JP2006258880A - Method for manufacturing antireflection film, and antireflection film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an antireflection film by a coating system capable of forming a stable multilayer antireflection layer without stopping a production line even for long-term continuous manufacture, and to provide an antireflection film. <P>SOLUTION: The method for manufacturing an antireflection film comprises steps of forming at least one layer of an antireflection layer directly or through another layer on a film base material, then measuring the film thickness of the antireflection layer by a measuring means, comparing the thickness with a preliminarily prepared reference value, calculating, sending the result as a feedback to a coating film thickness control system, and producing the film while controlling the coating conditions of the antireflection layer. The method is characterized in that: the film thickness on starting to apply/dry a coating liquid of the antireflection layer is measured by the measuring means which is preliminarily subjected to calibration; subsequently the measuring means is calibrated (corrected) without stopping the process while the coating liquid for the antireflection layer is continuously applied; the film thickness of the antireflection layer is measured by the calibrated measuring means; and the coating liquid for the antireflection layer is continuously applied/dried. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing an antireflection film and an antireflection film, and more particularly, to a method for producing an antireflection film useful for solar cells, liquid crystal image display devices, various display devices, organic EL displays, CRTs, PDPs and the like. And an antireflection film produced by this production method.

  In recent years, the development of thin and light notebook personal computers has progressed, and along with this, the demand for thinner and higher performance protective films for polarizing plates used in display devices such as liquid crystal display devices has increased. In addition, a computer provided with an anti-glare layer for improving visibility, providing an anti-glare layer for preventing reflections and scattering the reflected light with a rough surface to obtain display performance with less glare. Liquid crystal image display devices (liquid crystal displays, etc.) such as word processors have come to be used a lot. As an antireflection technology, the reflection of light at the interface between the laminate and the air is reduced by setting the refractive index and optical film thickness of the layer laminated on the film substrate as an antireflection layer (also called an optical interference layer). It is known that it is effective.

In general, a multilayer antireflection layer provided on a film substrate is composed of two or more layers having a high refractive index layer and a low refractive index layer. TiO ₂ , ZrO are used as materials for the high refractive index layer. ₂ , Ta ₂ O _{5 and the} like, and SiO ₂ , MgF _{2 and the} like are contained as a material for the low refractive index layer. It is known that these multilayer antireflection layers are produced by a dry film forming method using a vacuum, such as a sputtering method, a vacuum deposition method, an ion plating method, a CVD method, or a coating method.

  However, in such a dry film forming method, if the area of the processing substrate is increased, the film forming apparatus becomes very large, so that the apparatus becomes very expensive, and in addition to vacuuming or exhausting. However, there is a demerit that enormous time is spent and productivity cannot be increased. On the other hand, the coating method is useful in terms of high productivity, but there is a problem that it is somewhat difficult to maintain the uniformity of the film thickness of the antireflection layer.

  Conventionally, in the formation of a multilayer antireflection layer by a coating method, each time one layer is formed, the spectral reflectance is measured to calculate the film thickness, and the conditions are reset so that the target film thickness is obtained. Moreover, since measurement is performed for each layer, not only time is taken, but even if the same condition is intended, the film thickness may deviate from the target film thickness. The thickness of each antireflection layer is a thin film of several tens to several hundreds of nanometers. In particular, in the formation of the antireflection layer by coating, the spectral reflectance can be obtained only by changing the wet film thickness by 1 μm with respect to the target film thickness. Not only will it differ, but if it changes by several nanometers, the reflectance will shift, and the reflection spectrum reflected from the surface will differ, resulting in coloration and changes in hue. Further, the yield of the finished film is also deteriorated due to the condition setting. For example, when the reflection becomes large, the surrounding light source or bright objects appear on the screen when using a TV, a personal computer monitor, a car navigation system, etc., and the display content becomes difficult to see. If it is colored or the color is different, it will not only be difficult to see, but will also be visually recognized with a color on the black display part, so that the image on the television screen will be significantly reduced.

  As measures against these, for example, on-line reflectance measurement is performed on the reflectance of at least two wavelengths set in the visible light wavelength region for two or more adjacent antireflection layers having different refractive indexes formed on a film substrate. It is characterized in that it is measured by a vessel, compared with a standard reflectance of a set wavelength prepared in advance, calculated, the result is fed back to each coating film thickness control system, and each coating condition of each antireflection layer is controlled. A method for producing an antireflection film is known (see, for example, Patent Document 1).

  However, the method for producing an antireflection film described in Patent Document 1 has the following problems although it has a considerable effect. When measuring with an on-line reflectance measuring instrument, the baseline of the reflectance measuring instrument that was initially set will be shifted due to heat generation of the detector element due to repeated measurements, temporal variation in the amount of light of the light source, etc. Because of the danger, the following measures are required. 1) Periodically suspend the process periodically, measure the reference using the reference reflector, and make corrections. 2) It is necessary to prepare calibration curve data that can predict a change with time in advance and perform a correction operation on the measured value. In the case of 1), the operation rate is lowered by stopping the process, and the productivity is lowered. In the case of 2), the calibration curve data is not a little different depending on the machine difference, the surrounding environment, the usage situation, etc., so correction in several steps is necessary, and the final reliability is difficult.

Under these circumstances, there is a demand for the development of an antireflection film manufacturing method and an antireflection film by a coating method capable of forming a stable multilayer antireflection layer without stopping the production process even in continuous production for a long time. .
JP 2003-329807 A

  The present invention has been made in view of the above situation, and the object of the present invention is to provide an antireflection film by a coating method capable of forming a stable multilayer antireflection layer without stopping the production process even in continuous production for a long time. It is to provide a manufacturing method and an antireflection film.

  The above object of the present invention has been achieved by the following constitution.

(Claim 1)
After coating or drying at least one antireflection layer coating solution directly or via another layer on the film substrate that is continuously transferred, the antireflection layer is formed. In the method of manufacturing an antireflection film, which is measured by a measuring means, compared with a reference value prepared in advance, calculated, and the result is fed back to the coating film thickness control system and manufactured while controlling the coating conditions of the antireflection layer.
The film thickness of the antireflection layer at the start of application / drying of the coating solution for the antireflection layer is measured by the measuring means calibrated in advance,
Thereafter, without stopping the process during the application of the coating solution for the antireflection layer, the measurement means is calibrated (corrected),
Measure the film thickness of the antireflection layer by the calibrated measuring means,
A method for producing an antireflection film, wherein the coating liquid for the antireflection layer is continuously applied and dried.

(Claim 2)
The method for producing an antireflection film according to claim 1, wherein the measuring means is a reflectance spectroscopy measurement apparatus.

(Claim 3)
The method for producing an antireflection film according to claim 1 or 2, wherein the measuring means is arranged in the width direction of the film substrate in accordance with the measurement location.

(Claim 4)
The method for producing an antireflection film according to any one of claims 1 to 3, wherein the calibration of the measuring means is performed immediately after the joint of the film base is detected while the coating is continued.

(Claim 5)
The method for producing an antireflection film according to any one of claims 1 to 3, wherein the calibration of the measuring means is performed at least once during 5 to 180 minutes while the coating is continued.

(Claim 6)
The calibration of the measuring means is performed immediately after detecting the joint of the film base material during the application, and is performed at least once in 5 to 180 minutes. The manufacturing method of the antireflection film as described in claim | item.

(Claim 7)
7. The calibration of the measuring means includes fixing a baseline reference plate and at least one antireflection layer reference plate, and driving the measuring means to set a baseline. The manufacturing method of the antireflection film of any one of these.

(Claim 8)
7. The calibration of the measurement means includes setting the baseline by fixing the measurement means and moving the baseline reference plate and at least one antireflection layer reference plate. The manufacturing method of the antireflection film of any one of these.

(Claim 9)
The calibration of the measuring means is performed by irradiating light to the baseline reference plate and at least one antireflection layer reference plate via a mirror, and reflecting from the baseline reference plate and the antireflection layer reference plate. The method for producing an antireflection film according to any one of claims 1 to 6, wherein light is read through the mirror and a baseline is set.

(Claim 10)
The method for producing an antireflection film according to any one of claims 1 to 9, wherein the film thickness is measured at least at three places in the width direction of the antireflection layer.

(Claim 11)
The method for producing an antireflection film according to any one of claims 1 to 10, wherein the measuring means is installed on a frame that moves in the width direction of the antireflection layer.

(Claim 12)
An antireflection film produced by the method for producing an antireflection film according to any one of claims 1 to 11.

  It is possible to provide an antireflection film manufacturing method and an antireflection film by a coating method capable of forming a stable multilayer antireflection layer without stopping the production process even for a long continuous production, and improving production efficiency. A high-performance antireflection film can be manufactured.

  Although an embodiment of the present invention will be described with reference to FIGS. 1 to 6, the present invention is not limited to this.

  FIG. 1 is a schematic cross-sectional view showing an example of an antireflection film. FIG. 1A is a schematic cross-sectional view showing an example of an antireflection film having a low refractive index layer on a film substrate. FIG. 1B is a schematic cross-sectional view showing an example of an antireflection film having a layer structure in the order of a high refractive index layer and a low refractive index layer on a film substrate. FIG. 1C is a schematic cross-sectional view showing an example of an antireflection film having a layer structure in the order of a hard coat layer, a high refractive index layer, and a low refractive index layer on a film substrate. FIG. 1D is a schematic cross-sectional view showing an example of an antireflection film having a layer structure in the order of a hard coat layer, a medium refractive index layer, a high refractive index layer, and a low refractive index layer on a film substrate. . FIG. 1E is a schematic cross-sectional view showing an example of an antireflection film having a layer structure in the order of a medium refractive index layer, a high refractive index layer, and a low refractive index layer on a film substrate.

  The antireflection film according to the present invention has at least one high refractive index layer on a transparent support, and further has a low refractive index layer on the transparent support. A hard coat layer can be provided. A description will be given below with reference to FIGS.

  The antireflection film shown in FIG. 1A will be described. In the figure, 1a represents an antireflection film. The antireflection film 1 a includes a transparent film substrate 101 that is a film substrate, and a low refractive index layer 102 having a refractive index smaller than that of the transparent film substrate 101 on the transparent film substrate 101.

  The antireflection film shown in FIG. 1B will be described. In the figure, 1b represents an antireflection film. The antireflection film 1b includes a transparent film substrate 101 as a film substrate, a high refractive index layer 103 in order on the transparent film substrate 101, and a low refractive index layer 102 having a refractive index smaller than the refractive index of the transparent film substrate 101. have.

  The antireflection film shown in FIG. 1C will be described. In the figure, 1c represents an antireflection film. The antireflection film 1c has a refractive index smaller than the refractive index of the transparent film substrate 101 which is a film substrate, the hard coat layer 104, the high refractive index layer 103, and the transparent film substrate 101 in order on the transparent film substrate 101. And a low refractive index layer 102.

  The antireflection film shown in FIG. 1 (d) will be described. In the figure, 1d indicates an antireflection film. The antireflection film 1d has a refractive index lower than the refractive index of the transparent film substrate 101, which is a film substrate, the hard coat layer 104, and the high refractive index layer 103 in order on the transparent film substrate 101. It has a medium refractive index layer 105 having a refractive index larger than the refractive index, a high refractive index layer 103, and a low refractive index layer 102 having a refractive index smaller than that of the transparent film substrate 101.

  The antireflection film shown in FIG. 1 (e) will be described. In the figure, 1e represents an antireflection film. The antireflective film 1e has a refractive index smaller than the refractive index of the high refractive index layer 103 on the transparent film substrate 101 in turn and a refractive index larger than the refractive index of the transparent film substrate 101. It has a middle refractive index layer 105, a high refractive index layer 103, and a low refractive index layer 102 having a refractive index smaller than that of the transparent film substrate 101.

  The hard coat layer 104, the medium refractive index layer 105, the high refractive index layer 103, and the low refractive index layer 102 shown in this figure have characteristics described in JP-A-2001-343505. preferable.

  In the present invention, as shown in FIGS. 1 (a) to (d), it is preferable to laminate on the base film in the order of the middle refractive index layer, the high refractive index layer and the low refractive index layer. Two or more layers having the same refractive index may be laminated, and the total number of layers may be 6 to 9 layers. For example, there may be two or more medium refractive index layers, and layers having different refractive indexes may be laminated without sticking to the above order.

  Each layer of the antireflective layer according to the present invention contains a substance that gives the respective refractive index, or a coating solution containing a substance that has the respective refractive index after layer formation is applied on the substrate film and dried. Is obtained.

  Although the range of the refractive index of each layer of the antireflection layer according to the present invention varies depending on each configuration method, a preferable range of refractive index and film thickness in the case of the configuration shown in FIG. . In the middle refractive index layer, 1.55 or more and less than 1.75 is preferable, more preferably 1.60 to 1.73, and in the high refractive index layer 1.75 to 1.95 is preferable, and more preferably, 1.85 to 1.95, and 1.30 to 1.50 are preferable for the low refractive index layer, and more preferably 1.44 to 1.47.

  The thickness of each refractive index layer is preferably 78 ± 5 nm for the middle refractive index layer, 66 ± 5 nm for the high refractive index layer, and 95 ± 5 nm for the low refractive index layer. In addition, a refractive index shows the value measured with Otsuka Electronics Co., Ltd. FE-3000.

  The reflectance of the antireflection film according to the present invention at a wavelength of 450 nm to 650 nm is preferably 1% or less, more preferably 0.5% or less, and particularly preferably 0.00 to 0.3%. In addition, a reflectance shows the value measured with Otsuka Electronics Co., Ltd. FE-3000.

  In the present invention, the antireflection layer (medium refractive index layer, high refractive index layer, low refractive index layer) shown in FIGS. (Refractive index layer / low refractive index layer, medium refractive index layer / high refractive index layer / low refractive index layer) and antireflection film manufactured by individual manufacturing method and antireflection film having stabilized film thickness It relates to film.

  FIG. 2 is a schematic view showing an example of a method for producing an antireflection film.

  In the figure, 2 indicates an antireflection film manufacturing apparatus. The antireflection film manufacturing apparatus 2 includes a film substrate feeding unit 3, a coating liquid supply unit 4, a coating unit 5, a drying unit 6, a control unit 7, a winding unit 8, and a film substrate joint detector. 9. Reference numeral 301 denotes a roll-shaped film base wound around a winding core, and 302 denotes a fed-out film base.

