JP2003093964A - Method for manufacturing release film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a release film which can remarkably reduce defective products occurring ratio by properly preventing contamination of dust and foreign matter between laminated layers in a ceramic capacitor. SOLUTION: In the method for manufacturing the release film including a process in which after a release agent liquid is applied onto at least one surface of a continuously carried polyester film, the film is dried and then is wound up in a roll shape, before winding up the dried film in the roll shape after drying the film, the release agent liquid applied surface of the polyester film is cleaned. Further in the method for manufacturing the release film including the process in which after the release agent liquid is applied onto at least one surface of the continuously carried polyester film, the film is dried, is wound up in a roll shape and then is cut to a prescribed width, after cutting the film to the prescribed width, the release agent liquid applied surface of the polyester film is cleaned.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a release film, and more specifically, by appropriately removing dust and foreign matter mixed in during the manufacturing process of a release film used for manufacturing a ceramic capacitor, the defect occurrence rate is improved. The present invention relates to a method for producing a release film in which the number is dramatically reduced.

[0002]

2. Description of the Related Art For ceramic electronic parts such as ceramic capacitors, for example, a flexible support (release film) is coated with a ceramic paint containing a ceramic powder, an organic binder, a plasticizer, a solvent, etc. by a doctor blade method or the like. And green sheet (unfired ceramic dielectric sheet)
Can be manufactured by a step of molding, and forming an electrode of palladium, silver, nickel or the like on it by screen printing. In particular, when obtaining a ceramic capacitor having a laminated structure, the obtained green sheets are laminated one by one so as to have a desired laminated structure, and a ceramic green chip is obtained through a press cutting process. The binder in the ceramic green chip thus obtained is burned out and fired at 1000 ° C to 1400 ° C,
Terminal electrodes made of silver, silver-palladium, nickel, copper or the like are formed on the obtained fired body to obtain a ceramic electronic component.

Further, as another technique for manufacturing a ceramic electronic component, there is a method of thermally transferring a green sheet so that the flexible support faces upward (Japanese Patent Laid-Open No. 63-188926), and flexible support. There has been proposed a method for obtaining a laminated body by repeating the step of forming a green sheet on the body and the step of printing electrodes on the green sheet by the required number of layers.

[0004]

One of the major problems in the production of ceramic electronic components, especially multilayer ceramic chip capacitors, which require many lamination steps as described above, is contamination by contamination such as dust and foreign matters. And
Prevention of such contamination is one of the important precautions in manufacturing. The multilayer chip capacitor has a laminated structure in which dielectric layers and electrode layers are alternately laminated as described above, and has a very small size of about several mm in both length and width, so it is very small. This is because the occurrence rate of defective products becomes extremely high even if dust or the like is mixed between the layers.

Specifically, in the step of forming a dielectric layer by applying a ceramic coating on a release film, or in the step of forming an electrode layer thereon, dust or foreign matter adheres to the release layer. In this case, in a ceramic capacitor obtained by repeating the lamination process without removing them, the occurrence rate of short-circuit defects increases.

Therefore, an object of the present invention is to solve the above problems and to appropriately prevent dust and foreign matter from being mixed between the laminated layers of the ceramic capacitor, so that the occurrence rate of defects can be dramatically reduced. It is to provide a method for producing a film.

[0007]

In order to solve the above-mentioned problems, the method for producing a release film of the present invention comprises applying a release agent solution to at least one side of a polyester film which is continuously conveyed, and then drying the solution. In the method for producing a release film including a step of winding in a roll shape, the polyester film release agent liquid application surface is cleaned after the drying and before the winding in the roll shape.

Another method for producing a release film of the present invention is to apply a release agent solution to at least one side of a polyester film that is continuously conveyed, dry it, and wind it into a roll, and then a predetermined width. In the method for producing a release film, which comprises the step of cutting into pieces, the release agent liquid-coated surface of the polyester film is cleaned after cutting to the predetermined width.

In the method for producing a release film of the present invention, it is preferable to clean both sides of the polyester film.

According to the present invention, after the release layer is formed, the ceramic capacitor manufactured by using the release film having at least the release agent liquid application surface cleaned is compared with the case where the release film without cleaning is used. The occurrence rate of short-circuit defects can be significantly reduced.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Specific embodiments of the present invention will be described in detail below. In the present invention, a release agent solution such as a silicone resin is applied on a resin film such as a polyester film and dried to form a release layer, and then the release agent solution application surface of the polyester film is cleaned. This may cause a short circuit failure,
It is possible to reliably prevent dust, foreign matter, and the like from entering the inside of the ceramic capacitor during manufacturing, and it is possible to significantly reduce the defect occurrence rate.

For cleaning, the polyester film is continuously conveyed to form a release layer on at least one side,
In the manufacturing process of the release film wound into a roll,
The release agent liquid is applied and dried, preferably dried and cured to form a release layer, and then, before the roll is wound. The wound-up roll is then transferred to a separately provided step, re-fed out, and subjected to a manufacturing step of a ceramic capacitor in which a dielectric layer and an electrode layer are formed on the surface of the release layer by coating and printing. Therefore, cleaning
Most preferably, it is performed immediately after winding after the peeling layer is formed.

