JP2017164689A - Application device and application method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an application device with a simple mechanism, which can improve uniformity in thickness of a coating.SOLUTION: The application device comprises: a slot die; a backup roller; a coating solution supply section; a section for measuring the state of the backup roller; and a temperature controller. The coating solution supply section supplies coating solution to the slot die. The slot die supplies the coating solution to a sheet-like substrate. The backup roller supports the substrate so that the size of a gap between the substrate and the slot die is within a predetermined range, causing the substrate to travel. The section for measuring the state of the backup roller measures the state of the backup roller, the state comprising, for example, the size, and the temperature. The temperature controller controls the temperature of the coating solution supply section. This control is performed so as to reduce a difference between a predetermined reference state and a measured state of the backup roller, the measured state being measured by the section for measuring the state of the backup roller.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a coating apparatus and a coating method.

  Die coating is known as a coating method for forming a coating film having a uniform thickness. In die coating, a coating film having a uniform thickness is formed by supplying a coating liquid at a constant flow rate to a long substrate (web) that travels. Of these, in the slot die method, a slot die having a slit corresponding to the coating width and a backup roll for supporting and running the web are used as the coating head.

  In order to ensure uniformity with the slot die method, the processing accuracy of the slot die is important first, but in addition to this, technology is required to maintain a constant gap (coating gap) between the slot die and the web surface. Become. Therefore, it is generally performed to adjust the interval between the backup roll and the slot die with high accuracy when starting the application. However, no matter how accurately the adjustment is performed at the start of the work, the coating gap may change during the execution of the application. One of the factors is the deformation of the backup roll due to temperature changes. The backup roll is often made of metal, and its volume expands and contracts due to temperature changes. Such expansion and contraction changes the coating gap, and as a result, the uniformity of the coating film thickness is deteriorated.

  A technique for solving this problem is disclosed in Patent Document 1, for example. In this technique, the distance between the base material and the nozzle is kept constant by detecting the displacement in the thickness direction of the base material and moving the nozzle accordingly. Patent Document 2 discloses a technique for keeping the temperature of the backup roller constant. In Patent Document 2, as a method for executing temperature control, a method of passing a heat medium through a rotating shaft of a backup roller and a method of providing an induction heating coil inside the backup roller are shown.

JP 2005-246274 A JP 2003-93949 A

  However, the technique of Patent Document 1 has a problem that a mechanism for moving the slot die becomes large. The slot die is made thick due to the property that requires stability. For this reason, a large driving force is required to move the position of the slot die in real time. Further, making the slot die movable is not preferable in terms of reducing stability.

  Further, the technique of Patent Document 2 has a problem that the configuration of the apparatus becomes complicated because the temperature control unit mechanism is added to the backup roller.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a simple-mechanism coating apparatus capable of obtaining a coating film having high thickness uniformity.

  In order to solve the above problems, the coating apparatus of the present invention includes a slot die, a backup roller, a coating liquid supply unit, a backup roller state measurement unit, and a temperature control unit. The coating liquid supply unit supplies the coating liquid to the slot die. The slot die supplies the coating liquid to the sheet-like substrate. The backup roller supports the base material so that the gap with the slot die falls within a predetermined range, and runs the base material. The backup roller state measuring unit measures the state of the backup roller. This state is, for example, a dimension, for example, temperature. The temperature control unit controls the temperature of the coating liquid supply unit. This control is performed so as to reduce the difference between the measurement state of the backup roller measured by the backup roller state measurement unit and a predetermined reference state.

  The effect of the present invention is to provide a coating device having a simple mechanism that can provide a coating film with high thickness uniformity.

It is a block diagram which shows 1st Embodiment. It is a block diagram which shows 2nd Embodiment. It is sectional drawing which shows the backup roller and coating film of a reference | standard state. It is sectional drawing which shows the backup roller and coating film of a contracted state. It is sectional drawing which shows the backup roller and coating film of an expanded state. It is a side view which shows the example which uses a distance sensor for backup roller state measurement. It is a side view which shows another example which uses a distance sensor for backup roller state measurement. It is a side view which shows the example which uses a temperature sensor for backup roller state measurement. It is a block diagram which shows 3rd Embodiment. It is a flowchart which shows operation | movement of 3rd Embodiment. It is a flowchart which shows operation | movement of 4th Embodiment. It is a block diagram which shows 5th Embodiment. It is a flowchart which shows operation | movement of 5th Embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the preferred embodiments described below are technically preferable for carrying out the present invention, but the scope of the invention is not limited to the following. In addition, the same number is attached | subjected to the same component of each drawing, and description may be abbreviate | omitted.

