JPH01320149A - Compound film for packaging rigid disc - Google Patents

Abstract

PURPOSE:To insulate steam, oxygen, nitrogen and the like, and have an efficient clean degree by arranging an antielectrostatic plastic film on both surfaces, and disposing a metallic foil between both materials. CONSTITUTION:A compound film for packing a rigid disc may be of a type in which an antielectrostatic plastic film is arranged in both surfaces, and a metallic foil is disposed therebetween. As an antielectrostatic plastic film arranged on both surfaces, it is generally used with films wherein an antistatic substance, such as alkyl amine, glyceric fatty acid ester, tetralkylammonium salt and the like are added or applied to a plastic film such as polyester film, polyamide film, polyolefin film and the like. Furthermore, a metallic foil is employed as an intermediate layer. As a metallic foil, an aluminium foil is preferable, and the thickness thereof is generally in the region of 9-15mum. The lamination of the antistatic plastic film and the metallic foil can be performed through a conventional and usual laminating method employing an adhesive agent and anchor coat agent.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a composite film for packaging rigid disks used for storing and transporting rigid disks.

[Conventional technology]

Conventionally, single-layer plastic films have been widely used as rigid disk packaging films. However, since single-layer plastic films have problems in terms of gas barrier properties, it has been proposed to perform lamination processing to form composite films.

[Problem to be solved by the invention]

However, when laminating plastic films,
Dust in the air adheres to the surface due to static electricity generated by friction with rolls, etc., making it impossible to obtain a sufficient degree of lean.
If this is used for packaging rigid discs, the functionality of the rigid discs will be degraded.

An object of the present invention is to solve the problems of the prior art and provide a composite film for packaging rigid disks that blocks water vapor, oxygen, nitrogen, etc. and has a sufficiently lean degree.

[Means to solve the problem]

In view of the above problems, as a result of intensive research, the present inventor found that by using anti-static plastic films on both sides and laminating metal foil between them, it would not only block water vapor, but also prevent dust from adhering to the surface. The inventors have discovered that it is possible to obtain a composite film for rigid disk packaging that has a high degree of strength, and have arrived at the present invention.

That is, the composite film for rigid disk packaging of the present invention has antistatic plastic films on both sides,
It is characterized by a metal foil placed between the two.

In the composite film of the present invention, the antistatic plastic films disposed on both sides include plastic films such as polyester films, polyamide films, and polyolefin films with antistatic properties such as alkylamines, glycerin fatty acid esters, and tetraalkylammonium salts. Those with added or coated substances are generally used. Antistatic substances generally have a 0.
It is used in a proportion of about 0.02 to 0.04% by weight. The thickness of these antistatic plastic films is usually 12~
A suitable thickness is 50 μm.

Metal foil is used as the intermediate layer of the composite film of the present invention. As the metal foil, aluminum foil is preferable, and its thickness is generally about 9 to 15 μm.

In addition to the metal foil, if necessary, any film can be laminated for purposes such as reinforcement.

The antistatic plastic film and the metal foil can be laminated by a conventional lamination method using an adhesive, an anchor coating agent, or the like.

The overall thickness of the composite film of the present invention is 110 to 130 μm
is appropriate, and the surface resistance is less than 10” Ω (65℃, 2
5%R11), water vapor transmission rate Ig/m”24hrs,
latm, hereinafter, oxygen transmission rate is lcc/m'・24h
rs, latm, or less (22° C., dry) (water vapor permeability and oxygen permeability are both measured by the Mocon method).

After the laminated composite film is laminated into a bag shape, it is subjected to ultrasonic cleaning with ultrapure water and used for packaging rigid disks.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example A urethane adhesive was applied to a 12 μm thick antistatic polyester film containing 0.02% by weight of glycerin fatty acid ester, and a 9 μm thick aluminum foil was dry laminated thereon.

Next, a stretched nylon film with a thickness of 15 μm was dry laminated on the aluminum foil surface, and a titanium-based anchor coating agent was further applied to the stretched nylon surface to form a film with a thickness of 20 μm.
A 40-50 μm thick antistatic ethylene-vinyl acetate copolymer film (5% vinyl acetate content) with 0.04% by weight alkylamine added was laminated via a ~30 μm polyethylene layer.

The surface resistance on both sides of the resulting composite film was 1060 or less (65°C, 25% R11), and the water vapor permeability was 1.0.
g/m' ・24hrs, lat+n or less, oxygen permeability is 1.0 CC/m' ・24hrs, latm or less (22℃, dry), (water vapor permeability and oxygen permeability are both measured by the Mocon method) It was difficult for dust to adhere to it.

After curing this composite film for a sufficient period of time, the width is 480 mm.
A tube-like bag with a length of 500 mm and a seal width of IQ mm was made, and then ultrasonically cleaned with ultrapure water to obtain a composite film bag with a high degree of cleanliness. This composite film bag was highly clean with less dust adhesion, blocked water vapor, oxygen, nitrogen, etc., and was excellent as a packaging film for storing or transporting rigid disks.

〔Effect of the invention〕

According to the composite film for rigid disk packaging of the present invention, since both sides are made of antistatic plastic film, there is little dust adhesion, and water vapor, oxygen,
Since it can effectively block nitrogen and the like, it does not deteriorate the functions of rigid disks, and is extremely useful as a film for packaging rigid disks.

Applicant Sony Corporation
Shadai Nippon Printing Co., Ltd.

Claims (2)

[Claims] (1) Antistatic plastic film is placed on both sides,
A composite film for rigid disk packaging characterized by having a metal foil arranged between the two. (2) The composite film for rigid disk packaging according to item 1, wherein the metal foil is aluminum foil.