JPH03248582A - Manufacture of piezoelectric laminated actuator - Google Patents

Abstract

PURPOSE:To form an insulating layer simply and select the width and thickness of an insulating film properly, to prevent a mistake on conduction at the time of usage and to enable high-voltage conduction by applying a specific ultraviolet radiation curing type aerobic resin layer through screen printing as the insulating layer with a non-connected internal electrode under a conductor layer and curing and unifying the aerobic resin layer through the irradiation of ultraviolet rays. CONSTITUTION:Insulating films 3 composed of an ultraviolet radiation curing type aerobic resin having viscosity before curing of 10<4>cPs-10<6>cPs are formed to electrode layers 2 on every other layer of a pair of laminated end faces at the opposed positions of a laminate and near the electrode layers 2 through screen printing, and cured, and conductor layers 4 connecting the electrode layers 2 exposed on every other layer are applied and formed. The insulating layers 3 and the conductor layers 4 are formed in an asymmetric shape displaced in the direction of lamination on a pair of the laminated end faces. Accordingly, since the insulating layers consisting of the ultraviolet radiation curing type aerobic resin through screen printing are used, the insulating layers of a piezoelectric laminated actuator are shaped simply, the width and thickness of the insulating films 3 can be selected properly, a mistake on conduction at the time of usage is eliminated, and high-voltage conduction is enabled.

Description

[Detailed description of the invention]

[0001]

[Industrial application field]

The present invention relates to a method for manufacturing a piezoelectric laminated actuator suitable as an actuator for recording/reproducing actuators for VTR1 magnetic disk devices, optical disk devices, etc., precision valves, precision sample positioning mechanisms, dot impact printer heads, etc. [0002]

[Conventional technology]

The structure of the piezoelectric laminated actuator is, for example, as shown in Japanese Unexamined Patent Publication No. 58-196068, in which a piezoelectric ceramic plate and an internal electrode layer are laminated on a pair of laminated end faces at opposing positions of a laminated body in which internal electrode layers are alternately laminated. Conductor layers connecting every other internal electrode layer are provided in an asymmetrical manner shifted in the stacking direction on a pair of stacked end faces. A configuration is known in which an insulating coating is deposited on the electrode and its vicinity. [0003] In this configuration, the insulating coating is applied by screen printing. In addition, as a method for forming an insulating film having the above structure, the same applicant applied a photosensitive resin film to the side end surfaces of the laminate, and then exposed the photosensitive resin film to light and etched it to remove the negative part. proposed a method to
No. 196071). Furthermore, as a method for solving the problems of the above-mentioned printing method, a method has been proposed (Japanese Patent Laid-Open No. 175176/1983) in which electrophoresis is used to form an insulating film. [0004]

[Problem to be solved by the invention]

Screen printing has been proposed as a method for forming insulating coatings, but it is difficult to stably form fine insulating patterns when fluid insulating materials are used, so it is difficult to make use of the inherent advantages of screen printing. If thermosetting resins or high-temperature firing inorganic materials with low fluidity are used, the piezoelectric ceramics will be exposed to high temperatures during curing, leading to a decrease in piezoelectric properties or the lamination of piezoelectric ceramics. There are concerns that the adhesive used for integration may be adversely affected and the laminated structure may be damaged. [0005] In a configuration in which a photosensitive resin film is used as an insulating film, a pre-applied photosensitive resin film is masked at desired positions and exposed to light, and then the non-irradiated parts are etched away with an organic solvent. Since masking is performed in close proximity to the resin before curing during irradiation, there is a concern that the resin and the mask material may come into contact and form irregularities on the resin surface. [0006] Furthermore, if the resin and the mask material are separated too much, it becomes difficult to control the thickness and width of the resin, making it impossible to obtain a precise pattern. This not only complicates the work of applying an insulating film, but also makes it difficult to achieve today's miniaturization. It was not possible to provide a high-performance piezoelectric laminated actuator that satisfies the requirements of [0007] Furthermore, in a method of forming and depositing by electrophoresis, which has been proposed as a method to solve the problems of the above-mentioned printing method,
Baking is required in the post-process, the formation process is complicated and takes several days to manufacture, and since it is not possible to form a wide insulating coating, there is a risk of conduction during use. There was a problem in that the distance between the internal electrode surface and the conductor layer could not be increased due to the thickness of the insulating coating, and high voltage could not be applied. [0008] In view of the current situation, the present invention provides a piezoelectric laminated actuator in which the formation of an insulating layer is simple, the width and thickness of the insulating coating can be appropriately selected, there is no energization error during use, and high voltage energization is possible. The purpose of the present invention is to provide a method for manufacturing a piezoelectric laminated actuator that enables the provision of an actuator. [0009]

