JPS6183281A - Fluorescent lamp - Google Patents

Abstract

PURPOSE:To provide a high performance fluorescent lamp which does no cause lowering of fluorescence efficiency, off-shade and decrease of flux, prepared by forming a coating layer which transits or reflects visible light and absorbs ultraviolet ray, on the inner surface of a glass tube and applying a specified phosphor over the coating layer. CONSTITUTION:A 1st layer is formed on the inner surface of a glass tube by application of a substance which transmits or reflects visible light and absorbs ultraviolet ray, and a phosphor consisting of a mixt. o phosphor (1) which is a divalent Eu-activated alkaline earth metal halophosphite of the formula (where M is Ba, Ca or Mg/ X is F, Cl or Br; x is 0.01-0.2) having an emission peak at 450-500nm and phosphor (2) having an emission peak at 620-640nm and a half-value range of 120-150mm, is applied to the surface of the 1st layer to form a 2nd layer.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to improvements in fluorescent lamps.

[Technical background of the invention and its problems]

General fluorescent lamps for lighting have a wavelength of 313.3 from the visible wavelength range.
It emits light in a short wavelength range of 390 nm or less, including 65 nm mercury bright line emission. However, 390nm
It is known that the following emission energy fades the colors of various objects. For this reason, anti-fade fluorescent lamps that block short-wavelength emission energy are used for lighting in museums and exhibitions where color is important. As shown in Fig. 2, a general anti-fading type fluorescent lamp has a first layer 2 of a material such as titanium oxide or cerium oxide that absorbs ultraviolet light and reflects visible light on the inner surface of a glass tube 1.
A phosphor, which is a luminescent material, is coated thereon as a second or higher layer 3. In other words, only the first layer 2 absorbs the mercury bright line emission of 313.365 nm and the ultraviolet rays partially emitted from the phosphor layer 3.

However, in conventional anti-fading fluorescent lamps, the first layer absorbs the emitted energy that has passed through the second and higher layers (phosphor layer), so in the case of lamps that use an absorption layer, the emitted light color of the lamp is in the yellow-green direction. In addition, the material used for the first layer, such as titanium oxide, may change color during lighting.
There are problems such as a decrease in luminous flux.

Further, an invention disclosed in Japanese Patent Application Laid-Open No. 102071/1983 is a fluorescent lamp that can provide AAA color rendering while improving the above-mentioned problems. However, in this invention, a large number of 4 types of phosphors with greatly different chromaticity points are mixed, and it is extremely difficult to adjust the chromaticity when manufacturing fluorescent lamps in mass production equipment. The manganese-activated zinc silicate phosphor (ZnSiO4:Mn) deteriorates significantly when lit for a long period of time, resulting in problems such as the color of the lamp light changing during lighting and the luminous flux of the lamp decreasing.

On the other hand, as a color rendering AA type anti-fade fluorescent lamp, titanium oxide is coated as the first layer, and the second layer is coated with 4200k and 6500k antimony- and manganese-activated calcium herophosphate phosphors and magnesium tungstate phosphors. A mixed coating of five types of tin-activated strontium-magnesium phosphate phosphor and manganese-activated magnesium fluorogermanate phosphor is known.

However, similar to the above-mentioned fluorescent lamps, such fluorescent lamps also have problems such as a shift in light color and a decrease in luminous flux.

[Purpose of the invention]

The present invention provides a fluorescent lamp that has color-rendering AAA characteristics by mixing two types of phosphors and minimizes emission energy below 400 nm, and a fluorescent lamp that has color-rendering AA characteristics by mixing three types of phosphors. The objective is to provide a fluorescent lamp that minimizes the emission energy of 400 nm or less.

[Summary of the invention]

As a result of extensive research into the above-mentioned fluorescent lamp, the present inventors have discovered that by mixing only two types of phosphors, the color rendering index is A in the color rendering class defined by JIS Z9112.
We have discovered a fluorescent lamp that has type AA characteristics and can also minimize the amount of ultraviolet absorbing material such as titanium oxide applied.

That is, the invention in Box 1 forms a first layer by coating the inner surface of a glass tube with a substance that transmits or reflects visible light and absorbs ultraviolet rays, and further coats the first layer with a substance that transmits or reflects visible light and absorbs ultraviolet rays. In a fluorescent lamp in which a second or higher layer is formed by coating a phosphor that emits light with
General formula % formula % () [However, M in the formula consists of three types: Ba, Ca, and MO,
3.0-4.5 gram atoms of Ba each.

