JPH08287830A - Flat fluorescent lamp and its manufacture - Google Patents

Abstract

PURPOSE: To hold a necessary enough quantity of mercury in a discharge chamber, and attain qualitative stability and an improvement in brightness of a fluorescent lamp by arranging the specific constitution in a prescribed manufacturing method of a flat fluorescent lamp. CONSTITUTION: A flat fluorescent lamp 10 is constituted in such a way that two glass plates 2 on which light emitting layers composed of an electrode layer 3, a dielectric layer 4 and a phosphor layer 5 are respectively arranged are opposed to each other with proper intervals on the light emitting layer side, and a sealing process is performed on the peripheral edge by a sealing frame 6 by low melting point glass, and a discharge chamber 10a is formed, and noble gas and mercury are sealed in the discharge chamber 10a. In a manufacturing method of this lamp, a notch part is arranged in one place in the sealing frame 6 to be used in the sealing process, and a sealing port 10b is provided to communicate the discharge chamber 10a and outside air with each other by the notch part, and an empty cell 10 is formed. After air is exhausted and noble gas is sealed in and mercury 7 is sealed in this empty cell 10 through the sealing port 10b, the sealing process by a sealing member 11 of the sealing port 10b is performed by partial heating (a heater 22) in the vicinity of the sealing port 10b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent lamp, and more particularly, to a fluorescent lamp of a flat type suitable as a backlight light source of a liquid crystal display used as a display unit of a portable computer. It is a thing.

[0002]

2. Description of the Related Art As a conventional method of manufacturing a flat fluorescent lamp 90 of this type, Japanese Patent Laid-Open No. 6-1766 by the same applicant.
No. 93 (Japanese Patent Application No. 4-351733), there is an electrode layer 92a, as shown in FIG.
The two glass substrates 91 on which the dielectric layer 92b and the phosphor layer 92c are sequentially stacked are provided in the phosphor layer 92c.
The inside is on the side of and the seal frame 93 is disposed between both substrates, and they are faced to each other in the chamber 80 at appropriate intervals.

In this state, exhaust in the chamber 80,
A rare gas is injected and heated by the heater 81 while maintaining the atmosphere, and then one of the glass substrates 91 is moved to sandwich the seal frame 93 as shown in FIG. The periphery of the glass substrate 91 of
The flat fluorescent lamp 90 is manufactured by sealing with 3 and forming a discharge chamber 90a between two glass substrates 91.

A mercury amalgam 94 is placed on a part of the phosphor layer 92c of one of the glass substrates 91, and mercury is sealed in the sealing step at the same time. Further, in actual production, a plurality of glass substrates 91 are taken and are cut after the sealing step to be separated into individual flat fluorescent lamps 90.

[0005]

However, in the above-mentioned conventional manufacturing method, when the two glass substrates 91 and the seal frame 93 are welded together, all of them have the seal frame 93 formed therein. Since the melting point glass is heated to the softening temperature (for example, 450 ° C.), the mercury amalgam 94 placed on the phosphor layer 92 also releases mercury vapor and diffuses into the chamber 80, and after sealing is performed. There is a problem that the amount of mercury in the flat fluorescent lamp 90 is insufficient.

The above is a problem that can be solved by increasing the area of the mercury amalgam 94, but on the other hand, since the phosphor layer 92 in the portion where the mercury amalgam 94 is placed becomes a non-light emitting portion, uneven illumination occurs. In order to prevent this, the area of the mercury amalgam 94 is required to be as narrow as possible, and it is impossible to further expand the area. Therefore, there is no means for eliminating the shortage of mercury. However, the solution to this point has become an issue.

[0007]

As a concrete means for solving the above-mentioned conventional problems, the present invention provides two light-emitting layers each including an electrode layer, a dielectric layer, and a phosphor layer. The glass substrate of is opposed to the light emitting layer at an appropriate interval and the periphery is sealed by a sealing frame made of low melting point glass to form a discharge chamber, and a discharge gas is formed in the discharge chamber. In the method for manufacturing a flat fluorescent lamp described above, an empty cell having a notch portion provided at one position in the sealing frame used in the sealing step and having a sealing port that allows the discharge chamber and the outside air to communicate with each other in advance is provided. Shall be formed,
Exhausting into the empty cell through the filling port, filling rare gas,
To provide a method for manufacturing a flat fluorescent lamp, characterized in that, after the sealing of mercury is performed, a sealing step of the sealing port with a sealing member is performed by partial heating in the vicinity of the sealing port. The object is to solve the problem by enclosing a necessary and sufficient amount of mercury inside.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail based on an embodiment shown in the drawings. In manufacturing the flat fluorescent lamp 1 according to the present invention, first, an empty cell 10 shown in FIGS.
To form. As described in the conventional example, this empty cell 10 has two glass substrates 2 each having an electrode layer 3, a dielectric layer 4, and a phosphor layer 5 formed therein, and the phosphor layer 5 is inside. And a peripheral edge thereof is joined by a seal frame 6 made of low melting point glass (frit glass).

