JP2520612B2 - Conductive barrier film - Google Patents

Description

TECHNICAL FIELD The present invention relates to a conductive barrier film. More specifically, it has high conductivity on the outer surface, is transparent, has excellent properties such as excellent barrier properties against water vapor and oxygen gas, and does not generate corrosive gas. The present invention relates to a conductive barrier film suitable for packaging articles such as parts that are susceptible to electrostatic damage and are easily damaged by moisture or corrosive gas.

[Prior Art] Among electronic components, semiconductor products such as IC and LSI or intermediate products thereof have a weak point that their functions are destroyed even by the influence of slight static discharge or electrostatic field. This electrostatic discharge occurs inside and outside the packaging material of the package of electronic components. That is, the electronic component moves within the package, frictions with the inner surface of the packaging material to generate static electricity, and this static electricity flows into the conductive portion of the electronic device to destroy the electronic component.

Moreover, the packaging material is charged by the contact and friction of the packaging material with an external object, and the static electricity flows into the electronic component, so that the packaging material is destroyed. Furthermore, when the packaging body is placed in an electrostatic field and the electrostatic shielding property of the packaging material is low, the electronic components in the packaging material are exposed to the electrostatic field, and as a result, the electronic components are destroyed.

Further, the package of electronic parts is required to be able to see through the inside of the package by inspection of customs and the like. If the inside cannot be seen through, this will break the packaging material and inspect it.
If the packaging material is torn, the electronic component will be unprotected against static electricity and will be unusable in the subsequent handling and transportation processes.

It is also known that when a thin package electronic component such as a flat package IC is mounted on a substrate, solder cracking occurs in a high temperature atmosphere of 230 ° C like vapor face soldering, which causes package cracking. .

Recent research has revealed that this phenomenon occurs because the flat package IC absorbs moisture through the package, and this moisture is rapidly heated to a high temperature by soldering and evaporates and rapidly expands. From this,
It has been recognized that it is necessary to wrap the IC in a package and keep it in a certain dry state.

It is also known that there is an electronic component such as a magnetic disk device which is not only sensitive to static electricity but also easily causes rust due to moisture and oxygen.

Stores electronic parts such as ICs, which are susceptible to static electricity damage, and uses a conventional polyolefin film that has been incorporated with an antistatic agent as a packaging material that allows the inside to be seen through, as well as a film and an antistatic agent that are covered with a thin metal layer to the extent that they can be seen through. Laminated films with polyolefin films are known (for those coated with a thin metal layer, USP 4,154,344
No., USP 4,156,751).

[Problems to be Solved by the Invention] However, the former has a drawback that the antistatic performance is low, and particularly when the humidity is low, the antistatic performance is extremely deteriorated, and the steam barrier property is poor.

In addition, the latter is effective in preventing electrostatic damage, but has a difficulty in water vapor barrier property and oxygen barrier property.

There is also a film in which an aluminum foil is laminated to improve the barrier property, but not only the inside cannot be seen through, but also the antistatic performance is poor.

In this way, since there is no film that does not cause electrostatic damage and has excellent barrier properties against water vapor and oxygen, put a large amount of silica gel in a package that uses the above-mentioned film having antistatic properties as a packaging material. It has been proposed to keep the inside of the package dry under a certain humidity, but due to the lack of water vapor barrier properties, the hygroscopic performance of silica gel deteriorates, and electronic parts absorb moisture during transportation and storage. There was a problem such as being damaged or causing rust. In addition, it is proposed that after packaging in a film with antistatic performance, repackaging with a film laminated with aluminum foil, but since the contents are invisible, there is a problem of opening the bag and time for packaging. There was a problem such as being expensive.

