JP2013068404A - Apparatus and method for manufacturing coated material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for manufacturing a coated material capable of suppressing small unevenness in drying by a simple structure.SOLUTION: In the apparatus configured to apply a coating solution containing an organic solvent to a band-like base material 3 under carrying and then pass it through a drying furnace 4 for drying, the drying furnace includes a carry-in drying furnace 4a having a carry-in opening through which a coating film is carried in, a carry-out drying furnace 4c having a carry-out opening through which the coating film is carried out; and at least one intermediate drying furnace 4b provided between them. Differential pressure between the inside and outside of the carry-in drying furnace is controlled to be in a range of -0.1 Pa to 0.1 Pa, and the internal pressures of the intermediate drying furnace and the carry-out drying furnace are controlled to be lower than the external pressure of the drying furnace in a range of 1 Pa or less.

Description

  The present invention relates to an apparatus and a method for manufacturing a coated product. In particular, the present invention relates to an apparatus and a method for manufacturing a coated product used in the manufacture of an optical film or the like in which an organic solvent is included in a coating liquid and a film thickness unevenness with an error of 1% or less is recognized as a product defect.

  In recent years, optical film products manufactured using wet coating technology are increasingly required to have an error of 1% or less in terms of film thickness accuracy. In the production of such an optical film, an organic solvent is generally used as a solvent for the coating solution. However, the organic solvent has a higher evaporation rate than water and must be accurately dried in the drying process after coating. It is known that uneven drying such as wind ripples occurs, resulting in defects on the product.

  In particular, since the coating film contains a large amount of organic solvent in the early stages of drying, the coating fluidity is high and drying unevenness is likely to occur. A method for removing this has been proposed.

  For example, in Patent Document 1, by providing an opening for ventilation having a larger opening area than the carry-in entrance in the drying apparatus, a large amount of wind generated by the differential pressure inside and outside the dry apparatus can be obtained. From this, it is said that drying unevenness of the coating film can be reduced.

  However, since all of the wind generated by the differential pressure inside and outside the drying device cannot be passed through the ventilation port, some wind also enters from the carry-in port. Since the amount of the wind cannot be controlled, the drying device of Patent Document 1 cannot suppress slight drying unevenness.

  Also, in Patent Document 2, rollers are arranged above and below the base material entering the drying device, a minute gap is formed between the upper roller and the base material, and much of the wind generated by the differential pressure inside and outside the drying device. If it passes through the air passage provided on the upper roller, the coating film on the substrate is not disturbed by the airflow.

  However, since the air after passing through the air passage enters the drying device, the airflow in the drying device is disturbed, and the coating film on the substrate in the initial drying stage immediately after entering the drying device is uneven. There is a possibility that the drying wind may hit, and drying unevenness may occur.

Japanese Patent Laid-Open No. 2004-360961 JP 2007-71463 A

  An object of the present invention is to provide an apparatus and a method for manufacturing a coated product that can suppress the occurrence of slight drying unevenness with a simple structure.

The invention according to claim 1 of the present invention is a coating apparatus that applies a coating liquid containing an organic solvent to a belt-shaped substrate being transported to form a coating film, and passes the belt-shaped substrate being transported through the coating device. In an apparatus for producing a coated product having a drying device for drying a coating film,
The drying apparatus includes a top plate installed on a side of the substrate on which the coating film is formed, a bottom plate installed on a side of the substrate opposite to the side on which the coating film is formed, It has a right side plate installed on the right side in the transport direction and a side plate consisting of a left side plate installed on the left side, and includes a drying furnace that is a cylindrical shape in which each plate is joined without a gap,
The drying furnace includes a loading-side drying furnace having a carry-in port for carrying in the belt-like base material, a carry-out side drying furnace having a carry-out port for carrying out the belt-like base material, the carry-in side drying furnace, and the carry-out side drying furnace. And at least one intermediate drying furnace installed between and a connecting portion for connecting the carry-in side drying furnace, the intermediate drying furnace and the carry-out side drying furnace without gaps,
In addition, the pressure difference between the inside and outside of the carry-in side drying furnace is in the range of −0.1 Pa to 0.1 Pa, and the pressure inside the intermediate drying furnace and inside the carry-out side drying furnace is 1 Pa or less than the pressure outside the drying furnace. An apparatus for producing a coated product, comprising pressure control means for controlling the pressure in the drying furnace so as to be low in the range.

  The invention according to claim 2 of the present invention is characterized in that the pressure control means is an air supply means or an exhaust means for controlling an air supply amount into the drying furnace or an air discharge amount from the drying furnace, or its It is both, It is a manufacturing apparatus of the coating material of Claim 1 characterized by the above-mentioned.

In the invention according to claim 3 of the present invention, the drying furnace has an air supply port and an air supply means, an exhaust port and an exhaust means,
The air supply port is disposed on either the top plate, the right side plate, or the left side plate of the drying furnace, and the air supply means functions to supply air into the drying furnace through the air supply port. Have
The exhaust port is disposed on one of the bottom plate, the left side plate, or the right side plate of the drying furnace facing the air supply port, and the exhaust means draws air from the inside of the drying furnace through the exhaust port. It has a function to discharge,
The air flow generated in the drying furnace using either one or both of the air supply means and the exhaust means is caused to flow in both the top plate side gap and the bottom plate side gap of the drying furnace. An apparatus for producing a coated product according to Item 1 or Claim 2.

