JPH11283564A - Fluorescent lamp and luminaire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluorescent lamp with a photocatalyst film which effectively oxidizes and decomposes adsorbed materials so that dirty materials are not left on the bulb outer surface, and provide a luminaire using this fluorescent lamp. SOLUTION: This fluorescent lamp has a tubular bulb 1 in which a phosphor layer 7 is formed on the inner surface and an electrode 4 is sealed at each end, a base 9 fixed to the end of the bulb 1, and photocatalyst film 6 formed on the outer surface of the bulb 1 so that a film formed edge part 10 is positioned on the electrode 4 side than on the intermediate position C in the length from a bulb electrode portion A to a bulb end part B. Desirable photocatalytic activity is developed by effectively oxidizing, decomposing adsorbed materials with the photocatalyst film 6, dirty materials are not left on the bulb 1 outer surface, and the outer appearance of the fluorescent lamp with not be damaged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent lamp having a photocatalyst film formed on an outer surface.

[0002]

2. Description of the Related Art A fluorescent lamp with a photocatalytic film in which a photocatalytic film such as titanium oxide is formed on the outer surface of a fluorescent lamp is disclosed in Japanese Patent No. 2545.
No. 727, the photocatalytic activity of receiving near-ultraviolet light contained in light emitted from a fluorescent lamp
Since the organic compound adhering to the surface is decomposed, it is difficult for dirt to adhere to the lamp surface during lighting, and it has an effect of deodorizing because it decomposes the odor source in the air.

[0003] Generally, a fluorescent lamp is configured to minimize the emission of ultraviolet light outside the fluorescent lamp. However, near ultraviolet light such as 365 nm which is a mercury emission line is slightly emitted. The photocatalytic film is activated by the irradiation of the near ultraviolet rays, and exhibits an oxidizing and decomposing power.

[0004] Among the metal oxides used for the photocatalyst film, for example, titanium oxide (TiO2) has a strong photocatalytic activity and is excellent in ease of production and economical efficiency. Many are used. One of the reasons that titanium oxide has excellent photocatalytic activity is that it has a high ability to adsorb suspended substances. If the adsorbing power of the suspended matter is high, the pollutant in the air is adsorbed and decomposed by the photocatalytic activity, so the fluorescent lamp is exposed to the atmosphere and turned on, so that the pollutant in the atmosphere is decomposed effectively. .

[0005]

However, the intensity of ultraviolet light emitted from the fluorescent lamp on the outer surface of the bulb is highest between the two electrodes where the discharge path is formed, and decreases as the position approaches the base from the electrode portion.

For this reason, in a part of the region from the electrode site to the bulb end, the photocatalytic film has low activity due to low ultraviolet intensity.

On the other hand, the photocatalyst film formed of titanium oxide or the like has a high ability to adsorb floating substances, and therefore, even if a portion having a low photocatalytic film activity adsorbs floating substances, the adsorbed substance is not effectively decomposed without decomposing. It is also conceivable that, for example, the components may remain in the tobacco sheath, and consequently, they may easily become dirty.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a fluorescent lamp with a photocatalytic film in which a photocatalytic film effectively oxidizes and decomposes an adsorbed substance so that a contaminated substance does not remain on the outer surface of the bulb. An object is to provide a lighting device using a lamp.

[0009]

According to the present invention, there is provided a fluorescent lamp comprising: a tubular bulb having a phosphor layer formed on an inner surface and electrodes sealed at both ends; a base attached to an end of the bulb; A photocatalyst film formed on the outer surface of the bulb such that the film-forming edge is located closer to the electrode than the intermediate position of the length from the site to the bulb end.

A fluorescent lamp according to a second aspect of the present invention comprises a tubular bulb having a phosphor layer formed on an inner surface and electrodes sealed at both ends; a base attached to the bulb end; and a bulb having an ultraviolet intensity between the two electrodes. And a photocatalyst film formed on the outer surface of the bulb so that a film is not formed in a region from the bulb electrode site to the bulb end, which is less than 50% of the ultraviolet intensity of the site. .

A third aspect of the present invention is the fluorescent lamp according to the first or second aspect, wherein the photocatalytic film is mainly composed of anatase crystalline titanium oxide.

