JP2003272557A - Glass composition, protective layer composition, binder composition, glass tube for fluorescent lamp, fluorescent lamp, outer tube for high-luminance discharge lamp and high-luminance discharge lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve luminous efficiency of a lamp, in a lamp such as a phosphor lamp and an HID. <P>SOLUTION: This glass composition of a glass tube 11 is similar to that of general soda glass in its basic composition and contains, in addition to the basic composition, a first rare-earth oxide selected from a first group comprising gadolinium oxide (Gd2O3), terbium oxide (Tb2O3) and praseodymium oxide (Pr2O3), and a second rare-earth oxide selected from a second group comprising europium oxide (Eu2O3), terbium oxide (Tb2O3), dysprosium oxide (Dy2O3) and neodymium oxide (Nd2O3), respectively in a range of 0.01-30 wt.%. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent lamp and a high intensity discharge lamp (H).
ID)] and other discharge lamps.

[0002]

2. Description of the Related Art Fluorescent lamps and HID are widely known as lamps that emit light with high efficiency. The fluorescent lamp is equipped with an arc tube in which mercury and a rare gas are enclosed and a phosphor is adhered to the inner surface, and by discharging in the arc tube, ultraviolet rays mainly having a wavelength of 254 nm are generated by the excitation radiation of mercury. A luminous flux is obtained by exciting the phosphor with ultraviolet rays and radiating visible light. As a type of this fluorescent lamp, a straight tube type or a ring type has been generally used, but in addition to this, a light bulb type, a compact type and the like have become popular in recent years.

On the other hand, HID is 100 to 1000 kPa.
High-pressure mercury lamp that emits light by discharging in mercury vapor, metal halide lamp that emits light when metal halide dissociates into metal atoms and halogen atoms and discharges visible light at the metal atom with discharge, in sodium vapor Is a general term for high pressure sodium lamps that emit light by being discharged.

[0004]

In such fluorescent lamps and HIDs, it is required that the power consumption is low, the luminous flux is high, and the life is long, as a basic performance. ing. For example, JP-A-11-167 discloses a method for extending the life of a fluorescent lamp.
In the Japanese Patent Publication No. 899, when the conventional soda glass is used, attention is paid to the fact that sodium that is eluted from the glass at the time of manufacturing or lighting the fluorescent lamp reacts with mercury, so that the brightness of the fluorescent lamp is likely to decrease. A technique has been disclosed in which a glass in which alkali is less likely to be eluted than in conventional soda glass is used to suppress a decrease in brightness of a fluorescent lamp.

Further, in order to obtain a high luminous flux with low power consumption in a fluorescent lamp, for example, research has been conducted to further increase the brightness of the phosphor, and the discharge length can be reduced by making the arc tube thin. The development to secure is also done. With such research and development, the performance of fluorescent lamps and HIDs is also increasing. In recent years, however, the demands for these performances are increasing, and in order to meet those demands, further reduction of power consumption and high luminous flux are required. There is a demand for a technology that makes it possible to obtain

The present invention has been made under such a background, and an object thereof is to improve the luminous efficiency of a fluorescent lamp and a lamp which emits light by discharge such as HID.

[0007]

In order to achieve the above object, in the present invention, in a fluorescent lamp, a glass tube used as an arc tube comprises a first group consisting of gadolinium oxide, terbium oxide and praseodymium oxide, and europium oxide. , A terbium oxide, a dysprosium oxide, and a second group consisting of neodymium oxide, and a glass composition containing two or more oxides selected from the second group.

Alternatively, in a fluorescent lamp including an arc tube in which the inner surface of the glass tube is covered with a protective layer containing a metal oxide as a base material, and a phosphor layer is coated on the protective layer, the protective layer is formed of gadolinium oxide. And a protective layer composition containing two or more oxides selected from the first group consisting of terbium oxide and praseodymium oxide and the second group consisting of europium oxide, terbium oxide, dysprosium oxide and neodymium oxide. did.

Alternatively, in a fluorescent lamp having a phosphor layer formed by binding phosphor particles with a binder, a first group consisting of gadolinium oxide, terbium oxide and praseodymium oxide, europium oxide, terbium oxide, The second consisting of dysprosium oxide and neodymium oxide
It was decided to use a binder composition containing two or more kinds of oxides selected from the group.

