JPH0316728B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cathode holding hermetic component for an electron gun, and particularly to a contact interface structure of a metal member that makes surface contact with a glass substrate.

FIGS. 1A and 1B are a plan view and a sectional view taken along the line A-A', respectively, showing an example of a conventionally proposed cathode holding hermetic component for an electron gun. In these figures, the cathode holding hermetic part 1
consists of a glass substrate 2 made of crystallized glass, a cylindrical body 3 made of a conductor surrounding the side surface of this glass substrate 2, and a cylindrical conductor penetrating through this glass substrate 2 and arranged in-line and sealed. Multiple cathode supports (hereinafter referred to as eyelets) 4
A cathode (not shown) is inserted into each of these eyelets 4 and held fixed thereto. This cathode holding hermetic component 1 is arranged in a predetermined positional relationship with a first grid electrode (not shown).

In order to manufacture the cathode holding hermetic component 1 constructed in this manner, the cylindrical body 3 and the eyelets are generally placed in a firing jig made of carbon material, taking into consideration heat resistance and the prevention of glass adhesion. 4 and a glass substrate 2, a cylindrical body 3, and an eyelet 4 loaded with preformed or calcined pellet-like or powdered crystallized glass and fired at approximately 750°C to 850°C in an N ₂ atmosphere. A cathode holding hermetic component 1 is formed.

However, in the cathode holding hermetic component having the above configuration, as shown in the enlarged cross-sectional view of the main part in FIG.
Wetting up parts 2a, 2b of the glass substrate 2 were generated between the adhesive interfaces 3a, 4a and the surface of the glass substrate 2. And these wet rising parts 2a, 2b
The occurrence of this is an extremely undesirable phenomenon for a cathode holding hermetic component of an electron gun for an electron tube. That is, the cathode holding hermetic part 1
When forming the carbon jig with a firing jig made of carbon material, if the wetting up parts 2a and 2b occur, the cathode holding hermetic part 1 and the carbon jig are tightly engaged, making it extremely difficult to remove the carbon jig, which makes the work difficult. This resulted in poor performance and decreased yield. Furthermore, when assembling the electron gun, a cathode, an electrode fixing frame, etc. (not shown) are welded and fixed to the cylindrical body 3 and the eyelet 4, but at this time the cylindrical body 3 and the eyelet 4 are fixed to the cylindrical body 3 and the eyelet 4 as shown in FIG. B-
Stress is applied in the B′ direction. In addition, the product may be subjected to rapid heating and cooling for aging purposes. At such times, the glass in the wetted areas 2a and 2b sometimes peeled off and fell off. This fallen glass clogs the holes in the shadow mask of the picture tube and causes trace sparks, leading to various malfunctions. On the other hand, since these cylindrical bodies 3 and eyelets 4 are welded, they cannot be oxidized, and therefore have the drawback that the adhesive force at the adhesive interfaces 3a, 4a with the glass substrate 2 is extremely weak.

Therefore, the present invention provides an electron gun that prevents wetting of the glass substrate by providing uneven portions on the adhesive interface between the glass substrate, the cylindrical body, and the eyelet, and further improves the adhesive strength between the two. The purpose is to provide a cathode retention hermetic component.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 3 is an enlarged cross-sectional view of a main part for explaining an example of the cathode holding hermetic component for an electron gun according to the present invention, and since the same symbols as in the previous figure represent the same elements, the explanation thereof will be omitted. In FIG. 3, the adhesive interface 3a between the cylindrical body 3 and the glass substrate 2 and the adhesive interface 4a between the eyelet 4 and the glass substrate 2 are formed with fine irregularities by, for example, mechanical scratching, sandblasting, or chemical treatment. Part 3
b and 4b are formed, respectively.

According to such a configuration, by forming the uneven portions 3b and 4b on the adhesive interfaces 3a and 4a of the cylindrical body 3 and the eyelet 4, respectively, wetting of the glass substrate 2 becomes poor, and therefore the second Since wetting up parts 2a and 2b as shown in the figure are hardly generated, it is possible to prevent the glass from peeling off and falling off. Furthermore, since the glass substrate 2 uses semi-crystalline glass to improve heat resistance, if the adhesive interfaces 3a and 4a of the cylindrical body 3 and the eyelet 4 have uneven portions 3b and 4b, the progress of crystallization may occur. was extremely stable, the strength of the glass at the adhesive interfaces 3a and 4a was improved, and the adhesive strength was able to be significantly improved. Furthermore, the semi-crystalline glass material penetrated into the uneven portions 3b and 4b, increasing the bonding surface area and improving mechanical holding power, thereby making it possible to further increase the bonding strength.