  In the invention according to claim 4 of the present invention, the distance L11 between the top plate and the base material, the upper side of the opening at the carry-in entrance, and the distance L1 between the base materials satisfy the relationship of L1 ≦ L11, and 5 mm It is the range of <= L11 <= 100mm, The manufacturing apparatus of the coating material in any one of Claims 1-3 characterized by the above-mentioned.

  In the invention according to claim 5 of the present invention, the distance L12 from the right end of the base material to the right side plate of the drying furnace and the distance L13 from the left end of the base material to the left side plate of the drying furnace are , L12 = L13, and a range of 5 mm ≦ L12 (= L13) ≦ 100 mm, and a distance L2 from the right end of the base material to the right side of the opening at the carry-in port, and the base An interval L3 from the left end of the material to the left side of the carry-in port satisfies a relationship of L2 = L3 and satisfies a relationship of 5 mm ≦ L2 (= L3) ≦ L12 (= L13). It is a manufacturing apparatus of the coated material in any one of claim | item 1 -4.

  The invention according to claim 6 of the present invention is installed so as to cover the base material between at least one top plate and the base material of the carry-in side drying furnace, the intermediate drying furnace, and the carry-out side drying furnace. It is a manufacturing apparatus of the coated material in any one of Claims 1-5 characterized by the above-mentioned.

  The invention according to claim 7 of the present invention is characterized in that the porous plate is a mesh plate or a punching plate having a major axis of an opening of 7 mm or less and an opening ratio of 50% or more and 80% or less. An apparatus for producing a coated product according to claim 6.

  The invention according to claim 8 of the present invention is characterized in that a length L5 of the carry-in side drying furnace in the substrate transport direction is in a range of 80 cm ≦ L5. It is a manufacturing apparatus of a coated material.

  The invention according to claim 9 of the present invention is characterized in that the coating film transport distance L6 from the coating section of the coating apparatus to the inlet of the carry-in drying furnace is in the range of L6 ≦ 40 cm. It is a manufacturing apparatus of the coated material in any one of -8.

  The invention according to claim 10 of the present invention is characterized in that the coating liquid is applied to the substrate and dried using the coated product manufacturing apparatus according to any one of claims 1 to 9. It is a manufacturing method of a coated material.

  According to the coated product manufacturing apparatus and manufacturing method of the present invention, the differential pressure inside and outside the carry-in side drying furnace is in the range of −0.1 Pa to 0.1 Pa, and the inside of the intermediate drying furnace and the inside of the carry-out side drying furnace By controlling the pressure in the drying furnace so that the pressure is lower than the pressure outside the drying furnace in the range of 1 Pa or less, it is possible to suppress the occurrence of slight drying unevenness and obtain a coated product without drying unevenness. Can do.

The schematic which looked at the manufacturing apparatus of the application thing of the present invention from the side Schematic sectional view of the drying furnace in the width direction of the substrate in the present invention The schematic which looked at the carrying-in entrance of the carrying-in side drying furnace in the present invention from the front The perspective schematic diagram of a part of the drying furnace in the present invention Schematic sectional view of the drying furnace in the width direction of the substrate in the present invention (when a perforated plate is provided) Schematic of the carry-in drying furnace according to the present invention as viewed from the front (when a perforated plate is provided)

  Hereinafter, an embodiment of the present invention (hereinafter referred to as the present embodiment) will be described with reference to FIGS.

  The present invention includes a differential pressure inside and outside the carry-in side drying furnace constituting a part of the drying furnace, and other drying furnaces excluding the carry-in side drying furnace, that is, the pressure inside the intermediate drying furnace and the inside of the carry-out side drying furnace. It is characterized by pressure control means for appropriately controlling.

  In this embodiment, the pressure control means constituting this characteristic portion is an air supply means for controlling the supply amount of air into the drying furnace, an exhaust means for controlling the discharge amount of air from the drying furnace, or The case of both means will be described.

  FIG. 1 is a schematic view of a part of an apparatus for producing a coated product according to the present invention as seen from the side. A coating film 7 (see FIG. 2) is coated on the belt-like substrate 3 in the coating unit 2. The substrate 3 on which the coating film 7 is formed is conveyed to the drying furnace 4. The drying furnace 4 includes a loading-side drying furnace 4 a having a carry-in port 5, a carry-out side drying furnace 4 c having a carry-out port 6, and an intermediate drying furnace 4 b. ing. In FIG. 1, only one intermediate drying furnace 4b is shown, but the present invention is not limited to this, and a plurality of intermediate drying furnaces 4b may be arranged in series. The belt-like base material 3 on which the coating film 7 is formed is carried into the drying furnace 4 from the carry-in entrance 5 and carried out of the drying furnace 4 from the carry-out exit 6.

