JPS63287575A - Coating equipment - Google Patents

Abstract

PURPOSE:To minimize uneven coating film thickness by giving the same sectional shape as a coating width control plate having an oblique angle to the side in contact with liquid in a slide hopper type injector to the sectional shape of an edge guide supporting both edges of film-like coating liquid. CONSTITUTION:At least one kind of film-like coating liquid by a slide hopper type injector 7 is struck against a supporting body 2 to be coated. Then, the same sectional shape as the coating width control plate 4 having an oblique angle theta to the side in contact with liquid in the slide hopper type injector 7 is given to the sectional shape of the edge guide 3 supporting both edges of the said film-like coating liquid and the control plate 4 and said edge guide 3 are integrally worked. As a result, the occurrence of uneven liquid film thickness by the coating width control plate 4 on the slide hopper type injector 7 can be minimized. Since the coating liquid flows smoothly on the joints between the coating width control plates 4 and the edge guides 3 on the slide edge part, the liquid can be delivered smoothly from a slide surface 8 to a curtain film 10.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a coating device.

Especially in the production of recording materials such as photographic light-sensitive materials such as photographic film and photographic paper, and magnetic recording materials such as magnetic recording tape.
The present invention relates to a device that applies a coating liquid such as a photographic emulsion or a magnetic agent to a continuously running long strip-shaped support (hereinafter referred to as a "web").

More specifically, the present invention relates to an apparatus for coating a thin film of IPi or two or more coating liquids by colliding with a support to be coated.

[Conventional technology]

A typical example of devices that apply a thin film of coating solution onto a support by colliding with the support is a curtain coating device.

Curtain coating equipment is a device that forms a free-falling curtain made of one or more types of coating liquid and causes it to collide 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, Japanese Patent Publications No. 49-24133 and No. 49-
Attempts have been made to apply a curtain coating apparatus to fields that require particularly high precision, such as the production of photographic light-sensitive materials, as disclosed in Japanese Patent No. 35447.

The slide hopper type liquid injector disclosed in Japanese Patent Publication Nos. 49-24133 and 49-35447 forms a free-falling curtain film, and in order to hold this, both ends of the thin film-like coating liquid are passed through the slide hopper. It has a different shape from the coating width regulating plate of the mold pourer, and the coating width regulating plate and the edge guide are independent.

Furthermore, Japanese Patent Application Laid-Open No. 51-57734 proposes an apparatus that uses a vertical coating liquid regulating plate and an edge guide integrated as a countermeasure against liquid bending in a curtain film due to the teapot effect.

[Problem that the invention seeks to solve]

However, in the former case, when the coating liquid moves from the slide surface to the curtain film, the coating liquid is disturbed where the coating width regulating plate and the edge guide come into contact. Due to this turbulence, a W/# film is formed near the edge guide, which has the disadvantage that a uniform coating film cannot be formed.

The latter method is certainly effective in preventing liquid bending of the curtain film due to the teapot effect, but since the coating liquid regulating plate and edge guide are arranged at right angles to the curtain film, the coating liquid is not regulated. When the paint spreads over the plate and the edge guide, a Vs film is formed inside the vicinity of the edge guide, which has the disadvantage that a uniform coating film cannot be formed.

The present invention eliminates the above-mentioned drawbacks of the conventional coating method, minimizes the uneven liquid film thickness caused by the coating width regulating plate in curtain coating, and also minimizes the uneven liquid film thickness caused by the coating width regulating plate and edge guide in the edge portion. By smoothing the flow of the coating solution, uneven liquid film thickness and acid can be eliminated, and by minimizing uneven liquid film thickness and acid at the edge guide, localized areas at both ends in the width direction of the curtain film can be prevented. The purpose of the present invention is to provide a coating device that can stably obtain a uniform liquid film thickness for thick coating and thin coating.

[Means for solving problems]

The present invention provides an edge guide that supports both ends of the thin film coating liquid in an apparatus for applying one or more thin film coating liquids by colliding with a support to be coated using a slide hopper type liquid injector. The cross-sectional shape is the same as that of the coating width regulating plate which has an inclination angle on the liquid contact side of the slide hopper type liquid injection device, and the coating width regulating plate and the edge guide are integrally processed. This is a coating device that does this.

In the present invention, the cross-sectional shape of the edge guide is the same as that of the coating width regulating plate, which has an inclined angle on the liquid contact side of the slide hopper type liquid injector, and the coating width regulating plate and the edge guide are integrally processed. , specifically the coating width regulating plate,
And the angle of inclination on the wetted side of the edge guide: 20°17
The angle should be in the range of 5 degrees, preferably in the range of 30 degrees to 65 degrees, and the vertical height of the wetted side of the coating width regulating plate and edge guide should be within 2 fl. It is preferable to have a range of 1 fi or less.

