JPH05337431A - Method for applying coating liquid to substrate surface by roll coater - Google Patents

Abstract

PURPOSE:To keep the consumption of a coating liquid all over the process to a necessary minimum by controlling the supplied quantity of the coating liquid so as to be smaller in a period when an applicator roll does not come into contact with the surface of a substrate than in a period when the applicator roll comes into contact with the surface of the substrate. CONSTITUTION:In a method for applying a coating liquid to the surface of a substrate by a roll coater, the coating liquid is supplied to the peripheral surface of an applicator roll 12 having elasticity at least in the surface layer part and the peripheral cylindrical surface of the applicator roll 12 is rotated while it is brought into contact with and pressed to the surface of each substrate 1 horizontally carried in order at intervals on a horizontal stage 46 for transferring a substrate arranged under the applicator roll 12 and the coating liquid is applied to the surface of plural substrate 1 in order. And in a period when the peripheral cylindrical surface of the applicator roll 12 does not come into contact with the surface of the substrate 1, compared to a period when it does so, the supplied quantity of the coating liquid from the applicator roll 12 to the substrate 1 in the direction of the stage 46 for transferring a substrate is controlled so that it may be smaller.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a roll coater to transfer a glass substrate for liquid crystal, a substrate for an image sensor, a substrate such as a semiconductor substrate, and the like in sequence horizontally while keeping an interval between them. By contacting or pressing and rotating the surface of each substrate, a coating liquid, for example, a photoresist liquid, a polyimide resin, or the like is sequentially applied to the substrate surface through an applicator roll, and the surface of a plurality of substrates is uniformly and predeterminedly coated. The present invention relates to a method for forming a coating film having a film thickness of.

[0002]

2. Description of the Related Art As a roll coater of this type,
For example, a structure as shown in FIG. 5 is used.
In this roll coater, the outer peripheral cylindrical surface of the doctor roll 3 is brought close to the outer peripheral cylindrical surface of the applicator roll 2 in which at least the surface layer portion of the outer peripheral cylindrical surface is made of an elastic material such as a rubber material. 3, a liquid reservoir 4 is formed above the liquid reservoir 4, and a coating liquid supply pipe 5 for supplying a coating liquid such as a photoresist liquid into the liquid reservoir 4 is provided above the liquid reservoir 4. A plurality of transport rolls 6 for horizontally transporting the substrate 1 such as a glass substrate for liquid crystal are arranged below the applicator roll 2, and a backup is provided so as to face the applicator roll by sandwiching the horizontal transport path. It is configured by disposing the roll 7.
Then, in order to form a coating film having a predetermined film thickness such as a photoresist film on the surface of the substrate using this roll coater, the coating liquid is supplied from the coating liquid supply pipe 5 to the liquid reservoir 4 and the applicator roll is used. 2 and the backup roll 7 are rotated, the substrate 1 is horizontally transported by the transport roll 6, and the substrate 1 is placed between the applicator roll 2 and the backup roll 7.
The coating liquid is transferred from the outer peripheral cylindrical surface of the applicator roll 2 to the surface of the substrate 1 by passing through.

Further, as another configuration example of the roll coater,
For example, Japanese Utility Model Application Laid-Open No. 2-133470 discloses a stage for adsorbing and holding a substrate and conveying it in a horizontal direction, a liquid reservoir for storing a coating liquid, and one or several coating liquids supplied from the liquid reservoir. A configuration in which a coating liquid supplied through a roll or the like is held in a thin film on the outer peripheral cylindrical surface, and an applicator roll having at least the surface layer portion of the outer peripheral cylindrical surface made of an elastic material such as rubber is provided. The roll coater is disclosed. To use this roll coater to form a coating film of a specified thickness on the surface of the substrate, rotate the applicator roll on the surface of the substrate that is adsorbed and held on the stage and transferred in the horizontal direction. The surfaces are brought into contact or pressed so that the coating liquid is transferred from the outer peripheral cylindrical surface of the applicator roll to the surface of the substrate. Therefore, when the outer peripheral cylindrical surface of the applicator roll is in contact with the substrate surface, or when the outer peripheral cylindrical surface of the applicator roll is pressed against the substrate surface, a part of the outer peripheral cylindrical surface of the applicator roll is elastically deformed. In, the coating liquid is applied.