  FIG. 2 is a schematic cross-sectional view in the width direction of the base material 3 in the drying furnace 4 shown in FIG. FIG. 2 is a schematic cross-sectional view common to all of the carry-in side drying furnace 4a, the intermediate drying furnace 4b, and the carry-out side drying furnace 4c. The drying furnace 4 has a cylindrical shape surrounding the base material 3 by the top plate 10, the bottom plate 11, the right side plate 12, and the left side plate 13, and the air supply port 22 installed on the side surface and the position facing the air supply port 22. An exhaust port 23 installed in the air supply unit, an air supply means (not shown) for supplying air into the drying furnace 4 through the air supply port 22, and air is discharged outside the drying furnace 4 through the exhaust port 23. It comprises exhaust means (not shown). The shapes of the air supply port 22 and the exhaust port 23 are not particularly limited, but are required to be large enough to supply and exhaust air into the drying furnace 4. Further, a porous plate may be provided so as to cover the air supply port 22 and the air exhaust port 23 for the purpose of controlling the air flow of the air supply and exhaust.

  FIG. 3 is a schematic diagram of the front of the carry-in port 5 in the direction of transporting the base material. The distance L11 between the top plate 10 and the base material 3 in FIG. 2 and the distance L1 between the upper side of the opening of the carry-in entrance 5 and the base material 3 in FIG. 3 satisfy the relationship of L1 <L11 and 5 mm ≦ L11 ≦ 100 mm. . Further, the distance L12 between the right end of the base material 3 and the right side plate 12 of the drying furnace and the distance L13 between the left end of the base material 3 and the left side plate 13 are equal, and 5 mm ≦ L12 (= L13 ) ≦ 100 mm, and the distance L3 from the right end of the substrate 3 to the right side of the opening at the carry-in entrance 5 and the distance L3 from the left end of the substrate 3 to the left side of the opening at the carry-in entrance 5 are 5 mm ≦ L2 = The relationship of L3 ≦ L12 = L13 is satisfied.

  FIG. 4 is a schematic perspective view of the drying furnace 4 and shows a connecting portion 20 between the carry-in side drying furnace 4a and the intermediate drying furnace 4b. Between adjacent drying furnaces is a cylindrical shape that surrounds the base material 3 by the top plate 10, the bottom plate 11, the right side plate 12, and the left side plate 13, and includes a guide roll 21 that supports and conveys the base material 3. The part 20 is connected without a gap.

  The first feature of the drying furnace 4 of the present invention is that the differential pressure inside and outside the carry-in side drying furnace 4a is maintained within a range of −0.1 Pa to 0.1 Pa. In the manufacturing apparatus of the present invention, the belt-like base material 3 on which the coating film 7 is formed is conveyed to the carry-in port 5 of the drying furnace 4 together with the accompanying air. Here, when the pressure difference between the inside and outside of the drying furnace 4 is large, a wind entering and exiting from the carry-in entrance 5 is generated, and this interferes with the accompanying air to cause turbulence of the air flow, thereby causing unevenness on the coating film surface. However, if the differential pressure inside and outside the carry-in drying furnace 4a is controlled within the range of −0.1 Pa to 0.1 Pa as in the present invention, there is almost no wind generated by the differential pressure, and the turbulence of the airflow does not occur.

  Next, the drying furnace 4 of the present invention is set so that the pressure in the intermediate drying furnace 4b and the discharge-side drying furnace 4c is set to be lower than the pressure outside the drying furnace 4 in a range of 1 Pa or less. It is characterized by. Therefore, in the intermediate drying furnace 4b and the carry-out side drying furnace 4c, the wind speed is higher than that in the carry-in side drying furnace 4a, and the base material 3 on which the coating film 7 that has passed through the carry-in side drying furnace 4a is formed. The drying is promoted in the intermediate drying furnace 4b and the carry-out side drying furnace 4c. In the present invention, it is preferable that the pressure in the intermediate drying furnace 4b and the carry-out side drying furnace 4c is set to be lower than the pressure outside the drying furnace 4 in a range of 0.1 Pa or more. If the pressure is less than 0.1 Pa, the effect of promoting drying in the intermediate drying furnace 4b and the carry-out side drying furnace 4c may not be sufficiently obtained.

  In the drying furnace 4 of the present invention, the distance L1 between the upper side of the opening of the carry-in entrance 5 and the base material 3 satisfies the relationship of L1 ≦ L11, and 5 mm ≦ L11 ≦ 100 mm. Air can be prevented from entering and exiting so as to cause turbulence of the air current, and a coated product having no drying unevenness can be produced. If L11 is smaller than 5 m, the organic solvent gas evaporating from the coating film 7 tends to stay between the coating film 7 and the top plate 10, which is not preferable because drying may not proceed. On the other hand, if it is larger than 100 mm, the amount of air entering from the carry-in entrance 5 increases and the airflow in the drying furnace 4 is disturbed, and the energy cost increases due to the need to increase the supply / exhaust amount of air in the drying furnace 4. A problem may occur, which is not preferable.

