JP2003126753A - Bar coating apparatus and bar coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a bar coating apparatus and a bar coating method by which uniform coating surface quality is obtained particularly even when a coating objective material having a rough surface in surface roughness is transported at high speed. SOLUTION: The transporting time until an aluminum web 14 is brought into contact with a measuring bar 16B after being in contact with a previous adhering bar 16A is controlled to <=0.25 sec. As a result because the reproduction or the growth of entrained air between the previous adhering bar 16A and the measuring bar 16B is prevented even in the aluminum web 14 having the rough surface in surface roughness, the uniform coating surface quality is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bar coating device and a bar coating method, and more particularly to a bar coating device and a bar coating device capable of coating a coating liquid at a high speed onto a coating object conveyed in a fixed direction. The present invention relates to a bar coating device and a bar coating method which are preferably applicable particularly when the surface roughness of an object to be coated is rough.

[0002]

2. Description of the Related Art Conventionally, for example, as shown in FIG. 5, in order to apply a coating liquid to an object to be coated such as a metal plate or to remove an excess coating liquid from the object to be coated (so-called weighing). Bar applicator 102 may be used.

In the bar coating device 102, the metal plate 10 is conveyed with respect to the metal plate 104 conveyed at a constant conveying speed.
The cylindrical coating bar 106 is arranged so as to be in contact with the coating surface (lower surface) of the metal plate 104 in a direction orthogonal to the transportation direction of 4 (direction of arrow F1). Coating bar 1
06 rotates due to friction with the metal plate 104 at a peripheral speed equal to the transport speed of the metal plate 104. By this rotation, the coating liquid 108 is scraped up, and the dam member 112 and the metal plate 104 are
A liquid pool 110 is formed between the above and. That is, the coating liquid in the liquid pool 110 is applied to the metal plate 104, and the excess coating liquid is removed (measured) from the metal plate 104.

However, in such a bar coating device 102, so-called entrained air is caught during coating,
The liquid pool 110 may not be stable. Particularly in recent years, the transport speed of the metal plate 104 may be increased, but this increase in speed increases the possibility that the liquid pool 110 will not be stably maintained. When the liquid pool 110 becomes unstable, it is difficult to obtain a uniform coating surface quality, for example, the coating liquid 108 is not evenly spread over the entire width direction of the metal plate 104. Further, particularly when the surface roughness of the metal plate 104 is rough, entrained air is likely to be generated, so that it is more difficult to obtain a uniform coating surface quality.

[0005]

SUMMARY OF THE INVENTION In consideration of the above facts, the present invention provides a bar capable of obtaining a uniform coating surface quality, in particular, even for a coating object having a rough surface roughness, even if the conveying speed is increased. An object is to obtain a coating device and a bar coating method.

[0006]

According to a first aspect of the present invention, there is provided a pre-wearing bar for contacting a coating object conveyed in a certain direction to pre-deposit the coating solution on the coating object, and the pre-preparation bar. It is arranged on the downstream side of the wear bar in the conveying direction of the application target,
A measuring bar for measuring the coating liquid with respect to the application object, and a time interval from the contact of the application object with the pre-wear bar to the contact with the measurement bar is 0.25 seconds. It is characterized in that the interval between the pre-wear bar and the weighing bar is set so as to be within the range.

That is, in this bar coating device, first, the coating liquid is pre-deposited on the conveyed coating object by the pre-deposition bar to form a pre-deposition coating layer. Thereby, the entrained air of the coating object can be removed. Next, the coating liquid is measured by a measuring bar to form a desired coating layer on the object to be coated. In this way, by using the two coating bars (pre-wearing bar and measuring bar) for coating the coating liquid on the coating object, entrained air can be reduced (preferably so that it does not occur). ), Uniform coating surface quality can be obtained over the entire width direction of the coating object.

Particularly, in this bar coating device, the pre-wear bar and the metering bar are set so that the time interval from the contact of the application object to the pre-wear bar to the contact of the metering bar is within 0.25 seconds. The distance from the bar is set. This allows
Since it is possible to prevent reoccurrence or growth of entrained air between the application target object and the weighing bar, for example, when the surface roughness of the application target is rough (as an example, the arithmetic mean roughness Ra is Even if it is 0.20 μm or more), a uniform coating surface quality can be obtained.

