JPH02148644A - Manufacture of cathode-ray tube - Google Patents

Abstract

PURPOSE:To make a getter stable to the exposure to the air for a long time and obtain a highly reliable cathode ray tube by completely sealing a getter material received in a metal ring vessel for getter of cathode ray tube by a metal foil. CONSTITUTION:A sealed type getter 12 mounted to the inside of a cathode ray tube with the opening part of a metal ring vessel 13 being completely covered with an aluminium metal foil 18 is heated by a high frequency coil outside from a vacuum envelop of the cathode ray tube after the process of exhausting the inside of the cathode ray tube into vacuum. At this time, the aluminium metal foil 18 is preferably first evaporated as its lower melting point than a getter material 14 to form an opening, followed by evaporation of the getter material 14. Thus, in the sealed type getter, the deformation of the getter material 14 by its adsorption of moisture in the air is never caused, even if time is passed after the installation of the getter to an electron gun 19.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a method for manufacturing a cathode ray tube with improved getter action.

[Conventional technology]

A shadow mask type color cathode ray tube, which is currently in widespread use, will be explained with reference to FIG.

In the figure, (1) is a color cathode ray tube made of glass, with a panel (2), a funnel (3) and a neck part (4).
) constitutes a vacuum envelope. The inner surface of the panel (2) has a shadow mask (
6) is fixed in place and this shadow mask (6)
After forming a fluorescent surface (not shown) on the inner surface of the panel using a pattern of many round holes (or square holes) provided in the panel (2), an internal magnetic shield (7), etc. is installed.
) is joined by the funnel (3) and the frit glass (8). At this time, in order to melt and crystallize the frit glass, the pair of panel (2) and funnel (3) with paste of frit glass (8) sandwiched between them is subjected to high temperature treatment at approximately 440°C in air. Bonding using the frit glass (8) is completed. After this, the electron gun (9) is inserted into the fixed position inside the neck part (4), and the stem glass Ql to which the electron gun (9) is fixed and the neck part (4) are melted and sealed with a burner. After that, panel (2), funnel (3)
), the vacuum envelope consisting of the neck part (4) is heated to approximately 400'O
While heating at a high temperature, the air inside is evacuated through the hole of a glass chip tube (not shown) attached to the stem glass A1 to create a high vacuum, and the chip tube is heated and melted to seal it. The evacuation of the cut color cathode ray tube is completed. The higher the vacuum opening in the vacuum surrounding atmosphere of the color cathode ray tube (1), the better for the life of the color cathode ray tube. Therefore, as shown in FIG. 2, a getter (6) is usually attached to the tip of the electron gun (9) via a spring αυ. This getter (6) has a structure as shown in Fig. 3, and a getter material α4 mainly made of barium (Ba) is housed inside a gold 1m IJ ring 8n03 with an opening on one side. ing. After the evacuation of the inside of the color cathode ray tube (1) is completed, as shown in Fig. 2, the metal ring container (
) is heated to a high temperature, and a getter material mainly made of barium (Ba) is vacuum evaporated inside the color cathode ray tube, and the residual gas molecules remaining inside the color cathode ray tube after exhaust are adsorbed on this evaporation surface to form the color. It becomes possible to greatly increase the degree of vacuum inside the cathode ray tube. Figure 4 shows a cross-sectional view of the getter (6), and one support Q0 is made by floating the metal ring container α1 of the getter (A) from the inner surface of the funnel (3). To prevent heat generation from a ring container (toward) from being transmitted to funnel glass as much as possible.

[Problem to be solved by the invention]

Such conventional color cathode ray tube getters have had several major problems. The first problem is that if the getter material is left exposed to air for too long, it will absorb moisture and the getter function will be impaired. However, it was necessary to evacuate the inside, which was a major constraint on the manufacturing process of color cathode ray tubes. Furthermore, fixing the getter to the tip of the electron gun via a spring puts extra force on the electron gun body, which has a negative effect on the sealing accuracy of the electron gun. Recently, a nipple pin for fixing the getter has been installed inside the funnel at a position as far away from the neck as possible, as shown in Figure 5, to prevent it from adversely affecting the magnetic field of the deflection yoke located near the joint of the getter. The getter is fixed after being separated from the electron gun. The major problem with this method is that the getter must be fixed inside the funnel before the panel and funnel are joined with the frit glass, and the getter is exposed to the heat treatment process of melting and crystallizing the frit glass described above. This will significantly impair the performance of the getter for the same reason as mentioned above. In addition, when separating the getter from the electron gun, it is possible to consider not only the method of attaching it to the inner surface of the funnel, but also a method of fixing it to the 7 frame holding the shadow mask, a method of fixing it to the internal magnetic shield, etc. . Furthermore, in the case of these methods, it is relatively easy to install a large number of getters inside the color cathode ray tube.