  The distance L12 from the right end of the base material 3 to the right side plate 12 and the distance L13 from the left end of the base material 3 to the left side plate 13 satisfy the relationship L12 = L13, and 5 mm ≦ L12 (= L13 ) ≦ 100 mm, the airflow in the drying furnace 4 becomes uniform in the width direction of the substrate 3, and the organic solvent gas evaporated from the coating film 7 can be exhausted without stagnation in the drying furnace 4. Further, the distance L2 from the right end of the base material 3 to the right side of the carry-in entrance 5 and the distance L3 from the left end of the base material 3 to the left side of the carry-in entrance 5 satisfy the relationship of 5 mm ≦ L2 = L3 ≦ L12 = L13. By satisfy | filling, the entrance / exit of the air from the carrying-in entrance 5 is suppressed. If L12 (= L13) is smaller than 5 mm, the base 3 and the right side plate 12 or the left side plate 13 may be in contact with each other. If it is larger than 100 mm, the amount of air entering from the carry-in entrance 5 increases and the inside of the drying furnace 4 is increased. This is not preferable because there is a possibility that the air flow is disturbed or that the energy cost increases due to the need to increase the air supply / exhaust amount of the air in the drying furnace 4.

  The purpose of the drying furnace 4 in the present invention is to suppress the occurrence of slight drying unevenness, so that the effect is most apparent in the initial stage of drying. Not all of the drying furnaces in the coated product manufacturing apparatus are based on the drying furnace 4 of the present invention, and it is possible to introduce the drying furnace 4 of the present invention only in the initial stage of drying. In that case, the drying furnace 4 of the present invention may be introduced as the first drying apparatus in the first half, and a known drying apparatus may be introduced as the second drying furnace in the second half.

  In the carry-in side drying furnace 4a of the present invention, the length L5 in the substrate conveyance direction is in the range of 80 cm ≦ L5. It is possible to suppress the occurrence of drying unevenness by allowing the coated product to stay in the carry-in side drying furnace 4a, which is a space where almost no wind is generated, in the initial drying stage where drying unevenness is most likely to occur. When L5 exceeds 200 cm, the size of the apparatus is increased, and problems such as unstable conveyance of the substrate 3 may occur.

  Furthermore, in this invention, the coating film conveyance distance L6 from the application part 2 to the entrance 5 of the carrying-in side drying furnace 4a is the range of L6 <= 40cm. Here, the coating film transport distance L6 indicates not the linear distance between the coating unit 2 and the carry-in port 5, but the length along the substrate 3 to be transported. Although the conveyance speed of the base material 3 is not a restriction | limiting matter, the manufacturing apparatus of the coating material which has a general speed of about 20 m / min or more and 100 m / min or less is used. If the coating film transport distance L6 is longer than 40 cm, the region where the coating film 7 is naturally dried by being exposed to the air in the room where the coating material manufacturing apparatus is installed cannot be ignored. Unevenness may occur, which is not preferable. The coating film conveyance distance L6 from the coating unit 2 to the carry-in entrance 5 of the carry-in side drying furnace 4a is preferably as short as possible in consideration of drying unevenness due to natural drying. However, considering the device configuration, the lower limit is 5 cm or more.

  A blower is generally used as an air supply means and an exhaust means as pressure control means in the drying furnace 4 in the present invention. However, the blower is not limited to the blower as long as the air supply amount and the exhaust amount can be adjusted. Absent. In addition, in the carrying-in side drying furnace 4a and the intermediate drying furnace 4b in FIG. 4, the air supply port 22 and the exhaust port 23 installed in the position facing the air supply port 22 are installed 2 each. Represents one embodiment of the present invention and is not limited thereto.

  Further, the differential pressure inside and outside the drying furnace 4 in the present invention is a pressure difference between the inside of the drying furnace 4 and the outside of the drying furnace 4 before the start of coating, and is measured by a differential pressure gauge (not shown). From the measurement result of the differential pressure, the air supply amount and the exhaust amount in the drying furnace 4 are adjusted so that the differential pressure is within a desired range. In this case, the adjustment of the air supply amount and the exhaust amount may be performed manually using an air supply unit and an exhaust unit, or may be automatically controlled as set.

  Moreover, although the application part 2 in this invention can use a gravure, a wire bar, a die | dye, etc., it is not limited to these.

Further, the drying furnace 4 of the present invention is porous so as to cover the base material 3 between at least one top plate 10 and the base material 3 of the carry-in side drying furnace 4a, the intermediate drying furnace 4b, and the carry-out side drying furnace 4c. It is preferable that the board 30 is installed.
In FIG. 5, the cross-sectional schematic of the drying furnace of the base-material width direction at the time of providing the perforated panel in this invention was shown. The schematic which looked at the carrying-in entrance of the carrying-in side drying furnace at the time of providing the porous plate in this invention in FIG. 6 from the front was shown.

  FIG. 5 is a cross-sectional schematic view of the drying furnace in the width direction of the substrate according to the present invention shown in FIG. 2, and a perforated plate 30 is further provided. FIG. A porous plate 30 is further provided in the schematic view of the carry-in port as viewed from the front. The air flow in the drying furnace 4 can be a uniform flow controlled by passing through the opening of the perforated plate 30, and can be a coated product without drying unevenness. In particular, even when the conveyance speed is improved by providing a porous plate, it is possible to efficiently suppress the occurrence of uneven drying.