According to a second aspect of the present invention, in the first aspect of the present invention, at least one of the pre-wear bar and the weighing bar has a peripheral speed different from the peripheral speed corresponding to the conveying speed of the object to be coated. And a rotary drive device for rotating at high speed.

That is, at least one of the pre-wear bar and the weighing bar is not rotated by friction with the object to be coated, but is rotated so as to have a peripheral speed different from the peripheral speed corresponding to the conveying speed of the object to be coated. It is actively rotated by the drive device. As a result, the liquid pool can be stabilized, so that uniform coating surface quality can be obtained even when, for example, the transport speed of the coating object is increased or the viscosity of the coating liquid is increased.

According to the third aspect of the present invention, a pre-adhering step of pre-adhering the coating liquid to the coating object by bringing the pre-wearing bar into contact with the coating object conveyed in a certain direction, and the pre-depositing step. And a measuring step of measuring the coating liquid by bringing the measuring bar into contact with the coating object, and the transfer time of the coating object between the pre-wearing bar and the measuring bar is 0. ．
It is characterized in that it is set within 25 seconds.

That is, in this bar coating method, first, the coating liquid is pre-deposited in the pre-deposition step on the conveyed coating object to form a pre-deposition coating layer. Thereby, the entrained air on the application target can be removed. Next, in the measuring step, the coating liquid is measured to form a desired coating layer on the object to be coated. In this way, by performing the two coating steps (pre-adhesion step and metering step) for applying the coating liquid to the object to be coated, the entrained air is reduced (preferably not generated), and the object to be coated is reduced. A uniform coated surface quality can be obtained over the entire width direction of the object.

Particularly, in this bar coating method, the transfer time of the object to be coated between the pre-wear bar and the weighing bar is 0.25.
It is set within seconds. This can prevent reoccurrence or growth of entrained air between the pre-loading bar and the weighing bar, so that, for example, when the surface roughness of the coating target is rough (for example, arithmetic mean roughness Ra is 0.
Even if it is 20 μm or more), a uniform coating surface quality can be obtained.

According to a fourth aspect of the invention, in the third aspect of the invention, at least one of the pre-wear bar and the weighing bar has a peripheral speed different from the peripheral speed corresponding to the conveying speed of the object to be coated. It is characterized by rotating at high speed.

That is, at least one of the pre-wear bar and the weighing bar is not rotated by friction with the object to be coated, but is rotated so as to have a peripheral speed different from the peripheral speed corresponding to the conveying speed of the object to be coated. It is actively rotated by the drive device. As a result, the liquid pool can be stabilized, so that uniform coating surface quality can be obtained even when, for example, the transport speed of the coating object is increased or the viscosity of the coating liquid is increased.

In a fifth aspect of the present invention, the invention according to the third or fourth aspect is characterized in that a coating liquid containing an organic solvent is used as the coating liquid.

That is, when a coating solution containing an organic solvent is used, entrained air is particularly likely to be generated because the coating solution applied by the pre-wear bar evaporates quickly. Since the coating liquid is applied to the object to be coated by the bar coating method according to claim 3 or 4, the generation of entrained air can be prevented more reliably.

According to a sixth aspect of the present invention, in the invention according to any of the third to fifth aspects, the ambient temperature of the portion from the pre-wear bar to the weighing bar is maintained at 30 ° C. or lower. It is characterized by

As a result, it is possible to prevent excessive evaporation of the coating liquid in the portion from the pre-wear bar to the measuring bar, and to more reliably prevent the generation of entrained air.

[0020]

1 shows a bar coating apparatus 12 according to an embodiment of the present invention. This bar coating device 1
No. 2 is incorporated in the planographic printing plate production line, and the coating solution 50 is applied to the aluminum web 14 which is the base material of the planographic printing plate.
It is used to apply (photosensitive liquid, etc.). The aluminum web 14 is transported at a predetermined transport speed in the longitudinal direction by a transport device (not shown). Hereinafter, when simply referred to as “conveyance direction”, it means the conveyance direction of the aluminum web 14, which is indicated by arrow F in the drawings. Also, simply "width direction"
In this case, it means the width direction of the aluminum web 14 and is indicated by an arrow W in the drawing.

