JPS59213730A - Conductive film and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a heat-sealable film with enough conductivity to protect the contents to be packaged from electrostatic troubles also having such transparency as to afford see-through ability for the contents, by subjecting a combination of thermoplastic synthetic pulp and conductive fiber to a paper machine followed by hot pressing. CONSTITUTION:A combination of (A) a thermoplastic synthetic pulp, (B) a conductive short fiber except genuine carbon fiber (pref. stainless steel fiber, Al- fiber, Al- or Ni-coated carbon fiber, with a length 1-40mm. and a diameter 1- 100mum), and, if required, (C) a chemical pulp are subjected to a paper machine followed by carrying out a hot pressing at temperatures higher than the melting point of said synthetic pulp, thus obtaining the objective film constituted by filmy transparent thermoplastic resin matrix with said conductive fiber dispersed in it in an electrically contacting state, having an opacity <=30% and a planar resistivity <=1X10<6>ohm.cm.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a conductive film suitable for use in packaging, etc., and more particularly, the present invention relates to a conductive film suitable for use in packaging, etc. The present invention relates to a conductive film that is transparent enough to be seen through and heat-sealable.

Electronic components such as semiconductor ICs and LSIs, printed circuit boards, magnetic tapes, etc. need to be protected from problems caused by dust attraction and static electricity during the packaging and shipping process. MOS type ICs are susceptible to dielectric breakdown (due to static electricity), so prevention of static electricity is essential. In order to protect products from these electrostatic disturbances, packaging them with a conductive film with low surface resistivity may be considered. Furthermore, since it is desirable for products such as the above-mentioned ICs to be able to see through and judge the packaged contents for transactions, when packaging with conductive film, it is required that the conductive film itself has a certain degree of transparency. be done.

However, conventionally known conductive papers include paper made by mixing conductive inorganic fine powder such as carbon pigment with cellulose pulp slurry (for example, Japanese Patent Application Laid-Open No. 1983-1999)
68194), papermaking pulp mixed with cut carbon fibers (for example, Japanese Patent Publication No. 45-32766), etc.; Since it is opaque, the conductive paper produced by papermaking is black or white and has no transparency. Furthermore, since the main component is cellulose pulp, it is completely impossible to heat seal it during packaging. In addition, synthetic resin films with metals such as nickel deposited on them have problems such as the deposited metals tend to flake off and are expensive, and those with antistatic agents mixed in make the films sticky and dusty. There are some drawbacks that are easy to come by.

The present invention has been made in view of the above points, and has sufficient conductivity to protect the contents to be packaged from static electricity damage, as well as transparency to the extent that the contents can be seen through. This was made to provide a heat-sealable conductive film.

The present applicant had previously filed an application for a transparent conductive paper containing carbon fiber as a conductive filler (Japanese Patent Application No. 57
As a result of repeated research on the following pages, it was discovered that an excellent conductive film that meets the above requirements can be obtained by using various conductive fibers as fillers, and the present invention has been achieved.

That is, the first invention of the present application is composed of a film-like transparent thermoplastic resin matrix in which short-fiber-like conductive fibers (excluding those consisting only of carbon fibers) are dispersed in electrical contact with each other, and the opacity is is 30 inches or less, and the in-plane specific resistance lXl
The present invention relates to a conductive film characterized by having a resistance of 0'Ω·m or less.

The opacity was measured using a Photovolt photoelectric reflectometer model 670.

Further, the in-plane specific resistance is generally expressed by the following formula.

R1 actual resistance value (Ω) T: Thickness of test piece (cm) W: Width of test piece (crn) Measurement of specific resistance in the plane direction is based on Japan Rubber Association method 5RIS2301
Compliant with.

This type of conductive film is produced by applying papermaking technology in which thermoplastic synthetic pulp is used as the raw material for the resin matrix, a specific amount of conductive fiber is blended, the mixture is made into paper, and then heated and pressed using calender rolls. This production was made possible for the first time by devising the following.

