as in the conventional manufacturing method, a defect occurs on the core side due to the pressure during winding, and when the roll is sent out when forming the second and subsequent layers There are many factors that reduce the yield due to the generation of static electricity and the adhering of dust. In the present invention, since the number of windings and the number of feedings can be minimized, a decrease in yield can be reduced.

As a transparent base material, it is preferable that it is provided with light transmittance, smoothness, and heat resistance, and was excellent in mechanical strength. Such transparent substrates include polyester, triacetyl cellulose (TAC), cellulose diacetate, cellulose acetate butyrate, polyamide, polyimide, polyether sulfone, polysulfone, polypropylene, polymethylpentene, polyvinyl chloride, polyvinyl acetal. , Polyether ketone, polymethyl methacrylate, polycarbonate, polyurethane, and amorphous olefin (Cyclo-Olefin-Polymer: COP). The transparent substrate may be a laminate of two or more plastic films. Among the plastic films, when the retardation value is 3000 to 30000 nm or when the image of the liquid crystal display is observed through polarized sunglasses, unevenness of different colors is observed on the display screen. This is preferable in that it can be prevented.
Among these plastic films, polyester (polyethylene terephthalate, polyethylene naphthalate) that has been stretched, especially biaxially stretched, is less susceptible to the effects of solvents, monomers, etc. contained in the coating liquid that forms the optical functional layer. It is preferable in that it is easy to adjust and excellent in mechanical strength and dimensional stability.

The thickness of the transparent substrate is preferably 5 to 300 μm, and more preferably 10 to 200 μm.
In order to improve adhesion, the surface of the transparent substrate may be preliminarily coated with a coating called an anchor agent or a primer in addition to physical treatment such as corona discharge treatment and oxidation treatment.

Examples of the coating film forming means for the optical functional layer include known coating means such as dip coating, roll coating, bar coating, die coating, gravure coating, blade coating, and air knife coating. The coating film forming means for each optical functional layer may be the same or different.
In addition, when the optical function layer coating liquid contains a solvent, it is preferable to have a drying means after the coating film forming means. Moreover, when the optical functional layer coating solution contains an ionizing radiation curable resin composition, it is preferable to have ionizing radiation irradiation means after the coating film forming means.
In the present invention, at least one coating film forming means includes a coating film forming condition control means. In FIG. 1, all three coating film forming means have a coating film forming condition control means. The coating film forming unit and the coating film forming condition control unit are associated with each other. Details of the coating film formation condition control means will be described later.

  The solvent of the coating solution for the optical functional layer is not particularly limited. For example, alcohols such as methanol, ethanol and isopropyl alcohol (IPA); ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; esters such as ethyl acetate and butyl acetate And halogenated hydrocarbons; aromatic hydrocarbons such as toluene and xylene; glycol ethers such as propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate and dipropylene glycol monomethyl ether, or mixtures thereof.

The optical functional layer may be provided on the same surface of the transparent substrate as in (i) and (ii) below, or may be provided on both surfaces as in (iii). In the case of the types (i) and (ii), the same optical functional layer may be provided on the opposite surface of the transparent substrate.
(I) Transparent substrate / light functional layer a / light functional layer b
(Ii) Transparent substrate / light functional layer a / light functional layer b / light functional layer c
(Iii) optical functional layer c / transparent substrate / optical functional layer a / optical functional layer b
Examples of the function that the optical functional layer produces include hard coating, antistatic, antiglare, antifouling, antireflection, invisible wiring pattern, blocking, and Newton ring. These functions may be functions that occur in association with each other between the plurality of optical functional layers.
In the present invention, as the optical functional layer, a plurality of transparent layers having different refractive indexes of layers in contact with each other, and a transparent layer that causes optical interference between the plurality of transparent layers (hereinafter referred to as “a plurality of transparent layers”) It is preferable to include.
Examples of the function caused by optical interference of the plurality of transparent layers include antireflection, invisibility of a wiring pattern made of a transparent conductive film, and the like. Since the functions of these plural transparent layers are exhibited by optical interference between the plural transparent layers, and the width of the film thickness and refractive index allowed for each layer are narrow, the production method of the present invention is extremely useful.

Examples of the plurality of transparent layers include a high refractive index layer having a thickness of 200 nm or less and a refractive index of 1.50 to 2.00, and a low refractive index layer having a thickness of 200 nm or less and a refractive index of 1.20 to 1.50. It is done.
Moreover, about the structural member of a touch panel, and the optical member installed on a touch panel, exact | strict optical characteristics are requested | required by the request | requirement, such as invisibility of a wiring pattern. For this reason, when using the optical functional film manufactured by this invention for the structural member of a touch panel, or the structural member of the optical member installed on a touch panel, the thickness and refractive index of a some transparent layer are stricter. Control is required. Specifically, the high refractive index layer preferably has a thickness of 10 to 100 nm and a refractive index of 1.60 to 1.70, and the low refractive index layer has a thickness of 10 to 100 nm and a refractive index of 1.40. It is preferably 1.49. The thickness of the high refractive index layer and the low refractive index layer is more preferably 30 to 70 nm.
Note that an intermediate refractive index layer having a thickness of 200 nm or less and a refractive index of 1.50 to 1.70 may be provided between the high refractive index layer and the low refractive index layer. When using the optical functional film for a touch panel as described above, the middle refractive index layer preferably has a thickness of 10 to 100 nm, a refractive index of 1.55 to 1.65, and a thickness of 30 to 70 nm. Is more preferable.

The high refractive index layer or medium refractive index layer contains, for example, a binder resin and refractive index adjusting particles.
As the refractive index adjusting particles, particles having a desired refractive index may be selected. The particles having a relatively high refractive index include zinc oxide (1.90), titanium oxide (2.3 to 2.7), cerium oxide (1.95), and tin-doped indium oxide (1.95 to 2.00). Antimony-doped tin oxide (1.75 to 1.85), yttrium oxide (1.87), zirconium oxide (2.10), and the like. In addition, the inside of the said parenthesis shows the refractive index of the material of each particle. The average particle diameter of these particles is usually 100 nm or less.