(First embodiment)
FIG. 1 is a block diagram illustrating a coating apparatus according to the first embodiment. The coating apparatus includes a slot die 1, a backup roller 2, a coating liquid supply unit 3, a backup roller state measurement unit 4, and a temperature control unit 5.

  The coating liquid supply unit 3 supplies the coating liquid to the slot die 1.

  The slot die 1 supplies the coating liquid 7 to the sheet-like substrate 6.

  The backup roller 2 supports the base material 6 so that the gap with the slot die 1 is within a predetermined range, and causes the base material 6 to travel.

  The backup roller state measuring unit 4 measures the state of the backup roller 2. This state is, for example, a dimension, for example, temperature.

  The temperature control unit 5 controls the temperature of the coating liquid supply unit 3. This control is performed so as to reduce the difference between the measurement state of the backup roller 2 measured by the backup roller state measurement unit 4 and a predetermined reference state.

  With the above configuration, the state of the backup roller can be brought close to the reference state, and the uniformity of the coating film thickness can be ensured.

(Second Embodiment)
FIG. 2 is a side view showing the coating apparatus according to the second embodiment. The coating apparatus includes a slot die 10, a backup roller 20, a coating liquid supply unit 30, a backup roller state measurement unit 40, and a temperature control unit 50.

  The backup roller 20 supports the web 60 and travels in a predetermined direction.

  The slot die 10 is arranged so as to have a predetermined gap with the backup roller 20 and supplies the coating liquid to the web 60. As the web 60 travels, a coating film 70 is formed on the web 60.

  The coating liquid supply unit 30 supplies the coating liquid to the slot die 10. The coating liquid supply unit 30 includes a storage tank 31 that stores the coating liquid, a pump 32 that sends the coating liquid, and a valve 33 that controls the supply of the coating liquid to the slot die 10.

  The backup roller state measurement unit 40 measures the state of the backup roller 20. Here, the state of the backup roller is, for example, a dimension, for example, a temperature.

  The temperature control unit 50 includes a feedback control unit 51 and a temperature controller 52, and controls the temperature of the coating liquid that the coating liquid supply unit 30 supplies to the slot die 10. The control is performed so that the state of the backup roller 20 measured by the backup roller state measuring unit 40 approaches a predetermined reference state. This reference state is a state in which the gap between the slot die 10 and the backup roller 20 is appropriately adjusted, that is, a state in which the film thickness of the coating film 70 becomes a design value. The above temperature control will be described later.

  When the coating film 70 is formed on the web 60 with the above coating apparatus, the film thickness uniformity of the coating film 70 changes depending on the state of the backup roller. Examples thereof are shown in FIGS. FIG. 3A is a cross-sectional view showing that the backup roller 20 is in the reference state. At this time, as shown in FIG. 3B, the thickness of the coating film 70 is uniform. FIG. 4A is a cross-sectional view showing a state where the backup roller 20 is contracted. In the case where the backup roller 20 is made of metal, the volume contracts due to a decrease in temperature. In the coating film 70 formed in this state, as shown in FIG. 4B, the central portion becomes thicker than the design value, and the uniformity deteriorates. FIG. 5A is a cross-sectional view showing a state in which the volume of the backup roller 20 is expanded. The coating film 70 formed in this state has a thin central portion and deteriorates uniformity.

  In the present embodiment, such a state of the backup roller is grasped by the backup roller state measuring unit 40. That is, it is grasped whether the backup roller 20 is expanded or contracted as compared with the reference state, or is within a predetermined allowable range. One method is to measure the dimensions directly. For example, as shown in FIG. 6, by disposing the distance sensors 40a at the center and both ends of the backup roller 20, the dimensions of the backup roller 20 can be measured to grasp whether the backup roller 20 is in an expanded state or a contracted state. As a matter of course, the number of distance sensors 40a is not limited to three. Further, for example, only one distance sensor 40a may be used, and scanning may be performed in the width direction of the backup roller 20 as shown in FIG.

