JP3385494B2 - Coating device and photosensitive material manufactured using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for applying a coating liquid on a conveyed support while allowing the coating liquid to flow down while being propagated between a pair of edge guides.

[0002]

2. Description of the Related Art As an apparatus for applying a coating to a continuous support being conveyed, many methods such as bead coating using a slide coater, extrusion coating, and curtain coating have been proposed.

Curtain coating means, as shown in the perspective view of FIG. 9, a uniform coating liquid is supplied from the slits 5 provided on the slide surface 4 to form a thin film of the coating liquid. In this method, the thin film coating liquid is dropped while being transmitted between the pair of edge guides 6 while keeping the thin film state, and is made to collide with the conveyed continuous support to perform coating. When coating is performed using this method, there is a drawback in that the thickness of the coated portion becomes uneven in the width direction of the continuous support.

The cause of this is that the thin film coating liquid shrinks in the gap D between the tip portion 7 of the edge guide 6 that supports the thin film coating liquid and the support 2 to be conveyed. Figure
FIG. 10 is a view of the portion where the thin film coating liquid is applied to the support, as viewed from the transport direction of the support. As soon as the thin film of the coating liquid is separated from the edge guide 6, both edges of the thin film due to surface tension. The part contracts toward the central part of the thin film. When coating is performed in this state, the film thickness at the widthwise both edges of the coating liquid applied on the support is larger than that at the center, so that a so-called side thick film is produced, Causes unevenness of film thickness in the coated area. FIG. 11 is a cross-sectional view in the width direction of the coated continuous support, that is, a front cross-sectional view showing a coated portion where a side thick film is formed.

As a method for eliminating such unevenness of the film thickness, for example, in Japanese Patent Publication No. 3-500858, the method of devising the shape of the edge guide, and in Japanese Examined Patent Publication No. 56-73579, both the coated support and the coated support are used. A method of removing the side thick film portion of the edge portion with an aspirator is described.

Generally, when performing curtain coating in the process of reversing the conveying direction of the support conveyed by the backup roller 1 or the like, as shown in a partial side view of FIG. On the other hand, the coating liquid formed in the shape of a curtain film is supplied, and then the liquid receiving means 10 is retracted as shown in the partial side view of FIG. The term "retraction" is used in this specification to mean that the liquid receiving means 10 moves to a position where it does not interfere with the application.

In the above-described conventional structure, the relationship between the edge guide 6, the continuous support 2 to be conveyed, and the liquid receiving means is that the coating liquid separated from the edge guide 6 collides with the support 2. The liquid receiving means 10 is arranged in the tangential direction of the support in the coating liquid contact portion, which is the position to be set, the thin film coating liquid is started to be supplied, the coating means 3 is moved to the coating position, and then the liquid receiving means is tangentially received. The means 10 was retracted so as to be pulled out, and coating on the support was started.

Here, in order to prevent the side thick film,
On the support carried by the backup roller 1,
A coating liquid contact portion where the coating liquid comes into contact with the support 2,
The gap D (referred to as “coating gap D” in this specification) at the tip portion 7 of the curtain edge guide 6 must be shortened.

Therefore, in order to shorten the coating gap D,
A method of reducing the plate thickness of the liquid receiving means is conceivable. However, in this case, the liquid receiving means 10 has a slack, and the liquid receiving means comes into contact with the central region of the continuous support to be conveyed in the conveying direction. Since it is unfavorable, a certain degree of rigidity is required so that the liquid receiving means will not be distorted, and it is impossible to make it thinner than a certain thickness by using any material.

The liquid receiving means 10 is arranged in a tangential direction,
Moreover, the coating is retracted in the tangential direction at the start of coating, but there is a limit to the shortening of the coating gap in consideration of mechanical accuracy and blurring at this time. As a method of paying attention to this process and eliminating the film thickness nonuniformity,
Although a technique of devising the shape of the liquid receiving means 10 is disclosed in 4, the effect is not sufficiently exerted.

In other words, the conventional arrangement has a limit in shortening the coating gap.

Further, in the case of so-called multi-layer coating, in which at least two layers or more of the coating liquid are laminated on the slide surface 4 to form a thin film coating liquid, and the coating liquid is used for coating, the multi-layer coating is performed. There is a problem in that a contraction flow occurs due to the difference in the surface tension of the coating liquid. As shown in FIG. 14, the contracted flow means that both ends of the coating liquid having a large surface tension among the laminated coating liquids are separated from the side plates or the like provided on the edge guide 6 or the slide surface side end portion, This is a phenomenon in which a uniform multilayer thin film is not formed between the edge guides.