The binder resin is not particularly limited, and a thermoplastic resin can be used. From the viewpoint of increasing the surface hardness, a curable resin composition such as a thermosetting resin composition or an ionizing radiation curable resin composition. What is formed from is preferable, and what is formed from an ionizing radiation curable resin composition is especially preferable.
The thermosetting resin composition includes a curable resin such as an acrylic resin, urethane resin, phenol resin, urea melamine resin, epoxy resin, unsaturated polyester resin, silicone resin, and a curing agent added as necessary. Or a monomer comprising the curable resin and a curing agent.

Examples of the ionizing radiation curable resin composition include compounds having one or more unsaturated bonds such as a compound having an acrylate or methacrylate functional group.
Examples of the compound having one unsaturated bond include ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone and the like.
Examples of the compound having two or more unsaturated bonds include polymethylolpropane tri (meth) acrylate, hexanediol (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri ( (Meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate Polyfunctional compounds such as these, compounds obtained by modifying these compounds with ethylene oxide, polyethylene oxide, etc., and these polyfunctional compounds and (meth) acrylates Response product (e.g., a polyhydric alcohol (meth) acrylate ester oligomer), it may be mentioned those polyfunctional compounds and reaction products of isocyanate compounds (urethane (meth) acrylate oligomer), or the like. In the present specification, “(meth) acrylate” refers to methacrylate and acrylate.

In addition, these compounds may have a refractive index adjusted to be high by introducing an aromatic ring, a halogen atom other than fluorine, sulfur, nitrogen, phosphorus atoms, or the like.
In addition to the above compounds, relatively low molecular weight polyester resins having unsaturated double bonds, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, etc. Can also be used as an ionizing radiation curable resin composition.

When the ionizing radiation curable resin composition is cured by ultraviolet irradiation, it is preferable that the composition contains an additive such as a photopolymerization initiator or a photopolymerization accelerator.
Examples of the photopolymerization initiator include acetophenone, benzophenone, Michler ketone, benzoin, benzyl methyl ketal, benzoyl benzoate, α-acyl oxime ester, α-hydroxy ketone, and thioxanthone. In the present invention, from the viewpoint of increasing the hardness of the high refractive index layer and the low refractive index layer, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methylpropionyl) benzyl] phenyl} -2- Methylpropan-1-one is preferred.
Further, the photopolymerization accelerator can reduce the polymerization obstacle due to air at the time of curing and increase the curing speed. For example, p-dimethylaminobenzoic acid isoamyl ester, p-dimethylaminobenzoic acid ethyl ester, and the like. can give.

Examples of the low refractive index layer include those comprising a binder component and refractive index adjusting particles, and those comprising a single material having a low refractive index.
As the binder component, the binder resin exemplified in the high refractive index layer to the medium refractive index layer can be used. Further, a resin having a low refractive index such as a resin into which fluorine atoms are introduced or organopolysiloxane may be mixed as a binder component.
Examples of the refractive index adjusting particles used for the low refractive index layer include silica, magnesium fluoride, and hollow particles thereof. The average particle diameter of these particles is usually 100 nm or less.
In the case where the low refractive index layer is formed from a single material having a low refractive index, a material having a low refractive index such as a resin into which fluorine atoms are introduced or organopolysiloxane can be used.

  The low refractive index layer contains a binder component and refractive index adjusting particles, and the refractive index adjusting particles are localized on the side far from the transparent substrate side in the depth direction of the low refractive index layer. It may be a thing. In the low refractive index layer having such a configuration, since the ratio of the binder component on the transparent substrate side is increased, the monomer component of the binder component penetrates into the lower layer, and the physical properties of the lower layer and its own layer are determined from the appropriate values. It becomes easy to come off. In this invention, even if it uses the low refractive index layer which is easy to produce such a physical-property change, the physical property as the whole optical functional film can be made into an appropriate value.

In order to form a low refractive index layer in which the refractive index adjusting particles are localized as described above, it is preferable to use reactive silica particles having a reactive functional group on the silica surface as the refractive index adjusting particles.
As the reactive functional group, a polymerizable unsaturated group is suitably used, preferably a photocurable unsaturated group, and particularly preferably an ionizing radiation curable unsaturated group. Specific examples thereof include (meth) acryloyl groups, (meth) acryloyloxy groups, ethylenically unsaturated bonds such as vinyl groups and allyl groups, and epoxy groups.
Examples of such reactive silica particles include silica particles surface-treated with a silane coupling agent. To treat the surface of the silica particles with a silane coupling agent, a dry method in which the silane coupling agent is sprayed on the silica particles, a wet method in which the silica particles are dispersed in a solvent, and then the silane coupling agent is added to react. Is mentioned.

In order to form a low refractive index layer in which the refractive index adjusting particles are localized as described above, pentaerythritol tri (meth) acrylate, diacrylated isocyanurate, stearic acid modified pentane is used as an ionizing radiation curable resin composition. It is preferable to use one containing polyfunctional (meth) acrylate having at least one OH group as a constituent such as erythritol diacrylate, triglycerol diacrylate, epichlorohydrin-modified glycerol triacrylate. Note that including as a constituent element means that the polyfunctional (meth) acrylate reacts with another material (for example, an isocyanate compound) in the ionizing radiation curable resin composition, so that at least one OH group is present. It is meant to include those that exist in the form of remaining.
When these polyfunctional (meth) acrylates having one or more OH groups are used in combination with reactive silica particles, the silica particles can be easily localized on the side far from the transparent substrate, and the adhesion, It is easy to improve film properties and slipperiness. In addition, by using a polyfunctional (meth) acrylate having one or more OH groups and reactive silica particles in combination, the ratio of the binder resin on the transparent substrate side of the low refractive index layer can be increased, resulting in low refraction. After the transparent conductive film is formed, it is easy to improve the adhesion between the refractive index layer and the underlying layer or transparent substrate, and it is difficult for the etching solution or cleaning solution to enter from the transparent substrate side of the low refractive index layer. The etching resistance can be easily improved. These effects are more suitable when a polyfunctional acrylate having one or more OH groups is included as a constituent in the ionizing radiation curable resin composition, and more preferable when pentaerythritol triacrylate (PETA) is included as a constituent. It is.

  Moreover, it is preferable to have a hard-coat layer between a transparent base material and a some transparent layer from a viewpoint of improving abrasion resistance. Since the plurality of transparent layers are thin films, there is a limit to improving the scratch resistance even if the layers are formed with an ionizing radiation curable resin composition, but a hard coat layer having no thickness limitation is provided. Thus, the scratch resistance can be made more sufficient. The hard coat layer is preferably formed from the hard coat layer forming composition including the curable resin composition exemplified as the binder resin of the high refractive index layer and the fine particles contained as necessary. Of the curable resin compositions, ionizing radiation curable resin compositions are preferred.