That is, the second invention of the present application is a method for manufacturing the conductive film according to the first invention of the present application, which comprises a thermoplastic synthetic pulp with a volume ratio of 99.5 to 70 and short fibrous conductive fibers (
Except for those consisting only of carbon fibers, paper is made by mixing 0.5 to 30 volume chi and is heated and pressurized at a temperature higher than the melting point of the thermoplastic synthetic pulp, and has an opacity of 30 chi or less. The present invention relates to a method for manufacturing a conductive film having a specific resistance in the in-plane direction of 1×1060·α or less.

The conductive fibers used in the present invention are mainly various types of metal fibers or fibers made by coating the surface of inorganic fibers such as carbon fibers and glass fibers with metal. It is also possible to use a material that can be made into a material having a small specific resistance value in the in-plane direction, such as a metal-deposited film cut into fibers, or an organic conductive fiber such as polyacetylene.

Metal fibers include steel fiber, stainless steel fiber, aluminum fiber, Xinqiu fiber, copper fiber,
Bronze fibers are available, but stainless steel fibers, aluminum fibers, sinchu fibers, etc., whose surfaces are not easily oxidized, are preferred because they are easy to handle. These metal fibers are generally produced in various diameters by a drawing method, etc., but for use in the present invention, fibers with a diameter of 1 to 100 μm, preferably 20 μm or less, and a fiber length of 1 to 40 μm, preferably 3-25M is good. If the diameter exceeds 100 μm, the thickness of the resulting film will be 100 μm or more, which is undesirable, and due to the weight of the fibers, the fibers tend to settle on one side of the film, which may result in uneven blending.

Still, the thicker the fiber, the easier it is to reduce the opacity of the film, but in order to disperse it evenly in papermaking, the diameter should be 20
It is desirable that it be less than μm.

If the fiber length is short (less than 1 tan), it becomes difficult to form a network of fibers within the film, which is undesirable.On the other hand, if the fiber length is 40 tan or more, there may be relatively wide areas where fibers are absent or large fiber agglomerates within the conductive film. This is not desirable because it makes it easier to create.

Even when using carbon fibers or glass fibers coated with metal, it is desirable that the coated metal be oxidizable, such as aluminum or nickel.

The carbon fiber serving as the core material may range from those fired at a relatively low temperature of about 1400° C. or less to graphitic fibers fired at a much higher temperature. The preferred form of carbon fiber is short fiber (chopped fiber) with a fiber length of 1 to 40 m and a thread diameter of 5 to 30 μm, and the surface of the fiber is coated with a metal such as aluminum or nickel by electroless plating or vacuum deposition. Depending on the method, conductive fibers coated with a thickness of about 90.5 to 3 μm can be used. When using glass fiber as the core material, the cutting length is 7 to 10 days,
A commercially available product can be used, in which chopped glass strands with a diameter of about 10 to 15 μm are coated with a metal such as sialuminium or nickel to a thickness of 3 to 5 μm by a method such as vacuum deposition or immersion in a metal bath. .

The thermoplastic resin serving as the matrix in the conductive film of the present invention may be polyolefin, polyacrylonitrile, polyester, polyamide, polyvinyl alcohol, etc.; it becomes transparent when melted by heating and returns to a solid polymer by cooling; hold. It is something.

The melting points of these materials are in the range of 100 to 260°C.

Particularly preferred among these are polyolefins that have a low melting point and are relatively inexpensive. Polyolefins include polyethylene, polypropylene, a copolymer of ethylene and propylene, a copolymer of ethylene or propylene and It includes a copolymer of propylene and vinyl acetate, acrylic acid, etc., a mixture thereof, or a polymer obtained by further chemical treatment of these. These polymers can also be used in combination with polyvinyl alcohol binders used in the paper industry. still,
When considering the heat sealability of the conductive film, it is preferable to use a conductive film having a melting point of 200° C. or lower, particularly 170° C. or lower.