Here, in the present invention, the notch 6a is provided at one place of the seal frame 6, whereby the discharge chamber 10a is formed between the two glass substrates 2. The discharge chamber 10a has a sealing port 10b communicating with the outside air at the above-mentioned cutout portion.

Therefore, in the step of forming the empty cell 10, no exhaust gas, noble gas, or mercury filling is performed. Therefore, the glass substrate 2 and the seal frame 6 may be welded in an atmosphere that does not cause oxidation of the electrode layer 3 such as in nitrogen gas or hydrogen gas.

In the present invention, the empty cell 10 is formed as described above, and the sealing member 11 for closing the sealing port 10b is formed, and the sealing member 11 is the glass substrate 2 The same material used to form the
As shown in FIG. 5, the empty cell 10 is formed in a substantially U-shape across the thickness direction, and a bonding layer 11a made of the same material as the seal frame 6 is provided at a portion in contact with the empty cell 10.

At this time, the bonding layer 11a may be provided on the sealing member 11 side as described above, but may be provided on the peripheral edge of the filling port 10b on the empty cell 10 side. Further, it may be provided on both the sealing member 11 side and the empty cell 10 side. In addition, the bonding layer 11a may be omitted by forming the entire sealing member 11 with the same material as the sealing frame 6.

As shown in FIG. 4, the empty cell 10 and the sealing member 11 formed as described above are exhausted in the chamber 20, injected with a rare gas, injected with mercury 7, and sealed the inlet 10b. Thus, the flat fluorescent lamp 1 is obtained. At this time, the empty cell 10 is set in the chamber 20 with the side provided with the sealing port 10b as an upper side, and the empty cell 10 is closed on the side provided with the sealing port 10b and the sealing port 10b. The sealing member 11 is laid across the unmarked position.

In this state, the chamber 20 is evacuated, and then the rare gas and the mercury 7 are injected. If the rare gas is injected into the chamber 20 after being exhausted so as to have a predetermined concentration, the discharge chamber 10a in the empty cell 10 has the same condition, but the dispenser 21 for mercury 7 is used. Thus, a prescribed amount of mercury 7 is dropped and injected directly into the empty cell 10. At this time, the chamber 20
If the inside is kept at approximately room temperature, the mercury 7 will remain in a liquid state.

After the mercury 7 is injected, the sealing member 11 is slid to a position where the sealing port 10b is covered, as shown in FIG.
When the heater 22 is brought into close contact with the sealing member 11 and heated (for example, 500 ° C.) as shown in FIG. 5, the bonding layer 11a is melted and the sealing port 10b is sealed, and the flat fluorescent lamp 1 is completed. Incidentally, unnecessary parts such as legs when the sealing member 11 has a substantially U shape may be removed after being taken out from the chamber 20.

Further, when the entire sealing member 11 is made of low melting point glass, the heater 22 does not necessarily have to be in close contact with the sealing member 11, and a gap may be provided between them to be welded by radiant heat. It is also possible, and further speaking, the sealing can be performed by dropping the melted low melting point glass toward the sealing port 10b without forming the sealing member 11.

Next, the operation and effect of the flat fluorescent lamp 1 having the above structure and manufacturing method will be described. According to the present invention, an empty cell 10 having a filling port 10b is formed in advance, and a rare gas and mercury 7 are injected into this empty cell 10,
Since the sealing port 10b is sealed by the sealing member 11, firstly, the mercury 7 is injected in the highest temperature step of welding the two glass substrates 2 and the seal frame 6 together. It is assumed that the mercury 7 does not dissipate due to evaporation, and the required amount is reliably retained in the discharge chamber 10a.

Secondly, when the empty cell 10 is sealed, partial heating of the sealing member 11 is sufficient so that the whole is not heated, and evaporation does not occur even in the state of mercury 7. By doing so, it is not necessary to use mercury amalgam in the conventional example, and thereby it is also possible to prevent the phosphor layer 5 from being covered with the mercury amalgam and becoming a non-light emitting portion.