  Further, when the volume expands as the temperature rises, such as metal, and the expansion coefficient is known, information equivalent to the dimension measurement can be obtained by measuring the temperature of the backup roller 20. For example, as shown in FIG. 8, when the temperature sensor 40b measures the temperature at the center and both ends of the backup roller 20, the dimensions can be calculated from the temperature. In the following description, it is assumed that the backup roller is made of metal. In the case where the backup roller is made of a material that shrinks when the temperature rises and expands when the temperature falls, the temperature control may be reversed as described below.

  When the state of the backup roller 20 is grasped as described above, the temperature controller 50 controls the temperature of the coating liquid so that the backup roller 20 approaches the reference state using the information. Refer to FIG. 2 again. The feedback control unit 51 receives the measurement state information of the backup roller 20 from the backup roller state measurement unit 40, and controls the temperature of the coating liquid so that the state of the backup roller 20 approaches the reference state. That is, the temperature of the coating liquid is controlled to be lowered if it is expanded or higher than the reference state, and the temperature is raised if it is vice versa. The temperature controller 52 executes the temperature adjustment.

  The coating liquid whose temperature has been adjusted in this manner is sent to the slot die 10 by the coating liquid supply unit 30 and applied onto the web 60. The applied coating liquid acts to bring the temperature of the backup roller 20 close to the reference state. For this reason, the backup roller 20 is controlled so as to approach the reference state.

As described above, according to the present embodiment, the state of the backup roller is fed back, the temperature of the coating liquid is controlled, and the state of the backup roller can be brought close to the reference state by the temperature-controlled coating liquid. . For this reason, the film thickness uniformity of a coating film is securable.
(Third embodiment)
In the present embodiment, a specific configuration example and operation of the temperature control unit will be described. FIG. 9 is a block diagram showing the coating apparatus of this embodiment. Similar to the second embodiment, the coating apparatus includes a slot die 10, a backup roller 20, a coating liquid supply unit 30, a backup roller state measurement unit 40, and a temperature control unit 50. Since the configuration other than the temperature control unit is the same as that of the second embodiment, a description thereof will be omitted.

  The temperature control unit 50 includes a feedback control unit 51, a temperature controller 52a, a temperature adjustment unit 52b, and a thermometer 52c. The thermometer 52c can be installed, for example, so as to measure the temperature of the coating liquid stored in the storage tank 31, but the adjustment of the backup roller 20 is more effective when measured as close to the backup roller 20 as possible. It can be carried out. For this reason, it may be installed near the slot die 10.

  The feedback control unit 51 receives the measurement state information from the backup roller state measurement unit 40, and controls the temperature controller 52a so that the state of the backup roller 20 approaches the reference state. The temperature controller 52a controls the temperature adjusting means 52b based on the measurement result of the thermometer 52c, and the temperature adjusting means 52b executes temperature adjustment of the coating liquid. Although the temperature adjustment can be performed on the storage tank 31 as shown in FIG. 9, it may be performed on another part of the coating liquid supply unit 30 that extends from the storage tank 31 to the slot die 10.

  Next, the operation will be described. Here, the backup roller 20 is made of metal, and the size of the backup roller is measured using the distance sensor 40a as the backup roller state measurement unit.

  FIG. 10 is a flowchart showing the above operation. First, adjustment is made so that the gap between the slot die and the backup roller becomes the reference value (S1). Since this state is the reference state, the dimension of the backup roller measured at this time is set as a reference value (S2). Next, application | coating is performed and the dimension of the backup roller at that time is measured (S3). Here, when the size of the backup roller is within the predetermined standard from the reference value (S4_Yes), there is no need to change the temperature of the coating liquid. Therefore, if the coating is not completed (S5_No), the process returns to S3, Continue measuring dimensions.