  The application unit 5 includes a first application unit 501, a second application unit 502, and a third application unit 503. The 1st application part 501, the 2nd application part 502, and the 3rd application part 503 are arrange | positioned corresponding to the number of application | coating liquids apply | coated on the film | membrane base 302 with which it extended | stretched. The coating unit 5 shown in this figure applies three types of coating liquids that form the layer configuration (three layers of a medium refractive index layer, a high refractive index layer, and a low refractive index layer) shown in FIG. Therefore, it is comprised from three application parts, the 1st application part 501-the 3rd application part 503. The 1st application part 501 has the coater 501a which apply | coats the coating liquid for medium refractive index layer formation on the film base | substrate 301 supported by the backup roll 501b. The second application unit 502 includes a coater 502a that applies a coating solution for forming a high refractive index layer onto the middle refractive index layer of the film base 303 on which the formation of the intermediate refractive index layer supported by the backup roll 502b is formed. Yes. The third coating unit 503 applies a coating solution for forming a low refractive index layer on the high refractive index layer of the film substrate 304 formed with the medium refractive index layer and the high refractive index layer, which is supported by the backup roll 503b. It has a coater 503a.

  The coaters 501a to 503a used in the first application unit 501 to the third application unit 503 can regulate the precise supply amount of the coating liquid, and the coating film is not circulated and used, and there is no change in physical properties of the coating liquid. In particular, a flow coater type slide coater, extrusion coater, curtain coater and the like are particularly preferable as the coating method according to the present invention.

  Reference numeral 305 denotes an antireflection film in which a medium refractive index layer, a high refractive index layer, and a low refractive index layer are formed in this order on a film substrate 302, and 306 denotes a roll-shaped antireflection film wound around a winding core. .

  The coating liquid supply unit 4 includes preparation kettles 401 to 403 arranged corresponding to the number of coating liquids to be coated on the film substrate 302. 401 represents a preparation pot for preparing a coating solution for forming a medium refractive index layer, 402 represents a preparation pot for preparing a coating liquid for forming a high refractive index layer, and 403 represents a preparation pot for preparing a coating solution for forming a low refractive index layer. Indicates. The medium refractive index layer forming coating solution prepared in the preparation kettle 401 is supplied to the coater 501a according to the coating amount by the liquid feeding pump 401b through the liquid feeding tube 401a. The coating liquid for forming a high refractive index layer prepared in the preparation kettle 402 is supplied to the coater 502a by the liquid feeding pump 402b in accordance with the coating amount through the liquid feeding pipe 402a. The coating solution for forming a low refractive index layer prepared in the preparation kettle 403 is supplied to the coater 503a in accordance with the coating amount through a liquid feeding pipe 403a. 401c represents a power supply unit of the liquid feed pump 401b, 402c represents a power supply unit of the liquid feed pump 402b, and 403c represents a power supply unit of the liquid feed pump 403b. Examples of the liquid feed pump to be used include a pump using a servo motor and a pump using an inverter motor, and a pump using an inverter motor with a variable on-time frequency (flow rate) is preferable.

  The drying unit 6 includes a first drying unit 601, a second drying unit 602, and a third drying unit 603. The first drying unit 601 to the third drying unit 603 are arranged corresponding to the number of coating liquids applied on the film substrate 301. The drying unit 6 shown in this figure has three types of coating applied to form the layer configuration (three layers of a medium refractive index layer, a high refractive index layer, and a low refractive index layer) shown in FIG. In order to dry the coating liquid, each of the first drying unit 601 to the third drying unit 603 includes three drying units. Reference numeral 601a denotes a drying apparatus for forming a medium refractive index layer having two series of a first series drying apparatus 601a1 and a second series drying apparatus 601a2. Reference numeral 602a denotes a drying apparatus for forming a high refractive index layer having two series of a first series drying apparatus 602a1 and a second series drying apparatus 602a2. Reference numeral 603a denotes a drying apparatus for forming a low refractive index layer having two series of a first series drying apparatus 603a1 and a second series drying apparatus 603a2. The number of series of each of the drying devices 601a to 603a can be appropriately selected from the type of coating liquid to be used, the film thickness, the coating speed, the temperature, the air volume, and the like.

  Reference numeral 601b indicates that the coating liquid for forming the medium refractive index layer applied on the fed film substrate 302 passes through the first series drying apparatus 601a1 and turns without contacting the coating surface when entering the second series drying apparatus 601a2. A non-contact type air roll is shown. Reference numeral 602b denotes a coating surface when the coating liquid for forming a high refractive index layer applied on the middle refractive index layer formed on the film substrate 301 passes through the first series drying apparatus 602a1 and enters the second series drying apparatus 602a2. Shows a non-contact type air roll that turns without touching. A coating liquid 603b is applied when the coating liquid for forming a high refractive index layer applied on the high refractive index layer formed on the medium refractive index layer passes through the first series drying apparatus 603a1 and enters the second series drying apparatus 603a2. A non-contact type air roll that is turned without contacting the surface is shown.

  Reference numeral 601c denotes an ultraviolet irradiation device provided at the end of the second series drying apparatus 601a2 of the drying apparatus 601a, reference numeral 602c denotes an ultraviolet irradiation apparatus provided at the end of the second series drying apparatus 602a2 of the drying apparatus 602a, and reference numeral 603c denotes a drying apparatus. An ultraviolet irradiation device provided at the end of the second series drying device 603a2 of 603a is shown, and the installation of each of these ultraviolet irradiation devices can be appropriately selected depending on the type of coating liquid.

  Reference numeral 601d denotes a cooling device provided at the end of the second series drying apparatus 601a2 of the drying apparatus 601a, reference numeral 602d denotes a cooling apparatus provided at the end of the second series drying apparatus 602a2 of the drying apparatus 602a, and reference numeral 603d denotes the drying apparatus 603a. The cooling devices provided at the end of the second series drying device 603a2 are shown, and these cooling devices are preferably installed to perform application and winding of the next process.

  The control unit 7 includes a first control unit 701, a second control unit 702, and a third control unit 703. The first control unit 701 includes a measuring unit 701a and a control unit 701b. The second control unit 702 includes a measuring unit 702a and a control unit 702b. The third control unit 703 includes a measuring unit 703a and a control unit 703b. The control unit 7 will be described with reference to FIG.

  Each measuring means 701a, 702a, 703a arranges the antireflection layer (medium refractive index layer, high refractive index layer, low medium refractive index layer) formed after the drying at a position where it can be measured. The medium refractive index layer, the high refractive index layer, and the low / medium refractive index layer) are preferably disposed in at least three locations in the width direction. The measurement of the reflectance of each antireflection layer (medium refractive index layer, high refractive index layer, low medium refractive index layer) by each measurement means is performed at intervals of at least 0.5 to 5 seconds by each calibrated measurement means. It is preferable to continuously measure from the start of application of the refractive index layer coating solution to the end of drying after the application of the low and medium refractive index layer coating solution. The calibration of the measurement means and the calibration method of the measurement means will be described with reference to FIGS.

  FIG. 3 is a schematic block diagram showing the relationship between the coating unit and the control unit constituting the antireflection film manufacturing process shown in FIG.

  The relationship between each application part and a control part is demonstrated using this figure. The reflectance of the intermediate refractive index layer formed on the film substrate by the first application portion is measured by measuring means 701a disposed at least at three locations in the width direction of the intermediate refractive index layer. Information on the measured reflectance of at least three locations of the medium refractive index layer is input to the CPU of the control unit 701b. The information input to the CPU is compared with a reference value input in advance in the memory, is subjected to arithmetic processing, and the voltage of the current supply unit 401c is adjusted to control the number of rotations of the motor of the liquid feed pump 401b. It is possible to adjust the supply amount.

  The reflectance of the high refractive index layer applied and formed on the middle refractive index layer in the second application part is measured by the measuring means 702a disposed in at least three places in the width direction of the high refractive index layer. Information on the measured reflectance is input to the CPU of the control unit 702b. The information input to the CPU is compared with a reference value input in advance in the memory, performs arithmetic processing, and adjusts the voltage of the voltage supply unit 402c, thereby controlling the number of revolutions of the motor of the liquid feed pump 402b and applying the information. It is possible to adjust the supply amount of the liquid.

  The reflectance of the low refractive index layer applied and formed on the high refractive index layer in the third application portion is measured by measuring means 703a disposed at least in three positions in the width direction of the low refractive index layer. Information on the measured reflectance is input to the CPU of the control unit 703b. The information input to the CPU is compared with the reference value input in advance in the memory, performs arithmetic processing, and adjusts the current of the current supply unit 403c, thereby controlling the number of revolutions of the motor of the liquid feed pump 403b. It is possible to adjust the supply amount of the liquid.

  FIG. 4 is a schematic view of the measuring means shown in FIG. 2 in which the measuring means is rotated during calibration and the fixed reference plate is measured. 2 is representative of the measuring means 701a (see FIG. 2) disposed in the first control unit 701 (see FIG. 2) because all the measuring means shown in FIG. To do.

  In the figure, reference numeral 303 a denotes a medium refractive index layer formed on the film substrate 302. The measuring unit 701a includes a sensor unit 701a1 having a light projecting unit and a light receiving unit, a light source 701a2, a detector 701a3, a motor 701a4 for rotationally driving the sensor unit 701a1, and reference plates 701a5 and 701a6 for calibration. Have.

  θ represents an irradiation angle of light from the sensor unit 701a1 to the middle refractive index layer 303a. The irradiation angle θ is preferably 90 ± 5 degrees. When the angle exceeds ± 5 degrees, the light irradiated from the sensor part hits the middle refractive index layer, and the amount of reflected light may be significantly lower than ± 5 degrees, making accurate measurement impossible. .

  As the light source 701a2, a tungsten halogen lamp is generally used in the visible region, and an ultraviolet lamp is used on the short wavelength side. In particular, it is preferable to use in combination when accurate measurement is required. If only a tungsten halogen lamp is used, there will be variations in the reflectance value during measurement in the range of 380 to 430 nm, and accurate measurement may not be possible. A method of determining the distance from the converging lens surface of the sensor unit 701a1 to the surface of the middle refractive index layer 303a will be described with reference to FIG.

  The reference plate 701a5 has such smoothness that light applied at a right angle returns to a right angle, and the material is not limited as long as there is no significant change in the surface condition at the time of diameter. The composition ratio of the product is changed, or the characteristics are controlled by a surface processing method (evaporation, coating, etc.) to meet various needs. And in order to raise a measurement precision more, it is more preferable that the reflectance of the to-be-measured object to measure has a near reflectance.

  In this figure, in order to measure the middle refractive index layer 303a, a sapphire plate having a reflectance of 7 to 12% close to the reflectance of the middle refractive index layer is preferable. In the case of the measuring means 702a (see FIG. 2) disposed in the second control unit 702 (see FIG. 2), the reflectance of the high refractive index layer is close to the reference plate corresponding to the reference plate 701a5. A silicone plate or the like having a reflectance of 25 to 40% is preferable. In the case of the measuring means 703a (see FIG. 2) arranged in the third control unit 703 (see FIG. 2), the reference plate corresponding to the reference plate 701a5 is close to the reflectance of the low refractive index layer. A BK7 plate having a reflectivity of 2-5% is preferred. Since the reference plate 701a5 is a baseline reference plate, the mirror is installed at an angle so that the reflectance is 0%. Measuring means 702a (see FIG. 2) disposed in the second controller 702 (see FIG. 2) and measuring means 703a (see FIG. 2) disposed in the third controller 703 (see FIG. 2). ) Also has a reference plate corresponding to the reference plate 701a5.

  The measurement of the reference plate 701a5 and the reference plate 701a6 by the sensor unit 701a1 is performed by rotationally driving the sensor unit 701a1 to the installation position of the reference plate 701a5 and the reference plate 701a6 by the motor 701a4. By measuring the reference plate 701a5 and the reference plate 701a6, the detector 701a3 sets (calibrates) the baseline of the measuring means 701a. Incidentally, in order to measure at least three places in the width direction of the middle refractive index layer 303a, three measuring means 701a shown in the figure are fixedly arranged according to the measuring places. Baseline setting (calibration) is performed in exactly the same way as in this figure.

  Three units arranged in the width direction of the high refractive index layer in order to measure at least three places in the width direction of the high refractive index layer arranged in the second control unit 702 (see FIG. 2) In order to measure at least three locations in the width direction of the low refractive index layer disposed in the means 702a (see FIG. 2) and the third controller 703 (see FIG. 2), the width direction of the low refractive index layer The three measuring units 703a (see FIG. 2) arranged in the base line are set (calibrated) by the same method as the measuring unit 701a of the first control unit 702 (see FIG. 2). ing.

  FIG. 5 is a schematic diagram of an optical system of the sensor unit shown in FIG.

  In the figure, 701a'1 indicates a probe, and 701a'2 indicates a converging lens. f1 represents the diameter of the converging lens 701a'2, L1 represents the distance from the central surface of the converging lens to the middle refractive index layer 303a formed on the film substrate 302, and L2 from the tip of the probe to the center of the converging lens. Indicates the distance. Although the distance L1 from the center plane of the converging lens of the sensor unit 701a1 to the surface of the middle refractive index layer 303a is determined by the diameter of the lens used for the sensor unit 701a1, it cannot be defined, but the relational expression expressed by equation 1) It is possible to calculate by calculation.

Formula 1) L2 = L1 × (f1 / L1-f1)
FIG. 6 is a schematic view of the measuring means shown in FIG. 2 in which the measuring means moves during calibration and a reference plate that is rotatably installed is measured. 2 is representative of the measuring means 701a (see FIG. 2) disposed in the first control unit 701 (see FIG. 2), since all the measuring means shown in FIG. To do.

  In the drawing, reference numerals 701a11 to 701a13 denote three measuring means 701a arranged in the transport direction of the film base 303 having the middle refractive index layer 303a in order to measure at least three places in the width direction of the middle refractive index layer 303a. Each sensor part is shown. Reference numeral 701b1 denotes a pedestal to which the sensor unit 701a11 is attached, which can be moved along the horizontal movement stage 701c1 (in the arrow direction in the figure). Reference numeral 701b2 denotes a pedestal to which the sensor unit 701a12 is attached, which can be moved along the horizontal movement stage 701c2 (in the direction of the arrow in the drawing). Reference numeral 701b3 denotes a pedestal to which the sensor unit 701a13 is attached, and movement (in the direction of the arrow in the drawing) is possible along the stage 701c3 for horizontal movement.

  Each stage 701c1-701c3 is arrange | positioned in parallel with the width direction of the film base | substrate 303 which has the middle refractive index layer 303a. Reference numeral 701d denotes a reference plate mounting plate on which each calibration reference plate can be mounted and rotated. 701d1 represents a reference plate corresponding to the reference plate 701a5 shown in FIG. 4, and 701d2 represents a reference plate corresponding to the reference plate 701a6 shown in FIG. Each sensor unit 701a11 to 701a13 is configured to set (calibrate) a baseline in exactly the same manner as shown in FIG. However, when calibrating each sensor part 701a11-701a13, it is preferable to carry out at the same time.