0.5-2.0 gram atoms of Ca, and 0.01-1.
0 gram atoms (7) MG,) ltF, Cfi.

Br alone or a mixture of two or more, and 0.01
<X≦0.2], 450 to 500n
a first phosphor made of an alkaline earth metal helophosphate activated with divalent europium, which has an emission peak in the wavelength range of 620 to 640 nm; It is characterized by using a mixture of a second phosphor having a half width of ~150 nm.

In addition, as a result of extensive research into the fluorescent lamps mentioned above, the inventors have found that by mixing only three types of phosphors,
We have found a fluorescent lamp that has a color rendering index of type AA in the color rendering index defined by JIS Z9112, and can also minimize the amount of paint of an ultraviolet absorbing substance such as titanium oxide.

That is, the invention in Box 2 forms a first layer by coating the inner surface of a glass tube with a substance that transmits or reflects visible light and absorbs ultraviolet rays, and further coats a substance in the visible wavelength range on the first layer. In a fluorescent lamp in which a second or higher layer is formed by coating a phosphor that emits light with
General formula % formula % () [However, M in the formula consists of three types: Ba, Ca, and MO,
3.0-4.5 gram atoms of Ba each.

0.5-2.0 gram atoms of Ca, and 0.01-1.
has an Mq of 0 gram atom, X is a single substance or a mixture of two or more of F, Ca, and Br, and 0.01<X≦0.
2] and has an emission peak in the wavelength range of 450 to 500 nm and is made of an alkaline earth metal helophosphate activated with divalent europium; A mixture of a second phosphor having an emission peak in a wavelength range of 120 to 150 nm and a third phosphor consisting of an antimony- and manganese-activated calcium fluoroapatite phosphor is used. It is characterized by the fact that

The reason why the content (X) of europium in the general formula of the first phosphor is limited is that if the content is less than 0.01, the brightness of the obtained fluorescent lamp will be significantly reduced. Even if it exceeds 0.2, no improvement in brightness can be achieved. The preferred europium content is 0.03<
X≦0.15. Moreover, the reason for limiting the amount of M in the above general formula is that if the amount of Mo deviates from the above range,
This is because it is not possible to achieve a significant improvement in brightness compared to the case of only Ba and Ca.

The divalent europium-activated alkaline earth metal halophosphate phosphor described above can be easily prepared by the following method. First, after firing treatment, 3a, Ca1M (:l, Zn
, Cd, F, (1, Br, P, and En sources, such as oxides, phosphates, carbonates, ammonium salts, etc.) are weighed in predetermined amounts, and then these raw materials are sufficiently pulverized using, for example, a ball mill. Then, the obtained mixture was placed in an alumina or quartz crucible and heated in air for 80 minutes.
Calcinate at a temperature of 0 to 1200°C for 1 to 5 hours. Thereafter, the fired product is cooled, pulverized, sorted, washed, filtered, dried and sorted to prepare a phosphor.

Furthermore, the divalent europium-activated alkaline earth metal halophosphate phosphor described above functions similarly to titanium oxide, which is used as a conventional ultraviolet absorbing material. This is true for the phosphor shown in FIG. 3, for example (Ba, CaSMG) I (PO4)6 Cff12:
This is clear from the reflection spectra of Eu and titanium oxide.

In addition, A and B in FIG. 3 are (BaSCa, MO)m, respectively.
(PO4)6Cff2: Reflection spectra of Eu and titanium oxide are shown. Moreover, the divalent europium-activated alkaline earth metal halophosphate phosphor reduces harmful ultraviolet radiation, which causes problems in color fading, to about 1/10, even without the use of ultraviolet absorbing substances. can. This is the phosphor shown in FIG. 4, for example (Ba, Ca, MO)I (P○+)scn2 :EL
A sample prepared by applying only I directly to the inner surface of a glass tube,
In the ultraviolet region (this is clear from the spectral distribution of samples similarly prepared using antimony-activated calcium helophosphate and magnesium tungstate, respectively, which are known blue phosphors that exhibit little absorption. A-9 in the diagram
(BaSCa.

MO) Il (PO4)6 Cj22 : These are the spectral distributions of a sample using Eu and a sample using calcium phosphate and magnesium tungstate, respectively, for antimony activation, and HO represents mercury bright line emission.