[Means to solve the problem]

In this invention, a conductor layer connecting every other layer of laminated internal electrode layers is attached to a pair of laminated end surfaces at opposing positions of a laminated body in which piezoelectric ceramic plates and internal electrode layers are alternately laminated. In the manufacturing method of a piezoelectric laminated actuator provided in an asymmetrical manner,
This method of manufacturing a piezoelectric laminated actuator is characterized in that an ultraviolet curable aerobic resin layer having a viscosity of 10 cps to 106 cps is deposited on a predetermined position by screen printing, and then cured and integrated by irradiation with ultraviolet rays. [00101

[Function] In the present invention, the method of applying an ultraviolet-curable aerobic resin layer by screen printing as an insulating layer is used because the formation process is easy and a precise pattern can be obtained. [0011] However, the ultraviolet curable aerobic resin, which is originally used for adhering and fixing electronic components, lead wires, etc., has a low viscosity of several hundred to several thousand and is fluid due to its function as an adhesive. Therefore, as mentioned above, there is no problem if it is coated on the entire required surface, but for patterning, known ultraviolet curing aerobic resins cannot be used as they are in screen printing. Therefore, the inventor conducted various studies on the viscosity that would enable screen printing without losing the original properties of the ultraviolet curable aerobic resin, and found that by selecting the resin composition, the resin had the desired viscosity before curing. It was discovered that a resin could be obtained, and the manufacturing method of the present invention was completed. [0012] In this invention, when performing screen printing,
The viscosity of the UV-curable aerobic resin layer before curing is 10 cp.
It is necessary to set it to s-106cps. That is, if the viscosity is less than 10 cps, the fluidity of the resin is too high, and if the viscosity exceeds 106 cps, the fluidity is poor, making it difficult to stably form a fine insulating layer pattern by screen printing. This is because it is difficult to control the thickness and width of the resin layer. The resin layers deposited on these predetermined positions are cured and integrated by irradiation with ultraviolet rays, usually for several seconds to several tens of seconds, depending on the resin composition, amount of deposit, etc. [0013] Disclosure Based on the Drawings FIG. 1 is a longitudinal cross-sectional view of a piezoelectric laminated actuator obtained by the manufacturing method of the present invention. A required amount of raw material powder for piezoelectric ceramic material is mixed, press-formed into a plate shape, and after sintering, on both sides of the piezoelectric ceramic plate 1, for example,
An electrode layer 2 is provided by Ni plating or the like, and several tens of piezoelectric ceramic plates 1 are laminated with adhesive, and the piezoelectric ceramic plates 1 and electrode layers 2 are laminated alternately by heating and pressurizing them to form a laminate. Nasu. [0014] In addition, every other electrode layer 2 and the vicinity thereof on a pair of stacked end faces located at opposing positions of the stacked body are made of an ultraviolet curable aerobic resin having a viscosity before curing of 10 cps to 106 cps by screen printing. After the insulating coating 3 is formed and cured, a conductive layer 4 is formed to connect every other exposed electrode layer 2. The insulating layer 3 and the conductor layer 4 are disposed asymmetrically at a pair of stacked end faces shifted in the stacking direction. [0015] Also, a metal paste such as platinum is screen printed on one side of a green sheet of piezoelectric ceramic material to form an internal electrode layer, so that piezoelectric ceramic plates and electrode layers 2 are alternately laminated.
It is also possible to laminate several tens of these piezoelectric ceramic plates to form a laminate, and then provide an insulating layer and a conductive layer using the method described above. [0016] Since the piezoelectric laminated actuator obtained by the manufacturing method of the present invention uses an insulating layer made of an ultraviolet curable aerobic resin by screen printing, it is easy to form the insulating layer of the piezoelectric laminated actuator, and the insulation coating width and The thickness can be appropriately selected, there is no energization error during use, and high voltage energization is possible. [0017] [Example] A required amount of raw material powder of a piezoelectric ceramic material containing zirconate titanate as a main component is blended, press-formed into a plate shape, and sintered to have a width of 5 mm, a length of 5 mm, and a thickness of 0.3 mm. A piezoelectric ceramic plate was obtained, and both sides of the piezoelectric ceramic plate were plated with Ni to a thickness of 1 μm.
60 piezoelectric ceramic plates were laminated with an adhesive, and heated and pressed at 1 kg/cm2 at 100°C for 1 hour to form an integrated piezoelectric ceramic plate and electrode layer. A laminate was obtained in which these were alternately laminated. [0018] Next, an ultraviolet curable aerobic acrylic resin having a viscosity before curing of 105 cps is applied by screen printing to every other electrode layer and its vicinity on the pair of stacked end faces located at opposing positions of the stacked body. An insulating film consisting of Sumikid (trade name, manufactured by Sumitomo Chemical Co., Ltd.) was applied and cured by irradiation with ultraviolet rays for 20 seconds to form an insulating film. [0019] As a conductor layer that connects every other exposed electrode layer, silver powder is kneaded into an ultraviolet curable aerobic acrylic resin (trade name: Sumikid, manufactured by Sumitomo Chemical Co., Ltd.) with a viscosity before curing of 105 cps to make it conductive. A conductive layer was formed by applying the resin to the exposed electrode layer and the outer peripheral surface of the laminate and curing it for 2 minutes. [0020] In FIG. 1, the insulation coating surface of the piezoelectric laminated actuator obtained by the manufacturing method of the present invention is 13=0.55±0.
．． 01mm, and the deviation of the center position from the electrode layer position was 20.01mm by screen printing technology.
could be controlled. The piezoelectric ceramic plate thickness, 11 = 0.3 mm, the electrode layer thickness, 12 = 0.002 mm, and the surface to be coated, 211 + 12 = 0.602 mm, so the uncoated portion is 14 = 0.026 ± 0.02 mm. Therefore, the ratio to the thickness of the piezoelectric ceramic plate is 14/11=0.087. Furthermore, even if the center position due to the screen printing method shifts and 14 becomes the maximum, 14/11 = 0.026 + 0.0
210.3=0.15. [0021]

