JPH0215591Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a coating device. In particular, in the production of photosensitive printing plates for photographic light-sensitive materials such as photographic film and photographic paper, recording materials such as magnetic recording materials such as magnetic recording tape, and pressure-sensitive copying materials, continuously running long strip-shaped supports (hereinafter referred to as (referred to as the "web").
The present invention relates to an apparatus for applying a coating liquid such as a photographic emulsion or a magnetic agent to a surface. More specifically, the present invention relates to an apparatus that applies a thin film of coating liquid by colliding it with a traveling belt-shaped support.

Among the methods in which a thin film-like coating liquid is applied by colliding with a traveling belt-like support, a typical method is the curtain coating method.

[Prior art]

The curtain coating method is a method in which a free-falling curtain made of one or more coating liquids is formed, and the curtain is collided with the object to be coated to form a coating film on the object. However, due to the demand for improved coating quality, high-precision coating is gradually required, and in recent years, it has been disclosed in Japanese Patent Publication Nos. 49-24133 and 49-35447. Attempts have also been made to apply curtain coating methods to fields that require particularly high precision, such as the production of photographic materials.

The method disclosed in Japanese Patent Publication Nos. 49-24133 and 49-35447 involves applying one or more types of coating liquid to two supporting members (hereinafter referred to as "Etsuji Guide"
That's what it means. ) to form a thin, free-falling curtain that is applied to a continuously running web. The reason why the coating liquid is supplied between the two edge guides is to regulate the coating width and to stabilize the curtain film.

Regarding this Edge Guide, please refer to the Special Publication No. 49-14130
Outflow of the coating liquid at both ends of the thin rod or thin line disclosed in Japanese Patent Publication No. 51-57734, or the flat plate disclosed in Japanese Patent Application Publication No. 55-73365. A method of supporting with liquid ejected in the same direction is known.

As described above, there has not been much research on guides for curtain coating methods, and conventional guide mechanisms are of a fixed type, and the edges of the coating film formed by the guides are located in the center of the coating film. The major drawback was that the coating was much thicker than that of the original.

[Purpose of invention]

An object of the present invention is to provide a curtain coating device that automatically changes the coating width in response to changes in the width of the web and does not cause the thickness of the edge to become thick.

Another object of the present invention is to provide a curtain coating device that is compact in terms of equipment.

[Structure and action of the idea]

The purpose of the present invention is to enable suction treatment of the edges of the coating layer in a device that applies at least one coating liquid in the form of a thin film so as to collide with a running belt-shaped support to form a coating layer. The distance between the suction nozzle and the supporting members at both ends of the thin film coating liquid is 2 mm or more.
This is achieved by a coating device characterized in that it is provided in an integral structure at a position of 30 mm, and the integral structure is movable according to the coating width by a drive mechanism.

Hereinafter, embodiments of the present invention will be described in more detail based on the accompanying drawings.

The attached drawings all show examples in which a thin film is formed using a slide type liquid supply device.

In Figures 1 and 2, a liquid tank (not shown)
A fixed amount of the coating liquid S is fed into the cavity 4 in the slide hopper 1 via the metering pump P. The coating liquid S flows out through the slot 3 whose width is narrower than the cavity 4, flows down the sliding inclined surface 6 of the slide hopper 1 as a flowing layer 8, and flows down the tip lip of the inclined plate (hereinafter referred to as (referred to as a "rip"). In the lip 7, a free falling curtain of the coating liquid S, that is, a thin coating liquid film 9 is formed. On the other hand, a belt-shaped support 11 is running from the original roll through a pass roller 2, and a thin film-like coating liquid 9 is running.
collides with the traveling strip-shaped support 11 and the coating film 1
form 0.

As shown in FIGS. 1 and 2, two spaced vertical edge guides 20, 20' extend from the adjacent lip 7 just above the coating path. These edge guides promote the formation of a free-falling vertical curtain 9 and define its width as it impinges on the surface of the web 11.

In the embodiment shown in FIGS. 1 and 2,
The support guide mechanism of the present invention includes a track 12, a running body 13,
13', and these traveling bodies can be moved in the width direction of the support body by a drive mechanism (not shown) composed of, for example, an electric motor, a speed reducer, and a feed screw. That is, the edge guide 2 is moved from the traveling bodies 13, 13' which can slide on the track 12 fixedly suspended from the frame (not shown) of the coating machine.
0 and 20' are attached so as to be movable in the width direction of the web 11. That is, when the web end detector detects a change in the width of the web 11, the electric motor rotates the feed screw in the forward and reverse directions via the reducer, so that the running bodies 13 and 13' slide in the width direction on the track 12. The edge guides 20, 20' move and the coating width follows.

There are many other drive mechanisms, such as those that use a hydraulic cylinder and a slide guide mechanism, and those that use a pneumatic cylinder and a slide guide mechanism, and the present invention is not limited to a certain drive mechanism. Furthermore, various structures can be applied to the support and guide mechanism.

