JPH04184847A - Partial pressure resistance element for installation in electron tube - Google Patents

Abstract

PURPOSE:To prevent variation in the resistance value of a resistance layer by forming a barrier layer of metal oxide through hydrolysis of an organic metal compound layer including metal alkoxide, and locating this barrier layer between the resistance layer and an insulative covering layer. CONSTITUTION:Terminal parts 7, etc., are provided on an insulated base board 15 made of ceramic, and each terminal part 7 is composed of an electrode layer 16 and an extraction electrode 17. Between these terminal parts a resistance layer 19 is formed, which is obtained by printing, drying, and baking a resistance material consisting of glass yarn and RuO2 having a certain specified resistance value. In such a way as enclosing this resistance layer 19 an insulative covering layer 20 is formed, and a barrier layer 21 is provided between these layers 19, 20. This barrier layer 21 is to prevent the Pb contained in the layer 20 from eluding into the layer 19 and consists of metal oxide which is formed through hydrolysis of an organic metal compound layer such as metal alkoxide. Thereby change in the resistance value due to elusion of Pb component can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a voltage dividing resistor element built into an electron tube such as a color cathode ray tube.

(Prior Art) Conventionally, some electron tubes, such as color cathode ray tubes used in color television receivers, require a high voltage to be supplied to convergence electrodes, focus electrodes, etc. in addition to the anode voltage.

In such a case, if a high voltage is supplied from the stem of the color cathode ray tube, a problem will arise in terms of withstand voltage, so a voltage dividing resistor is built into the color cathode ray tube together with the electron gun as a voltage dividing resistor element for the built-in electron tube. A method has been proposed in which the anode voltage is divided into parts to supply a high voltage to each electrode.

An example of a color cathode ray tube (near the electron gun) incorporating this type of voltage dividing resistor element is shown in FIG. Reference numeral 1 in the figure is a tube body, and an electron gun structure 2 is disposed within the neck portion a of this tube body 1.
For each cathode K, the first grid electrode G1,
Second grid electrode G2, third grid electrode G3, fourth grid electrode G4, fifth grid electrode G5, sixth grid electrode G6, seventh grid electrode G7, eighth grid electrode G
8 are sequentially arranged on the same axis, and the convergence electrode 3 is arranged after the eighth grid electrode G8. Each grid electrode G1, G2, G3, G4, G5, G6, G7
and G8 are mechanically held by the bead glass 4 while maintaining a predetermined positional relationship with each other. Further, the third grid electrode G3 and the fifth grid electrode G5 are electrically connected by a conducting wire 5, and furthermore, the convergence electrode 3 is electrically connected to the eighth grid electrode G8 by welding.

A voltage dividing resistor element 6 is attached to such an electron gun assembly 2, and the voltage dividing resistor element 6 is provided with a plurality of terminal portions 7,8,9,10,11. and,
Each high-voltage lead-out electrode of the terminal section 8.9.10 is connected to the fifth grid electrode G5, the sixth grid electrode G6, and the seventh grid electrode G7. Further, the lead electrode of the terminal portion 11 is connected to the convergence electrode 3, and the lead electrode of the terminal portion 7 on the ground side is connected to the ground electrode pin 12 embedded in the stem portion IC.

On the other hand, a graphite conductive film 13 is attached to the inner wall of the funnel part 1b of the tube body 1, and extends to the inner wall of the neck part 1a. (not shown).

The convergence electrode 3 is provided with a conductive spring 14, and when the conductive spring 14 comes into contact with the graphite conductive film 13, the terminal portions of the convergence electrode 3, the eighth grid electrode G8, and the voltage dividing resistor element 6 are connected. 11 is supplied with an anode voltage, and the high voltage terminal section 8
．． 9. The divided voltage generated at 10 is the seventh grid electrode G.
7, supplied to the sixth grid electrode G6 and the fifth grid electrode G5.

The voltage dividing resistance element 6 built into such a color cathode ray tube is constructed as shown in FIGS. The voltage dividing resistor element 6 is shown as seen from above, and (b) is B-
A sectional view taken along line B', and (c) a partially enlarged view.