  In order to measure at least three locations in the width direction of the high refractive index layer disposed in the second control unit 702 (see FIG. 2), 3 disposed in the transport direction of the substrate having the high refractive index layer. In order to measure at least three places in the width direction of the low refractive index layer, which are disposed in the measuring means 702a (see FIG. 2) and the third control unit 703 (see FIG. 2), the low refractive index layer The three measuring means 703a (see FIG. 2) arranged in the conveying direction of the substrate having the base are set (calibrated) by the same method as the measuring means 701a shown in the figure. Yes. A reference plate used for calibration of the measuring means of the method shown in this figure used in the second control unit 702 (see FIG. 2) and the third control unit 703 (see FIG. 2) is shown in FIG. The same reference plate can be used.

  In the calibration of the measuring means shown in this figure, the three measuring means move sequentially along the stage at the time of calibration, and move along the stage in order when the calibration is completed, and then return to the measurement position. It is supposed to return.

  The method for moving the pedestal is not particularly limited, and examples thereof include a method using a rotating roll by a motor incorporated in the pedestal, and a method for attaching the pedestal to the drive belt.

  FIG. 7 is a schematic diagram of a method in which the measurement means shown in FIG. 2 is fixed at the time of calibration and measures the reference plate through a mirror. 2 is representative of the measuring means 701a (see FIG. 2) disposed in the first control unit 701 (see FIG. 2) because all the measuring means shown in FIG. To do.

  In the figure, reference numeral 701e denotes a mirror. Other symbols are the same as those in FIGS. 4 and 6. In the method shown in this figure, the sensor unit 701a1 is fixed, the mirror 701e is moved from a standby position (not shown) during calibration, the optical axis of the sensor unit 701a1 is attached to each calibration reference plate shown in FIG. The reference plate mounting plate 701d that is rotatable is installed at a position where it is refracted so as to be perpendicular to the surface of each reference plate. Further, the reference plate mounting plate 701d is also moved from a standby position (not shown) at the time of calibration so that the optical axis of the light reflected from the mirror 701e is perpendicular to the surface of each reference plate of the reference plate mounting plate 701d. Installed. Calibration of the sensor unit 701a1 can be performed by the same method as shown in FIG. Incidentally, in order to measure at least three places in the width direction of the middle refractive index layer 303a, the other two measuring means arranged in the width direction of the middle refractive index layer 303a are also baselined in the same manner as this figure. Is set (calibration).

  Measuring means 702a (see FIG. 2) disposed in the second controller 702 (see FIG. 2) and measuring means 703a (see FIG. 2) disposed in the third controller 703 (see FIG. 2). (See) can be calibrated in exactly the same way.

  The measuring means according to the present invention is a method for measuring the reflectance of each antireflection layer (medium refractive index layer, high refractive index layer, low refractive index layer) and calculating the thickness of each antireflection layer from the reflectance. As the measuring means to be used, for example, a reflection spectral film thickness meter or the like can be mentioned. In addition to the method of calculating the thickness of each antireflection layer from the reflectance, the reflectance of an arbitrary wavelength and the optical properties (such as luminous reflectance) are measured from the measured reflectance, and the values are used. It is also possible to fade back to the conditions.

The measurement of the reflectance of each antireflection layer (medium refractive index layer, high refractive index layer, low refractive index layer) by each measuring means of the first control unit to the third control unit shown in FIGS. Except during the calibration of the measuring means, it is preferable to perform at least once every 0.5 to 5 seconds. The calibration of each measuring means of the first control unit to the third control unit is performed without stopping the process. It is preferable to carry out at the following timing.
1) Performed immediately after the joint of the film substrate 302 (see FIG. 2) is detected by the joint detector 9 (see FIG. 2).
2) Perform at least once in 5-20 minutes.
3) At least once between 5 to 20 minutes immediately after detection by the joint detector 9 (see FIG. 2) of the joint of the film substrate 302 (see FIG. 2).

The following effects can be obtained by calibrating each measuring means at the above timing.
1) The antireflection layer is always measured by a calibrated measuring machine, and the supply amount of the coating liquid is adjusted based on the measurement information, so that an antireflection film having a stable antireflection layer can be manufactured. Became.
2) By performing calibration without stopping the process, it was possible to prevent one cause of the decrease in operating rate, and it became possible to improve productivity.
3) A calibration curve data that can predict a change with time in advance is prepared, and the complicated work of correcting the measurement value is eliminated, so that highly reliable calibration is possible and process management is facilitated.

  The composition for forming the antireflection layer according to the present invention will be described. The antireflection layer according to the present invention is composed of base film / high refractive index layer / low refractive index layer or base film / medium refractive index layer / high refractive index layer / low refractive index layer. The main substance that determines the refractive index of the medium refractive index layer is a mixture of titanium oxide and resin or silicon oxide, and the main substance that determines the refractive index of the high refractive index layer is titanium oxide. The main substance that determines the refractive index of silicon oxide is silicon oxide or a mixture of silicon oxide and a fluorine compound.

  The precursor for forming titanium oxide or silicon oxide is mainly an organic titanium compound or a monomer, oligomer or hydrolyzate thereof. Further, titanium oxide, silicon oxide, a mixture of titanium oxide and silicon oxide, or silicon oxide and fluorine compound may be used as fine particles without using an organometallic compound. The organometallic compound useful in the present invention is described below. It should be noted that some metal halide compounds may be included in the organometallic compound.

  The organic titanium compound as a precursor for a high refractive index layer or a medium refractive index layer according to the present invention is represented by the following formula (I) or (II).

(I) Ti (R ⁶ ) ₃
(II) Ti (R ⁷ ) ₄
In the formula, R ⁶ is OR ⁹ or X, and R ⁷ is R ⁸ , OR ⁹ , OR ¹⁰ or X, and R ⁹ in R ⁸ and OR ⁹ is an aliphatic hydrocarbon having 1 to 8 carbon atoms. A group, preferably an aliphatic hydrocarbon group having 1 to 4 carbon atoms, OR ¹⁰ is a β-ketone complex group, a β-keto acid complex group, a β-keto acid ester complex group, or a keto acid complex, and X is Halogen. It is essential that at least three of OR ⁹ or X are bonded to Ti in the above formula (I) or (II). The organic titanium compound of the above formula (I) or (II) is present as a monomer, an oligomer, or a hydrolyzate thereof in the coating liquid as a coating composition. This hydrolyzate is considered to have a crosslinked structure by reacting like -Ti-O-Ti-, whereby a cured layer is formed.

  Examples of useful organic titanium compound monomers and oligomers according to the present invention include tetramethoxy titanium, tetraethoxy titanium, tetrapropoxy titanium, tetrabutoxy titanium, methyl trimethoxy titanium, ethyl triethoxy titanium, ethyl tripropoxy titanium, methyl tripropoxy. Titanium, ethyl tributoxy titanium, triethoxy titanium acetoacetonate, dipropoxy titanium diacetoacetonate, chlorotripropoxy titanium, chlorotriethoxy titanium, trimethoxy titanium, triethoxy titanium, tripropoxy titanium, diethoxy titanium acetoacetonate Etc. and di- to 10-mers of these oligomers can be mentioned, but are not limited thereto. The propoxy group may be n- or i-, and the butoxy group may be any of n-, i-, s-, or t. In the above, these are omitted. In the present invention, tetramethoxytitanium, tetraethoxytitanium, tetrapropoxytitanium, tetrabutoxytitanium, and dimer to dimer thereof can be preferably used. Of these, tetrapropoxytitanium, tetrabutoxytitanium, and dimers to dimers thereof are particularly preferable. Further, two or more kinds of organic titanium may be used in combination.

  The monomer, oligomer or hydrolyzate of the organic titanium compound used in the present invention is 50.0% by mass to 98.0% by mass in the solid content contained in the high refractive index layer coating solution or the medium refractive index layer coating solution. % Is preferable. The solid content ratio is more preferably 50% by mass to 90% by mass, and further preferably 55% by mass to 90% by mass. In addition, it is also preferable to add a polymer of an organic titanium compound (a product obtained by previously hydrolyzing an organic titanium compound to be crosslinked) to the coating composition.

  The organic titanium compound is contained in the high refractive index layer coating solution or medium refractive index layer coating solution as the monomer, oligomer, or a partial hydrolyzate thereof, but these organic titanium compounds are gradually added. Self-condensed and crosslinked to form a network bond. Catalysts and curing agents may be used to promote the reaction. These catalysts and curing agents include metal chelate compounds, organometallic compounds such as organic carboxylates, organosilicon compounds having amino groups, and light. And acid generators (photoacid generators), and the like. Among these, aluminum chelate compounds and photoacid generators are particularly preferable. Examples of aluminum chelate compounds are ethyl acetoacetate aluminum diisopropylate, aluminum trisethyl acetoacetate, alkyl acetoacetate aluminum diisopropylate, aluminum monoacetylacetonate bisethylacetoacetate, aluminum trisacetylacetonate, etc. Examples of the acid generator include benzyltriphenylphosphonium hexafluorophosphate, other phosphonium salts, and triphenylphosphonium hexafluorophosphate salts.

  An organosilicon compound as a precursor of silicon oxide useful for a low refractive index layer and a medium refractive index layer according to the present invention is represented by the following formula (III).

(III) Si (R ¹¹ ) ₄
In the formula, R ¹¹ is R ¹² , OR ¹³ , OR ¹⁴ or X, and R ¹³ in R ¹² and OR ¹³ is an aliphatic hydrocarbon group having 1 to 8 carbon atoms, preferably 1 to 4 An aliphatic hydrocarbon group, OR ¹⁴ is a β-ketone complex group, a β-keto acid complex group, or an ester complex group thereof, and X is a halogen. X represents a halogen atom. The organosilicon compound of the above formula (III) is present as a monomer, an oligomer, or a hydrolyzate thereof in the coating liquid as a coating composition. This hydrolyzate is considered to have a crosslinked structure by reacting like -Si-O-Si-, whereby a hardened layer is formed.

Tetramethoxy silicon, tetraethoxy silicon, tetrapropoxy silicon, tetrabutoxy silicon, methyl trimethoxy silicon, ethyl triethoxy silicon, ethyl tripropoxy silicon, methyl tripropoxy silicon, ethyl tributoxy silicon, triethoxy silicon acetoacetonate, dipropoxy silicon aceto Examples include, but are not limited to, acetonate, chlorotripropoxysilicon, chlorotriethoxysilicon, and the like, and di- to 10-mers of these oligomers. The propoxy group may be n- or i-, and the butoxy group may be n-, i-, or s-, and these are omitted in the above. An oligomer is obtained by hydrolyzing these. The hydrolysis reaction can be carried out by a known method. For example, a predetermined amount of water is added to the tetraalkoxysilane, and the by-product alcohol is distilled off in the presence of an acid catalyst. React at 100 ° C. By this reaction, the alkoxysilane is hydrolyzed, followed by a condensation reaction, and a liquid oligomer having 2 or more hydroxyl groups (usually an average degree of polymerization of 2 to 8, preferably 3 to 6) is obtained as a hydrolyzate. I can do it. The degree of hydrolysis can be appropriately adjusted depending on the amount of water used, but in the present invention it is 40 to 90%, preferably 60 to 80%. Here, the degree of hydrolysis is such that in the case of hydrolyzable groups, that is, tetraalkoxysilane, the theoretical amount of water necessary to hydrolyze all alkoxy groups, that is, half the number of ethoxy groups (mol). When the addition of is 100% hydrolysis rate,
Hydrolysis rate (mol%) = (actual added water mol / hydrolysis theoretical water mol%) × 100.

  The oligomer thus obtained usually contains about 2 to 10% by mass of monomers. In the present invention, it may be used in a monomer state or an oligomer state, or a mixture of a monomer and an oligomer may be used. However, since film formation may be difficult, the monomer is flash distilled or vacuum distilled so that the monomer content is 1% by mass or less, preferably 0.3% by mass or less of the total organosilicon compound. Is preferably removed.

  In the present invention, a partial hydrolyzate obtained by adding a catalyst or water to tetraalkoxysilane as described above is used, but a complete hydrolyzate is preferably used rather than a partial hydrolyzate. A hydrolyzate cured by a method such as adding a solvent to the hydrolyzate and then adding the following curing catalyst and water is obtained. As such a solvent, it is preferable to use methanol, ethanol, (n, i-) propanol, (n, i, s-) butanol, octanol or the like in combination of one or more. The amount of the solvent is 50 to 400 parts by mass, preferably 100 to 250 parts by mass with respect to 100 parts by mass of the partial hydrolyzate.

  Examples of the curing catalyst include acids, alkalis, organic metals, metal alkoxides and the like. In the present invention, acids, particularly organic acids having a sulfonyl group or a carboxyl group are preferably used. For example, acetic acid, polyacrylic acid, benzenesulfonic acid, p-toluenesulfonic acid, methylsulfonic acid and the like are used. The organic acid is preferably a water-soluble acid. For example, citric acid, tartaric acid, levulinic acid, formic acid, propionic acid, malic acid, succinic acid, methyl succinic acid, fumaric acid, oxaloacetic acid, pyruvic acid, 2- Oxoglutaric acid, glycolic acid, D-glyceric acid, D-gluconic acid, malonic acid, maleic acid, oxalic acid, isocitric acid, lactic acid and the like are preferably used. Also, benzoic acid, hydroxybenzoic acid, atorvaic acid and the like can be used as appropriate. Further, among these organic acids, a compound having a hydroxyl group and a carboxyl group in one molecule is more preferable. For example, hydroxydicarboxylic acid such as citric acid or tartaric acid is preferably used. The use of organic acids not only eliminates pipe corrosion and safety concerns during production when inorganic acids such as sulfuric acid, hydrochloric acid, nitric acid, hypochlorous acid, and boric acid are used, but also during hydrolysis. A stable hydrolyzate can be obtained without causing gelation. The addition amount of the organic acid is 0.1 to 10 parts by mass, preferably 0.2 to 5 parts by mass with respect to 100 parts by mass of the partial hydrolyzate. Further, the amount of water added may be more than the amount that the partial hydrolyzate can theoretically hydrolyze to 100 mol%, and the amount corresponding to 100 to 300 mol%, preferably 100 to 200 mol%, should be added. The coating composition for the low refractive index layer or the medium refractive index layer thus obtained is extremely stable.