By the way, in each of the roll coaters as described above, when the axial length of the outer peripheral cylindrical surface of the applicator roll is longer than the width dimension of the substrate, the outer peripheral cylindrical surface of the applicator roll moves to the surface of the substrate. When the coating liquid is transferred and the coating liquid is applied to the substrate surface, the width of the substrate of the outer peripheral cylindrical surface of the applicator roll at the position rearward of the contact position with the substrate surface in the rotation direction of the applicator roll. The coating liquid remains on both sides exceeding the size without being transferred to the substrate surface. Then, the remaining coating liquid is brought into the liquid reservoir from the outer peripheral cylindrical surface of the applicator roll, and from the outer peripheral cylindrical surface of the applicator roll, the outer periphery of the coating liquid supply roll that rotates reversely with respect to the applicator roll. The quality of the fresh coating liquid brought into the liquid reservoir through the cylindrical surface and stored in the liquid reservoir is deteriorated. Further, when the substrates are sequentially conveyed in the horizontal direction at intervals and are fed to the position below the applicator roll, the outer peripheral cylindrical surface of the applicator roll is not in contact with the substrate surface (during the interval). Has
The coating liquid adhering to the outer peripheral cylindrical surface of the applicator roll is returned to the liquid reservoir without being transferred to the surface of the substrate, and the quality of the fresh coating liquid in the liquid reservoir is deteriorated. As a result, it becomes impossible to meet the demand for higher precision of the coating film.

In order to solve the above-mentioned problem due to the returning of the coating liquid from the outer peripheral cylindrical surface of the applicator roll to the inside of the liquid reservoir, as shown in FIG. A scraper 8 for collecting the residual coating liquid is attached to the rear side of the contact position between the outer peripheral cylindrical surface and the surface of the substrate 1 so as to face the outer peripheral cylindrical surface of the applicator roll 2. The residual coating liquid is scraped off from the outer peripheral cylindrical surface of and is collected in the tray 9.

[0006]

However, conventionally, a constant amount of a substrate is always fed from the applicator roll to the horizontal transport path of the substrate regardless of whether or not the substrate is fed to a position below the applicator roll. The coating liquid is supplied. For this reason, when there is no substrate at the coating position directly below the applicator roll, that is, when the outer peripheral cylindrical surface of the applicator roll is not in contact with the substrate surface (during the interval), the outer peripheral cylindrical surface of the applicator roll adheres. The applied coating liquid remains on the outer peripheral cylindrical surface of the applicator roll without being transferred to the substrate surface, and the remaining coating liquid is
There is a problem that the scraper is scraped off from the outer peripheral cylindrical surface of the applicator roll and is wasted without being used, resulting in a large consumption of the coating liquid as a whole process.

The present invention has been made in order to solve the above-mentioned problems and eliminates wasteful consumption of coating liquid.
It is an object of the present invention to provide a coating liquid application method capable of suppressing the consumption amount of the coating liquid as a whole process to a necessary minimum.

[0008]

A coating solution is supplied to an outer peripheral cylindrical surface of an applicator roll having at least a surface layer portion having elasticity, and a horizontal conveying path disposed below the applicator roll is spaced from the coating liquid. In a method of sequentially applying a coating liquid to the surfaces of a plurality of substrates by rotating the outer peripheral cylindrical surface of the applicator roll while contacting or pressing the surface of each substrate sequentially conveyed in the horizontal direction, the present invention provides an application method. When the outer cylindrical surface of the troll is not in contact with the surface of the substrate, the direction of the horizontal transfer path from the applicator roll to the substrate is more than when the outer cylindrical surface of the applicator roll is in contact with the surface of the substrate. Control was performed so that the amount of coating liquid supplied to the device was reduced.

In order to reduce the supply amount of the coating liquid from the applicator roll in the direction of the horizontal transfer path of the substrate at the time when the outer peripheral cylindrical surface of the applicator roll is not in contact with the surface of the substrate, the outer periphery of the applicator roll is reduced. The gap between the cylindrical surface and the outer peripheral cylindrical surface of the coating liquid supply roll arranged close to the outer peripheral cylindrical surface may be narrowed. Further, at least when the outer peripheral cylindrical surface of the applicator roll is not in contact with the surface of the substrate, the rotation speed of the applicator roll may be slowed.