When the contraction flow occurs, the curtain film is very unstable and easily broken, and coating is almost impossible.

As a method for preventing the problem of the contraction, Japanese Utility Model Laid-Open No. 61-75876 discloses a method of covering a curtain edge guide with an auxiliary liquid, Japanese Patent Publication No. 62-47075, Japanese Patent Laid-Open No. 64-144378, and Japanese Patent Laid-Open No. 144378. -293429 describes a method of flowing an auxiliary liquid to the edge of a slide coater surface on which a coating liquid is laminated, and its type.

[0015]

However, the above,
Had the following problems.

The method (1) has an extremely complicated shape for the edge guide for holding the curtain film, and is very difficult to carry out.

The method (1) is to remove the thick film portion after coating, but at this time, it also adversely affects the portion where the thick film is not formed. In addition, since the thick film at both ends is not eliminated in the coating itself, the coating liquid is wasted.

The method (1) is a method in which the liquid receiving means 10 is retracted and coating is started. However, since the coating gap at the start of coating is large, a side thick film is eventually produced. Then, even after the coating gap was shortened, the side thick film was continuously generated.

Also, as for the known technique for preventing the contraction of flow, after the coating liquids are laminated on the slide surface, the both ends of the uppermost coating liquid layer of the laminated thin film coating liquids are assisted. The solution is supplied or the auxiliary solution is supplied to both ends of the thin film-shaped coating solution held by the edge guide, and it does not have a sufficient effect of preventing contraction.

The inventors of the present invention have studied the problems of these conventional examples, and in order to prevent the side thick film from being generated, the coating gap is not only applied during coating but also at the start of coating. Found that is required to be small.

Further, in order to prevent the contraction of flow, it is necessary to make sure that both end portions of the coating liquid laminated on the slide surface are accompanied by the auxiliary liquid, or at least the most of the laminated coating liquids. It was found that contraction does not occur if the auxiliary liquid is allowed to accompany the coating liquid layer having a large surface tension.

Based on these findings, it is an object of the present invention to solve the above-mentioned problems and to eliminate the unevenness of film thickness related to coating, without forcing a significant increase in cost. More specifically, (i) when performing curtain coating, by shortening the coating gap D at both the time of starting coating and the process of coating,
The purpose is to prevent a side thick film, and (ii) to prevent a contracted flow of the laminated thin film-shaped coating liquid regardless of whether it is on the slide surface or between the edge guides.

[0023]

Means for Solving the Problems The present invention includes the following (1)
It is achieved by any of the configurations ( 1 ) to ( 2 ).

(1) A pair of coating liquid is applied to the substrate to be transported.
A device for applying by flowing down the edge guide while propagating between the edge guides.
In the storage, a transport means for transporting the support and at least
Also a slide surface having a predetermined inclination with respect to the horizontal,
Apply a prescribed amount of coating liquid evenly across the width of the slide surface.
Application liquid supply means for supplying and the lowermost end of the slide surface
A pair of edge guides extending downward from the vicinity
At least a first position for applying to the support
And two positions of the second position where the support is not coated.
A coating means that can be placed, and the coating liquid supplied from between the transported support and the edge guide is present on the upstream side in the transport direction with respect to the coating liquid contact portion, which is the position where the coating liquid first contacts.
A movable liquid receiving means, wherein the liquid receiving means is
The horizontal direction of the tangent line of the support in the coating liquid contact part
If it is arranged so that it has a predetermined inclination smaller than the inclination
In both cases, the applying means is configured to receive the liquid at the second position.
Downstream of the coating solution to the means and then applied to the support
To move to the first position for starting
Coating device.

(2) A pair of coating liquid is applied to the substrate to be transported.
A device for applying by flowing down the edge guide while propagating between the edge guides.
In the apparatus, a transport means for transporting the support, at least a slide surface having a predetermined inclination with respect to the horizontal, a plurality of coating liquid supply means for supplying a predetermined amount of coating liquid to the slide surface, both sides of the slide surface A side plate provided at an end and a pair of edge guides provided downwardly extending from the vicinity of the end of the slide surface, and a liquid injection mechanism for supplying an auxiliary liquid from a liquid injection port Have and before
Note that a plurality of coating liquid supply means should be provided on the slide surface at least.
In addition to stacking two or more layers of coating liquid,
Is provided on the side plate, and the slide
An applicator characterized by being in contact with a surface.