In the present invention, further, the hydrolyzed organosilicon compound is aged to promote hydrolysis, condensation, and formation of a crosslink to form silicon oxide, thus forming a low refractive index layer that is a film. Alternatively, the properties of the medium refractive index layer are excellent. In the aging, the oligomer liquid may be allowed to stand, and the standing time is a time for which the above-described crosslinking proceeds sufficiently to obtain desired film characteristics. Specifically, although depending on the type of catalyst used, 1 hour or more at room temperature for hydrochloric acid, several hours or more for maleic acid, 8 hours to 1 week is sufficient, and usually about 3 days. The ripening temperature affects the ripening speed, and it may be better to take a means of heating to around 20 ° C. in extremely cold regions. In general, ripening progresses quickly at high temperatures, but when heated to 100 ° C. or higher, gelation occurs. Therefore, heating to 50 to 60 ° C. at best is appropriate. In addition to the above, the oligomer used in the present invention may be modified with a monomer, oligomer or polymer of an organosilicon compound having a functional group such as an epoxy group, amino group, isocyanate group or carboxyl group. You may use together with the said oligomer well. Most of the silicon oxide formed in the low refractive index layer or the middle refractive index layer is SiO _x (where x is 2 or less), and is preferably infinitely SiO ₂ .

<binder>
The coating liquid for forming each refractive index layer according to the present invention preferably contains a binder from the viewpoints of coating properties and stability after coating, etc. May not use a binder. Therefore, the solid content ratio of the binder in the coating liquid composition is preferably 20% by mass or less.

  In particular, a medium refractive index layer or a high refractive index layer containing an organic titanium compound is preferably used from the viewpoint of compatibility with an alcohol-soluble acrylic resin as a binder. Thereby, it is possible to obtain a middle refractive index layer or a high refractive index layer free from film thickness unevenness and aggregates. In the low refractive index layer, it is not particularly necessary to use a binder. However, when used, it is preferable to use the above alcohol-soluble binder. In order to set the refractive index of each refractive index layer to a target value, it is better not to use a binder at all, or to adjust the refractive index to the target refractive index, the content of the binder may be adjusted. .

  Useful alcohol-soluble binders are preferably alkyl (meth) acrylate polymers or alkyl (meth) acrylate copolymers, such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl. Homopolymers or copolymers such as acrylate, s-butyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, s-butyl methacrylate are preferably used. The components are not limited to these. Commercially available products of these alcohol-soluble alkyl (meth) acrylate homopolymers or copolymers include dialnal (hereinafter abbreviated as dialnal) BR-50, BR-51, BR-52, BR-60, BR- 64, BR-65, BR-70, BR-73, BR-75, BR-76, BR-77, BR-79, BR-80, BR-82, BR-83, BR-85, BR-87, BR-88, BR-89, BR-90, BR-93, BR-95, BR-96, BR-100, BR-101, BR-102, BR-105, BR-107, BR-108, BR- 112, BR-113, BR-115, BR-116, BR-117, BR-118 (above, manufactured by Mitsubishi Rayon Co., Ltd.) and the like can be used. These monomer components can also be preferably added as a binder for a medium refractive index or high refractive index layer. The refractive index can be adjusted by changing the addition ratio of the binder.

  In addition to the above, the following binders can also be used. Such a binder has two or more polymerizable groups such as a polymerizable vinyl group, allyl group, acryloyl group, methacryloyl group, isopropenyl group, epoxy group, and oxetane ring, and has a crosslinked structure or network by irradiation with active energy rays. An acrylic or methacrylic active energy ray reactive compound, an epoxy active energy ray reactive compound or an oxetane active energy ray reactive compound that forms a structure is preferred. These compounds include monomers, oligomers and polymers. Of these active groups, an acryloyl group, a methacryloyl group or an epoxy group is preferable from the viewpoint of polymerization rate and reactivity, and a polyfunctional monomer or oligomer is more preferable. An alcohol-soluble acrylic resin is also preferably used.

  Examples of the acrylic or methacrylic active energy ray reactive compound include an ultraviolet curable acrylic urethane resin, an ultraviolet curable polyester acrylate resin, an ultraviolet curable epoxy acrylate resin, and an ultraviolet curable polyol acrylate resin. .

  UV curable acrylic urethane resins generally include 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate (hereinafter referred to as acrylate) in products obtained by reacting polyester polyols with isocyanate monomers or prepolymers. It can be easily obtained by reacting an acrylate monomer having a hydroxyl group such as 2-hydroxypropyl acrylate (for example, JP-A-59-151110).

  An ultraviolet curable polyester acrylate resin can be easily obtained by reacting a monomer such as 2-hydroxyethyl acrylate, glycidyl acrylate, or acrylic acid with a hydroxyl group or carboxyl group at the end of the polyester (see, for example, JP-A No. 59-151112).

  The ultraviolet curable epoxy acrylate resin is obtained by reacting a terminal hydroxyl group of an epoxy resin with a monomer such as acrylic acid, acrylic acid chloride, or glycidyl acrylate.

  Examples of the ultraviolet curable polyol acrylate resin include ethylene glycol (meth) acrylate, polyethylene glycol di (meth) acrylate, glycerin tri (meth) acrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, and dipenta. Examples include erythritol pentaacrylate, dipentaerythritol hexaacrylate, and alkyl-modified dipentaerythritol pentaacrylate.

  There are many commercially available UV curable resins such as ADEKA OPTMER KR / BY series: KR-400, KR-410, KR-550, KR-566, KR-567, BY-320B (above, Asahi Denka) Manufactured by Kogyo Co., Ltd.); Koei Hard (hereinafter abbreviated as Koei Hard) A-101-KK, A-101-WS, C-302, C-401-N, C-501, M-101, M-102, T-102, D-102, NS-101, FT-102Q8, MAG-1-P20, AG-106, M-101-C (above, manufactured by Guangei Chemical Industry Co., Ltd.); Seika Beam (hereinafter abbreviated as Seika Bee) PHC2210 (S), PHC X-9 (K-3), PHC2213, DP-10, DP-20, DP-30, P1000, P1100, P1200, P13 0, P1400, P1500, P1600, SCR900 (above, manufactured by Dainichi Seika Kogyo Co., Ltd.); RC-5020, RC-5031, RC-5100, RC-5102, RC-5120, RC-5122, RC-5152, RC-5171, RC-5180, RC-5181 (Dainippon Ink and Chemicals, Inc.) Manufactured by Aurex; 340 clear (manufactured by China Paint Co., Ltd.); Sun Rad H-601 (manufactured by Sanyo Chemical Industries); SP-1509, SP-1507 (manufactured by Showa Polymer Co., Ltd.); RCC-15C (manufactured by Grace Japan Co., Ltd.) Aronix M-6100, M-8030, M-8060 (above, manufactured by Toagosei Co., Ltd.) and the like.

  In order to adjust the refractive index or improve the film quality, it is preferable to add a functional silane compound to each layer of the antireflection layer according to the present invention. By containing this functional silane compound in the refractive index layer, there is an effect of enhancing the adhesion of each layer, and by irradiating the layer with active energy rays, hydrolysis of the metal alkoxide and its hydrolyzate, The condensation reaction is accelerated, and it is effective to form a metal oxide. In particular, when the metal organic alkoxide is a titanium alkoxide compound, acceleration of the condensation reaction is accelerated. When there is no binder in the refractive index layer, the layer has a curing action, and a stable refractive index layer can be obtained.

  Examples of useful functional silane compounds include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, i-propyltrimethoxy. Silane, i-propyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloyloxypropyl Trimethoxysilane, γ-mercaptopropyltriethoxysilane, phenyltrimethoxysilane, vinyltriethoxysilane, 3,4-epoxycyclohexylethyltrimethoxysilane, 3,4-epoxycyclohexyl Ethyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 4,4,4,3,3-pentafluorobutyltrimethoxysilane, 3- (perfluoroethoxy) propyltrimethoxysilane, 3- ( Perfluoropropoxy) propyltriethoxysilane, 3- (2,2,2,3,3,3-hexafluoropropoxy) propyltriethoxysilane, 3- (2,2,3,3,4,4,4- Heptafluoropentoxy) propyltrimethoxysilane, 3- (2,2,3,3,4,4-butoxy) propyltrimethoxysilane, 3- (perfluorocyclohexyloxy) propyltrimethoxysilane, dimethyldimethoxysilane, dimethyl Diethoxysilane, methylphenyldimethoxysilane, diethyldimethoxysilane Diethyldiethoxysilane, di-n-propyldimethoxysilane, di-n-propyldiethoxysilane, di-i-propyldimethoxysilane, di-i-propyldiethoxysilane, diphenyldimethoxysilane, divinyldiethoxysilane, Di-3,3-tetrafluoropropyldimethoxysilane, di (3- (perfluoropropoxy) propyl) dimethoxysilane, di (3- (2,2,3,3,4,4,5,5,6,6) -Dodecafluoroheptoxy) propyl) dimethoxysilane, di-3,3,4,4,4-pentafluorobutyldimethoxysilane, methyltriphenoxysilane, methyltribenzyloxysilane, methyltriphenethyloxysilane, glycidoxymethyl Trimethoxysilane, glycidoxymethyltriethoxysila , Α-glycidoxyethyltrimethoxysilane, α-glycidoxyethyltriethoxysilane, β-glycidoxyethyltrimethoxysilane, β-glycidoxyethyltriethoxysilane, α-glycidoxypropyltrimethoxy Silane, α-glycidoxypropyltriethoxysilane, β-glycidoxypropyltrimethoxysilane, β-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxy Silane, γ-glycidoxypropyltripropoxysilane, γ-glycidoxypropyltributoxysilane, γ-glycidoxypropyltriphenoxysilane, α-glycidoxybutyltrimethoxysilane, α-glycidoxybutyltriethoxy Silane, β-glycidoxybuty Triethoxysilane, γ-glycidoxybutyltrimethoxysilane, γ-glycidoxybutyltriethoxysilane, δ-glycidoxybutyltrimethoxysilane, δ-glycidoxybutyltriethoxysilane, (3,4-epoxy Cyclohexyl) methyltrimethoxysilane, (3,4-epoxycyclohexyl) methyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltripropoxysilane, β- (3,4-epoxycyclohexyl) ethyltributoxysilane, β- (3,4-epoxycyclohexyl) ethyltriphenoxysilane, γ- (3 4-epoxycyclohexyl) Pyrtrimethoxysilane, γ- (3,4-epoxycyclohexyl) propyltriethoxysilane, δ- (3,4-epoxycyclohexyl) butyltrimethoxysilane, δ- (3,4-epoxycyclohexyl) butyltriethoxysilane, Glycidoxymethylmethyldimethoxysilane, glycidoxymethylmethyldiethoxysilane, α-glycidoxyethylmethyldimethoxysilane, α-glycidoxyethylmethyldiethoxysilane, β-glycidoxyethylmethyldimethoxysilane, β- Glycidoxyethylethyldimethoxysilane, α-glycidoxypropylmethyldimethoxysilane, α-glycidoxypropylmethyldiethoxysilane, β-glycidoxypropylmethyldimethoxysilane, β-glycidoxypropylethyldimethoxysilane Γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyldipropoxysilane, γ-glycidoxypropylmethyldibutoxysilane, γ-glycidoxy Propylmethyldiphenoxysilane, γ-glycidoxypropylethyldimethoxysilane, γ-glycidoxypropylethyldiethoxysilane, γ-glycidoxypropylvinyldimethoxysilane, γ-glycidoxypropylvinyldiethoxysilane, ethyltri Methoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, γ-chloropro Pyrtrimethoxysilane, γ-chloropropyltriethoxysilane, γ-chloropropyltriacetoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane , Γ-mercaptopropyltriethoxysilane, β-cyanoethyltriethoxysilane, chloromethyltrimethoxysilane, chloromethyltriethoxysilane, N- (β-aminoethyl) γ-aminopropyltrimethoxysilane, N- (β-amino Ethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldimethoxysilane, N- (β-aminoethyl) γ-aminopropyltriethoxysilane, N- (β-aminoethyl) γ-aminopropylmethyldiethoxysilane , Dimethyldimethoxysilane, phenylmethyldimethoxysilane, dimethyldiethoxysilane, phenylmethyldiethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropylmethyldiethoxysilane, dimethyldiacetoxysilane, γ-methacryloxypropylmethyl Dimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptomethyldiethoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane, glycidoxymethyltrimethoxysilane, glycid Xymethyltriethoxysilane, α-glycidoxyethyltrimethoxysilane, α-glycidoxyethyltriethoxysilane, β-glycidoxyethyltrimeth Sisilane, β-glycidoxyethyltriethoxysilane, α-glycidoxypropyltrimethoxysilane, α-glycidoxypropyltriethoxysilane, β-glycidoxypropyltrimethoxysilane, β-glycidoxypropyltriethoxy Silane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltripropoxysilane, γ-glycidoxypropyltributoxysilane , Γ-glycidoxypropyltriphenoxysilane, α-glycidoxybutyltrimethoxysilane, α-glycidoxybutyltriethoxysilane, β-glycidoxybutyltriethoxysilane, γ-glycidoxybutyltrimethoxysilane , Γ-glycy Xybutyltriethoxysilane, δ-glycidoxybutyltrimethoxysilane, δ-glycidoxybutyltriethoxysilane, glycidoxymethylmethyldimethoxysilane, glycidoxymethylmethyldiethoxysilane, α-glycidoxyethylmethyl Dimethoxysilane, α-glycidoxyethylmethyldiethoxysilane, β-glycidoxyethylmethyldimethoxysilane, β-glycidoxyethylethyldimethoxysilane, α-glycidoxypropylmethyldimethoxysilane, α-glycidoxypropyl Methyldiethoxysilane, β-glycidoxypropylmethyldimethoxysilane, β-glycidoxypropylethyldimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ- Glycidoxypropylmethyldipropoxysilane, γ-glycidoxypropylmethyldibutoxysilane, γ-glycidoxypropylmethyldiphenoxysilane, γ-glycidoxypropylethyldimethoxysilane, γ-glycidoxypropylethyldiethoxy Examples thereof include silane, γ-glycidoxypropylvinyldimethoxysilane, and γ-glycidoxypropylvinyldiethoxysilane. In any case, by irradiating active energy rays to the layer containing these compounds, the condensation of the hydrolyzate of the metal alkoxide compound is promoted, a crosslinked structure can be formed, the layer can be strengthened, and the adhesiveness is also strong. I can do it. This effect is most effective in titanium alkoxide. Two or more of these compounds may be used in combination. In addition to these, a silane coupling agent can also be added.