[Means and Actions for Solving Problems] According to the present invention, a conductive layer, which is a coating film containing carbon black of 0.01 to 0.8 g / m ² and an average thickness of 0.01 to 5 μm, and a hard plastic are used. A film having a supporting layer, a barrier layer which is a transparent inorganic metal compound vapor-deposited layer or a barrier synthetic resin layer, and an antistatic sealant layer made of a polyolefin resin in which an antistatic agent is kneaded, wherein The layer is arranged as one outer surface layer, the antistatic sealant layer is arranged as the other outer surface layer, and the barrier layer is arranged on the opposite side of the conductive layer with the support layer sandwiched therebetween. A conductive barrier film is provided.

The support layer made of hard plastic refers to a layer formed of a hard synthetic resin having a melting point of 140 ° C. or higher. Examples of the support layer include nylon-6 (Ny-6) and nylon-
Polyamide resin such as 66 (Ny-66) and nylon-610 (Ny-610); not only excellent in heat resistance like aromatic polyester resin such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), but also strong It is preferable that the resin has a large value and a large barrier property. Further, it is preferable that these resins are biaxially oriented film layers because various physical properties such as strength are good.

Biaxially oriented polypropylene film (OPP) and biaxially oriented polystyrene film, biaxially oriented polyvinyl alcohol film, biaxially oriented ethylene-vinyl alcohol copolymer film, which are slightly inferior to the above resins in physical properties, also support the present invention. It can be used as a layer.

The thickness of the support layer is preferably selected in the range of 5 μm to 100 μm. If it is too thin, the strength and film of the entire film will be strong, and if it is too thick, it will be difficult to handle it as a packaging film. In addition, when a plurality of support layers are provided as described below [layer structure of (4), (5), (9), and (10) described below]
The total thickness of the support layer should be within the above range.

The conductive layer in the present invention is a carbon black coating layer formed on a base layer (the above-mentioned hard plastic layer often serves as a base layer and is a transparent plastic layer).

The surface of the conductive layer of the present invention has a thickness of 0.2 μm to 10 μm as a surface layer.
Forming a transparent plastic layer of μm is preferable because it protects the conductive layer.

When the above-mentioned surface layer is formed on the surface of the coating layer of carbon black, it is preferable to have a structure in which carbon black partially projects from the surface layer.

The conductive layer having such a structure can be formed as described below.

First, a conductive coating material containing carbon black is applied on a base material to form a film.

This conductive coating material contains carbon black as a conductive component and, if necessary, further contains a binder, a dispersant, a solvent or a dispersion medium. The carbon black is preferably selected from those for conductive fillers. Various brands are available, but a selection scale that does not necessarily uniquely determine particle size, dispersibility, degree of graphitization by firing, degree of structure development, etc. has not been found. It is good practice to test several kinds of conductive fillers and select a brand with as high transparency as possible for the same conductivity. Specific examples include Ketjen black, furnace black, acetylene black, channel black, thermal black, etc., but Ketjen black gives the most preferable results.

The binder is as good as possible the adhesion to the substrate,
It is good to choose one that will help disperse the carbon black as much as possible.

As the binder, for example, latexes such as EVA latex, acrylic latex, SB latex, PVA, fibrin derivatives, starch derivatives, acrylic resin, EVA resin, styrene resin, etc. are used after being dissolved in a solvent. Resins and the like are used.

The amount of binder is especially careful and should not be too high. That is, the proportion of carbon black in the dry coating should be relatively large.

This seems to conflict with the purpose of obtaining a transparent coating film, but when the carbon black concentration in the dry coating film is relatively low, the mechanical strength of the coating film increases, Contamination due to desorption of carbon black is reduced, but the balance between conductivity and transparency is deteriorated. That is, if the film thickness is increased in order to obtain conductivity, the transparency becomes extremely poor. The concentration of carbon black in the conductive layer coating varies depending on the type of carbon black used, dispersion method, film formation method, etc., so it is difficult to describe a certain concentration range, but usually about 8% by weight As described above, 100% by weight of carbon black may be used if the darker one is desirable and the film forming method is selected. That is, it is possible to form a coating film by aggregating carbon particles without using any binder.

A surfactant is optionally added as a dispersant. Latexes usually contain some amount of surfactant, and in particular it may not be necessary to add a dispersant.
Further, since the binder used in the form of being dissolved in a solvent may also act as a dispersant, whether or not to use the dispersant and the amount of the dispersant to be used may be determined by judging the necessity in each case.

