JPH0828186B2 - Color picture tube manufacturing method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas discharge treatment for heating a screen film material attached to the inner surface of a face panel member to remove organic substances and water contained in the material. The present invention relates to a method for manufacturing a color picture tube, which is performed during a hot sealing process between a member and a funnel member.

2. Description of the Related Art Generally, in the manufacture of a color picture tube, a screen film material composed of a light absorbing film, a phosphor film lacquer film and a metal back film is attached to the inner surface of a face panel member made of glass, and then heated to a high temperature in air. By heating, the organic substances and water in the screen film material are removed. Then, the face panel member having the screen film that is outgassed in this manner is abutted against the funnel member that forms a valve together with the member through the frit glass layer, and the frit glass layer is heated and melted in the air. By doing so, both are hot-sealed.

Further, in order to reduce the manufacturing cost of the color picture tube, it is also known to perform the above-mentioned gas discharge treatment during the hot sealing treatment process of the face panel member and the funnel member. However, according to the latter method of the related art, the air in the valve is liable to lack oxygen during the heat treatment, the organic substances in the screen film material cannot be completely burned and removed, and the frit glass layer is deteriorated to cause sealing. The result is that the withstand voltage characteristic of the part is deteriorated.

Therefore, it has been attempted to intermittently send the oxygen-containing gas into the valve through the neck portion of the funnel member during the temperature rising period during the hot sealing treatment process, but an efficient heat treatment cannot be expected. Moreover, when the intermittent supply amount of the oxygen-containing gas is increased, a turbulent flow is generated in the neck portion and the gas replaceability is impaired. Moreover, as a result of the internal pressure of the valve becoming higher than the external pressure of the valve, the frit glass being melted is pushed out of the valve, and it becomes difficult to obtain a good airtight sealing effect. Furthermore, it takes a considerable amount of time to completely burn and remove the organic substances in the screen film material, so this cannot be completed during the temperature rise period,
If the gas inside the valve is not replaced even after that,
Carbon dioxide and water vapor generated by firing remain in the bulb and are adsorbed on the metal back film, the light absorbing film, and the like.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention Therefore, it is an object of the present invention to efficiently perform the gas discharge treatment of the screen film material during the hot sealing treatment step without causing the above-mentioned troubles. Another object is to provide a mass-produced color picture tube manufacturing method.

Means for Solving Problems A method of manufacturing a color picture tube according to the present invention comprises a face panel member having an inner surface provided with a screen film material, a funnel member forming a valve together with the same, via a frit glass layer. Butt, and the valve in this butted state is transferred to a heating furnace by a transfer means having a thin tube having one end inserted in the neck portion of the funnel member of the valve, and is sequentially subjected to steps of temperature rise, high temperature hold and temperature drop. Outgassing the screen membrane material, and
When the frit glass layer is melted and the face panel member and the funnel member are sealed, a movable pipe of a gas supply device which is provided outside the heating furnace and interlocks with the transfer means in the heating furnace. , Is joined to the other end of the thin tube through an opening provided in the heating furnace wall, and oxygen-containing gas is not supplied from the gas supply device in the latter half period of the high temperature holding step in the latter half period of the temperature increasing step. After supplying active gas or hot air into the valve, respectively, the movable pipe is separated from the other end of the thin tube to return to the original position, and the movable pipe is connected to the other end of the thin tube of the subsequent transfer means. After joining, the oxygen-containing gas and the inert gas or the hot air are supplied to the valve again.

Function With this configuration, the gas in the valve is well replaced, and the gas or hot air is supplied to the valve.
It becomes possible to perform smoothly and continuously without generating turbulence in the neck portion, the organic substance in the screen film material can be completely burned and removed, and the above-mentioned conventional inconvenience can be eliminated.

EXAMPLE In FIG. 1 showing one example of the present invention, a glass face panel member 1 is provided with a screen film material 2 as described above on its inner surface, and a funnel member 3 has a large diameter opening end face. Are abutted to each other via the frit glass layer 4. A metal detail tube 6 is inserted through the neck portion 5 of the funnel member 3, and the position occupied by the upper end portion of the thin tube 6 reaches the conical portion 7 beyond the area of the neck portion 5, and the flare lower end. The portion 8 is provided with an appropriate number of springs 9 protruding in a hairpin shape. The thin tube 6 is coaxially supported in the neck portion 5 by the spring 9 engaging with the flared opening edge of the neck portion 5, and the gap between the inner peripheral surface of the neck portion 5 and the thin tube 6 is gas. It becomes the discharge path 10. Further, the tip of the gas supply nozzle 11 is inserted into the flaky lower end 8 of the thin tube 6. However, the thin tube 6 is attached to the funnel member 3 before the face panel member 1 is butted. The inner diameter phi of the capillary 6 is set so that the internal cross-sectional area of the capillary 6 (φ / ²⁾ 2 π is 40% to 60% of the cross-sectional area of the gas discharge passage 10.