This invention was made to solve the above-mentioned problems, and it not only does not cause any problem in the stability of the getter action even if the getter is attached to the electron gun and time passes, The object of the present invention is to obtain a method for manufacturing a cathode ray tube that does not cause any problems in the stability of the getter action even in the manufacture of color cathode ray tubes in which the getter is separated from the electron gun. In the method for manufacturing a cathode ray tube according to the invention, the opening of a metal ring container having a getter material inside is made of aluminum (AL).
) etc. is used, and when the getter material is evaporated by means such as high-frequency heating, the sealing metal foil is also evaporated at the same time.

[Effect]

In the method for manufacturing a cathode ray tube according to the present invention, the getter material housed in the metal ring container is completely sealed with metal foil, so even if it is exposed to air for a long time, the getter material is not affected at all. Further, since the metal foil for sealing is made of a low melting point substance such as aluminum (AL), it is evaporated almost simultaneously with the getter by high frequency heating similar to the conventional getter evaporation.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. In the method for manufacturing a cathode ray tube according to the present invention, the structure of the getter υ is different from the conventional one. The getter material A4 is housed inside the metal ring container (to), which is exactly the same as before, but the opening of the metal ring container (to) is completely closed by the aluminum (kL) metal foil (to). The covered getter material 04 is sealed. This kind of sealed getter is made by packing aluminum (
Most preferably, this is done by completely sealing the opening of the metal ring container (to) with a metal foil (to) of AL). With such a sealed getter, even if time passes after the getter (B) is attached to the electron gun (9), the getter material α
→ will never change in quality due to adsorption of moisture etc. in the air.

For the same reason, no problem will occur if the getter (6) is previously attached to the inside of the funnel (3) before joining the panel (2) and the funnel (3), and then the heat treatment process for joining is performed. The hermetically sealed getter thus installed inside the cathode ray tube is heated by a high frequency coil from outside the vacuum envelope of the cathode ray tube after the process of evacuating the inside of the cathode ray tube. At this time, the aluminum (AL) metal foil (T) evaporates first as the getter material Q has a low melting point, and after the opening of the metal ring container (K) is formed, the getter material α→ evaporates. Very preferred. Therefore, as the material for the metal foil, a material should be selected that has a melting point at least equal to or lower than that of the getter material a. Code a! ◆ indicates a spring when attaching the getter (2) to the electron gun (9), but indicates a support plate for fixing when detaching it from the electron gun (9) and attaching it to the nipple bin QQ etc. on the inner surface of the funnel (3). .

Further, in the above embodiments, the method for manufacturing a color cathode ray tube was mainly explained, but the present invention is not limited to this, and the same can be applied to a method for manufacturing a wide range of general cathode ray tubes such as a monochrome gap tube. It is possible to obtain the effect.

〔Effect of the invention〕

As described above, according to the present invention, the getter material housed in the metal ring container of the getter of the cathode ray tube is completely sealed with metal foil, so it is extremely stable even if the getter is exposed to the air for a long time. 9. To provide a method for manufacturing cathode ray tubes that is not only extremely reliable but also allows for easy separation of the getter from the electron gun. is also possible.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a sealed getter used in the method of manufacturing a cathode ray tube according to the present invention, FIG. 2 is a sectional view of a conventional color cathode ray tube, FIG. 3 is a schematic diagram of a conventional getter, and FIG. FIG. 3 is a sectional view, and FIG. 6 is a sectional view of a color cathode ray tube in which a getter is attached to the inner surface of the funnel. In the figure, (1) is a color cathode ray tube, (2) is a getter, (
) is metal foil. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Fig. 1 12 pieces / 13 1A / 1 / 8: metal 5 Fig. 2

Claims (1)

[Claims] (1) A getter material is stored inside a metal ring container with an open end, and the opening of the metal ring container is completely sealed with metal foil having a lower melting point than the getter material. After the cathode ray tube is installed in a fixed position, the sealing metal foil and getter material of the hermetic getter are removed from the outside of the cathode ray tube vacuum envelope in the process of evacuating the inside of the cathode ray tube or sealing the vacuum surrounding air. A method for manufacturing a cathode ray tube characterized by heating and evaporating it using a heating means such as high frequency heating.