JPH03151082A - Bar coating method - Google Patents

Abstract

PURPOSE:To prevent the sticking of a coating liquid on the rear of a substrate by stopping the rotating speed of a bar for a specific period of time during the time from just before the contact of the terminal part of the substrate with the bar to the completion of the complete contact. CONSTITUTION:The rotating speed of the bar 2 is lowered to <=1/5 the transporting speed of the substrate or the rotation of the bar is stopped when the position just before about 3 to 20mm from the terminal of the substrate 1 comes into contact with the bar 2. The substrate is in succession transported by receiving driving force from a pressing roll 15 under rotation at a specified speed. The coating speed is preferably set at about 0.1 to 20m/min. Paper, plastic film, resin coated paper, etc., having about 0.1 to 10mm thickness are used as the substrate. The contamination of the pressing roll is prevented in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of coating a discontinuous substrate using a bar.

Specifically, photoresist coating for sheet-shaped, disc-shaped, flat-shaped semiconductor wafers and photomasks used in their manufacture, solder resist cloth for printed circuit boards, glass substrate coating, etc., and especially used for LCD color TVs, etc. The present invention relates to a bar coating method suitable as a coating method for a novel color filter material.

[Conventional technology]

Japanese Patent Publication No. 58-4589 discloses that when uniformly coating a flexible continuous film (web) in a thin layer, a liquid pool is formed just before the contact portion of a rotating bar with the web. A method is disclosed in which a liquid is supplied and the bar continuously applies the coating liquid to the web. In this method, it is important that the web and bar are in complete contact with each other in the bar coater, and by wrapping the web at an appropriate angle (usually 15° to 60°) with respect to the bar, the adhesion between the two can be ensured. I keep it.

On the other hand, with a discontinuous substrate, the substrate itself is difficult to deform, and even if it deforms, it is discontinuous (sheet-like), so
It is not possible to wrap the bar under tension in the longitudinal direction. In order to apply the bar coater of Japanese Patent Publication No. 58-4589 to coating a discontinuous substrate, the inventors applied the coating while holding the substrate horizontally and pressing the substrate against the bar with a pressing member from above. Although it can be applied, it has been found that the following serious problems occur. In other words, if this method is applied to a discontinuous substrate (film) of several tens of centimeters to two meters in length, 1) the film thickness at the end of the substrate becomes X thicker than in the steady region, causing problems such as undeveloped parts, and 2) There are cases where the coating liquid adheres to the back side of the substrate at the end of the substrate, causing problems such as contaminating the pressing member and other processes.

[Problem to be solved by the invention]

Accordingly, an object of the present invention is to provide a bar coating method that solves the coating problem at the terminal end of a substrate when applying a coating liquid to a discontinuous substrate.

[Means to solve the problem]

After analyzing the reason for the occurrence of the above problem, it was found that part of the liquid in the liquid pool that forms just before the contact area between the bar and the board is transferred to the board at the end of the board. .

The above problem was solved by reducing the rotational speed of the bar to 115% of the substrate speed or stopping it from just before the end of the substrate contacts the bar until the contact is completely completed (Aspect 1). In the regular coating section, the speed of the bar is normally driven to be approximately equal to the speed of the substrate in order to prevent vibration of the substrate or the bar or scratches on the surface of the substrate due to slip between the substrate and the bar.

In addition, the above problem can be solved by moving the pressure roll upward from just before the end of the substrate leaves the bar until it completely leaves the bar, thereby widening the gap between the application bar and the pressure roll to prevent the pressure roll from coming into contact with the substrate. This was achieved by (Aspect 2).

According to the first aspect of the present invention, the amount of a liquid pool formed immediately before the contact portion between the bar and the substrate can be reduced by reducing or stopping the rotation of the bar.

The position where the rotational speed of the bar is reduced (or stopped) is 3 to 20 m + n from the end of the board, more preferably 5 m + n from the end of the board.
~10mm closer is better. If the stop position is too early, parts with uneven coating film thickness will penetrate inside the substrate, which is uneconomical.On the other hand, if the stop position is too late, sufficient thick coating prevention effect will not be obtained. .

