JP2017094233A - Intermittent coating device and intermittent coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intermittent coating device and an intermittent coating method capable of surely forming a coating film having almost no variation in thickness and having an extremely uniform thickness, without coating nonuniformity, by enabling a linear mobile device of using a linear motor to intermittently carry a web material at an extremely uniform moving speed, by imparting always constant tension to the web material without a time variation.SOLUTION: An intermittent coating device comprises a rolling-out device for rolling out a roll-like web material, tension imparting means for imparting tension by suspending a dancer roll by the rolled-out web material, a back-up roll for supporting by winding the web material, a linear mobile device for carrying the web material by an intermittent moving quantity, a resting-holding device for holding the whole width by resting the web material, a coater for discharging a coating liquid on the web material, and a coating liquid supply device for supplying the coating liquid to the coater.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an intermittent coating apparatus and an intermittent coating method that can stably and intermittently form a coating film having a uniform thickness on a web material that is a continuous sheet-shaped member.

  A technique for intermittently forming a coating film having a uniform thickness at a predetermined interval on a web material such as a plastic film or paper has become indispensable for manufacturing an electrode of an electric storage device, an LED phosphor sheet, or the like. . Actually, as an intermittent coating apparatus that intermittently forms a coating film with an applicator, there is a coating apparatus using a slit nozzle in the applicator (for example, Patent Document 1). This coating device intermittently applies a coating film of uniform thickness by intermittently discharging the coating liquid from the elongated discharge port of the slit nozzle onto the web material that is stably supported by the backup roll and moves at a constant speed. Can be formed.

  Furthermore, while the slit nozzle is moved intermittently with a linear moving device that uses a linear motor capable of high-accuracy speed control, the coating liquid is discharged from the slit nozzle onto the web material that is stationary and fixed on the stage. In some cases, a uniform thickness coating film can be formed intermittently (for example, Patent Document 2).

  In the coating apparatus of Patent Document 2, since the slit nozzle is moved using a linear motor having a much higher speed uniformity than the rotary motor used in the coating apparatus of Patent Document 1, a more uniform thickness is obtained. It should be possible to intermittently form a coating film. However, in actual application, even in a clean environment, when the web material is brought into contact with the plane of the stage, particles of micron order are sandwiched between the two. When the web material is adsorbed and fixed to the stage in this state, a small uneven deformation occurs in a part of the web material. When coating is performed with this, small unevenness in the coating film is generated from the outside as well, resulting in a coating defect, and the unevenness in the film thickness cannot be overlooked. Thus, a coating film having a uniform thickness cannot be formed. Therefore, the coating apparatus of Patent Document 2 can be applied to a hard base material such as glass whose surface is not deformed even when particles are sandwiched, but cannot be applied to a soft base material such as a web material.

  Even in the coating apparatus of Patent Document 1, particles floating in the air are similarly sandwiched between the web material and the backup roll, but at the same time, air is also involved. Therefore, an air layer having a thickness of several μm is formed between the web material and the backup roll, and micron-order particles are included in the air layer, so that the web material is not deformed. Therefore, when the coating liquid is discharged from the slit nozzle onto the web material supported by the backup roll, a coating film having a uniform thickness without coating defects such as unevenness of unevenness can be formed.

  From the above, in the coating apparatus of Patent Document 1, it is ideal that the web material is intermittently moved by a linear moving apparatus using a linear motor to form a coating film, with the most uniform thickness and uniform coating. This coating film can be formed intermittently. However, the speed of the linear motor is controlled in units of several mSec, but in such a short cycle, the tension acting on the web material serving as the load of the linear motor cannot be controlled with a normal tension control system. Therefore, the linear motor cannot move the web material at a uniform speed as compared with the rotary motor due to the influence of time variation of the tension (load). As a result, even if a linear motor is applied, it is possible to obtain the same thickness uniformity as that of a rotary motor, and if the tension does not fluctuate over time, the coating film is far inferior in thickness uniformity. It can only be formed. Therefore, in order to exert the original performance of the linear motor, it is necessary to always keep the tension acting on the web material as a load constant without changing with time.

  Further, in the coating apparatus of Patent Document 1, there is no problem when the web material is continuously moved and intermittently applied by discharging the coating liquid intermittently from the slit nozzle, but the web material is moved intermittently. That is, if the web material is repeatedly moved and stopped, and the coating liquid is ejected from the slit nozzle during application, application unevenness that is straight in the width direction may occur. In a linear movement device using a linear motor, the web material cannot be moved continuously, and the web material is always intermittently moved repeatedly and stopped. Is also preferable when a linear moving device is introduced.

JP-A-9-108605 JP 2009-45565 A

The present invention has been made in order to solve the above-described problems of the prior art, and the object of the present invention is to stably support the backup roll and apply the coating liquid from the applicator. By making it possible to always apply a constant tension to the web material on which the film is formed intermittently without time fluctuation, the linear moving device using a linear motor holds the web material downstream of the backup roll. As a result of the intermittent movement at a very uniform moving speed, the web material is intermittently conveyed at a very uniform moving speed, and as a result, a coating film having a very uniform thickness and a very uniform thickness can be ensured without uneven coating. It is in providing the intermittent coating apparatus and intermittent coating method which can be formed in this.

  The present invention also provides an intermittent operation in which a specific coating unevenness does not occur at all even when a coating film is formed by applying a coating liquid from a coating device to a web material that is intermittently moved and stopped repeatedly by a linear moving device. It is also an object of the present invention to provide a coating apparatus and an intermittent coating method.

  The object of the present invention is achieved by the means described below.

  The intermittent coating apparatus of the present invention is an intermittent coating apparatus that intermittently moves a web material to form a coating film intermittently, and unwinds the web material in a roll form by intermittently moving it by an intermittent movement amount. An apparatus, a web material tension applying means for applying tension to the web material by suspending a dancer roll movable in the direction of gravity on the unwound web material, and a web material to which tension is applied downstream are wound. A backup roll that is attached and supported, a linear movement device that moves the web material linearly while holding the full width of the web material on the downstream side of the backup roll, and conveys the web material by an intermittent movement amount; and a web material on the downstream side of the linear movement device. A stationary holding device that holds the entire width in a stationary manner, an applicator having a discharge port for discharging the coating liquid onto the web material supported by the backup roll, and supplying the coating liquid to the applicator Characterized in that it and a coating liquid supply apparatus. Here, it is preferable that the material of all the roll surfaces that the web material contacts before reaching the backup roll from the unwinding device is a synthetic resin or a synthetic rubber.

