JP2022113869A - Coating applicator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating applicator which can form a coating film having excellent smoothness.

SOLUTION: A coating applicator of the invention applies a paint to a base material P and includes a spreader roll 1, a doctor roll 2, and a receiving member 3. In the coating applicator of the invention, the receiving member 3, the spreader roll 1, and the doctor roll 2 form a liquid reservoir part 4 so that the paint adheres to the spreader roll 1 and the doctor roll 2. The receiving member 3 can be provided at the outer side relative to the spreader roll 1 and the doctor roll 2. The spreader roll 1 can be configured to rotate in an opposite direction of a rotation direction of the doctor roll 2.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2022,JPO&INPIT

Description

TECHNICAL FIELD The present invention relates to a coating device used for coating a substrate with a coating material.

Resist paints, conductive paints, insulating paints, protective paints, reinforcing paints, UV light shielding paints, antistatic paints on the surface of substrates, films, sheets, plates, panels, etc. (hereinafter collectively referred to as "base materials") , colored paints, functional coating agents, etc. (hereinafter collectively referred to as "paints") may be applied. For example, a case where a resist is applied to a printed wiring board and a case where an adhesive is applied to a copper foil can be mentioned.

Conventionally, as an apparatus for coating a base material with a coating material, there has been known one equipped with a coating roll for coating the coating material on the base material, a doctor roll for supplying the coating material to the coating roll, and a coating container for storing the coating material. (Patent Document 1). In this apparatus, the paint in the paint container is picked up by the doctor roll, transferred from the doctor roll to the application roll, and transferred from the application roll to the substrate, thereby applying the paint to the substrate.

Japanese Patent No. 4074293

However, in the coating apparatus, only the doctor roll is in direct contact with the coating material. It will depend on the smoothness of the paint, the amount of paint transferred from the doctor roll to the applicator roll, and the smoothness of the transferred paint.

For this reason, for example, if the paint on the surface of the doctor roll lacks smoothness, the paint transferred to the surface of the coating roll becomes uneven, and as a result, the film thickness of the paint transferred to the substrate becomes uneven.

Since the smoothness of the coating film applied to the base material affects the mounting density of electronic components, it is said that the coating film should be as smooth as possible. With the advent of the 5G era and the increasing density of substrates, this demand is increasing more than ever.

The present invention has been made in view of the above circumstances, and the problem to be solved is to provide a coating device capable of forming a coating film with excellent smoothness compared to conventional coating devices.

A coating device of the present invention is a coating device for coating a substrate with a coating material, and includes a coating roll, a doctor roll, and a receiving member. In the coating apparatus of the present invention, a liquid pool is formed by the receiving member, the coating roll and the doctor roll so that the coating material adheres to the coating roll and the doctor roll.

In the coating apparatus of the present invention, the coating roll and the doctor roll are formed with liquid pools so that the coating material adheres, so the amount of coating material adhering to the coating roll is stabilized and a smooth coating film is formed on the substrate. can do.

The perspective view which shows an example of the coating device of this invention. FIG. 2 is an explanatory diagram of a coating roll, a doctor roll, and a receiving member of the coating apparatus of FIG. 1; (a) is an explanatory diagram showing an example of a holder, and (b) is an explanatory diagram showing another example of the holder. FIG. 4 is an explanatory diagram showing an example of a case where a base material is moved by roll-to-roll; FIG. 4 is an explanatory diagram showing an example of a case where a doctor roll is provided at a position lower than the coating roll; FIG. 4 is an explanatory diagram showing an example of a case where a coating roll, a doctor roll, and a receiving member are provided at different heights; 4A to 4D are front views for explaining an example of the operation of the coating device shown in FIG. 1; FIG. 4A to 4D are side views for explaining an example of the operation of the coating device shown in FIG. 1; FIG. 5A and 5B are front views for explaining an example of the operation of the coating device shown in FIG. 4; FIG. 5A and 5B are side views for explaining an example of the operation of the coating device shown in FIG. 4; FIG.

(Embodiment 1)
An example of an embodiment of a coating device of the present invention will be described with reference to the drawings. As an example, the coating device shown in FIG. 1 is a device for coating a substrate P with a coating material, and includes a coating roll 1, a doctor roll 2, and a receiving member 3. As shown in FIG. In this embodiment, a liquid pool 4 is formed by the receiving member 3 , the application roll 1 and the doctor roll 2 so that the paint adheres to the application roll 1 and the doctor roll 2 . Spill stoppers 5 are provided on both outer sides in the longitudinal direction of the coating roll 1 and the doctor roll 2 to prevent the paint pooled in the liquid pool portion 4 from spilling. As shown in FIG. 2, the application roll 1, the doctor roll 2 and the receiving member 3 are provided on both sides of the base material P at the same height.

