JPS5945384A - Preparation of yttrium oxide fluorescent substance activated with europium - Google Patents

Abstract

PURPOSE:To obtain yttrium oxide fluorescent substance activated with europium having improved luminance characteristics, by calcining a raw material mixture containing barium borate. CONSTITUTION:A raw material mixture obtained by adding 0.001-0.5wt% calculated as boron oxide (B2O3) of barium borate to oxide of mixed rare earth elements of yttrium and europium is calcined in air at 1,200-1,500 deg.C, to give the desired yttrium oxide fluorescent substance activated with europium. EFFECT:Emission efficiency is improved by 0.5-3% under electron radiation excitation and by 1-8% under ultraviolet excitation.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention is directed to improvements in the production method of europium and activated yttrium oxide phosphors.

(Technical Background of the Invention and Seven Problems) Y2O3: Eu% as a red-emitting rare earth acid f arsenic phosphor activated with europium (<, (Bottle 1
120. : ■yu q6y) Yi body + L
a! Os ” ” '12-)' I: I L book,
(Y,G(1%03:,EuIl:
) ) t f book.

(Y, L a ) t 03 : Jb u phosphor and the like are known.

Among these, europium-activated yttrium oxide phosphor Y,
0. : Hu is a red light-emitting component of cathode ray tubes for color televisions because it is a yttrium compound as a main component and has excellent phosphor properties such as electric flux, ultraviolet rays, and two luminous colors due to IN. It is also being used as a phosphor for red light emitting components in deluxe type fluorescent lamps with improved color rendering properties for illumination.

Europium-activated yttrium oxide phosphor is produced by yttrium oxide (Y2O3)' or charcoal salt, nitric acid tH,x
Yttrium compounds that easily convert to yttrium oxide at high temperatures, such as yttrium oxide, and europium oxide h (Ell, 03)
Alternatively, carbonates, nitrates, and other europium compounds that easily convert into europium oxide at high temperatures can be mixed using a physical method such as a ball mill, and this raw material mixture can be fired in a closed atmosphere. Europium, an activator, is homogeneously dispersed to improve luminous efficiency.
It can also be obtained by combining the Jili raw materials chemically (t・ζ).

That is, yttrium oxide and europium oxide are dissolved in hydrochloric acid or nitric acid, and 'fA is added to this solution.
Yttrium 11 by adding acid or dimethyl oxalate aqueous solution
Co-precipitated oxalic acid + 1 precipitate of 2~Robiut was produced, and then this coprecipitated oxalic acid tiNrt, 42r sludge was overdried, and then thermally decomposed at a temperature of 800~1100°C in air to yield Yl.
? + synthesized into a secondary oxide, and further calcined this raw material mixture α') at a temperature of 1200 to 1500"C in 1 V air.
By filtering, a phosphor having the same composition as the mixed m-earth oxide is obtained.

Composition of this rare hepta-oxide phosphor +! ”: (Y+-8,
Eux) to, (10', <x<2X 10-
) is preferable, and if the value of X exceeds 2
, t-1'4L < θft is not good.

In recent years, improving the brightness of `R7 lamps (for cathode ray tubes and lighting) has been a major issue in the industry, and it is desired to improve the brightness of phosphors for general use.

(Objective of the Invention) The present invention provides an improved manufacturing method for obtaining a europium-activated yttrium oxide phosphor with improved luminescence properties that satisfies the above requirements. With the goal.

(Summary of the Invention) The present inventors have developed a europium-activated yttrium oxide phosphor for the purpose of developing a phosphor with high efficiency under 4F and ultraviolet radiation excitation. As a result of repeated research on using a flux, it was discovered that the objective could be achieved by adding barium C borate as a flux and firing, and this invention was completed.

That is, the present invention provides a method for producing a europium-activated yttrium oxide phosphor by firing a raw material mixture.
This is a method for producing a europium-activated yttrium oxide phosphor, characterized in that the raw N mixture contains 3 barium borate.

Europium activated oxide obtained by the present invention) I
The Jium phosphor has a luminous efficiency of 1-8% under electron beam excitation and 0.5-3% pure excitation. Even when the concentration of u, 0.) is exceeded, it has a very sharp effect with high efficiency. It is preferable that the proportion of di- and baloboric acid contained in the raw material mixture is 0.0010, s to 1 centigrade of boron oxide (n, os).

fl, fl 01 ij as boron oxide (o, Os)
I? When barium borate is less than C, the effect of increasing brightness is observed.
5 fj,, It is said that barium borate exceeds Tht') 11; Efficiency is l! : Not only F' J-ru,
Very hard sintered C medium 9 r IIf:t 1. ,
<Naj・),.

(Embodiments of the Invention) The present invention will be described in detail in this embodiment.

Example 1 Yttrium oxide 1. , “f, (i), ) 9.5
Mol and oxide -1--1'+pium (f bow u, 0.)
11.5 mol of the mixture was added to the nitric acid solution 2()p and thoroughly stirred to completely dissolve it. Next, 13 moles of oxalic acid was added to form a coprecipitated oxalate of yttrium and n-11bium. This rL#: Thoroughly washed with one part of acid and one part of acid, further filtered and dried, and then thermally decomposed in air at a temperature of 900°C to obtain rare earth oxide gold containing crystals of yttrium and europium. This [1] was also analyzed in the chamber fluid for yttrium and europium, which are rare earth oxides.
It was confirmed that the composition was oo5, ('+ IIn, o5)t(1*).