  The intermittent coating method of the present invention is an intermittent coating method in which a coating liquid is applied to a web material that moves intermittently using the above intermittent coating device, and the web material is kept constant while maintaining the full width by the linear moving device. By moving the dancer roll on which the web material is suspended in a straight line by the intermittent movement amount at speed, the web material to which constant tension is constantly applied by the suspended dancer roll is backed up. The coating liquid supplied from the coating liquid supply device is discharged from the applicator at a position supported by a roll, and the coating liquid is applied onto the web material.

  By using the intermittent coating apparatus and the intermittent coating method of the present invention, the dancer roll suspended from the web material can always apply a constant tension to the web material without time variation. Since the load on the linear moving device that maintains the full width is also always constant, the linear moving device can hold the web material at the full width downstream of the backup roll and intermittently move at a very uniform moving speed. As a result, the web material is intermittently conveyed at a very uniform moving speed. The coating solution is applied to the web material that is stably supported by the backup roll and moves at an extremely uniform speed in this way, so the coating thickness is very small and the coating thickness is extremely uniform. A film can be reliably formed, and a coating film having no coating unevenness such as uneven unevenness can be formed intermittently.

  In addition, if the intermittent coating apparatus and the intermittent coating method according to the preferred embodiment of the present invention are used, the material of all roll surfaces that are in contact before reaching the backup roll from the unwinding apparatus is made of synthetic resin or synthetic rubber. The influence of the heat received from the roll when the web material is stopped can be made very small compared to a material having a high thermal conductivity such as a metal roll. As a result, even if the web material is intermittently moved for intermittent application,

It is a schematic front view of the intermittent coating apparatus which concerns on this invention. It is explanatory drawing which shows the first half of the one aspect | mode of the intermittent application method which concerns on this invention in steps. It is explanatory drawing which shows the latter half of the one aspect | mode of the intermittent application method which concerns on this invention in steps.

  The present invention will be described with reference to the drawings. FIG. 1 is a schematic front view of an intermittent coating apparatus 1 according to the present invention.

  First, referring to FIG. 1, there is shown an intermittent coating apparatus 1 of the present invention which is an intermittent coating apparatus that intermittently moves a web 10 as a web material to intermittently form a coating film. The part of the intermittent coating apparatus 1 that intermittently moves the web 10 includes an unwinder 3 that unwinds the web 10, a dancer roll unit 2 that applies tension to the unwound web 10, and a web from the dancer roll unit 2 to the backup roll 6. 10 is a linear moving device 4 for intermittently moving a web 10 that is wound around a guide roll 9 that guides 10 and a backup roll 6 that freely rotates and is guided in the horizontal direction on the downstream side of the backup 6, and a web on the downstream side of the linear moving device 4 10 is provided with a stationary holding device 5 that holds the web 10 when stationary, and a downstream conveyance unit 16 that is downstream of the stationary holding device 5 and conveys the web 10 to a downstream process such as drying. The application portion of the intermittent application apparatus 1 includes an application unit 7 that applies the application liquid 12 to the web 10 supported by the backup roll 6, and an application liquid supply unit 100 that supplies the application liquid 12 to the application unit 7. .

  Next, details of the configurations and functions of the devices and units constituting the portion of the intermittent coating apparatus 1 that intermittently moves the web 10 will be described in order from the upstream side. First, the unwinder 3 is an unwinding device that unwinds the roll-shaped web 10 intermittently by an intermittent movement amount. That is, the web 10 is unwound by a specified length indicated by the intermittent movement amount L from the unwinding shaft 31 on which the roll-shaped web 10 is mounted, and then the brake is applied to the unwinding shaft 31. Even if the web 10 is pulled from the downstream side, unwinding exceeding a specified amount is prevented. The unwinding operation of unwinding and stopping the unwinding shaft 31 is performed when the linear moving device 4 before coating is stopped.

  The dancer roll unit 2 that applies tension to the web 10 that has been unwound from the unwinder 3 has four fixed rolls 21 </ b> A that are rotatable and positionally restricted in the X direction (horizontal direction) and the Z direction (vertical direction). , B, C, D, three rotatable lifting rolls 22A, B, C, a connecting plate 23 for connecting and holding the three lifting rolls 22A, B, C, and the connecting plate 23 in the direction of gravity. A linear guide 24 that freely guides in the vertical direction (Z direction), a wire 27 whose both ends are connected to the connecting plate 23 and the weight 26, and a rotatable pulley 25 around which the wire 27 is wound. Has been. With this configuration, the three elevating rolls 22A, B, and C can be raised and lowered in the vertical direction. Therefore, when the web 10 is unwound from the unwinder 3 by one intermittent movement amount L, the lifting rolls 22A, 22B, and 22C held by the connecting plate 23 are L / 6 in the vertical direction from the initial position. Only descend. That is, the lifting rolls 22 </ b> A, B, and C that are dancer rolls are lowered by a predetermined length while being suspended from the web 10 in the direction of gravity. A tension T having a size of T = (weight of lifting rolls 22 </ b> A, B, C + weight of connecting plate 23−weight W of weight 26) / 6 is applied to web 10. That is, the dancer roll unit 2 suspends the lifting rolls 22A, 22B, and 22C, which are dancer rolls that are movable in the direction of gravity, from the web 10 unwound from the unwinder 3, and applies the tension to the web 10. It becomes a material tension | tensile_strength provision means. From the above formula, the weight 26 can be said to be tension adjusting means because the magnitude of the tension T can be freely adjusted by the weight W of the weight 26. Similarly, the weight 26 may be an air cylinder or a hydraulic cylinder in which the tensile force of the wire 27 can be freely adjusted. Moreover, it is preferable that the material of the surface (outer peripheral surface) of the fixing rolls A, B, C, and D and the lifting rolls 22A, B, and C that are in contact with the web 10 is a synthetic resin or synthetic rubber having a low thermal conductivity. Even if there is a slight temperature difference between the web 10 and the fixed rolls 21A, B, C, D and the lifting rolls 22A, B, C, if the material of the surface of each roll is the above, it will be stationary. The portion of the web 10 in contact with the surface of each roll does not change in temperature locally. There is very little if any. When the stationary web 10 comes into contact with the surface of the metal roll having a high thermal conductivity, the so-called overall heat transfer coefficient is increased, and the amount of heat transferred to the contacted portion of the web 10 increases so that the temperature is locally increased. The temperature changes in the moving direction (X direction) of the web 10. When the coating is applied to the web 10 having such local temperature unevenness, the portion having the local temperature unevenness is nano-order and the coating film thickness is different from other portions due to the difference in the drying state. Even if there is a slight difference in thickness, the thickness changes abruptly at the boundary. Therefore, in the appearance, the part with local temperature unevenness is visually recognized as application unevenness (dryness unevenness) with a surface different from other parts. . Since the roll is in contact with the web 10 over the entire width, the coating unevenness becomes a straight line extending in the width direction (Y direction), which is similar to a so-called horizontal stage. Therefore, if the material of the surface of each roll in contact with the web 10 is a synthetic resin or synthetic rubber having a low thermal conductivity as described above, local temperature unevenness will not occur. Does not occur. Each roll need not be entirely made of synthetic resin or synthetic rubber, but only the outer peripheral surface portion of the roll contacting the web 10 may be made of synthetic resin or synthetic rubber, and the inner portion thereof may be made of metal or the like. . For example, the outer peripheral surface portion of the metal roll may be covered with a thin synthetic resin or synthetic rubber layer through the inner peripheral portion of a synthetic resin or synthetic rubber tube. Thus, as a material which covers the outer peripheral surface of a metal roll, you may use natural materials with small heat conductivity, such as leather, paper, and natural rubber.

