JPH08283712A - Three-wavelength-region-emission fluorescent lamp - Google Patents

Abstract

PURPOSE: To obtain a fluorescent lamp having high color rendering properties and a high efficiency and reduced in aging with time. CONSTITUTION: The three-wavelength-region-emission fluorescent lamp having a fluorescent film made of a luminescent composition comprising a bivalent europium and manganese-coactivated alkaline earth metal aluminate phosphor represented by the formula: Ba1-x-y Srx Euy Mg1-z Mnz Al10 O17 (wherein x, y and z are in the ranges: 0.1<=x<=0.4, 0.075<=y<=0.4, and 0.005<=z<=0.05).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-wavelength band emission type fluorescent lamp provided with an alkaline earth aluminate phosphor co-activated with divalent europium and divalent manganese as a fluorescent film.

[0002]

2. Description of the Related Art In recent years, in the field of general lighting lamps, three-wavelength band emission type fluorescent lamps (hereinafter, the three-wavelength band emission type fluorescent lamps are simply referred to as "fluorescent lamps") have been developed. It has been developed and put into practical use. The phosphor used in this fluorescent lamp is a mixture of three kinds of phosphors of red, green and blue which have a relatively narrow band emission spectrum distribution in an appropriate ratio. The phosphors used in this fluorescent lamp are trivalent europium-activated yttrium oxide as a red phosphor, cerium and terbium-activated lanthanum phosphate as a green phosphor, alkaline earth chlorophosphate as a blue phosphor, or Divalent europium-activated barium magnesium aluminate is used in each case.

This fluorescent lamp is excellent in terms of both luminous flux and color rendering. The average color rendering index (Ra) is 84, and the luminous flux is, for example, a straight tube fluorescent lamp, FL20SSEX.
-N / 18 has achieved 1470 lumens (1 m). Furthermore, by adding blue-green or blue-green and deep-red phosphors to the above-mentioned three kinds of phosphors and mixing four or five kinds of phosphors, a fluorescent lamp realizing Ra = 87 or more is put to practical use. It became so. Furthermore, JP-A-5-302
As disclosed in JP-A-082, by specifying the composition and emission color of a divalent europium-activated alkaline earth chlorophosphate phosphor, which is a blue component, by mixing only three kinds of phosphors, A fluorescent lamp with Ra = 87 or more has been realized.

On the other hand, divalent europium as a blue component
Uses activated barium magnesium aluminate phosphor
As for the fluorescent lamp,
Barium magnesium aluminate phosphor with divalent man
The one with improved color rendering by co-activating cancer
It has been put to practical use. Also, JP-A-56-86892
In the report, Ba_1-xySr_xMg_pAl_qO _{1 + p + q / 2q}: E
u²⁺(Where 0 <x ≦ 0.1, 0.01 ≦ y ≦ 0.4,
Fluorescence represented by 0.8 ≦ p ≦ 4.0.10 ≦ q ≦ 30)
Ra = 89 can be realized by using the body
It has been disclosed.

A fluorescent lamp using a divalent europium-activated barium magnesium aluminate phosphor as a blue component is more luminous than a fluorescent lamp using a divalent europium-activated alkaline earth chlorophosphate phosphor. However, there is also a problem that the change over time (color shift) in the emission color of the fluorescent lamp due to the deterioration of the phosphor is large.

Therefore, as a method for solving this problem,
A europium-activated alkaline earth aluminate phosphor having a very limited composition or a europium-manganese co-activated alkaline earth aluminate phosphor is a europium-activated yttrium oxide (hereinafter referred to as “YOX red phosphor”) and It is disclosed in Japanese Patent Application Laid-Open No. 4-106 that a mixture of terbium and cerium co-activated lanthanum phosphate (hereinafter referred to as “LAP green phosphor”) is mixed in a limited mixing ratio.
No. 187 and Japanese Patent Laid-Open No. 4-106188. However, it is desired to realize a fluorescent lamp with higher color rendering, higher efficiency and less color shift.

[0007]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a three-wavelength light emitting type fluorescent lamp with high color rendering, high efficiency and little deterioration.

[0008]

In order to solve the above-mentioned problems, as a result of various studies on the composition of the phosphors used and combinations thereof, one of barium of the divalent europium-activated barium magnesium aluminate phosphor was obtained.
Part is replaced with strontium by a predetermined amount, and one part of magnesium is replaced with manganese by a predetermined amount, and further a phosphor is formed (Ba + Sr + Eu) :( M
g + Mn): Al element ratio of divalent europium and manganese co-activated barium strontium magnesium aluminate phosphor with a ratio of 1: 1: 10 and a predetermined ratio limited to YOX red phosphor and LAP green phosphor. It was found that it is possible to provide a fluorescent lamp having high color rendering, high efficiency and little deterioration by using the luminescent composition obtained by mixing the above as a fluorescent film, and completed the present invention.

