JPS6046017B2 - packaging bag - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a packaging bag, and more particularly to a bag for packaging electronic components.

Electronic components that are sensitive to static electricity, such as semiconductors, are easily damaged by static electricity before they are attached to electronic circuits, and even after they are attached to electronic circuits, which poses a major problem. .

Therefore, in order to protect electronic components from static electricity,
Plastic films and metal foils mixed with conductive substances such as carbon and metal powder are used as packaging materials for electronic components.

However, since these are all opaque, it is impossible to confirm the existence and damage of the electronic components inside, or to identify the type.

On the other hand, there are plastic films mixed with antistatic agents, but these have considerably high electrical resistance per unit area and are completely inadequate for protecting electronic components. It is easily affected by moisture and lacks stability. The present invention eliminates the above drawbacks and provides a bag for packaging electronic components that is sufficient to protect electronic components from static electricity as well as to allow the electronic components contained within the package to be seen through. .

In other words, this invention provides a heat-sealable transparent plastic film with a thin metal film on the heat-sealing surface of the transparent plastic film having a light transmittance of 25% or more and an electrical resistance of 1σ per unit area.
An electronic component characterized by using a packaging film provided under the conditions of Ω or less and a film thickness of 208 to 250, and forming a package with the plastic film on the outside and the metal thin film on the inside. It is a packaging bag.

This will be explained below with reference to the drawings.

Both FIGS. 1 and 2 are partially enlarged sectional views showing an example of a packaging film used in a bag for packaging electronic components of the present invention, and FIG. Show, first
It is a partially cutaway perspective view when a package is formed using the packaging film shown in the figure.

A heat-sealable transparent plastic film can be obtained, for example, by providing a heat-sealable layer 2 on one side of a transparent plastic film 1, as shown in FIG. As the transparent plastic film 1, polyester film, acrylic film, vinyl chloride film, fluororesin film, styrene film, polypropylene film, polyethylene film, and any other film that can be used as a packaging material can be used.

The transparent plastic film 1 preferably has a thickness of 4p to 100μ.

If the transparent plastic film 1 is thinner than 4 μm, it is extremely thin and extremely weak, so it is useless as a packaging material. If the transparent plastic film 1 is thicker than 100 μm, it will be too stiff and have a strong repulsive force, making handling extremely inconvenient during heat sealing and after packaging is formed. The heat-sealable layer 2 can be provided on the transparent plastic film 1 by laminating a polyethylene or other heat-sealable film, extruding a resin such as polyethylene, laminating it, or coating it. Usable resins include, for example, polyethylene, soft vinyl chloride, modified polyester, EVAl, and various other heat-fusible resins. The transparent plastic film having heat-sealing properties also has a heat-sealable layer 2 when the plastic film 1 itself is heat-sealable, as illustrated in FIG. You can also do it.

In the configuration shown in FIG. 1, the heat-sealing layer 2 can also be provided only for the actual heat-sealing, rather than covering the entire surface. The metal thin film 3 can be provided on the heat-sealed layer 2 by a conventionally known thin film production method such as a vacuum evaporation method, a sputtering method, an ion blating method, or an electron beam evaporation method.

The metal thin film 3 contains Cr. ．． Al, Ni, . Fe. ．． In
．． ．． AglAu. ．． Cu. ．． Sn,,Zn,. Tj. ．．
All metals such as Ni-Cr, alloys, and other metals capable of forming thin films can be used.

The metal thin film 3 needs to satisfy the following conditions: a light transmittance of 25% or more, an electrical resistance per unit area of 1 Cf3Ω or less, and a film thickness of 20A to 250A.

These conditions of light transmittance, electrical resistance, and film thickness are essential to achieving the object of the present invention. That is, if the light transmittance is lower than 25%, it will be difficult to see through the electronic components inside the package.

Also, if the electrical resistance is higher than 1Cf3Ω, the conductivity is poor;
It is insufficient to protect electronic components from electrostatic charges. The film thickness indicates not only the relationship with light transmittance and electrical resistance, but also the relationship with the heat-sealable layer 2. If the film thickness is outside the range of 20 to 250, the light transmittance will be 25% or more and the electrical resistance per unit area will be 1 (1
The condition of y3Ω or less cannot be met.