As another configuration, the outer peripheral cylindrical surface of the applicator roll is arranged so that the outer peripheral cylindrical surface is in contact with or close to the outer peripheral cylindrical surface of the plurality of substrates sequentially conveyed in the horizontal direction at intervals. When the coating liquid is transferred from the installed coating liquid supply roll to the outer peripheral cylindrical surface of the applicator roll and the coating liquid is sequentially applied, the coating liquid is not applied on the substrate surface but remains on the outer peripheral cylindrical surface of the applicator roll and remains coated. The coating liquid transferred to the liquid supply roll again faces the outer peripheral cylindrical surface of the coating liquid supply roll at a position rearward from the contact position with the outer peripheral cylindrical surface of the applicator roll in the rotation direction of the coating liquid supply roll. By a scraper arranged in such a manner as to be removed from the outer peripheral cylindrical surface of the coating liquid supply roll, in the time when the outer peripheral cylindrical surface of the applicator roll is not in contact with the surface of the substrate , The scraper is controlled so as not to remove the coating liquid from the outer peripheral cylindrical surface of the coating liquid supply roll, and the coating liquid remaining on the outer peripheral cylindrical surface of the applicator roll is applied to the surface of the next substrate. It was adapted to be used for liquid application.

[0011]

[Function] When the outer peripheral cylindrical surface of the applicator roll is not in contact with the surface of the substrate, compared to the time when the outer peripheral cylindrical surface of the applicator roll is in contact with the surface of the substrate,
Since the amount of coating liquid supplied from the applicator roll to the horizontal transfer path of the substrate is controlled to be small, the applicator roll outer cylindrical surface is not transferred from the applicator roll outer cylindrical surface to the substrate surface. The amount of the coating liquid remaining on the surface is reduced, and the wasteful consumption of the coating liquid is eliminated.

Further, at a time when the outer peripheral cylindrical surface of the applicator roll is not in contact with the surface of the substrate, the operation of removing the coating liquid from the outer peripheral cylindrical surface of the coating liquid supply roll is not performed by the scraper, and the applicator roll The coating liquid remaining on the outer peripheral cylindrical surface of the is used to apply the coating liquid to the surface of the next substrate, so the coating liquid supplied to the outer peripheral cylindrical surface of the applicator roll is effectively used, and the coating liquid is wasted. Consumption is lost.

[0013]

The preferred embodiments of the present invention will be described below.

FIG. 1 is a perspective view of an essential part showing one structural example of a roll coater used for carrying out a method for applying a coating liquid on a surface of a substrate according to the present invention. 2 and 3 are schematic diagrams for explaining an operation of applying a coating liquid, for example, a photoresist liquid on the surface of a substrate, for example, a glass substrate for liquid crystal, by a roll coater.

The roll coater 10 shown in FIG. 1 includes an applicator roll 12 and an upper part of the applicator roll 12.
The pair of coating liquid supply rolls 14, 16 are arranged in parallel with each other in the same horizontal plane, and the outer peripheral cylindrical surfaces are close to each other, and one outer peripheral cylindrical surface is in contact with or close to the outer peripheral cylindrical surface of the applicator roll 12. And have. Then, the coating liquid is supplied from a coating liquid supply source (not shown) to the liquid reservoir 48 formed in the upper part of the contact portions of the coating liquid supply rolls 14 and 16, and the coating liquid is stored in the liquid reservoir 48. Coating liquid supply roll
Applicator roll from the liquid reservoir 48 with the rotation of 14
The coating liquid is supplied to the outer peripheral cylindrical surface of 12.
The three rolls 12, 14, 16 are provided on the left and right support plates 18, 20.
A drive motor 22 for rotationally driving the applicator roll 12 is mounted on one of the support plates 20. Further, both support plates 18 and 20 include a drive motor 24, a worm gear 26 fixed to the rotation shaft of the drive motor 24, left and right worm wheels 28 and 30 meshed with the worm gear 26, and respective worm wheels. It has a male screw portion that is screwed into a female screw formed in the central portion, is slidably inserted into through holes formed in the left and right fixing members 36, 38, and its upper end portion is supported by each of the support plates 18, 20. An up-and-down drive mechanism composed of left and right vertical rods 32 and 34 that abut on and support the shafts can be simultaneously swung in the up-and-down direction with the support shafts 49 and 49 as fulcrums. Further, the support plates 18 and 20 are provided with the left and right biasing devices 4 fixed to the fixing members 36 and 38, respectively.
It is always urged downward by 0 and 42. A rail 44 is disposed horizontally in a position directly below the applicator roll 12 and in a direction orthogonal to the applicator roll 12, and is guided by the rail 44 and driven horizontally by a drive mechanism (not shown). A substrate transfer stage 46 is provided which is reciprocally movable in any direction. The stage 46 has a built-in suction holding mechanism, and the stage 46 has a large number of suction holes (not shown) formed on the upper surface thereof.
The substrate 1 is sucked and held on the substrate 46.