  The porous plate 30 is a mesh plate or a punching plate having an opening having a major axis of 7 mm or less and an opening ratio of 50% or more and 80% or less, and an air flow generated by supply / exhaust in the drying furnace 4 is an opening of the porous plate 30. A uniform flow is controlled by passing through the section. The wind that strikes the surface of the coating film 7 applied on the substrate 3 is a uniform airflow that has passed through the perforated plate 30, so that it does not disturb the surface of the coating film 7 and suppresses the occurrence of uneven drying. it can. If the aperture ratio of the perforated plate 30 is lower than 50%, the resistance to the air flow in the drying furnace 4 is large, and there is a possibility that an air flow necessary and sufficient for exhausting the organic solvent gas evaporated from the coating film 7 cannot be obtained. Further, when the major axis of the opening is larger than 7 mm or when the opening ratio is higher than 80%, the resistance to the airflow in the drying furnace 4 is small, and it becomes difficult to control the airflow uniformly, and thus drying unevenness occurs. There is a fear. In order to make the air flow uniform, the smaller the major axis of the opening of the perforated plate, the better. However, considering the aperture ratio and the like, the major axis of the aperture of the porous plate is preferably 2 mm or more.

  The position where the perforated plate 30 is installed is not particularly limited, but if the distance between the perforated plate 30 and the substrate 3 is 15 mm or more, the air flow controlled by the perforated plate 30 is disturbed between the perforated plate 30 and the coating film 7. There is a risk. Further, if the distance between the porous plate 30 and the substrate 3 is less than 5 mm, the surface of the coating film 7 may come into contact with the porous plate 30 when the substrate is conveyed.

  The apparatus and method for producing a coated product of the present invention can be used for various products, and is particularly effective for coating a dispersion using an organic solvent as a solvent. Among them, it is effective for a product having less tolerance for drying unevenness, such as an optical film, which has been increasing in demand in recent years. Here, the optical film is a film used mainly on or on the outermost surface of a display device such as a liquid crystal display or a plasma display, and is a hard coat film, an antireflection film, an antiglare film, an optical compensation film, an optical film. Examples thereof include a diffusion film and an antistatic film.

  The coated product of the present invention includes a coating film obtained by coating and drying a coating solution on a band-shaped substrate. The thickness of the coating film after drying is preferably 2 μm or more and 20 μm or less. In the manufacturing apparatus and manufacturing method of the coated material of the present invention, it can be suitably used when a coating film having a thickness after drying of 2 μm or more and 20 μm or less is formed on a substrate. Moreover, as a coated material of this invention, it can use suitably, when apply | coating the coating liquid containing particle | grains on a base material. In the coating liquid containing particles, it is required that uneven drying is easily noticeable due to aggregation of particles, and that there is no uneven drying at a high level. By using the coating material manufacturing method and manufacturing method of the present invention, drying unevenness can be suppressed even when a coating liquid containing particles that are required to have no drying unevenness at a high level is used. In the production apparatus and production method of the present invention, it can be suitably used for an antiglare film comprising an antiglare layer obtained by applying and drying a coating liquid containing particles on a substrate.

  As the strip-shaped base material 3 used in the present invention, various materials can be used depending on applications. Examples of components constituting the substrate 3 include cellulose films such as acetyl cellulose and triacetyl cellulose, polyester films such as polyethylene terephthalate and polyethylene naphthalate, and acrylic films such as polymethyl methacrylate. It is not limited to these. Moreover, the base material 3 may consist of a single layer, or may consist of multiple layers. In addition, the thickness of the base material 3 is 10 to 100 μm.

  Moreover, in the manufacturing apparatus and manufacturing method of the coating material of this invention, you may provide apparatuses other than the application part shown here and a drying furnace. For example, when an ultraviolet curable resin or an electron beam curable resin is used as a binder in the coating solution, an ultraviolet irradiation device and an electron beam irradiation device are provided, respectively. Further, when a thermosetting resin is used as a binder in the coating solution, a heating device can be provided.

  An embodiment of the present invention will be described with reference to the drawings.

Example 1
Silica particles having an average particle size of 3.0 μm are 4.2 wt%, pentaerythritol triacrylate (manufactured by Kyoeisha Chemical Co., Ltd.) 36.0 wt% as a binder, and Irgacure 184 (manufactured by Ciba Specialty Chemicals) 1.8 wt% as a photopolymerization initiator. %, 34.8 wt% toluene as a solvent and 23.2 wt% dioxolane were prepared as a coating solution. The viscosity of the prepared coating solution was 3.0 mPas.

  Next, a triacetyl cellulose (TAC) substrate having a width of 1340 mm and a thickness of 80 μm is used as the belt-like substrate 3 that is continuously conveyed, and is prevented by a coating process, a drying process, a second drying process, and an ultraviolet irradiation process. A dazzling film was prepared. In addition, the conveyance speed at this time is 40 m / min.

  In the coating step, a coating solution was applied using a coating apparatus equipped with an extrusion type die head. The thickness of the coating film 7 was 15 μm so that the film thickness after drying was 5 μm.

  Next, in the drying process, a drying furnace 4 having a total length of 10 m having eight intermediate drying furnaces 4b and having a connecting portion 20 provided with a guide roll 21 between the respective drying furnaces was used. The right side plate 12 and the left side plate 13 of each drying furnace are provided with one air supply port 22 and one exhaust port 23, respectively. Further, the distance L1 between the top plate 10 and the base material 3 is 20 mm, the distance L11 between the upper side of the opening of the carry-in entrance 5 and the base material 3 is 6 mm, the distance L12 between the right end of the base material 3 and the right side plate 12, and the base The distance L13 between the left end of the material 3 and the left side plate 13 is 50 mm, the distance L2 between the right end of the base material 3 and the opening right side of the carry-in entrance 5, and the left end of the base material 3 and the open left side of the carry-in entrance 5 L3 is 20 mm. The length L5 of the carry-in side drying furnace 4a is 100 cm, and the coating film transport distance L6 is 25 cm.