The conductive film according to the present invention is mainly manufactured by applying paper manufacturing technology, and the matrix made of thermoplastic synthetic resin is formed using thermoplastic synthetic pulp as a raw material. The term "pulp" is generally used to refer to a collection of cellulose fibers extracted by mechanically or chemically processing plant materials, but here it refers to a fibrous material or an aggregate thereof, and the present invention Thermoplastic synthetic pulp includes all fibrous materials that can be made into paper, such as pulp made of thermoplastic synthetic resin, thermoplastic synthetic fibers, and thermoplastic synthetic fibrous binders.

In addition, in the conductive film according to the present invention, cellulose fibers are separated in the thermoplastic resin matrix of the conductive film by replacing a part of the thermoplastic synthetic pulp as a raw material with chemical pulp to increase the paper aggregate. It may be something that exists. The chemical pulp in the present invention includes not only sulfite pulp, kraft pulp, soda pulp, etc., but also semi-chemical pulp. Either pulp or unbleached pulp may be used. From the viewpoint of transparency, the chemical pulp preferable for use in the present invention is
Bleached sulfite pulp or bleached kraft pulp.

Although it is not necessarily desirable to use chemical pulp in combination with the resulting conductive film from the viewpoint of properties such as transparency and heat sealability, it is used in order to improve the formability when manufacturing the conductive film and from the viewpoint of price. It is something. However, the amount is limited to replacing 30 volumes or less of the thermoplastic synthetic pulp.

The conductive film according to the present invention is manufactured by the following method.

First, thermoplastic synthetic pulp and short fibrous conductive fibers are mixed. When mixing, the thermoplastic synthetic pulp is placed in hot water or the like in advance and stirred to disintegrate it, and the conductive fibers are also dispersed in water or the like and then mixed. The blending ratio of the thermoplastic synthetic pulp and the conductive fibers has an important meaning on the properties of the resulting conductive film, such as its in-plane resistivity and transparency. If the number of conductive fibers is too small, the contact between the fibers will be insufficient and a conductive film with low specific resistance in the plane direction cannot be obtained, and if the number of conductive fibers is too large, the opacity will become high. The optimal blending ratio of conductive fibers is
Although it may vary depending on the type of conductive fiber used and the thickness of the fiber, in order to obtain a conductive film with an in-plane specific resistance of I x 10'Ω・ff+ or less, a capacitance of at least 0.5 - or more,
Preferably, three or more volumes are mixed. In addition, in order to ensure the opacity of the conductive film to be 30 or less, the amount of conductive fibers should be 30 or less, preferably 10 or less, depending on the thickness.
Adjust below the capacity factor. The diameter of the conductive fiber is 5 to 10μm
In the case of 7 capacitance factor or less, in the case of 10 to 15 μm, 1
It is desirable that the capacitance be 2 or less, 20 or less for 15 to 20 μm, and 30 or less for 20 or more μm.

When blending chemical pulp as a raw material, the beaten pulp is mixed with the above raw material. The mixed raw materials are thoroughly stirred and sent to the paper making process as a homogeneous mixture.

In papermaking, the methods used in normal papermaking technology,
A paper machine consisting of a plow section, a pressing section, a drying section, etc. can be used. The dried base paper is heated and pressurized to make it transparent. Heat and pressure can be carried out by calendering or pot press processing, which makes the paper glossy and smooth the surface in the normal papermaking process, and the pressure conditions are 10 to 200 Kq/cm by normal calendering. 10-200 Kr/m when using linear pressure or hot press
be selected appropriately under the pressure of Further, under similar conditions, treatment using a calender for plastics can also be carried out.

Regarding the temperature conditions, it is different from normal calender treatment, etc., and it is essential to heat the pulp to a temperature higher than the melting point of the thermoplastic synthetic pulp. For example, when the thermoplastic resin is polyolefin, the temperature is about 130 to 200°C. This heating is
thermoplastic resin material formed from thermoplastic synthetic pulp)
It is necessary to make the IJ film transparent and to reduce the in-plane specific resistance value of the conductive film.

The conductive film according to the present invention has 0 points i in terms of transparency and flexibility.
- It is desirable that the thickness be 100 μm or less.

