JP2000100383A - Fluorescent lamp and light source device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maximally extract a beam deterioration preventing effect and a consumed mercury amount reducing effect. SOLUTION: This fluorescent lamp has a phosphor film 5, made of phosphor particles 50 formed on the internal surface (i.e., the side of an airtight space where a discharge plasma takes place) of a translucent airtight vessel 1, and a glass protective film 11 is formed between the internal surface of the translucent airtight vessel 1 and the phosphor film 5. Also, a surface protection layer 12 made of a metal oxide having a different starting material at introduction (or the introduction process for accompanying the material) and the same chemical composition of the final product for the glass protection film 11 is formed on the phosphor film 5 at the side of the airtight space. Furthermore, the fluorescent lamp so made is provided with an internal electrode, an external induction coil or the like, and a lighting device for feeding power to the internal electrode, the induction coil or the like is added, thereby constituting a light source device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphor film formed in a light-transmitting hermetically sealed container enclosing a discharge medium, and converts ultraviolet light emitted by discharge of the discharge medium into visible light by the phosphor film. The present invention relates to a fluorescent lamp and a light source device using the same.

[0002]

2. Description of the Related Art Fluorescent lamps are one of the important light sources widely used today. Generally, this light source generates ultraviolet rays by discharging the enclosed mercury, and converts the ultraviolet rays into visible light by a phosphor applied to the inner surface of the tube.

On the other hand, in recent years, awareness of global environmental problems has been rising more than ever, and mercury waste used in fluorescent lamps has been increasingly recognized as one of these environmental pollution sources.

[0004] Under such circumstances, various approaches to fluorescent lamps have been activated. For example, many studies have been made to abolish the use of mercury and reduce the amount of mercury used.

A harmless ultraviolet radiation source alternative to mercury aimed at eliminating the use of mercury is, for example, a rare gas fluorescent lamp using ultraviolet light (main wavelength: 147 nm) from xenon discharge. This light source has excellent features such as no luminous flux variation with respect to the ambient temperature and a good luminous flux rising characteristic after starting, as compared with a conventional fluorescent lamp utilizing mercury discharge. However, since it is much less efficient than mercury, it has already been put to practical use in some applications such as OA equipment, but it is difficult to substitute non-mercury fluorescent lamps in fields including general lighting applications. Is the current situation.

Therefore, at present, reduction of the amount of mercury used is a practical measure. Specific measures include, for example, the following. (A) Reduction of the amount of mercury enclosed per lamp (optimization to the minimum required) (b) Reduction of the amount of mercury used in a long-term view by reducing the frequency of lamp disposal by improving the lamp life First, (a) will be described. The mercury sealed in the lamp is gradually consumed by the inner surface of the glass bulb and the phosphor as the lighting time elapses. That is, after being adsorbed on these sites, mercury is deposited as various compounds by the reaction with components in the glass or the phosphor, the impurity gas remaining in the tube, and the like, and can no longer contribute to the discharge and is invalidated. Therefore, in order to avoid mercury depletion during the lamp life, excess mercury is filled. Therefore,
In order to reduce the amount of enclosed mercury, it is necessary to reduce the amount of mercury consumed in the tube, that is, to reduce the generation of ineffective mercury.

Next, (b) will be described. In general, the life deciding factors of fluorescent lamps are roughly classified into two, that is, so-called "luminous life" and "pointless life". The luminous flux life is due to discoloration or blackening of the surface of the glass bulb or the phosphor, or a decrease in luminous efficiency due to aging of the phosphor itself, and the like.
The spot life is caused by disconnection of the electrode base material or consumption of thermionic emission material (emitter) applied thereto. As described above, the life of the fluorescent lamp is generally defined by the shorter one of the life of the light beam due to the deterioration of the light beam and the lifetime of the spot due to the electrode being cut.

Among these, the luminous flux life is related to the formation and deposition of compounds due to the reaction of mercury with phosphor components, alkali components in glass or residual impurities in tubes, and deterioration of phosphor due to ion bombardment of mercury and rare gases. Further, it is considered that the phosphor is deteriorated by ultraviolet rays. As measures against these problems, improvements in phosphors and development of a transparent protective film on the inner surface of glass have been made. On the other hand, in a general fluorescent lamp having an electrode (filament) inside the lamp, there is essentially a limit to the improvement of the defective life, which is a constraint on the life improvement.