According to the second aspect, the pressure roll separates from the substrate at the end of the substrate, and the substrate is no longer pressed against the coating bar by the pressure roll, but the close contact between the substrate and the coating bar is maintained due to the weight of the substrate, and coating is performed. The position to which the pressure roll is moved should be as close to the end of the substrate as possible, preferably as close to the end of the substrate as possible so that the coating surface is not disturbed by disturbances (pressing due to movement of the pressure roll causes sudden changes in pressure) in the regular application area. The distance from the end of the substrate is preferably within 10 mm, more preferably within 5 mm.

Particularly in the case where the thickness of the substrate is thin, for example, when the thickness is 1.5 or less, it is possible to effectively prevent the coating liquid from flowing to the end portion of the substrate.

Next, embodiments of the present invention will be described using the drawings.

FIG. 1 is a schematic view showing the bar coating method of the present invention, and FIG. 2 is a partially enlarged cross-sectional view of the bar coating apparatus of FIG. 1.

The bar 2 has a bar support member 6 over its entire length or a part thereof.
The bar 2 is horizontally and rotatably supported by the bar 2, and a rotation drive means (not shown) is connected to one end of the bar 2.

The bar support member 6 is surrounded by weir members 5 and 5';
The coating liquid 3 supplied from a liquid supply port 4 provided in a part of the core layer member 5 forms a liquid storage part 8 between the bar support member 6 and the weir member 5.

The substrate 1 to be coated is conveyed horizontally by a pass roll 14 and a pressure roll 15 in the direction of rotation of the bar 2 so that the lower surface of the substrate 1 is in contact with the top of the bar 2.

In FIG. 2, a rotating bar 2 draws up a coating liquid 3 from a liquid reservoir 8 and transfers the coating liquid 3 to the bottom surface of a substrate 1 through a liquid pool 9 formed at a point of contact with the bottom surface of a substrate 1. , shows how a coating film 7 of a predetermined thickness is formed by simultaneously performing measured scraping (by the action of the bar 2).

In the present invention, in order to uniformly apply the coating, it is important to bring the substrate 1 and the bar 2 into close contact over the entire width.

FIG. 1 shows a system in which a substrate 1 is conveyed by a pass roll 14 and a pressure roll 15. In this method, it is preferable to use an edge roll as the pass roll 14 so as to avoid contact with the lower surface of the substrate 1 as much as possible, and in this case, the bar may be a stepped bar 16 as shown in FIG. For example, by using a bar with the wire grooves in the ears crushed with solder, etc., and scraping off the liquid on the surface with the blade 21, creating uncoated areas on both sides of the board, it is possible to remove the coating after coating. The film can prevent the pass roll 14 from becoming dirty. Further, it is preferable to use a presser roll 15 having an elastic body such as rubber on its surface in order to bring the substrate 1 and the working bar 16 into close contact over the entire width. In addition, in Fig. 5, 21 is the blade, 22 is the coating surface,
23 represents a wire portion, and 24 represents a wire groove crushing portion.

In the present invention, an important element for uniform application is to maintain the liquid reservoir 9 in an optimal shape.

During substrate coating, the substrate 1 is intermittently fed, so the liquid pool 9 is intermittently formed. Therefore, it is necessary to devise a method so that the liquid pool 9 is formed in a steady state as soon as the substrate 1 comes into contact with the bar 2.

In the bar coating device 10 shown in FIG. 4, when the rotation of the bar 2 is stopped, the height Ll of the liquid level created by the coating liquid supplied to the side where the liquid pool 9 is to be formed and the height of the top of the bar 2. By setting the distance a to L2 in the range of 0.5 to 4.5 m, more preferably in the range of 1.0 to 4.0 m, the liquid pool 9 is quickly formed into a steady shape. .