On the other hand, the above-mentioned divalent europium-activated alkaline earth metal halophosphate phosphor can be modified to have an emission peak wavelength of 450% by changing the compounding ratio of M (Ba, Ca, MO> in the general formula % formula %). ~510nm
It has a wide range of features to choose from.

Examples of the second phosphor include tin-activated strontium magnesium phosphate phosphor.

In the second invention of the present application, the third phosphor that is further blended is one in which chlorine (C2) in the conventionally used antimony and manganese-activated calcium helophosphate phosphor has been completely removed. This has been particularly improved so that the band emission peak wavelength is 570 to 580 nm.

〔Effect of the invention〕

As detailed above, 1. According to the first invention of the present application, the color temperature is increased from about 4000 to 650 by mixing two types of phosphors.
It has the remarkable effect that it is possible to realize an anti-fading type fluorescent lamp having excellent characteristics such as a color rendering index of AAA type in the range of 0. Further, according to the second invention of the present application, by mixing only three types of phosphors, it is possible to realize a fading-resistant fluorescent lance having an excellent color rendering index of AA type. Moreover, according to the present invention, compared to conventional fluorescent lamps, ultraviolet absorbing substances such as titanium oxide, which have a negative effect on the fluorescent lamp characteristics, can be reduced to about 1/6 at the maximum, resulting in a reduction in luminous efficiency. It is possible to provide a high-performance anti-fade fluorescent lamp that hardly causes any shift in light color or decrease in luminous flux during lighting.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail based on Examples and Comparative Examples.

Example 1 In the fluorescent lamp shown in FIG.
) of titanium oxide (first layer) 12 with a tube diameter of 32 (s) 17)
It is coated on the inner surface of the glass tube 11 at a coating amount of 0.28 (mg/ci), and then baked at a predetermined temperature. Next, N in Table 1 below.

Mix phosphors No. 1, No. 1, and No. 4 in a ratio such that the color temperature is 4200 and the deviation is Quv, and coat the mixture (second layer or higher layer) 13 on the first layer 12, A 40 watt type fluorescent lamp having discharge electrodes of 14.degree.

Example 2 Titanium oxide with a particle size of 0.05 (μm) was used as the first layer.
．． No. 35 (rIt9/cd) was coated on the inner surface of the glass tube, and then No. 2 and No. 2 in Table 1 below were applied.

A fluorescent lamp was fabricated as a prototype in the same manner as in Example 1 by mixing the phosphors of No. 4 at a color temperature of 5000 in a ratio such that the deviation was ± Quv, and coating the mixture on the first layer.

Example 3 Titanium oxide with a particle size of 0.06 (μm) was used as the first layer.
40 <m9/cd') on the inner surface of the glass tube, and then the phosphors of Nα3 and Nα4 shown in Table 1 below were mixed in a ratio such that the color temperature was 6500K and the deviation was +0.003UV. The mixture was coated on the first layer, and a fluorescent lamp was fabricated in the same manner as in Example 1.

Comparative Example 1 A fluorescent lamp was experimentally produced in the same manner as in Example 1 using the phosphors of NQ 4 and Nα5 in Table 1 below as the second layer. However, in order to prevent ultraviolet rays from being detected at all, titanium oxide (first layer) must be
It was necessary to apply the coating with a coating amount of 1/ci) or more.

Comparative Example 2 A fluorescent lamp was prototyped by applying only the second layer of the phosphor of Example 2 to the inner surface of a glass tube without applying or adhering titanium oxide.

Therefore, various characteristics of the fluorescent lamps of Examples 1 to 3 and Comparative Examples 1 and 2 were investigated. The results are shown in the second section below.
Shown in the table. However, although not shown in Table 2, no ultraviolet light (300 to 390 nm) was detected during photometry. The spectral distribution of the phosphors No. 1 to No. 5 in Table 1 corresponds to the characteristic line A-E shown in FIG.

In addition, the chromaticity of the fluorescent lamps of Examples 1 to 3 is shown in Fig. 6.
The spectral distributions are shown in FIG. In FIG. 6, a to LC are the chromaticities of Examples 1 to 3, respectively, and la to 1c in FIG. 7 are spectral distribution characteristic lines of Examples 1 to 3, respectively.

As is clear from the above Table 2 and FIGS. 6 and 7, the fluorescent lamp of the present invention has a peak wavelength of divalent europium-activated alkaline earth metal halophosphate phosphor and By appropriately selecting the mixing ratio with the tin-activated strontium-magnesium phosphate phosphor, the color temperature range from 4200K to 6500
It can be seen that a fading-preventing fluorescent lamp having a color rendering class of AAA color rendering class defined by No. 112 can be easily obtained.