The conductive film produced as described above is made of a film-like transparent thermoplastic resin matrix (IJ), in which short conductive fibers are dispersed in an IJ box, and the conductive fibers have contact points with each other to generate electricity. In addition, the film has a portion in the thickness direction where there are no conductive fibers, that is, a portion where there is only a transparent resin matrix. Therefore, electrical conduction occurs through the many contacts of the conductive fibers, so
A transparent conductive film having a small in-plane specific resistance of 1×10 6 Ω·m or less and an opacity of 30 or less because light is transmitted through the transparent resin matrix portion can be obtained.

The present invention makes it possible to obtain a conductive film with conductivity and transparency, which did not exist in the past, because a small amount of conductive fibers is dispersed in a thermoplastic resin matrix without being cut. It is. This is because the conductive film according to the present invention is made by applying paper manufacturing technology, and conductive fibers are dispersed in a resin matrix using conventional plastic molding technology such as injection molding or extrusion. Nothing similar can be achieved with the composite materials that are made. The conductive fibers are cut into extremely fine fibers by the shearing force caused by the scree in the picks, plastic molding machines, etc., making it impossible to have a large number of contacts, and the contact resistance itself at the contacts increases due to wetting with the resin due to cross-wires. This is because a large amount of conductive fibers must be blended in order to ensure conductivity, and if a large amount of conductive fibers is blended, on the other hand, transparency cannot be obtained.

On the other hand, since the conductive film of the present invention is manufactured by applying paper-making technology, the conductive fibers are made into paper without being damaged for the most part, and even when they are then fixed under pressure and heat, they are made of thermoplastic synthetic pulp. The change in state due to the melting of the conductive fibers acts as a buffer against the calender pressure to protect the conductive fibers from breakage. It is gripped by plastic synthetic pulp and left to cool after treatment to form a conductive film. Therefore, the conductive film of the present invention has many contact points, which reduces the total resistance value, like a parallel resistance. This is considered to be the reason why a low in-plane specific resistance can be obtained despite the small amount of conductive fibers added.

In carrying out the present invention, a natural or synthetic polymer substance with a refractive index lower than that of cellulose or equivalent to that of cellulose and whose melting point is similar to that of thermoplastic synthetic pulp is used as a papermaking raw material to make it transparent. It is equally acceptable to mix it into paper stock as an agent.

Further, various binders, surfactants, paper strength enhancers, antifoaming agents, etc. may be added to the papermaking raw materials. Further, in order to promote transparency, it is possible to use known techniques such as dumping water into the base paper and treating it with a super calendar, or increasing the linear pressure to such an extent that the conductive fibers are not cut.

Depending on the type of thermoplastic synthetic pulp, a hot air heating machine, an infrared heating machine, etc. can also be used in combination. In addition, the papermaking process is preferably carried out at a drying temperature below the softening point of the thermoplastic synthetic pulp.

The conductive film obtained by the present invention is practically as transparent as or more transparent than glassine paper, and has antistatic properties and heat sealing properties, making it a novel and useful product that meets the needs of the industry. It is something.

In the conductive film according to the present invention, a desired specific resistance can be obtained depending on the blending ratio of the conductive fibers, and the in-plane specific resistance is mainly 10' to 10.

The one with a Ω diameter is suitable for use as a bag to prevent dust from adhering to electronic parts and the like and to prevent electrostatic interference, and the one with a 10° to 10-20 Ω diameter is suitable for applications requiring an electromagnetic wave shielding effect.

In addition, when metal fibers or metal-coated fibers are used as the conductive fibers, the conductive film is silvery white or the like, which is more commercially effective than a black film using carbon fibers.

Further, the conductive film of the present invention can be used by laminating it with other transparent materials or pasting with opaque materials, or can be used as an embossed product with some opaque parts remaining.

The method for manufacturing the conductive film according to the present invention has been described above using a paper manufacturing method, but a dry nonwoven fabric manufacturing method can also be adopted based on the same technical idea.

