JPH0826449B2 - Method for manufacturing metallized film for capacitors - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metallized film for capacitors by vacuum vapor deposition using an oil mask system in which a masking oil is applied on a vapor deposition substrate to form a film of a conductive metal by vapor deposition to form a non-evaporated portion. It relates to a manufacturing method.

[0002]

2. Description of the Related Art Conventionally, a metal film of Al, Zn, Cu, Au, Ag or the like or tin oxide is left on a vapor-deposited base material such as a plastic film or a glass sheet, leaving a non-vapor-deposited portion, that is, in a pattern. A vacuum vapor deposition method for forming a metal oxide conductor film such as indium oxide or a mixture thereof (ITO) has been widely used, and various vapor deposition products for decoration or electrical use have been manufactured thereby. Typical examples of vapor deposition products having such a patterned vapor deposition film are, for example, a capacitor film in which a metal vapor deposition film is formed with a margin portion (non-evaporation portion) left, and an electrode substrate in which a transparent electrode film such as ITO is formed. As.

To form the above-described patterned vapor-deposited film on a vapor-deposited substrate, a method of forming a margin portion simultaneously with vapor deposition using a tape or an oil coating film as a masking material, or once forming a uniform film on the substrate is used. There is known a method of forming a margin portion by selectively removing the conductor film by a dry or wet etching method after forming such a conductor film.

However, among the various methods described above,
Generally, in the tape mask method in which an endless tape is used as a masking material, (I) the tape is repeatedly exposed to metal vapor, so that even if a heat-resistant tape is used, a dimensional change occurs during the vapor deposition work, and the tape guide roll is used. The margin part is apt to be disturbed in the width direction because it is misaligned. (II) The metal deposited by vapor deposition on the tape is peeled off and scattered in the form of particles to be wound up as a foreign substance in the metallized film being manufactured to make a defective product (III). Therefore, even an endless tape cannot be used for a long time, the length of the film that can be vapor-deposited is limited, and the tape must be replaced after each operation.
There are drawbacks such as.

Further, the etching method requires a complicated etching process and has a drawback that the manufacturing cost increases.

On the other hand, the oil mask method is a simple method in which the masking oil is applied to the position corresponding to the margin of the vapor deposition base material immediately before the vapor deposition step by jetting vapor from a nozzle or transfer from a roll. Since the margin portion is formed, it is expected that the tape mask system or the etching system is essentially improved. As a masking oil, conventionally used is an electrically insulating silicone oil (vacuum, Vol. 7, No. 12, 392).
Page), liquid paraffin, etc. are used.

However, in the conventional oil mask method, although depending on the vapor deposition material, a small amount of the conductor is attached to the place where the oil is attached, and it is difficult to form a clear margin portion. Because the boundary of is easily blurred,
For example, when a metallized film for a capacitor obtained by vapor deposition of Al is rolled up to form a precision small capacitor that has recently been highly demanded, the interlayer insulation resistance is lowered due to the incompleteness of the margin portion. Electrical characteristics cannot be obtained.

In order to solve these problems, a method of using an oil having an average molecular weight of 230 to 680 and a vapor pressure at 200 ° C. of 0.1 to 20 Torr, alone or in a mixture (Japanese Patent Publication No. 55-47113), a method of cooling the film and the adhered oil with a cooling roll after adhering the oil to suppress evaporation of the oil within a limit so that the oil remains on the film even after metal deposition (Japanese Patent Laid-Open Publication No. Sho 61 (1999)). No. 58-151011) has been proposed. However, it cannot be said that these methods are sufficient, for example, most of the commercially available Al-metallized metal films for capacitors are produced by the tape mask method despite the above-mentioned process problems. there were.

[0009]

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a vacuum vapor deposition method capable of forming a clear margin portion free from deposits of vapor deposits, particularly conductor vapor deposits, particularly metallized films for capacitors. It is to provide a manufacturing method of. Another object of the present invention is to provide a method for producing a metallized film for a capacitor by vacuum vapor deposition, which can provide a vapor deposition product which has no disorder in the margin portion and is free from defects due to entrained foreign matters. Still another object is to provide a method for producing a metallized film for a capacitor by vacuum evaporation of an oil mask system, which has high productivity and enables vapor deposition of a long film.