The roll coater shown in FIG. 2 is composed of an applicator roll 12, a knife roll 50 as a doctor having a notch step on the outer peripheral cylindrical surface, and a knife roll 50 close to the applicator roll. A metal roll 52 that rotates in the same direction as the applicator roll 12 in contact with or close to 12 is provided, and the knife roll 50 is configured to be able to approach and separate from the metal roll 52 within a certain range. A liquid reservoir 54 for the coating liquid is formed on the upper portion of the vicinity of the metal roll 52. Further, a scraper 56 is attached to the metal roll 52. The applicator roll 12 is pivotally attached to the support frame 62, and the support frame 62 is pivotally attached to a base (not shown) via a support shaft 64. By swinging the support frame 62 with respect to the base in a vertical plane about the support shaft 64, the entire roll unit including the applicator roll 12, the metal roll 52, and the knife roll 50 is moved, and the applicator roll is moved. The roll 12 can be moved in the vertical direction. In FIG. 2, the drive mechanism of the roll unit, the drive mechanism of the substrate transfer stage 46, the urging devices 40 and 42, etc. are omitted from the drawing.

The roll coater shown in FIG. 3 includes an applicator roll 12, a liquid reservoir 66 for coating liquid, a gravure roll 68 as a rotatable doctor disposed near the liquid reservoir 66, and the gravure roll. Roll 68 and applicator roll
Offset rubber roll 7 that rotates in contact with 12
In addition, the scraper roll 72 attached to the offset rubber roll 70 is provided, and the gravure roll 68 is configured to be movable by a fixed amount of pushing with respect to the offset rubber roll 70. The support frame 78 is pivotally attached to a base (not shown) via a support shaft 80, and by swinging the support frame 78 about the support shaft 80, the applicator roll 12, the gravure roll 68, and the offset rubber roll 70. And scraper roll
The applicator roll 12 can be moved in the vertical direction by moving the entire roll unit consisting of 72.

Using the roll coater having the above-mentioned structure, the coating liquid is applied on the surface of the substrate by the following method.

The substrate 1 is sucked and held on the stage 46 by the suction holding mechanism of the substrate transfer stage 46, the stage 46 is moved in the horizontal direction, and the substrate 1 is applied as shown by solid lines in FIGS. 2 and 3. Transfer to the position directly below the troll 12. At this time, in the applicator roll 12, the lowermost part of the outer peripheral cylindrical surface is slightly higher than the surface of the substrate 1,
For example, wait at a position about 1 mm higher, and
In the direction indicated by the arrow in Fig. 2 (Figs. 2 and 3 show
A case of performing reverse coating is illustrated), and a thin film of a coating liquid having a predetermined thickness is adhered and held on the outer peripheral cylindrical surface thereof. Then, while transferring the substrate 1, the applicator roll 12 is moved downward from the standby position, so that the front end of the substrate 1 moves to a point on the vertical line passing through the rotation axis of the applicator roll 12, that is, the lowermost part of the applicator roll 12. When passing, the applicator roll 12 is brought into contact with the surface of the substrate 1. After the applicator roll 12 comes into contact with the surface of the substrate 1, the applicator roll 12 is subsequently moved downward and the applicator roll 12 is pushed against the surface of the substrate 1. Then, when the applicator roll 12 is pushed in by a predetermined pushing amount, the downward movement of the applicator roll 12 is stopped, and the applicator roll 12 is placed on the substrate 1.
While being pressed against the surface of the substrate 1, the applicator roll 12 is rotated while moving the substrate 1 in the horizontal direction, so that the coating liquid is applied to the surface of the substrate 1 with a uniform thickness.
When the application of the coating liquid on the surface of the substrate 1 is completed, the applicator roll 12 is moved upward and pulled up to the standby position.