  For the rotatable guide roll 9 on the downstream side of the dancer roll unit 2, the surface material of the portion in contact with the web 10 is made of synthetic resin or synthetic rubber for the same reason as the fixed rolls 21A, B, C, D, etc. It is preferable to use a material having a low thermal conductivity. That is, it is preferable that the material of all the roll surfaces which the web 10 contacts before reaching the backup roll 6 from the unwinding machine 3 which is an unwinding apparatus is a synthetic resin or a synthetic rubber.

  Next, on the downstream side of the guide roll 9, there is a backup roll 6 that wraps and supports the web 10 to which the tension T is applied on the downstream side of the dancer roll unit 2 that is a web material tension applying means. That is, the web 10 is supported by being wound around the backup roll 6 in a state where the tension T is applied. At the point where the winding ends, the web 10 is pulled in the horizontal direction (X direction) and further to the linear moving device 4 located downstream. The backup roll 6 is rotatable so as to follow the moving speed V determined by the linear moving device 4. In addition, the material of the surface (outer peripheral surface) of the backup roll 6 may be a metal, a synthetic resin, a synthetic rubber, or a ceramic. Since the web 10 moves and starts to contact the backup roll for a while, coating is performed, so even if there is a temperature difference between the backup roll 6 and the web 10, new local temperature unevenness is added. This is because it does not occur.

  As described above, on the downstream side of the backup roll 6, the web 10 is moved in the X direction (horizontal direction) by the linear moving device 4 at the moving speed V by the intermittent moving amount L. The linear moving device 4 is arranged below the web 10 and a linear guide 41 that freely guides the traveling body 42 in the X direction, a linear motor (not shown) that freely reciprocates the traveling body 42 in the X direction, and the web 10. And a fixed roll 43 attached to the traveling body 42 so as to be movable up and down on the upper side of the web 10. The web 10 can be nipped by sandwiching the web 10 from above and below with a fixed roll 43 that is a metal roll and a fixed nip roll 44 that is also a rotation-fixed rubber roll. Both the fixed roll 43 and the fixed nip roll 44 extend in the Y direction (direction perpendicular to the paper surface) which is the width direction of the web 10, and the Y direction dimension is longer than the width Lw of the web 10, so that the web 10 is nipped over the entire width. That is, the full width can be maintained. That is, the linear moving device 4 can be said to be a linearly moving device that linearly moves by the linear motor and conveys the web 10 by the intermittent movement amount L while holding the full width of the web 10 on the downstream side of the backup roll 6. The fixed roll 43 is preferably made of a hard material such as ceramic in addition to metal, and the top of the fixing roll 43 is preferably below the position of the top of the backup roll 6 in the vertical direction. Furthermore, the fixed nip roll 44 is moved up and down freely by an air cylinder (not shown). Accordingly, when the web 10 is nipped with the fixed roll 43, the fixed nip roll 44 is lowered, and when the nip is released, the fixed nip roll 44 is raised. The nip force of the web 10 is adjusted by the pressure of compressed air supplied to an air cylinder (not shown). In a state where the web 10 is nipped between the fixed nip roll 44 and the fixed roll 43, when the traveling body 42 is moved at the moving speed V in the X direction by a linear motor (not shown), the web 10 is conveyed at the moving speed V. At this time, since the constant tension T determined by the dancer roll unit 2 is constantly acting on the web 10, the tension T acts on a linear motor (not shown) as a load. The tension T is determined by gravity, does not vary with time, and can be adjusted to an optimum magnitude by the weight W of the weight 26. In this way, since a constant and appropriate load is always applied without time fluctuation, a linear motor (not shown) can be speed-controlled with very high accuracy. As a result, the traveling body 42 can be linearly moved at an extremely uniform speed, and as a result, the web 10 can be conveyed at an extremely uniform speed. Furthermore, this can be realized because the full width of the web 10 is held by the fixed nip roll 44 and the fixed roll 43. When the web 10 is only partially held, no matter how the traveling body 42 moves at a uniform speed, the web 10 is not conveyed at a uniform speed over the entire width because the expansion and contraction of the web 10 differs in the width direction.