That is, the three-wavelength band emission type fluorescent lamp of the present invention has the general formula Ba _1-xy Sr _x Eu _y Mg _1-z Mn _z A
l ₁₀ O ₁₇ (where x, y and z are each 0.1 ≦ x ≦
0.4, 0.075 ≤ y ≤ 0.4 and 0.005 ≤ z ≤
It is a number that satisfies the condition of 0.05. The same applies hereinafter), which is characterized by having a phosphor film made of a light emitting composition containing a divalent europium and manganese co-activated alkaline earth aluminate phosphor.

[0010]

The fluorescent lamp of the present invention will be described in detail below. The divalent europium and manganese co-activated alkaline earth aluminate phosphors used in the fluorescent lamp of the present invention are Ba, Sr, Mg, Al, Eu and Mn oxides or easily oxidized at high temperatures. The compound of these elements which can be changed into a substance is stoichiometrically composed of the composition formula Ba _1-xy Sr _x E
u _y Mg _1-z Mn _z Al ₁₀ O ₁₇ are mixed in a ratio that satisfies the conditions, and 2 to 4 at 1200 to 1700 ° C. in a reducing atmosphere.
It is obtained by firing once or more over 0 hours.

The thus obtained divalent europium and manganese co-activated barium strontium magnesium aluminate phosphor has improved deterioration characteristics over time, but deterioration of this phosphor over time is suppressed. The reason is
By partially substituting barium in the barium magnesium aluminate phosphor matrix with strontium, the lattice constant c of the phosphor host crystal becomes shorter, resulting in Ba-
It is considered that the position of oxygen in the O layer was stabilized.

FIG. 1 and FIG. 2 respectively show the fluorescent lamp of the present invention.
Divalent europium used as a blue-emitting phosphor
Barium Strontium Magne Activated with Cobalt and Manganese
Cium aluminate phosphor (Ba_0.7Sr_0.2Eu_0.1
Mg_0.98Mn_0.02Al_TenO₁₇), And conventional fluorescent lamps
Divalent europium used as a blue-emitting phosphor
And manganese co-activated barium magnesium aluminate
Phosphor (Ba_0.9Eu _0.1Mg_0.98Mn_0.02Al
_TenO₁₇) About CuKα₁Incident characteristic X-ray
The powder X-ray diffraction pattern obtained when
And a bivalent europium and manganese co-activated burr
Umstrontium magnesium aluminate phosphor
In the case of (Fig. 1), the Miller index is located at the position of Miller index 008.
It has no maximum value independently of the diffraction peak of 110. one
, Bivalent europium and manganese co-activated barium
In case of gnesium aluminate phosphor, as shown in Fig. 2.
Powder X-ray diffraction pattern, with a Miller index of 008
In addition, the maximum value is set independently of the diffraction peak of Miller index 110.
To have. Here, it is said that X-rays do not independently have a maximum value.
If the folding strength is 1 and the diffraction angle 2θ is t degrees,
The fractional value dl / dt is the diffraction peak of Miller index 008 and the mirror
-Has a negative value between the diffraction peaks of index 110
Means no.

Curves a and b in FIG. 3 are used as the blue-emitting phosphor of the fluorescent lamp of the present invention, respectively.
Valent europium and manganese co-activated barium strontium magnesium aluminate phosphors and divalent europium and manganese co-activated barium magnesium aluminate phosphors used as blue-emitting phosphors of conventional fluorescent lamps. FIG. 3 is a graph showing an emission spectrum when excited with 7 nm ultraviolet light, and is shown by a curve a in FIG.
As can be seen from the comparison between the conventional barium magnesium aluminate phosphor and the conventional barium magnesium aluminate phosphor by replacing part of barium with strontium (curve a in FIG. 3), the conventional barium magnesium aluminate phosphor (FIG. The peak position of the emission due to europium shifts to the long wavelength side as compared with the curve b) of 1.

Further, manganese was partially substituted at the position of magnesium for co-activation, and this was mixed with a YOX red phosphor and a LAP green phosphor in a predetermined amount ratio and used as a light emitting composition of a fluorescent lamp. In this case, it is possible to provide a fluorescent lamp with high color rendering, high efficiency, and little deterioration. The barium strontium magnesium aluminate phosphor (Ba) which is a covalently activated divalent europium and manganese component which is a blue light emitting component of the light emitting composition for a fluorescent lamp of the present invention.
_{1-xy Sr x Eu y Mg} 1-z Mn z in Al ₁₀ O _17), a condition that y is 0.2 ≦ y ≦ 0.4 If x is in the range of 0.1 ≦ x ≦ 0.15 And x is 0.15 <
When in the range of x ≦ 0.4, 0.075 ≦ y ≦ 0.4
When a composition having a composition satisfying the following condition is used, a decrease in emission intensity of the fluorescent lamp over time is small, and a fluorescent lamp with little deterioration over time can be obtained.

