JPH05166490A - Instant starting fluorescent lamp and manufacture of the same - Google Patents

Abstract

PURPOSE:To provide an instant starting fluorescent lamp having an improved lumen maintenance factor reduction. CONSTITUTION:A method of manufacturing an instant starting fluorescent lamp comprising a transparent conductive film formed in the inner surface of a glass tube, an aluminium oxide film formed on the transparent conductive film, and a phosphor film formed on the aluminium oxide film is characterized in that when forming the aluminium oxide film, an aluminium oxide prepared by dispersing, with an agitation type wet medium mill, an aluminium oxide obtained through hydrolysis or alum method of an aluminium alkoxide, is used as the aluminium oxide having an average secondary particle size of 1.0mum or less and a BET specific surface area of 120m<2>/g or more, is used as the aluminium oxide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an instant start type fluorescent lamp, and more particularly to an instant start type fluorescent lamp having an improved luminous flux maintenance factor and a manufacturing method thereof.

[0002]

Description of the Prior Art An immediate start type fluorescent lamp is formed by forming a transparent conductive coating on the inner surface of a glass tube which constitutes a conventional fluorescent lamp, and applying a fluorescent coating on the transparent conductive coating. It was However, a fluorescent lamp with such a configuration not only spoils the appearance of the lamp by causing black-brown spots during long-time lighting or a coloring phenomenon of coloring the entire lamp in yellow, but also has a luminous flux maintenance factor. There is a problem that the life of the fluorescent lamp is shortened due to the remarkable deterioration. As a means for solving such a problem, it has been conventionally known to provide a protective coating made of aluminum oxide between the transparent conductive coating and the phosphor coating. Since aluminum oxide used for such an application is fine particles, it is necessary to impart a coating film having excellent adhesiveness, glossiness and light transmittance, and therefore, the average primary particle diameter is usually several mμ to 100.
Aluminum oxide with an average secondary particle diameter of about mμ and a sub-micron average is used, but the primary particles of these fine particles have a strong cohesive force, except for aluminum oxide obtained by the vapor phase decomposition method of aluminum chloride. For example, aggregated particles (secondary particles) of 1 μm or less are not known.

Therefore, as the aluminum oxide for such use, the average primary particle diameter obtained by the vapor phase thermal decomposition method of aluminum chloride is about 5 mμ to about 100 mμ and the secondary particle diameter of the usage form is 1 μm or less. Commercially available aluminum oxide (for example, Aluminumu Oxide C manufactured by Degussa) is used, and although it has some improvement effect in preventing coloration and deterioration of luminous flux maintenance factor, the effect is not yet fully satisfied.

[0004]

In view of such circumstances, the inventors of the present invention have diligently studied in order to find an excellent immediate start type fluorescent lamp having an effect of preventing a decrease in luminous flux maintenance factor, and as a result, a specific secondary When using aluminum oxide having a particle size and a specific surface area, and further when using aluminum oxide obtained by a specific production method as a specific physical property by dispersing it, an immediate start type fluorescent lamp in which the above object is solved The present invention has been completed and the present invention has been completed.

[0005]

That is, according to the present invention, a transparent conductive film is formed on the inner surface of a glass tube, an aluminum oxide film is formed on the transparent conductive film, and a phosphor film is further formed on the aluminum oxide film. In an immediate start type fluorescent lamp formed by forming an aluminum oxide film, the average secondary particle diameter is 1.0 μm or less and the BET specific surface area is 12
Another object of the present invention is to provide an immediate start type fluorescent lamp characterized by using 0 m ² / g or more of aluminum oxide.

Furthermore, a transparent conductive coating is formed on the inner surface of the glass tube, an aluminum oxide coating is formed on the transparent conductive coating, and a fluorescent coating is further formed on the aluminum oxide coating. In the shape fluorescent lamp,
Aluminum oxide obtained by hydrolyzing aluminum alkoxide as the aluminum oxide or alum is used for the formation of the aluminum oxide film is dispersed by a stirring type wet medium mill, the average secondary particle diameter is 1.0 μm or less, and the BET specific surface area is 120 m. Another object of the present invention is to provide an immediate start type fluorescent lamp characterized by using ² / g or more of aluminum oxide.

The present invention will be described in more detail below. The aluminum oxide used in the present invention has an average secondary particle diameter of about 1.0 μm or less, preferably about 0.3 μm to about 0.8 μ, after being dispersed by a stirring type wet medium mill.
m, BET specific surface area of about 120 m ² / g or more, more preferably about 130 m ² / g or more,
Although not particularly limited, the average primary particle size is usually about 0.1.
Aluminum oxide obtained by a hydrolysis method of an aluminum alkoxide or an alum method having an average secondary particle size of not more than 10 μm, preferably not more than about 5 μm, is used.