If the film thickness is thinner than 20A, the electrical resistance of some metals tends to be generally higher than 1Cf3Ω, resulting in insufficient protection of electronic components. If the film thickness is thicker than 250A, the light transmittance will be lower than 25%, making it difficult to see through the electronic components inside. In this way, the light transmittance, electrical resistance per unit area, and film thickness of the metal thin film 3 are deeply related to each other, and the metal thin film 3 is formed to satisfy any of these three conditions. There is a need.

The thickness of the metal thin film 3 is also the same as that of the transparent plastic film 1.
It is of critical importance in forming the packaging as the outer layer.

If the thickness of the metal thin film 3 is 250A or less, it is extremely thin and does not particularly affect the heat sealing of the heat-sealable layer 2 inside it, and it is different from the case where the metal thin film 3 is not present. Similarly, heat sealing is possible.However, if the metal thin film 3 exceeds 250A, it is no longer possible to perform heat sealing sufficiently.In this invention, the metal thin film 3 is formed with the transparent plastic film 1 on the outside.
is used as the inner side to form a package, and electronic components are packaged inside this package.

4 in the figure is a heat sealing part.

In this invention, the electrical resistance per unit area of the metal thin film 3 is 1.
Since it has a conductivity of Cf3Ω or less, electronic components can be sufficiently protected from static electricity generated inside and outside the package.

In particular, since the metal thin film 3 is present on the surface of the inside of the package,
The effects of static electricity are completely eliminated. In this invention, a film containing an antistatic agent is used as the transparent plastic film 1, and a transparent plastic film 1 containing an antistatic agent is used.
A layer containing an antistatic agent may be appropriately formed on one or both sides of the plate.

The layer containing the antistatic agent can also be provided at other appropriate locations. In this invention, when the package is formed, the metal thin film 3 becomes the inside of the transparent plastic film 1, so the weather resistance is extremely good.

Incidentally, in this invention, it is naturally possible to color the material as appropriate.

Example A heat-sealable polyester film (MeIjnex type #850, manufactured by ICI) with a modified polyester layer on one side of a polyester film having a thickness of 25 μm was used as a carrier sheet, and a vacuum degree of 1×10−4 T0r was obtained by vacuum evaporation method.
Cr was evaporated at a deposition distance of about 2×250 under conditions of r, and the light transmittance was 75% and the resistance per unit area was 1σΩ.
A 50A (7) Cr vapor-deposited film with a film thickness of 50A (7) is formed on the modified polyester layer of the carrier sheet, and then a package is formed by heat sealing with the polyester film on the outside and the Cr vapor-deposited film on the inside. A bag for packaging parts was obtained.

Next, a comparison example with conventional products is shown.

Using the electronic component packaging bag of the present invention obtained in the Examples, as a comparative example, a conventionally commercially available heat-sealable non-static polyethylene packaging (pink plastic bag manufactured by Tokyo Denki Kagaku Kogyo Co., Ltd.) was used as Sample 1, A package made by laminating a polyester film and a polyethylene film with a thickness of 25 μm was used as Sample 2.

A liquid crystal plate was enclosed in each of the above packages.

Next, a static electricity generator (pressure R
OSTAT) was used to irradiate the liquid crystal panel with 4 and o ions to check for irregularities in the letters and numbers within the liquid crystal panel. We also compared the transparency of the packaging. The results are shown in the table below.
In addition, O...no disturbance at all.

×...Very disturbed.

As is clear from the results in the table, when the electronic component packaging bag of this invention is used, there is no disturbance in the characters and numbers on the liquid crystal display, and compared to conventional products, it is extremely effective in protecting against static electricity. It has the following effects.

[Brief explanation of the drawing]

Both FIGS. 1 and 2 are partially enlarged cross-sectional views showing an example of a packaging film used in the electronic component packaging bag of the present invention, and FIG. 3 is a partially enlarged sectional view showing an example of the packaging film of the present invention. 2 is a partially cutaway perspective view of a package formed using the packaging film shown in FIG. 1; FIG. 1...Transparent plastic film, 2...
...Heat-sealable layer, 3...Metal thin film, 4
...Heat, seal section.

Claims (1)

[Claims] 1. A thin metal film with a light transmittance of 25 on the heat sealing surface of a transparent plastic film having heat sealability.
% or more, electrical resistance per unit area of 10^8 Ω or less, and film thickness of 20 Å to 250 Å, and a package was formed with the plastic film on the outside and the metal thin film on the inside. A bag for packaging electronic parts, which is characterized by: 2. The bag for packaging electronic components according to claim 1, wherein the transparent plastic film having heat-sealability is provided with a layer containing an antistatic agent on one or both sides.