In the above-mentioned glass composition, protective layer composition or binder composition, the contents of oxides selected from the first group and oxides selected from the second group are each 0. ．
It is desirable to set it within the range of 01 to 30 wt%.
According to the above-mentioned fluorescent lamp of the present invention, not only the ultraviolet rays having a wavelength of 254 nm generated by the discharge in the mercury vapor in the arc tube are converted into visible light in the phosphor layer, but also the glass tube or the protective layer or The first rare earth oxide and the second rare earth oxide contained in the binder are irradiated, and the ultraviolet rays are efficiently converted into visible light by the first rare earth oxide and the second rare earth oxide.

Here, it is considered that the reason why the light is converted into visible light with high efficiency is that the first rare earth oxide and the second rare earth oxide work together in the following manner. The first rare earth oxide is excited by ultraviolet light having a wavelength of 254 nm and emits near ultraviolet light having a longer wavelength. Meanwhile, the second
The rare earth oxide also has a function of converting ultraviolet light having a wavelength of 254 nm into visible light, but also converts near-ultraviolet light having a long wavelength emitted from the first rare earth oxide into visible light.

That is, the first rare earth oxide has a wavelength of 254.
nm ultraviolet rays are converted into near ultraviolet rays and transmitted to the second rare earth oxide, and this intermediate action causes the ultraviolet rays of wavelength 254 nm to be directly converted into visible light by the second rare earth oxide. It is considered that the light is converted into visible light more efficiently than in the case of conversion. In addition, near-ultraviolet rays emitted from the first rare earth oxide are not emitted to the outside of the arc tube, and thus are referred to as harmful ultraviolet rays 380.
The following radiation energy nm 0.02μW / cm ^2/1
It is also possible to suppress it to 000 lx or less.

In HID, the outer tube is selected from the first group consisting of gadolinium oxide, terbium oxide and praseodymium oxide, and the second group consisting of europium oxide, terbium oxide, dysprosium oxide and neodymium oxide. It was decided to form the glass composition containing at least one kind of oxide. Also by this, as in the case of the fluorescent lamp, the ultraviolet rays from the arc tube are efficiently converted into visible light by the first rare earth oxide and the second rare earth oxide.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] FIG. 1 is a diagram showing a straight tube fluorescent lamp according to the present embodiment. Figure 2
It is a schematic diagram which shows the light emission mechanism in this fluorescent lamp. As shown in FIG. 1, the fluorescent tube 10 is composed of a cylindrical glass tube 11 to which bases 16 are fixed.

As shown in the cross section of FIG. 1, the glass tube 1
A protective layer 12 is formed on the inner surface of No. 1 and a phosphor layer 13 is formed thereon. The discharge space 14 inside the phosphor layer 13 is filled with a rare gas such as argon and mercury. The filling pressure is, for example, 2 to 4 hPa
Is. The glass tube 11 is made of a material based on soda glass, but contains a rare earth oxide described later.

The protective layer 12 is made of SiO.₂, Α-Al₂O₃,
γ-Al₂O₃, TiO₂, ZnO, B ₂O₃, Sc₂O₃,
Y₂O₃, MgO, Cs₂Main component is oxide selected from O
Which is a layer to be eluted and which is eluted from the glass tube 11
Mercury (Na) enclosed in the discharge space 14 (H
g) to increase the luminous flux maintenance factor by preventing contact with
Perform a function. The thickness of the protective layer 12 is 0.01 to 1
μm is suitable.

The phosphor layer 13 is a layer in which phosphor particles of a three-wavelength band emission type are bound by a binder and are formed on the protective layer 12. Electrodes 15 are provided at both ends of the discharge space 14. The electrode 15 is a coil-shaped filament coated with an emitter (electron emitting substance), the right side of which is a cathode and the left side of which is an anode (not shown in FIG. 1). Are fixed by the electrode glass 17.

(Regarding the glass composition used for the glass tube 11) The basic composition of the glass composition used for the glass tube 11 is the same as that of general soda glass and is as follows. _{SiO 2: 60~75wt% Al 2 O} 3: 1~5wt% B 2 O 3: 0~5wt% R 2 O: 3~30wt% ( where, R = Li, Na, 1 or more selected from K Element) R'O: 3 to 20 wt% (however, R '= Mg, Ca, S
One or more elements selected from r, Ba, and Zn) The reason for defining the range of each component in this way is as follows.

Since SiO ₂ is a component which forms the skeleton of glass, it is better that its content is basically high, and 60 w
If it is less than t%, electrical resistance and workability are deteriorated, which is not preferable. On the other hand, if it exceeds 75 wt%, the softening temperature of the glass becomes too high, making molding difficult and making the thermal expansion coefficient too small. Al ₂ O ₃ has a content of 1 w
If it is less than t%, the chemical durability is lowered. On the other hand, when the content exceeds 5 wt%, the glass becomes non-uniform and striae increase.