Materials for the integrated coating width regulating plate and edge guide used in the present invention include metal, resin, and glass.

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic perspective view of a curtain coating device showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view thereof. In FIG. 2, the coating liquid is sent to a slide hopper type liquid injector 7 by a pump P 1, passes through a manifold 5, passes through a slot 6, becomes a thin coating liquid, flows down a slide surface 8, and vertically flows down from a lip 9. A curtain film 10 is then applied onto the support 2.

[For production]

The present invention provides an apparatus for applying one or more types of coating liquid in the form of a thin film by colliding with a support to be coated, in which the cross-sectional shape of the edge guide supporting both ends of the coating liquid in the form of a thin film is of a slide hopper type. By having the same cross-sectional shape as the coating width regulating plate, which has an inclined angle on the wetted side of the liquid filling plate, and by integrating the coating width regulating plate and the edge guide, the slide surface width direction of the slide hopper type can be adjusted. It minimizes unevenness in the liquid film thickness, eliminates ripples and stagnation at the joint between the coating width regulating plate and the edge guide, and minimizes spread of coating at the edge guide, resulting in uniform coating. A curtain film can be formed.

〔Example〕

Examples will be given to further clarify the effects of the present invention. - Example 1 A comparative experiment between the coating apparatus according to the present invention and a conventional coating apparatus was conducted using coating liquids having the composition and physical properties shown in Table 1. Coating at a coating amount of 100 cc/po (lubricated state) onto a polyethylene terephthalate film 100 μm thick and 18 cm wide that is being transported at a speed of 100 m/min by the slide hopper type curtain coating device shown in Figures 1 and 2. did. The height of the curtain film here was 20 cm, and the height during coating was 15 cm.The integral material of the coating width regulating plate and edge guide was polyvinyl chloride (PVC), and the shape of the wetted surface was sloped. The angle was 45° and the vertical height was 0.5 cranes. In addition, after the coating film applied to the film was sufficiently gelled with cold air and then dried using a normal method, the thickness was measured using a thickness needle. There wasn't.

Table 1 Comparative Example-1 In the above example, an experiment was conducted by changing the coating width regulating plate and the edge guide as follows. (The coating liquid regulating plate and the edge guide are not integrated.) As a result, the coating width regulating plate and the edge guide rod were observed to be partially coated and thinly coated at the edges during this experiment. Observing the flow state of the coating liquid at the connection part, the coating liquid stagnates, and waves are generated downward from that part toward the curtain membrane.
It was observed that thin coating occurred near the edge guide.

Comparative Example 2 A coating experiment was conducted by changing the coating liquid regulating plate and edge guide in the example described above as follows.

(The coating liquid regulating plate and the edge guide are integrated.) As a result, extremely thick and thin coatings occurred at the edges.

〔Effect of the invention〕

The present invention provides an edge guide cross section that supports both ends of the thin film coating solution in a method of applying one or more coating solutions in the form of a thin film by colliding with a support to be coated using a slide hopper type liquid injector. The shape is the same as the coating width regulating plate with an inclined angle on the wetted side of a slide hopper type liquid injector.
A coating device having a cross-sectional shape and having the coating width regulating plate and the edge guide integrated into one piece prevents uneven liquid film thickness caused by the coating width regulating plate above the slide hopper. By smoothing the flow of the coating liquid at the connection between the coating width regulating plate and the edge guide at the edge of the slide surface, the liquid can be smoothly transferred from the slide surface to the curtain membrane. Furthermore, since the edge guide is inclined, it is possible to minimize the non-uniform liquid film thickness at the edge guide, which leads to an improvement in yield.

[Brief explanation of drawings]

FIG. 1 is a schematic oblique view of a curtain coating device showing an embodiment of the present invention, and FIG. 2 is a schematic sectional view thereof. l... Backup roller 2... Web 3... Edge guide 4... Coating width regulating plate 5... Manifold 6... Slot 7... Slide hopper liquid injector 8... Slide Surface 9...Main part 10...Curtain film P...Liquid pump for coating liquid θ...Coating width regulating plate and liquid contact surface inclination angle h of edge guide...Coating width regulating plate and , vertical height of the edge guide's wetted surface, and 3 other people) Figure 2

Claims (1)

[Claims] (1) In a device that uses a slide hopper type injector to apply one or more types of coating liquid in the form of a thin film by colliding with a support to be coated, an edge that supports both ends of the coating liquid in the form of a thin film is used. The guide has the same cross-sectional shape as the coating width regulating plate which has an inclined angle on the wetted side of the slide hopper type liquid injector, and the coating width regulating plate and the edge guide are integrally processed. coating equipment.