  As the pressure control means in the drying furnace 4, an air supply means and an exhaust means using a blower are used, the differential pressure inside and outside the carry-in side drying furnace 4 a is in the range of −0.1 Pa to 0.1 Pa, and intermediate drying The rotation speed of the blower was manually controlled so that the pressure in the furnace 4b and the discharge-side drying furnace 4b was 0.6 Pa lower than the pressure outside the drying furnace 4.

  As a second drying furnace (not shown), a drying device having a length of 5 m that blows hot air from a slit nozzle is used. Finally, an ultraviolet irradiation device (not shown) of an ultra-high pressure mercury lamp is used as an ultraviolet irradiation process. Using.

  Since the transport speed is 40 m / min and the coating film transport distance L6 is 25 cm, the time required for the coating film 7 applied to the substrate 3 in the coating unit 2 to reach the carry-in port 5 is about 0.4 seconds. The coating film 7 was naturally dried during that time, and there was no occurrence of uneven drying.

  Since there is almost no wind in the carry-in side drying furnace 4a, the coating film 7 is transferred to the intermediate drying furnace 4b without being rapidly dried. Since the pressure in the intermediate drying furnace 4b is 0.6 Pa lower than the outside of the drying furnace 4 and the air in the drying furnace 4 is exhausted by the exhaust means, the organic solvent gas evaporated from the coating film 7 is exhausted from the exhaust port 23. , Drying is promoted. However, since the coating film 7 is not completely dried only by passing through the intermediate drying furnace 4b and the carry-out side drying furnace 4c, the drying was completed by the hot air of the second drying furnace.

  As described above, an antiglare film (applied product) having an antiglare layer as a coating film on a substrate was obtained. The obtained antiglare film was cut out in the width direction, and in the room where the fluorescent lamp was lit, the presence or absence of drying unevenness was determined while the fluorescent lamp was sequentially reflected in the width direction on the surface of the antiglare layer. In Example 1, the coating film 7 is gently and precisely dried at the initial stage of drying in the intermediate drying furnace 4b and the unloading side drying furnace 4c, the organic solvent component in the coating film 7 is reduced, and the fluidity is reduced. Is reduced, that is, it is difficult for uneven drying to occur. In order to reach the second drying furnace in this state, it was confirmed that no drying unevenness occurred even when the coating film 7 was rapidly dried with hot air.

(Example 2)
A coating solution identical to the coating solution described in Example 1 was prepared.

  Next, as the strip-shaped base material 3 that is continuously conveyed, a triacetyl cellulose (TAC) base material having a width of 1340 mm and a thickness of 80 μm as in Example 1 is used, and a coating process, a drying process, and a second drying process. An antiglare film was produced by the process and the ultraviolet irradiation process. In addition, the conveyance speed at this time is 50 m / min.

  In the coating step, a coating solution was applied using a coating apparatus equipped with an extrusion type die head. The thickness of the coating film 7 was 15 μm so that the film thickness after drying was 5 μm.

  Next, in the drying process, a drying furnace 4 having a total length of 10 m having eight intermediate drying furnaces 4b and having a connecting portion 20 provided with a guide roll 21 between the respective drying furnaces was used. The right side plate 12 and the left side plate 13 of each drying furnace are provided with one air supply port 22 and one exhaust port 23, respectively. The air supply port 22 and the exhaust port 23 are covered with a punching plate (not shown) in which a circular hole having a diameter of 5 mm is processed with an opening ratio of 60%. Further, the distance L11 between the top plate 10 and the base material 3 is 20 mm, the distance L1 between the upper side of the opening of the carry-in entrance 5 and the base material 3 is 6 mm, the distance L12 between the right end of the base material 3 and the right side plate 12, and the base The distance L13 between the left end of the material 3 and the left side plate 13 is 50 mm, the distance L2 between the right end of the base material 3 and the opening right side of the carry-in entrance 5, and the left end of the base material 3 and the open left side of the carry-in entrance 5 L3 is 20 mm. The length L5 of the carry-in side drying furnace 4a is 100 cm, and the coating film transport distance L6 is 25 cm.

  Furthermore, the porous plate 30 was installed between the top plate 10 and the base material 3 in all the drying furnaces of the carry-in side drying furnace 4a, the intermediate drying furnace 4b, and the carry-out side drying furnace 4c. The perforated plate 30 is made of stainless steel having a thickness of 2 mm, and circular holes having a diameter of 5 mm are processed with an opening ratio of 60%. The interval between the perforated plate 30 and the substrate 3 was 10 mm.

  As the pressure control means in the drying furnace 4, an air supply means and an exhaust means using a blower are used, the differential pressure inside and outside the carry-in side drying furnace 4 a is in the range of −0.1 Pa to 0.1 Pa, and intermediate drying The rotation speed of the blower was manually controlled so that the pressure in the furnace 4b and the discharge-side drying furnace 4b was 0.6 Pa lower than the pressure outside the drying furnace 4.