B ₂ O ₃ is an optional component, but when added in a small amount, it has the effects of increasing strength and durability and suppressing devitrification. On the other hand, when the content exceeds 5 wt%, the expansion coefficient becomes too small. When R ₂ O is contained in an amount of 3 wt% or more, the so-called alkali mixing effect is obtained and the raw material cost is reduced. However, the content is 30w
If it exceeds t%, the coefficient of thermal expansion becomes too large.

When R'O is contained in an amount of 3 wt% or more, the hardness, electrical insulation and chemical durability of glass are improved. However, if the content exceeds 20 wt%, the glass tends to be devitrified. However, in addition to the basic composition described above, the glass composition of the glass tube 11 in the present embodiment is
Gadolinium oxide (Gd ₂ O ₃ ), terbium oxide (Tb
₂ O ₃ ) and praseodymium oxide (Pr ₂ O ₃ ) first
A first rare earth oxide selected from the group, europium oxide (Eu ₂ O ₃ ), terbium oxide (Tb ₂ O ₃ ), dysprosium oxide (Dy ₂ O ₃ ), and neodymium oxide (Nd ₂₎
The second rare earth oxide selected from the second group consisting of O ₃ ) is contained in the range of 0.01 to 30 wt%, respectively.

Gd mentioned above as the first rare earth oxide
₂ O ₃ , Tb ₂ O ₃ , and Pr ₂ O ₃ have the property of being excited by ultraviolet rays having a wavelength of 254 nm and emitting near ultraviolet rays having a longer wavelength. On the other hand, E mentioned as the second rare earth oxide
u ₂ O ₃ , Tb ₂ O ₃ , Dy ₂ O ₃ , and Nd ₂ O ₃ have the property of being excited by ultraviolet rays and emitting visible light.

Tb₂O₃Combines both of the above properties
Since it is included in both the first group and the second group,
Both as the first rare earth oxide and the second rare earth oxide
Tb ₂O₃Shall not be selected. like this
The glass composition used for the simple glass tube 11 is ordinary soda.
Before melting the glass material, add the rare earth oxide powder
Made by adding, dissolving and molding this mixture
can do.

(Function and Effect of Using the Glass Composition in the Glass Tube 11) FIG. 2 is a diagram for explaining the light emitting mechanism of the fluorescent lamp. In the fluorescent lamp of the present embodiment, the main mechanism of generating the luminous flux is the same as that of the conventional fluorescent lamp. That is, when a voltage is applied to the electrode of the fluorescent tube 10 by the lighting circuit, a discharge is generated in the discharge space inside the fluorescent tube 10, and mercury and a rare gas are excited inside the fluorescent tube 10 with the discharge. Ultraviolet rays UV1 (main wavelength 254 nm) are generated. Then, when the generated ultraviolet rays UV1 are applied to the phosphor layer 13, the phosphor particles are excited to generate visible light V1 (wavelength of about 400 nm or more). This visible light V1 passes through the glass tube 11 and is emitted to the outside, and becomes the main luminous flux of the fluorescent tube 10.

In the fluorescent lamp of the present embodiment, in addition to the main luminous flux, a secondary luminous flux (visible light V2) is generated as follows. A part of the ultraviolet rays UV1 generated in the fluorescent tube 10 passes through the fluorescent layer 13 and is applied to the glass tube 11. The glass tube 11 contains the above-mentioned first and second rare earth oxides. Therefore, when these rare earth oxides are excited by the ultraviolet rays UV1, visible light V2 is emitted from the glass tube 11.

That is, in the fluorescent lamp of the present embodiment, not only the main luminous flux (visible light V1) but also the secondary light emission due to the first and second rare earth oxides contained in the glass tube 11 are emitted. A luminous flux (visible light V2) is also generated, so that the luminous efficiency is improved accordingly. In particular, high luminous efficiency can be obtained by including the first rare earth oxide and the second rare earth oxide. It is considered that the 254 nm ultraviolet ray is converted into visible light with high efficiency by the synergistic action of the rare earth oxide of 2.

The first rare earth oxide is excited by ultraviolet rays having a wavelength of 254 nm to generate near-ultraviolet rays (G) having a longer wavelength.
In the case of d ₂ O ₃ , the wavelength is about 315 nm). On the other hand, the second rare earth oxides in the case of being excited by ultraviolet rays of wavelength 254nm visible light (Eu ₂ O _3, wavelength 61
However, it is also excited by the near-ultraviolet light emitted from the first rare earth oxide to emit visible light.