[0009] From such a viewpoint, an “electrodeless fluorescent lamp” having no electrode inside the lamp has recently been particularly spotlighted,
Some have already been put to practical use. In this type of lamp, mercury and a rare gas are sealed in an airtight space formed by a translucent member such as glass, similarly to the above-described (electrode) fluorescent lamp, but an electrode is provided inside the lamp. Instead, by exciting the sealed gas by an induction coil arranged outside the lamp, a discharge is generated in the hermetic space, and the ultraviolet light emitted thereby excites the fluorescent film formed on the inner surface of the hermetic container. Obtain visible light. Since this kind of light source literally has no electrode inside the lamp, the above-mentioned electrode life does not exist, and the life is substantially determined by the luminous flux life, so that a longer life can be expected in principle than an electrode lamp. . Therefore, in this type of light source, it is important to improve the luminous flux maintenance rate more than before.

As described above, two important issues in the field of fluorescent lamps in the future are reduction of mercury consumption in the lamp and improvement of the lamp luminous flux maintenance rate, which can also be seen in the above description. Thus, these two issues are considered to be very closely related to each other.

For example, Japanese Patent Application Laid-Open No. 62-229752 discloses a solution to the above problem in which an alumina protective film is provided between glass and a phosphor, and the phosphor coating is sandwiched between the glass and the phosphor. A fluorescent lamp provided with an alumina protective layer to improve the luminous flux deterioration characteristics of the fluorescent lamp is disclosed.

JP-A-8-106883 discloses a fluorescent lamp having a light-transmitting protective film made of a metal oxide of a plurality of mixed fine particles between a glass tube and a phosphor film.

Japanese Patent Application Laid-Open No. 9-199085 describes a fluorescent lamp having a protective layer made of a metal oxide of ultrafine particles of alumina between an inner surface of a container and a phosphor layer.

[0014]

However, Japanese Patent Laid-Open Publication No. Sho 62-229752 specifically discloses only aluminum oxide, and the protective film formed on two portions of the inner surface of the glass and the upper surface of the phosphor. Since the properties of the materials are not specified, and the compositions of the materials are the same, there is a problem that the effect of preventing the deterioration of the luminous flux and the effect of reducing the amount of mercury consumed cannot be maximized.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a fluorescent lamp capable of maximizing the effect of preventing light flux deterioration and the effect of reducing the amount of mercury consumption, and a light source device using the same. With the goal.

[0016]

According to a first aspect of the present invention, there is provided a fluorescent lamp including a light-transmitting airtight container in which a discharge medium containing at least mercury is sealed. A phosphor coating is formed on the inner surface side of the hermetic container, and metal oxides other than the phosphor particles are formed between the inner surface of the translucent airtight container and the phosphor coating and on both portions of the phosphor coating on the hermetic space side surface. The metal oxides forming the respective protective layers have different starting materials and have the same chemical composition of the final product.

In this fluorescent lamp, the respective metal oxides disposed at the above-mentioned two parts exhibit a barrier function of minimizing various damages which cause mercury adsorption or light flux deterioration. The effect of preventing luminous flux deterioration and the effect of reducing the amount of mercury consumption can be maximized.

According to a second aspect of the present invention, there is provided a fluorescent lamp including a light-transmitting airtight container in which a discharge medium containing at least mercury is sealed, and a phosphor film is formed on an inner surface side of the light-transmitting airtight container. A protective layer formed of a metal oxide other than the phosphor particles is provided between the inner surface of the translucent airtight container and the phosphor coating, and at both sites on the airtight space side surface of the phosphor coating, The metal oxide forming each protective layer is a metal oxide having a different starting material and a different chemical composition of a final product.

In this fluorescent lamp, the respective metal oxides disposed at the above-mentioned two sites exhibit a barrier function of minimizing various damages which cause mercury adsorption or light flux deterioration. The effect of preventing luminous flux deterioration and the effect of reducing the amount of mercury consumption can be maximized.

The one and the other starting materials of the two protective layers may be composed of a continuum of a fine metal oxide and a metal oxide formed by a sol-gel method, respectively. According to this structure, the luminous flux deterioration preventing effect and the effect of reducing the amount of mercury consumption can be maximized as a whole.

Further, a metal oxide other than the phosphor particles may be interposed at the site in the phosphor coating. With this structure, the effect of preventing the deterioration of the luminous flux and the effect of reducing the amount of mercury consumed can be maximized as a whole.

According to a fifth aspect of the present invention, there is provided a light source device, comprising: the fluorescent lamp; and energy supply means disposed inside or outside the translucent airtight container to supply energy to the discharge medium. And a lighting device for lighting the fluorescent lamp via the energy supply means.

