JPH07241826A - Release film for manufacture of ceramic sheet - Google Patents

Abstract

PURPOSE:To prevent generation of cissing at the time of forming a thin ceramic layer by apply a ceramic slurry thinly, by forming a release layer on one face of a plastic film and forming thereon a polyvinylbutyral resin layer. CONSTITUTION:A release film which is optimum for manufacturing a ceramic sheet is made by forming a release layer on one face of a plastic film and forming a polyvinylbutyral resin layer on the release layer. The thickness of the polyvinylbutyral resin layer is set preferably to 3mum or less and the thickness of the release layer is set preferably to 1.0mm or less. For the release layer, a wax or an acrylic melamine resin is used. Further, for the plastic film, a polyester, a polypropylene, and a polycarbonate are used. Among them, particularly one having a heat shrinkage percentage of 1.0% or below under a condition of 150 deg.C for 30 minutes is used.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a releasable film for producing a ceramic sheet.

[0002]

2. Description of the Related Art As a release film for producing a ceramic sheet, a release film for producing a ceramic sheet in which a release layer is formed on one side of a plastic film has been conventionally known, and as a release layer, a silicone resin is used. The release layer made of is most commonly used (see Japanese Utility Model Publication No. 5-38884 and Japanese Patent Publication No. 3-4364). Then, the production of the ceramic sheet, after applying a ceramic slurry by a coating method such as screen printing on the release layer of the release film for producing a ceramic sheet and evaporating the solvent or water to form the ceramic layer, appropriate The release film was peeled from the ceramic layer while being cut into various sizes to obtain a ceramic sheet.

[0003]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention However, a release film for producing a ceramic sheet having a release layer made of a silicone resin is produced by thinly coating a ceramic slurry on the release layer to obtain a thin ceramic sheet. When a thin ceramic layer is formed, repelling occurs in the ceramic slurry. Further, when the ceramic layer becomes thin, it becomes difficult to peel the release film from the ceramic layer. In particular, considering the dimensional stability of the subsequent ceramic sheet during firing, it is necessary to reduce the amount of binder resin in the ceramic slurry, but the ceramic layer becomes brittle and cracks as the amount of binder resin in the ceramic slurry decreases. As the amount of binder resin is reduced, the release film becomes more difficult to peel from the ceramic layer. Therefore, a thin wiring layer may be formed by printing a thin wiring with conductive ink on the release layer of a release film for producing a ceramic sheet and then applying a ceramic slurry containing less binder resin by printing. Or, if you want to obtain a monolithic ceramic layer by stacking several ceramic layers by repeating hot pressing and peeling of the releasable film, prepare several sheets that have undergone through-hole processing. Although it is possible to perform through-hole processing in a state where the ceramic layer and the release film are integrated, when the release film is peeled from the ceramic layer to be laminated to obtain a laminated ceramic layer, the ceramic layer is The release film cannot be peeled off well from the ceramic layer because it is thin, fragile and easily cracked. Heat, it was impossible to laminate because less binder resin in the ceramic slurry in the crimping method by pressure. The present invention eliminates the above-mentioned drawbacks. Repelling does not occur even if a thin ceramic layer is formed by thinly applying a ceramic slurry, and the releasable film is peeled from a ceramic layer laminated by hot pressing. When the laminated ceramic layer is obtained by using, the release film can be easily peeled off without cracking the ceramic layer, and the dimensional stability of the produced ceramic sheet is also very good. It provides a film.

[0004]

DISCLOSURE OF THE INVENTION According to the present invention, a release layer is formed on one surface of a plastic film, and a polyvinyl butyral resin layer is formed on the release layer. It is a film. The present invention is
While the conventional release film for ceramic sheet production was one in which a release layer was simply formed on one side of a plastic film, a release layer was formed on one side of the plastic film and then polyvinyl butyral resin was added. A layer is formed. That is, the present invention, without simply forming a release layer on one side of the plastic film,
A layer in which a release layer and a polyvinyl butyral resin layer are laminated and integrated is formed with the release layer inside and the polyvinyl butyral resin layer outside. This polyvinyl butyral resin layer is laminated on the ceramic layer on the side to be laminated when the ceramic layer is laminated by repeating hot pressing and peeling of the release film. It functions as an adhesive with the ceramic layer on the side where it is formed, and also as a binder for the ceramic layer, especially for a thin ceramic layer coated with a ceramic slurry containing a small amount of binder resin. Due to the presence of the polyvinyl butyral resin layer, the releasable film can be easily peeled from the ceramic layer even if it is a thin ceramic layer coated with a ceramic slurry containing a small amount of binder resin.