According to a fourth aspect of the present invention, there is provided a lighting apparatus comprising: an apparatus main body; and the fluorescent lamp according to any one of the first to third aspects, which is detachably mounted on the apparatus main body.

In each of the above claims and the following claims, definitions of terms are given in the following description, unless otherwise specified.

The bulb is made of soda lime glass, lead glass or the like, but may be made of ceramics as long as it is translucent.

As the fluorescent lamp, not only a straight tube but also a ring-shaped lamp, a bent lamp, or the like having a base attached to its end can be used.

The electrode is a hot cathode, a cold cathode, or the like, but may be an external electrode such as an electric field generating type electrode or an induction coil attached to the outer surface of the bulb as long as it causes a discharge.

The phosphor is a white phosphor such as a three-wavelength phosphor or a calcium halophosphate phosphor, but may be a phosphor that generates near-ultraviolet light.

The base may have any suitable structure corresponding to the form of the fluorescent lamp, and the material may be a metal or a plastic such as PBT (polybutylene terephthalate). .

The photocatalytic film must not be formed on the outer surface of the bulb having a low ultraviolet intensity. Although relative, 50% of the UV intensity at the bulb between the two electrodes
It is a rule of thumb not to form it in the part where the value is less than. However, even if the relative intensity exceeds 50%, the formation of a photocatalytic film at the site should be avoided if the ultraviolet intensity is such that the photocatalytic activity is not effectively exerted. For example, even when the relative intensity of ultraviolet rays is 80%, the desired photocatalytic activity cannot be obtained due to factors such as the thickness of the photocatalytic film, and the outer surface of the bulb is contaminated by the adsorption of contaminants. It is desirable not to form them.

Generally, if the distance from the bulb electrode to the bulb end is closer to the electrode than the intermediate position, the ultraviolet intensity is at a level at which photocatalytic activity can be effectively exerted. The photocatalytic film should be formed so that the film forming edge is located inside.

The photocatalyst film is formed by the following method (a) or (b).

(A) A portion where no photocatalyst film is formed is masked in advance, a photocatalyst film is formed on the outer peripheral surface of the bulb, and the masking is removed, followed by drying and baking.

(B) adjusting the length in the tube axis direction of the photocatalyst suspension exposed from the suspension tank which is elongated along the tube axis direction, in accordance with the portion where the photocatalyst film is not formed, The photocatalyst suspension is applied by rotating the valve in the circumferential direction, and then dried and baked.

The photocatalyst suspension is composed of TiO2 fine particles and S
A suspension prepared by dispersing iO2 fine particles in a mixed solvent of butyl acetate-butyl alcohol is used. The binder component used in the coating agent is not limited to SiO2 fine particles, and various binder components can be applied. A well-known mixed solvent may be used.

As the photocatalytic film, titanium oxide (TiO2) is optimal from the viewpoint of photocatalytic effect and production cost. However, if the film has a light-transmitting property when formed into a film, for example, WO3, LaRhO3. FeTiO3, Fe2O3, CdF
e2O4, SrTiO3, CdSe, GaAs, GaP, R
Fine particles of a compound having a photocatalytic action such as uO2, or a mixture of two or more kinds of fine particles may be used.

The photocatalyst film is formed of a binder component such as TiO2 and SiO2, but may be formed mainly of TiO2. The thickness of the photocatalyst film is about 0.01 to 1 μm in the case of the alcoholate film type.
In the case of a fine particle film type, the average particle diameter is 0.007 to 0.05 μm
It is preferable to use fine particles of a degree.

The lighting equipment includes indoor ceiling-mounted or hanging lighting equipment, outdoor lighting equipment, and the like.

According to the fluorescent lamp or the luminaire of the above-mentioned claims, no photocatalytic film is formed on the outer surface of the bulb having a low ultraviolet intensity, so that no contaminants remain on the outer surface of the bulb, and the photocatalytic film is formed. A desired photocatalytic activity is exhibited by effectively oxidizing and decomposing the adsorbed substance.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a partially cutaway sectional view schematically showing the fluorescent lamp of the first embodiment.