  Next, on the downstream side of the linear moving device 4, when the web 10 is stationary, there is a stationary holding device 5 that nips the web 10 with the fixed roll 53 and the fixed nip roll 54 and holds the entire width. That is, the stationary holding device 5 is a device that holds the web 10 at the downstream side of the linear moving device 4 and holds the web 10 in its full width. In this apparatus, the fixed roll 53 is rotatably fixed to the main body 51 so as to be positioned below the web 10. The fixed nip roll 54 which is a rubber roll is attached to the elevating bracket 52 so as to be positioned on the upper side of the web 10 in a rotationally fixed manner. Since the elevating bracket 52 is attached to the main body 51 so as to be movable up and down, as a result, the fixed nip roll 54 can be lowered and the web 10 can be nipped with the fixed roll 53. Since both the fixed roll 53 and the fixed nip roll 54 extend in the Y direction, which is the width direction of the web 10, and the dimension in the Y direction is longer than the width Lw of the web 10, the web 10 can be nipped over the entire width as described above. . In addition, raising / lowering of the raising / lowering bracket 52 can be performed by the air cylinder which is not shown in figure. That is, when the nip is made, the lifting bracket 52 is lowered by the air cylinder, and when the nip is released, the air cylinder is raised.

  Further downstream of the stationary holding device 5 is a downstream conveyance unit 16 that conveys the web 10 to a downstream process. The downstream conveyance unit 16 includes a drive roll 161 that is longer in the width direction than the width Lw of the web 10 and a pair of rotatable end nip rolls 162 that nip only both ends of the web 10. The end nip roll is a rubber roll and can be moved up and down freely by an air cylinder (not shown). Further, the end nip roll 162 is located on the outer side in the width direction (Y direction) from the position where the web 10 is applied, and does not come into contact with the coating liquid. The driving roll 161 is driven by a servo motor or the like, and its peripheral speed is controlled to be slightly larger than the moving speed V of the web 10 by the linear moving device 4, and the web 10 is conveyed to the downstream process without sagging. be able to.

  Next, the configuration and function of each unit constituting the application portion of the intermittent application apparatus 1 will be described in detail.

  The coating unit 7 that actually performs coating includes a slit nozzle 70 that discharges and coats the coating liquid onto the web 10 supported by the backup roll 6, and the slit nozzle 70 is applied to the web 10 on the backup roll 6 with a predetermined amount. It consists of a proximity device 8 that brings it close to the gap.

  First, the slit nozzle 70 is configured such that a front lip 71 and a rear lip 72 extending in the width direction (Y direction) of the web 10 are overlapped in the Z direction via shims 78 and are integrally coupled by a plurality of connection bolts (not shown). Has been. A manifold 73 serving as a coating liquid storage unit is formed at the center of the slit nozzle 70, and this manifold 73 also extends in the width direction of the web 10. Above the manifold 73, there is a supply channel 79 through which the coating solution 12 is supplied. The coating solution 12 supplied from the supply channel 79 is stored in the manifold 73. Further, on the right side of the manifold 73, a slit 74 is formed as a slit-shaped flow path so as to communicate between the manifold 73 and the discharge port 76. The slit 74 also extends in the width direction of the web 10. An end of the slit 74 opposite to the manifold 73 in the X direction opens at the discharge port surface 75 to form a discharge port 76. The discharge port 76 discharges the coating liquid 12 stored in the manifold 73 through a slit 74 that communicates with the discharge port 76. The discharge port 76 is included in the discharge port surface 75, and has slopes 77 </ b> A and B adjacent to both sides of the discharge port surface 75 in the Z direction. Since the slit 74 functioning as a slit-shaped flow path is formed by the shim 78, the gap (measured in the Z direction) of the slit 74 is equal to the thickness of the shim 72. From the above, it can be said that the slit nozzle 70 is an applicator provided with the discharge port 76 for discharging the coating liquid 12 onto the web 10 supported by the backup roll 6.

  When the coating is performed, the proximity device 8 includes the discharge port surface 75 including the discharge port 76 of the slit nozzle 70 until the clearance 10 having a clearance CL is generated between the web 10 supported by the backup roll 6. Make it close. When the coating liquid 12 is discharged from the discharge port 76 of the slit nozzle 70 with a clearance CL of clearance, a bead 90 that is a liquid pool is formed between the discharge port surface 75 and the web 10, and stable coating is performed. Yes. The proximity device 8 includes a movable body 82 that supports the slit nozzle 70 and a linear guide 81 that guides the movable body 82 in the X direction (horizontal direction). Then, the slit nozzle 70 mounted on the movable body 82 can be freely reciprocated in the X direction by a driving device such as an air cylinder (not shown).

  A supply hose 101 connected from the supply flow path 79 to the coating liquid supply unit 100 is connected to the upstream side of the manifold 73 of the slit nozzle 70. When the coating liquid 12 is supplied from the coating liquid supply unit 100 to the slit nozzle 70, the coating liquid 12 is widened in the width direction of the web 10, which is the coating width direction, by the manifold 73, passes through the slit 74, and is discharged from the discharge port 76. It is discharged uniformly in the coating width direction.

  Now, the coating liquid supply unit 100 has a switching valve 102 for switching between passing and blocking of the coating liquid 12 flowing through the supply hose 101, a tank 110 for storing the coating liquid 12, and a predetermined positive pressure on the coating liquid 12 in the tank 110. The pressurizing unit 120 is made to act, and the atmospheric unit 130 for releasing the pressure in the tank 110 to the atmosphere. The pressurizing unit 120 and the atmospheric pressure unit 130 function as a pressure acting device that applies an arbitrary pressure equal to or higher than the atmospheric pressure to the coating liquid 12 in the tank 110. When the opening / closing valve 102 is switched in a state where the pressure is applied to the coating liquid 12 in the tank 110 by the pressurization unit 120, the supply of the coating liquid 12 from the tank 110 to the slit nozzle 70 is stopped. The magnitude of the pressure applied to the coating liquid 12 in the tank 110 is set according to the flow rate of the coating liquid 12 discharged from the discharge port 76 of the slit nozzle 70. From the above, it can be said that the coating liquid supply unit 100 is a coating liquid supply apparatus that supplies the coating liquid 12 to the slit nozzle 70 that is a coating device.