If the distance a in FIG. 4 is larger than 4.5 mm, it will take time for the liquid pool 9 in FIG. 2 to reach a steady state, and the film thickness at the top of the substrate l will become unstable. Even after reaching a steady state, the shape of the liquid pool 9 tends to become uneven in the width direction, and vertical unevenness tends to occur. On the other hand, if the distance a is less than 0.5 mm, the liquid pool 9 becomes large and tends to cause uneven coating.

The height of the weir member 5 is adjusted appropriately so that the distance a falls within a predetermined range (target liquid level height). At this time, by setting the height of the weir member 5 to the same level as the target liquid level height, the target liquid level height can be easily maintained while allowing the coating liquid to overflow to some extent. However, if it is desired to prevent overflow for reasons such as saving the amount of coating liquid, the height of the weir member 5 can be set to be higher than the target liquid level height. However, in this case, it is preferable to control the amount of liquid fed without detecting the liquid level by rotating the bar. Generally, when a coating liquid is caused to overflow, the overflow does not occur uniformly across the entire width, but often occurs locally, unless the amount of liquid fed is excessive. At this time, depending on the coating liquid, the thickness of the coating may become uneven in the form of streaks in a portion of the overflow. Therefore,
In such a case, as shown in Fig. 2, the heights of the weir members 5 before and after the bar may be changed to allow overflow from the lower weir member, or a part of the weir member (outside of the coating width) may be overflowed. (preferably) can be made slightly lower to limit overflow to that location.

On the other hand, the distance c between the weir member 5 and the bar 2 shown in FIG.
e can also be windowed as appropriate.

Even if c and e are large, there is no problem in terms of coating, but it is not preferable because the coater becomes larger and the amount of liquid stored in the coater increases. On the other hand, if C is too narrow, the coating liquid from the liquid pool 9 tends to partially flow over the weir member, making it difficult to form a liquid pool in a stable state. Also, if e is too narrow, the downstream liquid level will drop due to the rotation of the bar,
This is not preferable because air tends to get trapped.

Therefore, it is preferable to set C and e to 3 to 20 mm.

In embodiment 1 of the present invention, when a position 3 to 20 mm before the end of the substrate 1 contacts the bar 2 in FIG. stop. The substrate is conveyed under the driving force of the press roll 15, which continues to rotate at a constant speed. Furthermore, in the second embodiment, the pressure roll 15 is moved upward in FIG. 1 to widen the gap between the coating bar 2 and the pressure roll 15, thereby solving the problem of the coating liquid adhering to the back side of the substrate at the end of the substrate. .

The material of the bar 2 used in the present invention is preferably metal (particularly stainless steel) in many cases in terms of strength and chemical resistance, but is not limited thereto, and may be a wire bar wrapped with plastic fiber such as nylon, Grooved bars made of rubber or plastic are also used.

As the wire bar, a roughing bar in which the outer peripheral surface of a wound wire is polished flat to increase the contact area with the substrate 1 can also be used.

The diameter of the bar 2 should preferably be in the range of 6.0 to 30.0 mm, more preferably 6.0 to 20.0 mm. It becomes difficult to produce.

When the bar 2 is a wire bar, the wire diameter is selected depending on the required coating film thickness, but if the cross section of the wire is circular and the substrate speed and the bar rotational peripheral speed are the same speed,
The wet coating film thickness is determined by the following relational expression, regardless of the substrate speed or the physical properties of the coating liquid.

That is, tζ70d However, t... Wet coating film thickness (μm), d... Wire diameter (mm) However, in order to obtain a good coating surface condition, the wire diameter range is preferably 0.05 -1.0 mm, more preferably 0.05-0.7 mm.

When bar 2 is a bar with IN=t, the groove pitch is usually l
mm or less, more preferably 0.7 mm or less.

It is suitable that the cross-sectional shape of the groove is close to a sinusoidal curve, but it is not necessarily limited to this and other shapes may also be used.