  The pencil hardness of JIS K5600-5-4 (1999) on the surface of the hard coat layer is preferably F or more. By setting the pencil hardness to F or higher, the hardness of the hard coat layer can be sufficiently reflected on the surfaces of the plurality of transparent layers, and the durability can be improved. In addition, from the viewpoint of adhesion to a layer formed on the hard coat layer, toughness, and curl prevention, the upper limit of the pencil hardness on the surface of the hard coat layer is preferably about 2H. Since the touch panel is repeatedly pressed and requires high adhesiveness and toughness, the upper limit of the pencil hardness of the hard coat layer is set to 2H, so that the optical functional film is installed on the touch panel components or the touch panel. When used as a constituent member of an optical member, a remarkable effect can be exhibited. In addition, when using an optical functional film as a structural member of a touch panel or an optical member installed on a touch panel, it is preferable to use an optical functional film in locations other than the outermost surface of these structural members.

  The thickness of the hard coat layer is preferably 10 μm or less, and more preferably 1 to 5 μm. By setting the thickness to 2 μm or more, the hard coat layer surface can be made sufficiently hard, and by setting the thickness to 5 μm or less, the occurrence of curling can be prevented.

  From the viewpoint of preventing interference fringes, the refractive index of the hard coat layer is preferably 0.03 or less from the transparent substrate. However, even if the refractive index of the hard coat layer does not satisfy the above conditions, TAC is used as the transparent base material, the solvent of the hard coat layer forming composition is infiltrated into the TAC, and the interface disappears. Interference fringes can also be reduced by forming a primer layer having an intermediate refractive index between the transparent substrate and the hard coat layer between the hard coat layer.

In the present invention, it is preferable that the optical functional layer formed first does not contain particles protruding from the surface of the optical functional layer located on the outermost surface. In the case of the conventional manufacturing method which winds up each time one optical functional layer is formed, the optical functional layer formed first contains large particles that protrude from the surface of the optical functional layer, and is formed later. Prevents a series of blocking, including during winding. On the other hand, in the present invention, since the optical functional layer is formed continuously, it is only necessary to consider the winding after the last optical functional layer is formed, and the addition of particles protruding from the surface of the optical functional layer is sufficient. Is no longer necessary. In addition, since the particles protruding from the surface of the optical functional layer may adversely affect the formation of the transparent conductive film on the surface of the optical functional film, the occurrence of the adverse effects can be prevented by not using the particles. can do.
As particles protruding from the surface of the optical functional layer, non-aggregated particles having an average particle diameter of 500 nm or more are mainly used. In the present invention, when such large particles are included in the optical functional layer that is initially formed, although there is an effect in preventing blocking, it tends to cause defects in a large number of subsequent processes to be further laminated. It is preferable not to use it.

Further, in the present invention, it has three or more functional layers on the same surface on the transparent substrate, and any one or more of the optical functional layers other than the optical functional layer to be formed first has the following conditions: 1 is preferably contained.
Condition 1: [Average particle diameter of aggregated particles / film thickness of layer containing aggregated particles + film thickness of layer formed on the opposite side of the transparent substrate of the layer] = 0.8 to 5.0
For example, when having a hard coat layer, a high refractive index layer, and a low refractive index layer in this order on a transparent substrate and containing aggregated particles in the high refractive index layer, [average particle diameter of aggregated particles / high refractive index The ratio of the film thickness of the refractive index layer + the film thickness of the low refractive index layer] is preferably 0.8 to 5.0.
By adopting this configuration, irregularities are formed on the surface of the optical functional layer, and blocking can be prevented without including large particles that protrude from the surface of the optical functional layer in the first layer or the like. . The value of Condition 1 is more preferably 1.0 to 4.0, and further preferably 1.5 to 3.0.

Moreover, when it has a hard-coat layer, a high-refractive-index layer, and a low-refractive-index layer in this order on a transparent base material and contains aggregated particles in the high-refractive-index layer, the following conditions 2 and 3 are further satisfied Is preferred.
Condition 2: [Average particle diameter of aggregated particles / film thickness of high refractive index layer] = 1.0 to 10.0
Condition 3: [Average particle diameter of aggregated particles / film thickness of low refractive index layer] = 1.0 to 10.0
The values of conditions 2 and 3 are more preferably 2.0 to 8.0, and more preferably 3.0 to 6.0.

  The particles that are the basis of the above-mentioned aggregated particles are not particularly limited, inorganic particles such as calcium carbonate, magnesium carbonate, barium sulfate, aluminum hydroxide, silica, kaolin, clay, talc, acrylic resin particles, polystyrene resin particles, Resin particles such as polyurethane resin particles, polyethylene resin particles, benzoguanamine resin particles, and epoxy resin particles can be used. As such fine particles, spherical fine particles are preferably used from the viewpoint of handleability and ease of control of the surface shape, and resin particles are preferably used from the viewpoint of not hindering transparency. Further, from the viewpoint of preventing blocking, particles that tend to collect on the surface or tend to float in the film to which fine particles are added are preferable, and it is also preferable to use silica fine particles in which the phenomenon is noticeable.

The average particle diameter of the aggregated particles itself is preferably 70 to 300 nm, and more preferably 100 to 200 nm. Moreover, it is preferable that the average primary particle diameter of the inorganic fine particles constituting the aggregated particles is 5 to 50 nm.
The average diameter of the agglomerated particles is 2 to 3 randomly extracted agglomerated particles in a TEM image of a cross section of the optical functional film taken with a transmission electron microscope at an acceleration voltage of 30 kV, an emission current value of 10 μA, and a magnification of 200 K. Then, after measuring each particle size, imaging of another screen of the same sample was performed 5 times or more, and similarly, 2-3 aggregated particles were randomly extracted, and each particle size was measured. The number average value of the aggregated particles is taken as the average particle diameter (nm). The particle diameter of each aggregated particle is an average value of the major axis and the minor axis in the cross section of the aggregated particle. The major axis is the longest diameter in the cross section of the aggregated particles. The minor axis is a distance between two points where a line segment perpendicular to the midpoint of the line segment constituting the major axis is drawn and the perpendicular line segment intersects with the aggregated particles.
The content of the aggregated particles is preferably 0.1 to 5% by mass in the optical functional layer containing the particles, and more preferably 0.1 to 3% by mass.

