JP3515737B2 - Phosphor and fluorescent lamp using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a phosphor activated with divalent europium and divalent manganese and a fluorescent lamp using the same.

[0002]

Since the practical use of a three-wavelength fluorescent lamp, it has been widely used as a fluorescent lamp with high efficiency and high color rendering in the field of indoor lighting, and its performance has been improved. The three-wavelength fluorescent lamp uses a phosphor film in which a mixture of three phosphors of blue, green, and red that emits light in a narrow band is adhered to the inner surface of the tube. Has a great influence on the brightness (luminous flux) and color rendering of the lamp, and is known to be a particularly important phosphor among the above phosphors.

As such a blue phosphor, a conventional blue phosphor is disclosed, for example, in Japanese Patent Publication No. 52-22836.
An aluminate phosphor activated with a valent europium or a halophosphate phosphor activated with a divalent europium described in JP-B-46-40604 has been used.

[0004]

However, although the above-mentioned conventional blue phosphor provides satisfactory characteristics with respect to the luminous flux when used in a three-wavelength fluorescent lamp, it is more demanded by the market society in recent years. There is a problem that the luminous flux is reduced when an attempt is made to provide good color rendering.

That is, in order to obtain a good color rendering property with an average color rendering index exceeding 84, the spectral distribution of the emission of the blue phosphor is improved and the emission color is represented by CIE chromaticity coordinates (x, y). The value should increase. In order to adjust the spectral distribution of the light emission of such a blue phosphor, a method of changing the crystal field of divalent europium, which is a light emitting ion of these phosphors, has been generally used.
In the case of an aluminate phosphor activated with divalent europium, a part of the barium element substituted with divalent europium is replaced with strontium, calcium or the like. However, with such a conventional method, the spectral distribution of the light emission of the blue phosphor can be adjusted to a desired one, but at the same time, there is a problem that the emission intensity thereof is reduced.

Further, Japanese Patent Publication No. 7-2947 discloses a method in which silicon oxide is solid-dissolved in an aluminate phosphor activated with divalent europium in which a part of barium element is replaced with strontium, calcium and the like. , It is described that the emission intensity is increased. However, Japanese Patent Publication No. 7-2947 does not contain divalent manganese as an activator, so that the solid solution effect of silicon oxide is 2
It was unclear how the aluminate phosphor activated with valent europium and divalent manganese would be expressed. This is because the emission of divalent manganese in this phosphor is the emission called sensitized emission caused by the energy transition from divalent europium in the same phosphor crystal, and the solid solution of silicon oxide is this energy. This is because it is not possible to predict how it will affect the transition probability.

Further, Japanese Patent Publication No. 52-22836 discloses an aluminate phosphor activated with divalent europium and divalent manganese, which emits blue light based on divalent europium and 2 Phosphors that simultaneously emit green emission based on valent manganese are shown. This phosphor can be used as a blue component of a three-wavelength fluorescent lamp having a good color rendering property with an average color rendering index of more than 84. However, in this case, although satisfactory color rendering can be obtained, there is a problem in that the luminous flux is significantly reduced.
This is because, in the case of this phosphor, an increase in green emission due to divalent manganese is accompanied by a decrease in blue emission due to divalent europium.

The present invention solves such problems, and an object of the present invention is to provide a phosphor showing good color rendering properties without a reduction in luminous flux and a fluorescent lamp using the same.

[0009]

In order to solve this problem, the present inventor has studied conventional aluminate phosphors activated with divalent europium and divalent manganese,
Alkaline earth metal aluminate compound with at least 1 selected from yttrium oxide and gadolinium oxide
A blue phosphor having a high emission intensity is realized by solid-dissolving a rare earth oxide and silicon oxide.

That is, the phosphor of the present invention is an aluminate phosphor activated with divalent europium and divalent manganese, and its chemical composition is represented by the following general formula.

[0011] _{(Ba 1-xy Eu x M} y) O · a (Mg 1-p Mn p) O · bAl 2 O 3 · cLn 2 O 3 · zSiO 2 , provided that at least 1 M is selected from Sr and Ca Ln represents at least one element selected from Y and Gd, where x, y, z, a, b, c and p are 0.05 ≦ x ≦ 0.2, 0 ≦. y ≦ 0.5, 0 <z
≦ 2.0, 0.5 ≦ a ≦ 4.0, 4 ≦ b ≦ 10, 0 <c
It is represented by ≦ 1.0 and 0 <p ≦ 0.2.