In the case of the above-mentioned rough pin bar or grooved bar, the wet coating thickness is determined by the volume per unit length of the space below the line connecting the vertices of the convex parts in each cross section. It has been found that the wet coating film thickness can be given in the approximate direction, and in either case, a bar with an appropriate shape can be selected within the above-mentioned preferred range.

By selecting the bar shape based on these findings, stable coating can be achieved from a thin coating with a wet coating amount of 4 cc/m' to a thick coating of approximately 70 cc/m''.

The coating speed in the present invention is in the range of 0.1 to 20 m/min, more preferably 0.2 m/min from the viewpoint of coating surface condition and operability.
A range of ~lQm/min is preferable.

In general, it is preferable to set the rotation peripheral speed of the bar 2 at the same speed as the coating speed to avoid slipping with the substrate 1. A better coated surface condition can often be obtained by lowering the rotational circumferential speed of the bar 2 within a range in which the rotation speed of the bar 2 is kept stable.

The substrate to be coated in the present invention is not particularly limited, and examples thereof include paper, plastic film, resin coated paper, metal plate, glass plate, etc., and the thickness is also not limited, but a substrate of about 0.1 to 10 mm is preferred. Preferably used.

The size of the substrate 1 in the present invention is not particularly limited. In general, in the case of glass substrates, the surface flatness tends to deteriorate as the size increases, but by using a pressure roll 15 with an elastic body on the surface shown in FIG. ) has been shown to be able to be coated sufficiently evenly on a square glass plate. Note that the substrate 1 can be well coated with either a rectangular or circular shape, and the shape is not particularly limited.

The method of the present invention allows a variety of liquids to be applied to discontinuous substrates. Although the composition and physical properties of the coating liquid are not particularly limited, those having a viscosity of 100 cp or less, particularly 50 cp or less are suitably applied.

Color filters can be suitably manufactured by the method of the present invention. Normally, when handling color images in an imaging device or display device, the wavelength of visible light is divided and extracted, photoelectrically converted, and the electrical energy is converted into light through the steps of amplification, transport, and amplification, and the corresponding colored light is generated. A method of displaying colored light by assembling it is being used. In general, each pixel, which is the smallest unit expressing image density, is colored B (blue).
The wavelengths are divided into three wavelengths: G (green) and R (red), and non-self-emitting imaging devices and display devices such as LCD TVs require additional filters, which are called color filters. There is.

Pigment-colored photosensitive compositions used in the production of color filters are disclosed in U.S. Pat. No. 3,549.3.
A photopolymerizable photosensitive composition comprising an addition-polymerizable unsaturated monomer, a photopolymerization initiator, and a binder disclosed in No. 67, etc., and a polymer having an unsaturated double bond residue in the main chain or side chain. Photocrosslinkable photopolymers are useful.

The addition polymerizable unsaturated monomer in the photopolymerizable photosensitive composition is a compound having at least one addition polymerizable ethylenically unsaturated group and a boiling point of 100° C. or higher at normal pressure.

For example, monofunctional acrylates and methacrylates such as polyethylene glycol mono (meth)acrylate, polypropylene glycol mono (meth)acrylate, phenoxyethyl (meth)acrylate; polyprolene glycol di(meth)acrylate, trimethylolethane tri(meth)acrylate, etc. ) acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, hexanediol(
meth)acrylate, melimethylolpropane tri(
Acryloyloxyfurovir) ether, tri(acryloyloxyethyl)in cyanurate, polyfunctional alcohols such as glycerin and trimethylolethane added with ethylene oxide or propylene oxide and then converted into (meth)acrylates. -41708
No., Special Publication No. 50-6034, Japanese Patent Publication No. 51-37193
Urethane acrylates as described in each publication, JP-A-48-64183, JP-A-49-4319
Polyfunctional acrylates and methacrylates such as polyester acrylates and epoxy acrylates which are reaction products of epoxy resin and (meth)acrylic acid described in Japanese Patent Publication No. 1 and Japanese Patent Publication No. 52-30490 can be mentioned. I can do it. Furthermore, Japan Adhesive Association Journal Vol. 20
, N (L7. Those introduced as photocurable monomers and oligomers on pages 300 to 308 can also be used. The amount used is 5 to 50 wt% (hereinafter abbreviated as %), preferably 10 to 40%. .