A more detailed explanation will be given below using specific examples.

First, as the cylindrical body 3 shown in FIG.
The adhesive interface 3a using the alloy and the adhesive interface 4a using the Fe-Ni-Co alloy as the eyelet 4 were each sandblasted for about 5 minutes using a #100 carborundum abrasive. After thoroughly washing the sandblasted cylindrical body 3 and eyelets 4,
Foreign matter treatment on the surface was carried out in a hydrogen stream. Next, ZnO-- _{B2O3 - SiO2} -MgO semicrystalline glass was used as the glass substrate 2, and a glass button was formed by press molding and pre-baking. and,
The cylindrical body 3, the eyelet 4, and the above-mentioned glass button were each packed into a carbon jig (not shown) at predetermined positions, and main firing was performed at about 800°C to produce a cathode holding hermetic part. As a result of examining the height of the wetted parts 2a and 2b of the cathode holding hermetic part manufactured in this way, it was found that it was approximately 0.1 mm.
It was below. Furthermore, this product was incorporated into a color picture tube and the failure rate due to shadow mask clogging due to falling glass pieces during each process was investigated, and the result was 0%. In addition, the manufactured cathode holding hermetic part was attached to a pressure loading device called Tensilon, which consists of a pedestal 5 shown in FIG. 4, a pressure jig 6, and a pressure gauge 7, and pressure was applied to the glass. As a result of measuring the strength with which the substrate 2 falls off, it was found that it can withstand approximately 110 kg/cm ² or more.
On the other hand, uneven portions 3 are formed on the adhesive interfaces 3a and 4a of the cylindrical body 3 and the eyelet 4 with the glass substrate 2.
The cathode holding hermetic parts manufactured using the same materials and the same processes as those in the above embodiments, except that b and 4b were not applied, were as follows:
The dimensions of a and 2b were large, 1.0 to 2.0 mm, and the defective rate due to shadow mask clogging was about 0.2%. Also,
The strength of this component in the drop-off test of the glass substrate 2 was extremely weak at 70 to 80 kg/cm ² .

In another embodiment, the uneven parts 3b and 4b of the adhesive interfaces 3a and 4a of the cylindrical body 3 and the eyelet 4 with the glass substrate 2 are formed by mechanically scratching them using a lurette instead of sandblasting. Except for the attachment method, the cathode holding hermetic part was manufactured using the same materials and the same process as in the above example. The height of the wetted parts 2a and 2b of this part is approximately 0.15 mm, there is no falling glass piece, and the defect rate due to shadow mask clogging is 0.
It was %. Further, the strength of the glass substrate 2 in the drop-off test shown in FIG. 4 was extremely high, approximately 100 kg/cm ² or more.

As explained above, according to the present invention, since no wetted portion of the glass substrate occurs, falling glass pieces are eliminated, and the occurrence of defects due to clogging of the shadow mask of the picture tube is reduced from about 0.2% in the conventional case to 0%. The amount of damage was drastically reduced and reliability was greatly improved. Also,
Since there is no wetted part, there is no strong engagement with the carbon jig, and the carbon jig can be easily removed, improving yield by about 10%. Furthermore, the adhesive strength between the glass substrate, the cylindrical body, and the eyelet is greatly improved, and various excellent effects can be obtained, such as the ability to significantly improve the reliability of life.

[Brief explanation of the drawing]

Figures 1a and 1b are plan views showing an example of a conventional cathode holding hermetic part for an electron gun;
2 is an enlarged sectional view of the main part of a conventional cathode holding hermetic component for an electron gun, and FIG. 3 is an enlarged sectional view of the main part showing an example of the cathode holding hermetic component for an electron gun according to the present invention. FIG. 4 is a sectional view of a main part of a pressure loading device for explaining a test method for a cathode holding hermetic component for an electron gun. 1... Cathode holding hermetic parts, 2...
Glass substrate, 2a, 2b... Wet rising part, 3...
Cylindrical body, 3a... adhesive interface, 3b... uneven portion, 4
...Cathode support (eyelet), 4a...
Adhesive interface, 4b... uneven portion.

Claims (1)

[Claims] 1. A cathode holding hermetic component for an electron gun comprising a glass substrate, a cylindrical body surrounding a side peripheral surface of the glass substrate, and a cathode support implanted through the glass substrate, which is in contact with the glass substrate. A cathode holding hermetic component for an electron gun, characterized in that an uneven portion is provided on an adhesive interface of at least one of the cylindrical body and the cathode support.