The active energy ray used in the production method of the antireflection film of the present invention can be used without limitation as long as it is an energy source that activates a compound such as ultraviolet ray, electron beam, and γ ray, but ultraviolet ray and electron beam are preferable, Ultraviolet rays are preferred because they are easy to handle and high energy can be easily obtained. As the ultraviolet light source for irradiating the above-mentioned functional silane compound or the ultraviolet light source for photopolymerizing the ultraviolet reactive compound, any light source that generates ultraviolet light can be used. For example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like can be used. An ArF excimer laser, a KrF excimer laser, an excimer lamp, synchrotron radiation, or the like can also be used. Irradiation conditions vary depending on each lamp, but the irradiation light amount is preferably ²⁰ to 10,000 mJ / cm ² , more preferably 100 to 2,000 mJ / cm ² , and particularly preferably 120 to 2,000 mJ / cm 2. ² .

  When ultraviolet rays are used, the multilayer antireflection layer may be irradiated one by one or after lamination, but from the viewpoint of productivity, it is preferable to irradiate the ultraviolet rays after lamination.

  Moreover, an electron beam can be used similarly. As an electron beam, 50 to 1000 keV, preferably 100 to 100, emitted from various electron beam accelerators such as a cockroft Walton type, a bandegraph type, a resonance transformation type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type. An electron beam having an energy of 300 keV can be given.

  Examples of the solvent used in the coating solution when applying each refractive index layer according to the present invention include alcohols such as methanol, ethanol, 1-propanol, 2-propanol, and butanol, and ketones such as acetone, methyl ethyl ketone, and cyclohexanone. , Aromatic hydrocarbons such as benzene, toluene, xylene, glycols such as ethylene glycol, propylene glycol, hexylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol Glycols such as monobutyl ether, ethylene glycol diethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether Ether such, N- methylpyrrolidone, dimethylformamide, methyl acetate, methyl lactate, ethyl lactate, water, etc. can be mentioned. In particular, alcohols compatible with metal alkoxides such as methanol, ethanol, propanol or butanol are preferably used. Also, by using at least one solvent having a boiling point at 101 kPa (1 atm) of 120 to 180 ° C. and a vapor pressure at 20 ° C. of 2.3 kPa or less in the coating solution, the curing rate is moderately delayed, and after coating This is preferable because it can prevent white turbidity, and can eliminate coating unevenness and improve the pot life of the coating solution. Among these, solvents having an ether bond in the molecule, particularly glycol ethers are preferable. Examples of the glycol ethers include propylene glycol mono (C1 to C4) alkyl ether or propylene glycol (C1 to C4) alkyl ether ester, specifically, propylene glycol monomethyl ether (PGME), Propylene glycol monoethyl ether, propylene glycol mono (n-) propyl ether, propylene glycol monoisopropyl ether, propylene glycol monobutyl ether, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate. Although the example of the boiling point (degreeC) in 101 kPa and the vapor pressure (kPa) in 20 degreeC of these preferable glycol ethers is shown below, it is not limited to these. In addition, the following display shows a solvent name, and the inside of a parenthesis shows the boiling point in 1 atmosphere, and the vapor pressure kPa in 20 degreeC. Specifically, propylene glycol monomethyl ether (121, 0.106), propylene glycol monoethyl ether (132.8, 0.53 or more), propylene glycol monobutyl ether (171.1, 0.13), diethylene glycol dimethyl ether (162 0.40), ethylene glycol monomethyl ether (124.4, 0.78), ethylene glycol methyl ether acetate (145, 0.27), ethylene glycol monobutyl ether (171.2, 0.09), ethylene glycol mono Ethyl ether (135.6, 0.51) ethylene glycol ethyl ether acetate (156.3, 0.16), ethylene glycol diethyl ether (121, 1.25). These solvents are preferably contained in the coating solution in an amount of 1 to 90% by mass of the total organic solvent.

  In order to give scratch resistance to the outermost layer of the antireflection film according to the present invention, it is preferable to add a slipping agent to impart slipperiness. As the slip agent, silicone oil or a wax-like substance is preferably used. As the wax-like substance, for example, a compound represented by the following formula (IV) is preferable.

(IV) R ₁ COR ₂
In the formula, R ₁ is preferably an alkyl group or alkenyl group having 12 or more carbon atoms, and more preferably an alkyl group or alkenyl group having 16 or more carbon atoms. R ₂ represents —OM ₁ group (M ₁ represents an alkali metal such as Na or K or ammonium group), —OH group, —NH ₂ group, or —OR ₃ group (R ₃ has 12 or more carbon atoms) Represents an alkyl group or an alkenyl group, and R ₂ is preferably an —OH group, —NH ₂ group or —OR ₃ group. Specifically, higher fatty acids such as behenic acid, stearamide, and pentacoic acid, or derivatives thereof, and carnauba wax, beeswax, and montan wax containing many of these components as natural products can be preferably used. Further, higher fatty acid amides as disclosed in US Pat. No. 4,275,146, Japanese Patent Publication No. 58-33541, British Patent No. 927,446 or Japanese Patent Application Laid-Open No. 55-126238, and Higher fatty acid esters (esters of fatty acids having 10 to 24 carbon atoms and alcohols having 10 to 24 carbon atoms) as disclosed in JP-A-58-90633, and US Pat. No. 3,933,516 Higher fatty acid metal salts as disclosed in the specification, polyester compounds comprising a dicarboxylic acid having up to 10 carbon atoms and an aliphatic or cycloaliphatic diol as disclosed in JP-A-51-37217 Also, oligopolyesters from dicarboxylic acids and diols disclosed in JP-A-7-13292 can be used. As the silicone oil-like material, polyorganosiloxane as disclosed in JP-B-53-292 is preferably used. As for content in the layer of the slip agent used for a low-refractive-index layer, 0.01-10 mg / m < ² > is preferable. Moreover, you may add to a middle refractive index layer and a high refractive index layer as needed.

  You may add what has a function like surfactant or surfactant to the antireflection layer concerning this invention. For those having a function such as a surfactant, a softening agent, a dispersing agent or the like may be added, which improves the scratch resistance. Among these, anionic or nonionic surfactants are preferable, and examples thereof include dialkylsulfosuccinic acid sodium salt and polyionic alcohol fatty acid ester nonionic surfactant (emulsion). Examples of these commercially available products include Lipooil NT-6, NT12, NT-33, TC-1, TC-68, TC-78, CW-6, TCF-208, TCF-608, NK Oil CS-11, AW-9, AW-10, AW-20, polysofter N-606, paint additive PC-700 (manufactured by Nikka Chemical Co., Ltd.) and the like can be mentioned. In addition, it is preferable to add a low surface tension substance such as a leveling agent or silicone oil to the coating solution as a surfactant. For example, silicone oils described in Table 2 of JP-A No. 2003-121620 such as SH-3749, BY-16-869, KF-101 manufactured by Toray Dow Corning or Shin-Etsu Chemical can be preferably used.

  It is effective and preferable to add the surfactant and the like to the low refractive index layer in the antireflection layer. The addition amount is preferably about 0.01 to 3% by mass, more preferably 0.03 to 1% by mass, based on the solid content contained in the coating solution.

  In order to eliminate sticking with the other surface when the antireflection film according to the present invention is overlaid, it is preferable to contain silicon oxide fine particles in the low refractive index layer. The particle diameter of the silicon oxide fine particles is preferably 0.1 μm or less. For example, Aerosil 200V (manufactured by Nippon Aerosil Co., Ltd.) or the like can be added. In particular, silicon oxide fine particles whose surface is modified with an alkyl group are preferably used. For example, silicon oxide fine particles whose surface is modified with a methyl group which is commercially available as Aerosil R972 or R972V (manufactured by Nippon Aerosil Co., Ltd.) are preferably added. I can do it. In addition, silicon oxide fine particles having a surface substituted with an alkyl group described in JP-A-2001-002799 can also be preferably used, and these are treated with an alkylsilane coupling agent after hydrolysis of the alkoxysilicon oligomer described above. By doing so, the silicon oxide fine particle by which the surface was substituted by the alkyl group can be obtained easily. The silicon oxide fine particles will be described later in the cellulose ester film, and details will be given later. The addition amount of the silicon oxide fine particles is preferably in the range of 0.1 to 40% by mass in terms of the solid content ratio in the low refractive index layer.

The film substrate used for the antireflection film according to the present invention is not particularly limited. For example, a cellulose ester film, a polyester film, a polycarbonate film, a polyarylate film, a polysulfone (including polyethersulfone) system is used. Film, Polyester film such as polyethylene terephthalate, Polyethylene naphthalate, Polyethylene film, Polypropylene film, Cellophane, Cellulose diacetate film, Cellulose acetate butyrate film, Polyvinylidene chloride film, Polyvinyl alcohol film, Ethylene vinyl alcohol film, Syndiotactic polystyrene Film, polycarbonate film, norbornene resin film, polymethylpentene fill , Polyether ketone film, polyether ketone imide film, a polyamide film, a fluororesin film, a nylon film, polymethyl methacrylate film or an acrylic film or the like can be mentioned. Among them, cellulose triacetate film, polycarbonate film, and polysulfone (including polyethersulfone) are preferable, and in the present invention, cellulose triacetate film (for example, Konicattak, product names KC8UX2MW, KC4UX2MW (Konica Corp.) Manufactured)), or a cellulose acetate propionate film is preferably used from the viewpoint of production, cost, transparency, isotropic properties, adhesiveness, and the like. The optical properties of the film substrate, the thickness direction retardation R _t is from 0 to 300 nm, retardation R ₀ in the plane direction film substrate 0~1000nm is preferably used.

  Hereinafter, a cellulose ester film will be described as a particularly preferable film substrate. As the cellulose ester film, a cellulose acetate film, a cellulose acetate butyrate film, and a cellulose acetate propionate film are preferable, and among them, a cellulose acetate film, a cellulose acetate butyrate film, and a cellulose acetate propionate film are preferable.

  As a raw material for cellulose ester film, the substitution degree of the acyl group of the cellulose ester is X, the substitution degree of the acetyl group is Y, and the substitution degree of the propionyl group or butyryl group is Y. Is preferred.

2.3 ≦ X + Y ≦ 2.98
1.4 ≦ X ≦ 2.98
The cellulose ester as a raw material for the cellulose ester film is not particularly limited, and examples thereof include cotton linters, wood pulp (derived from conifers and hardwoods), kenaf and the like. Moreover, the cellulose ester obtained from them can be mixed and used in arbitrary ratios, respectively. When the acylating agent is an acid anhydride (acetic anhydride, propionic anhydride, butyric anhydride), these cellulose esters use an organic solvent such as acetic acid or an organic solvent such as methylene chloride, and It can be obtained by reacting with a cellulose raw material using a protic catalyst.

When the acylating agent is acid chloride (CH ₃ COCl, C ₂ H ₅ COCl, C ₃ H ₇ COCl), the reaction is carried out using a basic compound such as an amine as a catalyst. Specifically, it can be synthesized with reference to the method described in JP-A-10-45804. In addition, the cellulose ester used in the present invention is obtained by mixing and reacting the amount of the acylating agent in accordance with the degree of substitution. In the cellulose ester, these acylating agents react with hydroxyl groups of cellulose molecules. Cellulose molecules are composed of many glucose units linked together, and the glucose unit has three hydroxyl groups. The number of acyl groups derived from these three hydroxyl groups is called the degree of substitution (mol%). For example, cellulose triacetate has an acetyl group bonded to all three hydroxyl groups of the glucose unit (actually 2.6 to 2.98). The butyryl group forming the cellulose acetate butyrate of the cellulose ester may be linear or branched.

  Cellulose acetate propionate containing a propionate group as a substituent has excellent water resistance and is useful as a film for liquid crystal image display devices. The measuring method of the substitution degree of an acyl group can be measured according to the provisions of ASTM-D817-96.

  The number average molecular weight of the cellulose ester is preferably 70,000 to 250,000 because the mechanical strength when molded is high and the dope viscosity is moderate, and more preferably 80,000 to 150,000.

  The organic solvent for dissolving and preparing the cellulose ester solution preferably has good solubility and an appropriate boiling point, such as methylene chloride, methyl acetate, ethyl acetate, amyl acetate, acetone, Tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol, 1,3-difluoro- 2-propanol, 1,1,1,3,3,3-hexafluoro-2-methyl-2-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2,2, Examples include 3,3,3-pentafluoro-1-propanol, nitroethane, 1,3-dimethyl-2-imidazolidinone. That is, organic halogen compounds such as methylene chloride, dioxolane derivatives, methyl acetate, ethyl acetate, as a preferred organic solvent is acetone (i.e., good solvent).

  In addition, as shown in the film forming step by the solution casting film forming method described later, when drying the solvent from the web (film after casting the dope) formed on an endless metal support that moves infinitely, From the viewpoint of preventing foaming in the web, the boiling point of the organic solvent used is preferably 30 to 80 ° C. For example, the good solvent described above has a boiling point of methylene chloride (boiling point 40.4 ° C.), methyl acetate ( Boiling point 56.32 ° C), acetone (boiling point 56.3 ° C), ethyl acetate (boiling point 76.82 ° C), and the like.

  Among the good solvents described above, methylene chloride and methyl acetate, which are excellent in solubility, are preferably used, and it is particularly preferable that methylene chloride is contained in an amount of 50% by mass or more based on the total organic solvent.

  In addition to the organic solvent, the dope preferably contains 0.1 to 30% by mass of an alcohol having 1 to 4 carbon atoms. It is particularly preferable to contain the alcohol at 5 to 30% by mass. After casting the dope described above on a metal support, when the evaporation of the solvent begins, the proportion of alcohol in the dope increases, the web gels, the web becomes strong, and the web is peeled off from the metal support. To be easy to do. When used as a gelling solvent or when the proportion of these is small, there is also a role of promoting dissolution of the cellulose ester of a non-chlorine organic solvent.

  Examples of the alcohol having 1 to 4 carbon atoms include methanol, ethanol, n-propanol, i-propanol, n-butanol, s-butanol, and t-butanol.

  Of these solvents, ethanol is preferred because it has good dope stability, relatively low boiling point, good drying properties, and no toxicity. It is preferable to use a solvent containing 5 to 30% by mass of ethanol with respect to 70 to 95% by mass of methylene chloride. Methyl acetate can be used in place of methylene chloride.

  The cellulose ester film preferably contains the following plasticizer, ultraviolet absorber, antioxidant or fine particles. Both are added and mixed in the dope preparation process.