  Here, the pressurizing unit 120 includes a compressed air pipe 121 connected to the tank 110, a compressed air opening / closing valve 122 that performs the action and blockage of positive pressure by the compressed air, a compressed air regulator 123 that is set to an arbitrary magnitude (positive pressure), The air pressure source 124 is configured. With this configuration, a pressure (positive pressure) adjusted to an arbitrary magnitude can be applied to the coating liquid 12 in the tank 110. The atmospheric unit 130 includes an atmospheric pipe 131 connected to the tank 110 and an atmospheric opening / closing valve 132 that switches between atmospheric release and sealing. The tank 110 can be opened to the atmosphere or sealed at an arbitrary timing. The coating liquid supply unit 100 may be a pump that can instantaneously start and stop the supply of the coating liquid. In particular, a constant-capacity pump such as a syringe pump that can start and stop the supply of the coating liquid with high responsiveness by moving and stopping the piston is preferable.

  In the intermittent application apparatus 1 described above, the linear moving device 4, the proximity device 8, the unwinding machine 3, the coating liquid supply unit 100, and the like that are operated by the control signal are all electrically connected to the control device 140. Then, a control command signal is transmitted to each device or unit in accordance with an automatic operation program incorporated in the control device 140, and a predetermined operation for intermittent application is executed. When changing the conditions, if a change parameter is appropriately input to the operation panel 150, it is transmitted to the control device 140, and the change of the driving operation can be easily realized.

  Now, referring to FIG. 2, one embodiment of the intermittent coating method of the present invention in which the coating liquid 12 is coated on the web 10 that is intermittently moved by the intermittent movement amount L using the intermittent coating apparatus 1 is described in Step 1. The steps indicated by ˜6 will be described later. FIG. 2 is an explanatory view showing one aspect of the intermittent coating method according to the present invention.

  When FIG. 2 is seen, a part of schematic front view of the intermittent application apparatus 1 is shown. That is, the unwinding machine 3, the dancer roll unit 2, the guide roll 9, the backup roll 6, the slit nozzle 70 representing the coating unit 7, the linear moving device 4, the stationary holding device 5, the downstream transport unit 16, the coating liquid supply A supply hose 101 and an opening / closing valve 102 representing the unit 100 are shown. The web 10 is passed from the unwinder 3 to the downstream of the downstream conveyance unit 16. Further, the coating liquid 12 is also filled from the supply hose 101 to the slit nozzle 70 and can be discharged from the slit nozzle 70 at any time. Further, the dancer roll unit 2 is configured so that the tension T acting on the web 10 between the unroller 3 and the position nipped by the fixed roll 43 and the fixed nip roll 44 of the linear moving device 4 becomes a predetermined value. The weight W of the weight 26 has already been adjusted.

  2 (a) to 2 (c) and FIGS. 3 (d) to 3 (f) show situations corresponding to steps 1 to 6. In FIGS. 2A to 2C and FIGS. 3D to 3F, “close” on the right side of the open / close valve 102 means that the valve is closed (closes the valve), and “open” means that the valve is open (closed). Open the valve). Furthermore, the arrows indicate the operation direction of each device or unit and the flow direction of the coating liquid.

<Step 1> (Situation in FIG. 2A)
This is preparation step 1. Each device and unit is in its initial position. That is, the elevating rolls 22A, B, C of the dancer unit 2 are at the uppermost position Zm in the Z direction, and the linear moving device 4 stops the traveling body 42 at the movement start position Xs immediately to the right of the backup roll 6 and the fixed roll 43 and the fixed nip roll 44 nip and hold the web 10 with its full width. In the stationary holding device 5 on the downstream side of the linear moving device 4, the fixed nip roll 54 is on the upper side and the nip is released (not held). Further, in the downstream transport unit 16, the driving roll 161 is stopped, but the end nip roll 162 is lowered to nip both end portions of the web 10, and the position where the full width is held by the fixed roll 43 and the fixed nip roll 44. The downstream web 10 is held so that it does not sag. The slit nozzle 70 for coating is close to the backup roll 6 and the clearance between the discharge port surface 75 and the web 10 supported by the backup roll 6 is at a position where the clearance amount CL is present. In the coating liquid supply unit 100 (not shown) that supplies the coating liquid to the slit nozzle 70, the pressure regulator 123 applies a predetermined pressure so that the discharge flow rate from the slit nozzle 70 according to the coating thickness can be obtained. Is set. Since the pressure air opening / closing valve 122 is opened and the air opening / closing valve 132 is closed, the pressure of the magnitude set by the pressure air regulator is applied to the coating liquid 12 in the tank 110. Further, the opening / closing valve 102 is closed, and the coating liquid 12 is blocked here, but the coating liquid 12 can be supplied to the slit nozzle 70 at the timing when the opening / closing valve 102 is opened.

<Step 2> (Situation (b) in FIG. 2)
This is preparation step 2. The unwinding shaft 31 of the unwinding machine 3 is driven, the web 10 is unwound and stopped by the intermittent movement amount L, and the unwinding shaft 31 is fixed by a brake. Along with this, the lifting rolls 22A, B, C of the dancer roll unit 2 descend and stop at the preparation position Zp that is L / 6 below the uppermost position Zm that is the initial position. As a result, the web 10 is stored (accumulated) in the dancer roll unit 2 by the intermittent movement amount L. During the operation and stop of the lifting rolls 22A, 22B and 22C, the initially set tension T acts on the web 10.

<Step 3> (Situation (c) in FIG. 2)
This is an intermittent application start process. The linear moving device 4 and the drive roll 161 of the downstream transport unit 16 are started to be driven by a signal from the control device 140. As a result, the traveling body 42 at the movement start position Xs starts moving at the moving speed V in the X direction with the fixed roll 43 and the fixed nip roll 44 holding the entire width of the web 10. The movement starts at the movement speed V. The downstream transport unit 16 starts transporting the web 10 at a speed (V + α) at which the web 10 on the downstream side of the position where the nip is held by the fixed roll 43 and the fixed nip roll 44 does not sag. As the web 10 starts to be transported, the lifting rolls 22A, B, C of the dancer roll unit 2 start to move upward from the preparation position Zp, but even when the lifting rolls 22A, B, C are stopped, Even when the movement is started, the tension acting on the web 10 is the initially set tension T. Therefore, the load acting on the linear moving device 4 is also a constant tension T and is unchanged. Accordingly, the speed of the linear moving device 4 is controlled with very high accuracy, so that the web 10 can be conveyed (moved) at a very uniform speed. When the application start position of the web 10 comes to the position of the discharge port 76, the open / close valve 102 is switched from closed to open. As a result, the coating liquid 12 supplied from the coating liquid supply unit 100 to the slit nozzle 70 is discharged from the discharge port 76 of the slit nozzle 70 and starts to be applied to the web 10 supported by the backup roll 6.