[0026]

[0027]

EXAMPLES The present invention will be described below based on examples.

In this embodiment, a photographic film, a photographic light-sensitive material such as photographic paper, a magnetic recording material such as a magnetic tape, a pressure-sensitive paper, etc.
This is an apparatus for applying a coating liquid to a continuously conveyed support in the production of information recording paper such as heat-sensitive paper and other recording materials including photographic printing plate materials.

1 to 8 show a coating apparatus according to the present invention.

FIG. 1 shows a coating apparatus according to the present invention for performing curtain coating on the support 2 in the process of reversing the conveying direction by the backup roller 1. In the present embodiment, the coating is performed in the process of reversing the transport direction, but the support 2 may be transported by the transport rollers 21 and 22 as shown in FIG. In this embodiment, since the coating is performed in the process of being reversed by the backup roller, there is no problem that the support 2 on the upstream side in the transport direction is soiled due to splashing of the coating liquid.

The support 2 is transported by a transport means (not shown). Paper, plastic film, metal, coated paper, or the like is used as the support 2 to be conveyed, and can be appropriately selected in order to obtain a target article to be coated. The backup roller 1 may or may not come into contact with the support 2. In the case of the backup roller 1 that does not come into contact with the support body 2, use an air bag roll that blows fluid such as air through a large number of small holes provided on the roller surface and supports without directly contacting the support body. You can Of course, regarding the type of fluid to be blown,
The liquid is not limited to air, and may be a liquid, and can be appropriately selected as necessary as long as it does not adversely affect the substrate to be transported or the coating liquid.

The coating means 3 includes at least the slide surface 4,
It has a slit 5 which is a supply port of the coating liquid supply means and an edge guide 6, and can be moved between a first position and a second position which will be described later by a moving means (not shown).

The supply port of the coating liquid supply means in this embodiment is a slit 5 provided on the slide surface 4, and the coating liquid is uniformly supplied from the slit 5 in the width direction and flows down the slide surface 4. By doing so, a thin film of the coating liquid is formed. This thin film is applied by flowing down the slide surface 4, propagating between a pair of edge guides 6 provided at both ends of the lower end portion of the slide surface 4, flowing down, and colliding with a support to be conveyed.

Further, the slit 5 for uniformly supplying the coating liquid
A predetermined number can be provided as necessary, and a thin film coating liquid can be laminated by flowing the coating liquid through the plurality of slits 5. FIG. 3 shows a sectional view of the coating means 3 having three slits. As another embodiment of the coating liquid supply means, as shown in FIG. 4, it is also possible to flow down the coating liquid extruded from the extruder 35 onto the slide surface.

The coating liquid separates from the edge guide tip portion 7,
The position where the support 2 collides is the position where the coating starts, and this is referred to as the coating liquid contacting portion P in this specification. This position is a place where the coating liquid is applied to the transported support 2. The position of the coating means 3 that coats the coating liquid contact portion P is referred to as a first position. In the present specification, the state in which the coating means has completely reached the first position is represented by the term “movement completed”.

FIG. 5 shows a perspective view of the coating means 3. Side plates 8 are provided at both ends of the slide surface 4 of the coating means 3, so that the coating liquid supplied from the slit 5 does not flow down from the slide surface side end.
It is regulated. The side plate 8 is provided with a liquid injection port 9. The liquid injection port 9 has a rectangular shape, and one side thereof is in contact with the slide surface. The liquid injection port 9 is connected to a liquid injection mechanism (not shown) so that an auxiliary liquid such as a gelatin solution can be supplied. By supplying the auxiliary liquid from the liquid injection port 9, the coating liquid flowing down on the slide surface 4 flows down along with the auxiliary liquid at the boundary portion with the side plate 8, and the edge guide is directly passed through the auxiliary liquid. It propagates through the space and is applied to the support 2. As a result, when the coating liquid propagating between the edge guides 6 is layered, the contraction flow due to the difference in surface tension as described above does not occur. The size and height of the cross-sectional area of the liquid injection port 9 can be appropriately set to the height at which all layers of the coating liquid flowing down the slide surface come into contact.