According to this configuration, the effect of preventing the luminous flux from deteriorating and the effect of reducing the amount of mercury consumed can be maximized.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION In extracting the solution to the above-mentioned problem, the inventors of the present invention have stated that, as described above, mercury consumption in a tube does not occur uniformly in all regions in a fluorescent film, or Various experimental studies were conducted based on the hypothesis that the light flux deterioration has many factors and does not occur uniformly in all regions in the fluorescent film. More specifically, since the phosphor film usually has a thickness of several tens of μm, focusing on the portion in the film thickness direction, first, the adhesion of mercury and the phosphor due to ions such as mercury and a rare gas. Degradation of the phosphor due to ion bombardment or ultraviolet rays is most likely to occur on the discharge plasma side, which is the source of the bombardment, and the reaction between the alkali component contained in the glass bulb and mercury is reversed on the inner side of the glass bulb (fluorescent film). Near the boundary with the inner surface of the glass). According to this hypothesis, the metal oxide used as the protective layer is expected to exhibit different effects depending on the thickness direction of the phosphor film. A comparison was made for each site.

As a result, a clear effect difference was found for each application site of various oxides, and surprisingly, it became clear that the difference was larger than expected.

The present invention has been obtained based on this result. As in the prior art, a protective material made of a single or plural kinds of metal oxides is provided in the phosphor coating over the entire area of the phosphor coating. Unlike those that are evenly distributed and interposed,
As the metal oxide, the starting material at the time of its introduction (or the accompanying introduction process) is different, the chemical composition of the final product is the same or different from each other, and the inner surface of the glass bulb and the phosphor coating are used. And one and the other of the two portions of the phosphor coating on the airtight space side surface are respectively composed of a continuum of fine metal oxide and a metal oxide formed by a sol-gel method. That is, the present invention is characterized in that a suitable material and a suitable metal oxide are disposed in a fluorescent lamp. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a partial sectional view of a fluorescent lamp according to a first embodiment of the present invention, FIG. 2 is a view showing an example of a light source device using the present fluorescent lamp, and FIG. 3 is a light source using the present fluorescent lamp. The figure shows another example of the apparatus, and the fluorescent lamp will be described with reference to these figures. However, the basic structure of the fluorescent lamp of the present invention is applicable to any of the translucent airtight containers of the electrodeed fluorescent lamp shown in FIG. 2 and the electrodeless fluorescent lamp shown in FIG. The following description is made using the same reference numeral 1 for the container for convenience.

The light source device of the electrodeed fluorescent lamp shown in FIG. 2 comprises a light-transmitting airtight container (glass bulb) 1 made of glass in which a discharge medium containing mercury vapor and a rare gas is sealed, and discharge of the discharge medium. And a pair of internal electrodes (energy supply means) 2a provided inside the translucent airtight container 1 for starting and maintaining the operation, and supplying power from the power supply 3 to supply power to the pair of internal electrodes 2a. And the device 4a. On the other hand, the light source device of the electrodeless fluorescent lamp shown in FIG. 3 has a light-transmitting airtight container 1 made of glass in which a discharge medium containing mercury vapor and a rare gas is sealed, and for starting and maintaining discharge of the discharge medium. The light-transmitting airtight container 1 is provided with an induction coil (energy supply means) 2b provided outside the light-tight airtight container 1 and a lighting device 4b which receives power from the power supply 3 and supplies power to the induction coil 2b. The fluorescent lamps shown in FIGS. 2 and 3 have a phosphor coating 5 formed on the inner surface side of each translucent airtight container 1 and have the following structure.

That is, as shown in FIG. 1, the fluorescent lamp includes a light-transmitting airtight container 1 in which a discharge medium containing at least mercury is sealed, and an inner surface of the light-transmitting airtight container 1 (where discharge plasma is generated). The phosphor film 5 is formed on the airtight space side of the phosphor), and the phosphor film 5 is composed of phosphor particles 50. Further, a glass protective film 11 is formed between the inner surface of the translucent airtight container 1 and the phosphor coating 5, while an airtight space of the phosphor coating 5 (discharge plasma in FIG. 1).
A surface protection layer 12 is formed on the side surface. The glass protective film 11 and the surface protective layer 12 are formed of the phosphor particles 50.
The starting materials at the time of introduction (or the accompanying introduction process) are different, and the chemical composition of the final product is constituted by the same metal oxide.