Further, when the width of the device for applying the release film is wider than that of the device for applying the dielectric layer, the release film is formed and wound up, and then peeled so as to match the applied width of the dielectric layer. A slit process of cutting the film into a predetermined width is performed. In this case, cleaning is performed after cutting the film into a predetermined width by the slit process. This is because it is preferable to perform cleaning immediately before the step of applying the dielectric layer or the like as much as possible in order to reliably remove dust and foreign matter.

Cleaning of the polyester film (release film) after formation of the release layer is required to be performed on the surface on which the release agent liquid is applied, but it is preferably performed on both surfaces. That is, when forming the release layers on both sides, it is naturally necessary to perform cleaning on both sides, but it is preferable to clean both sides even when the release layer is formed on only one side. In the case of one side, dust and the like can be prevented at least by cleaning only the surface where the release layer is formed, but if dust or foreign matter is attached to the side where the release layer is not formed, take up the roll etc. Since the peeling layer may be contaminated again during the step (2), it is preferable to perform it on both sides.

In a ceramic capacitor, a ceramic coating is applied on a release layer of a release film to form a dielectric layer, an electrode layer is printed on the dielectric layer, and the step of forming the two layers is performed at least once. Repeating the above, it is produced by laminating the dielectric layer and the electrode layer on the release layer of the release film, but in the present invention, preferably, as described above, the release layer surface immediately after winding after the release layer is formed. The cleaning is effective, so the cleaning is effective.

The cleaning method may be either a contact type or a non-contact type, and for example, the contact type cleaning method shown in FIG. 1 or the non-contact type cleaning method shown in FIG. 2 can be used. Both FIG. 1 and FIG. 2 show how a film provided with a release layer on the upper surface side is conveyed. In the case of the contact type as shown in FIG. 1, a non-woven fabric is generally used as a cleaning material, and care should be taken to prevent scratches on the film. Specifically, as shown in the drawing, a feeding roll 3 in which a nonwoven fabric 2 is wound in a roll shape
It is preferable to use an apparatus having a winding roll 4 for winding the unwound nonwoven fabric 2 and a guide roll 5 for pressing the nonwoven fabric 2 against the surface of the film 1. This device needs to be installed only on at least the surface of the film on the side where the release layer is formed, but it is preferably installed on both surfaces as shown in FIG. Further, the guide roll 5 preferably has a structure capable of changing its position so that the pressing strength against the film 1 can be adjusted. By changing the position, the peeling layer or the surface of the polyester film is not damaged. Thus, it becomes easy to efficiently collect dust and the like.

In the case of the non-contact type shown in FIG. 2, while the film 1 is being conveyed through the guide roll 6 as shown in the drawing, a cleaning device 7 such as a web cleaner is used.
Use to clean. The illustrated web cleaner is a cleaning method of a type that includes a high-speed air blowing mechanism and a vacuum suction mechanism, blows air at high speed to remove fine particle size dust and foreign matter adhering to the film surface, and sucks and removes this.

It should be noted that any of the cleaning methods shown in the figures is extremely effective for improving the yield of products that are extremely small in size, such as a multilayer chip capacitor, and that are laminated in many layers.

[0019]

Example 1 <Preparation of release agent liquid> A type of curing in which a platinum-based catalyst is added to a mixture of a vinyl group-containing polydimethylsiloxane and a hydrogensilane-based compound to carry out an addition reaction in the following formulation. Type silicone (manufactured by Shin-Etsu Chemical Co., Ltd.
KS-847 (H)) with methyl ethyl ketone (MEK)
Release agent liquid (silicone resin solution) with a total solids concentration of 3.0 wt% dissolved in a mixed solvent of toluene and toluene
Was prepared. Shin-Etsu Chemical Co., Ltd. product name: KS-847H 300 g (solid content concentration 30%, resin 90 g) Platinum catalyst CAT-PL-50T (Shin-Etsu Chemical Co., Ltd.) 3.0 g MEK / toluene = 50/50 (Weight ratio) solution 2700g

<Preparation of coating for dielectric layer> Particle size: 0.1 μm
After firing powder of barium titanate, chromium oxide, yttrium oxide, manganese carbonate, barium carbonate, calcium carbonate, silicon oxide, etc. having a thickness of about 1.0 μm, BaTiO ₃
As 100 mol%, 0.3 mol% converted to Cr ₂ O ₃ , 0.4 mol% converted to MnO, 2.4 mol% converted to BaO, and 1.6 mol converted to CaO. %, SiO
4 mol% when converted to ₂ , 0.1 mol% when converted to Y ₂ O ₃
The resulting mixture was mixed so as to have the composition described above, mixed by a ball mill for 24 hours, and dried to obtain a dielectric material. 100 parts by weight of this dielectric material, 5 parts by weight of acrylic resin, 40 parts by weight of methylene chloride, 25 parts by weight of acetone, and 6 parts by weight of mineral spirit were blended, and commercially available φ10 mm zirconia beads were used to form a pot stand. Mix for 24 hours,
A dielectric ceramic paint (dielectric layer paint) was obtained.

