Hermetically sealed container for large-sized precision sheet (semi-) product

Abstract

A relatively light and generally resinous hermetically sealed container is provided for accommodating, supporting and transporting a precision sheet (semi-)product, such as a photomask, safely and in an airtight manner without exerting an inappropriate stress thereto, which precision sheet (semi-)product has such a large planar size that encounters an extreme difficulty in integral resin molding of a half of a container therefor. The container includes a main body and a lid member which are generally symmetrical with each other and respectively have sealing peripheries to be abutted to each other. Each of the main body and the lid member includes a plurality of resin-sheets which are disposed in a plane, abutted to each other at an intermediate joint boundary therebetween and joined with each other at the joint boundary. A reinforcing metal belt member is disposed from outside along the joint boundary and hermetically bolted to the resin sheets.

Description

FIELD OF THE INVENTION AND RELATED ART [0001] The present invention relates to a hermetically sealed container suitably used for transportation of a precision sheet (semi-)product, i.e., a precision sheet product or a semi-product thereof before completion of the product such as a (glass) substrate thereof, inclusive of a photomask (including a reticle) or a pelicle as a protective film for such a photomask, a semiconductor wafer-related product, various display products inclusive of a liquid crystal display (LCD),etc., particularly a large-sized precision sheet (semi-)product which is intended herein to mean one which has a large planar size including at least 750 mm for at least one side thereof and a container for which is composed of two halves each of which has such a planar size that integral resin molding thereof is extremely difficult. [0002] A precision sheet (semi-)product as mentioned above is generally mechanically fragile in many cases, and a precision part or member fo...

AI Technical Summary

Benefits of technology

[0003] Accordingly, a principal object of the present invention is to provide a generally resin-made, hermetically sealed container of a relatively light weight capable of safely accommodating and supporting therein a large-sized precision sheet (semi-)product, such as a photomask, which has such a large planar size that encounters an extreme difficulty in integral resin molding of a half of a container therefor, without exerting inappropriate stress to the (semi-)product.

Problems solved by technology

A precision sheet (semi-)product as mentioned above is generally mechanically fragile in many cases, and a precision part or member formed thereon is further fragile in many cases.

Especially, such a sheet (semi-)product is frequently exported overseas from Japan by airplane, and minute dirt is liable to be introduced into the container due to a pressure difference between the inner space (particularly, a cargo space) of the airplane and the atmospheric pressure.

Further, as the attachment of minute dirt should be avoided, the formation of a container main body with a foam resin (e.g., Japanese Patent Laid-Open Application (JP-A) 2001-31165) or the disposition of a foam resin cushioning material in a container as frequently exercised for general-purpose glass products since such a foam resin is liable to generate minute dirt due to abrasion.

Corresponding thereto, some new problems have occurred.

However, if the container is composed of a metal material according to a conventional manner, the weight of the container is increased to 40 kg or more and the total weight thereof together with the content product is increased to 50 kg or more, so that the transportation thereof by human power becomes extremely difficult also due to the increase in outer contour size thereof.

Further, even if the production of a resin-made container is intended for providing a smaller-weight container, and a container for a large-sized precision sheet (semi-)product having a large planar size of larger than 750 mm for at least one side thereof is intended to be composed of two halves, there has not been developed a resin molding technique which uses a mold allowing the molding of such a large-sized half until the present.

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