Here, in the fluorescent lamp manufacturing process, focusing only on the process of forming the phosphor film, the phosphor powder as a product is usually suspended in water or an organic solvent together with an additive such as a suitable binder. This is formed as a coating liquid (phosphor slurry) after flowing into or spraying into the inner surface of the lamp bulb, followed by a drying and firing step. Therefore, as a means for introducing a metal oxide (other than the phosphor particles) into the phosphor coating of the final lamp finished product as in the present embodiment, a method using existing metal oxide fine particles and a sol-gel method are used. There are two methods.

In the method using the existing metal oxide fine particles, the fine particles are preliminarily coated on the surface of the fluorescent powder, and the fine particles are then suspended in water or an organic solvent. ), Or a method of simultaneously dispersing and suspending the phosphor powder and the metal oxide during the preparation of the phosphor slurry.

In the sol-gel method, a solution (sol) of an inorganic salt of a metal element constituting a metal oxide to be finally formed or a solution (sol) of an organic compound of a similar metal element (metal alkoxide) is used. After dispersing the phosphor particles, a desired metal oxide film is formed on the surface of the phosphor particles by a hydrolysis reaction in a drying / firing step, and the phosphor is converted into a phosphor slurry or, usually, by this method. After a phosphor film is formed on the bulb, this sol solution is infiltrated from above, and a desired metal oxide is formed in the phosphor film by a hydrolysis reaction by the same heat treatment. is there.

Returning to FIG. 1, the starting material, that is, the phosphor particles other than the phosphor particles provided on both the inner surface of the translucent airtight container 1 and the phosphor coating 5 and on both surfaces of the phosphor coating 5 on the airtight space side The starting material (or the accompanying introduction process) relating to the metal oxide of the above is a fine particle material already having a composition as a metal oxide as described in the above-mentioned method using the existing metal oxide fine particles and the sol-gel method, or It means any sol solution of a metal compound that is not originally an oxide.

That is, a metal oxide of fine particles is applied to the glass protective film 11, and a continuum of a metal oxide formed by a sol-gel method is applied to the surface protective layer 12 by a sol-gel method. A continuum of metal oxide formed by the sol-gel method is applied to each region in the fluorescent lamp by adding a protective material having the same material composition as the fine metal oxide to the surface protective layer 12 in the fluorescent lamp. Each metal oxide provided has a barrier function that minimizes various types of damage that cause adsorption of mercury or deterioration of luminous flux, and as a whole, the effect of preventing luminous flux deterioration and reducing the amount of mercury consumed is maximized. Will be withdrawn. A continuum is a relatively dense aggregate formed by a sol-gel-based starting material, compared to an aggregate in the case of using a fine-particle-based starting material or a material having voids between fine particles such as a coating layer. Body or covering layer.

As described above, according to the first embodiment, the effect of preventing luminous flux deterioration and the effect of reducing the amount of mercury consumed can be maximized.

The above-described fluorescent lamp is not limited to the fluorescent lamp shown in FIGS. 2 and 3, but may be of various types. It is also applicable to a type in which a conductor foil is brought close to the coil instead of the coil.

FIG. 4 is a partial cross-sectional view of a fluorescent lamp according to a second embodiment of the present invention. The second embodiment will be described below with reference to FIG.

This fluorescent lamp is similar to the first embodiment,
A light-transmitting airtight container 1 in which a discharge medium containing at least mercury is sealed is provided, and a phosphor film 5 is formed on an inner surface side (airtight space side where discharge plasma is generated) of the light-transmitting airtight container 1. This phosphor coating 5 is composed of phosphor particles 50.

A glass protective film 21 is formed between the inner surface of the translucent airtight container 1 and the phosphor film 5, while a surface protective layer 22 is formed on the surface of the phosphor film 5 on the airtight space side.
Are formed. The glass protective film 21 and the surface protective layer 22 are metal oxides other than the phosphor particles 50, and have different starting materials (or accompanying introduction processes) at the time of their introduction and different chemical compositions of final products. It is composed of a metal oxide.

That is, one of the glass protective film 21 and the surface protective layer 22 is made of a fine metal oxide having a primary particle diameter of 1 μm or less, and the other is formed by a sol-gel method containing a metal element. It is made of a metal oxide that is finally made into a continuum. More specifically, a metal oxide of fine particles is applied to the glass protective film 21, a protective material having a material composition different from a continuum of a metal oxide formed by a sol-gel method is applied to the surface protective layer 22, or a sol-gel is applied to the glass protective film 21. A continuum of metal oxide formed by the method is formed by adding a protective material having a different material composition to the surface protective layer 22 with a fine particle metal oxide in a fluorescent lamp.