  On the other hand, if the measured size of the backup roller is not within the standard (S4_No) and the measured value is larger than the reference value (S6_Yes), control is performed so that the temperature of the coating liquid is decreased by a predetermined temperature (S7). If the application is not completed (S5_No), the process returns to S3 to continue application and measurement of dimensions.

  If the measured size of the backup roller is not within the standard (S4_No) and the measured value is smaller than the reference value (S6_No), control is performed so that the temperature of the coating liquid is increased by a predetermined temperature (S8). If the application is not completed (S5_No), the process returns to S3 to continue application and measurement of dimensions.

  By performing the above operation, the size of the backup roller can be maintained within a predetermined range, and the coating film thickness uniformity can be ensured.

(Fourth embodiment)
If the volume change rate (thermal expansion coefficient) with respect to the temperature is known as described above, the temperature of the backup roller is grasped using temperature measurement instead of dimension measurement, and the coating film thickness is made uniform. It is also possible to perform control to maintain the above. Therefore, the operation will be described by taking as an example the case where the backup roller is a metal whose volume expands as the temperature rises.

  FIG. 11 is a flowchart showing the above operation. First, adjustment is made so that the gap between the slot die and the backup roller becomes the reference value (S11). Since this state is the reference state, the temperature of the backup roller measured at this time is set as a reference value (S12). Next, application | coating is performed and the temperature of the backup roller at that time is measured (S13). Here, when the temperature of the backup roller is within a predetermined standard from the reference value (S14_Yes), there is no need to change the temperature of the coating solution. Therefore, if the coating is not completed (S15_No), the process returns to S13 to Continue measuring temperature.

  On the other hand, if the measured temperature of the backup roller deviates from the standard (S14_No) and the measured value is larger than the reference value (S16_Yes), control is performed so that the temperature of the coating liquid is lowered by a predetermined temperature (S17). If the application is not completed (S15_No), the process returns to S13 to continue the application and temperature measurement.

  If the measured temperature of the backup roller is not within the standard (S14_No) and the measured value is smaller than the reference value (S16_No), control is performed so as to raise the temperature of the coating liquid by a predetermined temperature (S18). If the application is not completed (S15_No), the process returns to S13 to continue the application and measurement of the state.

  By performing the above operation, the size of the backup roller can be maintained within a predetermined range, and the coating film thickness uniformity can be ensured.

(Fifth embodiment)
In the third embodiment, the dimensions of the backup roller are measured and the temperature of the coating liquid is controlled by feeding back the measured values. However, instead of the backup roller dimensions, the quality of the coating film can be measured and fed back. It is.

  FIG. 12 is a block diagram of a coating apparatus that measures and feeds back the thickness of the coating film. The coating apparatus has a film thickness measuring device 80 that measures the film thickness of the coating film 70. Since the configuration other than the feedback of the film thickness is the same as that of the third embodiment, the description thereof is omitted.

  As described in the second embodiment, when the backup roller 20 is made of a material whose volume expands due to a temperature rise such as metal, when the temperature of the backup roller 20 is higher than a reference value, the coating film thickness becomes thin, and the temperature If it is low, it becomes thick. This phenomenon is particularly noticeable at the center in the width direction of the web 60. Therefore, the thickness of the coating film 70, particularly the central portion in the width direction, is measured. When the film thickness is thin, the temperature of the coating solution supplied to the slot die 10 is lowered, and when the film thickness is thick, the temperature is raised. It may be controlled to.

  FIG. 13 is a flowchart showing this operation. First, adjustment is made so that the gap between the slot die and the backup roller becomes the reference value (S21). In this state, test coating is executed (S22). And the film thickness of a coating film is measured and it confirms that it is a reference value (S23). If the film thickness does not reach the reference value at this stage, readjustment and test application are repeated until the film thickness reaches the reference value. Next, coating is performed, and the thickness of the coating film at that time is measured (S24). Here, when the film thickness is within the predetermined standard from the reference value (S25_Yes), there is no need to change the temperature of the coating solution. Therefore, if the coating is not completed (S26_No), the process returns to S24, and the coating and the film thickness. Continue measuring.