Example thermoplastic synthetic pulp was SWP UL'410 (manufactured by Mitsui Petrochemicals, polyethylene resin, melting point 123°C, specific gravity 0.94, average fiber length 0.9, whiteness 94% or more).
Using stainless steel fiber (manufactured by Nippon Gokin, average fiber length 3 m, diameter 8 μrn) as the conductive fiber,
By changing these mixing ratios, various sheets with a target basis weight of 5 oy/m2 were prepared as experimental samples.

SWP■UL410. ! The stainless steel fibers were each dispersed in water and then mixed. Drying of base paper is 8
This is carried out at a temperature of 0 to 100°C at a linear pressure of 60 Kq/cr.
Heated in a super calender at n% temperature of 130℃,
Pressure treatment was performed to produce conductive films with various mixing ratios.

Figure 1 shows the relationship between the in-plane specific resistance and the amount of stainless steel fiber (capacity ratio) for the obtained conductive film.
) is shown in FIG. 2.

From Figure 1, the conductive film containing stainless steel fibers with a capacity factor of 0.5 or more has a sufficiently low in-plane specific resistance value of 1 x 102Ω. The in-plane specific resistance value suddenly decreases from around - or above. Therefore, by adjusting the amount of stainless steel fibers in the range of 0.5 or more by volume, a conductive film having the desired in-plane specific resistance value can be obtained.

According to FIG. 2, the opacity increases as the amount of stainless steel fibers is increased, but if the amount is 12 parts by volume or less, a conductive film with an opacity of 30 parts or less can be obtained. In particular, when the volume is 8 or less, the opacity is 20 or less, and when the volume is 5 or less, the opacity is 15% or less, and a conductive film with excellent transparency can be obtained.

The most desirable blending amount in terms of both in-plane resistivity and transparency is a range of about 3 to 5 volumetric stainless steel fibers.

EXAMPLE Conductive films containing various amounts of fibers were produced in the same manner as in Experimental Example 1, except that carbon fibers whose surfaces were coated with nickel were used as the conductive fibers.

The carbon fiber used as the core material was a pitch-based carbon fiber manufactured by Gugen Kagaku Kogyo Co., Ltd. with an average fiber length of 6 m and a single fiber diameter of 12.5 μm, and a nickel coating layer with a thickness of about 1 μm was formed on its surface by chemical plating.

In addition, the same conductive fibers as above were used, and 20% by weight (12% by volume) of the thermoplastic synthetic pulp was replaced with chemical pulp, but in the same manner as in Experimental Example 1, conductive films with various fiber blending amounts were prepared. was manufactured. NBKP as chemical pulp
(softwood bleached kraft pulp) was used.

NBKP-free and NBKP obtained as above
FIG. 3 shows the relationship between the in-plane specific resistance of the conductive film and the amount of Ni-coated carbon fiber (capacity ratio) in each conductive film, and FIG. 4 shows the relationship with the opacity of the conductive film. In FIGS. 3 and 4, the black mark indicates the case without NBKP, and the difficult mark indicates the case with NBKP.

From FIG. 3, a conductive film with a specific resistance in the planar direction of IX10'Ω・α or less, which is sufficiently higher than l It is clear that a film with a smaller specific resistance value can be obtained. When the blending amount is around 2 to 3 volumes, it is possible to obtain a film whose in-plane resistivity value is suddenly smaller than υ, lXl0''Ω·α or less.

Also, regarding the opacity of the conductive film, from Figure 4, N
The conductive film without BKP shows almost the same tendency as in Experimental Example 1 when stainless steel fibers were used. Regarding conductive films containing NBKP, the opacity is relatively high, and as the amount of conductive fibers is increased, the opacity tends to increase, but even in this case, when the amount of conductive fibers is 8. If the capacitance is below, a conductive film with an opacity of 30% or less has been obtained.

Examples Conductive films with various blending amounts of fibers were produced in the same manner as in Experimental Example 1, except that commercially available aluminum-coated glass fibers (manufactured by Diamond Jamrock Co., Ltd., average fiber length 4, diameter 20 μm) were used as conductive films. .