Further, the fluorescent lamp of the present invention is characterized in that the fluorescent substance of the present invention is adhered to the inner surface of the tube.

As a result, higher light emission is obtained as compared with the conventional one using the aluminate phosphor activated with divalent europium and divalent manganese in which yttrium oxide, gadolinium oxide and silicon oxide are not dissolved. Intense phosphors and fluorescent lamps are obtained.

Further, the fluorescent lamp of the present invention comprises the phosphor of the present invention (first phosphor), trivalent cerium and trivalent cerium having a spectral distribution having a maximum emission wavelength in the wavelength range of 530 to 550 nm. Terbium activated rare earth silicate phosphor, rare earth magnesium aluminate phosphor,
A second phosphor of at least one selected from a rare earth phosphate phosphor, a rare earth silicophosphate phosphor and a magnesium borate phosphor, and 600 to 620 nm
And a third phosphor composed of a trivalent europium-activated rare earth oxide phosphor showing a spectral distribution having a maximum emission wavelength in the wavelength range Characterize.

As a result, the luminous flux is not reduced and
A fluorescent lamp having good color rendering can be obtained.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an aluminate phosphor activated with divalent europium and divalent manganese and a fluorescent lamp using the same according to the present invention will be described in detail below.

(Embodiment 1) When a phosphor is used as a blue light emitting component of a three-wavelength fluorescent lamp, in order to increase the color rendering of the fluorescent lamp to 84 or more in average color rendering index,
As a method of adjusting the emission spectral distribution of the aluminate phosphor activated with divalent europium and divalent manganese, a plurality of alkaline earth metals can be used as shown in the general formula of the phosphor of the present invention. Is introduced to widen the spectral distribution of light emission by divalent europium to the longer wavelength side, and the method by which the addition amount of divalent manganese ion is increased to increase the emission of divalent manganese. However, these two methods are
All reduce the main emission of this phosphor, when used as a blue emission component of a three-wavelength fluorescent lamp,
Although the color rendering property was improved, the reduction of the luminous flux was unavoidable.

Therefore, an alkaline earth metal aluminate phosphor activated by divalent europium and divalent manganese having a spectral distribution of light emission suitable for a three-wavelength fluorescent lamp having an average color rendering index of 84 or more is obtained. Focusing attention, we examined how to increase the emission intensity.

As a result, the conventional divalent europium and 2
Luminescence intensity of at least one rare earth oxide selected from yttrium oxide and gadolinium oxide and silicon oxide in solid solution in alkaline earth metal aluminate phosphor activated with divalent manganese. I found that I can raise. Then, by using this blue phosphor, it is possible to obtain a three-wavelength type fluorescent lamp that realizes high color rendering properties without a reduction in luminous flux.

In the phosphor of the present invention, the chemical composition of the phosphor is represented by the following general formula (Ba _1-xy Eu _x M _y ) O.a (Mg _1-p Mn _p ) O.bAl ₂ O ₃ .cLn ₂ When represented by O ₃ · zSiO ₂ , M represents at least one element selected from Sr and Ca, Ln represents at least one element selected from Y and Gd, and x, y, z, a , B,
The amounts of c and p are limited as shown below.

That is, x represents the concentration of europium as the activator, and is limited within the range of 0.05≤x≤0.2. If x is less than 0.05, sufficient emission intensity cannot be obtained, and if x exceeds 0.2, the emission intensity decreases due to concentration quenching. y represents the addition amount of at least one element selected from Sr or Ca, and 0 ≦ y ≦
In the range of 0.5, characteristics equal to or higher than the characteristics at y = 0 can be obtained. z represents the amount of silicon oxide added, and 0 <
It is limited by z ≦ 2.0. Further, c indicates the amount of Ln added, and is limited to 0 <c ≦ 1.0. The emission intensity increases as z and c increase, but as shown in FIG. 1, when c exceeds 0 = c ≦ 1.0 and z exceeds 1.0, the emission intensity is lower than that at z = 0. turn into. In addition,
In FIG. 1, c is 0.1.

A is M partially substituted by Mn
It shows the composition of gO and is limited to 0.5 ≦ a ≦ 4.0. As described above, when utilizing the emission of divalent manganese in which a part of Mg is replaced, it is also known that a part of Mg is replaced by Zn. In the phosphor of the present invention, the substitution of Zn did not significantly improve the emission intensity, but a small amount may be added. Further, b represents the composition of Al ₂ O ₃ and is limited to 4 ≦ b ≦ 10.