[0010]

MEANS FOR SOLVING THE PROBLEMS Gold for capacitors of the present invention
In order to achieve the above-mentioned object
It has been developed by
From the plastic film to form the non-metalized part
Applying masking oil in a pattern for cooling metal
Conductor metal is vapor-deposited along the roll surface, then vapor-deposited
Take the film from another position and roll it up on the product roll.
It is a method for continuously producing metallized films for capacitors.
Therefore, all of the above steps are performed in a vacuum vapor deposition machine, and
Formula (I)-(III) Formula (I)-(-C)₃F₆O-)_n-Formula (II)-(-C₃F₆O-)_n-(-C F₂O
−)_m-Formula (III)-(-C₂F_FourO-)_n-(-C F₂O
−)_m-(Where n and m are all perfluoroalkyl polyethers
A flat body that gives an average molecular weight of 1,000 to 15,000
(Representing the number of uniform repeating units)
Each of them, or a mixture of two or more of them.
The compound of perfluoroalkyl polyether is
Direct contact application by transfer or printing to stick film
It is characterized by doing. Perfluoroalkyl
As the polyether, the average molecular weight range is 1500 to
Those of 10,000 are particularly preferably used.

[0011]

In the present invention, the use of perfluoroalkylpolyether as a masking oil is not necessarily the reason for the predetermined effect, in particular, the deposition of deposits and the formation of a sharp margin at the edge during vapor deposition. Although not clear, the following can be considered.

Generally, in the oil mask type vacuum vapor deposition method, the reason why the coating oil exerts a predetermined masking effect is as follows: 1) vapor deposition of vapor of oil molecules vaporized or re-evaporated by the heat of vacuum or vapor of vapor of vapor. Effect, 2) physical shielding effect of the film itself, 3) effect of inhibiting formation of vapor deposition nuclei by oil, and the effect of 1) above was considered to be particularly effective (Japanese Patent Publication No. 55-47113). etc). However, the perfluoroalkyl polyether used in the present invention has a vapor pressure of about 10 ⁻¹ to 10 ⁻⁴ Torr at 200 ° C. even in the case where the preferable average molecular weight range is 1500 to 10000, and the conventional 1) above. It cannot be explained only by the way of thinking that is the main factor. On the other hand, the perfluoroalkyl polyether has a considerably high average molecular weight as compared with the conventional masking oil, as described above, which is 1,000 to 15,000.
It has an extremely small surface tension of about 20 dyne / cm or less and is excellent in releasability. Therefore, even if the perfluoroalkyl polyether evaporates to some extent under the vapor deposition conditions, and even when it remains as an oil film, its large molecules exert a masking effect on the deposition of the deposit particles, and The excellent chemical inertness and excellent releasability also contribute to prevention of formation of vapor deposition nuclei. Further, since the surface tension is extremely small, even if the amount of residual oil decreases due to evaporation or collision of deposit particles, reduction of the coating shape due to aggregation is prevented. Due to such factors, perfluoroalkyl polyether is considered to have an excellent effect of preventing deposition of deposits and an effect of forming a sharp margin portion at the edge.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a metallized film for capacitors according to an embodiment of the present invention will be specifically described below with reference to the drawings. FIG. 1 is an internal front view of an apparatus for semi-continuous production of a metallized film for capacitors by vacuum deposition of an oil mask system, and FIG. 2 is a partial plan view of the metallized film for capacitors obtained by the above method.

Referring to FIG. 1, in the vacuum chamber A, P
A raw film 2 unwound from a raw film roll 1 made of ET (polyethylene terephthalate) or the like is wound around a winding roll 4 via a cooling can 3. During this time, the film 2 is provided with an Al film disposed below the cooling can 3.
Vapor deposition is performed from the metal evaporation source 5 such as the above, but prior to that, perfluoroalkyl polyether is applied in stripes from the oil supply device 6 (transfer roll in this example) to form the non-vapor deposition portion. Film 7 to be rolled up after vapor deposition
As shown in the plan view of FIG. 2, a thin tape having a vapor deposition portion 8 and a margin portion 9 is generally slit along the center of each portion, and then wound and laminated to form a film capacitor. It

Perfluoroalkylposes used in the present invention
The polyether is preferably F- or CF at both ends.
₃-, CF₃O- or C₂F_FiveStabilized by − and repeated
The units are represented by the following formulas (I) to (III) formula (I)-(-C₃F₆O-)_n-Formula (II)-(-C₃F₆O-)_n-(-C F₂O
−)_m-Formula (III)-(-C₂F_FourO-)_n-(-C F₂O
−)_m-(Where n and m are all perfluoroalkyl polyethers
A flat body that gives an average molecular weight of 1,000 to 15,000
Having the structure shown below)
Each alone or as a mixture of two or more of them
Used. Note that n: m in the formulas (II) and (III)
Is the former, for example, about 30-40: 1
It is usually larger. Repeating unit-(-C₃F₆
O-)_n-Is a linear structure (formula (A) below) and branched
It may have any of the structures (formula (B) below).