That is, an insulating substrate 1 made of ceramic such as aluminum oxide
5 has a plurality of terminal sections 7.8.9.10 as described above.
．． 11 are provided. As shown in FIG. 7(c), the terminal portion 7 consists of an electrode layer 16 and an extraction electrode 17, which are formed by printing, drying, and firing an electrode material made of, for example, RuO2 and glass, and the extraction electrode 17 is formed on an insulating substrate 15. The through hole 18 passing through is caulked from above and below. Note that the other terminal portions 8.9.10.11 are similarly configured. Each such terminal section 7.8.9.10.1
1, a resistive layer 19 is formed by printing, drying, and baking a resistive material made of RuO2 and glass having a predetermined resistance value in a zigzag pattern. Furthermore, this resistance layer 1
An insulating coating layer 20 is formed to cover 9.

The conditions required for such a voltage dividing resistor element 6 for built-in electron tubes are: ■ It must be stable during the heating process and pressure resistance treatment process during the manufacturing process of color cathode ray tubes; ■ It must have a resistance value due to Joule heat generated during operation. ■ It does not become a secondary electron emission source when it is hit by scattered electrons; ■ It does not disturb the electric field distribution of the electron gun, causing discharge or shifting the trajectory of the electrons. Can be mentioned.

(Problem to be Solved by the Invention) By the way, when the conventional voltage dividing resistor element 6 is built into a color cathode ray tube and used under high voltage for a long time, the lead component in the insulating coating layer 20 enters the resistive layer 19. Elution, resistance layer 19
This has the disadvantage that a change in resistance value occurs, and a change in the division ratio, which is an important characteristic of a voltage dividing resistor element, occurs.

This invention was made in view of the above circumstances, and prevents the lead component in the insulating coating layer from leaching into the resistance layer, and prevents fluctuations in the division ratio even when used for long periods of time under high voltage. It is an object of the present invention to provide a voltage dividing resistor element for incorporating a small number of electron tubes.

[Structure of the Invention] (Means for Solving the Problems) The present invention includes forming a resistance layer containing lead ruthenate and having lead borosilicate glass as a main component on an insulating substrate made of ceramics. In the partial voltage resistor element 1 for built-in electron tube, which has an insulating coating layer formed thereon, between the resistive layer and the insulating coating layer, the lead component contained in the insulating coating layer is eluted into the resistive layer. A barrier layer is provided to prevent this, and this rear layer is a metal oxide layer formed by hydrolysis of an organometallic compound layer containing a metal alkoxide, and is a partial voltage resistance element for use in an electron tube.

The metal alkoxide has the general formula: M(OR)x (where M represents a metal, 0 represents oxygen, and R represents 1
X represents the valence of M), where M is S t sAl, Su, T
Examples include a5Ti, and particularly when M is S1SAl, it is highly effective as a barrier layer.

Examples of such metal alkoxides include triethoxyaluminum, triisopropoxyaluminum,
Examples include tetraethoxy silicon, tetraethoxy tantalum, tetraisobroquititanium, tetra-n-propoxytitanium, polymers thereof, and mixtures thereof.

(Function) According to the present invention, between the resistance layer formed on the ceramic insulating substrate and the insulating coating layer formed on this resistance layer, the metal Since a barrier layer consisting of an oxide layer is formed against the elution of lead components, the lead components in the insulating coating layer will not elute into the resistance layer even during long-term use under high voltage. It is possible to prevent changes in resistance value due to elution of .

As a result, a highly reliable voltage dividing resistor element for built-in electron tube can be obtained.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

The voltage dividing resistor element for built-in electron tube according to the present invention is shown in FIG.
It is configured as shown in a), (b), and (c), where (a) is a plan view showing the state seen through from above the insulating coating layer forming the outer surface, and (b) is a plan view taken along the line A-A'. (c) is a partially enlarged view.

