JP2001079468A - Roller coating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to uniformly coat a coating object matter with a coating liquid, prevent the coating liquid from being spilled, keep the concentration of the coating liquid constant and enable easy cleaning of the coating liquid. SOLUTION: An air pump 17 is started to supply pressurized air to a resist liquid feed tank 11. At this moment, the opening of a throttling valve 16 is adjusted so as to keep air pressure constant. Resist liquid 12 in the resist liquid feed tank 11 is made to flow through a flow meter 10 via a supply pipe 9 and is discharged through a discharge hole of a resist liquid feed nozzle 6 and absorbed by a sponge 4 of a coating roll 1. A printed circuit board P is sandwiched between the coating rolls 1 that are being rotatively driven and the resist liquid 12 squeezed from the sponge 4 of the coating rolls 1 is coated on a surface of the printed circuit board. The residual excess resist liquid is sucked by a resist suction nozzle 20. This suction is performed by sucking air pressure in a resist liquid recovery tank 23 so as to form a negative pressure with constant suction pressure and suction volume by driving a suction pump 28.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a roller coating apparatus. More specifically, resist liquid on printed circuit boards, etc.
The present invention relates to a roller coating device for thinly applying a liquid such as paint.

[0002]

2. Description of the Related Art Ink,
Roller coating methods for applying liquid materials such as paint, dyes, cleaning liquids, chemicals, adhesives, and detergents are known and commonly used. For example, Japanese Patent Publication No. 6-47089 discloses a coating roll in which a groove for holding a coating liquid is formed on the outer periphery of a coating roll for applying the coating liquid. The coating amount of this coating roll is defined by the amount of pushing the doctor bar into the coating roll. In such a conventional method, it is difficult to supply a constant coating liquid, and an extra coating liquid may be generated. As a result, there has been a problem that a uniform coating thickness cannot be secured.

[0003]

SUMMARY OF THE INVENTION The present invention has been made under the above-mentioned technical background, and achieves the following objects. An object of the present invention is to provide a roller coating apparatus capable of uniformly applying a coating liquid to an object to be coated. Another object of the present invention is to provide a roller coating apparatus which does not cause spillage of a coating liquid. Still another object of the present invention is to provide
An object of the present invention is to provide a roller coating device in which the concentration of a coating liquid is kept constant. Still another object of the present invention is to provide a roller coating apparatus that can easily clean a coating liquid.

[0004]

The present invention employs the following means to achieve the above object. The roller coating apparatus of the present invention is driven to rotate, and a coating roll for transferring and coating the coating liquid on the surface of the object to be coated while holding the coating liquid on the outer periphery,
A support roll that has a rotation axis parallel to the rotation axis of the coating roll and transports the object to be sandwiched between the coating roll and a liquid that is disposed on the outer periphery of the coating roll and discharges a coating liquid; A supply nozzle, a liquid supply unit for supplying a pressurized coating liquid to the liquid supply nozzle, a suction nozzle arranged on an outer periphery of the coating roll, and suctioning an excess coating liquid from the suction nozzle And a liquid suction means.

The coating roll may be arranged in place of the support roll, and both sides of the object to be coated may be simultaneously coated with a coating liquid. Further, it is preferable that the axis of the coating roll or the support roll is disposed horizontally.

It is preferable that a porous sponge impregnated with a coating liquid is disposed on the outer periphery of the coating roll. Further, the coating roll may have a groove formed on the outer periphery. The rotation direction of the coating roll is the same direction and the same speed at the position where the coating roll comes into contact with the object to be coated.

The liquid supply means may be constituted only by a normal pressure pump for directly supplying the coating liquid. However, the liquid supply means may be a closed liquid supply tank for storing the coating liquid and a liquid supply tank. It is desirable that the air pump include an air pump for supplying compressed air and a throttle valve for adjusting the air pressure of the air pump.

The liquid suction means may be constituted by a pump for directly sucking the coating liquid. The liquid suction means may include a sealed liquid suction tank for storing the coating liquid and a liquid suction tank for sucking air in the liquid suction tank. And a throttle valve for adjusting the air pressure of the suction pump.

[0009]

Next, an embodiment of the present invention will be described. FIG. 1 is a view showing an outline of an apparatus in which a roller coating apparatus of the present invention is applied to a coating apparatus for applying a resist liquid to a printed circuit board. The pair of coating rolls 1 are cylindrical.
A rotary shaft 2 is provided at the center thereof, and the rotary shafts 2 are arranged so as to be parallel to each other, and are rotatably supported by bearings (not shown) supported and fixed to a machine frame 3. The rotating shaft 2 is rotationally driven by a driving mechanism (not shown) at the same rotational speed and in the opposite direction.

A resist liquid is applied between the coating rolls 1 while a printed substrate P as an object to be coated is sandwiched and transferred. Therefore, in order to adjust the thickness of the printed circuit board P, the thickness of the resist solution applied, and the like, the intervals can be adjusted by an interval adjusting mechanism (not shown) provided with screws. A pipe is inserted and fixed to the outer periphery of the rotating shaft 2, and the outer periphery of the pipe is covered with a sponge 4 made of rubber or synthetic resin elastic body with a porous structure having a spongy structure.