The coating roll 1 is a member for transferring a coating material to the substrate P to form a coating film. The coating roll 1 may be a rubber roll, a metal roll, or a roll having a DLC film on its outer periphery. Rubber rolls include natural rubber and synthetic rubber. Metal rolls include those plated on carbon steel.

In this embodiment, a solid roll having no irregularities (cells) on the outer peripheral surface is used as the coating roll 1. In addition to the solid roll, the coating roll 1 may have various shapes such as spiral grooves, single grooves, and dots on the outer peripheral surface. Engraved rolls provided with a can also be used. The shape of the cell is an example and may be other than this.

The coating roll 1 of this embodiment is configured to always rotate regardless of whether it is in contact with the substrate P or not. The coating rolls 1 move in the opposite direction to the moving direction of the base material P, specifically, as shown in FIG. A roll 1 is arranged to rotate counterclockwise. The coating roll 1 may rotate in the opposite direction (positive direction with respect to the moving direction of the substrate P). In either case, it is configured to rotate in the direction opposite to the direction of rotation of the doctor roll 2 with which it comes into contact.

The doctor roll 2 is a member for supplying the paint to the coating roll 1 and smoothing (smoothing) the paint on the surface of the coating roll 1 . The doctor roll 2 may be a metal roll, a rubber roll, or a roll having a DLC film on its outer periphery. Rubber rolls include natural rubber and synthetic rubber. Metal rolls include those plated on carbon steel.

In this embodiment, as the doctor roll 2, a metal roll made of carbon steel and having a DLC film on its outer periphery is used. Although not shown, the outer peripheral surface of the doctor roll 2 is provided with irregularities (cells) of various shapes such as spiral grooves, single grooves, and dots. The shape of the cell is an example and may be other than this. A beta roll without cells can also be used for the doctor roll 2 .

In this embodiment, the applicator roll 1 and the doctor roll 2 have the same diameter and length. The coating roll 1 and the doctor roll 2 may have different diameters and lengths. However, the doctor roll 2 preferably has a diameter larger than that of the coating roll 1 . By using the doctor roll 2 having a diameter larger than that of the coating roll 1, the coated portion of the doctor roll 2 is always in contact with the coating roll 1 while the coating roll 1 makes one turn. Makes it easier to evenly distribute the paint on the surface.

The receiving member 3 is a member that forms a liquid pool portion 4 between the coating roll 1 and the doctor roll 2 . The receiving member 3 of this embodiment is a flat plate member longer than the coating roll 1 and doctor roll 2 . The receiving member 3 can be made of metal, resin, rubber, or the like.

As shown in FIG. 2, the receiving member 3 of this embodiment is sized to extend over both the coating roll 1 and the doctor roll 2 . The receiving member 3 has an angle formed by the imaginary axis line (indicated by a two-dot chain line in FIG. 2) parallel to the straight line in the moving direction of the substrate P moving vertically and the lower end side of the receiving member 3. It is obliquely provided so that α is about 40 degrees. This angle can be adjusted as appropriate.

In this embodiment, the coating roll 1 and the doctor roll 2 are in contact with each other, and the coating roll 1 and the receiving member 3 are in contact with each other. Specifically, a liquid pool 4 is formed between the receiving member 3 and the coating roll 1 and the doctor roll 2, and the paint pooled in the liquid pool 4 adheres to both the coating roll 1 and the doctor roll 2. I'm trying to do it.

As in this embodiment, when the paint pooled in the liquid pool 4 directly adheres to the coating roll 1, the coating roll 1 itself can pick up the paint, so the amount of paint transferred from the doctor roll 2 is Even when there is a small amount of the coating material, uneven coating of the coating material on the base material P is unlikely to occur, and a smooth coating film can be formed on the surface of the base material P.

In this embodiment, the doctor roll 2 is arranged outside and higher than the applicator roll 1 . Such a positional relationship has the advantage that the paint adhering to the coating roll 1 does not fall off due to gravity, and the paint can be reliably transferred to the substrate P. In addition, since the distance from the point of contact with the doctor roll 2 to the base material P is shortened, there is an advantage that even in the case of applying volatile paint, it can be transferred to the base material P before it evaporates. .