As the plastic film, various plastic films such as polyester, polypropylene, polycarbonate, polyamide, polyethylene and fluororesin can be used. The plastic film preferably has a thermal shrinkage of 1.0% or less under the conditions of 150 ° C. and 30 minutes. Thermal shrinkage of plastic film is 1
If it is 1.0% or less under the condition of 50 ° C. for 30 minutes, the shrinkage of the plastic film due to the heat when the ceramic layer is dried and the heat and the pressure when the ceramic layers are laminated is extremely small, and the dimensional stability of the ceramic sheet is stable. It is possible to obtain sufficient sex.

Wax, acrylic melamine resin, silicone resin, metal oxide, fluororesin, etc. can be used for the release layer, but the adhesion of the ceramic layer is improved when the ceramic layers are laminated, and the plastic film is used as the ceramic layer. It is preferable to use wax or acrylic melamine-based resin for the release layer in order to completely peel it from the resin. The thickness of the release layer is preferably 1.0 μm or less. This is because, for example, when wax is used for the release layer, the thickness of the release layer is too thick when it exceeds 1.0 μm, and the adhesiveness of the ceramic layer tends to deteriorate when the ceramic layers are laminated. For example, when an acrylic melamine-based resin is used for the release layer, the thickness of the release layer is too thick when it exceeds 1.0 μm, and the acrylic melamine-based resin is cured and shrunk at the time of curing. This is because the curl becomes worse and the flatness tends to deteriorate.

By forming a release layer on one side of a plastic film and then forming a polyvinyl butyral resin layer, the release film for producing a ceramic sheet of the present invention can be obtained. When the release film is peeled from the ceramic layer in the production of the ceramic sheet, the release layer is integrated with the plastic film and separated from the ceramic layer, but the polyvinyl butyral resin layer is integrated with the ceramic layer. It is different from the plastic film. As described above, this polyvinyl butyral resin layer is on the surface of the ceramic layer on the laminated side when the hot pressing and the peeling of the release film are repeated to laminate the ceramic layers. It functions as an adhesive between the ceramic layer and the ceramic layer on the side to be laminated, and also as a binder for the ceramic layer, especially for a thin ceramic layer coated with a ceramic slurry containing a small amount of binder resin. Due to the presence of the polyvinyl butyral resin layer, the releasable film can be easily peeled from the ceramic layer even if it is a thin ceramic layer coated with a ceramic slurry containing a small amount of binder resin.

The thickness of the polyvinyl butyral resin layer is 3
It is preferably not more than μm. When the thickness of the polyvinyl butyral resin layer exceeds 3 μm, the so-called layering (filming) of the polyvinyl butyral resin layer becomes strong. Therefore, for example, a ceramic slurry is applied onto the polyvinyl butyral resin layer by screen printing to form a ceramic layer. After peeling the release film from the ceramic layer, the polyvinyl butyral resin layer in the portion where the ceramic layer is not formed is not cut off from the polyvinyl butyral resin layer in the portion where the ceramic layer is formed. Since it tends to remain attached to the polyvinyl butyral resin layer in the portion where the peeling is formed, the peeling property deteriorates and peeling failure easily occurs. Further, when the thickness of the polyvinyl butyral resin layer exceeds 3 μm, the adhesive force between the release layer and the polyvinyl butyral resin layer becomes too weak. Therefore, the ceramic slurry is applied onto the polyvinyl butyral resin layer by screen printing to form a ceramic layer. The polyvinyl butyral resin layer is easily peeled off from the plastic film on which the release layer is formed when forming the film.