As described above, according to the second embodiment, each metal oxide disposed in each region in the fluorescent lamp has a barrier function of minimizing various types of damage which cause adsorption of mercury or deterioration of light flux. As a whole, the effect of preventing luminous flux deterioration and the effect of reducing the amount of mercury consumed can be maximized.

FIG. 5 is a partial sectional view of a fluorescent lamp according to a third embodiment of the present invention, and the third embodiment will be described below with reference to FIG.

This fluorescent lamp is similar to the first embodiment,
A light-transmitting airtight container 1 in which a discharge medium containing at least mercury is sealed is provided, and a phosphor coating 5 is formed on an inner surface side (airtight space side where discharge plasma is generated) of the light-transmitting airtight container 1. The phosphor coating 5 is composed of phosphor particles 50. Further, the inner surface of the translucent airtight container 1 and the phosphor coating 5
While the glass protective film 11 is formed between
A surface protection layer 12 is formed on the surface of the phosphor coating 5 on the airtight space side.

Further, in addition to the structure of the first embodiment, the metal oxide 13 other than the phosphor particles 50 is used in the phosphor particles 50 from the viewpoint of more surely preventing mercury adsorption and various damages to the phosphor particles 50. It has a structure interposed at a site in the coating 5. The metal oxide 13 has the same starting material as one of the glass protective film 11 and the surface protective layer 12,
In other words, the starting material is different from the other of the glass protective film 11 and the surface protective layer 12, and the chemical composition of the final product is the same as both the glass protective film 11 and the surface protective layer 12.

That is, in the third embodiment, in addition to the portions of the glass protective film 11 and the surface protective layer 12, a protective material (metal oxide 13) is formed in the portion of the phosphor coating 5, and these three portions are formed. Of these three parts, one or two of these three parts are composed of fine metal oxides, while the remaining parts are composed of metal oxide continuum formed by the sol-gel method. . Note that the presence of the metal oxide 13 at a site in the phosphor coating 5 means that the metal oxide 13 exists in a state where the metal oxide 13 is directly coated on the surface of the phosphor particles 50 or that the metal oxide 13 exists in a gap between the phosphor particles 50. Means at least one of the embodiments.

As described above, according to the third embodiment, each metal oxide disposed in each region in the fluorescent lamp has a barrier function of minimizing various types of damage which cause adsorption of mercury or deterioration of luminous flux. As a whole, the effect of preventing luminous flux deterioration and the effect of reducing the amount of mercury consumed can be maximized.

FIG. 6 is a partial sectional view of a fluorescent lamp according to a fourth embodiment of the present invention, and the fourth embodiment will be described below with reference to FIG.

The present fluorescent lamp is similar to the second embodiment,
A light-transmitting airtight container 1 in which a discharge medium containing at least mercury is sealed is provided, and a phosphor coating 5 is formed on an inner surface side (airtight space side where discharge plasma is generated) of the light-transmitting airtight container 1. The phosphor coating 5 is composed of phosphor particles 50. Further, the inner surface of the translucent airtight container 1 and the phosphor coating 5
While a glass protective film 21 is formed between
A surface protective layer 22 is formed on the surface of the phosphor film 5 on the airtight space side.

Further, in addition to the structure of the second embodiment, the structure is such that the metal oxide 23 other than the phosphor particles 50 is interposed at a site in the phosphor coating 5. The metal oxide 23 has the same starting material as one of the glass protective film 21 and the surface protective layer 22, in other words, the starting material is different from the other of the glass protective film 21 and the surface protective layer 22, and the final product Chemical composition is glass protective film 21 and surface protective layer 2
Different from one of the two.

That is, in the fourth embodiment, in addition to the portions of the glass protective film 21 and the surface protective layer 22, a protective material (metal oxide 23) is formed in the portion of the phosphor coating 5, and these three portions are formed. Has a structure having a metal oxide, and of these three sites, one or two sites have a primary particle diameter of 1 μm.
The remaining portion is made of a metal oxide continuum formed by a sol-gel method containing a metal element, while the remaining portion is made of a metal oxide of fine particles of m or less.

As described above, according to the fourth embodiment, each metal oxide disposed in each region in the fluorescent lamp has a barrier function of minimizing various types of damage that cause adsorption of mercury or deterioration of luminous flux. As a whole, the effect of preventing luminous flux deterioration and the effect of reducing the amount of mercury consumed can be maximized.