Since these a and b influence each other, it is better to make b smaller if a is made smaller, and it is possible to obtain higher light emission intensity if b is made larger if a is made larger. The range satisfying both is limited as described above. p represents the concentration of manganese, which is the other activator, and is limited to 0 <p ≦ 0.2.

The emission of divalent manganese is 510 to 520n.
It shows the main light emission in m, and when added to the blue light emission component of a three-wavelength fluorescent lamp, it is known that it is effective in improving the color rendering properties, but if added in excess, it will significantly reduce the luminous flux of the lamp. Became clear. Therefore, p is limited to 0.2 or less.

(Second Embodiment) In the second embodiment, an example of the fluorescent lamp of the present invention will be described.

A partially cutaway sectional view of the fluorescent lamp of the second embodiment is shown in FIG. The fluorescent lamp of Embodiment 2 includes a glass bulb 11, electrodes 12 formed on both ends of the glass bulb 11, and a fluorescent film 13 formed on the inner surface of the glass bulb.
And mercury and an inert gas (not shown) enclosed in the glass bulb 11. It should be noted that FIG. 3 shows only one end of the fluorescent lamp, but the other end is also the same, so the illustration thereof is omitted. The fluorescent film 13 is the same as in the first embodiment.
It contains at least the phosphor described in 1.

(Embodiment 3) In Embodiment 3, another example of the fluorescent lamp of the present invention will be described.

The structure of the fluorescent lamp of the third embodiment is the same as that of FIG. 3 described in the second embodiment. The phosphor film 13 is composed of the phosphor (first phosphor) described in the first embodiment, and trivalent cerium and trivalent terbium having a spectral distribution having a maximum emission wavelength in the wavelength range of 530 to 550 nm. An activated rare earth silicate phosphor, a rare earth magnesium aluminate phosphor, a rare earth phosphate phosphor, a rare earth silicophosphate phosphor and at least one selected from magnesium borate phosphors; At least a mixture containing the second phosphor and a third phosphor composed of a trivalent europium-activated rare earth oxide phosphor showing a spectral distribution having a maximum emission wavelength in the wavelength range of 600 to 620 nm. I'm out.

The second phosphor is LaPO ₄ : (C
e, Tb), CeMgAl ₁₁ O ₁₉ : (Tb) and GdM
gB ₅ O ₁₀ : (Ce, Tb) and the like.

The third phosphor is Y ₂ O ₃ : E.
u is mentioned.

[0031]

EXAMPLES Examples of the present invention will be described below.

Example 1 As raw materials for the phosphor, BaCO ₃ : 0.80 mol SrCO ₃ : 0.10 mol MgO: 1.05 mol Al ₂ O ₃ : 6.0 mol Y ₂ O ₃ : 0.10 mol SiO _{2 : 0.50mol Eu 2 O 3: 0.05mol} MnCO 3: weigh 0.06 mol, thoroughly mixed. This raw material mixture was placed in an alumina crucible and fired at 1400 ° C. for 3 hours in a reducing atmosphere using a mixed gas of 95% by volume nitrogen and 5% by volume hydrogen. The obtained fired product was crushed, washed with pure water, filtered and dried to obtain the phosphor of the present invention. The composition of this phosphor was (Ba _0.8 Sr _0.1 Eu _0.1 ) O ・ 1.1 (Mg _0.95 Mn _0.05 ) O ・ 6Al ₂ O ₃・ 0.1Y
_{It was 2} O ₃ .0.5SiO ₂ .

The emission intensity of this phosphor excited by ultraviolet light of 254 nm was calculated by burning without using silicon oxide (Ba _0.8
Sr _0.1 Eu _0.1 ) O · 1.1 (Mg _0.95 Mn _0.05 ) O · 6Al ₂ O ₃ was significantly improved by 113% as compared with the phosphor. In addition, this phosphor is used as a blue phosphor and as a green phosphor (La _0.5 Ce _0.2 Tb
_0.3 ) PO ₄ and (Y _0.98 Eu _0.02 ) ₂ O ₃ as a red phosphor are mixed in a mass ratio of 16%, 43% and 41%, respectively, and a straight tube belonging to the daylight white light color section is produced by the usual manufacturing method. A 40 W fluorescent lamp was produced.