Due to the cooperative action of the first rare earth oxide and the second rare earth oxide as described above, the ultraviolet light having a wavelength of 254 nm is more efficiently visible light than the case where the second rare earth oxide is used alone. Is converted to. Further, the near-ultraviolet light emitted from the first rare earth oxide is absorbed by the second rare earth oxide and is used, so that it is not emitted to the outside of the arc tube.

Therefore, when the first rare earth oxide and the second rare earth oxide are contained, the visible light becomes more visible than when only the first rare earth oxide or the second rare earth oxide is contained. The conversion efficiency of is large. In other words, by containing the first rare earth oxide and the second rare earth oxide, compared with the case of containing only the first rare earth oxide or only the second rare earth oxide, Same visible light V2 even if the content is set low
Can be obtained.

When Eu ₂ O ₃ and Gd ₂ O ₃ are contained, the following effects are also obtained. When the glass composition contains only Eu ₂ O ₃ , for example, the glass is colored pink, but when Eu ₂ O ₃ and Gd ₂ O ₃ are contained,
Even if the amount of Eu ₂ O ₃ added is considerably lowered, the same visible light V2
Therefore, it is possible to obtain high conversion efficiency into visible light while suppressing coloring of the glass.

The content of each of the first rare earth oxide and the second rare earth oxide contained in the glass composition should be set within the range of 0.01 to 30 wt% for high visible light conversion. It is preferable in obtaining the rate. This is because when the content of the rare earth oxide is less than 0.01 wt%, the concentration is too low to obtain a sufficient amount of visible light, while when the content of the rare earth oxide exceeds 30 wt%, the rare earth oxide is oxidized. This is because it becomes difficult for the objects to emit energy by exchanging energy with each other (concentration quenching).

By the way, Japanese light bulb industry standard JEL601
According to the general rules for safety confirmation tests for light source products specified in
And the harmful ultraviolet radiation amount of 380 nm or less is 0.1 μW /
cm ²/ 1000 lx or less
It On the other hand, in the fluorescent lamp of the present embodiment,
Near ultraviolet light is absorbed by the second rare earth oxide like
Therefore, as shown in the examples below, 380 nm or less
Lower UV radiation energy is 0.02μW / cm²/ 1
It can be kept as low as 000 lx or less. [Examples] Based on the above-described embodiment,
A 20 W straight tube fluorescent lamp was manufactured.

In Examples 1, 2 and 6, Gd ₂ O ₃ was used as the first rare earth oxide and Tb ₂ O ₃ was used as the second rare earth oxide.
A glass tube was produced using the glass composition containing the. In Example 2, the content of Gd ₂ O ₃ is set to be larger than that in Example 1, and in Example 6, the content of Tb ₂ O ₃ is set to be smaller than that in Example 1. In Example 3, G was used as the first rare earth oxide in the glass tube material.
d ₂ O ₃ contains Eu ₂ O ₃ as the second rare earth oxide.

In Example 4, the glass tube material contains Gd ₂ O ₃ as the first rare earth oxide and Dy ₂ O ₃ as the second rare earth oxide. In Example 5, the glass tube material contains Pr ₂ O ₃ as the first rare earth oxide and Tb ₂ O ₃ as the second rare earth oxide. Also,
Fluorescent lamps according to Comparative Examples 1 and 2 were also produced in the same manner as the example except for the composition of the glass tube.

In Comparative Example 1, the glass tube material contains no rare earth oxide. In Comparative Examples 2, 3 and 4, the glass tube material contains only Tb ₂ O ₃ as a rare earth oxide.

[0036]

[Table 1] The glass tube compositions of the fluorescent lamps according to Examples 1 to 6 and Comparative Examples 1 to 4 are as shown in Table 1. The glass composition used for each glass tube was prepared by charging glass raw materials having the composition shown in Table 1 into a platinum crucible, heating and melting at 1500 ° C. for 3 hours, pouring out into a mold, and allowing to cool. .

Properties of each glass composition: The coefficient of thermal expansion α, the glass transition temperature, the softening temperature, the working temperature and the amount of alkali elution were measured for each glass composition according to the examples and comparative examples. The results are also shown in Table 1. The thermal expansion coefficient α was measured at a measurement temperature of 30 to 380 ° C. based on the measuring method specified in JIS R3102.

The glass transition temperature was also measured according to the measuring method specified in JIS R3102. The softening temperature was measured based on the measuring method specified in JIS R3104. The working temperature was measured by reading the temperature at which the viscosity reached 10 ³ P · S from the high temperature viscosity curve.