[0052]

Embodiments of the present invention will be described below. However, the common lamp specification in the present embodiment is an electrodeless fluorescent lamp using Y ₂ O ₃ : Eu (trivalent europium-activated yttrium oxide) which is a typical rare earth fluorescent material as a fluorescent material. The tube wall load at the time (value obtained by dividing the lamp input by the light emitting area, that is, the coating area of the phosphor coating) is about 150 m.
A lighting experiment was performed at a setting of W / cm ² . Although an embodiment using an electrodeless fluorescent lamp will be described, it is needless to say that the same effect can be obtained by using an electroded fluorescent lamp (a hot cathode type or a cold cathode type does not matter).

First, a preferred embodiment corresponding to the first and second embodiments from the viewpoint of improving the luminous flux maintenance rate with the passage of the lighting time will be described with reference to (Table 1).

[0054]

[Table 1] Table 1 shows the chemical composition of the final product of the glass protective film, the luminous flux maintenance factor, the chemical composition of the final product of the surface protective layer, and the luminous flux maintenance factor for each of Examples 1 to 3 and Conventional Example 1. Is shown. Regarding the luminous flux maintenance factor, the lighting time 100
This is the time required for the luminous flux value to drop to 70% when the luminous flux value in time is 100%, and is shown as a relative value when the luminous flux maintenance factor in the conventional example 1 is 100%. Therefore, it is desirable that the luminous flux maintenance ratio shown in (Table 1) be large.

In Table 1, in the conventional example 1, the glass protective film and the surface protective layer were made of a metal oxide (Y ₂ O ₃ : yttrium oxide) in which the starting material was fine particles and the final product had the same chemical composition. Is formed.

In Examples 1 and 2, the glass protective film and the surface protective layer are formed of metal oxides having different starting materials and the same final composition. That is, in Example 1, the glass protective film was made of fine particles and the chemical composition of the final product was Y ₂ O ₃ , as in Conventional Example 1, but the surface protective layer was a continuous film of the starting material and the final product Has a chemical composition of Y ₂ O ₃ . Further, in the second embodiment,
As in the case of Conventional Example 1, the starting material is fine particles and the chemical composition of the final product is Y ₂ O ₃ , whereas the glass protective film is a continuous film of the starting material and the chemical composition of the final product is Y ₂ , as in Conventional Example 1. It is O ₃ .

In Example 3, the glass protective film and the surface protective layer are formed of metal oxides having different starting materials from each other and different chemical compositions of final products. That is, the starting material of the glass protective film is a continuous film, and the chemical composition of the final product is Al ₂ O ₃ (aluminum oxide). The surface protective layer is composed of fine particles of the starting material and the chemical composition of the final product is Y _2.
O ₃ .

Here, when looking at (Table 1), Examples 1 to 3 are shown.
It can be seen that the effect of preventing light beam deterioration was obtained from the fact that all the light beam maintenance ratios were 100% or more.

Next, a preferred embodiment corresponding to the first and second embodiments from the viewpoint of reducing the amount of mercury consumed in the tube as the lighting time elapses will be described with reference to (Table 2).

[0060]

[Table 2] Table 2 shows the chemical composition of the final product of the glass protective film, the amount of mercury consumed, the chemical composition of the final product of the surface protective layer, and the amount of mercury consumed for Examples 4 to 6 and Conventional Example 2. Is shown. The amount of mercury consumed is shown as a relative value based on data obtained by measuring the amount of mercury consumed in the phosphor coating of the lamp after the lighting test by chemical analysis, with the data in Conventional Example 2 taken as 100%. Have been. Therefore,
The smaller the value of the amount of mercury consumed shown in (Table 2), the more desirable.

In Table 2, in the conventional example 2, the glass protective film and the surface protective layer are formed of a metal oxide Al ₂ O ₃ in which the starting material is fine particles and the final product has the same chemical composition.

In Examples 4 and 5, the glass protective film and the surface protective layer are formed of metal oxides Al ₂ O ₃ having different starting materials and the same final composition. That is, in Example 4, the glass protective film was made of Al ₂ O ₃ having the same chemical composition of the final product as the starting material in the same manner as in Conventional Example 2, but the surface protective layer was formed of a continuous film as the starting material. The chemical composition of the product is Al ₂ O ₃ . In Example 5, the surface protective layer was made of fine particles of Al ₂ O ₃ having the same chemical composition as the final product, as in Conventional Example 2, whereas the glass protective film was formed of a continuous film of the final material. The chemical composition of the product is Al ₂ O ₃ .