The coating apparatus of this embodiment includes a coating roll 1 , a doctor roll 2 and a receiving member 3 , as well as a holder 6 , a lower receiver 7 , a pressing pin 8 and an attitude holder 9 . Note that the holder 6, the lower receiver 7, the pressing pin 8, and the attitude holder 9 may be provided as required, and any of them can be omitted or replaced by other means.

The holder 6 is a member that holds the substrate P and moves it in the vertical direction. The holder 6 of this embodiment is a clip-shaped member that clamps the upper portion of the substrate P. As shown in FIG. The holder 6 is configured to be raised and lowered by a lifting device (not shown). As shown in FIGS. 1 and 3(a), in this embodiment, the case where there are three holders 6 is taken as an example, but the number of holders 6 may be more or less than three.

When holding a soft base material such as a flexible substrate, in order to prevent the base material P from wobbling, it is recommended to use holders 6 that hold both ends of the base material P in the width direction as shown in FIG. 3(b). can also The holder 6 has a length that can hold the base material P over its entire length or substantially its entire length. Anything other than these can also be used for the holder 6 .

The lower receiver 7 is a member that supports from below the substrate P that has been lowered to a predetermined position. In this embodiment, an upward U-shaped gutter-shaped member longer than the width direction of the substrate P is used as the lower receiving member 7 . The lower receiving member 7 is arranged at a position lower than the coating roll 1, the attitude holder 9, and the pressing pin 8. As shown in FIG. The lower receiving tool 7 is provided at a position such that the vicinity of the upper end of the base material P reaches the same height as the coating roll 1 when the base material P reaches the lower receiving tool 7 .

The pressing pin 8 is a pin-shaped member that temporarily presses both sides of the substrate P that has been lowered to a predetermined position. The pressing pin 8 of this embodiment is configured to move in a direction approaching the base material P and a direction away from the base material P by driving means (not shown). In this embodiment, two pins are provided outside each surface of the substrate P (four pins in total), but the number of the pressing pins 8 may be more or less than four.

The posture holder 9 is a member for holding the upright posture of the base material P by contacting or adjoining both surfaces of the base material P. As shown in FIG. The posture holder 9 of this embodiment is a rectangular parallelepiped block made of rubber. In this embodiment, two attitude holders 9 are provided outside one surface of the base material P and two outside the other surface (four in total). As shown in FIGS. 3(a) and 3(b), the posture holders 9 on the outside of each surface are provided at intervals in the width direction of the substrate P. As shown in FIGS. The number of posture holders 9 can be more or less than four.

Each posture holder 9 of this embodiment is configured to move in a direction approaching the base material P and a direction away from the base material P by driving means (not shown). Although each attitude holder 9 can be configured to move individually, in this embodiment, two attitude holders 9 holding the same surface of the base material P are moved synchronously.

In this embodiment, the attitude holder 9 is moved separately from the coating roll 1, the doctor roll 2 and the receiving member 3, but the attitude holder 9 moves synchronously with the coating roll 1, the doctor roll 2 and the receiving member 3. You can also move by Each attitude holder 9 can also be fixed at a fixed position without moving.

Each posture holder 9 is provided below the coating roll 1 . The posture holder 9 can be provided so as to contact the coating roll 1 or can be provided separately. When provided so as to be in contact with the application roll 1 , the upper surface of the posture holder 9 may be recessed in an arc shape along the outer periphery of the application roll 1 .

Although the posture holder 9 is made of rubber in this embodiment, the posture holder 9 may be made of a material other than rubber. In any case, it is preferable to use a material with low frictional resistance to the extent that smooth movement (lifting and lowering) of the base material P is not hindered when the paint is applied by the coating roll 1 . The posture holder 9 may have a shape with a small contact area so as not to hinder the smooth rise of the substrate P. Further, at least the contact surface of the posture holder 9 may be treated with fluorine resin to reduce frictional resistance.

In this embodiment, the case where the paint is applied while raising the base material P is taken as an example, but as shown by the dashed line in FIG. You can also In this case as well, the coating roll 1 may rotate in the direction opposite to the moving direction of the substrate P, or may rotate in the forward direction relative to the moving direction of the substrate P.

(Embodiment 2)
Another example of the embodiment of the coating apparatus of the present invention will be described with reference to the drawings. The basic configuration of the coating device of this embodiment is the same as that of the first embodiment. What is different is the method of moving the substrate P. In the above-described embodiment, the case where the base material P is held by the holder 6 and moved in the vertical direction (when the base material P is a sheet) is taken as an example. The paint can also be applied to the base material P that moves in a roll-to-roll manner.