That is, the same parts as in the conventional example (Fig. 3) are designated by the same reference numerals. The reference numeral 15 in the figure is an insulating substrate made of ceramic such as aluminum oxide, and on this insulating substrate 15, there are A plurality of terminal portions 7.8.9.10.11 are provided. As shown in FIG. 2C, the terminal portion 7 is made up of an electrode layer 16 and an extraction electrode 17 made of printed, dried, and fired electrode materials made of, for example, RuO2 and glass. The penetrating through hole 18 is caulked from above and below. Note that the other terminal portions 8.9.10.11 are similarly configured.

Between each terminal part 7.8.9.10.11, there is a resistive layer 1 in which a resistive material made of RuO2 and glass having a predetermined resistance value is printed in a zigzag pattern, dried, and fired.
9 is formed. Furthermore, an insulating coating layer 20 is formed to cover this resistance layer 19, but in this invention,
A barrier layer 21 is provided between the resistance layer 19 and the insulating coating layer 20. This barrier layer 21 is an insulating coating layer 20
This layer is provided to prevent the lead component contained therein from eluting into the resistance layer 19, and is made of a metal oxide layer formed by hydrolysis of an organic metal compound layer such as a metal alkoxide.

Next, a method of manufacturing a voltage dividing resistor element for use in an electron tube according to the present invention will be explained.

First, the insulating substrate 15 mainly contains aluminum oxide with a purity of 96% or more, and also contains silicon oxide and magnesium oxide.
An electrode layer 16 containing lead ruthenate and having lead borosilicate glass as a main component is formed on the insulating substrate 15, which contains sodium oxide and potassium oxide as impurities. In order to reduce the contact resistance with the metal extraction electrode 17 that will be attached later, this electrode layer 16 is made by increasing the ratio of lead ruthenate in the lead borosilicate glass so that the resistance value is about IOKΩ/mouth. Using adjusted resistance paste material.

This resistance paste material is printed in a predetermined pattern shape using a screen printing method. After that, 100-120
The paste is dried at a temperature of °C to remove the solvent components contained in the paste.

Next, a resistance layer 19 containing lead ruthenate and having lead borosilicate glass as a main component is formed on the insulating substrate 15. This resistive layer 19 is made of a resistive paste made of a resistive paste adjusted to about 1 to 10 MΩ/hole by reducing the ratio of lead ruthenate in lead borosilicate glass to obtain a resistance value of about 2 to 3 GΩ as a resistor. materials used.

This resistance paste material is printed in a predetermined pattern shape using a screen printing method. After that, 100-120
The paste is dried at a temperature of °C to remove the solvent components contained in the paste.

Next, the above electrode layer 16 and resistance layer 19 were
00℃, a more preferable temperature range is 840-860℃
C. in the air for about 5 to 15 minutes, more preferably 8 to 10 minutes.

Next, the resistance value of the formed resistance layer 19 is measured, and if the division ratio is not within a predetermined range, the division ratio is adjusted to a predetermined division ratio by a trimming process.

Next, 5in2 or AI! obtained by hydrolysis of metal alkoxide is placed on the resistance layer 19 so as to cover the resistance layer 19. 20. A barrier layer 21 consisting of the following is formed.

As a method for forming this barrier layer 21, for example, as a metal alkoxide, Al (0-isociHs)4 or S l (OC2H5) a ... (1)
The insulating substrate 15 is immersed in a solution containing (this metal alkoxide solution may contain not only monomers but also polymers with different degrees of polymerization), pulled up at a constant speed, and heated at 100 to 60°C in the atmosphere. For example, 150℃ x 10 minutes + 4
00@CX Heat treatment and baking for 30 minutes.

The reaction for forming the metal oxide layer at this time is considered as follows.

The insulating substrate 15 is immersed in a coating solution containing a metal alkoxide, and when pulled up, H2O in the atmosphere causes a hydrolysis reaction as shown in equation (2) below and as shown in equation (3). The polymerization reactions proceed in a complex and intertwined manner, and at the end of the pulling process, a film containing 10H groups is formed on the surface of the substrate, and at the same time, alcohol is produced.

By heating this to 100 to 600°C, the generated alcohol and -OH groups are decomposed and volatilized, forming a strong metal oxide layer.

