JPH10202157A - Slide application device and manufacture of photosensitive material using this device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to apply a coat uniformly without generating an undulation phenomenon by providing at least, a single slit which gradually widens a gap smoothly from the innermost to a slide face, in a slide application device which concurrently applies two or more layers on a continuously travelling support. SOLUTION: In an application device capable of concurrently applying three layers, coating liquids 13-15 reach a slide face 5 passing through each of slits 4, then arrive at the tip 6 of the application device after flowing down the slide face 5 and are applied to the surface of a support web 10 through a bead 12. In this case, the outlet side of each of the slits 4 is formed in such a manner that the outlet on the downstream side comes into contact moderately with the slide face 5, and the outlet on the upstream side is almost at right angles with the slide face 5. Consequently, a liquid turbulence due to a collision between the coating liquids 13-15 on the outlet side of each of the slits 4 is inhibited. In addition, a discharge pressure to be generated when the coating liquids 13-15 flow out of each of the slit 4 outlets to the slide face 5 is mitigated by provided providing an enlarged part at each of the slit 4 outlets.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slide bead coating apparatus or a curtain coating apparatus having a slide surface for simultaneously coating a plurality of coating liquids in multiple layers, and a method for producing a photosensitive material using the coating apparatus.

[0002]

2. Description of the Related Art In a slide coating, if two or more layers are simultaneously coated, a ripple phenomenon easily occurs on the slide surface with an increase in the number of liquid-liquid interfaces and a flowing distance. As a result, there may be a difference in the layer thickness between the layers at each position in the coating direction, which may cause color unevenness in the coated sample. In order to solve this problem, conventionally, as disclosed in Japanese Patent Application Laid-Open No. 3-219237, the problem has been addressed by increasing the viscosity of the coating solution. The flow rate is restricted, and productivity decreases.

In addition, if the defoaming is incomplete, bubbles will stagnate at the slit outlet of the slide hopper, leading to the occurrence of muscle failure. Therefore, as disclosed in US Pat. No. 3,474,758, Although the gap distance between the passages of the slits of the hopper is made constant so as to be parallel to the slide surface so as to match the slide surface, a sufficient effect has not been obtained.

Further, Japanese Patent Application Laid-Open No. 4-328174 discloses that the gap distance of a slit near an exit to a slide surface is made larger than the gap distance of an upstream slit to reduce the waving phenomenon. It was not enough.

[0005]

The color photographic material which has been developed recently has a coating solution of 15 layers, and it has to be applied several times even though it is a multilayer coating. The occurrence of static electricity, scratches, and pressure fogging due to friction between the roller and the roller caused a decrease in yield (rate of non-defective products) and a significant decrease in production efficiency.

According to the present invention, even if the viscosity is low, no waving phenomenon occurs, and even if the liquid has a large pseudoplasticity and the viscosity decreases when passing through a slit, a uniform coated sample free from waving phenomenon can be obtained. A slide coating apparatus that does not cause color unevenness or streak failure, and that can perform simultaneous multi-layer coating of at least seven or more layers, and that can be completed in a single coating even in multi-layer coating of photosensitive materials over the present and future. It is an object of the present invention to provide a method for producing a used photosensitive material and to improve production yield (non-defective rate) and production efficiency.

[0007]

This object is achieved by any one of the following technical means (1) to (6).

(1) A slide coating apparatus for simultaneously coating two or more layers on a continuously running support, characterized in that the slide coating apparatus has at least one slit in which the gap is smoothly increased from the inside to the slide surface. Slide coating device.

(2) The slide according to (1), wherein the downstream side of the slit on the slide surface in the liquid flow direction has a curvature in contact with the slide surface, and the upstream side has a substantially straight shape on the slide surface. Coating device.

(3) The slide coating apparatus according to item (2), wherein the downstream-side curvature of the slit has a uniform radius of curvature.

(4) Any one of the above items (1) to (3)
A method for producing a photosensitive material, characterized by using the slide coating device described in the above section.

(5) The method for producing a photosensitive material as described in (4), wherein seven or more layers are simultaneously coated.

(6) The method for producing a photosensitive material as described in the above item (4) or (5), wherein the coating is performed using a pseudoplastic liquid.