  Examples of plasticizers include phosphate ester plasticizers, phthalate ester plasticizers, trimellitic acid ester plasticizers, pyromellitic acid plasticizers, glycolate plasticizers, citrate ester plasticizers, and polyesters. A plasticizer or the like can be preferably used. As phosphate ester plasticizers, triphenyl phosphate, diphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate, etc., as phthalate ester plasticizer , Diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, butyl benzyl phthalate, diphenyl phthalate, dicyclohexyl phthalate, etc. As pyromellitic acid ester plasticizers such as phenyl trimellitate and triethyl trimellitate Tetrabutyl pyromellitate, tetraphenyl pyromellitate, tetraethyl pyromellitate, etc., glycolate plasticizers include triacetin, tributyrin, ethyl phthalyl ethyl glycolate, methyl phthalyl ethyl glycolate, butyl phthalyl butyl glycolate As the citrate plasticizer, triethyl citrate, tri-n-butyl citrate, acetyl triethyl citrate, acetyl tri-n-butyl citrate, acetyl tri-n- (2-ethylhexyl) citrate, etc. It can be preferably used. Examples of other carboxylic acid esters include butyl oleate, methylacetyl ricinoleate, dibutyl sebacate, and various trimellitic acid esters.

  As the polyester plasticizer, a copolymer of a dibasic acid such as an aliphatic dibasic acid, an alicyclic dibasic acid, or an aromatic dibasic acid and a glycol can be used. The aliphatic dibasic acid is not particularly limited, and adipic acid, sebacic acid, phthalic acid, terephthalic acid, 1,4-cyclohexyl dicarboxylic acid and the like can be used. As the glycol, ethylene glycol, diethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,4-butylene glycol, 1,3-butylene glycol, 1,2-butylene glycol and the like can be used. These dibasic acids and glycols may be used alone or in combination of two or more.

  In addition, compounds such as epoxy compounds, rosin compounds, phenol novolac type epoxy resins, cresol novolac type epoxy resins, ketone resins, and toluenesulfonamide resins described in Japanese Patent Application No. 2000-338883 are preferably used as plasticizers for cellulose esters. I can do it.

  Among the above compounds, commercially available products from Arakawa Chemical Co., Ltd. KE-604 and KE-610 (acid numbers 237 and 170), KE-100 and KE-356 (abietic acid, dehydroabietic acid and parastolic acid) Esterified products of the mixture, acid numbers 8 and 0) are commercially available. Moreover, G-7 and Hartle RX (mixture of abietic acid, dehydroabietic acid and parastrinic acid, acid values 167 and 168) are commercially available from Harima Kasei Co., Ltd.

  In addition, as a plasticizer, epoxy resin (for example, Araldide EPN1179, Araldide AER260 (manufactured by Asahi Ciba)), ketone resin (for example, Hilac 110, Hilac 110H (manufactured by Hitachi Chemical Co., Ltd.)), para Toluenesulfonamide resins (for example, Topler (Fujiamide Chemical Co., Ltd.)) can also be preferably used. Two or more of these plasticizers may be used in combination, or may be combined with the other plasticizers. The amount of the plasticizer used relative to the cellulose ester is preferably 1 to 20% by mass, particularly preferably 3 to 13% by mass in terms of film performance, processability, and the like.

  As the ultraviolet absorber, those which are excellent in the ability to absorb ultraviolet rays having a wavelength of 370 nm or less and have little absorption of visible light having a wavelength of 400 nm or more are preferable from the viewpoint of good liquid crystal display properties. Examples of preferably used ultraviolet absorbers include, but are not limited to, oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, nickel complex compounds, and the like. Examples of the benzotriazole ultraviolet absorber include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) benzo Triazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) -5 Chlorobenzotriazole, 2- (2′-hydroxy-3 ′-(3 ″, 4 ″, 5 ″, 6 ″ -tetrahydrophthalimidomethyl) -5′-methylphenyl) benzotriazole, 2,2-methylenebis (4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol), 2- (2'-hydroxy 3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2H-benzotriazol-2-yl) -6- (linear and side chain dodecyl) -4-methylphenol (tinuvin) 171), octyl-3- [3-tert-butyl-4-hydroxy-5- (chloro-2H-benzotriazol-2-yl) phenyl] propionate and 2-ethylhexyl-3- [3-tert-butyl-4 A mixture of -hydroxy-5- (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate (tinuvin 109), tinuvin 326, and the like can be mentioned, and any of these can be preferably used. The above chinuvin is manufactured by Ciba Specialty Chemicals.

  Examples of the benzophenone-based ultraviolet absorber include 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, and bis (2-methoxy-4- Hydroxy-5-benzoylphenylmethane) and the like, and any of them can be preferably used.

  As the UV absorber preferably used for the base film according to the present invention, a benzotriazole UV absorber and a benzophenone UV absorber that are highly transparent and excellent in preventing the deterioration of the polarizing plate and the liquid crystal are preferable and unnecessary. Particularly preferred is a benzotriazole-based ultraviolet absorber with less coloring.

Moreover, the ultraviolet absorber whose distribution coefficient described in Unexamined-Japanese-Patent No. 2001-187825 is 9.2 or more improves the surface quality of a film base material, and is excellent also in applicability | paintability. In particular, it is preferable to use an ultraviolet absorber having a distribution coefficient of 10.1 or more. The amount of the UV absorber used is not uniform depending on the type of compound and the use conditions, but is usually preferably 0.2 to 2.0 g, more preferably 0.4 to 1.5 g per 1 m ² of the cellulose ester film. 0.6 to 1.0 g is particularly preferable.

  Fine particles can be added to the cellulose ester film in order to impart slipperiness. Examples of the fine particles include inorganic compound fine particles and organic compound fine particles. As the inorganic compound, a compound containing silicon, silicon oxide, aluminum oxide, zirconium oxide, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate, calcium phosphate, and the like are preferable. Preferably, it is an inorganic compound containing silicon or zirconium oxide, but silicon oxide is particularly preferably used because the turbidity of the cellulose ester laminated film can be reduced. Examples of the silicon oxide fine particles include commercially available products such as Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, and TT600 (Aerosil is a trademark of Nippon Aerosil Co., Ltd.). Can be used. As fine particles of zirconium oxide, for example, commercially available products such as Aerosil R976 and R811 can be used. As an organic compound, polymers, such as a silicone resin, a fluororesin, and an acrylic resin, are preferable, for example, Among these, a silicone resin is preferably used.

  Among the above-described silicone resins, those having a three-dimensional network structure are particularly preferable. For example, Tospearl 103, 105, 108, 120, 145, 3120 and 240 (above Toshiba Silicone Co., Ltd.) ) Etc. can be used.

  The primary average particle diameter of the fine particles added to the cellulose ester film used in the present invention is preferably 20 nm or less, more preferably 5 to 16 nm, and particularly preferably 5 nm from the viewpoint of suppressing haze. ~ 12 nm. These fine particles preferably form secondary particles having a particle diameter of 0.1 to 5 μm and are contained in the cellulose ester film, and the preferable average particle diameter is 0.1 to 2 μm, more preferably 0.2 to 0.6 μm. Thereby, the unevenness | corrugation about 0.1-1.0 micrometer high can be formed in the film surface, and, thereby, appropriate slipperiness can be given to the film surface.

  The primary average particle diameter of the fine particles used in the present invention is measured by observing particles with a transmission electron microscope (magnification 500,000 to 2,000,000 times), observing 100 particles, and using the average value, the primary value is measured. The average particle size was taken. The apparent specific gravity of the fine particles is preferably 70 g / L or more, more preferably 90 to 200 g / L, and particularly preferably 100 to 200 g / L. A larger apparent specific gravity makes it possible to produce a high-concentration dispersion, which is preferable because haze does not increase and it is difficult to form aggregates, and a dope having a high solid content concentration is prepared as in the present invention. In particular, it is particularly preferably used. Silicon oxide fine particles having an average primary particle diameter of 20 nm or less and an apparent specific gravity of 70 g / L or more are, for example, a mixture of vaporized silicon tetrachloride and hydrogen burned in air at 1000 to 1200 ° C. Can be obtained by Further, for example, they are commercially available under the trade names of Aerosil 200V and Aerosil R972V, and these can be used.

  The apparent specific gravity described above is calculated by the following equation by measuring a weight of a predetermined amount of silicon oxide fine particles in a graduated cylinder and measuring the weight.

Apparent specific gravity (g / L) = silicon oxide mass (g) / silicon oxide volume (L)
Examples of the method for preparing a fine particle dispersion include the following three types.

(Preparation method A)
After stirring and mixing the solvent and the fine particles, dispersion is performed with a disperser. This is a fine particle dispersion. The fine particle dispersion is added to the dope solution and stirred.

(Preparation method B)
After stirring and mixing the solvent and the fine particles, dispersion is performed with a disperser. This is a fine particle dispersion. Separately, a small amount of cellulose triacetate is added to the solvent and dissolved by stirring. The fine particle dispersion is added to this and stirred. This is a fine particle addition solution. The fine particle additive solution is thoroughly mixed with the dope solution using an online mixer.

(Preparation method C)
Add a small amount of cellulose triacetate to the solvent and dissolve with stirring. Fine particles are added to this and dispersed by a disperser. This is a fine particle addition solution. The fine particle additive solution is thoroughly mixed with the dope solution using an online mixer.

  Preparation method A is excellent in dispersibility of silicon oxide fine particles, and preparation method C is excellent in that the silicon oxide fine particles are difficult to re-aggregate. Among them, the preparation method B described above is a preferable preparation method that is excellent in both dispersibility of the silicon oxide fine particles and difficulty in reaggregation of the silicon oxide fine particles.

(Distribution method)
The concentration of silicon oxide when the silicon oxide fine particles are mixed with a solvent and dispersed is preferably 5 to 30% by mass, more preferably 10 to 25% by mass, and most preferably 15 to 20% by mass. The higher the dispersion concentration, the lower the turbidity with respect to the added amount, which is preferable because the haze is small and there is no aggregate.

  The solvent used is preferably a lower alcohol, and examples thereof include methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol, and butyl alcohol. Although it does not specifically limit as solvents other than a lower alcohol, It is preferable to use the solvent used at the time of film forming of a cellulose ester.

  The amount of silicon oxide fine particles added to the cellulose ester is preferably 0.01 to 0.3 parts by mass, more preferably 0.05 to 0.2 parts by mass, and more preferably 0.0 to 0.2 parts by mass with respect to 100 parts by mass of the cellulose ester. Most preferred is 08 to 0.12 parts by mass. The larger the added amount, the smaller the dynamic friction coefficient, and the smaller the added amount, the lower the haze and the fewer the aggregates.

  A normal disperser can be used as the disperser. In general, dispersers are broadly divided into media dispersers and medialess dispersers. For dispersion of silicon oxide fine particles, a medialess disperser is preferred because of low haze.

  Examples of the media disperser include a ball mill, a sand mill, and a dyno mill. Examples of the medialess disperser include an ultrasonic type, a centrifugal type, and a high pressure type. In the present invention, a high pressure disperser is preferable. The high pressure dispersion device is a device that creates special conditions such as high shear and high pressure by passing a composition in which fine particles and a solvent are mixed at high speed through a narrow tube. When processing with a high-pressure dispersion apparatus, for example, the maximum pressure condition inside the apparatus is preferably 9.807 MPa or more, more preferably 19.613 MPa or more in a thin tube having a tube diameter of 1 to 2000 μm. Further, at that time, those having a maximum reaching speed of 100 m / second or more and those having a heat transfer speed of 420 kJ / hour or more are preferable.

  The high-pressure dispersion apparatus as described above includes a microfluidizer (trade name) of an ultra-high pressure homogenizer manufactured by Microfluidics Corporation, or a nanomizer (trade name) manufactured by Nanomizer, and a Manton Gorin type high-pressure dispersion apparatus, for example, A homogenizer manufactured by Izumi Food Machinery, UHN-01 manufactured by Sanwa Machinery Co., Ltd., and the like can be mentioned.

  As the antioxidant, a hindered phenol compound is preferably used, and 2,6-di-t-butyl-p-cresol, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl- 4-hydroxyphenyl) propionate], triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3,5 -Di-t-butyl-4-hydroxyphenyl) propionate], 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,5 -Triazine, 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3 -Di-t-butyl-4-hydroxyphenyl) propionate, N, N'-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), 1,3,5-trimethyl -2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tris- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate, etc. I can list them. In particular, 2,6-di-t-butyl-p-cresol, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate] is preferred. Further, for example, hydrazine-based metal deactivators such as N, N′-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl] hydrazine and tris (2,4-di-t A phosphorus processing stabilizer such as (butylphenyl) phosphite may be used in combination. The amount of these compounds added is preferably 1 ppm to 1.0%, more preferably 10 to 1000 ppm in terms of mass ratio with respect to the cellulose ester.

  A description will be given of a solution casting film forming method of a cellulose ester film used as a film substrate according to the present invention. Production of the cellulose ester film by the solution casting film forming method is performed through a dope preparation step, a dope casting step, a solvent evaporation step, a peeling step, a drying step and a stretching step.

  1) Dope preparation step: a step of forming a dope by dissolving the cellulose ester and additives in an organic solvent mainly composed of a good solvent for cellulose ester (in the form of flakes) in a dissolution vessel while stirring. There are various dissolution methods such as a method performed at normal pressure, a method performed below the boiling point of the main solvent, a method performed under pressure above the boiling point of the main solvent, a method performed using a cooling dissolution method, and a method performed at high pressure. After dissolution, the dope is filtered with a filter medium, defoamed, and sent to the next process with a pump. The cellulose ester solution and the above-mentioned additive may be simultaneously dissolved in the cellulose ester solution to form a dope, or a separately prepared additive solution may be mixed with the cellulose ester solution to form a dope. Although there is no restriction | limiting in particular in mixing a cellulose-ester solution and an additive solution, In this invention, the method of mixing with an on-line mixer is preferable, for example, Hi-Mixer (static type in-tube mixer by Toray Engineering Co., Ltd.). ) Is preferable because a uniform dope can be obtained.

  2) Dope casting step: The dope is fed to a pressure die through a pressurized metering gear pump, and the endless metal belt for infinite transfer, for example, a stainless steel belt or a casting position on a metal support such as a rotating metal drum And a step of casting a dope from a pressure die. The surface of the metal support is a mirror surface. Other casting methods include a doctor blade method in which the film thickness of the cast dope film is adjusted with a blade, or a reverse roll coater method in which the film is adjusted with a reverse rotating roll, but the slit shape of the die part is adjusted. A pressure die that is easy to make uniform in film thickness is preferable. Examples of the pressure die include a coat hanger die and a T die, and any of them is preferably used. In order to increase the film forming speed, two or more pressure dies may be provided on the metal support, and the dope amount may be divided and stacked.

  3) Solvent evaporation step: The step of evaporating the solvent by heating the web on the metal support until the web becomes peelable from the metal support. In order to evaporate the solvent, there are a method of blowing air from the web side and / or a method of transferring heat from the back side of the metal support by a liquid, a method of transferring heat from the front and back by radiant heat, and the like. However, the drying efficiency is preferable. A method of combining them is also preferable. In the case of backside liquid heat transfer, it is preferable to heat at or below the boiling point of the organic solvent having the lowest boiling point or the organic solvent having the lowest boiling point.

