JP3374612B2 - Manufacturing method of fluorescent lamp - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a manufacturing method of the fluorescent lamp.

[0002]

2. Description of the Related Art FIGS. 3 and 4 show a conventional straight tube type fluorescent lamp (first conventional example). This fluorescent lamp is made of glass and is a substantially straight tube-shaped translucent airtight container. A phosphor 2 is applied to the inner wall of the electrode 1, a discharge gas containing an inert gas such as argon gas and mercury is sealed inside, and electrodes 3 are provided at both ends of the inside.

Then, by applying a voltage to the electrodes 3 at both ends in the transparent airtight container 1, a discharge is caused between the electrodes 3, and ultraviolet rays A radiated from mercury due to the discharge in the low-pressure mercury vapor, When the fluorescent substance 2 applied to the inner wall of the transparent airtight container 1 is made incident, the fluorescent substance 2 is excited by the energy of the ultraviolet rays A to be converted into visible light B, and the visible light B is transmitted transparently. It is designed to be radiated to the outside of the container 1. In FIG. 2, reference numeral 4 denotes discharge plasma generated in the translucent airtight container 1.

Although not shown, another conventional fluorescent lamp (second conventional example) is disclosed in Japanese Patent Laid-Open No. 63-11635.
As disclosed in Japanese Unexamined Patent Publication No. 2 (1998), a protective film made of aluminum oxide (alumina) is formed on the particle surface of the phosphor, and the phosphor coated with this protective film is adhered to the inner wall of the translucent airtight container. Known fluorescent lamps are also known.

[0005]

However, in the fluorescent lamp shown in the first conventional example configured as described above, the translucent hermetic container is used even though the fluorescent lamp is a lamp having high luminous efficiency. The phosphor 2 applied to the inner wall of No. 1 is deteriorated due to factors such as bombardment of mercury ions and argon ions in the discharge plasma 4 generated in the translucent airtight container 1 during lighting, and adhesion of mercury. As a result, there is a problem in that the brightness is reduced and the luminous flux maintenance factor is significantly reduced.

Further, in the fluorescent lamp shown in the second conventional example, since the particle surface of the phosphor is covered with the protective film of alumina, the deterioration of the phosphor is reduced to some extent, but still not sufficient. However, there is a problem that the luminous flux maintenance factor decreases.

[0007] The present invention has been made in view of the above problems, and an object is to phosphor to provide a method for manufacturing a hard fluorescent lamps which deteriorate.

[0008]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a first aspect of the present invention in which a discharge gas is enclosed and a phosphor 2 is applied to the inner wall. painting Bei the light-transmissive airtight envelope 1, particles 2a of the phosphor 2
A protective film 5 whose surface includes a metal oxide homogeneous portion 5a formed by a chemical reaction and a metal oxide fine particle powder 5b.
A method of manufacturing a fluorescent lamp coated by
The phosphor 2, the fine particle powder 5b, and a metal salt aqueous solution
And are dispersed in the thickener aqueous solution and then the pH is adjusted to
Form a dispersion liquid, and apply the dispersion liquid to the inner wall of the transparent airtight container 1.
Of the transparent airtight container 1
The surface of the particles 2a of the phosphor 2 attached to the inner wall is chemically reacted.
The homogeneous portion 5a made of the metal oxide formed by
The protective film 5 is formed by simultaneously depositing the particle powder 5b.
It is characterized by having done .

According to the invention of claim 2, in the method of manufacturing the fluorescent lamp according to claim 1, the metal oxide forming the homogeneous portion 5a is aluminum oxide, and the fine particle powder 5b is It is characterized by being aluminum oxide powder.

[0010]

[0011]

[0012]

Figure 1 DETAILED DESCRIPTION OF THE INVENTION, participation of the fluorescent lamp of the present invention
Is indicative of Reference Example, the fluorescent lamp is a fluorescent lamp of the straight tube, a light-transmissive airtight envelope 1 which phosphor 2 is applied to the inner wall, electrodes 3 disposed at both ends, And a base 6.

The translucent airtight container 1 is made of a translucent member such as soda lime glass, and has a tubular portion 1a formed in a substantially straight tube shape, and both end portions of the tubular portion 1a. Is hermetically sealed with a stem 1b made of, for example, lead glass or the like. Further, a discharge gas containing an inert gas such as argon gas and mercury is sealed inside the light-transmitting hermetic container 1.

