JPH01129091A - phosphor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention provides an improvement in green-emitting rare earth aluminate/silicic acid/phosphate or rare earth orthophosphate phosphors activated with cerium and terbium. Regarding.

(Prior Art) In recent years, three-wavelength fluorescent lamps that simultaneously satisfy high color rendering properties and high efficiency have become widely used as general lighting fluorescent lamps.

This type of fluorescent lamp uses blue, green, and red emitting phosphors that have a relatively narrow emission spectral distribution.

Conventional green-emitting rare earth aluminate/silicate/phosphate phosphors activated with cerium and terbium include [(RE,
Ce, Tb), 03・^12203'5iOz"PJi
l (Special Publication Showa 6O-9543) or [(RE, Ce
, Tb, A), 0.・SiO, ・P, O, ](]
Special Publication No. 59-10065 or as a rare earth orthophosphate [(RE-Ce-Tb)POJ (Special Publication No. 59-43
508) is known. In addition, in a three-wavelength fluorescent lamp, the proportion of the green-emitting phosphor in the total luminous flux (emission output) is very high, so the characteristics of the green-emitting phosphor are the same as those of the three-wavelength fluorescent lamp. has a major impact on

(Problems to be Solved by the Invention) Therefore, in a three-wavelength fluorescent lamp, it is necessary to use a green-emitting phosphor with excellent performance and stability. However, conventional rare earth aluminate/silicate/phosphate phosphors or rare earth orthophosphate phosphors tend to have larger chromaticity (x, y) fluctuations during lighting in a fluorescent lamp than red-emitting phosphors. Was.

As a result of intensive investigation, experimentation, and analysis of the factors, it was discovered that the halogen element group (F, CQ, Or, I) has a large effect on the green phosphor.

That is, the halogen element group (F, C
The content of Brt I) significantly affects the chromaticity (xyy) fluctuation during lighting of a fluorescent lamp.

As mentioned above, it is desirable to have a green-emitting phosphor for three-wavelength fluorescent lamps that has high luminous output and has small chromaticity (x, y) fluctuations during lighting in the fluorescent lamp. .

Therefore, the present invention was made to solve the above problems, and it is a green-emitting rare earth aluminic acid that exhibits high luminescence under 254 nm mercury emission line excitation and has small chromaticity (x ty) fluctuations during lighting in a fluorescent lamp. - The purpose is to provide a silicic acid/phosphate phosphor or a rare earth orthophosphate phosphor.

[Structure of the invention]

(Means for Solving the Problems) The phosphor of the present invention is activated by cerium and terbium, and contains 0.01 ppm≦h≦50 ppm of halogen elements (
However, h contains at least one of fluorine F, chlorine CQ, bromine Br, and iodine), Re is at least one of yttrium, lanthanum, and gadolinium, and a
> O, b) O* O< a + b + 1,
x≧Op'/≧O, z≧0, 0.85≦x+y+z
When ≦1.15, the general formula (Ret-a-bceaT
bb) go3e x AQ, O,・y Sin,・zP
, Os.

(Function) Halogen element group (F, cQ, Be, I
) when the concentration is from 0.01 ppm to 5 oppI, good luminous output and small fluctuations in chromaticity (xyy) during lighting in a fluorescent lamp can be obtained, but when the concentration is below 0.01 ppm, the luminous output decreases significantly. . In addition, the luminous output decreases at 50 ppw+ or more, and the chromaticity (
x, y) fluctuations increase.

From this, it is found that the luminescent halogen element group (F,
CQ, Be, I) from 0.01ppit to 50pp
By introducing quantity control in the range up to m, it is possible to produce a phosphor that has high emission brightness under 254n mercury emission line excitation and has small fluctuations in chromaticity (x, y) during lighting in a fluorescent lamp. The contribution of practical application is significant.

(Example) The phosphor of the present invention can be synthesized as follows, and the results are shown in Table 1.

Example-1 Lanthanum oxide (La, O,) 266.31 g, cerium oxide (Cent) 168.82 g - Terbium oxide (Tb40.) 122.22 gt Silicon dioxide (SiO)
l) 4.91 g, aluminum oxide (Affi, 0
3) 1.67 g diammonium hydrogen phosphate [(N
H, ), HPO, ] 4436.07 g and 120 μg of potassium fluoride (KF) were thoroughly ground and mixed using a ball mill. Place this raw material mixture in a crucible and add 3 carbon powders.
After adding 0g, put a lid on the crucible and expose it to the atmosphere.
Bake at ℃ for 2 hours.

The obtained baked product is pulverized into fine powder and thoroughly washed with warm pure water at 70 to 90°C. After that, the fired product is filtered and dried.

Further, the dried fired product is packed in a crucible and fired at 1200° C. for 4 hours in a reducing atmosphere consisting of a mixed gas of 95% by volume of nitrogen and 5% by volume of hydrogen.

The phosphor obtained in this way is shown in Table 1.
As shown in 4, F e Cj! e Br F
The total abundance of I is denoted by 2PP- (Lao, 6o C
eo, ao Tbo, zo)zO,'0.01Affi
,O,"0.05SiO," 1.0IP20. It is a rare earth aluminate, silicic acid, and phosphate phosphor.