  That is, in this process, the linear moving device 4 holds the web 10 in its full width, and moves it linearly by an intermittent movement amount L at a constant moving speed V, thereby raising and lowering rolls 22A that are dancer rolls on which the web 10 is suspended. B and C are moved upward in the direction of gravity, and the web 10 to which a constant tension T is constantly applied by the suspended lifting rolls 22A, 22B and 22C is supported by the backup roll 6 at the position where the coating liquid is supplied. The coating liquid 12 supplied from the coating liquid supply unit 100 which is an apparatus is discharged from the slit nozzle 70 which is a coating device, and the coating liquid 12 is applied onto the web 10.

  When the application start position of the web 10 reaches the position of the discharge port 76, the moving speed of the web 10 may have reached the moving speed V or before reaching the moving speed V. What is necessary is just to select the moving speed of the web 10 at the time of starting application | coating by using the moving direction film thickness profile of an application | coating start part as a parameter | index.

<Step 4> (Situation (d) in FIG. 3)
This is an intermittent application end process. When the application end position of the web 10 comes to the position of the discharge port 76 and application is performed for the application length Lc in the moving direction of the web 10, the open / close valve 102 is switched from open to closed, and the application liquid 12 to the slit nozzle 70 is applied. The supply is stopped and the application is finished. As a result, an intermittent coating film M having a coating length Lc is formed on the web 10. The intermittent movement amount L> the coating length Lc. Depending on the timing at which the on-off valve 102 is closed, the slit nozzle 70 may be moved to the left by the proximity device 8, and the slit nozzle 70 may be separated from the web 10 supported by the backup roll 6. Even after the application is completed, the web 10 continues to move at the moving speed V. However, as the traveling body 42 stops at the movement end position Xe separated from the movement start position Xs by the intermittent movement amount L, the movement stops. In response to this, the drive roll 161 of the downstream transport unit 16 is stopped so that the web 10 on the downstream side does not sag from the position where the linear moving device 4 holds the nip. As the movement of the web 10 stops, the lifting rolls 22A, 22B, and 22C of the dancer roll unit 2 also stop rising and stop at the uppermost position Zm that is the initial position. Note that the same constant tension T acts on the web 10 during and after movement.

<Step 5> (Situation (e) of FIG. 3)
This is a return start process. First, the stationary holding device 5 is operated, the fixed nip roll 54 is lowered, the portion where the web 10 is not applied is sandwiched between the fixed roll 53 and the full width nip is held. Subsequently, the fixed nip roll 44 of the linear moving device 4 is raised, and the full width nip holding of the web 10 by the linear moving device 4 is released. Then, the linear moving device 4 is started to be driven in the opposite direction, and the traveling body 42 is started to move toward the movement start position Xs in the direction opposite to the moving direction for coating.

<Step 6> (Situation (f) in FIG. 3)
This is a return completion process. When the traveling body 42 of the linear moving device 4 returns to the movement start position Xs, it stops. Subsequently, the fixed nip roll 44 is lowered, and the web 10 is held at the full width nip by the fixed roll 43 and the fixed nip roll 44 at the movement start position Xs.

  Thereafter, the same procedure of steps 1 to 6 is repeated, and the next intermittent application is subsequently performed.

  In the intermittent coating method described above, the intermittent coating film M having the coating length Lc is formed by discharging / stopping the coating liquid 12 from the slit nozzle 70 once while the web 10 moves by the intermittent movement amount L. Although formed, the discharge / discharge stop of the coating liquid 12 from the slit nozzle 70 may be repeated a plurality of times, and a plurality of intermittent coating films M may be formed during one movement of the web 10. For example, the coating length Lc = L / 4, and while the web 10 is moved by the intermittent movement amount L, the coating liquid is discharged / stopped from the slit nozzle 70 at a predetermined position of the web 10 three times to perform coating. Three intermittent coating films of length L / 4 may be formed.

  Furthermore, the traveling body 42 of the linear moving device 4 is moved, and during the intermittent movement of the web 10 once, the coating liquid is discharged / stopped and intermittent application is performed. It may be repeated a plurality of times before reaching the end position Xe. For example, the length of the web 10 for 3 L is stored in the dancer roll unit 2 with respect to one intermittent movement amount L (the traveling body 42 can move by Xe−Xs = 3 L), and Step 3 and Step 4 are performed. Thus, the discharge / discharge stop of the coating liquid from the slit nozzle 70 is performed only once for the intermittent movement amount L of the web 10 once, and the intermittent coating film M having the coating length Lc (L> Lc) is formed. Form. Steps 3 and 4 for performing such intermittent coating may be repeated three times to form three intermittent coating films M having a coating length Lc between the lengths 3L of the web 10.

  Further, the web 10 was unwound from the unwinding shaft 31 of the unwinder 3 by the intermittent movement amount L, and the web 10 was stored in the dancer roll unit 2 by the intermittent movement amount L in step 2. After this operation is performed for the second time or later, in the first step 5 before the second step 2, the web 10 is held at the full width nip by the stationary holding device 5 and then performed in parallel with other operations. Good. Thereby, the cycle time of intermittent application can be shortened.