At least one surface of the optical functional film has an arithmetic average roughness Ra (JIS B0601: 2001) of preferably 1.0 to 6.0 nm, and more preferably 1.3 to 4.0 nm. More preferably, the thickness is 1.5 to 2.8 nm. When Ra is 6.0 nm or less, a decrease in transparency can be prevented. Further, by setting Ra to 1.0 nm or more, it is possible to improve the slipperiness and easily prevent blocking.
Further, from the viewpoint of balance between transparency and slipperiness, at least one surface of the optical functional film preferably has a kurtosis Rku (JIS B0601: 2001) of a roughness curve of 3.0 or less. More preferably, it is 5 or more and 2.9 or less.

Examples of the overall layer structure of the optical functional film of the present invention include the following structures.
(I) Low refractive index layer / High refractive index layer / Hard coat layer / Transparent substrate / Hard coat layer / High refractive index layer / Low refractive index layer (ii) Hard coat layer / Transparent substrate / Hard coat layer / High Refractive index layer / low refractive index layer (iii) transparent substrate / hard coat layer / high refractive index layer / low refractive index layer In addition, as in the configuration of (ii), the optical functional layer on one side of the transparent substrate When is a single layer, the layer may contain the above-described particles or aggregated particles protruding from the surface of the optical functional layer.
Although the optical functional film which consists of such a structure can be used without being restrict | limited especially, it can be used conveniently as a structural member of a touch panel, or an optical member installed on a touch panel.

  Examples of the optical functional layer include the configurations described above. In addition, when the main binder resin and / or the main solvent forming the adjacent optical functional layer are the same, the binder component or the solvent penetrates into the lower layer, and the physical properties of the lower layer and the own layer easily deviate from the appropriate values. Even in such a case, the present invention is preferable in that the physical property can be adjusted to an appropriate value by controlling the coating film forming condition control means.

<Process 2>
In step 2, after all the optical functional layers are formed, the physical properties of the optical functional film are inspected by the inspection means A that inspects the physical properties of the optical functional film located inline and / or offline of the coating apparatus. .
Although the position of the inspection means A may be located off-line of the coating apparatus, it is preferably incorporated in-line after the last coating film forming means of the coating apparatus from the viewpoint of production efficiency.
The inspection means A mainly inspects the physical properties of the entire optical functional film. Examples of the physical properties of the entire optical functional film include optical properties such as total light transmittance, haze, and reflectance, elastic modulus, surface hardness, and adhesion. Since the present invention is useful for an optical multilayer thin film in which a high degree of accuracy is required for each functional layer, it is preferable that the inspection means A can inspect at least optical properties, and more preferably, it can inspect reflectance.
In the present invention, after all the optical functional layers are formed, the physical properties of the optical functional film are inspected by the inspection means A. Therefore, the physical layer changes in the subsequent steps are taken into consideration for the functional layer formed first. Thus, it is possible to accurately perform the control in step 4 to be described later.
In addition, it is preferable that the test | inspection means A can test | inspect the physical property of each optical functional layer other than test | inspecting the physical property of the whole optical functional film. A reflectance is mentioned as a physical property of each functional layer.

The physical properties can be inspected by using a known measuring device. For example, the optical properties such as total light transmittance, haze, and reflectance can be measured by a device using transmitted light or reflected light. Examples of such a device include Empruner BTR-11 manufactured by Spectra Corp. An in-line spectroscopic measurement system manufactured by Otsuka Electronics Co., Ltd. can be mentioned.
1 is an example of an arrangement of a transmission type measuring device. When a transmission type measuring apparatus is incorporated in-line, a light projecting unit may be set on one surface of the optical functional film and a light receiving unit may be set on the other surface.

<Step 3>
In step 3, the appropriate range of the physical properties of the optical functional film is compared with the inspection result of step 2.
As means for carrying out step 3, there is a means in which the coating apparatus has a database 17 in which the appropriate range of physical properties of the optical functional film is stored, and the inspection result of step 2 is transmitted to the database 17 ( (See FIG. 1). In addition, when the inspection means A is located off-line of the coating apparatus, the inspection means A and the coating apparatus may be connected via a network and the transmission may be performed.
The database has physical properties to be inspected by the inspection means A (for example, the entire physical properties of the optical functional film such as the total light transmittance, haze, and reflectance of the entire optical functional film, or the reflectance of each optical functional layer, etc. It is preferable to store an appropriate range regarding physical properties of each functional layer.

<Step 4>
In Step 4, when the inspection result is out of the appropriate range in Step 3, the optical functional layer is formed by controlling at least one coating film forming condition by the coating film forming condition control means of the coating apparatus.
In order to control the coating film forming conditions, the database and the coating film forming condition control means may be associated with each other, and the following two methods are mainly mentioned. In any method, the database has simulation data for control for returning the physical properties to appropriate values, and selects appropriate control from the simulation data to control the coating film formation condition control means. preferable.

(Method i)
First, when it is determined in Step 3 that the physical properties of the individual optical functional layers are out of the appropriate range, in Step 4, the coating film forming conditions are controlled in order to return the physical properties to the appropriate range.
The control of the coating film forming conditions has simulation data in which the database simulates the difference in the physical property value according to the difference in the factor that affects the physical property of each functional layer. This can be done by instructing the film forming condition control means to change the coating film forming conditions. Examples of the simulation data include simulation data in which a refractive index, a film thickness, and a reflection peak wavelength are associated with each other, and the simulation data can be obtained by a spectroscopic ellipsometer.
The change in coating film formation conditions is a change in the factors that affect the physical properties of each functional layer, and since it differs depending on the physical properties to be adjusted and the coating method used, the discharge rate, coating liquid Solid content, coating liquid composition, coating portion contact pressure, and the like.