The above-described series of coating liquid coating operations are repeatedly performed on a plurality of substrates 1 which are successively conveyed in the horizontal direction at intervals, as shown by the solid lines in FIGS. 2 and 3. Compared to the time when the outer peripheral cylindrical surface of the applicator roll 12 is in contact with the surface of the substrate 1 and the coating liquid is applied to the surface of the substrate 1, the outer peripheral cylindrical surface of the applicator roll 12 is the substrate as indicated by the two-dot chain line. 1 is not in contact with the surface of the substrate 1 from the applicator roll 12 to the substrate 1
It is controlled so that the supply amount of the coating liquid in the direction of the horizontal conveyance path is reduced. For this purpose, in the roll coater shown in FIG. 2, the knife roll 50 is movable with respect to the metal roll 52, and the interval between the outer peripheral cylindrical surface of the knife roll 50 and the outer peripheral cylindrical surface of the metal roll 52 is adjusted to For example, the interval is set to 20 μm during application of the coating liquid, and the interval is set to 5 μm during the interval. Further, in the roll coater shown in FIG. 3, by increasing the pushing amount of the gravure roll 68 with respect to the offset rubber roll 70, the applicator roll 12
The amount of the coating liquid remaining on the outer peripheral cylindrical surface of the applicator roll 12 without being transferred from the outer peripheral cylindrical surface of the substrate 1 to the surface of the substrate 1 is reduced, and wasteful consumption of the coating liquid is eliminated.

In the above description, the supply amount of the coating liquid from the applicator roll to the horizontal transfer path of the substrate is controlled to be small during the interval in which the coating liquid is not applied to the substrate surface. In addition, the gap between the knife roll and the metal roll is narrowed, or the pushing amount of the gravure roll with respect to the offset rubber roll is increased, but in the roll coater shown in FIG. 5, the doctor roll functioning as a coating liquid supply roll is used. 3 may be configured to be able to approach and separate from the applicator roll 2 by a predetermined distance, and the interval between the two may be narrowed during the interval. Further, by controlling the respective rotation speeds of the metal roll, the gravure roll and the applicator roll during the interval so as to slow down at least the rotation speed of the applicator roll, the applicator roll is directed in the direction of the horizontal transport path of the substrate. The supply amount of the coating liquid may be reduced.

As shown in FIG. 4, the metal roll 52
A scraper 82 is provided at a position on the rear side of the contact position with the outer peripheral cylindrical surface of the applicator roll 12 in the rotation direction of, so as to face the outer peripheral cylindrical surface of the metal roll 52, and the scraper 82 applies the scraper 82 to the surface of the substrate 1. It is a roll coater that scrapes off the coating liquid that remains on the outer peripheral cylindrical surface of the applicator roll 12 and is transferred to the metal roll 52 again and collects it in the tray 84. Of the applicator roll 12 during the interval in which the outer peripheral cylindrical surface of the applicator roll 12 is not in contact with the surface of the substrate 1, the scraper 82 is separated from the outer peripheral cylindrical surface of the metal roll 52. The operation of removing the coating liquid from the outer peripheral cylindrical surface of the roll 52 is prevented, and the coating liquid remaining on the outer peripheral cylindrical surface of the applicator roll 12 is transferred to the surface of the next substrate. It can be adapted to be used for coating liquid application. This allows the applicator roll 12
The coating liquid supplied to the outer peripheral cylindrical surface of is effectively used, and wasteful consumption of the coating liquid can be eliminated.

[0023]

Since the present invention is constructed and operates as described above, when the coating liquid is applied to the substrate surface by using the roll coater according to the method of the present invention, the consumption of the coating liquid is wasted. It is possible to eliminate the consumption of the coating liquid in the entire process to a necessary minimum.

[Brief description of drawings]

FIG. 1 is a perspective view of a principal part showing a configuration example of a roll coater used for carrying out a method for applying a coating liquid on a substrate surface according to the present invention.

FIG. 2 is a schematic diagram for explaining an operation of applying a coating liquid on the surface of a substrate with a roll coater.

FIG. 3 is a schematic diagram for explaining an operation of applying a coating liquid on the surface of a substrate by a roll coater having another configuration.

FIG. 4 is a schematic diagram for explaining an operation of applying a coating liquid on the surface of a substrate by a method according to another configuration.