FIG. 6 shows an embodiment relating to claim 13 of the present invention. Application means 3 shown in this figure
Then, the liquid injection port 13 is not a small hole provided on the side plate, but the liquid injection port 13 of the nozzle 12 provided at the boundary where the coating liquid flowing down on the slide surface 4 moves between the edge guides 6. It is in the form of supplying supplementary liquid from. Of course, if the coating liquid propagates between the edge guides via the auxiliary liquid, the auxiliary liquid may be supplied on the upstream side of the slide surface with respect to the above-mentioned boundary portion.

The coating means 3 forms a thin film of the coating liquid between the edge guides in a stage before coating the conveyed support. The liquid receiving means 10 is a plate-shaped member for receiving a coating liquid until a stable thin film is formed at this time and coating is started. FIG. 7 shows an example of the liquid receiving means 10. The width L2 is longer than the width L1 between the edge guides and can completely receive the thin film coating liquid supplied from between the edge guides. Side guides 11 are provided at both end portions to prevent the coating liquid flowing down on the liquid receiving means 10 from spilling from both end portions. The coating liquid flowing down on the liquid receiving means 10 is discarded through the discharge port 10A.

The cross-sectional shape of the tip 10B of the liquid receiving means 10 is substantially wedge-shaped as shown in FIGS. In this embodiment, the surface of the liquid receiving means 10 facing the support 2 is formed so as to be a part of a circular arc concentric with the backup roller 1. For this reason, the distance S between the tip of the liquid receiving means 10 and the coating liquid contact portion P is extremely short. This shape is not limited to a part of an arc of a circle concentric with the backup roller 1 as long as the condition that "the distance between the tip of the liquid receiving means and the wetted portion for application" becomes short is satisfied, and a straight line or another curve May be With the liquid receiving means 10 having such a shape and arrangement, the distance S between the liquid contact portion for coating and the tip of the liquid receiving means 10 can be shortened. That is, the distance when the edge guide tip portion 7 moves from the liquid receiving means 10 to the first position is shortened, and the distance S to the coating start portion on the support 2 is shortened.

The material of the liquid receiving means 10 can be appropriately selected from metal, resin, etc., but in this embodiment, a stainless plate having a thickness of 2 mm is used. Further, the shape does not necessarily have to be a flat plate shape, and a curved surface liquid receiving means 10 or the like can be used as appropriate.

When applying, the applying means 3
At the second position, the supply of coating liquid is started.

Here, the second position is a place where the coating means stands by when the coating is not performed, and the edge guide 6 is located on the liquid receiving means 10 at this place. Further, the position where the liquid receiving means 10 is present before the application is started is referred to as a standby position. FIG. 8 is a view of the position of the edge guide when the coating unit is present at the first position and the second position and the position of the liquid receiving unit at the standby position, as viewed from the side surface in the transport direction of the support. The coating means starts to supply the coating solution from the slit 5 which is a supply port of the coating solution supply means on the slide surface 4, and the coating solution formed in a thin film on the slide surface 4 propagates between the edge guides 6. Then run down. Since the coating means 3 is at the second position, the thin film coating liquid is the liquid receiving means.
It flows down 10 and is discharged. Next, the coating means 3 is the first
The coating material is moved to the position and coating is started on the transported support.

In this embodiment, the coating means 3 is moved to the first position after forming a stable thin film of the coating liquid at the second position. However, when the coating means is completely moved to the first position. It suffices that a stable thin film is formed, and this form is not necessarily required. That is, in the process of moving from the second position to the first position, the supply of the coating liquid is started, a stable thin film is formed on the liquid receiving means, and the coating is started at the first position.

As described above, the position where the liquid receiving means 10 is present before the application is started is the standby position. At the standby position, the liquid receiving means 10 is arranged so as to have an inclination smaller than the tangent line of the support 2 at the coating liquid contact portion.

