JPH09108600A - Roll coater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent unevenness in the thickness, in the form of a stripe, from being produced in a coated liquid film applied onto the surface of a base plate by supporting at least one roll of a coating liquid feed roll unit so as to be movable back and force in the axial direction thereof and by providing a straight line moving means for moving the roll back and forth along a straight line. SOLUTION: If a drive motor 20 for rotating a roll is actuated, the driving force is transmitted from a drive gear 28 to a driven gear 18 to rotate a roll 10 being an offset roll. At the same time, if a roll straight drive motor 42 is actuated, a link rod 40 is moved upward and downward following the rotation of a rotation disk 46 to move a cam follower 34 right and left through an L-shaped link plate 36 so that the roll 10 is moved back and forth along a straight line. Thus, if the roll 10 moves back and forth in an axial direction, even if a stripe-shaped unevenness is produced in a direction perpendicular to the axial direction in a resist liquid film attached, in the form of a film, to the periphery of a pickup roll, the stripe-shaped unevenness can be eliminated by the movement of the roll 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass substrate for liquid crystals, a substrate for film liquid crystals, a substrate for image sensors, a substrate for printed wirings, a semiconductor wafer, and various other substrates in a horizontal direction while the applicator roll is used as a substrate. By contacting and rotating the surface of the applicator roll, a coating liquid, such as a photoresist liquid or a polyimide resin, is applied to the substrate surface through the peripheral surface of the applicator roll to form a coating film having a predetermined film thickness on the substrate surface. It relates to a roll coater used for forming.

[0002]

2. Description of the Related Art In this type of roll coater, a substrate is transported by a plurality of transport rolls arranged in parallel along a horizontal transport path, and the substrate is fed between an applicator roll and a backup roll below it. Alternatively, the substrate is held and conveyed on the upper surface of the stage which is arranged so as to be linearly movable in the horizontal direction, and the substrate is sent to the position below the applicator roll, and the coating liquid supply roll or a coating consisting of a plurality of rolls is applied. By rotating the coating liquid supplied to the peripheral surface of the applicator roll through the liquid supply roll unit in the conveying direction of the substrate or in the opposite direction while the applicator roll makes the peripheral surface contact the surface of the substrate. After coating on the surface of the substrate, the coating liquid applied on the surface of the substrate is dried to form a coating film having a predetermined film thickness on the surface of the substrate.

[0003]

By the way, in the conventional roll coater, due to the uneven viscosity of the coating liquid,
Due to the effect of so-called "ridges" peculiar to the roll coater, the coating liquid film adhered to the peripheral surface of the coating liquid supply roll or each roll of the coating liquid supply roll unit in a film form, and therefore, is transferred. The coating liquid film adhered to the peripheral surface of the applicator roll in some cases had streaky unevenness in the circumferential direction orthogonal to the axial direction of the roll. Then, when the coating liquid film is transferred from the peripheral surface of the applicator roll to the surface of the substrate, the coating liquid film deposited on the surface of the substrate,
There has been a problem that streak-shaped film thickness unevenness appears along the substrate transport direction.

The present invention has been made in view of the above circumstances, and eliminates the effects of uneven viscosity of the coating liquid and "waviness" peculiar to the roll coater, and adheres to the peripheral surface of the applicator roll. Provided is a roll coater capable of preventing streaky unevenness in the circumferential direction from occurring in a coating liquid film and preventing streak-like thickness unevenness from appearing in a coating liquid film deposited on a surface of a substrate. The purpose is to

[0005]

The invention according to claim 1 is
At least one roll of a coating liquid supply roll for supplying the coating liquid to the peripheral surface of the applicator roll or a coating liquid supply roll unit consisting of a plurality of rolls,
It is characterized in that it is provided with a linear moving means for supporting the roll so as to be reciprocally movable in the axial direction and linearly reciprocating the roll.

According to a second aspect of the present invention, in the roll coater according to the first aspect, the linear moving means is engaged with a groove cam fixed to a rotary shaft of a roll and a groove of the groove cam. It is characterized by being configured with a cam follower.