The amount of alkali elution was measured according to the measuring method specified in JIS R3502. From these measurement results, it can be seen that the glass compositions of both Examples and Comparative Examples are suitable as materials for glass tubes. Emission characteristics of glass composition: The emission spectra of the glass compositions used in the glass tubes of Examples 1 and 2 and Comparative Example 2 when irradiated with ultraviolet light of 254 nm were measured.

The measuring method was as follows. For each glass composition, a test piece having a thickness of 2 mm and a side length of 20 mm was prepared, and excitation light of 254 nm was incident on the test piece at an incident radiation intensity of 0.4 mW / cm ^2. The emission spectrum from the test piece was measured by an instantaneous spectroscope while irradiating so that
3A to 3C show the measurement results,
Is an emission spectrum according to Example 1, (B) is an emission spectrum according to Example 2, and (C) is an emission spectrum according to Comparative Example 2.

In the emission spectra of Example 1 and Example 2, the emission intensities of visible light are almost the same, and slight emission is observed in the near ultraviolet region. On the other hand, in the emission spectrum of Comparative Example 2, the emission intensity of visible light is
It can be seen that it is lower than Measurement of luminous flux value: An initial luminous flux value was measured for each fluorescent lamp according to the example and the comparative example. The results are also shown in Table 1. The initial luminous flux value is a value obtained by measuring the luminous flux of the fluorescent lamp when the life test was performed for 100 hours.

Consideration: Comparing each initial luminous flux value shown in Table 1, in Comparative Example 2 containing Tb ₂ O ₃ ,
Although the luminous flux value is higher than that of Comparative Example 1, Example 1
In all of 6 to 6, higher luminous flux values are obtained as compared with Comparative Example 2. In addition, Gd ₂ O ₃ and Tb are added to the glass tube.
Examples 1, 2 and 6 containing ₂ O ₃ and T in glass tubes
Higher luminous flux values are obtained in Examples 1, 2 and 6 as compared with Comparative Examples 2 to 4 in which only b ₂ O ₃ is contained.

In particular, comparing Example 6 with Comparative Examples 2 and 3, the content of rare earth oxides is the same or lower in Example 6, but a higher luminous flux value is obtained in Example 6. You can see that These results support that the inclusion of the first rare earth oxide and the second rare earth oxide in combination provides higher luminous efficiency than the case of containing only the second rare earth oxide. .

Incidentally, comparing Example 1 and Example 2,
A slightly higher luminous flux value is obtained in the second embodiment. This is considered to be because the content of Gd ₂ O _{3 in} Example 2 was higher. However, in terms of cost, Example 1 having a smaller Gd ₂ O ₃ content is more advantageous. Further, in Comparative Example 4, the luminous flux value is lower than in Comparative Examples 1 to ₃ , but it is considered that this is because the concentration quenching occurs due to the too high concentration of Tb ₂ O ₃ .

Measurement of harmful ultraviolet rays: For each fluorescent lamp according to Examples and Comparative Examples, JEL6 of Japanese Light Bulb Industry Standard
The harmful ultraviolet rays were measured based on the general rule for safety confirmation test of light source products defined in 01. The results are also shown in Table 1. 0.1 μ in both the example and the comparative example
W / cm ² / 1000lx are accommodated below, it can be seen that the harmful ultraviolet rays is suppressed lower than the comparative example towards the Examples.

In addition to those shown in Table 1, the first rare earth oxides (Gd ₂ O ₃ , Tb ₂ O ₃ , Pr ₂ O ₃ ) and the second rare earth oxides (Eu ₂ O ₃ , Tb ₂ O ₃ , Dy ₂ O ₃ , N
It was found that when two kinds are arbitrarily selected from d ₂ O ₃ ) and contained in the glass composition, the lamp luminous flux can be improved as compared with the case where the second rare earth oxide is contained alone. [Second Embodiment] In the first embodiment, the glass tube 11 is used.
Although the first rare earth oxide and the second rare earth oxide are contained in combination in the above, in the present embodiment, the protective layer 12 is used.
In addition, the first rare earth oxide and the second rare earth oxide are contained in combination.

The protective layer 12 in this embodiment can be formed by the following method. Base material of the protective layer 12 (SiO ₂ , α-Al ₂ O ₃ , γ-Al ₂ O ₃ , TiO ₂ , Z
nO, B ₂ O ₃ , Sc ₂ O ₃ , Y ₂ O ₃ , MgO, Cs ₂ O) is used as a powder raw material, and the first rare earth oxide and the second rare earth oxide are added to the powder raw material. A powder of a complex oxide is prepared by adding, melting and crushing, and the powder is added to a solvent such as water or an organic solvent (isopropyl alcohol) together with a dispersant and dispersed therein to prepare a coating solution. To do. Then, this coating solution is applied to the inner surface of the glass tube 11 by a method such as a spraying method,
The protective layer 12 can be formed by drying and baking.