Of aluminum oxide used as a coating material
Contact when the average secondary particle size exceeds 1.0 μm
Possibly due to a decrease in the number of points, but the adhesive strength is reduced.
As a result, the luminous flux maintenance factor decreases and, on the other hand, the particles become finer.
Therefore, although light transmission and adhesion strength are high, fine particles
In order to do this, it takes a long time to disperse the data.
The pollution from them increases. Therefore the light transmission and peeling of the coating
Considering the prevention effect, it is usually in the range of about 0.3 μm to about 1.0 μm.
It is carried out in the fence. The specific surface area is about 120m.²/ G
If it is less than
It seems that it is due to the decrease, but the adhesive strength becomes weaker,
As a result, the luminous flux maintenance factor decreases. The upper limit of the specific surface area is
It is not limited to but usually about 200m ²/ G if about
It can be manufactured industrially.

As the aluminum oxide which can satisfy the above physical properties in the dispersion by the stirring type wet medium mill, the aluminum oxide obtained by the hydrolysis method of aluminum alkoxide or the alum method as described above is used. The specific surface area of aluminum oxide obtained by the thermal decomposition method of aluminum chloride currently on the market is 100 m ² / g at most, and it is difficult to obtain alumina having a desired specific surface area.

As the aluminum oxide disperser used in the present invention, a stirring type wet medium mill is used. Specifically, a Dyno mill manufactured by Shinmaru Enterprises Co., Ltd., an Ultra Visco mill manufactured by IMEX Co., or a sand mill using a medium having an average particle diameter of about 3 mm or less is used. Rolling ball mills, vibrating ball mills, planetary ball mills, etc. are generally used as a disperser for aluminum oxide, but these mills have insufficient dispersibility or are likely to cause re-agglomeration. Aluminum oxide of diameter is not obtained. It is preferable to use a stirring type wet medium mill having a medium, an inner wall of the mill, and a stirring portion made of ceramic or resin. Particularly, as ceramics, alumina which does not have a fear of contamination or has good wear resistance. Zirconia is preferred. When the material is metal or glass, the lamp luminous flux maintenance factor may decrease due to metal contamination and soda contamination, respectively.

Usually, aluminum oxide is dispersed in deionized water, but if necessary, a butyl acetate solution using nitrocellulose as a binder may be used. The medium used for dispersion preferably has a diameter of about 3 mm or less, more preferably about 0.3 mm to about 1 mm. If the medium is larger than about 3 mm, it takes a long time to disperse, and the raw material aluminum oxide to be dispersed has a broad particle size distribution.

The thus-prepared aluminum oxide slurry is prepared by a known method, for example, by holding a glass tube already coated with a transparent conductive film vertically and allowing the aluminum oxide slurry to flow down into the glass tube. The aluminum oxide film may be applied on the conductive film. Further, the formation of the phosphor coating on the aluminum oxide coating may be performed according to a known method.

[0013]

According to the present invention described in detail above, by using aluminum oxide having a specific average secondary particle diameter and specific surface area as a constituent raw material of the aluminum oxide coating, the light transmittance is lowered. It was able to remarkably improve the reduction of the luminous flux maintenance factor, and its industrial value is enormous.

[0014]

EXAMPLES The present invention will be described more specifically below with reference to examples, but the present invention is not limited to these examples. In the present invention, the secondary particle size of aluminum oxide was measured by a laser diffraction particle size analyzer (manufactured by Nikkiso Co., Ltd .; Microtrack particle size analyzer).