The cylindrical portion 1a of the transparent airtight container 1
The phosphor 2 is applied to the inner wall of the
On the surface of the particles 2a of the above, a homogeneous portion 5a made of aluminum oxide (alumina) which is a metal oxide formed by a chemical reaction, and an alumina which is a fine particle powder 5b of the metal oxide having a diameter smaller than that of the particles 2a of the phosphor 2 are formed. It is formed by being covered with a protective film 5 formed of powder. The phosphor 2 having such a protective film 5 is formed on the inner wall of the cylindrical portion 1a of the translucent airtight container 1 as follows.

That is, first, 100 g of a barium magnesium aluminate phosphor activated with divalent europium, which is the phosphor 2, and 10 ml of an aluminum chloride aqueous solution, which is a 10% metal salt aqueous solution, are dispersed in 500 ml of pure water. Then, ammonia water is dropped so that the pH becomes about 9 while stirring. Then, after the dispersion was allowed to settle, the supernatant liquid was removed and the particles were washed thoroughly with pure water to obtain particles 2
A phosphor 2 having aluminum hydroxide adsorbed on the surface of a is obtained. Next, a drying treatment is performed to oxidize the aluminum hydroxide on the surface of the particles 2a of the phosphor 2 to obtain the phosphor 2 in which the surface of the particles 2a is covered with the homogeneous part 5a of aluminum oxide (alumina) which is a metal oxide. . Then, the phosphor 2 covered with the homogeneous portion 5a and the aluminum oxide powder (alumina powder) which is the fine particle powder 5b of about 3 to 7 wt% with respect to the phosphor 2 are treated with a thickener. After being dispersed in an aqueous solution of a certain polyethylene oxide and applied to the inner wall of the tubular portion 1a of the transparent airtight container 1, baking is performed to form particles on the inner wall of the tubular portion 1a of the transparent airtight container 1. The phosphor 2 having a surface 2a covered with a protective film 5 containing a homogeneous portion 5a of alumina by a chemical reaction and a fine particle powder 5b of alumina powder is applied.

The electrode 3 is, for example, a double or triple coil filament of tungsten wire, and the surface of which is coated with an electron emissive material for activation treatment. Then, such an electrode 3 is connected and held at one end side of an introduction wire 7 implanted in the stem 1b, and a base 6 is provided outside the translucent airtight container 1 of the stem 1b. A lamp pin 8 to which the other end of the lead-in wire 7 is connected is protrudingly provided on the base 6.

The fluorescent lamp thus constructed is manufactured in the same manner as a normal fluorescent lamp except for the steps relating to the phosphor 2. Then, by applying a voltage between the electrodes 3 at both ends in the airtight container 1, a discharge is caused between the electrodes 3, and ultraviolet rays emitted from mercury by the discharge in the low-pressure mercury vapor are emitted to the inner wall of the airtight container 1. By entering the applied phosphor 2, the phosphor 2 is excited by the energy of the ultraviolet rays to be converted into visible light, and the visible light is emitted to the outside of the airtight container 1.

With this structure, in the fluorescent lamp according to the reference example , the surface of the particles 2a of the phosphor 2 is covered with the homogeneous portion 5a of alumina all around,
Further, since the surface thereof is covered with the fine particle powder 5b which is the alumina powder adhered to the homogeneous portion 5a to form the protective film 5 containing the protective material of two types, it is possible to prevent the fluorescent lamp from being turned on. It is possible to remarkably prevent the phosphor 2 from being deteriorated by bombarding due to mercury ions or argon ions in the discharge plasma generated in the transparent airtight container 1. Therefore, the luminous flux maintenance factor of the fluorescent lamp is improved, and the lamp life can be extended.

In the reference example , the fine particle powder 5b is used.
The aluminum oxide powder (alumina powder) is used in an amount of about 3 to 7 wt% with respect to the phosphor 2. However, the inventors of the present invention have found that when the ratio is 0.2 wt%, the phosphor 2 deteriorates. There is almost no suppression effect, and when it is as high as 15 wt%, the result is that the light transmittance decreases, and the appropriate amount of the fine particle powder 5 b is several wt% to 10 wt% with respect to the phosphor 2. I confirmed that there is.

[0020] FIG. 2 shows the implementation in the form of a fluorescent lamp of the present invention, the reference example differs from the phosphor 2
The protective film 5 formed on the surface of the particles 2a and the method for forming the same, and the other configurations are similar to those of the reference example .