The inventor of the present invention provided an enlarged portion in a slit for guiding a coating solution onto a slide surface of a slide coater, and gradually and gradually widened the gap between the slits, so that a wavy phenomenon occurred when a liquid-liquid interface was formed. I have found that it can be suppressed. The waving phenomenon is likely to occur when the viscosity at the time of forming the liquid and liquid-liquid interface of the upper layer in the slit portion is low, and is amplified as the time until application to the support becomes longer thereafter, as described above. By forming the slit enlarged portion in a curved shape, a wavy phenomenon does not occur even in a liquid having a large pseudoplasticity and a reduced viscosity when passing through the slit. Therefore, a uniform coated sample without color unevenness can be obtained. In addition, foreign substances and bubbles adhere to the slit portion, and streaks are generated, which has been a problem as a serious coating failure. However, by using this apparatus, the muscle failure due to the adhesion of foreign substances and bubbles has been resolved. .

Providing the enlarged portion in the slit and widening the gap smoothly means that the liquid passage gap g is defined as g = f by a distance x between the slit portion and the slide surface through the enlarged portion.
When expressed as (x), it means that the first derivative of g is continuous.

The liquid having pseudoplasticity has such a property that a large apparent viscosity is exhibited when the shear rate is low, and the viscosity decreases when the shear rate is increased.

Hereinafter, the present invention will be described specifically.

FIG. 1A shows a slide bead coating apparatus 1.
It is sectional drawing which shows an example, and is a coating device which can apply | coat three layers simultaneously. In the figure, a plurality of coating liquids 13, 14, 15
Reaches the slide surface 5 through the slit 4 extending in the gap direction, the coating liquid flows down the slide surface to reach the tip (lip) 6 of the coating machine, where it is held on the backup roller 1 via a liquid pool called a bead 12. It is applied onto a carrier web 10 which is run in motion. 3 in the figure is a decompression device,
The bead is stabilized by pulling the bead downward.

FIG. 1A shows the case of three layers, but when more than 15 layers are simultaneously coated, the number of coating blocks may be increased. Accordingly, the number of slits becomes 15 or more, the number of slide surfaces increases, and the amount of liquid overlap increases.

Therefore, the number of superposed layers of the coating liquid on the slide surface increases gradually from the upstream side, and at the most downstream (slide surface near the lip), 15 or more liquid layers are overlapped.
For this reason, turbulence and waving between liquid layers are likely to occur.

FIG. 1B shows a state in which the coating liquids A, B and C flowing out of the slits overlap on the slide surface.
As is clear from the drawing, the coating solution on the upstream side, for example, A, flows over the coating solution B on the downstream side and further over B and C while forming a layer.

As a result of intensive studies, the present inventors have found that the state in which the coating solution flows out of the slit onto the slide surface is improved, and that the turbulence and wavyness between the liquid layers are greatly reduced.

FIG. 2A is an enlarged sectional view showing the shape of each slit on the exit side. The downstream shape has a radius of curvature R of 3
６6 mm, smoothly contacting the slide surface 5, the shape on the upstream side is substantially perpendicular to the slide surface 5, and the straight state is maintained.

With such a structure, liquid disturbance due to collision between the coating liquids at the slit outlet can be suppressed.

The slit gap can be set arbitrarily in the range of 50 to 1000 μm.

In the present invention, the slit is provided with an enlarged portion of the gap in order to guide the coating solution onto the slide surface.

In the present invention, by providing the above-described enlarged portion at the slit outlet, the discharge pressure when the coating liquid flows out from the slit outlet to the slide surface is reduced, and the disturbance of the coating liquid from the upstream is suppressed. . According to the study of the present inventors, there is a difference in the pressure distribution near the slit exit due to the shape of the slit, and by providing the enlarged portion in the slit, the pressure distribution becomes uniform, thereby suppressing the waving. Was found. Further, specifically, R is preferably 3 to 8 mm, and particularly, 4 to 6 mm, the effect becomes remarkable as shown in the examples described later.

FIG. 2B is a sectional view showing an example of the outlet shape of the enlarged portion of the slit having the inclined surface.
(C) is a sectional view showing an example of a rectangular enlarged portion.