After the start of the coating, the liquid receiving means 10 may remain at the standby position, but when the coating is started (that is, when the coating means is completely moved to the first position and the coating is started at the coating point). ), It is preferable that the liquid receiving means 10 be immediately withdrawn from the standby position. In the present specification, the liquid receiving means 10
Is moved by the term “retract” to move away from the support 2 to be conveyed and the edge guide 6 at the first position and move to a position away from the coating liquid contact part P. Further, in the present specification, the term “completely withdrawing” of the liquid receiving means 10 is represented by the term “withdrawal completed”.
There is no problem with the retreating direction and position of the liquid receiving means 10 as long as it is a direction and position that does not adversely affect the application, such as a type in which the entire liquid receiving means is separated from the backup roller, or a type in which only the liquid receiving tip is separated -It can be selected appropriately. Withdrawing the liquid receiving means from the standby position may cause a problem such that the coating liquid enters or is caught in the upstream side in the transport direction from the gap between the tip of the liquid receiving means and the support 2 to be transported. Disappears. The time from the standby position until the liquid receiving means 10 is completely retracted to a position that does not adversely affect the application is preferably within 1 second, more preferably within 0.5 seconds. If the liquid receiving means is completely retracted within such a short time, the problems such as the infiltration and the entrainment of the coating liquid as described above are eliminated.

The following is a comparison between the examples of the coating apparatus and coating method according to the present invention and the conventional example.

Example 1 Coating was carried out using the coating apparatus shown in FIG. 1 according to claims 1 to 8 of the present invention.

Before starting coating, the liquid receiving means 10 having a plate thickness of 2 mm is placed at the standby position. The shape of the tip portion 10B of the liquid receiving means 10 is processed into a shape along the support 2 to be conveyed. At the standby position, the distance between the coating liquid contact part P and the tip of the liquid receiving means 10 is set to be 4 mm along the transport direction of the support. The coating means starts to supply the thin-film coating liquid to the liquid receiving means 10, and then moves to the first position. The edge guide tip portion 7 is set so that the coating gap D is 1 mm at the first position. Further, the shape of the edge guide tip part 7 is also processed into a shape along the support 2 to be conveyed. After the movement to the first position is completed, the liquid receiving means 10 is completely retracted within 1 second.

(Comparative Example 1) Coating was performed using the conventional liquid receiving means 10D described in Japanese Patent Publication No. 6-24664 and having the shape shown in FIG.

The coating gap before starting coating is set to 30 mm. After supplying the coating liquid to the liquid receiving means 10D and evacuating the liquid receiving means, the coating means 3 was brought close to the support until the coating gap D became 1 mm, and coating was performed.

(Comparative Example 2) Coating was performed using the coating apparatus shown in the partial side views of FIGS. 12 and 13.

Before the start of coating, the liquid receiving means 10E having a plate thickness of 2 mm is arranged in the tangential direction of the coating liquid contact portion P. The coating gap D at this point is 4 mm. First, as shown in FIG. 12, the supply of the coating liquid to the liquid receiving means 10E is started, and when the coating is started, the liquid receiving means is tangentially drawn as shown in FIG.
Evacuate 10E. After the evacuation of the liquid receiving means 10E was completed, the coating means was brought close to the support 2 until the coating gap D became 1 mm, and coating was performed.

(Conditions Common to Each Example) The coating speed (conveying speed of the support) is 300 m / min.

The flow rate of the coating liquid is 5 cc / sec · cm.

The coating solution is an emulsion for photographic light-sensitive materials, which consists of two layers.

The support is polyethylene terephthalate.

The results are shown in Table 1.

[0058]

[Table 1]

The side thick film thickness is a value obtained by measuring the film thickness of both end portions in the transport direction of the coated portion on the support and dividing this thickness by the steady film thickness allowed as a product. is there. The lower this value is, the more the side thick film is prevented from being generated. In this table, the side thick film thickness was measured at both end portions of the coated portion, and the larger value was shown.

As can be seen from the comparison result, by using the coating apparatus and the coating method according to the present invention, the occurrence of the side thick film can be significantly reduced as compared with the conventional technique.
If the coating is performed so that the film thickness is uniform, the following effects can be obtained even in the drying step after the coating.

That is, in the drying step, a drying means such as a dryer dries the coating liquid, but if a coating having a non-uniform film thickness is applied, the drying also becomes non-uniform. As a result, the part coated with an appropriate film thickness is sufficiently dried, the part where the thick film is formed is not sufficiently dried, and the undried coating liquid adheres when the support is wound. However, there are inconveniences such as soiling the support. On the other hand, if the coating apparatus according to the present invention is used, the side thick film can be effectively reduced, so that the above-mentioned problems relating to drying can be solved.