It is desirable that the amount of carbon black applied as a conductive paint is as small as possible so that conductivity can be obtained, in order to improve the see-through performance. This amount varies depending on the type of carbon black and the state of dispersion, but the upper limit must be 0.8 g / m ² , and is preferably 0.1 g / m ² or less. 0.01g for the lower limit
Must be / m ² . If it is more than the above upper limit, the fluoroscopic performance is inferior, and if it is less than the lower limit, it is usually difficult to develop the conductive performance. Further, the thickness of the conductive layer, that is, the average thickness of the layer in which carbon black is formed into a substantially continuous layer, is 5 μm to 0.
It is necessary to be 01 μm, preferably 1 μm to 0.01 μm
m is good.

As a characteristic of the conductive layer, it is necessary to have a structure in which carbon black partially projects from the surface layer. Such a special structure can be made in various ways.

First, a conductive layer that has a low binder content and is mechanically weak is formed, and by coating the surface layer on this, the conductive layer is deformed by the coating liquid for coating the surface layer or the mechanical action of the coating device. To create a protrusion.

It is also possible to apply a conductive coating that is difficult to level to fine dots using a gravure coater or the like, and leave the transferred fine dots as protrusions.

Further, a method of including agglomerated particles of carbon black in the conductive paint can also be used.

The particles in which carbon black is aggregated can form a portion protruding from the conductive layer to the surface layer side.

The protrusions illustrated in Example 1 are due to the aggregated particles. Further, in addition to carbon, minute conductors, for example, minute particles of graphite or metal can be mixed to form the protrusions.

It is also possible to mix fine powder that easily adsorbs carbon to form fine particles on which carbon is adsorbed and to form the protrusion. The amount of protrusions is difficult to analyze and has not been quantified sufficiently, but it is sufficient if the amount of protrusions is included so that they can be easily found by observing with a microscope.

By taking such a special structure, the surface resistance of the surface layer can be remarkably reduced. Although details of the cause of this effect are unknown, it is imagined that the projecting portion of the conductive layer on the surface layer is likely to cause the concentration of electric charges. Therefore, diffusion of the charge between the surface layer and the conductive layer is mainly caused by the projecting portion of the conductive layer. It is also possible that it will occur through.

The conductive layer may be usually applied on the substrate to have a substantially uniform thickness, but if desired, the thickness can be intentionally increased or decreased. Providing a continuous line-like and slightly thick part such as a fine mesh or parallel lines is effective for obtaining a product that is easy to see through and has a low surface resistivity in addition to the design effect. In this case, it is preferable that the distance between the lines is small, and it should be 20 mm or less as much as possible. Also, the line width should be as thin as possible, preferably 2 mm or less. This is because if the line spacing is too large, the protection performance against electrostatic interference becomes insufficient, and if the line width is too large, it becomes conspicuous when seeing through.

When the concentration of carbon black in the non-volatile content of the conductive coating material is as high as 70% by weight or more, the adhesive strength with the base material often becomes insufficient. However, as the concentration of carbon black increases, good conductivity is exhibited even if the transparent layer of carbon black as the conductive layer is thin. At this time, the coating film of this conductive paint seems to be one in which the liquid easily permeates, and when the synthetic resin liquid is applied to form a surface layer directly on the conductive layer, the conductivity of the conductive layer of carbon black is reduced. Adhesion between the conductive layer and the base material can be achieved by allowing the synthetic resin liquid to penetrate to the base material with almost no decrease, and selecting the surface layer synthetic resin from those with good adhesion to the base material. It was found that the sex can be improved.

Before applying the conductive paint to the base material, in order to improve the wettability with the base material and to improve the adhesiveness with the base material, the base material is subjected to a pretreatment such as corona discharge treatment or, if desired, an undercoat. You can also do

The surface layer can be provided by directly overlaying a coating film of a conductive paint and applying a transparent synthetic resin paint. Since this surface layer forms the surface layer of the antistatic plastic film or sheet, a material satisfying various surface properties required for the packaging material, that is, hardness, gloss, slipperiness, blocking resistance, etc., is selected. Should be.