Regarding the obtained conductive film, the relationship between the in-plane specific resistance and the opacity with respect to the blending amount (volume %) of aluminum-coated glass fibers is shown in FIGS. 5 and 6, respectively.

As is clear from Figure 5, the specific resistance in the plane direction is 1×101
This is because a conductive film that is sufficiently smaller than 1Ω/stripe was obtained.

Regarding the opacity of the conductive film, since the diameter of the conductive fibers used is relatively large at 20 μm, the rate of increase in opacity as the amount of the compound increases is small; however, to reduce the opacity to 30% or less, It is necessary to have a volume of 30 cm or less, and in order to ensure an opacity of 20 cm or less, it is desirable that the blending amount be 10 volumes or less.

Example 1 A certain amount of thermoplastic synthetic pulp swP UL410 (manufactured by Mitsui Petrochemicals, polyethylene resin, melting point 123°C) (hereinafter abbreviated as SWP) was poured into hot water at 50°C, and
The mixture was adjusted to a concentration of Also, stainless steel
Steel fiber (manufactured by Nippon Yakin, average fiber length 3m, diameter 8μ
m) (hereinafter abbreviated as SSF) is dispersed in water at room temperature to a concentration of 1 g, and Trimine DF is added as an antifoaming agent to this.
130 (adjusted by adding a small amount of Miyoshi oil and fat (manufactured by Kiki).

The mixing ratio of SWP/SSF is 60/40 in parts by weight.
(92.9/7.1% by volume), put into a mixing tank and stir for 10 minutes, then add PEO as a dispersant.
0.06% of ■-PF (manufactured by Tetsusei Kagaku ■) was added to the raw material, and a base paper was produced with a target basis weight of 50 r/m'.

The base paper was dried at 80 to 100°C. Linear pressure 6
A conductive film was produced by processing in a super calendar at 0 kg/cm and a temperature of 130°C. Table 1 shows the physical properties of the obtained conductive film.

Table 1: The conductive film consists of silver-colored stainless steel fibers dispersed in a transparent resin matrix, and has an overall silvery-white, semi-transparent appearance, with an opacity lower than that of ordinary glassine paper. Ah, when it was made into a bag, the contents could be seen through. The high air permeability is due to the effect of melting the synthetic resin pulp, and therefore the moisture permeability is also low, so even if the bag was heat-sealed, water 11 was added, and the bag was left for a long time, there was no tactile sensation of water seeping out. . Moreover, the heat sealing strength was also sufficient.

Example 2 Four types of conductive films were produced in the same manner as in Example 1, except that the SWP/SSF mixing ratio was changed to the four times shown in Table 2.

The physical properties of each conductive film were as shown in Table 2.

Table 2 Both conductive films had excellent transparency.

Example 3 As a conductive fiber, a fiber whose surface was coated with nickel with a thickness of about 1 μm by chemical plating was used as a carbon fiber (pitch-based carbon fiber manufactured by Gugen Kagaku Kogyo, average fiber length 6 yen, single fiber diameter 12.5 μm). (hereinafter abbreviated as N1-CF), three types of conductive films were manufactured in the same manner as in Example 1 except that SWP and Ni''cF were blended at each mixing ratio shown in Table 3.

The physical properties of each conductive film were as shown in Table 3.

Table 3 Example 4 A conductive film was manufactured by replacing 20% by weight (12% by volume) of SWP in Example 3 with a chemical valve. As a chemical valve, softwood bleached kraft pulp (hereinafter referred to as NB) is used.
(referred to as KP), and the freeness was 300 using a test beater.
A conductive film was produced in the same manner as in Example 3 except that the product was beaten to m1C8F (Canadian standard reactor water profile) and mixed with a mixed dispersion of SWP and N1-CF. Table 4 shows each mixing ratio and the properties of the obtained conductive film.

Table 4 Although the opacity was slightly higher than that of the conductive film of Example 3 in which NBKP was not mixed, it was sufficient to allow the contents to be seen through when used for packaging.