The enlarged portion in FIG. 2A may have the same radius of curvature R for each slit or may be different. For example, the radius of curvature R can be set larger as it goes downstream, or conversely, the radius of curvature R can be made larger as it goes upstream.

When the coating solution flowing on the slide surface comes into contact with the web via the bead, the influence of the inclination angle α of the slide surface with respect to the horizontal reference plane is also important.

The undulation phenomenon is mainly controlled by the coating liquid film thickness (flow rate) on the slide surface and the flow time at the liquid-liquid interface.
In the present invention, the inclination angle α is preferably 5 to 30 °, more preferably 5 to 25 °, and most preferably 10 to 20 °. If it is 5 ° or less, the falling time becomes long, and if it is 30 ° or more, the flowing liquid film thickness becomes small, and the waving phenomenon tends to occur.

Further, in the present invention, the flow rate at the slit outlet in all coating layers is 0.1 cc / cm. se
It is preferably at least c.

The coating speed in the present invention is from 30 to 600.
It is set in the range of m / min. Preferably, 40 to 4
00 m / min, more preferably 60 to 250 m / mi
A speed of n is employed.

The support used in the present invention is a transparent support such as polyethylene terephthalate and triacetyl cellulose, a reflective support such as polyethylene laminated paper, and is not limited to a specific support.

[0035]

EXAMPLES The effects of the present invention will now be specifically illustrated by examples.

With respect to the coating layer in the present invention, the following 3
Layer, 8 and 15 layer formulations were used.

[0037] The addition amount of the composition exhibit particularly grams per 1 m ² unless otherwise noted. Silver halide and colloidal silver are shown in terms of silver. The sensitizing dye was represented by the number of moles per mole of silver halide.

The viscosity was adjusted with an aqueous solution thickener containing styrene and a maleic acid sodium salt copolymer as main components.