  4) Peeling step: This is a step of peeling the web in which the solvent has evaporated on the metal support at the peeling position. The peeled web is sent to the next process. If the residual solvent amount of the web at the time of peeling (the following formula) is too large, peeling will be difficult, or conversely, if it is peeled off after sufficiently drying on the metal support, part of the web will be peeled off in the middle .

  There is a gel casting method (gel casting) as a method for increasing the film forming speed (the film forming speed can be increased because the film is peeled off while the residual solvent amount is as large as possible). For example, a poor solvent for the cellulose ester is added to the dope, and the dope is cast and then gelled, and the temperature of the metal support is lowered to gel. By gelling on a metal support and increasing the strength of the film at the time of peeling, peeling can be accelerated and the film forming speed can be increased. The web can be peeled in the range of 5 to 150% by mass depending on the strength of the web on the metal support, the length of the metal support, etc. If it is too soft, the flatness at the time of peeling will be impaired, and slippage and vertical stripes due to peeling tension will easily occur, and the amount of residual solvent will be determined by the balance between economic speed and quality. Therefore, in the present invention, the temperature at the peeling position on the metal support is 10 to 40 ° C., preferably 15 to 30 ° C., and the residual solvent amount of the web at the peeling position is 10 to 120% by mass. Is preferred. The amount of residual solvent after peeling can be expressed by the following formula.

Residual solvent amount (% by mass) = {(MN) / N} × 100
Here, M is the mass of the web at an arbitrary point, and N is the mass when M is dried at 110 ° C. for 3 hours.

  5) Drying and stretching step: After peeling, the web is generally used by using a drying device that conveys the web alternately through a plurality of vertically arranged rolls and / or a tenter device that clips and conveys both ends of the web with clips. To dry. As a drying means, hot air is generally blown on both sides of the web, but there is also a means for heating by applying a microwave instead of the wind. Too much drying tends to impair the flatness of the finished film. Throughout, the drying temperature is usually in the range of 40 to 250 ° C. The drying temperature, the amount of drying air, and the drying time differ depending on the solvent used, and the drying conditions may be appropriately selected according to the type and combination of the solvents used.

  In the present invention, it is preferable to stretch the web at least in the width direction using a tenter dryer. Particularly, when the amount of residual solvent after peeling is 3 to 40% by mass, 1.01 to 2.5 in the width direction. It is preferable to stretch it twice. More preferably, it is biaxially stretched in the width direction and the longitudinal direction, and it is desirable to stretch each by 1.01 times to 2.5 times. Furthermore, by knurling before winding, deterioration of the winding shape can be avoided during storage of the antireflection film in roll form. In this invention, it is preferable to give what is called a knurling process which gives an unevenness | corrugation to the both ends of the width direction of a elongate film, and makes an edge part bulky. Here, the knurling height is defined as follows.

Ratio X (%) = (a / d) × 100 of the film thickness (d: μm) of the knurling height (a: μm)
In the present invention, X is preferably in the range of 1 to 25%, more preferably 5 to 20%, and particularly preferably 10 to 15%.

  The antireflection film according to the present invention has a backcoat layer on the side opposite to the side on which the antireflection layer is coated and a clear hard coat layer or antireflection film on the side of the antireflection layer before coating the above-mentioned antireflection layer. It is preferable to apply a glare layer in advance.

  The back coat layer is coated to impart functions such as slipperiness of the antireflection film, prevention of blocking of the front and back surfaces in a rolled state, curl control, and prevention of static electricity. In order to prevent slipping and to prevent blocking, there are a method in which fine particles are added to the film in advance as described above, and a method in which a back coating layer is provided by applying a coating solution containing fine particles. The back coat layer preferably contains a binder resin and fine particles. The fine particles may be organic or inorganic compounds, such as silicon oxide, titanium oxide, aluminum oxide, zirconium oxide, calcium carbonate, kaolin, talc. Inorganic fine particles such as calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate, calcium phosphate, and the like, and as organic fine particles, polymethacrylic acid methyl acrylate resin powder, acrylic styrene resin powder, polymethyl Methacrylate resin powder, silicone resin powder, polystyrene resin powder, polycarbonate resin powder, benzoguanamine resin powder, melamine resin powder, polyolefin resin powder, polyester resin powder, polyamide resin powder Polyimide resin powder or polyfluoroethylene resin powder, can be mentioned cross-linked polymer fine particles, these can be added to UV curable compositions. The average particle size of these fine particle powders is preferably 0.005 to 1 μm, particularly preferably 0.01 to 0.1 μm. The ratio of the ultraviolet curable resin and the fine particle powder is desirably blended so that the fine particle powder is 0.1 to 10 parts by mass with respect to 100 parts by mass of the resin. The surface roughness of the ultraviolet curable coating layer formed in this manner varies depending on the purpose and type, but the center line average surface roughness Ra (supra) is 1 if Ra is a clear hard coat layer described later. If it is about-50 nm and the below-mentioned anti-glare layer, about 0.1-1 micrometer is preferable.

  Of these, silicon oxide is preferable because it can be used without increasing the haze of the film. The content is preferably 0.04 to 0.3% by mass relative to the base film material. It is preferable to use fine particles such as silicon oxide that are surface-treated with an organic substance because haze can be reduced. Preferred metal organics for the surface treatment include halosilanes, alkoxysilanes (especially alkoxysilanes having a methyl group), silazane, and siloxane. The larger the average particle size of the fine particles, the greater the mat effect, whereas the smaller the average particle size, the better the transparency. Therefore, the average particle size of the primary particles of the preferable fine particles is 5 to 50 nm, more preferably 7 to 16 nm. Examples of the fine particles of silicon oxide include Aerosil 200, 200V, 300, R972, R972V, R974, R202, R812, OX50, TT600, etc., preferably Aerosil 200V, R972, as described above. , R972V, R974, R202, R812. Two or more kinds of these fine particles may be used in combination. When using 2 or more types together, it can mix and use in arbitrary ratios. In this case, fine particles having different average particle sizes and materials, for example, AEROSIL (Aerosil) 200V and R972V can be used in a mass ratio of 0.1: 99.9 to 99.9: 0.1.

  Examples of the binder resin used in the backcoat layer coating composition include vinyl chloride / vinyl acetate copolymer, vinyl chloride resin, vinyl acetate resin, vinyl acetate / vinyl alcohol copolymer, partially hydrolyzed vinyl chloride / acetic acid. Vinyl copolymer, vinyl chloride / vinylidene chloride copolymer, vinyl chloride / acrylonitrile copolymer, ethylene / vinyl alcohol copolymer, chlorinated polyvinyl chloride, ethylene / vinyl chloride copolymer, ethylene / vinyl acetate copolymer Vinyl polymers or copolymers such as coalescence, cellulose ester resins such as nitrocellulose, cellulose acetate propionate, cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate resin, maleic acid and / or Or Copolymer of acrylic acid, acrylate copolymer, acrylonitrile / styrene copolymer, chlorinated polyethylene, acrylonitrile / chlorinated polyethylene / styrene copolymer, methyl methacrylate / butadiene / styrene copolymer, acrylic resin, polyvinyl Acetal resin, polyvinyl butyral resin, polyester polyurethane resin, polyether polyurethane resin, polycarbonate polyurethane resin, polyester resin, polyether resin, polyamide resin, amino resin, styrene / butadiene resin, rubber resin such as butadiene / acrylonitrile resin, silicone type Resins, fluorine resins and the like can be mentioned, but are not limited thereto. As acrylic resins, Acrypet MD, VH, MF, V (manufactured by Mitsubishi Rayon Co., Ltd.), Hyperl M4003, M-4005, M-4006, M-4202, M-5000, M-5001, M-4501 (manufactured by Negami Kogyo Co., Ltd.), the above-mentioned Dianar BR-102 (manufactured by Mitsubishi Rayon Co., Ltd.), and the like. Particularly preferably, cellulose ester resins such as diacetyl cellulose and cellulose acetate propionate are used.

  Examples of the organic solvent used in the back coat layer coating composition as a mixed composition of the binder resin and the fine particles as described above include benzene, toluene, xylene, dioxane, acetone, methyl ethyl ketone, N, N-dimethylformamide, and acetic acid. Examples include methyl, ethyl acetate, trichloroethylene, methylene chloride, ethylene chloride, tetrachloroethane, trichloroethane, and chloroform. Examples of the solvent that is not dissolved include methanol, ethanol, n-propyl alcohol, i-propyl alcohol, and n-butanol.

  The anti-curl function is imparted to the back coat layer by coating the base film with a back coat layer coating composition containing an organic solvent that dissolves or swells the base film material.

  The antireflection film according to the present invention may be provided with a hard coat layer or an antiglare layer in advance before the antireflection layer is applied. Further, an antifouling layer may be applied thereon after forming the antireflection layer. The clear hard coat layer or the antiglare layer is a layer formed by polymerizing a component containing at least one unsaturated ethylenic monomer, and it is preferable to use an active energy ray-curable composition or a thermosetting composition. In particular, it is preferable to use an active energy ray-curable composition. Here, the active energy ray-curable composition is a composition mainly containing an unsaturated ethylenic monomer, or a composition containing a compound having an unsaturated ethylenic group and a relatively large molecular weight (usually referred to as a resin). In the composition, a hardened layer is formed by a crosslinking reaction or the like by irradiation with active energy rays such as ultraviolet rays or electron beams. As the active energy ray-curable composition, an ultraviolet curable composition, an electron beam curable composition, and the like can be cited as representative examples, and even a composition that is cured by irradiation with an active energy ray other than ultraviolet rays or electron beams. Good. The active energy ray curable composition is the same as that described in the above-mentioned antireflection layer, and therefore will be omitted.

  Among these, the ultraviolet curable composition contains a photopolymerization initiator or a sensitizer and can be cured by ultraviolet rays. Examples of the photopolymerization initiator include acetophenone, benzophenone, hydroxybenzophenone, Michler's ketone, α-amyloxime ester, thioxanthone, and derivatives thereof. Further, when using an epoxy acrylate photopolymerization initiator, a sensitizer such as n-butylamine, triethylamine, tri-n-butylphosphine can be used. For light sources from the near ultraviolet region to the visible light region, use can be made possible by incorporating a sensitizer having an absorption maximum in those regions into the composition.

  Examples of the organic solvent used in the ultraviolet curable composition coating solution include hydrocarbons such as cyclohexane, alcohols such as methanol, ethanol, isopropyl alcohol, and isoamyl alcohol; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; Esters such as methyl acetate and ethyl acetate; glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monoisopropyl ether, propylene glycol monoisobutyl ether, etc. The propylene glycol monoalkyl ether described above can be selected as appropriate or used in combination. Is preferably contains a propylene glycol monoalkyl ether esters least 5 wt%, it is preferable to use a mixed organic solvent containing these 5-80 wt%.

  After the UV curable composition coating liquid is applied and dried, or in a freshly dried state, the UV light source is irradiated to the above energy value to cause a curing reaction. The irradiation time at this time varies depending on the transfer speed of the substrate, the composition of the coating solution, the coating thickness, etc., but it is generally preferable that irradiation and curing be completed in about 0.5 seconds to 5 minutes, and 3 seconds to 2 Minutes are more preferred.

  As a method of applying a clear hard coat layer, an antiglare layer, or a back coat layer to a base film, known methods such as a gravure coater, spinner coater, wire bar coater, roll coater, reverse coater, extrusion coater, air doctor coater, etc. Can be used. The liquid film thickness (also referred to as wet film thickness) at the time of application is about 1 to 100 μm, preferably 0.1 to 30 μm, and more preferably 0.5 to 15 μm.

  Examples The effects of the present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

Example 1
An antireflection film was produced by the method described below.

[Production of cellulose ester film]
Various additive solutions and cellulose ester solutions were prepared and mixed as described below to prepare a dope, and a cellulose ester film was prepared by a solution casting film forming method.

<< Preparation of silicon oxide dispersion A >>
Aerosil R972V 1kg
Ethanol 9kg
The above was stirred and mixed with a dissolver for 30 minutes, and then dispersed using a Manton Gorin type high-pressure dispersion device to prepare a silicon oxide dispersion A.

<< Preparation of Additive Liquid A >>
Cellulose triacetate (acetyl group substitution degree 2.88) 6kg
Methylene chloride 140kg
The above was put into a pressure-type airtight container, completely dissolved with heating and stirring, and filtered. To this, 10 kg of the above silicon oxide dispersion A was added with stirring, and the mixture was further stirred for 30 minutes, followed by filtration to prepare additive liquid A.

<< Preparation of Cellulose Ester Solution A >>
440 kg of methylene chloride
Ethanol 35kg
Cellulose triacetate (acetyl group substitution degree 2.88) 100 kg
9 kg of triphenyl phosphate
Ethyl phthalyl ethyl glycolate 2kg
Tinuvin 326 (Ciba Specialty Chemicals) 0.3kg
Tinuvin 109 (Ciba Specialty Chemicals) 0.5kg
Tinuvin 171 (Ciba Specialty Chemicals) 0.5kg
The above-mentioned solvent was put into a closed container, the remaining materials were added while stirring, and completely dissolved while heating and stirring to obtain a cellulose ester solution A. After the temperature was lowered to the casting temperature and allowed to stand overnight, a defoaming operation was performed, and then the solution was added to Azumi filter paper No. 1 manufactured by Azumi Filter Paper Co., Ltd. Filtered using 244.

<< Preparation of Dope A >>
3 kg of this cellulose ester solution A and additive solution A were mixed, mixed for 10 minutes with an on-line mixer (Toray Co., Ltd., static type in-tube mixer Hi-Mixer, SWJ), and filtered to prepare Dope A.

  After the dope A was filtered, the dope A at 35 ° C. was sent to the casting die with a precision metering pump, and uniformly cast on an endless stainless steel belt that moved infinitely in the solution casting film forming apparatus. The temperature of the stainless steel belt was 35 ° C. The web is dried by heating with 39 ° C hot water from the back side of the stainless steel belt, and then heated by blowing 40 ° C hot air from many slits from the back side of the stainless steel belt. And the web was peeled from the stainless steel belt. Hot air of 45 to 55 ° C. was applied to the web side on the stainless steel belt. At the time of peeling, the wind was changed to 15 ° C. The residual solvent amount of the web was 80% by mass. After peeling from the stainless steel belt, after drying for 1 minute in a drying zone maintained at 80 ° C., when the residual solvent amount becomes 3 to 10% by mass, the both ends of the web are gripped, using a stretching tenter, While heating at 100 ° C, the film was stretched 1.15 times in the width direction, the gripping at both ends was released, and drying was completed in a 125 ° C drying zone while being transported by many rolls. A 10 μm knurling process was performed to produce a cellulose ester film having a thickness of 80 μm. The film width was 1300 mm, and the take-up length was 3000 m with a joining with an aluminum vapor-deposited tape every 500 m.