The fluorescent lamp is FL40SS according to JIS standard.
Is a low-pressure mercury vapor discharge lamp having a rated power of 37 W, and 1 is an arc tube as a bulb having a straight tube shape. This arc tube 1 has a bulb outer diameter of 28 mm and a tube length of 11
It is made of glass having a size of about 98 mm and transmitting ultraviolet rays of about 300 nm or more, for example, soda lime glass. The two ends of the arc tube 1 are sealed by stems 2, 2, and lead wires 3, 3 are hermetically penetrated through the stems 2, 2. Further, filament electrodes 4 and 4 as electrode means formed in a double coil by a tungsten wire or the like are attached to the lead wires 3 and 3, and an emitter (not shown) is applied.

Further, a photocatalytic film 6 (shown by a broken line in FIG. 1) is formed on the outer surface exposed to the outside of the arc tube 1. Here, the photocatalyst film 6 is made of, for example, TiO2
(Titanium oxide), mainly having an average particle size of 0.0
It is composed of fine particles of anatase type TiO2 of 5 to 0.2 μm and fine particles of SiO2 (binder component).

Numeral 7 denotes a phosphor layer formed on the inner surface of the arc tube, which is excited by ultraviolet rays emitted from mercury and converts it into visible light.

The phosphor layer 7 is mainly composed of a three-wavelength phosphor. Examples of the three-wavelength light emitting phosphor include Y2O3: Eu as a red phosphor having a peak wavelength near 610 nm, and LaPO4: Ce, Tb as a green phosphor having a peak wavelength near 540 nm.
(SrCaBa) 5 (PO4) 3Cl: Eu is used as a blue phosphor having a peak wavelength near 450 nm.

Further, a predetermined amount of mercury and an inert gas such as an argon gas are sealed in the arc tube 1, and caps 9, 9 each having a cap pin 8 projecting from an end of the arc tube 1.
Is attached. The base pins 8 are connected to the filament electrodes 4 and 4 via the lead wires 3.

It should be noted that the phosphor layer 7 may be formed by mixing an ultraviolet light emitting phosphor which emits ultraviolet light of 300 to 400 nm excited by ultraviolet light emitted from mercury with a three-wavelength light emitting phosphor. As the ultraviolet light emitting phosphor, at least one or more of europium-activated alkaline earth metal borates, lead-activated silicates, europium-activated alkaline earth metal aluminates, and phosphors in which halogen is added to these are used. Used. As a europium-activated alkaline earth metal borate, for example, Sr2 B2 O7: E2 + having a peak wavelength at 368 nm is effective, and as a lead-activated silicate, a peak wavelength at 370 nm is used (Ba, S
(r, Mg) 3Si2O7: Eu2 +, BaSi2O5: Pb2 + having a peak wavelength at 350 nm, and the like are preferable, and as the europium-activated alkaline earth metal aluminate, 3 is preferable.
Those having a peak wavelength in the range of 58 to 360 nm are effective.

FIG. 2 is a partially enlarged side view schematically showing the fluorescent lamp of the first embodiment.

In the fluorescent lamp of this embodiment, the photocatalytic film 6 is positioned such that the film forming edge 10 is located closer to the electrode 4 than the intermediate position C having a length L from the bulb electrode portion A to the bulb end B.
Are formed on the outer surface of the arc tube 1.

The valve electrode portion A is larger than the film forming edge 10.
The ultraviolet intensity on the outer surface of the arc tube 1 on the side is 50% when the ultraviolet intensity on the outer surface portion of the arc tube 1 between the electrodes 4 and 4 is 100%.
That is all. On the other hand, the ultraviolet intensity on the outer surface of the arc tube 1 closer to the bulb end B than the film-forming edge 10 decreases as it approaches the bulb end B, and becomes less than 50% near the bulb end B. .

Next, the operation of the fluorescent lamp of this embodiment will be described.

When the fluorescent lamp is turned on, mercury vapor emits ultraviolet rays of 185 nm and 254 nm specific to mercury due to arc discharge between the electrodes 4 and 4.
To excite. In this case, the three-wavelength light emitting phosphor of the phosphor layer 7 emits visible light having a peak wavelength in three wavelength regions. The visible light emitted by the three-wavelength light emitting phosphor passes through the tube wall of the arc tube 1 and passes through the photocatalytic film 6 and is emitted to the outside, so that a predetermined amount of visible light is obtained. Can be illuminated.