By dissolving the rare earth oxide in the base material in this manner, the base material and the rare earth oxide form a composite oxide. As a method of coating the mixed powder on the inner surface of the glass tube 11, an electrostatic coating method or a sol-gel method using a solution in which a metal alkoxide is dissolved in an organic solvent is used in addition to the wet method as described above. Can also be considered.

According to the above-mentioned protective layer 12, the effect of increasing the luminous flux maintenance factor, which is the original function of the protective layer 12, and the effect of improving the luminous efficiency by the first rare earth oxide and the second rare earth oxide are obtained. be able to. That is, as described in the first embodiment, a part of the 254 nm ultraviolet light generated by the discharge passes through the phosphor layer 13 and is irradiated to the protective layer 12, but it is included in the protective layer 12. By the first rare earth oxide and the second rare earth oxide which are present, the luminous efficiency is improved by being efficiently converted into visible light.

In the protective layer 12, the first and second
Since the rare earth oxide is dissolved in the base material, the protective layer 1
The visible light transmittance of No. 2 is not impaired by the rare earth oxide. Each concentration of the first rare earth oxide and the second rare earth oxide contained in the protective layer 12 is 0.01 to, respectively.
Setting in the range of 30 wt% is preferable in order to obtain a high visible light emission amount.

Not only the protective layer 12 but also the glass tube 1
If 1 also contains the first and second rare earth oxides, not only the first and second rare earth oxides contained in the protective layer 12 but also the rare earth oxides contained in the glass tube 11 are caused. A luminous flux that emits light is also generated, and the luminous efficiency is further improved accordingly. [Third Embodiment] In the first embodiment, the glass tube 11 is used.
Although the first rare earth oxide and the second rare earth oxide are contained in combination in the above, in the present embodiment, the phosphor layer 13 is included.
The first binder and the second rare earth oxide are combined and contained in the above binder.

That is, the phosphor layer in this embodiment has three layers.
Wavelength region emitting phosphor particles are formed by binding with a binder having a mixture of calcium borate / barium and calcium pyrophosphate as a basic material. Then, the first and second rare earth oxides described in the first embodiment are dissolved in the basic material of the binder.

As the basic material of the binder, in addition to the mixture of calcium borate / barium and calcium pyrophosphate, calcium borate / barium or aluminum oxide may be used alone, or a mixture of aluminum oxide and calcium pyrophosphate may be used. You can also In the phosphor layer 13, the addition amount of the binder to the phosphor particles is 0.0
It is preferably set in the range of 01 to 10 wt%.

According to the phosphor layer 13, the ultraviolet rays UV1
When the phosphor layer 13 is irradiated with, the phosphor particles are excited to generate visible light V1, and the visible light V1 becomes the main luminous flux of the fluorescent tube 10, which has been described in the first embodiment. Is the same as. In the present embodiment, further, a part of the ultraviolet rays UV1 generated by the discharge is efficiently converted into visible light by the first rare earth oxide and the second rare earth oxide contained in the binder. Thus, there is an effect that the luminous efficiency is improved.

The respective concentrations of the first rare earth oxide and the second rare earth oxide contained in the binder composition are 0.
It is preferable to set it in the range of 01 to 30 wt% in order to obtain a high visible light conversion rate. The phosphor layer 13 is
It can be manufactured as follows. Mixing the above basic material with the first rare earth oxide and the second rare earth oxide,
A binder is produced by melting and molding this.

The phosphor particles and the above binder are dispersed in a solvent containing a binder to prepare a dispersion liquid. Then, the phosphor layer 13 can be formed by applying the dispersion liquid onto the protective layer 12 of the glass tube 11 and drying and baking. [Embodiment 4] In the present embodiment, the high intensity
The case of applying to a discharge lamp (HID) and an incandescent lamp will be described.

FIG. 4 is a diagram showing an example of a fluorescent mercury lamp. This fluorescent mercury lamp is one type of high-pressure mercury lamp, and as shown in the figure, is composed of an arc tube 51, a base 52, an outer tube 53, and the like. The arc tube 51 is made of transparent quartz glass, has electrodes 54 at both ends, and has mercury and argon gas sealed inside.