Furthermore, by using the europium-activated alkaline earth metal halophosphate phosphor, it is possible to significantly reduce the amount of ultraviolet absorbing substances such as titanium oxide that adversely affect the opening performance of anti-fading fluorescent lamps. This makes it possible to significantly reduce the effects of the ultraviolet absorbing material, such as a decrease in total luminous flux and luminous flux maintenance factor.

Furthermore, the phenomenon that the starting voltage increases, which is a problem when lighting, is about 3 (V) higher for conventional lamps coated with a large amount of titanium oxide than for lamps without titanium oxide coated.
Fluorescent lamps that use much less titanium oxide, such as the present invention, have the problem of a higher starting voltage, as they are almost the same as those that do not have titanium oxide coated on them. We were able to solve it together.

Incidentally, such an effect was also observed when a cerium oxide tetravalent magazine-activated magnesium fluorogermanate phosphor was mixed and used as the ultraviolet absorbing substance.

Example 4 In the fluorescent lamp shown in FIG.
) is coated on the inner surface of a glass tube 11 having a diameter of 32 (M) at a coating amount of 0.28 (my/d), and then baked at a predetermined temperature. Next, the phosphors No. 6, No. 8, and No. 9 in Table 3 below were heated to a color temperature of 5000K.

Mix in a ratio such that the deviation value ○UV, and the mixture (
A 40-watt type fluorescent lamp having discharge electrodes 14 and 15 was fabricated by coating the second or higher layer 13 on top of the first layer 12 according to a conventional manufacturing method.

Example 5 Titanium oxide with a particle size of 0.06 (μm) was mixed with 0.40 (In
After coating the inner surface of the glass tube with a coating amount of 2/cd) and baking, the Nα7°No. shown in Table 3 below was applied.
The phosphors No. 8, No. 8, and No. 9 were mixed at a ratio such that the color temperature was 5,000 K and the deviation was 0.005 uv, and the mixture was coated on the first layer, and the fluorescent material was formed using the same procedure as in Example 4. I made a prototype of a lamp.

Comparative Example 3 Titanium oxide was coated and adhered to the inner surface of a glass tube, and a fluorescent lamp was prototyped in the same manner as in Example 4 using five types of conventional phosphors. In order to prevent ultraviolet rays from being detected at all in this fluorescent lamp, it was necessary to coat titanium oxide in an amount of 1.65 (mfl/c/r) or more.

Comparative Example 4 A fluorescent lamp was prototyped by coating the inner surface of a glass tube using only the second layer of the phosphor of Example 5 without applying titanium oxide.

Therefore, various characteristics of the fluorescent lamps of Example 4.5 and Comparative Example 3.4 were investigated. Its characteristics are explained in the 4th section below.
Shown in the table. However, although not shown in Table 4, when measuring the fluorescent lamps of Examples 4 and 5, ultraviolet rays (300 to 39
0 nm) was not detected at all. In addition, N in Table 3
(The spectral distributions of the phosphors Nos. 16 to 9 are shown in A1.
A2, B.

This is the characteristic line of C.

In addition, the chromaticity of the fluorescent lamp of Example 4.5 is shown in Fig. 9.
The spectral distributions are shown in FIG. 10. la, Lb in Figure 9
are the chromaticities of Examples 4 and 5, respectively, and 1-a and 1 in FIG.
b is the spectral distribution of Example 4.5, respectively.

As is clear from Table 4 and FIGS. 9 and 10 above, the fluorescent lamp of the present invention uses a divalent europium-activated alkaline earth metal helophosphate phosphor in the second and higher layers. It can be seen that a color rendering AA type anti-fade fluorescent lamp can be easily obtained. Furthermore, by using a divalent europium-activated alkaline earth metal helophosphate phosphor, the amount of ultraviolet absorbing substances such as titanium oxide, which adversely affect the opening performance of anti-fade fluorescent lamps, can be significantly reduced. This makes it possible to significantly reduce the effects of ultraviolet absorbing substances, such as reductions in total luminous flux and luminous flux maintenance factor.

Furthermore, the phenomenon of an increase in starting voltage, which becomes a problem when lighting, is that the starting partial pressure of conventional lamps coated with a large amount of titanium oxide is about 3 (V) higher than lamps without titanium oxide coated. In addition, a fluorescent lamp in which the amount of titanium oxide used is greatly reduced as in the present invention is almost the same as a lamp without coating titanium oxide, and the problem of high starting voltage has also been solved.