As a photopolymerization initiator, U.S. Patent No. 2.367, 660
Vicinal polyketaldonyl compounds disclosed in US Pat. Nos. 2,367,661 and 2
．． 367.670, the acyloin ethers disclosed in U.S. Pat. No. 2.448.828, U.S. Pat.
722,512, the α-hydrocarbon substituted aromatic acyloin compounds disclosed in U.S. Patent No. 3.
046,127 and 2.951,758, U.S. Patent No. 3.5
49,367, a combination of triallylimidazole dimer/p-aminophenyl ketone, and a benzothiazole compound/trihalomethyl-S-) liazine compound disclosed in Japanese Patent Publication No. 48516/1983. , the photosensitive S-) described in Japanese Patent Application No. 61-186238! J azine compounds, trihalomethyl-5-triazine compounds disclosed in U.S. Pat. No. 4,239,850, U.S. Pat. No. 4,21
Examples include oxadiazole compounds described in No. 2.976.

The amount used is about 0.2 to 20% in terms of solid content, preferably 0.2 to 20%.
It is 5-15%.

The binder is preferably a linear organic polymer that is compatible with the monomer, is soluble in an organic solvent, and can be developed with a weak alkaline aqueous solution. Examples of such linear organic polymers include polymers having carboxylic acid in the side chain, such as JP-A-59-44615 and JP-B-Sho 54-3.
No. 4327, Special Publication No. 12577, Special Publication No. 1977-
No. 25957, JP-A No. 59-53836, JP-A No. 59-Sho.
-71048, methacrylic acid copolymers, acrylic acid copolymers, itaconic acid copolymers, crotonic acid copolymers, maleic acid copolymers, partially esterified maleic acid copolymers. Similarly, there are acidic cellulose derivatives having a carboxylic acid in the side chain.

In addition, polymers having hydroxyl groups to which acid anhydrides are added are also useful. Among these, benzyl (meth)acrylate/(meth)acrylic acid copolymer and benzyl (meth)acrylate/(meth)acrylic acid/
and multi-component copolymers with other monomers are preferred. Other useful water-soluble polymers include polyvinyl pyrrolidone, polyethylene oxide, and polyvinyl alcohol. Alcohol-soluble nylon and polyether of 2,2-bis-(4-hydroxyphenyl)-furopane and epichlorohydrin are also useful in order to increase the strength of the cured film. These polymers can be mixed in any amount, but if it exceeds 90%, it will not give favorable results in terms of the strength of the image formed. Preferably it is 30-85%.

In addition to the above, it is preferable to further add a thermal polymerization inhibitor, such as hydroquinone, p-methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, etc. '-thiobis(3-methyl-6-t-butylphenol), 2
．． 2'-methylenebis(4-methyl-6-t-butylphenol), 2-mercaptobenzimidazole, and the like are useful.

A suitable amount of thermal polymerization inhibitor is usually added to commercially available monomers.

As a photocrosslinkable photopolymer, for example, JP-A-52
- the polyester compound disclosed in No. 96696,
British Patent No. 1,112,277, British Patent No. 1.313.3
No. 90, No. 1.341.004, No. 1.377.
They include polyvinyl cinnamate-based photosensitive polymers described in specifications such as No. 747 and JP-A No. 55-23941.