Since the surface layer serves as the surface layer of the antistatic plastic film, it is generally considered that a synthetic resin having a low electric resistance should be used, but this is not always necessary. That is, the volume resistivity of the resin itself is very high, even if a thermoplastic resin such as ordinary polyolefin is used, the surface layer directly coated on the conductive layer as described above has a very high surface resistivity. It was found that it can be lowered. This was an unexpected effect, but it seems to be understood to some extent by providing the conductive layer with a portion protruding from the surface layer.

Examples of the resin that can be used as the surface layer include polystyrene,
Fiber-based plastics such as polyvinyl chloride and nitrification cotton,
Thermoplastic resins and phenolic resins such as polyethylene, EVA, polyacrylic acid ester, polymethacrylic acid ester, polyvinylidene chloride, polyamide, polyester, etc.,
A thermosetting resin such as an epoxy resin can be applied and used in the form of an emulsion or a solution. Alternatively, a method of applying a polymerizable monomer to form a polymerized film may be used.

Acrylic resins such as polyacrylic acid ester and polymethacrylic acid ester are particularly preferable in terms of strength, adhesiveness, transparency and the like.

Various additives such as wax can be added to the surface layer for the purpose of improving slipperiness and abrasion resistance. Polyethylene waxes are particularly suitable because they improve wear resistance and rarely contaminate other materials. A suitable thickness of the surface layer is between 10 mμ and 0.2 μm. Surface layer thinner than 10mμ makes antistatic effect insufficient,
Surface layers thicker than 0.2 μm lead to insufficient mechanical strength of the coating.

Next, as an inorganic metal compound vapor deposition layer as a barrier layer for ensuring water vapor and oxygen barrier properties, for example, silicon, aluminum, nickel, titanium, selenium, magnesium, barium, indium, calcium, zirconium, thorium, thallium, tantalum, Examples thereof include transparent vapor-deposited layers mainly composed of zinc or the like, or oxides, halides or nitrides thereof, or mixtures thereof. Examples of the barrier synthetic resin layer include vinylidene chloride resin, polyvinyl alcohol resin, ethylene-vinyl Examples thereof include alcohol copolymer resins.

Water vapor transmission rate (JIS Z
0208,40 ℃ × 90% RH) 4.0g / m ² · 24hr or less,
Oxygen permeability (ASTM D 1434, 23 ℃) is 20cc / m ² · 24hr · atm
It is desirable that one of the following barrier properties is satisfied.

The thickness of the inorganic metal compound vapor deposition layer is usually selected from the range of about 100 to 5000Å, preferably about 300 to 800Å. Thickness 10
If it is less than 0 Å, the transparency is good, but the barrier property is poor, and even if it is thicker than 5000 Å, it is difficult to improve the barrier property.
The transparency becomes worse.

This inorganic metal compound vapor-deposited layer may be vapor-deposited directly on the support layer, or may be vapor-deposited via the anchor coat layer.
The formation method is not limited at all, and any ordinary method such as a vacuum vapor deposition method, a reactive vapor deposition method, a sputtering method, a reactive sputtering method, an ion plating method, or a reactive ion plating method is adopted. Examples of the anchor coating agent include those of alkyl titanate type, polyisocyanate type, polyalkyleneimine type and the like. Its thickness is usually about 0.1 to 2 μm. Further, instead of providing the anchor coat layer, corona discharge treatment or plasma etching treatment may be applied, and the anchor coat and corona discharge treatment or plasma etching treatment may be used in combination.