The outer tube 53 is formed by coating a phosphor layer 56 on the inner surface of a glass tube 55 provided so as to surround the arc tube 51. In the arc tube 51, visible light is emitted by discharging in mercury vapor of high pressure (100 to 1000 kPa).
In No. 1, ultraviolet light is also emitted, and the phosphor layer 56 of the outer tube 53 receives this ultraviolet light and excites and emits visible light.

Here, the glass tube 55 of the outer tube 53 is made of borosilicate glass, but contains the first rare earth oxide and the second rare earth oxide described in the first embodiment. ing. As a result, the outer tube 53 has the same function and effect as the fluorescent tube 10 described in the first embodiment.

That is, a part of the ultraviolet light from the arc tube 51 is
Although it passes through the phosphor layer 56 and irradiates the glass tube 55,
The first rare earth oxide and the second rare earth oxide contained in the glass tube 55 efficiently convert this ultraviolet light into visible light. Due to this action, the present fluorescent mercury lamp can obtain excellent luminous efficiency. In addition, here, the outer tube 5
Although the fluorescent mercury lamp in which the phosphor layer 56 is provided in 3 is described, even in a high pressure mercury lamp in which the outer tube is not provided with the phosphor layer, the glass composition forming the outer tube has the above-mentioned first rare earth element. By including the oxide and the second rare earth oxide, the luminous efficiency can be improved.

Regarding metal halide lamp and high-pressure sodium lamp: The metal halide lamp is similar to the fluorescent mercury lamp in that it is composed of an arc tube made of transparent quartz glass, an outer tube made of borosilicate glass, etc. In the tube, metal halides such as scandium (Sc) and sodium (N
In addition to (a) the halide), mercury is enclosed as a rare gas for starting and a buffer gas for maintaining an arc discharge at an electrical characteristic and an optimum temperature, and a phosphor layer is provided on the outer tube. Absent.

In such a metal halide lamp, basically, a metal halide is dissociated into a metal atom and a halogen atom along with the discharge in the arc tube, and the metal atom excites and emits visible light to emit light. A luminous flux is obtained. Here, in the arc tube, ultraviolet light is also emitted along with the discharge. Therefore, by including the first rare earth oxide and the second rare earth oxide in the outer tube,
Since ultraviolet rays are efficiently converted into visible light, the total luminous flux is increased and excellent luminous efficiency is obtained.

The high-pressure sodium lamp is composed of an arc tube made of polycrystalline alumina ceramics, an outer tube made of soda glass, and the like. Inside the arc tube, sodium as a luminescent substance, xenon gas as a starting gas, and a buffer gas are provided. Of mercury is enclosed, and the outer tube is not provided with a phosphor layer. Also in such a high-pressure sodium lamp, basically, visible light is excited and radiated to emit a luminous flux with discharge in sodium vapor in the arc tube 71, but a slight amount of ultraviolet light is emitted from the arc tube. Since the outer tube contains the first rare earth oxide and the second rare earth oxide, ultraviolet rays are efficiently converted into visible light, so that the total luminous flux is increased and excellent light emission is achieved. Efficiency is obtained.

Application to incandescent light bulb: Typical incandescent light bulbs are general lighting bulbs and halogen bulbs. A bulb for general lighting is equipped with a bulb made of soft soda glass or hard borosilicate glass, in which an inert gas (nitrogen, argon, krypton, etc.) is sealed, and an introduction wire and an electrode made of a tungsten filament are provided. It is provided.

In a halogen bulb, a bulb made of quartz is generally used, a halogen substance is enclosed together with an inert gas, and an introduction wire and an electrode made of a tungsten filament are provided. In such an incandescent light bulb, basically, as in the conventional case, the filament is heated to energize the electrodes to radiate visible light to obtain a luminous flux. Some are included.

Therefore, by incorporating the first rare earth oxide and the second rare earth oxide similar to those described in the first embodiment into the glass of the bulb material, ultraviolet rays are efficiently converted into visible light. Therefore, the total luminous flux increases,
Excellent luminous efficiency can be obtained.

[0067]

As described above, in the fluorescent lamp of the present invention, gadolinium oxide, terbium oxide and praseodymium oxide are used as the binder for the glass composition, the protective layer composition or the phosphor layer used in the glass tube. A first group consisting of
2 selected from the second group consisting of europium oxide, terbium oxide, dysprosium oxide and neodymium oxide 2
By including at least one kind of oxide, ultraviolet rays are efficiently converted into visible light.

Also in HID, the outer tube was selected from the first group consisting of gadolinium oxide, terbium oxide and praseodymium oxide and the second group consisting of europium oxide, terbium oxide, dysprosium oxide and neodymium oxide. By forming the glass composition containing at least one kind of oxide, ultraviolet rays from the arc tube are similarly efficiently converted into visible light.