The effect of suppressing deterioration with time similar to the case of substituting strontium for barium can be obtained by increasing the addition amount of europium as an activator, but it is a good idea to increase the amount of expensive europium. Not
There is also a problem that when the amount of europium added is increased, deterioration due to baking during manufacture of the fluorescent lamp becomes large. Therefore, when the characteristics of the fluorescent lamp of the present invention are compared with those of the conventional fluorescent lamp, the lamps using the blue phosphor having the same europium concentration should be compared with each other.

[0016]

【Example】

 (Example 1)

[0017]

Table 1 BaCO ₃ 0.7 mol SrCO ₃ 0.2 mol Eu ₂ O ₃ 0.05 mol ₃ MgCO ₃ · Mg (OH) ₂ 0.245 mol MnO ₂ 0.02 mol Al ₂ O ₃ (gamma type) 5.0 mol AlF ₃ 0.010 mol

The above raw materials are mixed and filled in a crucible, and a lump of graphite is placed on the raw material. A lid is placed on the raw material, and the maximum temperature is 1450 ° C. in a nitrogen-hydrogen atmosphere containing water vapor. It took time to bake.

Then, the calcined powder is dispersed, washed, dried and sieved.
Process (Ba_0.7Sr_0.2Eu _0.1OMg_0.98Mn
_0.02Al_TenO₁₇Activated divalent europium and manganese
Blue light emitting barium strontium magnesium aluminum
An acid salt phosphor was obtained. AlF₃In the manufacture of phosphors
It is a flux that is often used. Luminescence of this phosphor
The spectrum is shown in Figure 3a. 253.7n of this phosphor
The emission color when excited by ultraviolet rays of m is x = 0.141,
It was y = 0.159.

Phosphor 28.0 obtained as described above
% By weight, 35.2% by weight of YOX red phosphor, and 3
6.8 wt% LAP green phosphor was thoroughly mixed with butyl acetate together with a nitrocellulose lacquer to prepare a phosphor slurry, which was applied to a glass tube and dried, and then a fluorescent material with a color temperature of 5000K was applied by a usual method. Lamp (FCL64T6)
Was manufactured.

Further, the above raw materials were mixed in the proportions shown in Table 1 to obtain a divalent europium- and manganese-activated blue light emitting barium strontium magnesium aluminate phosphor, and also shown in Table 1. Example 1 above, except that a light-emitting composition in which a ratio of each color phosphor was mixed was used.
The fluorescent lamps of Examples 2 to 4 were obtained in the same manner as in. With respect to the initial characteristics of the fluorescent lamp thus obtained, the luminous flux was 100 relative to the fluorescent lamp of Comparative Example 1 below, and the average color rendering index Ra was 87.8.

(Comparative Example 1) Separately from this, raw materials other than SrCO ₃ described in Example 1 were mixed at a ratio of the compositional formula described in Comparative Example 1 of Table 1, and divalent europium and manganese-activated blue color was mixed. A fluorescent lamp of Comparative Example 1 was obtained in the same manner as in Example 1 except that a light emitting composition was obtained in which the light emitting barium magnesium aluminate phosphor was obtained and the phosphors of respective colors in the proportions shown in Comparative Example 1 of Table 1 were mixed. Got The emission chromaticity points (x, y values), initial luminous flux (relative values) and average color rendering index (Ra) of the thus obtained fluorescent lamps of Examples 1 to 4 and Comparative Example 1 were measured. Is shown in Table 1 together with the composition formula of the blue light emitting phosphor and the mixing ratio of each phosphor.

[0023]

[Table 2]

As can be seen from the results shown in Table 1, the fluorescent lamps of the present invention (Examples 1 to 5) were compared with the fluorescent lamp of Comparative Example 1 using the blue phosphor having the same europium concentration. The luminous flux was the same and the average color rendering index was improved, and the color rendering was further improved. Further, it was confirmed that the fluorescent lamps of Examples 1 to 4 were also improved in deterioration over time, but in particular, the improvement of deterioration over time during lighting of the fluorescent lamp of the blue phosphor used in Examples 1, 2 and 4 was confirmed. Example 3
It was slightly larger than the one.

