JPS6042606B2 - Manufacturing method for ultra-thin ceramic capacitors - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Object of the Invention) The present invention relates to a method for manufacturing ultra-thin ceramic capacitors used in electronic wristwatches, wireless communication devices, cameras, calculators, and the like.

The purpose of this invention is to efficiently manufacture ultra-thin ceramic capacitors.

A further object is to facilitate manufacturing and to obtain any shape. (Prior art) Conventionally, this type of thin ceramic capacitor was made by rolling the material thinly using a roll forming method, punching it into the desired shape using a punching machine, etc., and then drying and firing it. Not only is it difficult to spread, and the manual handling during drying and firing of this ultra-thin molded product is extremely difficult, but the molded product is easily deformed, resulting in a high product defect rate, and It had a low stopping speed, and I couldn't hope for a cheap product.

Moreover, ultra-thin products were unthinkable. (Structure of the Invention) In view of the above-mentioned problems, the present invention is manufactured based on a technology completely different from the conventional one, in which a material is printed in a desired shape on a substrate such as transfer paper using screen printing technology, and then a resin is coated on the material. This was an attempt to obtain an ultra-thin capacitor by drying and firing the layered product.

The dielectric material constituting the capacitor is BaO.
4T1O,,TIO. etc. or a combination of both is known. It is also known that temperature compensation systems are composed of TiO2 and various titanates as main components, and high dielectric constant systems are composed of BaT1O3 as a main component and stannate and zirconate as subcomponents. To further explain the present invention in detail based on examples, barium titanate particles with a particle size of 8 μm or less cause powders with a particle size of 80% or more, and powders with a particle size of 180% or less to cause fluctuations in particle size, so they are not patterned after printing.゛mura'
' is produced.

A paste-like ink was prepared by stirring and kneading 8 parts of the dielectric material consisting of the above and 20 parts by weight of a known vehicle (for example, a 15% organic solution of ethyl cellulose) using a mixer, a three-roller mill, or the like. Then, as shown in the figure, using this ink, a circular pattern 2 having a thickness of 10 to 301 LmN, preferably 20 to 24 μm, was printed on a substrate 1 such as a plastic film or transfer paper by screen printing. Depending on the thickness, a silk screen, nylon screen, or mesh metal screen can be used to print in the desired shape. After printing of the dielectric material is completed, a coating layer 3 is provided by a screen printing method using a synthetic resin mainly composed of acrylic resin so as to cover the entire surface of the pattern.
The screen printing method is a well-known method, in which a screen frame made from a screen frame that is slightly larger than the entire surface of the capacitor pattern previously printed on a substrate such as a plastic film or transfer paper, or a screen frame slightly larger than the pattern is attached to the printing machine, and the synthetic resin liquid is applied to the screen frame. The substrate under the mesh frame is coated with the synthetic resin by placing it on top and rubbing it with a squeegee (rubber spatula). When this is dried, the desired coating layer is obtained. Let it dry completely,
By raising the temperature to about 1230°C, holding the powder at 1230°C, and slowly cooling it, an element body for an ultra-thin ceramic capacitor can be obtained. Using this element, a ceramic capacitor can be manufactured by attaching electrodes in a conventional manner. (Operations and Effects of the Invention) Conventionally, a compounded raw material made of a dielectric material is made into a granulated raw material using a spray dryer or the like, and this is press-molded to form a molded product.

Alternatively, an organic binder is added to the blended raw materials, a green sheet is made using an extruder, and a molded product is formed using a punching machine.
The ceramic capacitor was made by firing at a high temperature of °C, baking the electrodes, and processing the lead wires. The present invention uses dielectric fine powder of a material for ceramic capacitors, cellulose resin,
A paste-like ink kneaded with a known vehicle or solvent such as acrylic resin is screen printed onto a substrate such as a plastic film or transfer paper in the desired shape, a synthetic resin coating layer is applied, and the film is dried and fired. Since this is a unique manufacturing method for ultra-thin ceramic capacitors, it is possible to obtain capacitors with a thickness of 1 μm or less, thereby increasing the capacitance of the capacitor.

With conventional mechanical methods, it has been impossible to reduce the thickness of the element body to 100 pm or less. Furthermore, conventional manufacturing methods involve complicated factors such as moldability, firing conditions, etc., but according to the present invention, molding is easy due to the use of screen printing and the use of plastic film or transfer paper as the printing substrate. Moreover, it has the great advantage that various arbitrary shapes can be obtained.

Furthermore, it becomes possible to mold extremely thin ceramic capacitors, and handling after molding becomes easy, and there is almost no deformation of the product. Additionally, it has become possible to fire at a lower temperature than before. In this way, ultra-thin ceramic capacitors used in electronic wristwatches, wireless communication devices, cameras, calculators, etc. can now be manufactured easily, inexpensively, and with high yield, which has a tremendous effect.

[Brief explanation of the drawing]

The drawing is a partially cutaway plan view of a product according to the present invention. Explanation of symbols of main parts, 1...Base, 2...
...Circular pattern, 3...Coating layer.

Claims (1)

[Claims] 1 Screen print a paste ink prepared by kneading dielectric fine powder of a ceramic capacitor material with a known vehicle or solvent such as cellulose resin or acrylic resin on a substrate such as a plastic film or transfer paper into the desired shape, A manufacturing method for ultra-thin ceramic capacitors, which is characterized by applying a coating layer using synthetic resin, the main component of which is acrylic resin, and then firing it after drying.