[Brief description of drawings]

FIG. 1 is a diagram showing a fluorescent lamp according to a first embodiment.

FIG. 2 is a schematic diagram showing a light emitting mechanism in the fluorescent lamp.

FIG. 3 is an emission spectrum of the glass composition used in the glass tubes of Examples 1 and 2 and Comparative Example 2.

FIG. 4 is a diagram showing a fluorescent mercury lamp according to a third embodiment.

[Explanation of symbols]

10 fluorescent tube 11 glass tubes 12 Protective layer 13 Phosphor layer 14 discharge space 15 electrodes

Continued front page    F-term (reference) 4G062 AA03 BB01 DA06 DA07 DB03                       DC01 DC02 DC03 DD01 DE01                       DE02 DE03 DE04 DF01 EA01                       EA02 EA03 EA04 EA10 EB01                       EB02 EB03 EB04 EC01 EC02                       EC03 EC04 ED01 ED02 ED03                       ED04 EE01 EE02 EE03 EE04                       EF01 EF02 EF03 EF04 EG01                       EG02 EG03 EG04 FA01 FA10                       FB01 FC01 FD01 FE01 FF01                       FG01 FH01 FJ01 FK01 FL01                       GA01 GA10 GB01 GC01 GD01                       GE01 HH01 HH03 HH05 HH07                       HH09 HH11 HH13 HH15 HH17                       HH20 JJ01 JJ03 JJ05 JJ07                       JJ10 KK01 KK02 KK03 KK04                       KK05 KK06 KK07 MM24 NN01                 5C043 AA02 AA03 AA15 CC08 DD02                       DD03 DD29 DD35 EB01 EB08                       EB15

Claims (14)

[Claims] 1. A glass composition used for a glass tube of a fluorescent lamp, the first group consisting of gadolinium oxide, terbium oxide and praseodymium oxide, and the second group consisting of europium oxide, terbium oxide, dysprosium oxide and neodymium oxide. A glass composition comprising at least two oxides selected from each group. 2. The glass composition contains 0.01 to 30 wt% of an oxide selected from the first group and an oxide selected from the second group, respectively. The glass composition according to claim 1. 3. A glass tube for a fluorescent lamp, which is formed of the glass composition according to claim 1. 4. A fluorescent lamp comprising an arc tube in which mercury and a rare gas are enclosed in the glass tube according to claim 3 and a phosphor is adhered to the inner surface thereof, and an electrode for causing discharge in the arc tube. 5. A protective layer composition which is formed on the inner surface of a glass tube of a fluorescent lamp and is used for a protective layer mainly composed of a metal oxide, the first group comprising gadolinium oxide, terbium oxide and praseodymium oxide, Second composed of europium oxide, terbium oxide, dysprosium oxide and neodymium oxide
A protective layer composition comprising two or more oxides selected from the group: 6. The protective layer composition contains 0.01 to 30 wt% of an oxide selected from the first group and an oxide selected from the second group, respectively. The protective layer composition according to claim 5, which is characterized in that. 7. Light emission in which mercury and a noble gas are enclosed in a glass tube whose inner surface is covered with a protective layer comprising the protective layer composition according to claim 5 or 6, and a phosphor is attached to the inner surface. Fluorescent lamp with a tube. 8. A binder composition used for forming a phosphor layer of a fluorescent lamp, the first group consisting of gadolinium oxide, terbium oxide and praseodymium oxide, and europium oxide, terbium oxide, dysprosium oxide. And second consisting of neodymium oxide
A binder composition comprising two or more kinds of oxides selected from the group. 9. The binder composition contains 0.01 to 30 wt% each of an oxide selected from the first group and an oxide selected from the second group. The binder composition according to claim 8. 10. A fluorescent lamp comprising a phosphor layer formed by binding phosphor particles with the binder composition according to claim 8. 11. A glass composition used for an outer tube of a high-intensity discharge lamp, which comprises a first group consisting of gadolinium oxide, terbium oxide and praseodymium oxide, and a first group consisting of europium oxide, terbium oxide, dysprosium oxide and neodymium oxide. Two
A glass composition comprising two or more oxides selected from the group: 12. The glass composition contains 0.01 to 30 wt% of an oxide selected from the first group and an oxide selected from the second group, respectively. The glass composition according to claim 11. 13. An outer tube for a high-intensity discharge lamp, which is formed from the glass composition according to claim 11. 14. A high-intensity discharge lamp in which the outer tube according to claim 13 is provided so as to surround an arc tube which emits visible light and ultraviolet rays in association with discharge.