Since the sponge 4 is made of a porous structure, it has a property of appropriately impregnating the resist solution. The coating roll 1 is constituted by the rotating shaft 2, the pipe on the outer periphery thereof, and the sponge 4. The outer periphery of the coating roll 1 is arranged along the coating roll 1 so as to cover the nozzle body 7. The nozzle body 7 has a function of removing the excess resist solution on the outer periphery of the coating roll 1 and a function of making the impregnation amount different depending on the position, that is, a function of a kind of doctor blade.

The nozzle body 7 is fixed to the machine frame 3 via a packing 5 by bolts (not shown). The packing 5 is arranged to seal a resist solution in the pressure accumulating chambers 8 and 21 described below. A resist solution supply nozzle 6 is formed and arranged in the nozzle body 7 by piercing along a central axis of the rotating shaft 2. The resist liquid supply nozzle 6 is a discharge hole for discharging the resist liquid. After all, the resist solution supply nozzle 6 is formed integrally with the nozzle body 7. A pressure accumulating chamber 8 for accumulating pressure is formed at the rear end of the resist liquid supply nozzle 6 inside the nozzle body 7, and the pressurized resist liquid is supplied to the accumulating chamber 8.

One end of a supply pipe 9 is connected to the pressure accumulating chamber 8, and the other end is connected to a resist liquid supply tank 11. A flow meter 10 with a throttle valve (not shown) is provided in the middle of the supply pipe 9.
Are placed and connected. The flow meter 10 is an instrument for measuring the flow rate of the resist solution 12 in the resist solution supply tank 11. Its structure and function are well known and will not be described in detail here. The resist solution supply tank 11 is a sealed tank for storing the resist solution 12.

The supply system of the supply pipe 9 includes a resist solution 12
There is no pumping device arranged to supply the water. A resist solution pressurizing means 15 for increasing the pressure in the sealed resist solution supply tank 11 and supplying the resist solution 12 to the resist solution supply nozzle 6 via the supply pipe 9 is provided. The resist solution pressurizing means 15 includes an air pump 17 for pressurizing and sending air, a throttle valve 16 for controlling the pressure of the pressurized air, a pipe 18 and the like.

By adjusting the opening of the throttle valve 16,
It controls the amount and pressure of air that flows into the resist liquid supply tank 11. By this adjustment, the amount of the resist liquid discharged from the resist liquid supply nozzle 6 is determined.
On the other hand, a resist liquid suction nozzle 20 is arranged in the nozzle body 7 in contact with the outer periphery of the coating roll 1 at an angle from the resist liquid supply nozzle 6. Regis liquid suction nozzle 20
There are a plurality of suction holes for sucking excess resist solution.

At the rear of the resist solution suction nozzle 20, a pressure accumulating chamber 21 for accumulating pressure is arranged to communicate. The accumulator 21 is connected to a resist solution recovery tank 23 through a pipe 22. The resist solution collecting tank 23 is provided with a resist solution sucking means 25 for reducing the pressure inside the resist solution collecting tank 23 to a negative pressure in order to suck excess resist solution from the resist solution sucking nozzle 20. The resist solution suction means 25 includes a suction pump 28 for sucking air, a throttle valve 27 for controlling the suction pressure of air, a pipe 26 and the like. Since the throttle valve 27 includes a pressure gauge, the magnitude of the suction pressure can be measured. By adjusting the suction amount of the resist solution suction means 25, the suction amount and pressure of the resist solution from the resist solution suction nozzle 20 can be adjusted.

(Operation of First Embodiment) Next, the operation of the first embodiment will be described. The air pump 17 is activated to supply pressurized air to the resist liquid supply tank 11. At this time, the opening degree of the throttle valve 16 is adjusted to keep the air pressure constant. Resist solution 12 in resist solution supply tank 11
Is supplied to the accumulator 8 through the flow meter 10 via the supply pipe 9. The resist liquid in the pressure accumulating chamber 8 is discharged from the discharge holes of the resist liquid supply nozzle 6 and is absorbed by the sponge 4 of the coating roll 1.

The printed circuit board P is sandwiched between the coating rolls 1 which are driven to rotate, and is transferred in a tangential direction.
During this transfer, the resist liquid that has oozed from the sponge 4 of the coating roll 1 is applied to the surface of the printed circuit board P. The remaining resist solution applied is sucked by the resist solution suction nozzle 20. In this suction, the suction pump 28 is started, and the resist solution collection tank 23 is kept at a constant suction pressure and suction amount.
This is performed by suctioning the air pressure inside to make the pressure negative.

As can be understood from the above configuration, the resist liquid is supplied from the resist liquid supply nozzle 6 to the sponge 4 of the coating roll 1, and the excess resist liquid is sucked by the resist liquid suction nozzle 20. Is applied to the surface of the printed circuit board P. In addition, by adjusting the air pressure on the supply side and the negative pressure on the suction side, liquid spill does not occur even if the coating roll 1 is disposed above the printed circuit board P.