In Example 6, the glass protective film and the surface protective layer are formed of metal oxides having different starting materials from each other and different chemical compositions of final products. That is, the starting material of the glass protective film is fine particles and the chemical composition of the final product is Al ₂ O _{3. The} surface protective layer is a continuous film of the starting material and the chemical composition of the final product is Y ₂ O ₃ .

Here, looking at (Table 2), Examples 4 to 6 can be seen.
It can be seen that the effect of reducing the amount of mercury consumed was obtained from the fact that the amount of mercury consumed was 100% or less.

From Tables 1 and 2, it can be seen from Tables 1 and 2 that, for the glass protective film and the surface protective layer, metal oxides having different starting materials and the same or different chemical compositions of final products were used. And the other is formed of a continuum of a fine metal oxide and a metal oxide formed by a sol-gel method, respectively, thereby maximizing the effect of preventing luminous flux deterioration and reducing the amount of mercury consumed.

Next, a preferred embodiment corresponding to the third and fourth embodiments from the viewpoint of improving the luminous flux maintenance ratio with the passage of the lighting time will be described with reference to (Table 3).

[0067]

[Table 3] This (Table 3) shows the chemical composition of the final product of the glass protective film, the luminous flux maintenance factor, and the final product of the metal oxide interposed in the phosphor coating for Examples 7 to 10 and Conventional Example 3. The chemical composition, the luminous flux maintenance factor, the chemical composition of the final product of the surface protective layer, and the luminous flux maintenance factor are shown. The luminous flux maintenance factor is shown as a relative value to Conventional Example 3.

In Table 3, in the conventional example 3, the metal oxide in the glass protective film, the surface protective layer, and the phosphor coating was:
In each case, the starting material is fine particles, and the chemical composition of the final product is formed of the same metal oxide Y ₂ O ₃ .

In Examples 7 to 10, the metal oxide in the phosphor coating was the same as the starting material of one of the glass protective film and the surface protective layer, in other words, the other of the glass protective film and the surface protective layer was the same as the starting material. And the chemical composition of the final product is the same as or different from both the glass protective film and the surface protective layer.

That is, in Example 7, the starting material of the metal oxide in the phosphor coating is the same fine particles as the surface protective layer, unlike the continuous film of the glass protective film, and the chemical composition of the final product is the glass protective film. And Y ₂ O ₃ which is the same as both the surface protective layer and the surface protective layer.

In Example 8, the metal oxide in the phosphor coating was a continuous film having the same starting material as the glass protective film except for the fine particles of the surface protective layer. It is the same Y ₂ O ₃ as both of the protective layers.

In the ninth embodiment, the metal oxide in the phosphor coating is a fine particle whose starting material is the same as the glass protective film, unlike the continuous film of the surface protective layer, and the chemical composition of the final product is the glass protective film and the surface. It is the same Y ₂ O ₃ as both of the protective layers.

In Example 10, the metal oxide in the phosphor coating was a continuous film having the same starting material as the glass protective film, unlike the fine particles of the surface protective layer, and the chemical composition of the final product was SiO 2 in the glass protective film. ₂ unlike the surface protective layer is the same Y ₂ O _3.

Here, looking at (Table 3), it can be seen that Examples 7-1
It can be seen that the effect of preventing light beam deterioration was obtained from all the light beam maintenance ratios of 0 being 100% or more.

Next, a preferred embodiment corresponding to the third and fourth embodiments from the viewpoint of reducing the amount of mercury consumed in the tube as the lighting time elapses will be described with reference to (Table 4).

[0076]

[Table 4] This (Table 4) shows the chemical composition of the final product of the glass protective film for each of Examples 11 to 14 and Comparative Example 4,
It shows the amount of mercury consumed, the chemical composition of the final product of the metal oxide interposed in the phosphor coating, the amount of mercury consumed, the chemical composition of the final product of the surface protective layer, and the amount of mercury consumed. The amount of mercury consumed is shown as a relative value to Comparative Example 4.

In Table 4, in Comparative Example 4, the metal oxide in the glass protective film, the surface protective layer, and the phosphor coating were:
In each case, the starting material is fine particles, and the chemical composition of the final product is formed of the same metal oxide Al ₂ O ₃ .