[0016]

Embedded image

Examples of commercially available products are Demnam (trade name, manufactured by Daikin Industries, Ltd., linear structure of formula (I)), Krytox (trade name, manufactured by DuPont, branched structure of formula (I)), and Fomblin, trade name. (Manufactured by Montedison, branched structure of formula (II) and formula (III)).

As mentioned above, perfluoroalkyl polyethers having an average molecular weight of 1,000 to 15,000 are used, and those having an average molecular weight in the range of 1,500 to 10,000 are preferably used. Those having a molecular weight of less than 1000 have a high vapor pressure and a large evaporation loss during vacuum deposition. Further, the perfluoroalkyl polyether needs to have a viscosity suitable for coating, and if it exceeds 15,000, heating to a high temperature is required for coating, which causes deformation of the film at the time of coating on the film substrate. Not preferable.

In the above, a representative embodiment of the method for producing the metallized film for capacitors of the present invention has been described. However, it will be readily understood that various modifications are possible within the scope of the invention. For example, as the vapor deposition base material, other than PET described above, a plastic film such as polyimide, polycarbonate, polyacetate, polypropylene, or polyphenylene sulfide can be used. As the evaporation material, in addition to Al, Zn, C
Conductor metals such as u, Ni, Ag and Au are preferably used. In addition to the transfer roll described above, various printing means may be used as the oil supply device within a range permitted by device restrictions. Compared with the oil spray coating method, this direct contact coating method by transfer or printing forms not only a vertical margin portion parallel to the transport direction of the film 2 but also a horizontal margin pattern or the like. This is especially effective in the case. In order to uniformly apply an appropriate amount of oil to the film 2, an offset roll that is in contact with the transfer (or pattern printing) roll is provided prior to the transfer (or pattern printing) roll that directly contacts the film. It is preferred to first deposit the oil on the roll. The oil may be attached to the offset roll by coating, dipping, evaporation or spraying.

Further, as the vapor deposition method, in addition to vacuum vapor deposition in a narrow sense, various kinds of sputtering are possible, and accordingly, the vacuum degree can be selected in a wide range, for example, 10 ^-1 to 10 ^-6 Torr. Further, it goes without saying that vapor deposition on the film substrate is not limited to one side and may be performed on both sides.

The performance of the perfluoroalkyl polyether oil used in the present invention as a masking oil will be described below with reference to Reference Examples, Examples and Comparative Examples.

Reference Example 1 An oil mask type semi-continuous type as shown in FIG. 1 is used except that a hollow pipe-shaped spray coating device having a slit-shaped opening is used instead of the transfer roll as the oil supply device 6. Using a vapor deposition machine, the type of oil was changed and vapor deposition was performed. As the base film 2, a polyethylene terephthalate film (thickness 2 μ, width 500 mm, length 200
00m) and the film winding speed is 24 on one side.
Al was vapor-deposited at 0 m / min. The degree of vacuum of the oil supply device installation portion in the vapor deposition machine A was about 10 ^-2 Torr, and the degree of vacuum in the vicinity of Al vapor deposition was 1 to 3 x 10 ^-4 Torr.
The oil was sprayed and adhered to the film surface as vapor with a width of 1 mm at intervals of 8 mm. The surface resistance of the Al vapor deposition part is 1.
It was set to 7Ω / □ (film thickness of about 400Å).

Regarding metallized films for capacitors obtained by using different oils, the amount of adhered metal in the margin portion in the rolled state and the blurring of the boundary between the vaporized portion of the metallized film and the margin portion are visually observed. The observed results are shown in Table 1 below.

[0024]

[Table 1]

Further, when the margin was wiped with a gauze impregnated with methanol and subjected to luminescence analysis, Al was detected in the ones using liquid paraffin and dimethyl silicone, but one using perfluoroalkyl polyether. Was not detected.

As can be seen from Table 1 above, the effect of masking by the oil mask system varies greatly depending on the type of oil, and the specificity of perfluoroalkyl polyether is extremely clear.

Example As the oil supply device 6 of FIG. 1, referring to FIG. 3, the transfer roll 10 in contact with the film 2, the offset roll 11 in contact with the transfer roll, and the reference example 1 were used.
A hollow pipe-shaped spray coating device 12 having a slit-shaped opening was used. That is, in the spray coating device 12, perfluoroalkyl polyether (average molecular weight 150
0) was heated, ejected as vapor from a slit to be attached to the offset roll 11 and transferred to the transfer roll 10, whereby the film 2 was coated with perfluoroalkyl polyether on the outer side of the pattern of the transfer roll. A metallized film for capacitors was manufactured using various oils in the same manner as in Reference Example 1 except that the transfer roller was used as the oil supply system to the film.