For example, in the case where the off-state physical property is reflectance, the database has simulation data simulating the difference in reflectance according to the difference in the factors (refractive index and film thickness) that affect the reflectance, and the simulation Depending on the data, means for controlling the coating film forming conditions so that the reflectance falls within the proper range can be mentioned. Specifically, in order to adjust the refractive index, there is a means for changing the blending ratio of the binder resin and the particles in the functional layer forming composition. In addition, in order to adjust the film thickness, when the coating means is a bar coat, there are means for changing the count of the bar and the solid content of the coating liquid. In the case of die coating, a means for changing the solid content and the flow rate of the coating liquid can be used.
In addition, when the physical property removed is haze, simulation data that simulates the difference in haze according to the difference in factors that affect the haze (coating amount, particle mass ratio in the functional layer coating liquid, etc.) And means for controlling the coating film forming conditions (coating amount, mass ratio of particles in the functional layer coating solution, etc.) so that the haze falls within an appropriate range according to the simulation data.

When it is determined in step 3 that the physical properties of the entire optical functional sheet are out of the appropriate range, the above method i can be adopted if the physical properties of the individual optical functional layers can be inspected at the same time. When the physical properties of the layer are not inspected, the following means can be considered to control the film forming conditions.
(Method ii)
For example, if the off-physical property is an optical physical property, the database has simulation data that simulates the optical physical property of the entire optical functional film according to the physical property and / or dimension of each optical functional layer. (For example, simulation data such as the reflectance of the entire optical functional film according to the refractive index and film thickness of each optical functional layer), which physical properties and / or dimensions of which optical functional layer are out of suitability A means for controlling the film forming conditions is conceivable so that the physical properties and / or dimensions that are deviated from the simulation data fall within the appropriate range.
Examples of the dimensions of the individual optical functional layers include film thickness and surface roughness.

(Other methods)
When the optical functional layer is formed from an ionizing radiation curable resin composition, the degree of curing of the optical functional layer may affect the physical properties of the entire optical functional film. Specifically, when the second photofunctional layer is formed without sufficiently curing the first photofunctional layer, the ionizing radiation curable resin composition that forms the second photofunctional layer is used as the first photofunctional layer. It may penetrate into the functional layer and change the physical properties (particularly optical physical properties) of the entire optical functional film. Further, when the second optical functional layer is formed by sufficiently curing the optical functional layer formed first, the adhesion between the optical functional layers tends to decrease.
For this reason, when it determines with the physical property of the whole optical sheet having remove | deviated from the appropriate range at the process 3, the means which makes a physical property into an appropriate range by controlling the hardening degree at the time of individual optical functional layer formation is mentioned. . The degree of curing of each optical functional layer can be controlled by the amount of ionizing radiation.

In the method for producing the optical functional film of the present invention, the coating device can control the formation conditions of the optical functional layer formed before the last optical functional layer. It is preferable that an optical functional layer formed before the last optical functional layer can be controlled.
When the appropriate values of physical properties and dimensions of each layer are narrow like a multilayer thin film, the control range is limited by the control of only the last coating formation means, so the physical properties of the entire optical functional film can be adjusted to the appropriate values. difficult. On the other hand, by making it possible to control the formation conditions of the optical functional layer formed before the last optical functional layer, the physical property values of the optical functional film can be easily adjusted to the appropriate range.

  As described above, in step 4, the coating film forming conditions of the coating apparatus are controlled so that the physical properties and dimensions of each functional layer have appropriate values. From the viewpoint of easy control, it is preferable to control the film forming conditions in step 4 so as to change the dimensions of the optical functional layer.

<Inspection means B>
Further, in the method for producing the optical functional film of the present invention, the physical properties of the optical functional layer formed by the coating apparatus before the last optical functional layer at the in-line position before the final coating film forming means and / or Or it is preferable to have the test | inspection means B which test | inspects a dimension. Examples of physical properties to be inspected include reflectance and refractive index, and examples of dimensions include film thickness and surface roughness.
By having the inspection means B, it can be confirmed whether the control in the step 4 is appropriately performed. As described above, since it is easier to control the dimension in step 4, it is preferable that the inspection unit B can inspect at least the dimension.

<Steps 5 to 7>
Moreover, in the manufacturing method of the optical functional film of this invention, after the process 4, it is preferable to perform the process of 5-7 below in order.
Step 5: Step of inspecting the physical properties and / or dimensions of the optical functional layer formed before the last optical functional layer with the inspection means B Step 6: Physical properties of the optical functional layer formed before the final optical functional layer and / or Or the process of comparing the suitability range of the dimension and the inspection result of step (5) Step 7: If the test result is out of the suitability range in Step 6, the coating film forming condition control means is controlled to Step of forming an optical functional layer formed before the optical functional layer

By performing Steps 5 to 7, when the control in Step 4 is insufficient, the physical properties and / or dimensions of the individual optical functional layers can be returned to the appropriate values, and the physical property values of the optical functional film are determined to be appropriate. Can be adapted to the range.
Steps 5 and 6 can be performed by the same means as steps 2 and 3 described above. It is preferable to send the inspection result in the inspection means B to the database 17.

For the control in step 7, it is preferable to adopt a method different from the control method in step 4.
Specifically, in step 7, the inspection result of inspection means A at the time of step 2 is compared with the inspection result of inspection means B, and it is determined whether the control of step 4 is excessive or insufficient. However, it can be performed by approaching appropriate control. For example, in order to reduce the film thickness inspected by the inspection means A by 10%, when the discharge amount of the coating liquid is reduced by 10% in Step 4, the film thickness is only 8% thin by the inspection by the inspection means B. If not, it is possible to control the discharge amount of the coating liquid to be further reduced by 2.5%.

As described above, the optical functional film manufacturing method of the present invention can feed back the final inspection result to the coating film formation condition control means when the proper physical property value cannot be satisfied in the final inspection. In addition, the yield of the coating liquid is reduced and the yield is improved, and the production is not repeated, so that the production efficiency can be improved. Further, such an effect can be obtained without being restricted by materials.
For example, in the case where a 5000 m optical functional film is manufactured with the optical functional layer as a three-layer structure of a hard coat layer, a high refractive index layer, and a low refractive index layer, when a defect is found in the final inspection process, In the method (the method of winding up each individual functional layer), all the optical functional film of 5000 m is discarded, and the production is re-started from the formation stage of the hard coat layer. It will be redone from the time of liquid manufacture. On the other hand, in the method for producing an optical functional film according to the present invention, the amount of discarded film is about 100 m at the initial stage of production, the disposal of the coating liquid is not necessary, and the production time is only added to the time for 100 m production (line If the speed is 20m / min, it takes about 5 minutes). Therefore, in this case, compared with the conventional method, the manufacturing method of the present invention reduces the amount of discarded film to about 1/50 and the manufacturing time (time not including the manufacturing time of the coating liquid) to about 1/2. Furthermore, when the coating liquid is reached, the amount of waste can be reduced to substantially zero, and the manufacturing time including the coating liquid is at least ½ or less (unlikely, but considering the dispersion process) Then, it can be set to 1/3 or less.
Further, in the present invention, since the optical functional layer is continuously formed in-line, the number of windings can be minimized, and defects generated on the winding core side and defects caused by dust are reduced. It is possible to improve the yield by reducing the condition setting part at the start of manufacturing and the lead part at the end of manufacturing.