In addition, since a new resist solution is constantly sent, there is also an effect that the concentration of the solution is kept constant. Due to the elasticity of the sponge 4 of the coating roll 1, it is possible to follow a warp or a flaw of the object to be coated. Even when there is no object to be applied between the application rolls 1, the supply and circulation of the liquid are performed, and stable application is possible. Further, if the object to be coated is within the width of the sponge 4 of the coating roll 1, no operation for changing the size of the object to be coated is required. The cleaning operation of the coating roll 1 can be easily performed by circulating the cleaning liquid instead of the resist liquid.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The following numerical values were employed in order to form a resist photosensitive film of 2-4 .mu.m on both sides of a printed board P at a coating speed of 2 m / min. Regarding the size of the coating roll 1, the effective coating width is 600 mm, the length is 700 mm, and the diameter is 40 mm. The diameter of the discharge hole of the resist liquid supply nozzle 6 is 0.5
They are arranged at intervals of 6 mm in mm. Regis liquid suction nozzle 2
The 0 suction holes are 1 mm in diameter and are arranged at 6 mm intervals.
Pressurized air for supply is 0.05-0.3 Mpa.

(Other Embodiments) FIG. 2 is a side view of a roller coating apparatus in which a coating roll is disposed only on the upper surface. In the second embodiment, the coating roll 1 is disposed on the upper surface of the printed circuit board, and the support roller 30 is disposed on the lower surface. FIG. 3 is a side view of a roller coating device in which a coating roll is disposed only on the lower surface. Embodiment 3
The coating roll 1 is arranged on the lower surface of the printed circuit board, and the support roller 30 is arranged on the upper surface.

In the above-described embodiment, the resist liquid is applied to the printed circuit board, but the present invention is not limited to this. For example, ink, paint, dye,
Any material may be used as long as it applies a liquid such as a cleaning liquid, a chemical, an adhesive, or a detergent. Furthermore, even if it is not a plate shape or a flat shape such as a sheet, the material is a roll shape and the material is also a flexible printed circuit board, a plastic sheet, paper,
Films and the like are also possible.

Although the above-described coating roll 1 has the sponge 4 disposed thereon, the same coating can be performed even if the coating roll 1 has a groove formed on the outer peripheral surface or a non-woven fabric wound.

[0025]

According to the roller coating apparatus of the present invention, the coating liquid can be uniformly applied to the object to be coated, the coating liquid does not spill, the concentration of the coating liquid is kept constant, and the cleaning of the coating liquid is performed. It has effects such as easiness.

[Brief description of the drawings]

FIG. 1 is a view schematically showing an apparatus in which a roller coating apparatus of the present invention is applied to a resist liquid application apparatus on a printed circuit board.

FIG. 2 is a side view of a roller coating device in which a coating roll is disposed only on an upper surface.

FIG. 3 is a side view of a roller coating apparatus in which a coating roll is disposed only on a lower surface.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Coating roll 2 ... Rotating axis 3 ... Machine frame 4 ... Sponge 5 ... Doctor blade 6 ... Resist liquid supply nozzle 7 ... Discharge nozzle main body 10 ... Flow meter 11 ... Resist liquid supply tank 20 ... Resist liquid suction nozzle 23 ... Resist Liquid recovery tank

Claims (6)

[Claims] 1. A coating roll that is driven to rotate, holds a coating liquid on its outer periphery, and transfers and applies the coating liquid to the surface of an object to be coated, and a rotation axis parallel to a rotation axis of the coating roll. A support roll that includes the coating roll and transports the object to be sandwiched between the coating roll, a liquid supply nozzle that is disposed on an outer periphery of the coating roll, and that discharges a coating liquid, and is pressurized by the liquid supply nozzle. A roller supply device comprising: a liquid supply unit configured to supply the applied coating liquid; a suction nozzle disposed on an outer periphery of the coating roll; and a liquid suction unit configured to suction excess coating liquid from the suction nozzle. 2. The roller coating apparatus according to claim 1, wherein the coating roll is disposed in place of the support roll, and both sides of the object are coated with a coating liquid. 3. The roller coating apparatus according to claim 1, wherein an axis of the coating roll or the support roll is horizontally arranged. 4. The roller coating apparatus according to claim 1, wherein a porous sponge impregnated with a coating liquid is disposed on an outer periphery of the coating roll. 5. The liquid supply device according to claim 1, wherein the liquid supply unit is closed by a liquid supply tank for storing a coating liquid, and is pressurized by the liquid supply tank. A roller coating device, comprising: an air pump for supplying air; and a throttle valve for adjusting the air pressure of the air pump. 6. The liquid suction means according to claim 1, wherein the liquid suction means sucks air in the liquid suction tank and a sealed liquid suction tank for storing a coating liquid. And a throttle valve for adjusting the air pressure of the suction pump.