The thickness of the barrier synthetic resin layer is usually selected from the range of about 1 to 50 μm. If the thickness is less than 1 μm, the barrier property is insufficient, and if it is more than 50 μm, it is economically disadvantageous. As a lamination method, for example, in a vinylidene chloride resin, a method of applying a vinylidene chloride latex produced by an emulsion polymerization method to a surface opposite to a conductive layer side of a support layer and forming by drying, or a vinylidene chloride resin film is attached. Or any ordinary method such as a method in which a vinylidene chloride-based latex is applied to another plastic film and dried, and the support layer is attached to the support layer by a dry lamination method, a PE extrusion lamination method, or the like. To be done.

As a method for laminating a polyvinyl alcohol resin and an ethylene-vinyl alcohol copolymer resin, a biaxially stretched or unstretched film formed by coating the resin on the surface opposite to the conductive layer side of the support layer is dry laminated or PE extruded. Any ordinary method such as laminating by a rouge laminating method or the like is adopted.

As the antistatic sealant layer, a polyolefin resin kneaded with an antistatic agent is used. Examples of the polyolefin resin include low density polyethylene (LDP
E), high density polyethylene (HDPE), linear low density polyethylene (L-LDPE), low crystalline polypropylene and other polyolefins; ethylene-vinyl acetate copolymer (EV
A); One or more ethylene ionomers (IR) can be used. As the antistatic agent kneaded into the polyolefin resin, various anionic, cationic, and nonionic surfactants are used, and these are used alone or in combination. As the anionic surfactant,
For example, polyoxyethylene alkyl ether sulfates, alkyl phosphates and the like, cationic surfactants such as quaternary ammonium salts such as distearyldimethylammonium chloride, and nonionic surfactants such as polyethylene. Examples thereof include glycol resin acid esters and siloxane-based compounds.

The thickness of the antistatic sealant layer is 10 μm to 100 μm
Is preferred. If the thickness is less than 10 μm, the sealing strength when forming the bag will be insufficient. If it is 100 μm or more, it is difficult to seal the bag when it is made, which is economically disadvantageous.

In the conductive barrier film of the present invention,
The conductive layer and the antistatic sealant layer (abbreviated as sealant layer) are each arranged as an outer surface layer on one side of the film, and the barrier layer is arranged on the opposite side of the conductive layer with the support layer interposed therebetween. The barrier layer is arranged so that it does not contact the conductive layer.

Here, so that the barrier layer does not come into contact with the conductive layer, in other words, by arranging the barrier layer so as to be an inner layer of the laminated film, the barrier layer is not damaged even if the conductive layer is damaged from the outside. You can prevent it from being damaged. The conductive layer retains its conductivity even if it is scratched, but once the barrier layer is scratched, the barrier property deteriorates.
It is essential in the present invention to arrange the barrier layer so as not to contact the conductive layer.

Here, the basic layer structure of the present invention will be described with reference to FIGS. 1 and 2, and the most basic layer structure of the present invention is as follows.
As shown in FIG. 1, conductive layer 1 / support layer 3 / barrier layer
4 / The layer structure of the antistatic sealant layer 5. Further, as shown in FIG. 2, the layer structure of surface layer 2 / conductive layer 1 / supporting layer 3 / barrier layer 4 / antistatic sealant layer 5 allows the conductive layer 1 to be protected by the surface layer 2. preferable.

Next, examples of preferable layer constitutions of the conductive barrier film of the present invention will be given.

(1) CB / PET / SiO / PE (belt protection) (2) Surface layer / CB / PET / SiO / PE (belt protection) (3) Surface layer / CB / PET / SiO / PE / PE (belt protection) (4 ) Surface layer / CB / PET / PE / SiO / PET / PE (belt protection) (5) Surface layer / CB / PET / PE / SiO / PET / PE / PE (belt protection) (6) CB / PET / PVDC / PE (Obi) (7) Surface / CB / PET / PVDC / PE (obi) (8) Surface / CB / PET / PVDC / PE / PE (obi) (9) Surface / CB / PET / PE / PVDC / PET / PE (belt protection) (10) Surface layer / CB / PET / PE / PVDC / PET / PE / PE (belt protection) However, the symbols of the above layer configurations have the following meanings.