Useful organic solvents for the photosensitive composition include glycol ether-based methyl cellosolve, ethyl cellosolve, propyl cellosolve, propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol propyl ether and their acetates, i.e., methyl cellosolve acetate; Ethyl cellosolve acetate, flobyl cellosolve acetate, flopylene gellicol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol probyl ether acetate are useful. Acetate esters include amyl acetate, butyl acetate, propyl acetate, and ethyl acetate, and ketones include methyl isobutyl ketone, methyl ethyl ketone,
Acetone, cyclohexanone, dimethylformamide, dimethylsulfoxide, methylpyrrolidone, γ-butyrolactone, ethyl lactate, and the like are useful, and each alkyl group may be a linear or branched isomer.

The solution concentration can range from 3% to 70%, with a more preferred range being 15% to 50%.

The coloring materials include, for example, azo, anthraquinone, xanthine, quinacridone, indigo, dioxazine, indanthrone, isoindolinone, phthalocyanine, triphenylmethane, nitroso, perylene, Isoindoline pigments are useful, e.g.
Phthalocyanine Blue (C, 1, Pigment Blue 15
:6 or C,1, Pigment Blue 15:3: For example, Lionor Blue ES manufactured by Toyo Ink Manufacturing ■, Chromo Blue A3R manufactured by Ciba Gaiki Co., Ltd.), Phthalocyanine Green (C,1, Pigment Green 7.36, or C , 1, Pigment Green 37: For example, Toyo Ink Manufactured Side Glue Onol Green 2YS), Perylene pigment (C11, Pigment Red 155, Anthraquinone pigment (C, I, Pigment Red 177: For example,
Lionogen Red GD (manufactured by Toyo Ink Seisakusho), Chromophthal Red BRN (manufactured by Ciba Geigy), etc. are useful, and C, 1, Pigment Yellow 83, etc. are also useful for color correction.
,C',1. Pigment Yellow 154: For example, Lionogen Yellow 30 manufactured by Toyo Ink Manufacturing ■. C11, Pigment Violet 23: For example, Toyo Ink Manufacturing ■
Particularly preferred are Lionogen Violet RL manufactured by Co., Ltd.

The coloring material is dispersed in the photocurable photosensitive composition to produce a colored photosensitive composition.

The proportion of the pigment in the photosensitive layer is 5 to 90 in terms of solid content.
%, more preferably 10 to 60%.

〔Effect of the invention〕

According to the present invention, it is possible to effectively prevent the coating liquid from going around to the back side of the terminal end of the discontinuous substrate.

In particular, according to the method according to claim 1, it is possible to prevent an increase in film thickness at the end portion of a discontinuous substrate.

Therefore, according to the coating method of the present invention, coated substrates can be efficiently produced, and since coating can be performed in a horizontal state, it is suitable for coating materials that are highly rigid and difficult to bend, such as glass substrates.

Therefore, when wiping photoresist coating for semiconductor wafers or photomasks used in their manufacture, solder resist coating for printed circuit boards, glass substrate coating, etc.
The present invention provides an economically superior coating method that enables uniform coating even on large-sized substrates or substrates of arbitrary shapes, and reduces loss of coating liquid.

Further, when the method of the present invention is applied to a method for manufacturing a color filter, a solution of a colored photosensitive composition can be evenly applied over a large area.

Therefore, by the method of the present invention, liquid crystal color displays, liquid crystal color televisions, color image pickup tubes, color image sensors, etc. can be manufactured easily and at low cost.

Next, the present invention will be explained with reference to examples.

〔Example〕

Example 1 Using the bar coating device 10 shown in FIGS. 1 and 2, 7 Otoresist solution was applied onto a glass substrate measuring 45 cm x 45 cm and 1.1 mm thick. As the bar 2, a stainless steel wire having a diameter of 0.15 mm was wound around a stainless steel wire having a diameter of 12 mm.

In Fig. 4, when the rotation of the bar 2 is stopped, the liquid pool 9
The height L of the liquid level created by the coating liquid supplied to the side where the
The distance a between + and the height L2 of the top of bar 2 was maintained at 2 carp. Further, the distances between C and e were each set to 8 mm.

The conveyance speed of the substrate was 3 m/min, and the rotational speed of the wire bar in the steady application section was 3 m/min, which was the same speed as the substrate.

