Production apparatus of multilayer coating film

Abstract

A method for forming multiple coating layers produces a coating construction that has flexibility corresponding to the number of layers of multiple coating layers, by which a multilayer coating film can be produced with small film thickness without adherence of dust to a film surface, a drying fault such as unevenness induced by drying-wind on the film surface, or a coating fault such as a level variation and a streak. The multilayer coating film has a coating surface state of high quality with coating thickness deviation of 3% or less. In the method, a belt-like substrate is continuously fed. A coating / drying step follows, with multiple steps performed in a single unit. A plurality of coating layers are formed by sequentially performing the coating / drying step by multiple units. Finally, the belt-like substrate with the multiple coatings is continuously wound.

Description

[0001] This application is a division of co-pending application Ser. No. 10 / 341,245, filed on Jan. 14, 2003, the entire contents of which are hereby incorporated by reference.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to a production apparatus of a multilayer coating film, and particularly to a production apparatus of a multilayer coating film which produces function films such as a wide view angle film and an antireflection film that are used for liquid crystal displays. [0004] 2. Description of the Related Art [0005] Recently, various kinds of function films such as a wide view angle film and an antireflection film are widely used for a liquid crystal display. This function film needs to have a small film thickness, no adherence of dust to a coating surface, no coating fault such as a level variation and a streak, and no drying fault such as unevenness on the surface induced by drying-wind, and it further needs to have a high ...

AI Technical Summary

Benefits of technology

[0009] The present invention is achieved in view of the above-described circumstances, and has its object to provide a production apparatus of a multilayer coating film preferable for producing various kinds of function films such as a wide view angle film, and an antireflection film, since it is capable of easily building a coating construction with flexibility according to the number of layers of the multiple coating layers, and is capable of producing a multilayer coating film with small film thickness, without adherence of dust to the film surface, a drying fault such as unevenness induced by drying-wind on the film surface, and a coating fault such as a level variation and a streak, and further with a high quality coating surface state with a small coating thickness deviation.

Problems solved by technology

Since the above-described high quality is demanded, the function film with the high quality coating surface cannot be efficiently produced with an ordinary coating device.

For example, with a coating device equipped with one coater and a dryer, a web has to be repeatedly passed through the coating device as many times as the number of layers to perform multilayer coating, thus causing the disadvantage that a large variation occurs to the quality, and production efficiency becomes extremely low.

Only in terms of quality, it is considered to perform multilayer coating with a spattering device, but the production speed is extremely low with 1 m / min, and the production cost is too high, thus making it difficult to be adopted.

However, the multilayer coating apparatus is limited to three layer coating at the maximum in terms of operability because a delivery device and a winder for the web should not be far from the coater.

This apparatus has the disadvantage that a burden of cleaning the coating devices, an operation of passing the web through the devices and the like is too large, and too much loss of time concerning the maintenance is required.

However, in the gravure printing apparatus, it is difficult to build a preferable and flexible coating construction corresponding to the number of layers of the multiple coating layers, and the gravure printing apparatus is insufficient as a multilayer coating film production apparatus for a function film which is demanded to have the above-described high quality in terms of coating, drying, dust prevention and handling.

Accordingly, the fact is that there is no production apparatus of the multilayer coating films, especially, no preferable production apparatus of the multilayer coating films which efficiently produces high quality function films such as wide view angle films and antireflection films used for liquid crystal displays.

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