  The tension T applied to the web 10 between the unwinder 3 and the position where the full width nip is held by the linear moving device 4 is preferably 1 to 100 N / m, more preferably 2 to 40 N / m. To do. When the tension T is 1 N / m or more, the occurrence of local sag on the web 10 can be suppressed, and the web 10 can be stably conveyed. If the tension T is 100 N / m or less, the load applied to the linear moving device 4 does not become too large, so that the speed of the linear motor of the linear moving device 4 can be controlled with high accuracy, and as a result, the web 10 is conveyed at a uniform speed. it can. In the intermittent coating apparatus of the present invention, the tension in the above preferred range is always constant and does not fluctuate over time, but acts on the web 10. Therefore, the load on the linear motor used in the linear moving apparatus 4 is also appropriately large. The time will not change. As a result, the speed of the linear motor can be controlled with very high accuracy, and the web 10 can be conveyed at a very uniform speed. As a result, the coating thickness distribution in the moving direction (X direction) can be made extremely uniform. it can.

  Furthermore, as described above, the roll contacting the web 10 between the unwinder 3 and the backup roll 6 is preferably made of a synthetic resin or synthetic rubber having a low thermal conductivity as the material of the surface portion to be contacted. This is the above-described Step 1 to Step 6, and when the web 10 before application is stationary, if the material has a small thermal conductivity, the amount of heat transfer is small, so the web 10 in contact with the roll is localized. This is because there is no change in temperature, and even if coating is performed thereafter, uneven coating such as horizontal unevenness does not occur. If the material has a high thermal conductivity such as a metal roll, the amount of heat transfer becomes large, and the temperature of the portion of the web 10 that is in contact with the roll locally changes. When a part that maintains such a local temperature change is applied, the drying state changes between the part that has been in contact with the roll and the other part, and a different surface state is observed as uneven application. Such coating unevenness is peculiar to intermittent coating in which the web 10 is stationary for a relatively long time. In the continuous application in which the web 10 is continuously moved, no local temperature change occurs in the web 10, so that the uneven coating described above does not occur. In addition, when the material which does not generate | occur | produce the said application | coating unevenness is divided according to heat conductivity, it is a material in which heat conductivity becomes like this. Preferably it is 5 W / (m * K) or less, More preferably, it is 1 W / (m * K) or less.

  The web material to which the intermittent coating apparatus and the intermittent coating method of the present invention can be applied is not particularly limited as long as it is a continuous material, and can be suitably applied to plastic films, paper, metal thin plates, metal foils, nonwoven fabrics, and the like.

  Further, the downstream process after coating is not particularly limited, and the web 10 on which the intermittent coating film M is formed can be delivered to any process such as a drying process or a sheet-feeding process (fixed size cutting process).

  The coating solution applicable to the present invention described above has a viscosity of 1 to 100000 mPa · S and is preferably a Newtonian from the viewpoint of coating properties, but can also be applied to coating solutions having thixotropy. Specific examples of the coating solution that can be applied include a planarizing polyimide solution, an overcoat material, a protective coating solution, a resist solution, a colored layer coating solution, and an LED fluorescent light emitting layer coating solution.

  The present invention will be specifically described below with reference to examples.

(Example)
Using the intermittent coating apparatus 1 shown in FIG. 1 as a coating sheet manufacturing apparatus, a width of 200 mm and a length of 400 mm (X direction) are formed on a PET film having a width of 250 mm (Y direction) and a thickness of 0.1 mm as the web 10. 100 phosphor sheets having a wet thickness of 50 μm were formed at a pitch of 500 mm in the X direction. The phosphor sheet film paste had a viscosity of 5000 mPa · s and a solid content of phosphor particles and resin having a concentration of 40%.

  According to this paste, the slit nozzle 70 has a width (Y direction) length of 200 mm, a Z direction length (gap) of 0.3 mm, and a slit 74 length of 10 mm in FIG. , Was used. Then, the slit nozzle 70 is brought close to each other so that the clearance CL from the surface of the web 10 supported by the backup roll 6 having an outer diameter of 200 mm and a length of 300 mm in the Y direction to the discharge port surface 75 of the slit nozzle 70 is 130 μm. It was. Further, the backup roll 6 is formed of SUS304 with a hard chromium plating of 100 μm to form an outer peripheral surface. However, the guide roll 9 and the fixed rolls 21A, B, C, D, The elevating rolls 22A, B, and C were all made of polyacetal cylinders having an outer diameter of 50 mm and a length in the Y direction of 300 mm. The web 10 was wound around the guide roll 9 at a winding angle of 60 degrees, and the length in the moving direction of the web 10 from the winding center to the coating position on the backup roll 6 was 300 mm. Furthermore, the fixed rolls 43 and 53 are both SUS304 cylinders with an outer diameter of 50 mm and a Y-direction length of 300 mm, and the fixed nip rolls 44 and 54 are NBR rubber rolls with an outer diameter of 50 mm and a Y-direction length of 300 mm. The rubber thickness was 3 mm. Further, the driving roll 161 of the downstream transport unit 16 has an outer diameter of 100 mm and a length in the Y direction of 300 mm, and is formed by applying hard chromium plating to the SUS304 metal 100 μm to form an outer peripheral surface. Further, the pair of end nip rolls 162 were NBR rubber rolls having an outer diameter of 50 mm and a Y-direction length of 15 mm, and the NBR rubber thickness was 3 mm. Two end nip rolls 162 were arranged at both ends in the width direction (Y direction) so as to be able to hold the nip within a range of 15 mm from the both ends in the width direction of the web 10. Furthermore, the dancer roll unit 2 so that the tension T = 5N (= 20 N / m) acts on the full width of the web 10 between the unwinder 3 and the position where the full width nip is held by the linear moving device 4. The weight W of the weight 26 was adjusted.

  Subsequently, the pressurized air regulator 123 was set so that pressurized air with a pressure of 0.22 MPa acted on the coating liquid 12 in the tank 110. The magnitude of this pressure was determined by investigating beforehand that the web 10 can be applied with a wet thickness of 50 μm with the slit nozzle 70 when moving at a moving speed V = 50 mm / s.