(i) When the rotational speed of the bar is not changed at the end of the substrate, a thick coating of 5 to 10 mm in width and 3 to 10 times as thick as the steady portion occurs at the end of the substrate a, and occasionally due to the reverse rotation, the film thickness roll 15 Dirt occurred on the surface.

(ii) If the rotation of the bar is stopped 5 mm before the end of the board, the thick coating width at the end of the board must be within 3 mm.
The amount of thick coating was within twice that of the steady area. Further, no back-turning occurred at the end of the substrate.

Example 2 Using the bar coating device 10 shown in FIGS. 1 and 2, a photoresist solution was applied onto a glass substrate measuring 45 cm x 45 cm and 0.7 mm thick. In FIG. 4, the distance a between the height L+ of the liquid level created by the coating liquid supplied to the side where the liquid pool 9 is to be formed when the rotation of the bar 2 is stopped and the height L2 of the top of the bar 2 is It was maintained at 2+11111. Also, the distance between C and e was set to 8m each.

The pressure roll 15 is an aluminum roll with a diameter of 10 cm and a rubber lining with a thickness of 2 mm on the surface.
carried a 12a+m diameter stainless steel wire wrapped with 0.15 mm diameter stainless steel wire.

The gap between the pressing roll and the bar was 0.5 mm.

Further, the conveyance speed of the substrate (defined by the rotation speed of the pressure roll and the rotation speed of the edge roll 140) and the rotation speed of the coating bar were both 3 m/min.

(i) When the position of the pressure roll was not changed at the end of the substrate, in all samples, back-turning occurred at the end of the substrate, and staining occurred on the pressure roll 15.

(ii) Starting from 5m before the end of the board, move the pressure roll to 0.0m.
5 When the crucian carp was moved upward to prevent contact between the pressure roll and the substrate, no turning occurred at all in all samples.
Therefore, no staining of the press roll occurred.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of the bar coating method of the present invention, and Fig. 2 is a schematic diagram of the bar coating method of the present invention.
A partially enlarged cross-sectional schematic diagram of the coating device used in the coating method shown in the figure.
Fig. 3 is a perspective view of the stepped bar, Fig. 4 is an explanatory diagram showing the position of the liquid pool surface when the bar rotation is stopped in the bar coating device shown in Fig. 1, and Fig. 5 uses a bar with grooves on both ends. FIG. 1... Board, 2... Bar 3...
Coating liquid, 4...Liquid supply hole, 5...Weir member, 6...Bar support member, 7...Coating film, 8...Liquid storage part, 9...・Liquid pool, 10... Bar coating device, 14...
Bath roll, 15...press roll, 16...
・Stepped Bar Diagram Diagram Diagram Diagram Diagram Diagram Diagram Diagram Diagram Diagram Diagram Diagram Diagram Diagram Diagram II

Claims (2)

[Claims] (1) A discontinuous substrate is moved while being held between a coating bar and a pressing member, and a liquid pool is formed immediately before the contact portion of the bar that rotates in the same direction as the substrate while contacting the substrate. In a bar coating method in which a coating liquid is supplied so that the coating liquid is applied to the substrate by the bar, the bar is applied from just before the terminal end of the substrate contacts the bar until the contact is completely completed. A bar coating method characterized in that the rotation speed of the bar is 1/5 or less of the substrate speed or the rotation of the bar is stopped. (2) A discontinuous substrate is moved horizontally while being held between a coating bar and a pressure roll, and a liquid pool is formed immediately before the contact portion of the bar that rotates in the same direction while contacting the substrate with the substrate. In a bar coating method in which a coating liquid is supplied to the substrate and the coating liquid is applied to the substrate by the bar, a pressure roll is moved upward from just before the terminal end of the substrate leaves the bar until it completely leaves the bar. A bar coating method characterized by widening the gap between the coating bar and the pressure roll to prevent the pressure roll and the substrate from coming into contact with each other.