According to a third aspect of the present invention, in the roll coater according to the second aspect, as the groove cam, one having a groove formed in a circumferential direction orthogonal to the rotation supporting shaft of the roll is used. The cam follower is attached to one end of an L-shaped link plate that is L-shaped and rotates about a bent portion as a fulcrum, and the other end of the L-shaped link plate is pivotally attached to one end of a link member, and the link is formed. The other end portion of the member is pivotally attached to an eccentric position of a rotary disc fixed to the rotary shaft of the drive motor to form a linear moving means.

In the roll coater of the invention according to claim 1,
For a coating liquid supply roll or a roll having a coating liquid supply roll unit composed of a plurality of rolls, at least one roll of them is used for supplying the coating liquid while being reciprocally moved in the axial direction by the linear movement means. The coating liquid is supplied from the roll or the roll unit for supplying the coating liquid to the peripheral surface of the applicator roll. Therefore, in any roll of the coating liquid supply roll or the coating liquid supply roll unit, streak-like unevenness in the circumferential direction orthogonal to the axial direction of the roll occurs in the coating liquid film adhered to the peripheral surface in a film shape. Even if the adjacent rolls relatively move in the axial direction, the streaky unevenness in the circumferential direction is eliminated. Further, thin streak-like unevenness that occurs at the transfer site when the coating liquid film is transferred from a roll to an adjacent roll is immediately eliminated by the relative movement of the adjacent rolls in the axial direction. Therefore, the coating liquid film attached to the peripheral surface of the applicator roll does not have streaky unevenness in the circumferential direction, and the coating liquid film adhered to the surface of the substrate has streaky film thickness unevenness. It disappears.

In the roll coater of the invention according to claim 2,
The rotary motion is converted into a linear reciprocating motion of the roll by the groove cam fixed to the rotary shaft and the cam follower engaged with the groove of the groove cam.

In the roll coater of the invention according to claim 3,
When the drive motor is driven, the rotating disc fixed to the rotating shaft rotates, and one end of the link member, the other end of which is attached to the eccentric position of the rotating disc, rotates with the rotation of the rotating disc. The L-shaped link plate having the other end pivotally attached to the link member swings as the link member reciprocates, and the cam follower attached to one end of the L-shaped link plate has a groove. By reciprocating while engaging with the groove of the cam, the rotary support shaft of the roll to which the groove cam is fixed reciprocates in the axial direction.

[0011]

Preferred embodiments of the present invention will be described below with reference to the drawings.

First, FIG. 4 is a perspective view showing a schematic structure of a roll coater. This roll coater comprises an applicator roll 2, an offset roll 4 and a pick-up roll 6, and a coating liquid supply roll unit. The liquid storage tank 8 constitutes a coating liquid supply system. Although not shown in the drawings, the lower side of the coating liquid supply system is composed of a plurality of transfer rolls arranged in parallel in the horizontal direction and a backup roll arranged directly below the applicator roll 2. A substrate transfer system is provided. Instead of a substrate transport system composed of a plurality of transport rolls and a backup roll, a stage is arranged so as to be linearly reciprocally movable in the horizontal direction, and the substrate is held on the upper surface of the stage by suction or the like. The substrate transfer system may be configured so that the transfer is performed in a single manner.
This substrate transfer system is not directly related to the gist of the present invention, and therefore further description is omitted.

The entire coating liquid supply system is supported so as to be vertically movable. In this coating liquid supply system,
A coating liquid, for example, a photoresist liquid (hereinafter referred to as “resist liquid”) is stored in the liquid storage tank 8, and a part of the peripheral surface of the pickup roll 6 is dipped in the resist liquid in the liquid storage tank 8. Has been done. The pickup roll 6 is rotationally driven around the horizontal axis in the direction of the arrow at a constant speed by a motor (not shown) to scrape up the resist liquid from the liquid storage tank 8 and deposit it in a film form on the peripheral surface. The offset roll 4 is rotationally driven around the horizontal axis in the direction of the arrow at a constant speed, and the pickup roll 6 can freely come into contact with and separate from the offset roll 4 so that the gap size can be adjusted.
An appropriate amount of the resist liquid adhered in a film form on the peripheral surface of is transferred to the peripheral surface of the offset roll 4. The peripheral surface of the applicator roll 2 is in contact with the peripheral surface of the offset roll 4, and the applicator roll 2 is rotationally driven around the horizontal axis in the direction of the arrow at a constant speed by a motor (not shown) to be transferred to the peripheral surface of the offset roll 4. The resist solution adhered in the form of a film is retransferred to the peripheral surface of the applicator roll 2. The illustrated example is a so-called reverse coating type roll coater in which the applicator roll 2 is rotated in the direction opposite to the substrate W transport direction, but the applicator roll 2 is rotated in the substrate W transport direction. The method may be any of the above.