Next, 200 grams each of the mixed rare earth oxides of yttrium and europium J. were weighed and prepared.
0.0005゜0 as boron oxide (B, 0,)
．． 001, tl, 005, 0.01. , 0.0
3, 0.05, (1,1,0,5,1,,0,i
,, Barium tetraborate (Ha), which is part of 511j1
11. (,)7) are weighed and added (17), and thoroughly mixed in a ball mill. This mixture was put into a quartz crucible with a lid and placed in the air for 130 min.
Bake for 5 hours at a temperature of 0°0.

On the other hand, as a comparative product, 200 grams of the rt4 total rare earth oxides of yttrium and europium containing no barium tetraborate were placed in a quartz crucible with a lid, and fired in air at a temperature of 1300°0 for 5 hours as described above. do.

The baked product (a-ei) was crushed in a mortar to yield U 100
Metsunyu e song+! Moon-7, after thorough washing with hot water Vr'-C, filter drying and further 10
Y1 brightness, electron beam positive fiiTh +#f, pressure 6KVIj
Relative origin that dies on the 7th rise) ゛C7 bright rs: (t gY value.

I felt empty.

The results are shown in Table 1.

According to Table 1, the excitation brightness of ultraviolet rays 254n+n is H,03 for the comparative product, and -C is 1 @ 000.
Adding 5% has no effect, but adding 01 to 0.5% (January)
The brightness improvement of 1 to 8 inches was announced in Jll, 0.0 :(
% addition showed an 8% improvement in 7iψ height. However, when the additive liquid exceeded 10%, the brightness was lower than that of the comparative product, and at the same time, the product was sintered extremely hard.

On the other hand, 'core wire 61 (V excitation brightness is CB compared to the comparative product,
03 as weight -1*i 61j+), addition of less than 001% is not effective, but addition of 0.05 to 0.5% brightness direction of 0.5 to 3% is recognized, 1) When o3 coefficient was added, the highest value was shown towards the third coefficient. Only 1~Additionally 1.0
4 or higher, the brightness decreased in the same way as the ultraviolet 254n+n excitation brightness.

Example 2 In order to confirm the effect of the phosphor of the present invention in which the concentration of europium oxide (B u 203 ), which is an activator, was varied, (' Iu 9
r, ,I幀f1.05)deOs + (YO,96+
”uo, 04 ) convex + (Yo, 963 + ”'0
．． 035) 3 types with the composition of ToH■ I +14
It rare earth oxide f: Obtained.

Next is the mixed dilute heptad oxidation of yttrium and europium! The proboscis was sewn with 1L5 (Durham scale stitch), and as boron oxide (B, 011), it was 0.03 times i21 times.
Barium tetraborate (B; l 1140.) was weighed [71. After thorough testing in a ball mill, the mixture is poured into a quartz crucible with a lid.

On the other hand, as a comparison product, 5 (lf) grams of each of three kinds of mixed rare earth oxides (C1 tetraborate barium, human-C) were put into a quartz crucible with a lid, and both were simultaneously placed in the air for 13 ( Fire at a temperature of 10°C for 5 hours.Furthermore, each of the fired products'f:!L is crushed in a mortar and passed through a 100 mesh. It's already past 11.

The europium of the present invention obtained in Example L, the activated yttrium 11cetate fluorescein (16) and the phosphor for specific axis (b) were subjected to relative emission by ultraviolet rays of 254 nm lil) in the same manner as in Example J). 1 (The results of evaluating and comparing the relative emission brightness between S brightness and electron beam anode fE6KV excitation are 0-1.) The second aspect of the present invention is mono-robium activated yttrium oxide 911. Barium (Ba) in the light body, The results of Rule 4 analysis of boron (13) in one row are shown in Table 2.

As shown in Table 2, this is
J clearing H9 version Eurobiuno, (E audience (+, )
p 19-♀' (C for the ratio-11Q product even in the changed Meikai
, ultraviolet ray') at 54 nm excitation brightness +(, (1~!1
．． 3% brightness 1r (direction) - 1+'lt I'ili:i
! 6f< V bil no 4HIl 'c2.4~:
4.0% 118B HttH 1 k ffJ i
, = . 'I'! Ultraviolet light 254 nm li for Y, II
rlj; Luminance E'l'> Ite & j glare "A'+ F
]'::,'Valency 1 m 71-1-1 [Gobium (E
+12”M) to i1.(1!'1 mole or r) il
, fl: (5〔LETO: 10G・Reduced H, 7t Sasuta Ning r
c c also acid f);, - Robiul, old) 5 mol of a light L -11=E invention 31 disorder) 1t fk t
, l: 7 Chi no Hikaru 1 rt Niko 1: U; 1 (Abira JL, departure) + (, efficiency t,') 1 clear f want 1 mourning 11 -
1-- Iffff flyer 1; 1 active f'+W conversion 1.
+)y /, Km)Y; f book C, is le C and f4t. fx, I';・uninvented fireflies) out of 41 bodies (,゛) Bali 1゛ano, (11), -1 (Tsu element fnl 2 constant analysis (7 results fxha, f-':?t 2 D1
1 ppm J,! ; Nodo + , 1110 p p
m or more including r1. , F Irokoto gave an edict.

Claims (2)

[Claims] (1) Using a method of firing a raw material mixture to form a europium-activated yttrium oxide phosphor,
A method for producing a europium-activated yttrium oxide phosphor, characterized in that the raw material mixture contains barium borate. (2) Boron oxide (yO*) and li',
Claims 1 and 2 are characterized in that they contain the barium borate in a proportion of 1 to 1. Closed europium consists of 16 l111 (active yttrium oxide band)
! Law method.