As a result, the load on the drying means such as a drier is reduced, or the drying process itself is shortened, and the degree of freedom in designing the coating / drying system is increased.

(Embodiment 2) Next, the tenth aspect of the present invention will be described.
The coating device relating to 13 will be described.

Using the coating means shown in FIG. 5, multi-layer coating was carried out by superposing two kinds of coating solutions on the slide surface.
Auxiliary liquid was made to flow from the liquid injection port so that the auxiliary liquid would flow along both ends of the coating liquid flowing down the slide surface. The injection port is in contact with the slide surface, and the opening area is 1 mm ² .

Comparative Example 3 Coating was carried out under the same conditions as above, but without supplying the auxiliary liquid.

The common conditions are as follows.

Surface tension of the upper layer of the coating liquid 33 dyn / cm Surface tension of the lower layer of the coating liquid 45 dyn / cm Flow rate of the coating liquid 1.4 cc / cm · s Coating speed (conveying speed of the support) 70 m / min Auxiliary liquid is 1% by weight Gelatin solution Flow rate 10 cc / min Surface tension 48 dyn / cm The results are shown in Table 2 below.

[0068]

[Table 2]

(Example 3) Using the coating means shown in FIG. 6, multi-layer coating was carried out by superimposing seven kinds of photographic light-sensitive materials on the slide surface. The auxiliary liquid was made to flow from the liquid injection port so that the auxiliary liquid would flow along with the side end portion of the coating liquid. The injection port was provided at a position 3 mm above the edge guide from the point where the coating solution moves from the slide surface to the edge guide.

Comparative Example 4 Coating was carried out under the same conditions as above, but without supplying the auxiliary liquid.

The common conditions are as follows.

Flow rate of coating liquid 2.5 cc / cm · s Coating speed (conveying speed of support) 200 m / min Auxiliary liquid is 1% by weight gelatin solution Flow rate 10 cc / min (5 per side)
cc / min) Surface tension of auxiliary liquid 48 dyn / cm The results are shown in Table 3 below.

[0073]

[Table 3]

(Example 4) Coating was carried out by using a coating apparatus in which the coating apparatus of Example 1 and the coating apparatus of Example 2 were combined.

The coating conditions are exactly the same as in Example 1.

Auxiliary liquid was supplied from the injection port. Auxiliary liquid conditions and supply conditions are the same as in Example 3.

(Comparative Example 5) The auxiliary liquid was supplied without being supplied.

The results are shown in Table 4 below.

[0079]

[Table 4]

As can be seen from the comparison result, the use of the coating apparatus according to the present invention can significantly reduce the occurrence of the side thick film as compared with the prior art, and in the drying step which is the next step of the coating step. Also, the load on the drying means such as a dryer is reduced, or the drying process itself is shortened, and the degree of freedom in designing the coating / drying system is increased.

Further, in the case of a coating liquid having a viscosity of more than 40 cp, the formation of side thick film can be further reduced by combining two coating devices as in this embodiment. .

[0082]

As described above, according to the first aspect of the present invention, when performing curtain coating, the gap between the tip of the curtain edge guide and the support to be coated is greatly shortened as compared with the prior art. Therefore, a so-called side thick film is not generated. Further, even in the drying step subsequent to the coating step, since excessive drying for drying the thick film portion is not required, the load on the drying means such as a drier is reduced, and as a result, the drying step is shortened, the drier, etc. The capacity of the drying means can be reduced, and the production cost can be reduced. In addition, since the device can be manufactured without adding a large amount of modification or improvement to the conventional coating device, the production cost can be similarly reduced.

According to the invention of claim 2 of the present application, since the shape of the tip end portion of the edge guide is a shape that conforms to the support to be conveyed, it is possible to shorten the gap in which both edges of the curtain film are not bound by anything. The side thick film can be prevented.

According to the invention of claim 3 of the present application, the distance between the tip of the edge guide and the support is larger than 0 mm and 5 mm or less, so that the gap between both edges of the curtain film is not restricted by anything. Therefore, the thick side film can be prevented.