The thickness of the metal oxide layer to be formed can be controlled by adjusting the viscosity of the metal alkoxide solution, the mixing ratio of monomer and polymer, the presence or absence of additives, the pulling rate, etc.

Next, an insulating coating layer 20 containing lead borosilicate glass as a main component is formed on the metal oxide layer, that is, the barrier layer 21 .

Since this insulating coating layer 20 is used under high voltage in a color cathode ray tube, it must have excellent voltage resistance. Moreover, in order to increase the voltage resistance of the insulating coating layer 20,
The film thickness after firing is approximately 200 to 400 μm.

The above-mentioned insulating coating material is prepared in the form of a paste, which is printed in a predetermined pattern shape using a screen printing method. Thereafter, the paste is dried at a temperature of 100 to 200°C to remove the solvent component contained in the paste.

Next, this insulating coating layer 20 is heated in the air at a temperature of 500 to 700°C, more preferably 570 to 630°C, for about 5 to 15 minutes, more preferably 80 minutes.
Heat for ~10 minutes and bake.

Next, a metal extraction electrode 17 is fixed by caulking to the through hole 18 of the insulating substrate 15 located at the center of the electrode layer 16 to establish electrical continuity with the electrode layer 16. At this time, by sufficiently caulking, the extraction electrode 17 penetrates the barrier layer 21 and is fixed to the electrode layer 16, thereby obtaining sufficient conduction. Note that these steps are performed for each terminal portion 7.8.9.10.11.

Now, the voltage dividing resistor element of the present invention and the conventional voltage dividing resistor element obtained in this way are made to have a total resistance value of about 30Ω, and in a vacuum of lX10-' to lX10-' Torr,
DC50K to the resistor connected to convergence electrode 3 (split ratio is 40%) and between the resistor connected to the ground terminal
A voltage of V was applied and the device was operated for 10 to 30 hours.

In the conventional voltage dividing resistor element, the resistance value changed as early as 10 hours, and the resistance value rapidly decreased after 20 hours. However, in the voltage dividing resistive element of the present invention, there is almost no change in resistance value even after 30 hours of application.

Also, after finishing, the cross section of the voltage dividing resistor element of this invention was subjected to EPMA
As a result of investigation, it was found that from the insulating coating layer 20 to the resistive layer 19
No migration of lead components was observed.

[Effects of the Invention] According to the present invention, since the barrier layer prevents the lead component in the insulating coating layer from leaching into the resistance layer, it is possible to prevent fluctuations in the resistance value of the resistance layer. Therefore, it is possible to provide a voltage dividing resistor element for use in an electron tube with excellent lifetime characteristics and less variation in division ratio due to changes in resistance value.

[Brief explanation of the drawing]

FIGS. 1(a), (b), and (c) show a partial voltage resistance element for built-in electron tube according to an embodiment of the present invention, and (a) shows a state seen through from above the insulating coating layer forming the outer surface. (b) is a cross-sectional view taken along the line A-A', (c
) is a partially enlarged view, Figure 2 is a sectional view showing the main parts of a general color cathode ray tube (near the electron gun structure), and Figure 3 (a)
, (b), and (C) show a conventional voltage dividing resistor element for built-in electron tubes, (a) is a plan view showing a state seen through from above the insulating coating layer forming the outer surface, and (b) is a plan view showing the state seen through from above the insulating coating layer forming the outer surface. A cross-sectional view taken along the line ', and (c) a partially enlarged view. 15... Insulating substrate, 19... Resistance layer, 20... Insulating coating layer, 21... Barrier layer. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Claims] Contains lead ruthenate on a ceramic insulating substrate,
In a partial voltage resistance element for built-in electron tubes, in which a resistance layer mainly composed of lead borosilicate glass is formed, and an insulating coating layer is formed on this resistance layer, there is a resistance layer between the resistance layer and the insulating coating layer. 1. A partial voltage resistance element for incorporating an electron tube, characterized in that a barrier layer is provided, and the barrier layer is a metal oxide layer formed by hydrolysis of an organometallic compound layer containing a metal alkoxide.