(Comparative Example) As a blue phosphor, (Ba _0.9 Eu _0.1 ) O.MgO.6Al ₂ O ₃ which was conventionally used was used, except that
A straight tube 40 W fluorescent lamp was produced in the same manner as in Example 1.

Comparing the fluorescent lamp of Example 1 with that of the comparative example, the luminous flux of the fluorescent lamp of the present invention of Example 1 after 100 hours of lighting is improved by 7% as compared with the luminous flux of the fluorescent lamp of the comparative example. It was

On the other hand, the average color rendering index Ra of the fluorescent lamp of the present invention was 89, and it was confirmed that the fluorescent lamp had a satisfactory high color rendering property.

FIG. 2 is a diagram showing the spectral distribution of the fluorescent lamp in the first embodiment.

(Examples 2 to 14) In the same manner as in Example 1, phosphors A to Q shown in Table 1 were combined as shown in Table 2 to produce a straight tube 40W fluorescent lamp. One for each lamp
Table 2 shows the values of the luminous flux L and the average color rendering index Ra after lighting for 00 hours. The luminous flux L in Table 2 was obtained according to the following formula.

L = m / n × 100 where m = luminous flux of the fluorescent lamp of the embodiment after 100 hours of lighting (lm) n = luminous flux of fluorescent lamp of the comparative example after 100 hours of lighting (l)
m)

[0040]

[Table 1]

[0041]

[Table 2]

As is clear from Table 2, the fluorescent lamps of Examples 1 to 14 of the present invention have been widely used as the blue phosphor of the three-wavelength fluorescent lamp (Ba _0.9 Eu _0.1 ) O.MgO.
It can be seen that, as compared with the fluorescent lamp shown in the comparative example using the 6Al ₂ O ₃ phosphor, the luminous flux has a higher luminous flux while maintaining and improving good color rendering properties.

Although the straight tube fluorescent lamp is used in the present embodiment, the present invention can obtain the effect even when applied to the ring fluorescent lamp or the compact fluorescent lamp directly or together with the protective film. .

[0044]

As described above, according to the present invention, it is possible to provide a fluorescent lamp having a luminous flux higher than that of a conventional three-wavelength fluorescent lamp in addition to good color rendering properties. The target value is great.

[Brief description of drawings]

FIG. 1 is a diagram showing a relative peak height of luminescence intensity when a solid solution amount of SiO ₂ is changed in the phosphor of the present invention.

FIG. 2 is a diagram showing a spectral distribution of a fluorescent lamp in Example 1.

FIG. 3 is a partially cutaway sectional view showing an example of a fluorescent lamp of the present invention.

[Explanation of symbols] 11 glass bulbs 12 electrodes 13 Fluorescent film

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI C09K 11/79 CPR C09K 11/79 CPR 11/81 CPM 11/81 CPM CPW CPW CQD CQD CQF CQF H01J 61/44 H01J 61/44 NP (58) Fields surveyed (Int.Cl. ⁷ , DB name) C09K 11/08-11/89 H01J 61/44

Claims (3)

(57) [Claims] 1. An aluminate phosphor activated with divalent europium and divalent manganese, the chemical composition of which is represented by the following general formula. _{(Ba 1-xy Eu x M} y) O · a (Mg 1-p Mn p) O · bAl 2 O 3 · cLn 2 O 3 · zSiO 2 , provided that at least one element M is selected from Sr and Ca Ln represents at least one element selected from Y and Gd, and x, y, z, a, b, c and p in the formula are 0.05 ≦ x ≦ 0.2 and 0 ≦ y ≦ 0. .5, 0 <z
≦ 2.0, 0.5 ≦ a ≦ 4.0, 4 ≦ b ≦ 10, 0 <c
It is represented by ≦ 1.0 and 0 <p ≦ 0.2. 2. A fluorescent lamp formed by applying the phosphor according to claim 1 on the inner surface of a tube. 3. The phosphor according to claim 1, and 530 to 5
A trivalent cerium and trivalent terbium activated rare earth silicate phosphor, a rare earth magnesium aluminate phosphor, a rare earth phosphate phosphor showing a spectral distribution having a maximum emission wavelength in a wavelength range of 50 nm, A second phosphor comprising at least one selected from a rare earth silicophosphate phosphor and a magnesium borate phosphor;
A mixture containing a third phosphor, which is a trivalent europium-activated rare earth oxide phosphor showing a spectral distribution having a maximum emission wavelength in the wavelength range of ˜620 nm, was formed by coating on the inner surface of the tube. Fluorescent lamp.