The obtained results are almost the same as the results shown in Table 1 above according to Reference Example 1 in which the oil is spray-coated on the film 2, and the specificity of the perfluoroalkyl polyether as a masking oil is very clearly shown. It was

Reference Example 2 Next, in order to see the masking effect of Al vapor deposition on various films of perfluoroalkyl polyether, experiments were conducted using a bell jar type vapor deposition tester. Perfluoroalkyl polyether (average molecular weight 2500) was impregnated into a cotton swab and coated on various films in a linear shape with a width of about 5 mm, and Al was vapor-deposited on the oil-coated surface of the film. For comparison, only polyethylene terephthalate film coated with liquid paraffin (average molecular weight 310) was also tested.

Table 2 shows the results of observing the state of adhesion of Al to the oil application part and the disturbance of the outer periphery of the oil application part of the film after vapor deposition.

[0031]

[Table 2]

As can be seen from Table 2, perfluoroalkylpolyether exhibits an excellent masking effect even when Al is vapor-deposited on various vapor-deposited substrates.

Furthermore, Zn and C other than Al are used as vapor deposition materials.
It was confirmed by a bell jar type vacuum deposition tester that perfluoroalkyl polyether can be preferably used as a masking oil even when vapor-depositing a metal such as u, Ni or Cr or an oxide conductor such as ITO.

Further, using a bell jar type vapor deposition tester, perfluoroalkyl polyether having an average molecular weight of 4,500, 5600 and 8400 was applied in place of the perfluoroalkyl polyether having an average molecular weight of 2500, and Al was vapor-deposited on the PET film as described above. I went the same way. As a result, a masking effect equivalent to that of the perfluoroalkyl polyether having an average molecular weight of 2500 was obtained. On the other hand, poly (trifluoromonochloroethylene) (average molecular weight 500, 700,
900, 1000, 3000), partially fluorinated silicone (800), polybutene (320), dioctylphthalate (390), dodecylbenzene (246), diisopropylnaphthalene (212), castor oil (432).
When used with, no sufficient masking effect was obtained as with the above liquid paraffin or silicone oil.

[0035]

As described above, according to the present invention,
By using perfluoroalkyl polyether as a masking oil when performing vacuum deposition while applying a non-deposited portion by the oil mask method, it is significantly superior to conventionally used masking oils such as paraffin oil and silicone oil. In addition, a masking effect comparable to that of the tape masking system can be obtained, and the problem of the patterning process by the tape masking system or the etching system can be eliminated. Then, a metallized film for a capacitor is suitably manufactured by using a conductive metal as a vapor deposition material.

[Brief description of drawings]

FIG. 1 is an internal front view of an apparatus for semi-continuous production of a metallized film for capacitors by vacuum deposition of an oil mask system.

FIG. 2 is a partial plan view of a metallized film for capacitors obtained by the above method.

FIG. 3 is a schematic diagram showing more details of the oil supply device used in the examples.

[Explanation of symbols]

 1: Raw film roll (2 ... its withdrawn state) 3: Cooling can 4: Evaporation product winding roll 5: Evaporation source 6: Oil supply device 7: Evaporation product (metallized film) 8: Evaporation part 9: Margin part 10: Transfer roll 11: Offset roll 12: Oil spray coating device

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location // H01G 13/00 391 C 7924-5E

Claims (1)

[Claims] 1. A plastic film is formed from an original roll.
Pattern masking oil to pull out and form non-metallized parts
It is applied like a ribbon and guided along the cooling metal roll surface.
Deposition the body metal and then depositing the deposited film in another position
Rolled up on a product roll with metallized film for capacitors
And a method for continuously producing
Performed in a vacuum vapor deposition machine and used the following formula as masking oil
(I)-(III) Formula (I)-(-C₃F₆O-)_n-Formula (II)-(-C₃F₆O-)_n-(-C F₂O
−)_m-Formula (III)-(-C₂F_FourO-)_n-(-C F₂O
−)_m-(Where n and m are all perfluoroalkyl polyethers
A flat body that gives an average molecular weight of 1,000 to 15,000
(Representing the number of uniform repeating units)
Each of them, or a mixture of two or more of them.
The compound of perfluoroalkyl polyether is
Direct contact application by transfer or printing to stick film
Of metallized film for capacitors characterized by
Build method.