The protective film 5 is formed by having a metal oxide homogeneous portion 5a by a chemical reaction and a fine particle powder 5b. Due to the difference in the forming method, the fine particle powder 5b is a homogeneous portion 5.
It is configured to be scattered in a. Hereinafter, the forming method will be described in detail.

That is, first, 100 g of phosphor 2 and 10
% Aluminum salt aqueous solution of 10% aqueous solution of aluminum chloride
1 and aluminum oxide powder (alumina powder), which is a metal oxide fine particle powder 5b of about 3 to 7 wt% with respect to the phosphor 2, are dispersed in a thickener aqueous solution of polyethylene oxide. Then, ammonia water is dropped so that the pH becomes about 9 while stirring. Then, this dispersion liquid is applied to the inner wall of the cylindrical portion 1a of the transparent airtight container 1 and then fired, so that the surface of the particles 2a is subjected to a chemical reaction to obtain a homogeneous portion 5a of alumina and a fine particle powder 5b of alumina powder. The two types of protective materials are simultaneously applied to form the protective film 5, and the phosphor 2 is applied to the inner wall of the tubular portion 1a of the translucent airtight container 1.

Even with such a construction, the same effect as the fluorescent lamp in the above-mentioned reference example can be obtained, and the protective film 5 made of two kinds of protective materials of the homogeneous portion 5a and the fine particle powder 5b can be simultaneously formed and manufactured. easy.

It should be noted that according to the prior you facilities has been described as being perforated electrode having an electrode 3 fluorescent lamps a straight tube, the present invention is not limited to this, round and compact It may have any shape such as a shape, and may be an electrodeless fluorescent lamp having no electrodes. Further, in accordance with the prior you <br/> facilities, the phosphor 2, but was activated barium magnesium aluminate phosphor divalent europium, the present invention is not limited to this, such as cerium terbium Other phosphors such as co-activated lanthanum phosphate phosphor may be used, and the homogenous portion of the metal oxide and the fine particle powder of the metal oxide may be, for example, silicon oxide or magnesium oxide. May be.

[0025]

As described above, according to the present invention, the surface of the phosphor particles is adhered to the homogeneous part of alumina and the surface thereof. Since a protective film containing two types of protective materials is formed by being covered with the fine particle powder, the mercury ions and argon in the discharge plasma generated in the translucent airtight container during the lighting of the fluorescent lamp. Deterioration of phosphor by ion bombardment is improved , and two kinds of protection, homogeneous part and fine particle powder, are protected.
A protective film made of material can be formed at the same time, which facilitates manufacturing.

[0026]

[0027]

[Brief description of drawings]

FIG. 1 shows a reference example of a fluorescent lamp of the present invention, (a) is a partial cross-sectional front view of a main part, and (b) is a schematic view showing a protective film formed on the surface of phosphor particles. It is a figure.

2 is a schematic diagram showing a protective film of the phosphor particle surface of implementation in the form of a fluorescent lamp of the present invention.

FIG. 3 is a partial cross-sectional front view of an essential part showing the general structure of a straight tube fluorescent lamp.

FIG. 4 is a cross-sectional view showing a main part of a conventional fluorescent lamp (first conventional example).

[Explanation of symbols]

1 Translucent airtight container 2 phosphor 2a particles 5 protective film 5a homogeneous part 5b Fine particle powder

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-61-23678 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01J 61/46 H01J 9/22

Claims (2)

(57) [Claims] 1. A with an internal discharge gas is enclosed, e Bei the light-transmissive airtight envelope which phosphors are coated on the inner wall, the particle surface of the phosphor, the metal oxide formed by chemical reaction A method for producing a fluorescent lamp, which comprises a homogeneous part and a protective film containing a fine particle powder of metal oxide ,
Increase the amount of the phosphor, the fine particle powder, and the metal salt aqueous solution.
After dispersing in a sticky solution, adjust the pH to form a dispersion.
And then apply the dispersion liquid to the inner wall of the transparent airtight container.
Then, it is baked and attached to the inner wall of the transparent airtight container.
Formed by chemical reaction on the surface of phosphor particles
Simultaneously coat the homogenous part of the metal oxide with the fine particle powder.
Fluorescence characterized in that the protective film is formed by coating
Lamp manufacturing method. 2. The method for manufacturing a fluorescent lamp according to claim 1, wherein the metal oxide forming the homogeneous portion is aluminum oxide, and the fine particle powder is aluminum oxide powder.