[Optical functional film coating equipment]
The optical functional film coating apparatus of the present invention inspects the physical properties of the optical functional film located after the last coating film forming means and the coating film forming means for continuously forming two or more optical functional layers. Inspection means A, coating film formation condition control means for controlling at least one optical functional layer coating film forming means, a database storing appropriate ranges of physical properties of the optical functional film, the inspection results and the appropriate ranges And means for reflecting the result of the comparison to the coating film formation condition control means.

FIG. 1 is a schematic view showing an embodiment of a coating apparatus for an optical functional film of the present invention.
The coating apparatus of FIG. 1 includes three coating film forming means, and has an inspection means A (14) for inspecting the physical properties of the optical functional film after the last coating film forming means 13. Further, in FIG. 1, each coating film forming unit has a coating film forming condition control unit.
Such a coating apparatus of FIG. 1 sends a transparent base material from the unwinder 15 and conveys it while applying tension to the transparent base material in the coating line, and continuously forms an optical functional layer during the transportation. It is possible.

Moreover, in FIG. 1, the inspection result in the inspection means A (14) can be transmitted to the database 17, and the database 17 stores the suitability value of the whole physical property of the optical functional film and the physical property of each functional layer. An aptitude value 171 of physical properties such as an aptitude value is stored. In FIG. 1, the database 17 stores the simulation data 172 described above.
Further, in FIG. 1, in the database 17, the suitability value 171 of the physical property is compared with the test result of the test means A (14), and if the test result is out of the suitability value, the simulation data 172 Thus, the control for returning the physical properties to the appropriate values is selected, and the coating film forming condition control means can be controlled.
Moreover, it is preferable that the coating apparatus of the optical functional film of this invention has the drying means which is not shown in figure and the irradiation means of the ionizing radiation installed as needed after each coating-film formation means.
Furthermore, the optical functional film coating apparatus of the present invention inspects the physical properties and / or dimensions of the optical functional layer formed before the last optical functional layer at an inline position before the final coating film forming means. It is preferable to have the inspection means B to be used.
In addition, the detail of embodiment of each component of the coating apparatus of the optical functional film of this invention is as having demonstrated in the manufacturing method of an optical functional film.

EXAMPLES Next, although an Example demonstrates this invention still in detail, this invention is not limited at all by these examples. “Part” and “%” are based on mass unless otherwise specified.
<Coating device>
As shown in FIG. 1, three coating film forming means (11, 12, 13), a physical property inspection apparatus A (14) located after the last coating film forming means, and a coating film associated with each coating film forming means. A coating apparatus having a forming condition control means (11a, 11b, 11c), a database 17 storing an appropriate value of physical properties and simulation data, an unwinder 15 and a winder 16 was used.
The coating apparatus is configured to be able to transmit the inspection result from the physical property inspection apparatus A to the database. Further, the database and the coating film formation condition control means are associated with each other, and are configured such that the coating film formation condition control means can be controlled by a control instruction in the database. Further, after each coating device, a dryer (not shown) and an ultraviolet irradiation device are installed.

<Coating film forming means>
A roll coat was used as the coating film forming means (11), and a die coat was used for (12, 13).

<Coating film formation condition control means>
In the coating film forming means, the solid content in the coating liquid, the gap between rolls, the gap between the die and the roll, the draw ratio, the flow rate, the coating speed, the drying temperature, the drying air speed, the ratio of the resin components in the coating liquid. The UV irradiation amount can be adjusted, and this was used as a coating film formation condition control means.

<Adjustment of hard coat layer coating solution>
1 photopolymerization initiator (BASF, Irgacure 127, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methylpropionyl) benzyl] phenyl} -2-methylpropan-1-one) .6%, 58.3% of diluting solvent (methyl isobutyl ketone (MIBK) / cyclohexanone (AN) = 8/2) was added (the amount of the solid content of the final coating solution was 40%) until there was no undissolved residue Stir. 40% of photocurable resin (Arakawa Chemical Co., Ltd., beam set 577) was added and stirred, and stirred until there was no undissolved residue. Finally, 0.1% leveling agent (Daiichi Seika Kogyo Co., Ltd., Seika Beam 10-28 (MB)) is added and stirred, and a solid content measuring device is used to determine whether the total coating solution has a solid content of 40%. confirmed.

<Adjustment of high refractive index layer coating solution>
Photopolymerization initiator (BASF, Irgacure 127) 0.1%, diluting solvent (MIBK / AN / MEK = 4/2/4) 92.8% (solid content of the final coating solution is 3%) The mixture was stirred until there was no undissolved residue. 1% of photocurable resin (Arakawa Chemical Co., Ltd., Beam Set 577) was added and stirred, and stirred until there was no undissolved residue. Furthermore, 0.04% of easy-sliding particles (manufactured by SIK Nanotech, SIRMIBK-H84, solid content 30%, average primary particle size 30 nm), zirconium oxide (manufactured by Sumitomo Osaka Cement Co., Ltd., MZ-230X, solid content 32.5%) , Average primary particle size 15 to 50 nm) 6.1% and leveling agent (manufactured by Dainichi Seika Kogyo Co., Ltd., Seika Beam 10-28 (MB)) 0.03%, respectively. It was confirmed with a solid content measuring device whether the solid content of the liquid was 3.0%.

<Adjustment of low refractive index layer coating solution>
Photopolymerization initiator (BASF, Irgacure 127) 0.2%, diluting solvent (MIBK / AN = 7/3) 93.2% (the amount that the solid content of the final coating solution is 3%), Stir until there is no undissolved residue. Here, photocurable resin (Nippon Kayaku Co., Ltd., KAYARAD-PET-30) 1.5%, reactive silica particles (Nissan Chemical Co., Ltd., MIBK-SD, solid content 30%, average primary particle size 10-15 nm) 5.0%, leveling agent (manufactured by Dainichi Seika Kogyo Co., Ltd., Seika Beam 10-28 (MB)) was stirred immediately after each addition, and the solid content of the entire coating solution was 3.0% It was confirmed with a solid content measuring device.