On the other hand, a small amount of ultraviolet rays, such as 365 nm of mercury emission lines, is emitted from the arc tube 1 by arc discharge, and the ultraviolet rays pass through the tube wall of the arc tube 1 and reach the photocatalytic film 6. The photocatalyst film 6 functions to absorb the ultraviolet rays, generate photocatalytic activity on the surface of the photocatalyst film 6, and efficiently oxidize and decompose odors and organic substances that contaminate the surrounding environment.

For example, odor (acetaldehyde concentration 1
The fluorescent lamp of this embodiment was turned on in a sealed atmosphere having a concentration of 300 ppm), and the change in the lighting time and acetaldehyde concentration was measured.
m, it was confirmed to exhibit an excellent photocatalytic function of about 5 ppm after 24 hours.

According to the fluorescent lamp of the present embodiment, it emits required visible light as an illumination light source, and also functions as an ultraviolet light source for the photocatalyst film 6 applied to the surface.
Lighting and air purification of living spaces such as houses and offices can be realized with a single fluorescent lamp, and a comfortable living environment can be obtained. Further, even if dust, cigarette tar, oil and fat components accumulate on the outer surface of the fluorescent lamp, the oxidative decomposition of the photocatalyst film 6 prevents the adhesion of these substances. On the other hand, since the standard display and the like of the fluorescent lamp are maintained sharply, maintenance is facilitated in combination with prevention of a decrease in luminous flux due to the photocatalytic action and elimination of wiping and cleaning of the fluorescent lamp.

Since the photocatalyst film 6 is not formed on the outer surface of the arc tube 1 having a low ultraviolet intensity, the photocatalyst film 6 effectively oxidizes and decomposes the adsorbed substance, thereby exhibiting a desired photocatalytic activity. At the same time, no contaminants remain on the outer surface of the arc tube 1, and the appearance of the fluorescent lamp is not impaired.

In each of the embodiments described above, the straight tube fluorescent lamp has been described.
It may be a fluorescent lamp having a letter shape or a double U shape.

If the light source is not used for illumination,
Even when replacing with a low-pressure mercury vapor discharge lamp such as a fluorescent lamp in which a phosphor layer is formed only with an ultraviolet phosphor or a germicidal lamp in which no phosphor is formed in an arc tube, the same effects as those of the above embodiments can be obtained. it can.

Further, as a substance having a photocatalytic action, in addition to TiO2 (titanium oxide), ZnO (zinc oxide) CeO2 (cerium oxide), Tb2O3 (terbium oxide), MgO (magnesium oxide), Er2O3 (erbium oxide) Or a mixture of two or more of these,
Further, a mixed form such as zeolite may be employed.

[0049]

According to the fluorescent lamp or the luminaire of the present invention, since the photocatalytic film is not formed on the outer surface of the bulb having a low ultraviolet intensity, the photocatalytic film effectively oxidizes and decomposes the adsorbed substance. The desired photocatalytic activity is exhibited, and no contaminants remain on the outer surface of the bulb, so that the appearance of the fluorescent lamp is not impaired.

[0050]

[Brief description of the drawings]

[0051]

FIG. 1 is a partially cutaway sectional view schematically showing a fluorescent lamp according to a first embodiment of the present invention.

[0052]

FIG. 2 is a partially enlarged side view schematically showing the fluorescent lamp.

[0053]

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Valve, 4 ... Electrode, 9 ... Base, 6 ... Photocatalytic film, 7 ...
Phosphor layer, 10: film forming edge, A: bulb electrode site,
B: Valve end, C: Middle position.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hitoshi Kono Toshiba Litec Co., Ltd. 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo

Claims (4)

[Claims] 1. A tubular bulb having a phosphor layer formed on an inner surface and electrodes sealed at both ends; a base attached to the bulb end; and a middle position of a length from the bulb electrode site to the bulb end. A photocatalytic film formed on the outer surface of the bulb such that the film-forming edge is located on the electrode side. 2. A tubular bulb having a phosphor layer formed on an inner surface thereof and electrodes sealed at both ends; a base attached to an end of the bulb; A photocatalyst film formed on the outer surface of the bulb so that a film is not formed in a region from the bulb electrode portion to the bulb end, which is less than 50%. 3. The fluorescent lamp according to claim 1, wherein the photocatalytic film is mainly composed of titanium oxide in anatase crystal form. 4. A lighting apparatus comprising: an apparatus main body; and the fluorescent lamp according to claim 1, which is detachably mounted on the apparatus main body.