(Example 5 and Comparative Example 2) Using the blue phosphors shown in Table 2, FCL64T6 was prepared in the same manner as in Example 1.
A three-wavelength light emitting type fluorescent lamp having a color temperature of 5000 K was manufactured. With respect to the fluorescent lamps of Example 5 and Comparative Example 2 thus obtained, the emission chromaticity points (x, y values), the initial luminous flux (relative value) and the average color rendering index (Ra) were measured and the results are shown in blue. The composition formula of the light emitting phosphor and the mixing ratio of each phosphor are shown in Table 1.

[0026]

[Table 3]

As can be seen from the results shown in Table 2, the fluorescent lamp of the present invention of Example 5 has the same luminous flux as the fluorescent lamp of Comparative Example 2 using the blue phosphor having the same europium concentration. And the average color rendering index has improved,
The color rendering property was further improved. It was confirmed that the fluorescent lamp of Example 5 was improved in deterioration over time as compared with the fluorescent lamp of Comparative Example 2. Further, it was slightly superior to Example 3 in terms of deterioration with time.

(Example 6, Comparative Example 3) Using the blue phosphors shown in Table 3, FCL64T6 was prepared in the same manner as in Example 1.
A three-wavelength light emitting type fluorescent lamp having a color temperature of 5000 K was manufactured. With respect to the fluorescent lamps of Example 6 and Comparative Example 3 thus obtained, the emission chromaticity points (x, y values), the initial luminous flux (relative value) and the average color rendering index (Ra) were measured and the results are shown in blue. The composition formula of the light emitting phosphor and the mixing ratio of each phosphor are shown in Table 1.

[0029]

[Table 4]

As can be seen from the results shown in Table 3, the fluorescent lamp of the present invention of Example 6 has the same luminous flux as that of the fluorescent lamp of Comparative Example 3 using the blue phosphor having the same europium concentration. And the average color rendering index has improved,
The color rendering property was further improved. It was confirmed that the fluorescent lamp of Example 6 was improved in deterioration over time as compared with the fluorescent lamp of Comparative Example 3. Moreover, it was slightly superior to Example 3 in terms of deterioration with time.

[0031]

According to the present invention, it is possible to provide a fluorescent lamp having high color rendering, high efficiency and little deterioration over time.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a powder X-ray diffraction pattern of a divalent europium- and manganese-activated blue light emitting barium strontium magnesium aluminate phosphor used in the fluorescent lamp of the present invention.

FIG. 2 is a diagram illustrating a powder X-ray diffraction pattern of a divalent europium- and manganese-activated blue light emitting barium magnesium aluminate phosphor used in a conventional fluorescent lamp.

FIG. 3 is a bivalent europium- and manganese-activated blue light emitting barium strontium magnesium aluminate phosphor used in the fluorescent lamp of the present invention and a divalent europium- and manganese-activated blue light emitting barium magnesium used in a conventional fluorescent lamp. Aluminate phosphor 253.
It is a figure which illustrates the emission spectrum when excited by a 7 nm ultraviolet ray.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuji Kawa, 1060 Narita, Odawara, Kanagawa Kasei Optonix Co., Ltd.Odawara factory (72) Inventor Naoto Kijima, 1000, Kamoshida-cho, Aoba-ku, Yokohama, Japan Mitsubishi Chemical Corporation Inside Yokohama Research Institute

Claims (5)

[Claims] 1. The general formula Ba _1-xy Sr _x Eu _y Mg
_{1-z Mn z Al 10 O} 17 ( where, x, respectively 0.1 ≦ y-and z x ≦ 0.4,0.075 ≦ y ≦ 0.4 and 0.
A phosphor film having a luminescent composition containing a divalent europium and manganese co-activated alkaline earth aluminate phosphor represented by the formula (005 ≦ z ≦ 0.05). A characteristic three-wavelength emission type fluorescent lamp. 2. When x is in the range of 0.1 ≦ x ≦ 0.15, y is 0.2 ≦ y ≦ 0.4 and x is 0.15 <x ≦ 0.4. When it is in the range
Is a number satisfying the condition of 0.075 ≦ y ≦ 0.4. 3. The three-wavelength band emission type fluorescent lamp according to claim 1, wherein 3. CuKα ₁ is added to the divalent europium and manganese co-activated alkaline earth aluminate phosphor powder.
The powder X-ray diffraction pattern obtained when a characteristic X-ray is incident does not have a peak independent of the diffraction peak of the Miller index 110 at the position of the diffraction peak of the Miller index 008. Item 3. A three-wavelength band fluorescent lamp. 4. The three-wavelength band emission type fluorescent light according to claim 1, wherein the light-emitting composition contains a trivalent europium-activated yttrium oxide fluorescent material. lamp. 5. The three-wavelength band emission type fluorescent light according to claim 1, wherein the luminescent composition contains terbium and cerium co-activated lanthanum phosphate phosphor. lamp.