<Physical property inspection device A>
An in-line spectroscopic measurement system manufactured by Otsuka Electronics Co., Ltd. was installed.

<Appropriate values of physical properties>
Appropriate values for the physical properties of each functional layer were as follows.
Hard coat layer / refractive index 1.52, film thickness 3.5 μm
High refractive index layer / refractive index 1.68, film thickness 55-60 nm
Low refractive index layer / refractive index 1.49, film thickness 50-55 nm

<Simulation data>
Table 1 shows simulation data on the relationship between the gap between rolls and the film thickness of the hard coat layer when the solid content is 40%.
Table 2 shows the simulation data of the peak wavelength of the high refractive index layer calculated by the spectroscopic ellipsometer from the refractive index and film thickness of the high refractive layer.
Table 3 shows the simulation data of the peak wavelength of the high refractive index layer calculated from the refractive index and film thickness of the low refractive layer by a spectroscopic ellipsometer.
Table 4 shows simulation data of the film thicknesses of the high refractive index layer and the low refractive index layer calculated from the solid content of the high refractive index layer coating liquid and the low refractive index layer coating liquid and the volume flow rate of these coating liquids. .

[Example 1]
Using the above coating apparatus, a hard coat layer coating solution was applied onto a transparent polyester film having a thickness of 188 μm (manufactured by Toray, Lumirror U407), dried, and irradiated with ultraviolet rays to form a hard coat layer. After forming the hard coat layer, the high refractive index layer coating solution is continuously applied without being wound, dried, and irradiated with ultraviolet rays to form a high refractive index layer, and then continuously applied to the low refractive index layer coating solution. Was coated, dried, and irradiated with ultraviolet rays to form a low refractive index layer to produce an optical functional film.
In Example 1, the physical property of the optical functional film is inspected by the physical property inspection apparatus A located after the coating means for the low refractive index layer. Control was performed as appropriate.
Specifically, when the reflectance peak wavelength of the high refractive index layer or the low refractive index layer deviates from the appropriate value, the database is based on the reflectance peak simulation data obtained from the relationship between the refractive index and the film thickness. In order to calculate the deviation of the film thickness of the high refractive index layer or the low refractive index layer and adjust the film thickness, the solid content of the coating liquid and / or the volume flow rate of the coating liquid with respect to the coating film formation condition control means Was controlled. Further, when the reflectance could not be within the appropriate range only by adjusting the film thickness, the refractive index was controlled by changing the blending ratio of the coating liquid. For example, when a high refractive index layer coating solution having a refractive index of 1.70 is added, the peak wavelength (where the reflectance is highest) may be at a position of 340 nm in order to aim for a film thickness of 50 nm. When the peak wavelength was 340 nm or more, the flow rate was lowered to reduce the film thickness, and when it was 340 nm or less, the flow rate was raised to increase the film thickness. In addition, when a low refractive index layer coating solution having a refractive index of 1.45 is added, the peak wavelength (where the reflectance is lowest) only needs to appear at a position of 305 nm in order to achieve a film thickness of 50 nm. When the peak wavelength was 305 nm or more, the flow rate was lowered to reduce the film thickness, and when it was 305 nm or less, the flow rate was raised to increase the film thickness. Also, when the surface hardness of the optical functional film is lower than the appropriate value, the gap between the rolls is controlled to increase the film thickness of the hard coat layer, and conversely, the surface hardness of the optical functional film is the appropriate value. When it was higher, the gap between the rolls was narrowed to control the thickness of the hard coat layer.

In Example 1, the film thickness of the hard coat layer was an average value obtained by observing the cross section with a laser microscope and measuring the film thickness at 5 points or more.
Moreover, in Example 1, the measurement of the reflectance of the high refractive index layer and the low refractive index layer in-line using the physical property inspection apparatus A was performed as follows.
[Inline inspection]
In order to prevent back reflection of the optical functional film, a blackboard was placed below the optical functional film, and the reflectance was measured with an in-line spectroscopic measurement system (reflection type) manufactured by Otsuka Electronics.

[Example 2]
An optical functional film was produced in the same manner as in Example 1 except that the physical property inspection apparatus A (14) was removed from the coating apparatus and the physical property inspection similar to that in Example 1 was performed off-line.
In Example 2, the off-line reflectance measurement was performed as follows.
[Offline inspection]
A black tape (manufactured by Yamato Co., Ltd.) is attached to the surface of the optical functional film on which the hard coat layer or the like is not formed, and a visible light region (380 nm) is obtained using a spectrophotometer (MCP3100, manufactured by Shimadzu Corporation). ˜830 nm) is measured.

[Comparative Example 1]
As the coating apparatus of Comparative Example 1, there was used a coating film forming unit having no physical property inspection apparatus A in-line. Using the coating apparatus, a hard coat layer coating solution was applied onto a transparent polyester film having a thickness of 188 μm (manufactured by Toray, Lumirror U407), dried, and irradiated with ultraviolet rays to form a hard coat layer. After forming the hard coat layer, it was wound up once through a sticking prevention film, and the physical properties of the hard coat layer were inspected. Subsequently, formation of a high refractive index layer, winding and physical property inspection were performed, and formation of a low refractive index layer, winding and physical property inspection were further performed to manufacture an optical functional film.

[Comparative Example 2]
As the coating apparatus of Comparative Example 2, one coating film forming means was used, which had the physical property inspection apparatus A in-line, and was able to reflect the in-line inspection result on the coating film forming means. Using this coating apparatus, a hard coat layer coating solution is applied on a transparent polyester film (Toray, Lumirror U407) having a thickness of 188 μm, dried, and irradiated with ultraviolet rays to form a hard coat layer, and the adhesive film is passed through. I wound up once. Next, a high refractive index layer was formed and wound, and a low refractive index layer was formed and wound to produce an optical functional film.
Further, in Comparative Example 2, the physical properties of each layer were inspected by the physical property inspection apparatus A located after the coating film forming means, and when it was out of the suitability value, the control by the coating film forming condition control means was appropriately performed.