The substrate W is horizontally transported at a constant speed by the substrate transport system, and when the front end of the substrate W approaches the backup roll and reaches a predetermined coating start position, the coating liquid supply system descends. The peripheral surface of the applicator roll 2 contacts the surface of the substrate W, and the substrate W is conveyed forward through the gap between the applicator roll 2 and the backup roll. During this time, the resist liquid transferred to the peripheral surface of the applicator roll 2 and adhered in the form of a film is transferred from the peripheral surface of the applicator roll 2 to the surface of the substrate W,
A resist film having a predetermined thickness is deposited on the surface of the.

The structure described above is not different from the conventional roll coater, but in this roll coater, at least one of the coating liquid supplying roll units for supplying the coating liquid to the peripheral surface of the applicator roll 2 is used. The book roll, which is the offset roll 4 in the example shown in FIG. 4, is supported so as to be reciprocally movable in the axial direction, and is linearly reciprocally moved while rotating in the arrow direction. An example of a drive mechanism that reciprocates in the axial direction while rotating the roll will be described with reference to FIGS. 1 to 3.

In the drive mechanism shown in FIG. 1 which is a schematic sectional view of a part of which is shown in cross section, and in FIG. 2 which is a schematic side view when viewed from the right side, the roll 10 corresponds to the offset roll 4 of FIG. The rotary support shafts 12 on both sides of the roll 10,
The bearings 14 and 16 fixed to a fixed portion (not shown) of the roll coater are rotatably supported around the axis and slidably in the axial direction. A driven gear 18 having a small tooth width is fixed to one of the rotary support shafts 12. Further, a drive shaft 26 connected to a rotary shaft 22 of a roller rotation drive motor 20 fixed to a fixed portion via a coupling 24, and a drive gear 28 having a large tooth width dimension.
Is fixed. Then, the drive gear 28 and the driven gear 1
8 meshes with each other in such a manner that their tooth surfaces are slidably contactable in the axial direction. The tooth width of the drive gear 28 is set to such a dimension that the driven gear 18 does not separate from the drive gear 28 when the driven gear 18 reciprocates in the axial direction.

Further, a groove cam 30 having a groove 32 formed in a circumferential direction orthogonal thereto is fixed to the other rotary support shaft 14, and a cam follower 34 slides on the inner surface of the groove 32 of the groove cam 30. Engagement is possible. Cam follower 34
L has an L shape and rotates about a bent portion as a fulcrum 38.
It is attached to one end of the letter-shaped link plate 36. The other end of the L-shaped link plate 36 is pivotally attached to one end of the link rod 40, and the other end of the link rod 40 is fixed to the rotary shaft 44 of the roll linear drive motor 42. Is eccentrically mounted.

In the drive mechanism shown in FIGS. 1 and 2, when the roll rotation drive motor 20 is driven, the rotational drive force is transmitted from the drive gear 28 to the driven gear 18, and the driven gear 18 rotates. By rotating together with 12, the roll 10 is rotated. At the same time, when the roll direct drive motor 42 is driven, the rotary disc 46 fixed to the rotary shaft 44 thereof rotates, and the link rod 40 reciprocates in the vertical direction as the rotary disc 46 rotates. Move. Further, as the link rod 40 reciprocates, the L-shaped link plate 36
Swings around a fulcrum 38, and the cam follower 34 attached to one end of the L-shaped link plate 36 moves the groove 32 of the groove cam 30.
The groove cam 30 reciprocates in the axial direction integrally with the rotation support shaft 14 in such a manner that the roll 10 is linearly reciprocated. At this time, the rotation support shafts 12 and 14 of the roll 10 rotate about the axis and reciprocate linearly in the axial direction,
The driven gear 18 slides in the axial direction with respect to the drive gear 28 while the driving gear 28 and the driven gear 18 mesh with each other and rotate, and the groove cam 30 engages with the cam follower 34 to axially move the driven gear 18. While reciprocating, the inner surface of the groove 32 is brought into sliding contact with the cam follower 34 to rotate.