The bar coating device 12 includes coating units 13 having substantially the same structure, and these coating units 13 are arranged at a predetermined interval in the carrying direction. As will be described later, the coating unit 13A on the upstream side in the transport direction pre-deposits the coating liquid 50 on the aluminum web 14. On the other hand, the coating unit 13 on the downstream side in the transport direction
B measures the coating liquid 50 on the aluminum web 14.

Each coating unit 13 has a coating bar 16 arranged so as to come into contact with the aluminum web 14 from below, and the coating bar 1 on the upstream side in the conveying direction.
6 is a pre-loading bar 16A, and a coating bar 1 on the downstream side in the transport direction.
6 acts as a weighing bar 16B. The coating bar 16 is formed in a substantially columnar shape (or a substantially cylindrical shape),
It is supported by the bearing member 18 so that its longitudinal direction coincides with the width direction of the aluminum web 14.

The upper surface of the bearing member 18 is a supporting surface 18S formed in an arc shape along the outer peripheral surface of the coating bar 16, and the coating bar 16 is in contact with the supporting surface 18S. It is rotatably supported.

Barrier plates 20 and 22 are arranged on the upstream side and the downstream side of the bearing member 18, respectively. A predetermined gap is formed between each of the dam plates 20 and 22 and the bearing member 18, and in particular, the gap between the dam plate 20 and the bearing member 18 on the upstream side of each coating unit 13 supplies the coating liquid. It is designated as road 24. Upstream coating unit 13A
Then, the coating liquid 5 sent from the coating liquid supply device (not shown)
0 passes through the coating liquid supply path 24, and the coating liquid 50 is sequentially scraped up by the rotation of the coating bar 16 and transferred to the aluminum web 14. Further, on the upstream side of the contact portion between the aluminum web 14 and the coating bar 16, a liquid pool 52 of the coating liquid 50 is formed between the aluminum web 14, the dam plate 20 and the coating bar 16. Downstream coating unit 13
In B, the coating liquid 50 is similarly transferred to the aluminum web 14 and a part of the coating liquid 50 is removed from the aluminum web 14 (substantially one of the coating liquid 50 attached to the aluminum web 14 is removed). Parts are exchanged).

The two coating units 13 are integrally held by a holder 28, and a coater 30 is constructed as a whole. Support rolls 32 and 34, which are in contact with the aluminum web 14 from the opposite side (that is, the upper side) of the coater 30, are arranged on the upstream side and the downstream side of the coater 30. When the support rolls 32 and 34 press the aluminum web 14 from above, the aluminum web 14 can be brought into contact with the coating bar 16 while applying a predetermined tension to the aluminum web 14.

By driving an elevating device (not shown), the two coating units 13 (the bearing member 18 and the dam plates 20 and 22) constituting the coater 30 can be integrally elevated. As shown in FIG. 1 (A), in the lowered state, neither of the coating bars 16 contacts the aluminum web 14, so the coating liquid 50 is not coated, but they are raised as shown in FIG. 1 (B). As a result, the coating bar 16 is brought into contact with the aluminum web 14 and the coating liquid 50 can be coated. Further, while maintaining the contact state, the coater 30 is slightly moved up and down to obtain a desired contact pressure and a desired wrap angle, so that it is possible to perform coating according to the types of the aluminum web 14 and the coating liquid 50.

Here, in the bar coating device 12 of this embodiment, the time from the contact of the aluminum web 14 with the pre-wear bar 16A to the contact with the weighing bar 16B is taken into consideration in consideration of the conveying speed of the aluminum web 14. The coating bar 16A is adjusted so that the (conveyance time in the present invention) is within 0.25 seconds.
And the measuring bar 16B (that is, the distance between the upstream coating unit 13A and the downstream coating unit 13B) is set.

2 and 3 show a schematic structure of a rotary drive device 36 for rotationally driving the coating bar 16.