CB: Carbon black coating layer PET: Polyethylene terephthalate layer SiO: SiO vapor deposition layer PE: Polyethylene layer PE (belt protection): A layer of a resin composition prepared by blending polyethylene with an antistatic agent VMAl: Aluminum vapor deposition layer PVDC: Polychlorination Vinylidene resin layer The film having the layer structure (1) of the above layer structures is PET.
An SiO vapor-deposited layer is provided on one side, carbon black is applied on the other side, and then polyethylene containing an antistatic agent is extruded and laminated on the SiO vapor-deposited surface.

The film having the layer structure of (2) has a surface layer formed on the surface of the CB layer of the film of (1), and is intended to increase the durability of the conductive layer by protecting the surface of the CB layer. This film can be produced by adding an operation for forming a surface layer to the method for producing a film of (1).

In the film having the layer structure of (3) above, the polyethylene layer containing the antistatic agent in the antistatic sealant layer is made as thin as possible, and a polyethylene layer containing no antistatic agent is provided for that portion to reduce the cost. It is designed, and polyethylene and antistatic agent-blended polyethylene are extruded at the same time and laminated, or a film of antistatic agent-blended polyethylene is separately prepared, and this is extruded through the polyethylene layer of the surface layer / CB / PET / SiO. It can be manufactured in the same manner as in the case of the film of (2) except that it is laminated on the SiO surface of the laminate.

The film having the layer structure of (4) has two support layers, one support layer is subjected to carbon black coating treatment, and the other support layer is provided with an inorganic metal compound vapor deposition layer. . Then, the surface layers that were individually prepared
It can be produced by laminating / CB / PET and SiO / PET through extruded polyethylene and then extruding polyethylene containing an antistatic agent. Since the film of (4) is placed inside PET as a supporting layer, the SiO layer is PE.
The T layer strengthens and protects more strongly, and the water vapor barrier property of the SiO layer becomes more reliable.

The film of (5) above is obtained by replacing the PE (belt barrier) of the film of (4) with PE / PE (belt barrier).
This is intended to reduce the cost by thinning the PE (belt barrier) layer of the film (4).

Films (1) to (1) having the layer structure of (6) to (10)
The SiO vapor deposition layer of (5) is replaced with a polyvinylidene chloride resin layer. The manufacturing method and the features of each laminated film are as follows.
It is almost the same as that described for the film of the corresponding SiO vapor deposition layer.

EXAMPLES Next, the present invention will be described with reference to examples.

Example 1 10% by weight of Ketjenblack EC from Lion Akzo Co., Ltd., which is a commercially available carbon black as a conductive filler, and a nonionic surfactant 8 as a dispersant.
A dispersion consisting of wt% and the balance water was made. Separately, as a binder, a solution was prepared by dissolving partially saponified vinyl acetate in a mixed solvent of methanol and water at a mixing weight ratio of 90:10 by 9.2% by weight.

While stirring 40 parts by weight of the carbon black dispersion,
60 parts by weight of binder solution is added to contain 4% by weight of carbon black, 3.2% by weight of surfactant and 5.5% by weight of binder, and the solvent is mixed with methanol and water at a weight ratio of 56:44. A conductive paint that is a solvent was prepared. The nonvolatile content of this conductive paint is 12.7% by weight, and the nonvolatile content is 31%.
Weight percent is carbon black.

If a mixed solvent of methanol and water is used as the solvent,
Carbon black was agglomerated to some extent by increasing the drying speed and lowering the surface tension as compared with water, making it easier to apply it to the plastic surface and reducing the dispersing action of the nonionic surfactant to some extent. The particles can be made easier.

One side of a biaxially stretched polyester film with a thickness of 12 μm is subjected to corona discharge treatment, and this surface is coated with the above conductive paint in a dry amount.
0.2g / m ^{2 A} gravure coater is applied, dried, and overlaid on top of this, an acrylic resin whose main component is methyl methacrylate.
A top coat paint containing 14.7% by weight and 0.3% by weight of polyethylene wax as a solvent was applied in a dry amount of 1 g / m ² and dried to obtain a laminate A having a surface layer / CB / PET layer structure.