[0019]

As described above, according to the present invention, the seal frame used in the sealing step is provided with a notch at one location and has a pre-filled space through which the discharge chamber communicates with the outside air. A cell is to be formed, and after the empty cell is evacuated, the rare gas is filled, and the mercury is filled through the filling port, the sealing process by the sealing member of the filling port is performed near the filling port. By adopting a method for manufacturing a flat fluorescent lamp that is performed by heating, firstly, sealing can be performed by welding a sealing member with a small heating amount, so that the dissipation due to evaporation of mercury is eliminated and the discharge chamber As it holds a necessary and sufficient amount of mercury, it has an extremely excellent effect in improving the performance of the flat fluorescent lamp, such as stabilizing the quality and improving the brightness.

Secondly, since the amount of heat applied at the time of sealing is small as described above, it is not necessary to use the conventionally used mercury amalgam, which allows the phosphor layer to be formed by the mercury amalgam. It is also possible to prevent that portion from becoming a non-light emitting portion by being covered, and to uniformly emit light over the entire surface so that uneven brightness does not occur, and in this respect also, an excellent effect of improving the performance of the flat fluorescent lamp is exhibited.

[Brief description of drawings]

FIG. 1 is a perspective view showing a state of forming empty cells in a method of manufacturing a flat fluorescent lamp according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a cross-sectional view showing a state of formation of a sealing member of the same embodiment.

FIG. 4 is an explanatory diagram similarly showing a state of a process of performing exhaust, rare gas injection, and mercury injection and sealing of a sealing port.

FIG. 5 is likewise a sectional view showing a step of welding an empty cell and a sealing member.

FIG. 6 is an explanatory diagram showing a conventional exhaust process and a rare gas injection process.

FIG. 7 is an explanatory diagram showing a sealing process of a conventional example.

[Explanation of symbols]

 1 ... Flat fluorescent lamp 2 ... Glass substrate 3 ... Electrode layer 4 ... Dielectric layer 5 ... Phosphor layer 6 ... Seal frame 7 ... Mercury 10 ... Empty cell 10a ... Discharge chamber 10b ... Filling port 11 ... Sealing member 11a ... Bonding layer 20 ... Chamber 21 ... Dispenser 22 ... Heater

Claims (6)

[Claims] 1. A pair of glass substrates, each provided with a light emitting layer composed of an electrode layer, a dielectric layer, and a phosphor layer, are opposed to each other at appropriate intervals on the side of the light emitting layer, and their edges are made of low melting point glass. In a method of manufacturing a flat fluorescent lamp in which a sealing step is performed by a sealing frame to form a discharge chamber, and a rare gas and mercury are sealed in the discharge chamber, the sealing frame used in the sealing step includes A notch is provided at one location to form an empty cell having a filling port that allows the discharge chamber and the outside air to communicate with each other in advance, and the empty cell is exhausted through the filling port, a rare gas is filled, and mercury is filled. After the inclusion of
A method for manufacturing a flat fluorescent lamp, wherein the step of sealing the sealing port with a sealing member is performed by partial heating in the vicinity of the sealing port. 2. The sealing member is made of the same material as the glass substrate, and at least one of a surface of the sealing member on the side of the sealing port and a peripheral edge of the sealing port is made of the same material as the sealing frame. 2. The method for manufacturing a flat fluorescent lamp according to claim 1, wherein the bonding layer is provided, and the sealing step is performed by heating the sealing member. 3. The method of manufacturing a flat fluorescent lamp according to claim 1, wherein the sealing member is made of the same material as the sealing frame, and the sealing step is performed by heating with radiant heat. 4. The sealing member is made of the same material as the sealing frame, and the sealing step is performed by melting and dropping the sealing member into the sealing port. Method of manufacturing flat fluorescent lamp. 5. The sealing member is formed in a substantially U-shape, and is preliminarily laid over a position where the filling port of the empty cell installed with the filling port above is removed from the filling port. The method for manufacturing a flat fluorescent lamp according to claim 1, claim 2 or claim 3, wherein the sealing port is moved to a position where the sealing port is covered. 6. A pair of glass substrates, each having a light emitting layer composed of an electrode layer, a phosphor layer, and a dielectric layer, facing each other at appropriate intervals on the side of the light emitting layer so that the edges are made of low melting point glass. In a flat fluorescent lamp in which a discharge chamber is formed by sealing with a sealing frame, and a rare gas and mercury are sealed in the discharge chamber, exhaust gas, rare gas sealing, and mercury sealing are sealed in the sealing frame. There is a fill port for doing
A flat fluorescent lamp characterized in that the sealing port is sealed by a sealing member made of the same material as the glass substrate via a bonding layer made of the same material as the sealing frame. .