The rotary drive device 36 includes a motor, a speed reducer, etc., and has a drive source 38 for generating a rotary drive force at a predetermined torque and angular velocity. Drive source 38
A shaft 44 is connected to the output shaft 40 of the first via a first universal joint 42, and the shaft 44 is
Via the second universal joint 46, the switching member 48
Are linked to. The switching member 48 is disconnected from the transmission position (position shown by the solid line in FIG. 2) which is connected to the coating bar 16 and can transmit the rotational driving force, and does not transmit the rotational driving force by being disconnected from the coating bar 16. It moves between the non-transmission position (the position indicated by the chain double-dashed line in FIG. 2).

Since the drive source 38 and the coating bar 16 are connected via the two universal joints in this manner, the angle of the coating bar 16 with respect to the output shaft 40 of the drive source 38 is always constant. The rotational drive force of the drive source 38 can be transmitted to the coating bar 16 while maintaining constant (parallel in the present embodiment). For example, even when the coater 30 is slightly moved up and down, or when the coater 30 is lowered to separate the coating bar 16 from the aluminum web 14 as shown by the chain double-dashed line in FIG. Axis 40
And the coating bar 16 are parallel to each other, and the coating bar 16 is rotated by the rotational driving force of the driving source 38.

In the bar coating device 12 of this embodiment, the peripheral speed of the coating bar 16 is different from the peripheral speed corresponding to the transport speed of the aluminum web 14 (including both the same direction and the opposite direction). As described above, it is possible to positively rotate the coating bar 16 by the rotational driving force from the driving source 38.

Next, a method of applying the coating liquid 50 to the aluminum web 14 by the bar coating device 12 of the present embodiment and the operation of the bar coating device 12 will be described.

When the coating liquid 50 is applied to the aluminum web 14, the aluminum web 1 is moved by a carrier device (not shown).
4 is conveyed at a constant conveying speed.

Further, the coater 30 is raised as shown in FIG. 1 (B), and the pre-wearing bar 16A and the weighing bar 16 are
Both of the Bs are in contact with the aluminum web 14,
The coating liquid 50 is supplied from a coating liquid supply device (not shown).

At this time, first the aluminum web 14 is
The coating liquid 50 scraped up by the pre-wearing bar 16A is transferred to form a pre-coating coating layer 54 on the aluminum web 14. This reduces (preferably eliminates) the generation of so-called entrained air in the aluminum web 14.
be able to.

Next, as the aluminum web 14 is conveyed,
The coating liquid constituting the pre-deposition coating layer 54 is measured by the measuring bar 16B. That is, the excess amount of the coating liquid of the aluminum web 14 is removed by measuring,
While the deficiency is compensated for, the entire film is made uniform and a desired amount of coating film is formed. In this way, two coating bars 16 (pre-wear bar 1
6A and the bar for measurement 16B) and the coating process (pre-deposition process and measurement process) are performed twice in succession to reduce entrained air (preferably not to occur), and an aluminum web. A uniform coating surface quality can be obtained over the entire width direction of 14.

Particularly, in the bar coating device 12 of this embodiment, the transport time from the contact of the aluminum web 14 with the pre-wear bar 16A to the contact with the weighing bar 16B is 0.2.
It is within 5 seconds. If the transport time is longer than 0.25 seconds, especially in the case of the aluminum web 14 having a rough surface, after being pre-deposited by the pre-deposition bar 16A, it is pre-deposited before reaching the weighing bar 16B. Although entrained air may be regenerated or grown in the layer 54, in the present embodiment, such entrained air can be prevented from being regenerated or grown, so that aluminum having a rough surface is used. Even with the web 14, uniform coating surface quality can be obtained.

Further, in the bar coating device 12 of the present embodiment, at the time of coating, as shown by the solid line in FIG.
Can be moved to the transmission position, and the rotational driving force of the drive source 38 can be transmitted to the coating bar 16. As a result, the coating bar 16 is positively rotated at a peripheral speed different from the peripheral speed corresponding to the transport speed of the aluminum web 14.