(Three-layer formulation) First layer: Antihalation layer Black colloidal silver 0.16 Ultraviolet absorber (UV-1) 0.20 High boiling solvent (Oil-1) 0.16 Gelatin 1.23 Second layer : Intermediate layer Compound (SC-1) 0.15 High boiling point solvent (Oil-2) 0.17 Gelatin 1.27 Third layer: Red-sensitive layer Silver iodobromide emulsion (average grain size 0.38 μm, silver iodide 0.50 silver iodobromide emulsion (average grain size 0.27 μm, silver iodide content 2.0 mol%) 0.21 sensitizing dye (SD-1) 2.8 × 10 ^-4 sensitizing dye (SD-2) 1.9 x 10 ^-4 sensitizing dye (SD-3) 1.9 x 10 ^-5 sensitizing dye (SD-4) 1.0 x 10 ^-4 cyan coupler (C-1) 0.48 Cyan coupler (C-2) 0.14 Colored cyan coupler (CC-1) 0.021 DIRization Product (D-1) 0.020 High boiling point solvent (Oil-1) 0.53 Gelatin 1.30 (8 layer formulation) First layer: Anti-halation layer Black colloidal silver 0.16 Ultraviolet absorber (UV-1) 0.20 High boiling solvent (Oil-1) 0.16 Gelatin 1.23 Second layer: Intermediate layer Compound (SC-1) 0.15 High boiling solvent (Oil-2) 0.17 Gelatin 1.27 Third Layer: Red-sensitive layer Silver iodobromide emulsion (average particle size 0.38 μm, silver iodide content 8.0 mol%) 0.50 Silver iodobromide emulsion (average particle size 0.27 μm, silver iodide content) 2.01 mol%) 0.21 sensitizing dye (SD-1) 2.8 × 10 ^-4 sensitizing dye (SD-2) 1.9 × 10 ^-4 sensitizing dye (SD-3) 1.9 × 10 ^-5 sensitizing dye (SD-4) 1.0 × 10 ^-4 cyan coupler (C-1) 0.48 cyan coupler (C-2) 0.14 Colored cyan coupler (CC-1) 0.021 DIR compound (D-1) 0.020 High boiling point solvent (Oil-1) 0.53 Gelatin 1.30 Fourth layer: Intermediate layer Compound (SC-1) 0.09 High-boiling point solvent (Oil-2) 0.11 Gelatin 0.80 Fifth layer: green-sensitive layer Silver iodobromide emulsion (average grain size: 0.38 μm, silver iodide content: 8.0 mol%) 0.61 silver iodobromide emulsion (average particle size 0.27 μm, silver iodide content 2.0 mol%) 0.20 sensitizing dye (SD-4) 7.4 × 10 ^-5 sensitizing dye (SD -5) 6.6 × 10 ^-4 Magenta coupler (M-1) 0.18 Magenta coupler (M-2) 0.44 Colored magenta coupler (CM-1) 0.12 High boiling solvent (Oil-2) 0 0.75 gelatin 1.95 6th layer: yellow filter layer yellow colloidal silver 0.08 Color stain inhibitor (SC-2) 0.15 Formalin scavenger (HS-1) 0.20 High boiling solvent (Oil-2) 0.19 Gelatin 1.10 7th layer: Blue-sensitive layer Iodobromide Silver emulsion (average grain size: 0.38 μm, silver iodide content: 8.0 mol%) 0.22 Silver iodobromide emulsion (average grain size: 0.27 μm, silver iodide content: 2.0 mol%) 03 sensitizing dye (SD-9) 4.2 × 10 ^-4 sensitizing dye (SD-10) 6.8 × 10 ^-5 yellow coupler (Y-1) 0.75 DIR compound (D-1) 010 High boiling point solvent (Oil-2) 0.30 Gelatin 1.20 Eighth layer: protective layer Silver iodobromide emulsion (average particle size 0.08 μm, silver iodide content 1.0 mol%) 0.40 Ultraviolet light Absorbent (UV-1) 0.026 Ultraviolet absorber (UV-2) 0.013 High boiling solvent (Oil-1) 0.07 High boiling point solvent (Oil-3) 0.07 Formalin scavenger (HS-1) 0.40 Gelatin 1.31 Alkali-soluble matting agent (average particle size 2 μm) 0.15 Polymethyl methacrylate (average particle size 3 μm) 0.04 Slip agent (WAX-1) 0.04 Gelatin 0.55 Su-1 0.02 Su-2 0.03 H-1 0.024 H-5 0.046 H-9 0.010 (15 layers Prescription) First layer: Antihalation layer Black colloidal silver 0.16 Ultraviolet absorber (UV-1) 0.20 High boiling solvent (Oil-1) 0.16 Gelatin 1.23 Second layer: Intermediate layer Compound (SC) -1) 0.15 High-boiling point solvent (Oil-2) 0.17 Gelatin 1.27 Third layer: low-sensitivity (first) red-sensitive layer Silver iodobromide emulsion (average grain size 0.38 μm, silver iodide Content of 8.0 0.50 silver iodobromide emulsion (average particle size 0.27 μm, silver iodide content 2.0 mol%) 0.21 sensitizing dye (SD-1) 2.8 × 10 ⁻⁴ sensitization Dye (SD-2) 1.9 × 10 ^-4 sensitizing dye (SD-3) 1.9 × 10 ^-5 sensitizing dye (SD-4) 1.0 × 10 ^-4 cyan coupler (C-1) 0.48 Cyan coupler (C-2) 0.14 Colored cyan coupler (CC-1) 0.021 DIR compound (D-1) 0.020 High boiling solvent (Oil-1) 0.53 Gelatin 1.30 Four layers: middle-sensitivity (second) red-sensitive layer Silver iodobromide emulsion (average particle size 0.52 μm, silver iodide content 8.0 mol%) 0.62 Silver iodobromide emulsion (average particle size 0. 