In the mechanism shown in FIGS. 1 and 2, by changing the axial attachment positions of the link rod 40 and the L-shaped link plate 36 and the axial attachment positions of the link rod 40 and the rotary disc 46,
The reciprocating movement distance of the roll 10 in the axial direction can be adjusted.

Next, in another example of the drive mechanism shown in the schematic configuration diagram of FIG.
Corresponding to the offset roll 4, and the rotary shafts 52 and 54 on both sides of the roll 50 are supported by bearings 56 and 56, respectively, so as to be rotatable about the axis and slidable in the axial direction.
One end of the rotary support shaft 52 is machined into the spline shaft 58, and the groove cam 68 is fixed to the other rotary support shaft 54. The spline shaft 58 of one of the rotary support shafts 52 is slidable in the axial direction and has an axial center line on a connecting cylindrical member 60 having a boss hole 62 in which a key groove corresponding to a key integrally formed with the spline shaft 58 is formed. It is engaged so as to rotate together with the connecting cylindrical member 60. The rotary shaft 66 of the drive motor 64 is fixed to the connecting cylindrical member 60 with their axes aligned. In addition, the other rotation support shaft 54
An endless groove 70 is formed on the outer peripheral surface of the groove cam 68 fixedly attached to the groove cam 68 so as to be inclined with respect to the circumferential direction orthogonal to the axis. The cam follower 72 is engaged with the groove 70 of the groove cam 68, and the cam follower 72 is fixed to the fixed portion of the device.

In the drive mechanism shown in FIG. 3, the drive motor 6
4 is driven, the rotational driving force thereof is applied to the connecting cylindrical member 6
The roll 50 is rotated by being transmitted from 0 to the spline shaft 58 and rotating the rotation support shaft 52. Then, the rotation support shaft 54 rotates integrally with the roll 50, and the groove cam 68 fixed to the rotation support shaft 54 also rotates. Groove cam 68
When is rotated, the groove cam 68 slides the inner surface of the groove 70 against the fixed cam follower 72 and reciprocates in the axial direction. At this time, the spline shaft 5 of the rotary support shaft 52
8, the spline shaft 58 slides in the axial direction with respect to the connecting cylinder member 60 while engaging with each other and rotating integrally.

The drive mechanism for reciprocating the roll in the axial direction while rotating the roll is not limited to the structure shown in FIGS. 1, 2 and 3, and various structures can be used.

In the roll coater shown in FIG.
The offset roll 4 is reciprocated in the axial direction while being rotated around its axis by the drive mechanism shown in FIG. 2 or 3. For this reason, even if the resist liquid film that is picked up from the liquid storage tank 8 and adheres to the peripheral surface of the pick-up roll 6 in a film shape has streaky unevenness in the circumferential direction orthogonal to the axial direction, , The circumferential streak-like unevenness disappears with the reciprocating movement in the axial direction. Further, the thin streak-like unevenness generated at the transfer portion when the resist liquid film is transferred from the roll to the adjacent roll is immediately eliminated by the relative movement of the adjacent rolls in the axial direction. Therefore, the resist liquid film transferred from the peripheral surface of the offset roll 4 to the peripheral surface of the applicator roll 2 and adhered to the peripheral surface of the applicator roll 2 in the form of a film may have streaky unevenness in the circumferential direction. Therefore, in the resist film transferred from the peripheral surface of the applicator roll 2 to the surface of the substrate W and applied to the surface of the substrate W, streak-like thickness unevenness along the transport direction of the substrate W appears. There is no such thing.

The coating liquid supply system of the roll coater shown in FIG. 4 comprises three rolls of an applicator roll 2, an offset roll 4 and a pickup roll 6, which constitutes the coating liquid supply system. The present invention can be applied as long as the number of rolled rolls is two or more including the applicator roll. For example, like the roll coater shown in FIG. 5, the coating liquid supply system includes an applicator roll 74, a coating liquid supply roll (pickup roll) 76, and a liquid storage tank 78.
Alternatively, the coating liquid supply roll 76 may be reciprocally moved in the axial direction while being rotated about its axis. Also, like the roll coater shown in FIG.
The coating liquid supply system includes an applicator roll 80, a coating liquid supply roll unit including an offset roll 82, a pickup roll 84, and a squeegee roll 86, and a liquid storage tank 88. At least one roll, in the illustrated example, the pickup roll 84 may be reciprocally moved in the axial direction while being rotated around its axis. 5 and 6
Here, the illustration of the substrate transfer system is omitted as in FIG.