As shown in FIG. 4, generally, the liquid pool 52 formed between the aluminum web 14, the barrier plate 20 and the coating bar 16 is a contact portion between the aluminum web 14 and the coating bar 16. When viewed from T (shown by the one-dot chain line in FIG. 4), the coating surface quality becomes good when the edge portion 52E of the liquid pool 52 draws a periodic curve in the width direction. When 52E has a sinusoidal curve or a shape close to this, the coated surface quality is further improved.

In the present embodiment, as described above, the peripheral speed of the coating bar 16 is set to a peripheral speed different from the peripheral speed corresponding to the transport speed of the aluminum web 14, so that the edge of the liquid pool 52 is formed. The shape of the portion 52E is a shape close to a sine curve,
The liquid pool 52 is stably maintained. Therefore, coating streaks and the like (due to the disturbance of the liquid pool) do not occur in the applied coating liquid 50, and it is possible to obtain a uniform coating surface quality.

In particular, even when a high-viscosity coating liquid 50 is used or the transport speed of the aluminum web 14 is increased, the edge portion 52E of the liquid pool 52 has a shape close to a sine curve. Since the liquid pool 52 can be stably maintained, the quality of the coated surface can be made uniform. From this viewpoint, the rotation speed of the coating bar 16 is not particularly limited as long as it is a peripheral speed (including both normal rotation and reverse rotation) different from the peripheral speed corresponding to the transport speed of the aluminum web 14.

Of course, depending on the conveying speed of the aluminum web 14, the viscosity of the coating liquid 50, and other conditions, it may be better to rotate (follow) the coating bar 16 by friction with the aluminum web 14 as in the conventional case. . In that case, the rotation driving force of the drive source 38 is not easily transmitted to the coating bar 16 simply by moving the switching member 48 to the non-transmission position as shown by the chain double-dashed line in FIG. Is possible.

The coating bar 16 rotated at a peripheral speed different from the peripheral speed corresponding to the transport speed of the aluminum web 14 is
Either one or both of the pre-loading bar 16A and the weighing bar 16B may be used.
4 and the viscosity of the coating liquid 50 and other conditions.

As the coating bar 16 of the present invention, a bar having a flat peripheral surface, a wire bar in which wires are closely wound in the circumferential direction of the peripheral surface of the bar to form a groove between adjacent wires, and further, It is possible to use a grooved bar or the like in which a groove is formed in the circumferential direction of the bar circumferential surface over the entire width of the bar or in a necessary portion. The outer diameter of the coating bar 16 is preferably in the range of φ1 to 30 mm, and in the range of φ3 to 25 mm, from the viewpoints of bar rolling accuracy (straightness / roundness), rotational moment, weight balance, and the like. Is more preferable, and the range of φ6 to 15 mm is particularly preferable. As a material for the coating bar 16, a metal is preferable from the viewpoint of corrosion resistance and strength, and stainless steel is particularly suitable.

If a wire bar is used, a suitable wire diameter is 0.07 to 1.0 mm, preferably 0.07.
It is up to 0.6 mm, and metal is used as the material of the wire, but stainless steel is most suitable from the viewpoint of corrosion resistance, wear resistance, strength and the like. The wire bar may be plated on the surface to further improve wear resistance, and hard chrome plating is particularly suitable. When a wire bar is used, the coating amount in each coating unit 13A, 13B can be adjusted by the size (diameter) of the wire.

When a groove cutting bar is used in the present invention, the groove pitch is preferably 0.05 to 1.0 mm, preferably 0.1 to 0.6 mm, and the cross-sectional shape approximates to a sine curve. Those with a trapezoidal shape are suitable. However, the sectional shape is not necessarily limited to such a sectional shape, and another sectional shape can be used. In order to further improve the wear resistance of this groove cutting bar, the surface can be plated, and hard chrome plating is particularly suitable. When the groove cutting bar is used, the coating amount in each of the coating units 13A and 13B can be adjusted depending on the size (width and depth) of the groove.

Whichever construction of the coating bar 16 is adopted, the coating amount on the aluminum web 14 after passing through the coating unit 13B on the downstream side has a desired quality of the planographic printing plate as the final product. Therefore, the coating amount is necessary. Therefore, the coating amount of the coating bar 16 (measuring bar) of the coating unit 13B on the downstream side is usually 3 to 1
It is often set at 00 ml / m ² .