When the specific gravity of the solid material obtained by drying each paint is 1, the thickness of the conductive layer is about 0.2 μm and the thickness of the surface layer is about 1 μm. Carbon black is applied at a rate of 0.06 g / m ² .

When the surface side of the cross section of this film was observed with a micrograph, it was confirmed that carbon black was partially projected from the surface layer.

On the other hand, one side of a biaxially oriented polyester film having a thickness of 12 μm, which is different from the above biaxially oriented polyester film, was subjected to corona discharge treatment, and a polyurethane anchor coating agent (Toyo Morton Co., Ltd. AD-527 + AD-9L-1) was applied to this surface. ) Is applied by the gravure coating method and dried, and then SiO powder is added to 10 ^-4 Torr
A vacuum vapor-deposited film of 500Å was continuously vapor-deposited under a vacuum of 1 to obtain a laminate B. The carbon black non-coated surface of the laminate A,
Polyethyleneimine (BASF Corporation Polymine-P) was applied as a anchor coating agent on the vapor-deposited surface of the laminate B by a gravure coating method, dried, and extruded with a thickness of 20 μm from the extruder T die to obtain a laminate A. The laminate B was laminated via an anchor coating agent to obtain a layer structure C of surface layer / CB / PET / PE / SiO / PET. Then, after the corona discharge treatment on the PET surface, a polyurethane anchor coating agent (Toyo Morton Co., Ltd. AD
-527 + AD-9L-1) is applied and dried, polyethylene with a thickness of 30 μm is extruded, and 20 μm of polyethylene containing 0.7 wt% Chemistat 1100 manufactured by Sanyo Kasei Co., Ltd., which is a nonionic antistatic agent, is extruded and laminated. Then, a conductive barrier film having the following layer constitution D surface layer / CB / PET / PE / SiO / PET / PE / PE (belt protection) was obtained.

The surface resistance of the laminate D was 9 × 10 ⁵ Ω, the surface resistance of the heat seal layer was 8 × 10 ¹¹ Ω, and the light transmittance was 45%, so that the object could be easily seen through.

When this bag was heat-sealed to make a bag with the PE surface inside, a bag with good bag-making processability and easy handling was obtained. In addition, by the JIS L 1048 Gakushin friction tester,
A test film was attached to the friction element instead of the white cloth, and a friction test between the film and the film was performed to measure the number of frictions until the surface resistance lost its initial value and stood up. This film was 25,000 times. Since more than one bag of this type is often used at the same time, the abrasion resistance of the same film is practically important, but this film has been shown to have excellent abrasion resistance. .

Also, the water vapor transmission rate of this conductive barrier film is
When measured according to JIS Z 0208, it was less than 0.2 g / m ² · 24 hr.

Comparative Example 1 0.7% by weight of Chemistat 1100 manufactured by Sanyo Chemical Industry Co., Ltd., which is a nonionic antistatic agent, is contained on the CB non-coated surface of the laminate A having the layer structure of surface layer / CB / PET obtained in Example 1. Polyethylene was laminated to a thickness of 65 μm by an extrusion coating method to form an antistatic sealant layer.

The water vapor transmission rate of the obtained laminated film was 5.5 g / m ² · 2 hr as measured according to JIS Z 0208.

Example 2 A conductive paint was prepared by mixing the carbon black used in Example 1, the styrene-butadiene latex containing a nonvolatile content of 40% by weight and water. This coating contains 70% by weight of non-volatile matter, including 2% by weight of non-volatile matter, of carbon black. The paint contained some agglomerated particles of carbon black. One side of a polypropylene film having a thickness of 20 μm was subjected to corona discharge treatment, an acrylic resin liquid having a carboxyl group was undercoated on the one side, and 0.12 g / m ^{2 of the} conductive coating material was applied in a dry amount and dried. Carbon black is applied at a rate of 0.08 g / m ² .