【Effect of the invention】

In the piezoelectric laminated actuator obtained by the manufacturing method of the present invention, the uncovered portion is 1/6 or less of the thickness of the piezoelectric ceramic plate. By the way, in the formation of a glassy insulating film by the conventionally known electrophoresis method, 14/11 is usually 0.
．． It is about 75. From this, it can be seen that the ratio of the uncoated portion 14 to the piezoelectric ceramic plate thickness 11 is sufficiently small in the configuration based on the present invention compared to the prior art. It can be seen that the piezoelectric laminated actuator obtained by the manufacturing method of the present invention allows high voltage input and drastically reduces conduction errors. In addition, when manufacturing the piezoelectric laminated actuator according to the present invention, by using ultraviolet-curable aerobic acrylic resin for the insulating layer and conductor layer, manufacturing that conventionally required several days can be completed in just a few hours, resulting in increased manufacturing efficiency. It turns out that it is effective to hump on the top.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a piezoelectric laminated actuator obtained by the manufacturing method of the present invention.

[Explanation of symbols]

1 Piezoelectric ceramic plate 2 Electrode layer 3 Insulating coating 4 Conductor layer

【Document name】

drawing

[Figure 1]

Claims (1)

[Claims] Claim 1: A pair of laminated conductor layers connecting every other laminated internal electrode layer to a pair of laminated end faces at opposing positions of a laminated body in which piezoelectric ceramic plates and internal electrode layers are alternately laminated. In the manufacturing method of a piezoelectric laminated actuator provided asymmetrically on the end face, an ultraviolet curable aerobic resin layer with a viscosity of 10^4 cps to 10^6 cps is screen printed as an insulating layer with unconnected internal electrodes under the conductor layer. 1. A method for manufacturing a piezoelectric laminated actuator, characterized in that the piezoelectric laminated actuator is adhered to a predetermined position in a process and then cured and integrated by irradiation with ultraviolet rays.