[Production of cellulose ester film having a back coat layer]
The back coat layer coating composition A prepared below was extruded to the A side of the cellulose ester film prepared above (the side on the air side of the web during the web drying with a stainless steel belt) so as to have a wet film thickness of 14 μm. It was coated with a coater, dried at 85 ° C. and wound up to produce a cellulose ester film having a back coat layer.

<Preparation of Backcoat Layer Coating Composition A>
Acetone 30 parts by weight Ethyl acetate 45 parts by weight Isopropyl alcohol 10 parts by weight Diacetylcellulose 0.6 part by weight 2% acetone dispersion of Aerosil 200V 0.2 part by weight [Preparation of cellulose ester film having clear hard coat layer]
Using the wire bar coater on the B side (the belt side surface of the web being dried on the stainless steel belt) of the cellulose ester film having the back coat layer produced above, the following clear hard coat layer composition A is liquid After coating with an extrusion coater to a film thickness of 13 μm, and then drying in a drying section set at 80 ° C., the film was irradiated with ultraviolet rays at 120 mJ / cm ² and a center line average surface roughness of 3 μm in dry film thickness ( Ra) A cellulose ester film having a 13 nm clear hard coat layer was prepared and wound.

<Clear hard coat layer composition A>
Dipentaerythritol hexaacrylate monomer 60 parts by mass Dipentaerythritol hexaacrylate dimer 20 parts by mass Components of dipentaerythritol hexaacrylate trimer or more
20 parts by mass Dimethoxybenzophenone 4 parts by mass Ethyl acetate 45 parts by mass Methyl ethyl ketone 45 parts by mass Isopropyl alcohol 60 parts by mass

[Preparation of antireflection film]
(Preparation of antireflection film production equipment)
The antireflection film manufacturing apparatus shown in FIG. 2 was used.

(Preparation of measurement means)
As a measuring means, a halogen lamp is used as a light source, a sensor having a light projecting portion and a light receiving portion having a lens diameter of 25.4 mm, and a reflectance spectrum measuring type having a detector (CPD7000 type manufactured by Otsuka Electronics Co., Ltd.) are used. Then, the angle at which the optical axes intersect with each antireflection layer was set to 90 °, and the antireflection layer was arranged in three places in the width direction of the antireflection layer on the frame of the antireflection film manufacturing apparatus.

(Calibration of measuring means before starting application)
The calibration of the measuring means of each control unit provided in the first coating unit to the third coating unit of the antireflection film manufacturing apparatus shown in FIG. 2 was calibrated by the method shown in FIG. 4 before starting the coating. Calibration of the measuring means for measuring the middle refractive index layer uses a sapphire plate with a reflectance of 12% as a reference plate close to the reflectance of the middle refractive index layer, and a reflectance of 0% as a reference plate for the baseline. The calibration was performed by irradiating the mirror installed so that

  The calibration of the measuring means for measuring the high refractive index layer uses a silicon vapor deposition plate with a reflectance of 35% as a reference plate close to the reflectance of the high refractive index layer, and the reflection of the light projection becomes 0 for the baseline. As shown in FIG.

  The calibration of the measuring means for measuring the low refractive index layer uses BK7 having a reflectance of 4% as a reference plate close to the reflectance of the low refractive index layer so that the reflected light of the base line is zero. Irradiation to the installed mirror was performed for calibration.

(Calibration of measuring means during application)
The calibration of the measuring means of each control unit provided in the first coating unit to the third coating unit of the antireflection film manufacturing apparatus shown in FIG. 2 is performed under calibration conditions as shown in Table 1 while coating is being performed. The baseline was calibrated by the method shown in FIG. The reference plate used for calibration was the same as that used for calibration of the measuring means before coating.

(Applying each antireflection layer)
Medium refractive index layer formed on the clear hard coat layer on the clear hard coat layer of the cellulose ester film having the prepared back coat layer and clear hard coat layer using the prepared antireflection film production apparatus, The measurement results obtained by measuring the reflectivity of the high refractive index layer and the low refractive index layer using the calibration means calibrated under the calibration conditions shown in Table 1 are fed back to the control means of each control unit. Apply while controlling the supply amount of the coating liquid for the refractive index layer, the coating liquid for the high refractive index layer, and the coating liquid for the low refractive index layer, and the medium refractive index layer, high refractive index layer, low An antireflection film having a refractive index layer in this order was prepared, and sample No. 101-105.

<Medium refractive index layer>
On the clear hard coat layer of the cellulose ester film having the clear hard coat layer obtained above, the following medium refractive index layer composition is applied by an extrusion coater at the first application part so that the dry film thickness becomes 100 nm. Then, after drying at 80 ° C. in the first drying section, drying is further performed at 120 ° C., cooling is performed in the cooling section after the drying, and ultraviolet rays are 175 mJ / hour using an ultraviolet irradiation device of a high-pressure mercury lamp (80 W). Irradiation at cm ² formed a medium refractive index layer. Measure the reflectance with a measuring means prepared from the middle refractive index layer side of a cellulose ester film having a middle refractive index layer, input each measured value to the control means, and calculate the difference from the preset setting value. Then, according to the result, the supply amount of the medium refractive index layer coating solution to the extrusion coater was controlled by controlling the number of revolutions of the liquid feed pump, and the coating amount was corrected to perform coating. The measurement of the medium refractive index layer by the measuring means was performed once per second. The coating speed was 20 m / min.

<< Medium Refractive Index Layer Composition >>
Isopropyl alcohol 510 parts by weight Water 2 parts by weight Propylene glycol monomethyl ether 227 parts by weight Methyl ethyl ketone 84 parts by weight Tetra (n) butoxytitanium 39 parts by weight KBM503 (γ-methacryloxypropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.) 6 parts by weight Dianal BR102 (acrylic resin, manufactured by Mitsubishi Rayon Co., Ltd.) 5% propylene glycol monomethyl ether solution 31 parts by mass KF-96-1000CS (silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.)
1.5% by weight of 10% methyl ethyl ketone solution.

<High refractive index layer>
Subsequently, the following high refractive index layer composition was applied onto the middle refractive index layer formed on the cellulose ester film by an extrusion coater at the second application part so that the dry film thickness was 60 nm. After drying at 80 ° C. in the drying section, further drying at 120 ° C., cooling after completion of drying, irradiating with ultraviolet light at 175 mJ / cm ² using an ultraviolet irradiation device of a high-pressure mercury lamp (80 W), A refractive index layer was formed. The reflectance is measured with a measurement means prepared from the high refractive index layer side of a cellulose ester film having a medium refractive index layer / high refractive index layer, and each measurement value is input to the control means, and the preset set value and According to the result, the supply amount to the extrusion coater of the coating solution for the high refractive index layer is controlled by controlling the number of revolutions of the liquid feed pump, and the coating amount is corrected to apply the coating. It was. The measurement of the high refractive index layer by the measuring means was performed once per second. The coating speed was 20 m / min.

<< High refractive index layer composition >>
Isopropyl alcohol 445 parts by weight Water 1.5 parts by weight Propylene glycol monomethyl ether 223 parts by weight Methyl ethyl ketone 73 parts by weight Tetra (n) butoxytitanium 545 parts by weight KBM503 0.8 parts by weight KF-96-1000CS 10% methyl ethyl ketone solution
1.4 parts by mass.
<Low refractive index layer>
Subsequently, on the high refractive index layer of the cellulose ester film having the middle refractive index layer / high refractive index layer laminate, the following low refractive index is set so that the dry film thickness becomes 120 nm by an extrusion coater in the third coating part. The layer composition was applied, dried at 80 ° C. in the third drying section, further dried at 120 ° C., cooled after completion of drying, and irradiated with ultraviolet rays using an ultraviolet irradiation device of a high-pressure mercury lamp (80 W). Irradiation was performed at 175 mJ / cm ² to form a low refractive index layer. The reflectance is measured by the measuring means prepared from the low refractive index layer side of the cellulose ester film having the middle refractive index layer / high refractive index layer / low refractive index layer, and each measured value is input to the control means and input in advance. Calculate the difference from the set value, and control the supply amount by controlling the number of revolutions of the feed pump by controlling the supply amount of the coating liquid for the high refractive index layer to the extrusion coater according to the result. Corrected and applied. The measurement of the high refractive index layer by the measuring means was performed once per second. The coating speed was 20 m / min.

<< Low refractive index layer composition >>
Propylene glycol monomethyl ether 303 parts by mass Isopropyl alcohol 305 parts by mass Tetraethoxysilane hydrolyzate A 139 parts by mass KBM503 1.6 parts by mass FZ-2207 (Nihon Unicar Company Limited) 10% propylene glycol monomethyl ether solution 1.3 parts by mass.

<< Preparation of Tetraethoxysilane Hydrolyzate A >>
580 g of tetraethoxysilane and 1144 g of ethanol are mixed, and after adding an aqueous citric acid solution (5.4 g of citric acid monohydrate dissolved in 272 g of water), the mixture is stirred at room temperature (25 ° C.) for 1 hour. Thus, tetraethoxysilane hydrolyzate A was prepared.

(Evaluation)
Each obtained sample No. Table 2 shows the results of evaluation of film thickness stability on 101 to 105. Film thickness stability was measured by the following method and evaluated according to the following evaluation rank.

Film thickness stability The film thickness was measured every 10 m from the start of application, and the variation width (R) and deviation (D) were calculated every 500 m. For the film thickness measurement, RE3000 type manufactured by Otsuka Electronics Co., Ltd. was used.

Evaluation Rank A: Variation width (R) is less than 1 nm, Deviation (D) is 0.2 nm or less ○: Variation width (R) is 1 nm or more to less than 2 nm, Deviation (D) is 0.2 nm or more to less than 0.5 nm Δ: Variation width (R) is 2 nm to less than 5 nm, Deviation (D) is 0.5 nm to less than 1.0 nm X: Variation width (R) is 5 nm to less than 10 nm, Deviation (D) is 1.0 nm Above-less than 3.0nm

  Sample No. No. 105 had a stable film thickness of 500 to 1000 m, but after 1000 m, the film thickness became unstable and it was difficult to produce a product. Sample No. In any of 101 to 104, it was confirmed that the film thickness was stable from the start of application to the end of application, and the effectiveness of the present invention was confirmed.

It is a schematic sectional drawing which shows an example of an antireflection film. It is a schematic diagram which shows an example of the manufacturing method of an antireflection film. It is a schematic block diagram which shows the relationship between the application part which comprises the antireflection film manufacturing process shown by FIG. 1, and a control part. FIG. 3 is a schematic diagram of a method of measuring a reference plate that is fixed by rotating the measurement means during calibration in the measurement means shown in FIG. 2. It is the schematic of the optical system of the sensor part shown in FIG. FIG. 3 is a schematic diagram of a method of measuring a reference plate installed so as to be rotatable by the measurement unit shown in FIG. 2 when the calibration unit moves during calibration. FIG. 3 is a schematic diagram of a method in which the measuring means shown in FIG. 2 fixed during calibration measures the reference plate through a mirror.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a-1d Antireflection film 101 Transparent film base | substrate 102 High refractive index layer 103 Low refractive index layer 104 Hard coat layer 105 Medium refractive index layer 2 Antireflection film manufacturing apparatus 3 Film base supply part 4 Coating liquid supply part 5 Coating part 501 1st 1 coating unit 502 second coating unit 503 third coating unit 501a, 502a, 503a coater 6 drying unit 601 first drying unit 602 second drying unit 603 third drying unit 7 control unit 701 first control unit 701a, 702a, 703a Measuring unit 701a1, 701a11 to 701a13 Sensor unit 701a2 Light source 701a3 Detector 701a5, 701a6, 701d1, 701d2 Reference plate 701d Reference plate mounting plate 701b, 702b, 703b Control unit 701e Mirror 702 Second control unit 703 Take-up unit 9 joint detection machine

Claims (12)

After coating or drying at least one antireflection layer coating solution directly or via another layer on the film substrate that is continuously transferred, the antireflection layer is formed. In the method of manufacturing an antireflection film, which is measured by a measuring means, compared with a reference value prepared in advance, calculated, and the result is fed back to the coating film thickness control system and manufactured while controlling the coating conditions of the antireflection layer.
The film thickness of the antireflection layer at the start of application / drying of the coating solution for the antireflection layer is measured by the measuring means calibrated in advance,
Thereafter, without stopping the process during the application of the coating solution for the antireflection layer, the measurement means is calibrated (corrected),
Measure the film thickness of the antireflection layer by the calibrated measuring means,
A method for producing an antireflection film, wherein the coating liquid for the antireflection layer is continuously applied and dried. The method for producing an antireflection film according to claim 1, wherein the measuring means is a reflectance spectroscopy measurement apparatus. The method for producing an antireflection film according to claim 1 or 2, wherein the measuring means is arranged in the width direction of the film substrate in accordance with the measurement location. The method for producing an antireflection film according to any one of claims 1 to 3, wherein the calibration of the measuring means is performed immediately after the joint of the film base is detected while the coating is continued. The method for manufacturing an antireflection film according to any one of claims 1 to 3, wherein the calibration of the measuring means is performed at least once during 5 to 180 minutes while the coating is continued. The calibration of the measuring means is performed immediately after detecting the joint of the film base material during continuation of the coating, and is performed at least once in 5 to 180 minutes. The manufacturing method of the antireflection film as described in claim | item. 7. The calibration of the measurement means includes fixing a baseline reference plate and at least one antireflection layer reference plate, and driving the measurement means to set a baseline. The manufacturing method of the antireflection film of any one of these. 7. The calibration of the measurement means includes setting the baseline by fixing the measurement means and moving the baseline reference plate and at least one antireflection layer reference plate. The manufacturing method of the antireflection film of any one of these. The calibration of the measuring means is performed by irradiating light to the baseline reference plate and at least one antireflection layer reference plate via a mirror, and reflecting from the baseline reference plate and the antireflection layer reference plate. The method for producing an antireflection film according to any one of claims 1 to 6, wherein light is read through the mirror and a baseline is set. The method for producing an antireflection film according to any one of claims 1 to 9, wherein the film thickness measurement is performed at least at three places in the width direction of the antireflection layer. The method for producing an antireflection film according to any one of claims 1 to 10, wherein the measuring means is installed on a frame that moves in the width direction of the antireflection layer. An antireflection film produced by the method for producing an antireflection film according to any one of claims 1 to 11.

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