38 μm, silver iodide content: 8.0 mol%) 0.27 sensitizing dye (SD-1) 2.3 × 10 ^-4 sensitizing dye (SD-2) 1.2 × 10 ^-4 sensitizing color Element (SD-3) 1.6 × 10 ^-5 sensitizing dye (SD-4) 1.2 × 10 ^-4 cyan coupler (C-1) 0.15 cyan coupler (C-2) 0.18 colored cyan Coupler (CC-1) 0.030 DIR compound (D-1) 0.013 High boiling solvent (Oil-1) 0.30 Gelatin 0.93 Fifth layer: high sensitivity (third) red-sensitive layer iodobromide Silver emulsion (average particle size: 1.00 μm, silver iodide content: 8.0 mol%) 1.27 Cyan coupler (C-2) 0.12 Colored cyan coupler (CC-1) 0.013 High boiling solvent (Oil) -1) 0.14 gelatin 0.91 6th layer: intermediate layer Compound (SC-1) 0.09 high boiling point solvent (Oil-2) 0.11 gelatin 0.80 7th layer: low sensitivity (first) Green-sensitive layer Silver iodobromide emulsion (average grain size 0.38 μm, silver iodide content 8.0) Le%) 0.61 Silver iodobromide emulsion (average particle diameter 0.27 [mu] m, silver iodide content 2.0 mol%) 0.20 Sensitizing dye (SD-4) 7.4 × 10 -5 sensitization Dye (SD-5) 6.6 × 10 ^-4 Magenta coupler (M-1) 0.18 Magenta coupler (M-2) 0.44 Colored magenta coupler (CM-1) 0.12 High boiling solvent (Oil- 2) 0.75 gelatin 1.95 8th layer: medium-sensitivity (second) green-sensitive layer silver iodobromide emulsion (average grain size 0.59 μm, silver iodide content 8.0 mol%) increased by 0.87 Sensitizing dye (SD-6) 1.6 × 10 ^-4 sensitizing dye (SD-7) 1.6 × 10 ^-4 sensitizing dye (SD-8) 1.6 × 10 ^-4 Magenta coupler (M-1) ) 0.058 Magenta coupler (M-2) 0.13 Colored magenta coupler (CM-2) 0.070 DIR compound (D-2) 0.025 DIR compound (D-3) 0.002 High boiling point solvent (Oil-2) 0.50 Gelatin 1.00 Ninth layer: High sensitivity (third) green-sensitive layer Silver iodobromide emulsion (Average particle size) 1.00 μm, silver iodide content: 8.0 mol%) 1.27 Sensitizing dye (SD-6) 9.4 × 10 ^-5 Sensitizing dye (SD-7) 9.4 × 10 ^-5 sensitizing Dye (SD-8) 9.4 × 10 ^-5 Magenta coupler (M-2) 0.084 Magenta coupler (M-3) 0.064 Colored magenta coupler (CM-2) 0.012 High boiling solvent (Oil- 1) 0.27 High boiling point solvent (Oil-2) 0.012 Gelatin 1.00 10th layer: Yellow filter layer Yellow colloidal silver 0.08 Color stain inhibitor (SC-2) 0.15 Formalin scavenger (HS-) 1) 0.20 High boiling point solvent (Oil-2) 0 .19 gelatin 1.10 eleventh layer: low-sensitivity (first) blue-sensitive layer silver iodobromide emulsion (average grain size: 0.38 μm, silver iodide content: 8.0 mol%) 0.22 silver iodobromide Emulsion (average particle size 0.27 μm, silver iodide content 2.0 mol%) 0.03 sensitizing dye (SD-9) 4.2 × 10 ^-4 sensitizing dye (SD-10) 6.8 × ^10-5 yellow coupler (Y-1) 0.75 DIR compound (D-1) 0.010 high boiling point solvent (Oil-2) 0.30 gelatin 1.20 12th layer: medium sensitivity (second) blue sensitivity Layer Silver iodobromide emulsion (average particle size 0.59 μm, silver iodide content 8.0 mol%) 0.30 sensitizing dye (SD-9) 1.6 × 10 ^-4 sensitizing dye (SD-11) ) 7.2 × 10 ^-5 Yellow coupler (Y-1) 0.10 DIR compound (D-1) 0.010 High boiling solvent (Oil-2) 0.046 Ratine 0.47 13th layer: high-sensitivity (third) blue-sensitive layer Silver iodobromide emulsion (average grain size: 1.00 μm, silver iodide content: 8.0 mol%) 0.85 sensitizing dye (SD- 9) 7.3 × 10 ^-5 sensitizing dye (SD-11) 2.8 × 10 ^-5 yellow coupler (Y-1) 0.11 high boiling solvent (Oil-2) 0.046 gelatin 0.80 14 layers: first protective layer Silver iodobromide emulsion (average particle size 0.08 μm, silver iodide content 1.0 mol%) 0.40 UV absorber (UV-1) 0.026 UV absorber (UV -2) 0.013 High boiling solvent (Oil-1) 0.07 High boiling solvent (Oil-3) 0.07 Formalin scavenger (HS-1) 0.40 Gelatin 1.31 15th layer: 2nd protective layer Alkali-soluble matting agent (average particle size 2 μm) 0.15 polymethyl methacrylate (flat 0.04 Slip agent (WAX-1) 0.04 Gelatin 0.55 Su-1 0.02 Su-2 0.03 H-1 0.024 H-5 0.046 H-9 010