[0025]

When the roll coater of the invention according to claim 1 is used to apply the coating liquid to the surface of the substrate, the viscosity unevenness of the coating liquid and the "waviness" peculiar to the roll coater are obtained.
It is possible to eliminate the influence of the above and prevent the appearance of streak-like thickness unevenness in the coating liquid film deposited on the surface of the substrate.
The quality of the coating film can be improved.

In the roll coater of the invention according to claim 2,
With the combination of the groove cam and the cam follower, the roll can be linearly reciprocated while rotating, and the above effect of the invention according to claim 1 can be obtained.

In the roll coater of the invention according to claim 3,
A drive motor is used separately from the drive motor for rotating the roll, and the rotational motion of the drive motor can be converted into a linear reciprocating motion to linearly reciprocate the rotating roll. It is possible to achieve the above effects.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an example of a drive mechanism that reciprocates in the axial direction while rotating a roll, a part of which is shown in cross section.

FIG. 2 is a schematic side view of the drive mechanism shown in FIG. 1 as viewed from the right side.

FIG. 3 is a schematic configuration diagram showing another example of a drive mechanism that reciprocates in the axial direction while rotating a roll, and a part of which is shown in cross section.

FIG. 4 is a perspective view showing an example of a schematic configuration of a roll coater according to the present invention.

FIG. 5 is a perspective view showing another example of the schematic configuration of the roll coater according to the present invention.

FIG. 6 is a perspective view showing still another example of the schematic configuration of the roll coater according to the present invention.

[Explanation of symbols]

 2, 74, 80 Applicator roll 4, 82 Offset roll 6, 84 Pick-up roll 8, 78, 88 Storage tank 10, 50 roll 12, 14, 52, 54 Roll rotation spindle 16, 56 Bearing 18 Driven gear 20 Roll rotation drive motor 28 Drive gear 30, 68 Groove cam 32, 70 Groove cam groove 34, 72 Cam follower 36 L-shaped link plate 38 L-shaped link plate fulcrum 40 Link rod 42 Roll direct drive motor 44 Rotation of drive motor Shaft 46 Rotating Plate 58 Spline Shaft 60 Coupling Cylindrical Member Having Boss Hole 64 Drive Motor 76 Coating Liquid Supply Roll (Pickup Roll) 86 Squeegee Roll W Substrate

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Yoshito Ishizaki Inventor Yoshihito Ishizaki 1 480 Takamiya-cho, Hikone City, Shiga Dai Nippon Screen Mfg. Co., Ltd. Hikone District Office (72) Inventor Yasuyuki Kurisu 1-chome Kamisakabe, Amagasaki City, Hyogo 2-1 No. 1 in Optrex Co., Ltd. Amagasaki factory

Claims (3)

[Claims] 1. An applicator roll, the peripheral surface of which is brought into contact with the surface of a substrate conveyed in the horizontal direction to transfer the coating liquid from the peripheral surface to the surface of the substrate, and the coating liquid is supplied to the peripheral surface of the applicator roll. A roll coater comprising a coating liquid supply roll or a coating liquid supply roll unit composed of a plurality of rolls, wherein at least one roll of the coating liquid supply roll or the coating liquid supply roll unit is A roll coater, which is provided with a linear moving means that supports the roll so as to be reciprocally movable in the axial direction and linearly reciprocates the roll. 2. The roll coater according to claim 1, wherein the linear moving means includes a groove cam fixed to a rotation shaft of the roll and a cam follower engaging with the groove of the groove cam. 3. The groove cam has a groove formed in a circumferential direction orthogonal to the rotation supporting shaft of the roll, and the cam follower has one end of an L-shaped link plate which is L-shaped and rotates about a bending portion as a fulcrum. Eccentric position of a rotary disc fixed to the drive shaft and the other end of the L-shaped link plate is pivotally attached to one end of the link member, and the other end of the link member is fixed to the rotary shaft of the drive motor. The roll coater according to claim 2, wherein the linear movement means is formed by being axially attached to the roll coater.