FIG. 5 is a schematic diagram for explaining an operation of applying a coating liquid on the surface of a substrate by a conventional method.

[Explanation of symbols]

 1 Substrate 10 Roll coater 12 Applicator roll 46 Stage 52 Metal roll (Coating liquid supply roll) 70 Offset rubber roll (Coating liquid supply roll) 82 Scraper

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area H01L 21/027

Claims (5)

[Claims] 1. A coating liquid is supplied to an outer peripheral cylindrical surface of an applicator roll having at least a surface layer portion having elasticity, and is horizontally sequentially arranged at intervals on a horizontal conveying path arranged below the applicator roll. In the method of sequentially applying the coating liquid to the surfaces of a plurality of substrates by rotating the outer peripheral cylindrical surface of the applicator roll while contacting or pressing the outer peripheral cylindrical surface of each substrate to be transferred, the outer peripheral cylindrical surface of the applicator roll Is not in contact with the surface of the substrate, compared to the time when the outer peripheral cylindrical surface of the applicator roll is in contact with the surface of the substrate, the coating liquid in the direction of the horizontal transfer path from the applicator roll to the substrate. A method for applying a coating liquid onto a substrate surface by a roll coater, which is characterized by controlling the supply amount to be small. 2. The coating liquid is supplied to the outer peripheral cylindrical surface of the applicator roll through a coating liquid supply roll in which the outer peripheral cylindrical surface is arranged in proximity to the outer peripheral cylindrical surface of the applicator roll. The control is performed so that the distance between the outer peripheral cylindrical surface of the applicator roll and the outer peripheral cylindrical surface of the coating liquid supply roll is narrowed when the outer peripheral cylindrical surface of the applicator roll is not in contact with the surface of the substrate. The method for applying a coating liquid onto a substrate surface by the roll coater described above. 3. The roll coater according to claim 1, wherein the rotation speed of the applicator roll is controlled to be slowed at least when the outer peripheral cylindrical surface of the applicator roll is not in contact with the surface of the substrate. Coating method. 4. The coating liquid supply roll is arranged such that the outer peripheral cylindrical surface of the applicator roll is in contact with or close to the outer peripheral cylindrical surface, and the coating liquid supplied from the coating liquid supply roll to the applicator roll. A doctor that controls the amount of liquid is placed in contact with or close to the outer peripheral cylindrical surface of the coating liquid supply roll, and when the outer peripheral cylindrical surface of the applicator roll is not in contact with the surface of the substrate, the applicator roll Compared to the time when the outer peripheral cylindrical surface of the is in contact with the surface of the substrate, the interval between the outer peripheral cylindrical surface of the coating liquid supply roll and the doctor is narrowed,
Alternatively, the method of applying the coating liquid onto the substrate surface by the roll coater according to claim 1, wherein the amount of pushing of the doctor with respect to the outer peripheral surface of the coating liquid supply roll is controlled to be large. 5. A coating liquid supply roll, which is arranged such that at least a surface layer portion of the applicator roll is elastic so that the outer peripheral cylindrical surface of the applicator roll is in contact with or in proximity to the outer peripheral cylindrical surface of the applicator roll. The coating liquid is supplied, and the outer peripheral cylindrical surface of the applicator roll is brought into contact with or pressed against the surface of each substrate that is sequentially transported in the horizontal direction on the horizontal transport path arranged below the applicator roll. While being rotated, the coating liquid was sequentially applied to the surfaces of a plurality of substrates, and the coating liquid was not applied to the substrate surfaces but remained on the outer peripheral cylindrical surface of the applicator roll and transferred to the coating liquid supply roll again. The coating liquid is disposed at a position rearward of the contact position with the outer peripheral cylindrical surface of the applicator roll in the rotation direction of the coating liquid supply roll so as to face the outer peripheral cylindrical surface of the coating liquid supply roll. A method of removing the coating liquid supply roll from the outer peripheral cylindrical surface by a scraper, wherein the scraper is used when the outer peripheral cylindrical surface of the applicator roll is not in contact with the surface of the substrate. The above operation of removing the coating liquid from the outer peripheral cylindrical surface of the coating liquid supply roll is controlled so as not to be performed, and the coating liquid remaining on the outer peripheral cylindrical surface of the applicator roll is applied to the surface of the next substrate. A method for applying a coating liquid onto a substrate surface by a roll coater, which is used for.