Specifically, as shown in FIG. 4 , a delivery roll 10 and a take-up roll 11 are arranged with an interval in the vertical direction, and the substrate P is delivered from the delivery roll 10 and wound up by the take-up roll 11. can be made

In the example shown in FIG. 4, a case is shown in which the delivery roll 10 is provided on the lower side and the winding roll 11 is provided on the upper side. It is also possible to apply the paint while moving the material P downward as indicated by the dashed line in FIG.

4, the applicator roll 1, the doctor roll 2 and the receiving member 3 can be the same as those in the first embodiment. When the base material P is moved by the roll-to-roll method, the holder 6, the lower support 7, the pressing pin 8, and the attitude holder 9 can be omitted.

(Other embodiments)
In both of the above-described embodiments, the application roll 1 and the doctor roll 2 have the same diameter as an example, but the application roll 1 and the doctor roll 2 may have different diameters. In the above-described embodiment, the application roll 1 and the doctor roll 2 have the same length as an example, but the application roll 1 and the doctor roll 2 may have different lengths.

In the above-described two embodiments, a case where a solid roll is used as the coating roll 1 and an engraved roll as the doctor roll 2 is taken as an example. Also, if possible, both the coating roll 1 and the doctor roll 2 may be solid rolls or engraved rolls.

In both of the above embodiments, a rubber roll is used as the coating roll 1, and a metal roll (a DLC film formed on carbon steel) is used as the doctor roll 2. The metal roll is used as the coating roll 1, and the doctor roll A rubber roll can also be used as 2 . If possible, both the application roll 1 and the doctor roll 2 may be metal rolls or rubber rolls.

Metal rolls include, for example, SUS304, SUS440C, and other austenitic and martensitic stainless steels in general; carbon steel surfaces such as STKM13A and S25C; A material on which a DLC film is applied, or the like can be used.

In both of the above-described embodiments, the case where the doctor roll 2 is arranged at a position higher than the application roll 1 is taken as an example, but the doctor roll 2 is positioned lower than the application roll 1 (lower position) as shown in FIG. ) can also be placed in In this case, the doctor roll 2 located on the left side of the substrate P in the figure rotates clockwise, and the coating roll 1 rotates counterclockwise. On the other hand, the doctor roll 2 located on the right side of the substrate P in the figure rotates counterclockwise, and the coating roll 1 rotates clockwise. This configuration is easy to adopt when the viscosity of the paint is high enough not to drop due to gravity.

Although not described in the above-described embodiments, the doctor roll 2 can be moved in the direction in which the coating roll 1 is pushed in and in the direction opposite to that direction (the direction in which the pushing is released). Similarly, the application roll 1 can be configured to be movable in a direction in which the substrate P is pushed and in a direction opposite to that direction (a direction in which the pushing is released).

In the above-described two embodiments, the coating roll 1, the doctor roll 2 and the receiving member 3 are provided on both sides of the substrate P at the same height. The members 3 can also be provided at different heights on both sides of the substrate P, as shown in FIG. This configuration is easy to adopt when the substrate P is a soft material such as a film or copper foil.

In both of the above-described embodiments, the spill stoppers 5 are provided on both longitudinal outer sides of the application roll 1 and the doctor roll 2, but by adding a structure corresponding to the spill stoppers 5 to the receiving member 3, The spill stop 5 can also be omitted.

The present invention is not limited to the structures and shapes of the above-described embodiments, and various modifications and changes are possible without departing from the gist of the present invention.

Next, the operation of the coating apparatus of the present invention will be described with reference to the drawings. Here, as an example of the operation of the coating device of the present invention, the operation of the coating device of the first embodiment and the operation of the coating device of the second embodiment will be described.