This structure is set on a rack 12 which is a transfer means as shown in FIG. 2, and is slowly transferred together with the rack 12 in the heating furnace in the direction of an arrow 13 to raise the temperature as shown in FIG. Then, the steps of maintaining a high temperature and lowering the temperature are sequentially performed. However, the gas supply nozzle 11 communicates with the joint portion 15 via the pipe 14, and the tip of the movable pipe extending from the gas supply device is joined to the joint portion 15 for a predetermined time. That is, as shown in FIG.
When 15 moves along the laterally long opening 17 of the side wall of the heating furnace 16, the tip of the movable pipe 19 extending from the gas supply device 18 is joined to the joint 15 for a predetermined time, and during this joining period. The required amount of gas is continuously fed. The pipe 19 during the gas supply period moves together with the rack 12, but stops after a predetermined time elapses, retracts to the gas supply device 18 side, and returns to the original position. Then, the operation of joining to the joining portion of the subsequent rack that is transferred next for a predetermined time and starting the gas supply again is repeated.

A transfer belt made of a metal net is laid in the heating furnace 16, hot air from a heating chamber provided with an electric heater is fed from below the belt, and the hot air is circulated in the furnace by a fan. It is like this.

The gas supplied from the gas supply device 18 is an oxygen-containing gas, and is continuously sent in an amount required for combustion of the organic substances contained in the screen film material 2. Since the organic substance has the temperature-burnup characteristics as shown in FIG. 4, the gas supply in the temperature increasing step is performed in the latter half period A as shown in FIG. This period A is also a period in which the coating film of the frit glass layer 4 dissolves, and it is preferable to use dry air having a dew point of 0 ° C. or lower as the oxygen-containing gas.

As shown in FIG. 6, since it takes 40 minutes or more to complete the combustion of the organic substance (heating temperature 450 ° C.), the combustion is performed even after the temperature rising period of 35 minutes in the hot sealing process has elapsed. Need to continue. Therefore, a part of the combustion gas remains in the valve, and in order to prevent the residual gas from being adsorbed by the screen film material 2 during the cooling period, the gas is supplied again in the latter half period B of the high temperature holding step. , Exhaust all combustion gas in the valve to the outside of the valve. The gas supplied during the period B is preferably an inert gas, especially a nitrogen gas, but may be dry air having a dew point of 0 ° C. or lower, that is, hot air.

EFFECTS OF THE INVENTION Since the present invention is configured as described above, generation of turbulent flow particularly in the neck portion is eliminated, gas in the valve is efficiently replaced, and gas treatment and hot sealing of the screen film material are performed. The treatment and the treatment can be efficiently achieved at the same time. Further, gas can be supplied to the thin tubes of the subsequent transfer means by one movable pipe, the color picture tube can be continuously manufactured, the mass productivity is excellent, and the gas supply device for each transfer means can be eliminated. Moreover, since the opening provided on the wall of the heating furnace can be made small, it becomes easy to manage the gas temperature, the gas supply amount, etc. of the gas supply device, and it is possible to manufacture a color picture tube of stable quality and improved quality. Since the gas supply device can be dispensed with for each time and the gas supply amount is supplied only for a predetermined period, a color picture tube excellent in economical efficiency can be manufactured.

[Brief description of drawings]

FIG. 1 is a side sectional view of an essential part of one embodiment of the present invention, FIG. 2 is a perspective view of a rack in the same embodiment, and FIG. 3 is a perspective view showing the relationship between a heating furnace and a gas supply device. 4 to 6 are various characteristic diagrams. 1 ... face panel member, 2 ... screen film material,
3 ... Funnel member, 4 ... Frit glass layer, 5 ...
… Neck part, 6… narrow tube.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Keiichi Tanabe 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electronics Industry Co., Ltd. (72) Shoichi Maeda, 1006 Kadoma, Kadoma City, Osaka Matsushita Electronics Industry Co., Ltd. (56) References JP-A-53-31957 (JP, A)

Claims (1)

[Claims] 1. A face panel member having an inner surface provided with a screen film material is abutted with a funnel member forming a valve together with the same through a frit glass layer, and the abutted valve is the funnel of the valve. The material is transferred into a heating furnace by a transfer means having a thin tube having one end inserted in the neck portion of the member, and is sequentially subjected to steps of temperature increase, high temperature holding, and temperature decrease, and gas treatment of the screen film material, and the frit. When melting the glass layer to seal the face panel member and the funnel member, the movable pipe of the gas supply device which is provided outside the heating furnace and is interlocked with the transfer means in the heating furnace, Joined to the other end of the thin tube through an opening provided in the heating furnace wall, and from the gas supply device to the second half period of the temperature increasing step. Oxygen-containing gas, inert gas or hot air in the latter half of the high temperature holding step, after each is supplied into the valve, the movable pipe is separated from the other end of the thin tube to return to the original position, A method for manufacturing a color picture tube, characterized in that the movable pipe is joined to the other end of the thin tube of the subsequent transfer means to supply the oxygen-containing gas and the inert gas or the hot air to the valve again. .