This phosphor has a peak emission wavelength of 5 when excited by ultraviolet light.
It emits strong green light around 45 nm. This phosphor was added to a 37 Watt fluorescent lamp FL-408 using the usual method.
5-G137 was manufactured and the load was increased by 10% of the rating.

Initial luminescence output was measured under these conditions. Furthermore, the initial luminescence chromaticity was measured using a commercially available colorimeter.

Next, this fluorescent lamp was turned on, and the luminous chromaticity of the fluorescent lamp was measured after 100 hours.

The initial luminous output of a fluorescent lamp using this phosphor is 100
(relative value), and the variation in luminescent chromaticity is +
0.001. The y value was +0.001.

Example-2 Lanthanum oxide (La20.) 146.45 g, cerium oxide (CaO,) 92.84 g, terbium oxide (Tb, 0.) 67.21 g.

Silicon dioxide (SiO,) 2.70 g, aluminum oxide (All□0.) 0.92 g, diammonium hydrogen phosphate [(NH,), HPO,] 239.81 g
', 150 µm of sodium chloride (NaCl2), and 115 µm of ammonium iodide (NH4I) were thoroughly ground and mixed using a ball mill. This raw material mixture is fired and treated under the same conditions as in Example-1.

The obtained phosphor has a total content of halogen elements of 10 pP, as shown in &-5 of Table 1 (Lao
, 50 c6G, ao TbO, 20), , O, ·0.
001AQ,O,・0.05Sin,・i,oxp,o
It is a rare earth aluminic acid/silicic acid/phosphate phosphor represented by s. This phosphor emits strong green light with an emission peak wavelength around 545 nm when excited by ultraviolet light. In addition, a fluorescent lamp was produced using this phosphor under the same conditions as in Example 1, and the initial light emission output and fluctuations in the luminous chromaticity were measured. (Difference between 100 hours later and the initial stage) The initial luminous output of the fluorescent lamp using the phosphor of this example is 100 (relative value), and the variation in luminous chromaticity is
+0.001 in value. The y value was +0.001.

Hereinafter, for samples &-2, 3, 6, 7, and 8, F,
Experiments were conducted by varying the total gold content of C1, Br, and I, and the results are shown in Table 1.

Next, as a comparative example, the samples in Table 1 &-1°Ha-9
and &-10. The preparation method is as described in Example-1 and Example-2, and F, CQ, and Br.

and the total gold abundance of I is 0.001.100 and 500
It is obtained by mixing predetermined amounts of fluoride, chloride, bromide, and iodide, such as in ppm, and is not particularly influenced by the type of compound.

(Left below) Table 1. Relationship between halogen element concentration in phosphor and lamp characteristics. The light output is the average relative light output of n=100 lamps.

The variation in brightness is the X value - 0 after 100 hours for n = 100 pieces.
The X value of time and the y value after 100 hours - the y value after 0 hours.

The content of the halogen element group (F+ cQt I I Br) is 0. In the case of OOlppm, the initial luminescence output is 96 (relative value), which shows a slight tendency to decrease compared to the phosphor of the present invention. In addition, at 1100 ppm and 500 ppm, the initial luminous output greatly decreased to 94 and 80, and furthermore, the fluctuation of the luminous chromaticity also increased to +0.006 and +o in the X value.
oos and y values of +o, oos, and +0.010, resulting in a significant deterioration of characteristics.

In addition, in the examples of the present invention, in both Example-1 and Example-2, the phosphor matrix is a rare earth aluminic acid, silicic acid,
Although we have mentioned phosphates, rare earth orthophosphates also contain halogen element groups (F, CQ.

The effects of Br and I) are exactly the same, and the phenomena and effects do not change due to differences in the parent. Furthermore, the effect does not change at all depending on the type and combination of halogen element groups (F, CQ, Br, I).

Moreover, the effect does not change at all depending on the type of halogen compound.

〔Effect of the invention〕

As explained above, the phosphor of the present invention makes it possible to realize a rare-earth green light-emitting phosphor that has high light emission output and has small fluctuations in chromaticity (x, y) during lighting in a fluorescent lamp.

Agent: Patent Attorney Noriyuki Chika Same Kikuo Takehana

Claims (3)

[Claims] (1) Contains 0.01ppm≦h≦50ppm of a halogen element (where h is at least one of fluorine F, chlorine Cl, bromine Br, and iodine I), and has the general formula (Re_1_-_a_-_bCe_aTb_b)_2O
_3・xAl_2O_3・ySiO_2・zP_2O_
A phosphor characterized by being represented by 5. (However, Re
is at least one of yttrium Y, lanthanum La, and gadolinium Gd, and a>0, b>0, 0<a+b
+1, x≧0, y≧0, z≧0, 0.85≦x+y+z
≦1.15) (2) The phosphor according to claim 1, characterized in that x+y>0, y+z>0, and z+x>0. (3) The phosphor according to claim 1, wherein x=0 and y=0.