The wrap angle of the aluminum web 14 (object to be coated) with respect to each coating bar 16 is not particularly limited as long as the coating solution can be reliably applied (pre-adhered or measured) to the aluminum web 14. The range of 1 to 30 ° is preferable, and the range of 2 to 20 ° is more preferable. In addition,
The lap angle can be set to a desired value by adjusting the vertical position (the amount of rise) of the coater 30.

The bearing member 18 is not limited as long as it can reliably support the coating bar 16, but considering that the coating bar 16 may rotate at a high speed, the coating bar 16 (wire In the case of a bar, a bar having a low coefficient of friction with a wire is preferable for smooth rotation of the coating bar 16, and a bar having high abrasion resistance is preferable. Fluorine resins, polyacetal resins, polyethylene resins, etc. can be mentioned as those satisfying these conditions, and among these, Teflon (R)
Polytetrafluoroethylene known under the name of (trade name of DuPont, USA) and polyacetal resin known under the name of Delrin (trade name of DuPont, USA) are particularly preferable in terms of friction coefficient and strength (abrasion resistance). Is. Further, those obtained by adding a filler such as glass fiber, graphite or molybdenum disulfide to these plastic materials can also be used. Further, after the bearing member 18 is made of a metal material, the surface of the bearing member 18 may be coated or adhered with the above-mentioned plastic material to reduce the friction coefficient between the bearing member 18 and the coating bar 16. Alternatively, various metal materials impregnated with the above plastic material (for example, aluminum impregnated with polytetrafluoroethylene) can be used for the bearing member 18.

Further, the coating liquid 5 is applied by the bar coating device 12.
As an application object (support) for applying 0, a metal such as aluminum (the aluminum web 14 described above), paper, plastic film, resin-coated paper, synthetic paper, or the like can be used. When an aluminum plate is used as a support for a lithographic printing plate, for example, JIS 1050 material, JI
S1100 material, JIS1070 material, Al-Mg alloy,
Al-Mn-based alloy, Al-Mn-Mg-based alloy, Al-Z
An r-based alloy, an Al-Mg-Si-based alloy, or the like can be applied. In this case, mechanical surface roughening treatment, chemical etching treatment, electrolytic surface roughening treatment, anodic oxidation treatment, etc. are generally carried out individually or in combination. In the case of plastic film, polyethylene, polypropylene and other polyolefins, polyvinyl acetate, polyvinyl chloride,
Vinyl polymers such as polystyrene, 6,6-nylon, 6
-Polyamide such as nylon, polyethylene terephthalate, polyester such as polyethylene-2,6-naphthalate, polycarbonate, sertostoacetate,
Cellulose acetate such as cellulose diacetate is used. In addition, as a resin (resin) used for the resin-coated paper, a polyolefin such as polyethylene is typical, but the resin is not limited thereto.

The thickness of the aluminum web 14 is not particularly limited, but one having a thickness of about 0.01 mm to 1.0 mm is advantageous in handling and versatility.

The surface roughness of these objects to be coated is not particularly limited, but when the surface roughness is rough, the liquid pool 5
In many cases, 0 becomes unstable and it is difficult to obtain a uniform coated surface quality. Therefore, for example, when the arithmetic mean roughness Ra of the coating object is 0.20 μm or more, if the coating liquid 50 is coated using the bar coating device 12 of the present embodiment, a more uniform coating surface quality is obtained. be able to.