<Preparation of release film>
Using a bar coater, apply it to a biaxially stretched polyethylene terephthalate (PET) film with a width of 100 mm and a thickness of 38 μm so that the coating film thickness after drying will be 0.15 μm, and dry and cure for 40 seconds at a heating temperature of 110 ° C. Was done. After that, a nonwoven fabric (Fuji Spinning Co., Ltd., POLYPAS) was used to clean both sides of the film by the contact type cleaning method shown in FIG.
A release film wound into a roll was obtained.

<Formation of Dielectric Layer> Next, using a doctor coat method, a dielectric layer coating material is applied to the release agent liquid application surface of the release film so that the dielectric layer thickness after drying is 8 μm. It was dried at 70 ° C. for 20 seconds and wound into a roll to form a dielectric layer (green sheet).

<Printing of electrode layer> Subsequently, an electrode pattern was printed on the dielectric layer. A material containing nickel and copper as main components was used for the electrodes. The electrode pattern was such that individual electrodes were arranged at intervals in the horizontal and vertical directions.

<Peeling / Laminating Step> After the above-mentioned dielectric layer forming step and electrode layer printing step were carried out, the dielectric layer and the electrode layer were peeled from the release film. Seventy-five green sheets with electrodes thus obtained were produced, and these were laminated in a number of 75 layers.

<Preparation of multilayer ceramic chip sample> The multilayer green sheet obtained as described above was punched, pressed and cut to obtain a multilayer ceramic chip. The obtained multilayer ceramic chip was debindered at 280 ° C. for 12 hours and fired at 1300 ° C. for 2 hours in a reducing atmosphere. A terminal electrode was formed on the laminate obtained after firing. The material of the terminal electrode was copper as a main component. This was baked in a mixed gas atmosphere of nitrogen and hydrogen at 800 ° C. for 30 minutes and plated to obtain a multilayer ceramic chip sample.

Example 2 Instead of the non-woven fabric as the contact type cleaning method, as shown in FIG.
A multilayer ceramic chip sample was prepared in the same manner as in Example 1 except that the air-blowing type non-contact cleaning method (web cleaner) shown in was used.

Example 3 In the step of forming a peeling layer, a PET film having a width of 1000 mm was used, and after the peeling layer was formed, a roll of the film once cut into 100 mm width with a slitter and before being wound into a roll again. A laminated ceramic chip sample was produced in the same manner as in Example 1 except that the same cleaning was performed.

Example 4 In the step of forming a peeling layer, a PET film having a width of 1000 mm was used, and after the peeling layer was formed, a roll of the film once cut into 100 mm width with a slitter and before being wound into a roll again. A laminated ceramic chip sample was prepared in the same manner as in Example 2 except that the same cleaning was performed.

Comparative Example A laminated ceramic chip sample was prepared in the same manner as in Example 1 except that cleaning was not performed at all.

Short-circuit defect rate High resistance meter HP-4329 manufactured by Hewlett-Packard Co.
Using A, 10 V was applied at 20 ° C., and the resistance value was measured after 30 seconds. A test piece having an insulation resistance of 1000Ω or less was defined as a short circuit failure, and the ratio of the number of short circuit failure occurrences to the number of samples provided for the test was displayed as a short circuit failure rate for each sample. The results are shown in Table 1 below.

[0031]

[Table 1]

[0032]

As described above, according to the method for producing a release film of the present invention, the incidence of defects is significantly increased by appropriately preventing the inclusion of dust, foreign matter, etc. between the laminated layers of the ceramic capacitor. Can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of a contact type cleaning method according to the present invention.

FIG. 2 is a schematic view showing an example of a non-contact cleaning method according to the present invention.

[Explanation of symbols]

1 film 2 Cleaning material (nonwoven fabric) 3 Feeding roll 4 winding roll 5,6 guide roll 7 Cleaning device

Claims (3)

[Claims] 1. A method for producing a release film, which comprises the steps of applying a release agent solution to at least one surface of a polyester film that is continuously conveyed, drying the roll, and winding the roll into a roll. The method for producing a release film, which comprises cleaning the release agent liquid-coated surface of the polyester film before winding the film. 2. A method for producing a release film, which comprises the steps of applying a release agent solution to at least one surface of a polyester film that is continuously conveyed, drying it, winding it into a roll, and cutting it into a predetermined width. A method for producing a release film, which comprises cleaning the release agent liquid application surface of the polyester film after cutting the predetermined width. 3. The method for producing a release film according to claim 1, wherein both surfaces of the polyester film are cleaned.