  On the other hand, if the film thickness deviates from the standard (S25_No) and the measured value is larger than the reference value (S27_Yes), the coating liquid is controlled to be heated by a predetermined temperature (S28). If the application is not completed (S26_No), the process returns to S24 to continue application and measurement of dimensions.

  If the measured size of the backup roller is out of the standard (S25_No) and the measured value is smaller than the reference value (S27_No), control is performed so that the temperature of the coating liquid is lowered by a predetermined temperature (S29). If the application is not completed (S26_No), the process returns to S24 to continue application and measurement of dimensions.

  By setting it as the above operation | movement, the film thickness of a coating film can be maintained in the predetermined range, and the film thickness uniformity of a coating film can be ensured.

  A program for causing a computer to execute the processes of the first to fifth embodiments described above and a recording medium storing the program are also included in the scope of the present invention. As the recording medium, for example, a magnetic disk, a magnetic tape, an optical disk, a magneto-optical disk, a semiconductor memory, or the like can be used.

  The present invention has been described above using the above-described embodiment as an exemplary example. However, the present invention is not limited to the above embodiment. That is, the present invention can apply various modes that can be understood by those skilled in the art within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1,10 Slot die 2,20 Backup roller 3,30 Coating liquid supply part 4,40 Backup roller state measurement part 5,50 Temperature control part 6 Base material 7 Coating liquid 31 Storage tank 32 Pump 33 Valve 51 Feedback control part 52 Temperature Controller 60 Web 70 Coating film 80 Film thickness measuring instrument

Claims (10)

A slot die for supplying a coating liquid to a sheet-like substrate;
A coating solution supply unit for supplying a coating solution to the slot die;
A backup roller for supporting and running the substrate;
A backup roller state measuring unit for measuring the state of the backup roller;
A temperature adjusting unit that controls the temperature of the coating liquid supply unit so that a difference between the measured state of the backup roller measured by the backup roller state measuring unit and a predetermined reference state of the backup roller is reduced. An applicator characterized by.   The coating apparatus according to claim 1, wherein the measurement state is a measurement dimension, and the reference state is a reference dimension defined by a dimension.   The said temperature control part raises temperature, if the said measurement dimension is smaller than the said reference dimension, and reduces the temperature, if the said measurement dimension is larger than the said reference dimension, The coating device of Claim 2 characterized by the above-mentioned.   The coating apparatus according to claim 1, wherein the measurement state is a measurement temperature, and the reference state is a reference temperature defined by temperature.   The coating apparatus according to claim 4, wherein the temperature adjusting unit increases the temperature if the measured temperature is lower than the reference temperature, and decreases the temperature if the measured temperature is higher than the reference temperature.   The coating apparatus according to any one of claims 1 to 5, wherein the backup roller is made of metal. A slot die for supplying a coating liquid to a sheet-like substrate;
A coating solution supply unit for supplying a coating solution to the slot die;
A backup roller for supporting and running the substrate;
A coating solution thickness measuring unit that measures the thickness of the coating solution supplied to the substrate by the slot die;
And a temperature adjusting unit that controls the temperature of the coating solution supply unit so that a difference between the measured coating solution thickness measured by the coating solution thickness measuring unit and a predetermined reference coating solution thickness is reduced. Coating device.   The temperature adjusting unit lowers the temperature if the measured coating solution thickness is smaller than the reference coating solution thickness, and increases the temperature if the measured coating solution thickness is larger than the reference coating solution thickness. 8. The coating apparatus according to 7. Supply the coating liquid to the slot die from the coating liquid supply section that holds and supplies the coating liquid,
Supplying the coating liquid from the slot die to the sheet-like substrate;
Supporting and running the substrate by a backup roller;
Measure the state of the backup roller,
A coating method, wherein the temperature of the coating liquid supply unit is controlled based on a difference between the measured measurement state of the backup roller and a predetermined reference state of the backup roller. Supplying the coating liquid to the slot die from the coating liquid supply section for holding and supplying the coating liquid;
Supplying a coating liquid from the slot die to a sheet-like substrate;
Supporting and running the substrate by a backup roller;
Measuring the state of the backup roller;
And a step of controlling the temperature of the coating liquid supply unit based on a difference between the measured measurement state of the backup roller and a predetermined reference state of the backup roller.

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