[0009]

【Example】

Example 1 A wax containing a montan-based ester wax (Wax E manufactured by Hoechst Co., Ltd.) as a main component was heat-melted on one surface of a polyester film having a thickness of 75 μm, and the concentration was 0.5 with xylene.
What was diluted to 100% was coated with a gravure coater and dried at 100 ° C. to form a release layer having a thickness of 0.04 μm. Next, a polyvinyl butyral resin (Eslec BL-S manufactured by Sekisui Chemical Co., Ltd.) dissolved in MEK was applied onto the release layer with a gravure coater and dried at 100 ° C. to a thickness of 1.2 μm. A polyvinyl butyral resin layer was formed to obtain the release film for producing a ceramic sheet of the present invention. After that, heat treatment at 160 ° C for 5 minutes,
The heat shrinkage rate of the polyester film was adjusted to 0.7% or less under the condition of 150 ° C. for 30 minutes to obtain a releasable film for producing a ceramic sheet of the present invention.

Then, on the polyvinyl butyral resin layer of the releasable film for producing a ceramic sheet thus obtained, the weight ratio of the ceramic powder containing BaTiO ₃ as a main component, the polyvinyl butyral resin, the plasticizer and the solvent was adjusted. A ceramic slurry having a composition of 100: 3: 0.5: 100 was dried to a thickness of 100 μm and a size of 300 mm × 3.
A green layer as a base was formed by applying a size of 00 mm by screen printing to form a ceramic layer. In this case, repelling did not occur in the ceramic slurry at the time of forming the ceramic layer to be the green sheet. Further, the polyvinyl butyral resin layer was not separated from the release layer during the formation of the ceramic layer. on the other hand,
On the polyvinyl butyral resin layer of the release film for producing another ceramic sheet obtained as described above, A
g: Pd 80:20 conductive ink is used to print wiring by screen printing to a dry layer thickness of 3 μm.
The ceramic slurry is applied to the entire surface of the printed wiring by screen printing so as to have a dry layer thickness of 8 μm to form a ceramic layer, and a releasable film for producing printed wiring and the ceramic layer is obtained. It was In this case, cissing did not occur in the conductive ink and the ceramic slurry during the wiring printing and the formation of the ceramic layer. Further, the polyvinyl butyral resin layer was not separated from the release layer during the formation of the ceramic layer. After that, 10 pieces of the releasable film for manufacturing a ceramic sheet on which the wiring printing and the ceramic layer are formed and subjected to through-hole processing are prepared, and the 100 μm-thick green sheet is used to manufacture the first ceramic sheet. The release film is heat-pressed so that the ceramic layer contacts the green sheet, and then cooled to release the release film to peel off the polyester film and the release layer. The butyral resin layer was left on the green sheet. Further, the release film for producing a ceramic sheet on which the remaining 9 wiring prints and the ceramic layers have been formed in the same manner as above is repeatedly subjected to hot pressing and peeling, so that the wiring prints and the ceramic layers become 1
A laminated wiring printed ceramic layer laminated to 0 layer was obtained. In this case, peeling of the releasable film was very easy, the ceramic layers to be laminated were not cracked, and the peeling property was not deteriorated to cause peeling failure. Thereafter, the laminated wiring-printed ceramic layer laminated in 10 layers was peeled from the polyester film on which the green sheet was formed, calcined and fired at 1300 ° C. to manufacture a multilayer ceramic wiring-printed sheet. The produced multilayer ceramic wiring printed sheet has a small amount of components other than ceramics, so that the shrinkage during firing is small and the dimensional stability is good, and the thickness of the ceramic layer during wiring printing is 5 μm after firing, which is a very thin and dense layer. Was becoming.

Example 2 An acrylic melamine resin was applied to one side of a polyester film having a thickness of 100 μm in a dry layer thickness of 0.2 μm by a gravure coater to form a release layer, which was then formed on the release layer. , Polyvinyl butyral resin (Sekisui Chemical Co., Ltd. S-REC BL-2) dissolved in MEK, THF was applied with a gravure coater and dried at 100 ° C. to give a thickness of 2.0 μm.
A polyvinyl butyral resin layer having a thickness of 1 was formed to obtain a release film for producing a ceramic sheet of the present invention. Then, heat treatment is performed in the same manner as in Example 1 so that the heat shrinkage of the polyester film is 0.7% under the conditions of 150 ° C. and 30 minutes.
The release film for producing a ceramic sheet of the present invention was obtained by the following adjustments.