Example 1 and Comparative Example 1 AK manufactured by Sumitomo Chemical Co., Ltd. as aluminum oxide
5 parts of P-G15 (average secondary particle diameter 8 μm) was used as 95 parts of water.
Together with the zirconia beads of 0.6mmφ as a medium
Shinmaru Enterp with inner wall lined with alumina
Dizeno mill (stirring type wet medium
It was put into a container) and treated for a residence time of about 30 minutes. Got
Aluminum oxide having an average secondary particle diameter of 0.5 μm, specific surface
Product is 150m ²/ G. The amount obtained in this way
The aluminum oxide slurry after the dispersion treatment was held vertically
Outside the tube with a transparent conductive coating made of tin oxide on the inner surface
Flows into a glass tube with a diameter of about 32 mm and a tube length of about 1200 mm.
And apply aluminum oxide on the transparent conductive film
Then, it was dried by blowing warm air. Aluminum oxide coating
The amount of cloth was 250 mg. Then, similarly, suspend the fluorescent substance.
Let the liquid flow down, apply it on the aluminum oxide film, and dry it.
Then, a fluorescent film was formed. After that, 40 by the usual method
I made a w-type instant start type fluorescent lamp. In this way
After turning on the fluorescent lamp obtained by lighting for 1000 hours
The luminous flux maintenance factor was measured. (Luminous flux maintenance factor is 1000 hours
Luminous flux value after lighting for 100 hours
It is the% value divided by. ) For comparison, commercially available aluminum oxide; Degussa
Aluminumu OxideC (Average secondary particle size 0.9μ
m) was dispersed in the same manner as above. The resulting oxidation
Aluminum has an average secondary particle size of 0.5 μm and a specific surface area of
100m²/ G. This aluminum oxide
Apply in the same manner as above to create a paint, and then use the same method.
A fluorescent lamp was prepared and the luminous flux maintenance factor was measured. The result
It is shown in Table 1.

Example 2 Using the same aluminum oxide as used in Example 1, dispersion treatment was performed for 15 minutes with the same disperser as in Example 1. The obtained aluminum oxide had an average secondary particle diameter of 0.9 μm and a specific surface area of 150 m ² / g. Then, the aluminum oxide slurry of Example 1 was replaced by this aluminum oxide slurry, and the same procedure as in Example 1 was applied to produce a fluorescent lamp, and then the luminous flux maintenance factor was measured in the same manner as in Example 1. The results are shown in Table 1.

Example 3 In the method of Example 1, CR-125 (average secondary particle size: 2) commercially available from Baikovsky as aluminum oxide was used.
aluminum oxide obtained by the alum method of Example 1 was used.
The same dispersion machine was used for 30 minutes for dispersion treatment. The obtained aluminum oxide had an average secondary particle diameter of 0.5 μm and a specific surface area of 125 m ² / g. Next, a fluorescent lamp was manufactured in the same manner as in Example 1 except that this aluminum oxide was used in place of the aluminum oxide slurry of Example 1, and then the luminous flux maintenance factor was measured in the same manner as in Example 1. The results are shown in Table 1.
Shown in.

Comparative Examples 2 to 6 Commercially available aluminum oxides used in Examples 1 to 3 and Comparative Example 1 (aluminum alkoxide method--Comparative Example 2, alum method--Comparative Example 3, aluminum chloride method-- -Comparative example 4)
Is used as it is without being subjected to a dispersion treatment with a disperser, and AKP-G15 (average secondary particle diameter 8 μm, manufactured by Sumitomo Chemical Co., Ltd.).
m) An average secondary particle diameter of 1.5 μm and a specific surface area of 150 m obtained by dispersing 5 parts by weight and 95 parts by weight of water in a wet rolling ball mill using alumina balls of 10 mmφ for 24 hours.
^{Using 2} / g of aluminum oxide (Comparative Example 5), a fluorescent lamp was produced in the same manner as in Example 1, and the luminous flux maintenance factor was measured in the same manner as in Example 1. The results are shown in Table 1.

[0019]

[Table 1]

Claims (3)

[Claims] 1. An immediate start type in which a transparent conductive coating is formed on the inner surface of a glass tube, an aluminum oxide coating is formed on the transparent conductive coating, and a fluorescent coating is further formed on the aluminum oxide coating. In fluorescent lamps, the average secondary particle size is 1.0 μm when forming an aluminum oxide film.
Hereinafter, an immediate start-up type fluorescent lamp characterized by using aluminum oxide having a BET specific surface area of 120 m ² / g or more. 2. The immediate start type fluorescent lamp according to claim 1, wherein the aluminum oxide is aluminum oxide obtained by a hydrolysis method of an aluminum alkoxide or an alum method. 3. An immediate start type in which a transparent conductive coating is formed on the inner surface of a glass tube, an aluminum oxide coating is formed on the transparent conductive coating, and a fluorescent coating is further formed on the aluminum oxide coating. In a fluorescent lamp, for forming an aluminum oxide film, aluminum oxide obtained by hydrolysis of aluminum alkoxide as aluminum oxide or aluminum oxide obtained by alum method was dispersed by a stirring type wet medium mill to obtain an average secondary particle diameter of 1.0 μm. Hereinafter, a method for producing an immediate start type fluorescent lamp, characterized in that aluminum oxide having a BET specific surface area of 120 m ² / g or more is used.