JPH0987829A - Production of metallic vapor deposited film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a vapor-deposition-free zone with sufficient precision even in the case of a narrow tape by using, as a masking tape, a para-aramid film having respectively specified modulus of elasticity of extension and heat shrinkage factor, in a method for performing metallic vapor deposition while forming a vapor-deposition-free zone of prescribed width in a longitudinal direction. SOLUTION: Metallic vapor deposition is carried out while masking the surface of a film with an endless masking tape and forming a margine zone (a vapor-deposition-free zone) of prescribed width, continuing in a longitudinal direction, in the prescribed position in the width direction of a vapor deposited film. In this method, a para-aramid film, in which the modulus of elasticity of extension at 20 deg.C and the heat shrinkage factor at 200 deg.C are regulated, respectively, to >=1000kg/mm<2> and <=0.2%, is used as a masking tape. By this method, the troubles resulting from the meandering motion, curling, heat shrinkage, stretching, etc., of a masking tape can be perfectly prevented even in the case of a narrow tape of <= about 5mm width, and the vapor deposited film with a margin zone can be produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a non-deposited portion (margin portion) having a predetermined width and continuously formed in the longitudinal direction of a metal vapor-deposited film used mainly for capacitors. is there.

[0002]

2. Description of the Related Art Metallized films have been widely used as base materials for wound capacitors or laminated capacitors. In order to prevent a short circuit on the metal vapor deposition film,
A continuous non-vapor deposition portion is provided along one side edge of the vapor deposition film in the longitudinal direction (running direction of winding). This non-deposited portion is called a margin. As a method for forming the margin, a tape method,
Oil method and laser method. The tape method is a method of forming a margin part by using a plurality of narrow endless tapes at the time of vapor deposition and vapor-depositing while masking a part of the film with the tapes. The oil method is a method of forming a margin by utilizing the fact that a vapor deposition film is not formed on an oil application portion by applying oil to a place corresponding to the margin portion and then performing vapor deposition. The laser method is a method in which a vapor deposition film is once formed on the entire width of the film, and then the vapor deposition metal in a portion corresponding to the margin portion is scattered by a laser beam to form the margin portion.

In any of the above methods, by slitting the widthwise center of the metal vapor deposition portion and the center of the margin portion, a plurality of vapor deposition films having a margin portion on one edge can be obtained.

Of the above methods, the laser method requires a large apparatus and high cost, and requires a separate process from vapor deposition.
It is less common than the other two methods. The oil method inherently has a problem that the boundary of the margin is blurred, and the tape method is the cheapest and reliable method for accurately forming a narrow margin.

The present invention relates to a tape system margin forming method, and a tape system will be described below. The tape method has been known for a long time,
Polyimide is used as the tape. Recent patent applications include JP-A-58-45376 and JP-A-6-
No. 3-166958 is known, and the tape used in these is also a polyimide tape. In addition, Japanese Patent Fairness 5-4
No. 5668 discloses a polyetherimide tape as a masking tape.

[0006]

By the way, it is advantageous in terms of the capacitance of the capacitor to make the area of the margin portion as small as possible. Is required. In order to reduce the width of the margin part, the width of the tape must be narrowed, but there is also the risk of insulation failure when the margin width changes due to tape elongation, curling, heat shrinkage, meandering, etc. Increase. Polyimide has been the most preferred and has been adopted in terms of tape elongation, curling, heat shrinkage, meandering, etc. However, when the tape has a narrow width of 5 mm or less, heat shrinkage and tape elongation (especially heat However, it has become difficult to form sufficiently accurate margins with polyimide tape. It is an object of the present invention to provide a tape having a narrow width of 5 mm or less, which hardly expands when heated and does not cause heat shrinkage.

[0007]

The present invention adopts the following configurations in order to solve the above problems. That is, the present invention
In a metal deposition method of depositing a marginal portion having a predetermined width continuous in the longitudinal direction at a predetermined position in the width direction of a vapor-deposited film by masking the film surface with an endless masking tape Tensile modulus at 1000 ℃ /
characterized by using a para-aramid film having a heat shrinkage ratio of 0.2% or less at 200 ° C. or more at mm ²
The method for producing a metal vapor deposition film ".

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a para-aramid film used for a masking tape is a polymerization of an aromatic diamine having an amino group at the para position and an aromatic dicarboxylic acid having a carboxylic acid at the para position by a condensation reaction. Film of wholly aromatic polyamide prepared. Further, as long as it has the same structure as the above, it may be polymerized through another polymerization route.