According to the invention of claim 4 of the present application, the cross-sectional shape of the tip of the liquid receiving means is substantially wedge-shaped toward the downstream side in the carrying direction when viewed from the direction perpendicular to the carrying direction of the support. The gap between the edge guide tip of the receiving means and the gap between the liquid receiving means and the support can be shortened, and the edge guide tip when the curtain film-shaped coating liquid moves from the liquid receiving means onto the support can be shortened. The gap with the support can be made small (the coating gap can be shortened), and the side thick film at the start of coating can be suppressed.

According to the invention of claim 5 of the present application, the distance between the end of the edge guide on the side facing the liquid receiving means and the tip of the liquid receiving means is greater than 0 mm and 8 mm or less.
When the curtain film-shaped coating liquid moves from the liquid receiving means onto the support, the gap between the edge guide tip and the support can be made small (the coating gap can be shortened), and the side thick film at the start of coating can be suppressed. You can

According to the sixth aspect of the present invention, the curtain film is formed at a place other than the first position, and then the coating means moves to the first position to start coating on the support. There is no waste of.

According to the invention of claim 7 of the present application, since the liquid receiving means is withdrawn after the movement of the coating means to the first position is completed, the curtain-shaped coating liquid is conveyed from the tip of the liquid receiving means to the support. It does not adversely affect the support immediately before the application point by sneaking in or being caught in the upstream side in the direction.

According to the invention of claim 8 of the present application, since the time from the completion of the movement of the coating means to the first position to the withdrawal of the liquid receiving means is within 1 second, the curtain-shaped coating liquid receives the liquid. There is almost no adverse effect on the support immediately before the coating point by penetrating from the tip of the means to the upstream side in the transport direction of the support, and there is little waste in the coating start portion of the support.

According to the invention of claim 9 of the present application, since there are few areas on the support where the coating is not properly applied, the productivity can be improved and the cost can be reduced.

According to the invention of claim 10 of the present application,
In the coating liquid formed in a curtain shape between the edge guides, it is possible to prevent contraction even if there is a large difference in the surface tension of the coating liquid of each layer. It can be applied. Furthermore, since the liquid injection port is in contact with the slide surface, the auxiliary liquid can be surely accompanied by the side end portion of the coating liquid to be laminated on the slide surface, and the layers can be sequentially laminated. As a result, even when there is a large difference in the surface tension between the laminated coating solutions, there is no contraction flow not only on the slide surface but also in the curtain shape where both ends are held by the edge guides, and stable coating is possible. It is possible.

According to the eleventh aspect of the present invention, since the liquid injection port is located upstream of the coating liquid laminated on the slide surface,
If the auxiliary liquid is supplied from the liquid injection port and then the coating liquid is supplied from the slit, it is possible to reliably accompany all the laminated coating liquids, so that the coating liquid propagates between the edge guides and flows down. Stable application is possible without the occurrence of contraction in the state of a circle.

According to the twelfth aspect of the present invention, since the liquid injection port is located on the downstream side of the slide surface with respect to the slit for supplying the coating liquid, after all the coating liquids are laminated on the sliding surface,
Since the auxiliary liquid from the pouring port can be made to accompany all laminated coating liquids reliably, stable coating is possible without contraction in the curtain-like state where both ends are held by the edge guides. Is.

[0094]

According to the thirteenth aspect of the present invention, a stable photosensitive material having a large coating area can be obtained even with a coating solution in which coating solutions having different surface tensions are laminated.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of a coating apparatus of the present invention.

FIG. 2 is a side view showing another embodiment of the conveyance path of the support.

FIG. 3 is a cross-sectional view of a coating means showing a slide surface provided with three slits.

FIG. 4 is a side view showing a slide surface to which a coating liquid is supplied by an extruder.

FIG. 5 is a perspective view of an application unit in which a side plate is provided with a liquid injection port.

FIG. 6 is a perspective view of an application unit in which a liquid injection port is provided above a boundary portion of a lower end of a slide surface.

FIG. 7 is a perspective view of a liquid receiving means.

FIG. 8 is a partially enlarged view of the vicinity of the coating liquid contact portion.

FIG. 9 is a perspective view of a curtain coating device.

FIG. 10 is a front view showing the behavior of the curtain film between coating gaps.

FIG. 11 is a front cross-sectional view of a support having a side thick film.

FIG. 12 is a partial side view of a conventional coating device showing the relationship between the liquid receiving means and the edge guide before the start of coating.

FIG. 13 is a partial side view of a conventional coating device showing the relationship between the liquid receiving means and the edge guide after the start of coating.