[0040]

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[0041]

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[0042]

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[0043]

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[0044]

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[0045]

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[0046]

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[0047]

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[0048]

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[0049]

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Using the coating solution having such a formulation, the coating apparatus shown in FIG. 1 was used to apply a coating speed of 100 m / m to a support web made of triacetyl cellulose and having a thickness of 120 μm.
In the first embodiment, as a slit enlarged portion, type 1 shown in FIG. 2A (however, R is limited to 4 mm), type 2 shown in FIG. 2B, and FIG. The type 3 was used for comparison, and the ripples on the slide surface and the occurrence of streaks were evaluated. In Example 2, the radius of curvature R of the slit enlarged portion was changed to a range of 1 to 8 mm to reduce the ripples on the slide surface. The state of occurrence of streaks was evaluated.

Criteria for evaluating the occurrence of waviness The viscosity of each layer was uniformly adjusted to 20 cp, and coating was performed by slide bead coating. However, since evaluation was not possible on the slide surface, the coated sample was developed and the intensity of occurrence of color unevenness was evaluated. Was evaluated.

Evaluation criteria for color unevenness ：: No occurrence △: Slight occurrence No problem in practical use ×: Strong occurrence Evaluation criteria for streak generation Foreign matter was forcibly adhered to the enlarged portion of the slit, and the streak strength of the applied sample was evaluated. evaluate.

The foreign matter has a thickness of 150 μm at each part shown in FIG.
m, a tape of 2 mm × 2 mm in size was stuck. The generation strength standard of the streak strength was as follows.

：: No occurrence Δ: Broad streak occurred X: Sharp streak occurred The result of Example 1 is as shown in Table 1.

[0055]

[Table 1]

By forming the slit enlarged portion into a curved shape as in Type 1, both the undulation and the streak were extremely improved.

Table 2 shows the results of Example 2.

[0058]

[Table 2]

The radius of curvature R of the enlarged slit portion is 4 to 6 mm.
Is very desirable.

[0060]

According to the present invention, it is possible to obtain a uniform coating sample which does not cause waving even at a low viscosity in a multi-layer coating, and which does not cause waving even in a liquid having high pseudoplasticity and a reduced viscosity when passing through a slit. And also
This has made it possible to eliminate color unevenness due to ripples and to prevent occurrence of streak failure.

As a result, simultaneous application of seven or more layers becomes possible, so that the conventional method of applying the desired number of layers in two or more applications can be performed only once, and the guide roller is passed again after the second application. As a result, there is no fear of fogging failure due to frictional electrification and the like, and the production efficiency and product yield are greatly improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an application state by a slide application apparatus of the present invention.

FIG. 2 is a cross-sectional view showing each type of an enlarged slit portion of the slide coating device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 backup roller 2 slide coating device 4 slit 5 slide surface 6 lip 10 support web 12 bead 13, 14, 15 coating liquid R enlarged portion radius of curvature

Claims (6)

[Claims] 1. A slide coating apparatus for simultaneously coating two or more layers on a continuously running support, wherein the slide has at least one slit in which the gap is smoothly increased from the inside to the slide surface. Coating device. 2. The slide coating apparatus according to claim 1, wherein the downstream side of the slit on the slide surface in the liquid flow direction has a curvature in contact with the slide surface, and the upstream side has a substantially straight shape on the slide surface. . 3. The slide coating device according to claim 2, wherein the downstream-side curvature of the slit according to claim 2 has a uniform radius of curvature. 4. A method for producing a photosensitive material, comprising using the slide coating apparatus according to claim 1. 5. The method according to claim 4, wherein seven or more layers are simultaneously coated. 6. The method for producing a photosensitive material according to claim 4, wherein the coating is performed using a pseudoplastic liquid.