It should be noted that the amount of adhesion of titanium oxide and the superimposed percent value of the phosphor shown in the above examples naturally vary depending on the particle size of the titanium oxide and each phosphor used, and furthermore, as mentioned above, Since the peak wavelength of the divalent europium-activated alkaline earth metal helophosphate phosphor can be changed appropriately, the color temperature of the resulting fluorescent lamp is not limited to the examples.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the fluorescent lamp of the present invention, Fig. 2 is a sectional view showing the coating structure of a general anti-fading fluorescent lamp, and Fig. 3 is a sectional view showing the coating structure of a general anti-fading fluorescent lamp.
The figure shows the reflection spectra of the ice external ray absorbing material and the phosphor. Figure 4 shows the ultraviolet absorption effect of the phosphor used in the present invention in a fluorescent lamp compared with that of a conventional phosphor. Figure 5 is a characteristic diagram showing the emission spectrum distribution of each phosphor No. 1 to 5 in Table 1, FIG. 6 is a characteristic diagram showing the light color of the lamp in Examples 1 to 3 of the present invention, and FIG.
The figure is a characteristic diagram showing the spectral energy of the lamps shown in Examples 1 to 3 of the present invention, and FIG. 8 shows N in Table 3. FIG. 9 is a characteristic diagram showing the light color of the lamp in Example 4.5 of the present invention, and FIG. 10 is a characteristic diagram showing the emission spectrum distribution of each phosphor in Examples 4.5 of the present invention. FIG. 3 is a characteristic diagram showing the spectral energy distribution of the lamp shown in FIG. 1.11...Glass tube, 2,12...First layer, 3゜13...Second layer or higher layer, 14.15...Discharge electrode.

Claims (6)

[Claims] (1) Form a first layer by coating the inner surface of the glass tube with a substance that transmits or reflects visible light and absorbs ultraviolet rays, and further coats the first layer with a phosphor that emits light in the visible wavelength range. In a fluorescent lamp formed by depositing a second or higher layer, the second or higher layer has the general formula M_5_-_xX(PO_4)_3:Eu^2^+
(x) [However, M in the formula consists of three types of Ba, Ca, and Mg, each having 3.0 to 4.5 gram atoms of Ba, 0.5 to
has a ca of 2.0 gram atom and Mg of 0.01 to 1.0 gram atom, x is a single substance or a mixture of two or more of F, Cl, and Br, and 0.01<x≦0 a first phosphor made of an alkaline earth metal halophosphate activated with divalent europium and having an emission peak in the wavelength range of 450 to 500 nm;
It has an emission peak in the wavelength range of 0 to 640 nm, and 1
A fluorescent lamp characterized by using a mixture of a second phosphor having a half width of 20 to 150 nm. (2) The fluorescent lamp according to claim 1, wherein the second phosphor is a tin-activated strontium magnesium orthophosphate phosphor. (3) The fluorescent lamp according to claim 1, whose color rendering index belongs to color rendering AAA according to JIS Z9112. (4) Form a first layer by coating the inner surface of the glass tube with a substance that transmits or reflects visible light and absorbs ultraviolet rays, and further coats the first layer with a phosphor that emits light in the visible wavelength range. In a fluorescent lamp formed by depositing a second or higher layer, the second or higher layer has the general formula M_5_-_xX(PO_4)_3:Eu^2^+
(x) [However, M in the formula consists of three types of Ba, Ca, and Mg, each having 3.0 to 4.5 gram atoms of Ba, 0.5 to
has a ca of 2.0 gram atom and Mg of 0.01 to 1.0 gram atom, x is a single substance or a mixture of two or more of F, Cl, and Br, and 0.01<x≦0 a first phosphor made of an alkaline earth metal halophosphate activated with divalent europium and having an emission peak in the wavelength range of 450 to 500 nm;
It has an emission peak in the wavelength range of 0 to 640 nm, and 1
A fluorescent lamp characterized in that it uses a mixture of a second phosphor having a half width of 20 to 150 nm and a third phosphor consisting of an antimony and manganese activated calcium fluoroapatite phosphor. (5) The fluorescent lamp according to claim 4, wherein the second phosphor is a tin-activated strontium magnesium orthophosphate phosphor. (6) The fluorescent lamp according to claim 4, whose color rendering index belongs to color rendering AA according to JIS Z9112.