Using the releasable film for producing a ceramic sheet thus obtained, in the same manner as in Example 1, a laminated wiring-printed ceramic layer obtained by laminating five layers of wiring printing and ceramic layers was obtained. It was Also in this case, cissing did not occur in the conductive ink and the ceramic slurry during wiring printing and formation of the ceramic layer. Further, the polyvinyl butyral resin layer was not separated from the release layer during the formation of the ceramic layer. Further, peeling of the release film is very easy when obtaining a laminated wiring printed ceramic layer laminated in five layers, the laminated ceramic layers are not cracked, and the peelability is deteriorated to cause peeling failure. There was no. Thereafter, the laminated wiring-printed ceramic layers laminated in five layers were peeled off from the polyester film on which the green sheet was formed, calcined and fired at 1300 ° C. to manufacture a multilayer ceramic wiring-printed sheet. The produced multilayer ceramic wiring printing sheet had a small amount of components other than ceramics as in Example 1, so that shrinkage during firing was small and dimensional stability was good, and the thickness of the ceramic layer during wiring printing was 5 μm after firing. It was a thin and dense layer.

Comparative Example 1 A polyester film having a thickness of 75 μm has a thickness of 0.
A mold-releasing film for producing a ceramic sheet, which has a mold-releasing layer made of a silicone resin of 02 μm, was used.
Dry layer thickness 3 by screen printing with conductive ink similar to
Wiring is printed so as to have a thickness of .mu.m, and the same ceramic slurry as in Example 1 is applied to the entire surface of the wiring printing to form a dry layer thickness of 8
8μ thick when applied by screen printing to a thickness of μm
When an attempt was made to form a ceramic layer of m, cissing was generated in the conductive ink and the ceramic slurry during the wiring printing and the formation of the ceramic layer, and accurate printing could not be performed.

Comparative Example 2 A polyester film having a thickness of 75 μm has a thickness of 0.
A release film for producing a ceramic sheet having a release layer made of an amino-based copolymer resin of 01 μm.
No. 38888/1993) was used to manufacture a ceramic sheet in the same manner as in Example 1, but no cissing was generated in the conductive ink and the ceramic slurry during wiring printing and formation of the ceramic layer, but When a press-release film was repeatedly peeled off to obtain a laminated wiring-printed ceramic layer in which wiring printing and a ceramic layer were laminated, the peelability was poor and partial peeling failure occurred.

[0015]

According to the present invention constructed as described above, since the polyvinyl butyral resin layer is formed on the release layer, the wiring is printed with conductive ink or the ceramic slurry is thinly applied to form a thin ceramic layer. However, repelling does not occur in the conductive ink or the ceramic slurry. Further, the polyvinyl butyral resin layer has a light releasability from the release layer. Further, since the polyvinyl butyral resin layer functions as a binder for the thin ceramic layer coated with the ceramic slurry containing less binder resin, even if the thin ceramic layer coated with the ceramic slurry containing less binder resin has the release film, It can be easily separated from the thin ceramic layer. Therefore, when the laminated ceramic layer is obtained, even if the release film is peeled from the laminated ceramic layer, the ceramic layer can be easily peeled without cracking. Also, the dimensional stability of the produced ceramic sheet is very good. And, when the polyvinyl butyral resin layer of the present invention is laminated on the ceramic layer, the polyvinyl butyral resin layer is adhered to the laminated ceramic layer on the surface of the laminated ceramic layer and the laminated ceramic layer. By functioning as an agent, the ceramic layers can be more completely laminated. Also, since the polyvinyl butyral resin layer is a layer different from the ceramic layer,
It hardly affects the shrinkage of the ceramic layer during firing.

Claims (6)

[Claims] 1. A releasable film for producing a ceramic sheet, wherein a release layer is formed on one surface of a plastic film, and a polyvinyl butyral resin layer is formed on the release layer. 2. The polyvinyl butyral resin layer has a thickness of 3 μm.
The releasable film for producing a ceramic sheet according to claim 1, which has a thickness of m or less. 3. The release film for producing a ceramic sheet according to claim 1, wherein the thickness of the release layer is 1.0 μm or less. 4. The release film for producing a ceramic sheet according to claim 1, wherein the release layer is made of wax. 5. The release film for producing a ceramic sheet according to claim 1, wherein the release layer is made of an acrylic melamine resin. 6. The heat shrinkage rate of the plastic film is 150.
It is 1.0% or less under the condition of 30 ° C for 30 minutes.
The release film for producing a ceramic sheet according to any one of 1.