The coating apparatus of Embodiment 1 operates as follows. 7(a) to (d) and FIGS. 8(a) to (d), the states of the holders 6, the pressing pins 8 and the attitude holders 9 in contact with or close to the substrate P are indicated by solid lines. The state of not contacting or not approaching the substrate P is indicated by a two-dot chain line.
(1) The substrate P held by the holder 6 is set at a predetermined position (FIGS. 7(a) and 8(a)).
(2) The substrate P held by the holder 6 descends to a predetermined position and is supported by the lower receiver 7 (FIGS. 7(b) and 8(b)).
(3) Pressing pins 8 are brought into contact with both sides of the substrate P to hold the substrate P (FIGS. 7(c) and 8(c)). At this time, the clamping of the substrate P by the holders 6 is released immediately before the substrate P is held by the pressing pins 8 . In addition, the attitude holder 9 approaches or contacts both surfaces of the base material P, and the upright attitude of the base material P is maintained.
(4) The coating rolls 1 on both sides of the base material P are brought into contact with the base material P, and the paint held on the surface of the coating rolls 1 is transferred to the base material P (FIGS. 7(d) and 8(d). ). At this time, the upper end portion of the base material P is held again by the holders 6 and the base material P is lifted up, and the paint on the surface of the coating roll 1 is transferred to the base material P which is lifted up. Incidentally, just before the application roll 1 contacts the substrate P, the holding of the substrate P by the pressing pins 8 is released.

The coating apparatus of Embodiment 2 operates as follows.
(1) The base material P held by the delivery roll 10 and the take-up roll 11 is set at a predetermined position (Fig. 9(a), Fig. 10(a)).
(2) The paint held on the surface of the coating roll 1 with the coating roll 1 in contact with both surfaces of the base material P that moves from the side of the delivery roll 10 to the side of the winding roll 11 by the operation of the delivery roll 10 and the winding roll 11. is transferred to the substrate P (FIGS. 9(b) and 10(b)).

In both of the above operations, the paint applied to the base material P from the coating roll 1 is the paint supplied from the doctor roll 2 and the paint picked up by the coating roll 1 itself, and the paint has a predetermined thickness when passing through both rolls. is averaged to

As described above, in the coating apparatus of each of the above embodiments, not only is the coating material supplied from the doctor roll 2 to the coating roll 1, but also the coating roll 1 can pick up the coating material by itself. The amount of paint adhering to the substrate P tends to be stable, and a smooth coating film can be formed on the substrate P.

The coating apparatus of the present invention can be used to apply paint to various base materials P, particularly when applying a resist to a printed wiring board such as a rigid board or a flexible board, or when applying an adhesive to a copper foil. etc. can be suitably used.

REFERENCE SIGNS LIST 1 application roll 2 doctor roll 3 receiving member 4 liquid pool 5 spill stopper 6 holding tool 7 lower receiving tool 8 pressing pin 9 posture holding tool 10 delivery roll 11 winding roll P base material

Claims (12)

In a coating device that applies a coating material to a base material,
Equipped with a coating roll, a doctor roll and a receiving member,
A liquid pool is formed by the receiving member, the coating roll and the doctor roll so that the coating material adheres to the coating roll and the doctor roll.
A coating device characterized by: In the coating device according to claim 1,
The receiving member is arranged outside the coating roll and the doctor roll,
A coating device characterized by: In the coating device according to claim 1 or claim 2,
The applicator roll rotates in the direction opposite to the direction of rotation of the doctor roll,
A coating device characterized by: In the coating device according to any one of claims 1 to 3,
The rotation speed of the coating roll and the doctor roll are different,
A coating device characterized by: In the coating device according to any one of claims 1 to 4,
the applicator roll rotates in the forward or reverse direction relative to the direction of movement of the substrate;
A coating device characterized by: In the coating device according to any one of claims 1 to 5,
The doctor roll can move in the direction of pushing the coating roll and the direction of releasing the pushing.
A coating device characterized by: In the coating device according to any one of claims 1 to 6,
The coating roll is movable in the direction of pushing the substrate and the direction of releasing the pushing,
A coating device characterized by: In the coating device according to any one of claims 1 to 7,
A coating roll, a doctor roll, and a receiving member are provided on both sides of the substrate,
A coating device characterized by: In the coating device according to claim 8,
The coating roll, the doctor roll and the receiving member provided on both sides of the substrate are provided at the same height or different heights in the vertical direction,
A coating device characterized by: In the coating device according to any one of claims 1 to 9,
Equipped with a holder that can move the held base material in the vertical direction,
A coating device characterized by: In the coating device according to any one of claims 1 to 9,
Equipped with a feed roll and a take-up roll that are spaced apart in the vertical direction,
The substrate is unwound from the pay-out roll and wound up by the take-up roll.
A coating device characterized by: In the coating device according to any one of claims 1 to 11,
A posture holder for holding the posture of the base material is provided below the coating roll, the doctor roll, and the receiving member,
A coating device characterized by:

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