Examples of the aromatic diamine having an amino group at the para position include the monomers illustrated in FIG.
Examples of the aromatic dicarboxylic acid having a carboxylic acid in the para position include the monomers illustrated in FIG. Typical examples of the para-aramid film used in the present invention include the polymers illustrated in FIG.

[0010]

FIG.

[0011]

[Fig. 2]

[0012]

[Figure 3]

The para-aramid film used in the present invention must have a tensile elastic modulus at 20 ° C. of 1000 kg / mm ² or more and a thermal shrinkage at 200 ° C. of 0.2% or less. Examples of such para-aramid film include the above-mentioned polymers (exemplified in FIG. 3) and the like.

The thickness of the masking tape of the para-aramid film used in the present invention is 25 to 100 μm, and the width of the tape is 1 to 10 mm. In order to make the tape endless, it may be bonded with an adhesive, or a method of heat-sealing a substance coated on the surface of the aramid film may be used. Examples of the substance to be coated on the surface include Teflon and epoxy resin. In order to actually make a tape having a narrow width of a predetermined length, it is preferable to wind the film on a drum having a predetermined circumference, bond the edges, and then cut the film into narrow strips. Further, it may be spirally wound around the drum.

As the film deposited in the present invention, a plastic film such as polypropylene, polyester, or polycarbonate can be used. The metal to be vapor-deposited in the present invention may be any metal, but zinc and aluminum are typical ones.

[0016]

【Example】

Example 1 An epoxy resin was applied to the surface of a para-aramid film (Aramika manufactured by Asahi Kasei) having a thickness of 50 μm, a tensile elastic modulus of 1300 kg / mm ² at 20 ° C., and a heat shrinkage of 0.12% at 200 ° C., The tape was wound around a drum and the edges were heat-sealed to form an endless tape having a width of 1.0 mm. Using a vacuum continuous vapor deposition machine, the above tape was used as a masking tape for forming a margin, and aluminum was continuously vapor deposited on a polyester film having a thickness of 3 μm. The visual evaluation of the margin portion was good, there was no meandering, and the width of the margin portion was 1.0 mm.

<Example 2> The continuous vapor deposition was evaluated in the same manner as in Example 1 except that the aramid tape was changed to that shown in Table 1. The results are shown in Table 1.

<Comparative Examples 1 and 2> Continuous vapor deposition was evaluated in the same manner as in Example 1 except that a polyimide tape whose tensile elastic modulus and heat shrinkage had the values shown in Table 1 were used. . The results are shown in Table 1.

<Measurement Method of Heat Shrinkage> A tape having a length of 10 cm was immersed in a silicone oil bath at 200 ° C. for 2 hours to measure the dimensional change in the longitudinal direction.

<Evaluation of Margin> Aluminum is made to have a thickness of 500 angstroms by a vacuum continuous vapor deposition machine.
Evaporate at 000 m, sample randomly, visually find the margin width, and measure the width of the smallest margin width. (If the film is curled, twisted, stretched, etc., the width of the margin will be narrowed.)

<Evaluation of meandering during running> In the same manner as above, visually observing the meandering of the margin portion is x, and it is difficult to see with the naked eye, but if observing with a loupe, meandering is observed. △, those where no meandering was observed ○
And

[0022]

[Table 1]

[0023]

Industrial Applicability According to the present invention, a vapor deposition film with a margin can be produced which has no troubles due to meandering, curling, heat shrinkage, elongation and the like of the masking tape.

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[Procedure amendment]

[Submission date] October 4, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

[0007]

The present invention adopts the following configurations in order to solve the above problems. That is, the present invention
In a metal vapor deposition method in which a film surface is masked with an endless masking tape to form a margin portion having a predetermined width continuous in the longitudinal direction at a predetermined position in the width direction of the vapor deposition film, a masking tape is used as a masking tape. Tensile elastic modulus at ℃ 1000kg
/ Mm ² or more, and a para-aramid film having a heat shrinkage ratio at 200 ° C. of 0.2% or less is used, and a “metal vapor deposition film manufacturing method”.

Claims (1)

[Claims] 1. A metal vapor deposition method for vapor-depositing a film surface by masking an endless masking tape at a predetermined position in the width direction of a vapor-deposited film while forming a margin portion having a predetermined width continuous in the longitudinal direction,
As a masking tape, tensile elastic modulus at 20 ℃ 1
A method for producing a metal vapor-deposited film, which comprises using a para-aramid film having a heat shrinkage rate of not more than 000 kg / mm ^{2 and not} more than 0.2% at 200 ° C.