On the other hand, the width of the downstream layer 8 on the inclined plate is
The excess liquid in the part wider than the width of the slide hopper is removed from the support 11 at the part away from the tip lip 7 of the slide hopper.
The liquid is received in a surplus liquid receiving container 14 attached to the lower part of the liquid.

Immediately after the coating film 10 is formed, the edges are thickly coated, but the edge guides 20 and 20' are provided integrally with the traveling bodies 13 and 13', respectively, to perform suction treatment on the edges of the coating layer. Thick coating areas are smoothed by suction nozzles 15, 15' which can be used.
The suction nozzles 15, 15' are brought into a reduced pressure state by the suction blower 17.

Edge guides 20, 20' and suction nozzle 15,
15' is preferably in the range of 2 mm to 30 mm.
If it is less than 2 mm, the curtain will be disturbed by the influence of the suction wind, resulting in uneven coating, and if it is more than 30 mm, the liquid will spread to the ears, causing the coating liquid to go around the back side and stain the roller.

As the suction nozzle for the edge of the coating layer, in addition to the suction nozzles 15 and 15' shown in FIGS. 1 and 2, the suction nozzle described in U.S. Pat.
The suction nozzle described in Publication No. 73579, the suction nozzle described in Utility Model Application No. 141123/1988 (see Japanese Utility Model Application No. 49949/1987) filed by the present applicant, etc. are also applicable.
FIGS. 3 and 4 are diagrams showing an example of a suction nozzle, in which a web 1 carrying coating films 20, 20' runs in a direction perpendicular to the paper surface, and the coating films 20, 20'
is removed by suction nozzles 40, 40'.
The suction nozzles 40, 40' have a double-tube structure with cleaning liquid jet ports 45, 45' and suction ports 46, 46' provided at the tips, respectively, and the jet ports 45, 45' are located at the axis of the double pipe. 47 and 47', respectively, and the suction ports 46 and 46' are provided at the central axis of the double pipe. 48 in Figures 4 and 5,
Reference numeral 48' denotes a cleaning liquid supply port, into which water, solvent, etc. are supplied through a supply pipe (not shown), and the cleaning liquid is sent to the spout ports 45, 45' through a spirally connected structure 49, 49', and is then applied. The membranes 20, 20' are each wet diluted. In FIG. 4, reference numerals 50 and 50' denote exhaust ports, through which the edges of the wet and diluted coating layer are removed together with a cleaning solution through an exhaust pipe (not shown). A vacuum pump or the like is usually connected to the exhaust pipe.

The web used in the present invention includes paper, plastic film, metal, resin coated paper, synthetic paper, and the like. The material of the plastic film includes, for example, polyolefins such as polyethylene and polypropylene, vinyl polymers such as polyvinyl acetate, polyvinyl chloride, and polystyrene;
Polyamides such as 6,6-nylon and 6-nylon, polyesters such as polyethylene terephthalate and polyethylene-2,6-naphthalate, polycarbonates, and cellulose acetates such as cellulose triacetate and cellulose diacetate are used. Further, the resin used for resin coated paper is typically polyolefin such as polyethylene, but is not necessarily limited thereto. Further, as the metal web, for example, there is an aluminum web.

Furthermore, the term "coating liquid" includes liquid compositions of various types depending on the application, for example, coating of light-sensitive emulsion layers, undercoat layers, protective layers, back layers, etc. in photographic light-sensitive materials. Liquid: Coating liquid for magnetic layer, undercoat layer, lubricating layer, protective layer, backing layer, etc., as in magnetic recording media; Coating liquid for adhesive layer, colored layer, rust prevention layer, etc. These coating solutions contain a water-soluble binder and an organic binder.

[Effect of idea]

According to the present invention, the coating width automatically changes in response to changes in the width of the web, and it is possible to perform curtain coating without smearing the thickness of the edges and without coating the back of the coating liquid.

Furthermore, by integrating the guide mechanism, the equipment can be made compact, and the following effects can also be obtained.

(1) The load on the coating machine drying zone is reduced.

(2) There is no need to cut and remove the edges, improving yield.

[Brief explanation of the drawing]

FIG. 1 is a side view showing one embodiment of the present invention, and FIG. 2 is a front view with the center portion in the width direction omitted. FIG. 3 is a partial sectional view schematically showing another example of the processing nozzle used in the present invention, and FIG. 4 is a plan view thereof. 11... Running belt-shaped support, 13, 13'
... Traveling body, 15, 15', 40, 40'... Suction nozzle, 20, 20'... Support member.

Claims (1)

[Scope of utility model registration request] In an apparatus for coating at least one coating liquid in the form of a thin film so as to collide with a traveling band-shaped support to form a coating layer, a suction nozzle capable of performing a suction process on the edge of the coating layer is connected to the thin film. 1. A coating device, characterized in that the coating device is provided in an integral structure at a distance of 2 mm to 30 mm from supporting members at both ends of the coating liquid, and the integral structure is movable according to the coating width by a drive mechanism.