Example 5 Commercially available aluminum coated glass fiber (
Made by Diamond Jamrock, average fiber length 4+nm, glass core diameter approx. 13μm1 aluminum coating thickness approx. 3.5
(hereinafter referred to as A[-G
A conductive film was produced in the same manner as in Example 1, except that SWP and AA-'CF were blended at each mixing ratio shown in Table 5. The physical properties of each conductive film were as shown in Table 5.

Table 5 Example 6 ES-Ch instead of SWP as thermoplastic synthetic pulp
OP■ (composite fiber of polyethylene and polypropylene manufactured by Chisso ■, melting point 165-170℃, fiber length 5mm, fineness 3
72/8/20, (90,
2/'6.9/, and a conductive film was manufactured. The physical properties of the conductive film are shown in Table 6.

Compared to the conductive film of Example 1 in Table 6, the opacity was slightly lower and the in-plane specific resistance was at the same level.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between the in-plane specific resistance of a conductive film and the amount of stainless steel fibers. FIG. 2 is a graph showing the relationship between the opacity of the conductive film and the amount of stainless steel fiber added. FIG. 3 is a graph showing the relationship between the in-plane specific resistance of the conductive film and the amount of nickel-coated carbon fiber. FIG. 4 is a graph showing the relationship between the opacity of the conductive film and the amount of nickel-coated carbon fiber. FIG. 5 is a graph showing the relationship between the in-plane specific resistance of the conductive film and the amount of aluminum-coated glass fiber incorporated. FIG. 6 is a graph showing the relationship between the opacity of the conductive film and the amount of aluminum-coated glass fiber. Stainless Steel Thread (2) Fig. 2 Ten Ball Handle #1 I (in capacity) (capacity)

Claims (9)

[Claims] (1) Film-like transparent thermoplastic resin (IJ)
Short fiber-like conductive fibers (excluding those consisting only of carbon fibers) are dispersed in the glass in electrical contact with each other, the opacity is 30 inches or less, and the specific resistance in the plane direction is 1 x 10°Ω.・
A conductive film characterized by α or less. (2) Claim 1 whose thickness is 100 μm or less
Conductive film as described in section. (3) The conductive film according to claim 1 or 2, wherein the conductive fibers have a fiber length of 1 to 40 fibers. (4) The conductive film according to any one of claims 1 to 3, wherein the conductive fibers have a diameter of 1 to 100 μm. (5) Claims in which the conductive fibers are stainless steel fibers, aluminum fibers, Shinchiu fibers, carbon fibers whose surfaces are coated with aluminum or nickel, or glass fibers whose surfaces are coated with aluminum or nickel. The conductive film according to any one of items 1 to 4. (6) The conductive film according to any one of claims 1 to 5, wherein cellulose fibers are dispersed in a film-like transparent thermoplastic resin matrix. (7) A paper made by mixing thermoplastic synthetic pulp and short fibrous conductive fibers (excluding those consisting only of carbon fibers) and then heating and pressurizing the paper at a temperature higher than the melting point of the thermoplastic synthetic pulp. A conductive film according to any one of claims 1 to 5. (8) Paper is made by mixing thermoplastic synthetic pulp, short fibrous conductive fibers (excluding those consisting only of carbon fibers), and chemical pulp, and then heating and pressurizing the mixture at a temperature equal to or higher than the melting point of the thermoplastic synthetic pulp. The conductive film according to claim 6, which is a conductive film. (9) Thermoplastic synthetic pulp with a capacity of 99.5 to 70 and short fibrous conductive fibers (excluding those consisting only of carbon fibers ()0)
．． 5 to 30 capacity paper is mixed and paper-made, and subjected to heating and pressure treatment at a temperature higher than the melting point of the thermoplastic synthetic pulp.The opacity is 30% or less and the in-plane specific resistance is I x 1.
A method for producing a conductive film having a resistance of 0'Ω·m or less. The method for producing a conductive film according to claim 9, wherein less than 30 volumes of thermoplastic synthetic pulp is replaced with chemical pulp.