In the manufacturing method of the optical functional film of Examples 1 and 2, when the physical properties such as the reflectance and the surface hardness are out of the proper range in the inspection result in the physical property inspection apparatus A, the coating film forming conditions are quickly controlled. Therefore, it was possible to make it within a suitable range, and it was excellent in yield and production efficiency. In particular, in the manufacturing method of the optical functional film of Example 1, since the physical property inspection apparatus A is incorporated in-line, the inspection can be performed quickly, and the yield and production efficiency are further improved. .
Moreover, since the manufacturing method of the optical functional film of Examples 1 and 2 is continuously performed in-line, blocking can be prevented even if the hard coat layer formed first does not include particles that prevent blocking. It was a thing. The easy-slip particles in the high refractive index layers of Examples 1 and 2 were aggregated particles in the high refractive index layer, and the average particle size of the aggregated particles was 100 to 150 nm.

In the manufacturing method of the optical functional film of Comparative Example 1, even if the physical properties of each layer deviate from the appropriate values, the defect cannot be determined until the inspection after winding up each layer. It was redone and the production efficiency was inferior.
Further, in the method for producing the optical functional film of Comparative Examples 1 and 2, even if the physical properties of the hard coat layer and the high refractive index layer are within appropriate values, the physical properties of the individual layers are affected by the effect of the layer to be formed later. In some cases, the physical properties of the optical functional film as a whole deviate from the appropriate values, and in this case, it was difficult to make the physical properties within the appropriate range. For this reason, the yield could not be improved, and the manufacturing was started over from the beginning, resulting in poor production efficiency.
Moreover, since the manufacturing method of the optical functional film of Comparative Examples 1 and 2 is to wind each time each layer is formed, a defect on the core side or a defect due to adhesion of dust due to static electricity occurs each time, The yield was inferior. In addition, the manufacturing method of the optical functional film of Comparative Examples 1 and 2 would cause blocking if a sticking prevention film was not used when winding up after forming the hard coat layer.

1: coating apparatus 11, 12, 13: coating film forming means 11a, 12a, 13a: coating film forming condition control means 14: inspection means A
15: Unwinder 16: Winder 17: Database 171: Appropriate value data 172: Simulation data

Claims (13)

A coating film forming means for continuously forming two or more optical functional layers in-line; an inspection means A for inspecting the physical properties of the optical functional film located in-line and / or off-line of the coating apparatus; and at least one The manufacturing method of an optical functional film which performs the process of 1-4 below in order using the coating apparatus of the optical functional film which has a coating-film formation condition control means which controls the coating-film formation means of an optical functional layer.
Step 1: on a transparent substrate, the process steps 2 to continuously form the two or more optical functional layers: by the inspection unit A, step Step 3 for checking the physical properties of the optical functional film: Properties of optical functional films The step of comparing the suitability range of step 2 and the inspection result of step 2 Step 4: If the inspection result is outside the suitability range in step 3, at least the optical functional layer formed immediately before the inspection means A is formed. one optical functional layer, step that form by controlling the film forming conditions   The coating film formation condition control means of the coating apparatus is capable of controlling the formation conditions of the optical functional layer formed before the last optical functional layer. In the step 4, the coating film formation condition control means controls the coating film formation condition control means. The method for producing an optical functional film according to claim 1, wherein the optical functional layer formed before the last optical functional layer is formed.   The said coating apparatus has the test | inspection means B which test | inspects the physical property and / or dimension of the optical functional layer formed before the last optical functional layer in the in-line position before the last coating film formation means. The manufacturing method of the optical functional film of 2. The manufacturing method of the optical functional film of Claim 3 which performs the process of following 5-7 after the said process 4 in order.
Step 5: Step of inspecting the physical properties and / or dimensions of the optical functional layer formed before the last optical functional layer with the inspection means B Step 6: Physical properties of the optical functional layer formed before the final optical functional layer and / or Alternatively, the process of comparing the dimension suitability range with the test result of step 5 Step 7: If the test result is out of the suitability range in step 6, the film forming condition control means is controlled to control the final optical function Forming an optical functional layer to be formed before the layer   The method for producing an optical functional film according to any one of claims 1 to 4, wherein the inspection means A is located in-line after the last coating film forming means of the coating apparatus.   The method for producing an optical functional film according to claim 1, wherein the two or more optical functional layers are continuously formed on the same surface of the transparent substrate.   The method for producing an optical functional film according to claim 6, wherein the two or more optical functional layers include a plurality of transparent layers having different refractive indexes of layers in contact with each other, and an optical interference function is generated between the plurality of transparent layers. .   The plurality of transparent layers include a high refractive index layer having a refractive index of 1.50 to 2.00 and a thickness of 200 nm or less, and a low refractive index layer having a refractive index of 1.20 to 1.50 and a thickness of 200 nm or less on the transparent substrate side. The manufacturing method of the optical functional film of Claim 7 which it has in order.   The optical functional film according to claim 7 or 8, wherein the two or more optical functional layers further include a hard coat layer, and the hard coat layer is located closer to the transparent substrate than the plurality of transparent layers. Method.   The optical function according to any one of claims 1 to 9, wherein the optical functional layer formed first of the two or more optical functional layers does not contain particles protruding from the surface of the optical functional layer located on the outermost surface. For producing a conductive film. Coating film forming means for continuously forming two or more optical functional layers in-line;
Inspection means A for inspecting the physical properties of the optical functional film located in-line after the last coating film forming means,
Coating film forming condition control means for controlling the coating film forming means of at least one optical functional layer;
A database storing the appropriate range of physical properties of the optical functional film;
A coating device for optical functional film , comprising means for reflecting the result of comparison between the inspection result and the appropriate range to the coating film forming condition control unit , wherein the coating film forming condition of the coating apparatus is controlled. An optical functional film coating apparatus in which the means can control the formation conditions of the optical functional layer formed before the last optical functional layer . The optical functionality according to claim 11, further comprising an inspection unit B that inspects physical properties and / or dimensions of an optical functional layer formed before the final optical functional layer at a position before the final coating film forming unit. Film coating equipment. Furthermore, it has means for reflecting the result of comparing the inspection result in the inspection means B and the suitability range to the coating film formation condition control means for the optical functional layer formed before the last optical functional layer. Item 13. The optical functional film coating apparatus according to Item 11 or 12 .