On top of this, a 15% ethyl alcohol solution of nitrified cotton was applied in a dry amount of 1.6 g / m ² and dried to obtain a laminate A of surface layer / CB / OPP. If the specific gravity of nitrified cotton is 1.6, the thickness of the coating film is 1 μm. When a cross section of this film was observed with a microscope, it was found that carbon black partially protruded from the surface layer.

On the other hand, the vinylidene chloride resin surface of Daicel Chemical Industries, Ltd. Senesi KOP ^# 20 HB10, which is commercially available as a film having a vinylidene chloride resin layer provided on one side of a biaxially oriented polypropylene film, and the carbon black Polyethyleneimine as an anchor coating agent is applied to the application surface by a gravure coating method and dried, and polyethylene is extruded with a thickness of 20 μm from an extruder T-die and laminated to form a surface layer / C.
A layer structure B of B / OPP / PE / PVDC / OPP was obtained. Then, after corona discharge treatment on the OPP surface, a polyurethane-based anchor coating agent (Toyo Morton Co., Ltd. AD-527 + AD-9L-1) was applied by gravure coating method and dried, and then polyethylene was extruded from the extruder T die. It is extruded at 30 μm, and further, non-ionic antistatic agent Sanyo Kasei Co., Ltd. Chemistat 1100 1.
Polyethylene containing 5% by weight was extruded to a thickness of 20 μm to obtain a conductive barrier film having a layer structure C of surface layer / CB / OPP 20 μm / PE / PVDC / OPP / PE / PE (belt protection).

The surface resistance of this laminate C is 6 × 10 ⁵ Ω, the surface resistance of the heat seal layer is 9 × 10 ¹⁰ Ω, and the light transmittance is 54%.
The transparency was good. When this bag was heat-sealed with the PE side facing inward to form a bag, a bag with good bag-making processability and easy handling was obtained. The water vapor transmission rate of this conductive barrier film was 1.8 g / m ² · 24 hr.

Example 3 Using the conductive barrier film obtained in Examples 1 and 2, a flat package IC was hermetically sealed together with 50 g of silica gel, and allowed to stand in 30 ° C. × 80% for 6 months,
When soldered to a printed circuit board by vapor fail soldering at 230 ° C, the package was not cracked and was successfully manufactured.

Comparative Example 2 As an antistatic agent, Chemistat manufactured by Sanyo Chemical Industry Co., Ltd.
Polyethylene bag containing 0.7% by weight of 1100 was formed into a film by the inculation method, and flat package IC was hermetically sealed together with 50 g of silica gel and left in 30 ° C x 80% for 6 months, and then vapor face solder at 230 ° C. When soldered to the printed circuit board with the ring, package cracking occurred.

[Effects of the Invention] The conductive barrier film of the present invention has high conductivity,
It is transparent and has an excellent property that it has excellent water vapor barrier properties and does not generate corrosive gas.In particular, it is vulnerable to electrostatic damage like electronic parts such as IC and LSI, and is not damaged by moisture or corrosive gas. Suitable for easy packaging of goods.

[Brief description of drawings]

FIG. 1 is a sectional view showing the most basic layer structure of the conductive barrier film according to the present invention, and FIG. 2 is a sectional view showing another basic layer structure. 1 ... Conductive layer 2 ... Surface layer 3 ... Support layer 4 ... Barrier layer 5 ... Antistatic sealant layer

Claims (1)

(57) [Claims] 1. A conductive layer, which is a coating film containing at least 0.01 to 0.8 g / m ² of carbon black and having an average thickness of 0.01 to 5 μm, a support layer made of hard plastic, and a transparent vapor-deposited inorganic metal compound layer, or A film having a barrier layer which is a barrier synthetic resin layer, and an antistatic sealant layer made of a polyolefin resin in which an antistatic agent is kneaded, wherein the conductive layer is arranged as one outer surface layer,
A conductive barrier film, wherein the antistatic sealant layer is arranged as the other outer surface layer, and the barrier layer is arranged on the side opposite to the conductive layer with the support layer interposed therebetween.