  As a second drying furnace (not shown), a drying device having a length of 5 m that blows hot air from a slit nozzle is used. Finally, an ultraviolet irradiation device (not shown) of an ultra-high pressure mercury lamp is used as an ultraviolet irradiation process. Using. The coating film transport distance L6 was 25 cm.

  Since there is almost no wind in the carry-in side drying furnace 4a, the coating film 7 is transferred to the intermediate drying furnace 4b without being rapidly dried. Since the pressure in the intermediate drying furnace 4b is 0.6 Pa lower than the outside of the drying furnace 4 and the air in the drying furnace 4 is exhausted by the exhaust means, the organic solvent gas evaporated from the coating film 7 is exhausted from the exhaust port 23. , Drying is promoted. Here, since the porous plate 30 is installed in the drying furnace 4, the air flow by the supply and exhaust air is rectified through the porous plate 30. For this reason, turbulent flow does not occur on the surface of the coating film 7 and drying unevenness does not occur on the surface of the coating film 7.

  Since the coating film 7 was not completely dried only by passing through the intermediate drying furnace 4b and the carry-out side drying furnace 4c, the drying was completed by the hot air of the second drying furnace. As described above, an antiglare film (applied product) having an antiglare layer as a coating film on a substrate was obtained. The obtained antiglare film was cut out in the width direction, and in the room where the fluorescent lamp was lit, the presence or absence of drying unevenness was judged while sequentially reflecting the fluorescent lamp on the surface of the antiglare layer. In (Example 2), the coating film 7 is gently and precisely dried at the initial stage of drying in the intermediate drying furnace 4b and the carry-out side drying furnace 4c, the organic solvent component in the coating film 7 is reduced, and the fluidity is reduced. Is reduced, that is, it is difficult for uneven drying to occur. In order to reach the second drying furnace in this state, it was confirmed that no drying unevenness occurred even when the coating film 7 was rapidly dried with hot air. Moreover, in (Example 2), since the perforated plate was used, an antiglare film (applied product) having no drying unevenness could be obtained even when the conveyance speed was increased as compared with (Example 1).

(Comparative example)
A coating solution identical to the coating solution described in Example 1 was prepared.

  Next, as the strip-shaped base material 3 that is continuously conveyed, a triacetyl cellulose (TAC) base material having a width of 1340 mm and a thickness of 80 μm as in Example 1 is used, and a coating process, a drying process, and a second drying process. An antiglare film was produced by the process and the ultraviolet irradiation process. In addition, the conveyance speed at this time is 40 m / min.

  In the coating step, a coating solution was applied using a coating apparatus equipped with an extrusion type die head. The thickness of the coating film 7 was 15 μm so that the film thickness after drying was 5 μm.

  Next, in the drying process, a drying furnace 4 having a total length of 10 m having eight intermediate drying furnaces 4b and having a connecting portion 20 provided with a guide roll 21 between the respective drying furnaces was used. The right side plate 12 and the left side plate 13 of each drying furnace are provided with one air supply port 22 and one exhaust port 23, respectively. The air supply port 22 and the exhaust port 23 are covered with a punching plate (not shown) in which a circular hole having a diameter of 5 mm is processed with an opening ratio of 60%. Further, the distance L11 between the top plate 10 and the base material 3 is 20 mm, the distance L1 between the upper side of the opening of the carry-in entrance 5 and the base material 3 is 6 mm, the distance L12 between the right end of the base material 3 and the right side plate 12, and the base The distance L13 between the left end of the material 3 and the left side plate 13 is 50 mm, the distance L2 between the right end of the base material 3 and the opening right side of the carry-in entrance 5, and the left end of the base material 3 and the open left side of the carry-in entrance 5 L3 is 20 mm. The length L5 of the carry-in side drying furnace 4a is 100 cm, and the coating film transport distance L6 is 25 cm. In (Comparative Example 1), the pressure control means in the drying furnace 4 was not operated.

  As a second drying furnace (not shown), a drying device having a length of 5 m that blows hot air from a slit nozzle is used. Finally, an ultraviolet irradiation device (not shown) of an ultra-high pressure mercury lamp is used as an ultraviolet irradiation process. Using. The coating film transport distance L6 was 25 cm.

  Since the coating film 7 was not completely dried only by passing through the intermediate drying furnace 4b and the carry-out side drying furnace 4c, the drying was completed by the hot air of the second drying furnace. As described above, an antiglare film (applied product) having an antiglare layer as a coating film on a substrate was obtained. The obtained antiglare film was cut out in the width direction, and in the room where the fluorescent lamp was lit, the presence or absence of drying unevenness was judged while sequentially reflecting the fluorescent lamp on the surface of the antiglare layer. In the anti-glare film of (Comparative Example 1), it was confirmed that the reflected state of the fluorescent lamp was different in the width direction, and the reflected image of the fluorescent lamp projected on the base material was different in the width direction. In the anti-glare film of (Comparative Example 1), streaky drying unevenness extending in the direction of conveyance of the substrate (the direction perpendicular to the width direction) was confirmed.

  Therefore, the anti-glare film could be produced without causing slight drying unevenness in the production apparatus and production method of the coated product in (Example 1) and (Example 2).