Further, the coating liquid 50 is not limited to the above-mentioned photosensitive liquid, and for example, an aqueous solution of a polymer compound or an organic solvent solution, a pigment dispersion liquid, a colloidal solution or the like can be used. Examples of the coating liquid 50 for forming the photosensitive layer of the planographic printing plate include photosensitive liquids that form the photosensitive layers of the following aspects (1) to (11). (1) A mode in which the photosensitive layer contains an infrared absorber, a compound that generates an acid by heat, and a compound that crosslinks by an acid. (2) A mode in which the photosensitive layer contains an infrared absorber and a compound that becomes alkali-soluble by heat. (3) A mode in which the photosensitive layer includes two layers, a layer containing a compound that generates radicals by laser irradiation, an alkali-soluble binder, and a polyfunctional monomer or prepolymer, and an oxygen barrier layer. (4) A mode in which the photosensitive layer comprises two layers of a physical development nucleus layer and a silver halide emulsion layer. (5) A mode in which the photosensitive layer includes three layers of a polymerized layer containing a polyfunctional monomer and a polyfunctional binder, a layer containing silver halide and a reducing agent, and an oxygen barrier layer. (6) A mode in which the photosensitive layer includes two layers, a layer containing a novolac resin and naphthoquinonediazide, and a layer containing silver halide. (7) A mode in which the photosensitive layer contains an organic photoconductor. (8) A mode in which the photosensitive layer includes two or three layers including a laser light absorption layer that is removed by laser light irradiation and a lipophilic layer and / or a hydrophilic layer. (9) A compound in which the photosensitive layer absorbs energy to generate an acid, a polymer compound having a functional group in the side chain to generate a sulfonic acid or a carboxylic acid by the acid, and an acid generator by absorbing visible light Embodiments containing a compound that gives energy to (10) A mode in which the photosensitive layer contains a quinonediazide compound and a novolac resin. (11) A mode in which the photosensitive layer contains a compound that decomposes by light or ultraviolet rays to form a cross-linked structure with itself or other molecules in the layer, and an alkali-soluble binder.

Further, among the coating liquids, those containing an organic solvent tend to generate entrained air. However, by coating the aluminum web 12 with the coating liquid by the bar coating device 12 of this embodiment, the entrained air is generated. Can be prevented more reliably.

The viscosity of the coating liquid 50 is not particularly limited, either.
100 mPa · s or less is preferable, and 50 mPa · s or less is more preferable.

The temperature around the bar coating device 12 (particularly the temperature from the pre-wear bar 16A to the measuring bar 16B) is not particularly limited, but if the temperature in this region exceeds 30 ° C. There is a high possibility that entrained air will be regenerated or grown in the coating layer 54. Therefore, it is preferable that the temperature of at least the portion from the pre-wearing bar 16A to the measuring bar 16B be 30 ° C. or lower.

As the bar coating device 12 of the present invention, the bar coating device 12 for coating the aluminum web 14 (support) with the photosensitive liquid was taken up in the above description for the production line for producing the planographic printing plate. Not limited.

[0058]

EXAMPLES The present invention will now be described in more detail by way of examples, but the present invention is not limited to these examples.

Example In this example, the bar coating device 12 of the present invention was used to apply the coating liquid 50 to the aluminum web 14.
Was applied.

First, the surface of a strip-shaped aluminum plate is subjected to mechanical surface roughening treatment, chemical etching treatment, electrolytic surface roughening treatment and anodic oxidation treatment so that the arithmetic average roughness Ra is 0.20.
A substrate having a thickness of μm (aluminum web 14) and a substrate having a thickness of 0.26 μm (aluminum web 14) were obtained. The coating liquid 50 is applied to these aluminum webs 14 by the bar coating device 12,
The coated surface quality was evaluated and the coated state was observed.

The coating conditions were set as follows.

・ Width of aluminum web: 500 mm ・ Thickness of aluminum web: 0.3 mm ・ Conveying speed: 150 m / min ・ Coating amount preloading bar: 0.05 liter / m ² weighing bar: 0.015 liter / m ²・ Diameter of coating bar: 10 mm (both two) ・ Rotation speed of coating bar Preloading bar: Same speed in aluminum web direction (driven rotation) Weighing bar: -50 / min (reverse rotation)・ Viscosity of coating liquid: 20 mPa · s Usually, the aluminum web 1 in the planographic printing plate manufacturing process
The transportation speed of No. 4 is often 50 m / min or less. Therefore, the above conveying speed (150 m / min) is
The transport speed of the aluminum web 14 in the planographic printing plate manufacturing process is relatively high.