  With all the above preparations completed, Steps 1 to 6 of the coating method of the present invention were faithfully executed. First, the unwinding machine 3 was driven, and the intermittent movement amount L = 500 mm was unwound and stored in the dancer roll unit 2. Driving of the linear moving device 4 was started, and the web 10 was started to move at a moving speed V = 50 mm / s. When the traveling body 42 holding the web 10 with the full width nip moved 50 mm from the movement start position Xs, the opening / closing valve 102 was switched from closed to open to start application. Then, when the traveling body 42 moved 450 mm from the movement start position Xs, the opening / closing valve 102 was switched from open to closed to finish the application. The traveling body 42 stopped at a movement end position Xe that was 500 mm away from the movement start position Xs, and the movement of the web 10 was stopped accordingly. As a result, an intermittent coating film M having a wet thickness of 50 μm, a coating length Lc = 400 mm, and a width of 200 mm could be formed. Then, after the full width nip holding of the linear moving device 4 was released, the traveling body 42 was returned to the movement start position Xs, and Step 1 to Step 6 were completed. Thereafter, Step 1 to Step 6 were repeated 100 times in the same manner. As a result, 100 phosphor sheet films having a width of 200 mm, a length of 400 mm (X direction), and a wet thickness of 50 μm could be formed on the web 10 at a pitch of 500 mm in the X direction. The intermittently applied phosphor sheet film was dried in the downstream process, and the coating thickness after drying was 20 μm. When the thickness distribution in the moving direction (X direction) of the 100 phosphor sheet films (intermittent coating film) after drying was measured, except for 10 mm at the start and end of coating, that is, 10 mm from the coating start position. It was confirmed that an intermittent coating film having a very uniform thickness could be formed with a thickness unevenness of ± 1% or less in a range of ˜390 mm. In addition, since coating unevenness was not observed at all in any of the 100 phosphor sheet films, it was shipped as a class A product.

(Comparative example)
The intermittent application was performed under exactly the same conditions as in the example except that the guide roll 9 was an aluminum roll having an outer diameter of 50 mm and a Y-direction length of 300 mm. As a result, all of the 100 phosphor sheet films had an uneven thickness in the moving direction (X direction) of ± 1% or less, and a coating film having a very uniform thickness was obtained. However, in all of the 100 phosphor sheet films, horizontal unevenness occurred over the entire width of the coating film at a position of 250 mm in the moving direction (X direction) of the web 10 from the coating start position. The length of the horizontal unevenness in the X direction was 16 mm. There were 100 transverse irregularities over the entire width of the web 10 having a length of 16 mm in the X direction at a pitch of 500 mm. In addition, the location where the horizontal unevenness was generated corresponded to the position where the web 10 was stationary before application and in contact with the metal guide roll 9. When the thickness of the portion where the horizontal unevenness occurred was measured, the thickness was only 0.02 μm thinner than the normal portion. Although there was such unevenness in the horizontal stage, it was within the acceptable standard for unevenness, and the thickness uniformity of the intermittent coating film was acceptable, so it could be shipped as a Class B product.

  The present invention is suitably used for the production of optical films used for displays and the like, and phosphor sheets used for white LEDs and the like, and a coating liquid is mainly applied to a web-like continuous substrate. It can be used for producing a large number of coating films having a predetermined length and a uniform thickness by intermittent application.

DESCRIPTION OF SYMBOLS 1 Intermittent coating device 2 Dancer roll unit 3 Unwinder 4 Linear moving device 5 Static holding device 6 Backup roll 7 Coating unit 8 Proximity device 9 Guide roll 10 Web 12 Coating liquid 16 Downstream conveyance unit 21A, B, C, D Fixed roll 22A, B, C Elevating roll 23 Connecting plate 24 Linear guide 25 Pulley 26 Weight 27 Wire 31 Unwinding shaft 41 Linear guide 42 Traveling body 43 Fixed roll 44 Fixed nip roll
51 Main Body 52 Lifting Bracket 53 Fixed Roll 54 Fixed Nip Roll
70 Slit nozzle 71 Front lip 72 Rear lip 73 Manifold 74 Slit 75 Discharge port surface 76 Discharge port 77A, B Slope 78 Shim 79 Supply channel 81 Linear guide 82 Movable body 90 Bead 100 Coating liquid supply unit 101 Supply hose 102 Open / close valve 110 Tank 120 Pressure unit 121 Pressure air piping 122 Pressure air opening / closing valve 123 Pressure air regulator 124 Pressure air source 130 Atmospheric unit 131 Atmospheric piping 132 Atmospheric opening / closing valve 140 Controller 150 Operation panel 161 Driving roll 162 End nip roll CL Clearance amount (clearance (clearance)) Length (unit of length))
L Intermittent movement amount Lc Application length Lw Web 10 width (Y-direction dimension)
M Intermittent coating film T Tensile force acting on web 10 Movement speed W of web 10 Weight of weight 26 Xs Movement start position Xe of traveling body 42 Xm movement end position Zm of traveling body 42 Lifting rolls 22A, B , C uppermost position Zp in the Z direction Preparation positions in the Z direction of the lifting rolls 22A, B, C

Claims (3)

  An intermittent coating apparatus that intermittently moves a web material to form a coating film intermittently, and includes an unwinding device that intermittently unwinds the roll-shaped web material by an intermittent movement amount, and the unwound web A web material tension applying means for applying tension to the web material by suspending a dancer roll movable in the gravity direction on the material, and a backup roll for winding and supporting the web material to which tension is applied downstream thereof, A linear movement device that moves the web material by an amount of intermittent movement while holding the full width of the web material on the downstream side of the backup roll, and a stationary holding that holds the web material at the downstream side of the linear movement device and holds the full width. An apparatus, an applicator provided with a discharge port for discharging the coating liquid onto the web material supported by the backup roll, and a coating liquid supply device for supplying the coating liquid to the applicator. Intermittent coating apparatus, characterized in that to obtain.   Furthermore, the material of the surface of all the rolls which a web material contacts until it reaches a backup roll from the said unwinding apparatus is a synthetic resin or a synthetic rubber, The intermittent application apparatus of Claim 1 characterized by the above-mentioned.   An intermittent application method for applying a coating liquid to an intermittently moving web material using the intermittent application device according to claim 1, wherein the web material is held at a constant speed while maintaining the full width by the linear movement device. By moving the dancer roll on which the web material is suspended in a straight line by the amount of intermittent movement, the web material to which constant tension is constantly applied by the suspended dancer roll is moved to the backup roll. An intermittent coating method characterized in that, at a supported position, the coating liquid supplied from the coating liquid supply device is discharged from the coating device, and the coating liquid is applied onto the web material.

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