FIG. 14 is a diagram showing a state in which the coating liquid propagating between the edge guides is contracting.

FIG. 15 is a partial side cross-sectional view of a coating device equipped with an example of conventional liquid receiving means.

[Explanation of symbols]

1 Backup roller 2 support 3 Application means 4 Slide surface 5 slits 6 Edge guide 7 Edge guide tip 8 side plates 9 Injection port 10 Liquid receiving means 11 Side guide 12 Injection nozzle P coating wetted part 13 Injection port

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B05C 5/00 G03C 1/74

Claims (13)

(57) [Claims] 1. An apparatus for applying a coating liquid to a substrate to be conveyed by flowing it down while propagating between a pair of edge guides, and a conveying means for conveying the substrate, and at least a predetermined horizontal direction. A slidable slide surface, a coating liquid supply means for uniformly supplying a predetermined amount of coating liquid in the width direction of the slide surface, and a pair of downwardly extending from the vicinity of the lowermost end of the slide surface. An edge guide, at least a first position for applying the support and a second position for not applying the support.
A coating means that can take any kind of position, and a movement that is present on the upstream side in the transport direction with respect to the coating liquid contact part that is the position where the coating liquid supplied from between the transported support and edge guide first contacts. have a possible liquid receiving means
Then, the liquid receiving means is arranged so as to have a predetermined inclination smaller than the inclination of the tangent line of the support in the coating liquid contact portion with respect to the horizontal direction , and
Following the flow of the coating liquid to the liquid receiving means at the position 2
Move to the first position to start coating on the support
Coating apparatus characterized by dynamic. 2. The coating apparatus according to claim 1, wherein a shape of a tip end portion of the edge guide on a side opposite to a side provided on the slide surface is a shape along the transported support body. A coating device characterized by the above. 3. The coating apparatus according to claim 1, wherein when the coating unit is in the first position, a tip portion of the edge guide opposite to a side provided on the slide surface, The coating device is characterized in that the distance to the conveyed support is larger than 0 mm and smaller than 5 mm. 4. The coating apparatus according to claim 1, wherein an end portion of the liquid receiving means facing the edge guide has a substantially wedge shape. . 5. The coating device according to any one of claims 1 to 4, wherein when the coating means is in the first position and the liquid receiving means is in the standby position, the slide surface of the edge guide is formed. The coating device is characterized in that the distance between the tip end on the side opposite to the one provided on the side and the tip end of the liquid receiving means at the standby position is larger than 0 mm and smaller than 8 mm. 6. The coating apparatus according to claim 1, wherein the coating unit is controlled to move to the first position after starting the supply of the coating liquid to the liquid receiving unit. A coating device characterized by the above. 7. The coating apparatus according to claim 1, wherein after the coating means has completed moving to the first position,
An application device, wherein the liquid receiving means is retracted from the standby position. 8. The coating apparatus according to any one of claims 1 to 7, wherein after the coating means has completed moving to the first position, the time required for the liquid receiving means to complete withdrawal from the standby position is A coating device characterized by being within 1 second. 9. A photosensitive material manufactured by using the coating apparatus according to claim 1. 10. An apparatus for applying a coating solution to a transported support by flowing it down while propagating between a pair of edge guides and applying the coating solution, at least a transport means for transporting the support, and a predetermined horizontal direction. An inclined slide surface, a plurality of coating liquid supply means for supplying a predetermined amount of coating liquid to the slide surface, side plates provided at both end portions of the slide surface, and extending downward from the vicinity of the end portion of the slide surface A pair of edge guides that are provided together, and a liquid injection mechanism that supplies auxiliary liquid from the liquid injection port, and the plurality of application liquid supply devices are provided on the slide surface.
Both are two or more layers of coating liquid laminated, and the liquid injection port is provided in the side plate and is in contact with the slide surface. 11. The coating apparatus according to claim 10,
The coating device, wherein the liquid injection port is provided on the upstream side of all the coating liquid supply means in the direction in which the coating liquid flows on the slide surface. 12. The coating apparatus according to claim 10,
The coating apparatus, wherein the liquid injection port is provided on the downstream side of all the coating liquid supply means in the flowing direction of the coating liquid on the slide surface. 13. A photosensitive material produced by using the coating apparatus according to any one of claims 10 to 12 .