In Examples 11 to 14, the metal oxide in the phosphor coating was the same as the starting material of one of the glass protective film and the surface protective layer, in other words, the other of the glass protective film and the surface protective layer was the same as the starting material. And the chemical composition of the final product is the same as or different from both the glass protective film and the surface protective layer.

That is, in Example 11, the starting material of the metal oxide in the phosphor coating was the same fine particles as the surface protective layer, unlike the continuous film of the glass protective film, and the chemical composition of the final product was the glass protective film. Al _{2 which} is the same as both the surface protection layer
O ₃ .

In Example 12, the metal oxide in the phosphor film was a continuous film having the same starting material as the glass protective film except that the starting material was different from the fine particles of the surface protective layer. The same Al ₂ O ₃ as both of the protective layers.

In the thirteenth embodiment, the metal oxide in the phosphor coating is a fine particle whose starting material is the same as the glass protective film, unlike the continuous film of the surface protective layer, and the chemical composition of the final product is the glass protective film and the surface. The same Al ₂ O ₃ as both of the protective layers.

In Example 14, the metal oxide in the phosphor film is a continuous film having the same starting material as the surface protective layer, unlike the fine particles of the glass protective film, and the final product has a chemical composition of Y in the surface protective layer. ₂ O _3, unlike the same Al ₂ O ₃ and glass protective film.

Here, when looking at (Table 4), Examples 11 to
Since the mercury consumption in all fourteen samples is 100% or less, it can be seen that the effect of reducing the mercury consumption was obtained.

From Tables 3 and 4, it can be seen from Table 3 that, for the glass protective film and the surface protective layer, metal oxides having different starting materials and the same or different chemical compositions of final products were used, By interposing a metal oxide other than the phosphor particles in the body coating, it is possible to maximize the effect of preventing luminous flux deterioration and the effect of reducing the amount of mercury consumed.

[0085]

As is apparent from the above description, according to the first to fifth aspects of the present invention, it is possible to maximize the effect of preventing luminous flux deterioration and the effect of reducing the amount of mercury consumed.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of a fluorescent lamp according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of a light source device using the present fluorescent lamp.

FIG. 3 is a diagram showing another example of a light source device using the present fluorescent lamp.

FIG. 4 is a partial cross-sectional view of a fluorescent lamp according to a second embodiment of the present invention.

FIG. 5 is a partial sectional view of a fluorescent lamp according to a third embodiment of the present invention.

FIG. 6 is a partial sectional view of a fluorescent lamp according to a fourth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Translucent airtight container 2a Internal electrode 2b Induction coil 3 Power supply 4a, 4b Lighting device 5 Phosphor coating 50 Phosphor particle 11, 21, Glass protective film 12, 22, Surface protective layer 13, 23 Metal oxide

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masahiro Higashikawa 1048 Kadoma, Kadoma, Osaka Pref. Matsushita Electric Works Co., Ltd. F-term (reference)

Claims (5)

[Claims] 1. A light-transmitting airtight container in which a discharge medium containing at least mercury is enclosed, a phosphor film is formed on an inner surface side of the light-transmitting airtight container, and the light-transmitting airtight container has an inner surface and a light-transmitting airtight container. A metal oxide layer comprising a protective layer formed of a metal oxide other than phosphor particles is provided between the phosphor coatings and on both sides of the airtight space side surface of the phosphor coating. Is a fluorescent lamp, characterized in that the starting materials are different from each other and the chemical composition of the final product is the same metal oxide. 2. A light-transmitting airtight container in which a discharge medium containing at least mercury is enclosed, a phosphor film is formed on an inner surface side of the light-transmitting airtight container, and the light-transmitting airtight container has an inner surface and a light-transmitting airtight container. A metal oxide layer comprising a protective layer formed of a metal oxide other than phosphor particles is provided between the phosphor coatings and on both sides of the airtight space side surface of the phosphor coating. Is a metal oxide having a different starting material and a different chemical composition of a final product. 3. The method according to claim 1, wherein one and the other of the starting materials of the two protective layers are respectively a fine particle metal oxide and a continuum of a metal oxide formed by a sol-gel method. The fluorescent lamp as described. 4. The phosphor coating according to claim 1, wherein a metal oxide other than the phosphor particles is interposed at a site in the phosphor coating.
The fluorescent lamp as described. 5. The fluorescent lamp according to claim 1, which is provided inside or outside said translucent airtight container to supply energy to said discharge medium. A light source device comprising: a supply unit; and a lighting device for lighting the fluorescent lamp via the energy supply unit.