Under the above-mentioned coating conditions, the intervals between the upstream coating unit 13A and the downstream coating unit 13B are set variously, and after the aluminum web 14 comes into contact with the pre-wear bar 16A, the measuring bar 16B is contacted. The time until contact (conveying time in the present invention) was changed, and the coating liquid was applied to the aluminum web 14 to obtain a lithographic printing plate.

Table 1 shows the evaluation and observation results. Note that no significant difference was found in the results between the aluminum webs 14 having an arithmetic average roughness of 0.20 μm and 0.26 μm. Therefore, in Table 1, the arithmetic average roughness is 0.26 μm.
The case where the aluminum web 14 is applied will be shown.

[0065]

[Table 1] In the evaluation in the table, "○" indicates that the result is good, and no problems or inconveniences occur. "△" is slightly inferior to "○", but it depends on the type and use of the planographic printing plate. In practical use, there is no problem or inconvenience. In this respect, it is sufficiently practical, and “x” indicates that a problem or inconvenience may occur.

As can be seen from this table, the transfer time is 0.
In the case of 20 seconds or less (Example 1 and Example 2), the coating surface quality is good. When the transport time is 0.25 seconds (Example 3), the coated surface quality is lower than in Examples 1 and 2, but there is no problem depending on the type and application of the lithographic printing plate. It has become a degree.

On the other hand, when the transport time is 0.28 seconds (comparative example), the coating film is not formed and uniform coating surface quality is not obtained.

[0068]

Since the present invention has the above-mentioned constitution, in particular,
It is possible to obtain a uniform coating surface quality even if the conveyance speed is increased with respect to the coating object having a rough surface.

[Brief description of drawings]

FIG. 1 is a front view showing a schematic configuration of a bar coating apparatus according to an embodiment of the present invention, (A) is a non-coated state, and (B) is a coated state.

FIG. 2 is a plan view showing a rotation driving device of the bar coating device according to the first embodiment of the present invention.

FIG. 3 is a side view showing a rotation driving device of the bar coating device according to the first embodiment of the present invention.

FIG. 4 is a perspective view illustrating a coating state by a coating bar in the bar coating device according to the first embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a schematic configuration of a conventional bar coating device.

[Explanation of symbols]

12-bar coating device 14 Aluminum web (application target) 16 Coating bar 16A pre-wear bar 16B weighing bar 20 Weir plate (weir member) 36 rotary drive 50 coating liquid 52 Liquid pool

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2H025 AA18 AB03 DA20 EA04                 4D075 AC22 AC34 AC72 AC84 AC94                       CA47 DA04 DB07 DC19 DC27                 4F042 AA22 BA04 BA05 CC09 DF15

Claims (6)

[Claims] 1. A pre-wearing bar that comes into contact with an object to be coated that is conveyed in a fixed direction to pre-deposit the coating liquid to the object to be coated, and a downstream side of the pre-wearing bar in the transport direction of the object to be coated. A measuring bar arranged to measure the coating liquid with respect to the coating object, and a time interval from the contact of the coating object to the pre-wear bar to the contact with the measuring bar is 0. The bar coating device is characterized in that the interval between the pre-wear bar and the weighing bar is set so as to be within 25 seconds. 2. A rotary drive device for rotating at least one of the pre-wear bar and the weighing bar so as to have a peripheral speed different from the peripheral speed corresponding to the conveying speed of the coating object. The bar coating device according to claim 1. 3. A pre-adhesion step of pre-adhering a coating liquid to an application target object by bringing a pre-attachment bar into contact with the application target object conveyed in a fixed direction; And a measuring step of measuring the coating liquid by bringing the measuring bar into contact with the measuring bar, and the transfer time of the coating object between the pre-wearing bar and the measuring bar is set within 0.25 seconds. The bar coating method is characterized in that 4. The preloading bar and at least one of the weighing bars are rotated so as to have a peripheral speed different from the peripheral speed corresponding to the transport speed of the coating object. Bar coating method described. 5. The bar coating method according to claim 3, wherein a coating liquid containing an organic solvent is used as the coating liquid. 6. The bar coating method according to claim 3, wherein an ambient temperature of a portion from the pre-wear bar to the weighing bar is maintained at 30 ° C. or lower. .