  The apparatus and method for producing a coated product of the present invention can be widely used for coating a dispersion using an organic solvent as a solvent, and among them, drying unevenness more than ever, such as an optical film whose demand has been increasing in recent years. It is effective for products with a small tolerance.

DESCRIPTION OF SYMBOLS 1 Manufacturing apparatus 2 Application | coating part 3 Base material 4 Drying furnace 4a Carry-in side drying furnace 4b Intermediate drying furnace 4c Carrying-out side drying furnace 5 Carry-in port 6 Carry-out port 7 Coating film 10 Top plate 11 Bottom plate 12 Right side plate 13 Left side plate 20 Connecting portion 21 Guide roll 22 Air supply port 23 Exhaust port 30 Perforated plate L1 Spacing of upper side of base material and carry-in port Top plate and base plate L11 Spacing of base material and top plate L2 Base material end and carry-in port opening Distance L3 on the right side Distance L12 between the substrate end and the left side of the opening of the carry-in entrance L12 Distance between the substrate end and the right side plate L13 Distance between the substrate end and the left side plate L5 Loading side drying furnace length L6 Coating film conveyance distance

Claims (10)

Coating having a coating apparatus that forms a coating film by applying a coating solution containing an organic solvent to a belt-shaped substrate being transported, and a drying device that dries the coating film by passing the belt-shaped substrate being transported In manufacturing equipment,
The drying apparatus includes a top plate installed on a side of the substrate on which the coating film is formed, a bottom plate installed on a side of the substrate opposite to the side on which the coating film is formed, It has a right side plate installed on the right side in the transport direction and a side plate consisting of a left side plate installed on the left side, and includes a drying furnace that is a cylinder in which each plate is joined without a gap,
The drying furnace includes a loading-side drying furnace having a carry-in port for carrying in the belt-like base material, a carry-out side drying furnace having a carry-out port for carrying out the belt-like base material, the carry-in side drying furnace, and the carry-out side drying furnace. And at least one intermediate drying furnace installed between and a connection part for connecting the carry-in side drying furnace, the intermediate drying furnace and the carry-out side drying furnace without gaps, and
The differential pressure inside and outside the carry-in side drying furnace is in the range of −0.1 Pa to 0.1 Pa, and the pressure inside the intermediate drying furnace and inside the carry-out side drying furnace is 1 Pa or less than the pressure outside the drying furnace. And a pressure control means for controlling the pressure in the drying furnace so as to be low.   2. The pressure control means is an air supply means and / or an exhaust means for controlling an air supply amount into the drying furnace and / or an air discharge amount from the drying furnace, or both. The manufacturing apparatus of the described coated material. The drying furnace has an air supply port and an air supply unit, an exhaust port and an exhaust unit,
The air supply port is disposed on either the top plate, the right side plate, or the left side plate of the drying furnace, and the air supply means functions to supply air into the drying furnace through the air supply port. Have
The exhaust port is disposed on one of the bottom plate, the left side plate, or the right side plate of the drying furnace facing the air supply port, and the exhaust means draws air from the inside of the drying furnace through the exhaust port. It has a function to discharge,
The air flow generated in the drying furnace using either one or both of the air supply means and the exhaust means is caused to flow in both the top plate side gap and the bottom plate side gap of the drying furnace. The manufacturing apparatus of the coated material of Claim 1 or Claim 2.   The distance L11 between the top plate and the base material, the upper side of the opening at the carry-in entrance, and the distance L1 between the base materials satisfy the relationship of L1 ≦ L11 and are in the range of 5 mm ≦ L11 ≦ 100 mm. The manufacturing apparatus of the coated material in any one of Claims 1-3.   An interval L12 from the right end of the substrate to the right side plate of the drying furnace and an interval L13 from the left end of the substrate to the left side plate of the drying oven satisfy the relationship L12 = L13, and 5 mm ≦ L12 (= L13) ≦ 100 mm, and the distance L2 from the right end of the substrate to the right side of the opening at the carry-in port, and the left side of the carry-in port from the left end of the substrate 5. The coating according to claim 1, wherein the distance L3 satisfies the relationship of L2 = L3 and satisfies the relationship of 5 mm ≦ L2 (= L3) ≦ L12 (= L13). Manufacturing equipment.   A porous plate installed so as to cover the base material is provided between at least one top plate and the base material of the carry-in side drying furnace, the intermediate drying furnace, and the carry-out side drying furnace. The manufacturing apparatus of the coating material in any one of Claims 1-5.   The said perforated board is a mesh board or punching board whose opening part has a major axis of 7 mm or less, and an opening rate is 50% or more and 80% or less, The manufacture of the coating material of Claim 6 characterized by the above-mentioned. apparatus.   The length L5 of the said carrying-in side drying furnace of a base material conveyance direction exists in the range of 80 cm <= L5, The manufacturing apparatus of the coated material in any one of Claims 1-7 characterized by the above-mentioned.   The coating film transport distance L6 from the coating unit of the coating apparatus to the carry-in port of the carry-in side drying furnace is in the range of L6 ≦ 40 cm. manufacturing device.   A method for producing a coated product, wherein the coating solution is applied to the substrate and dried using the device for producing a coated product according to any one of claims 1 to 9.