JPS6330585A - Silicate phosphor - Google Patents

Abstract

PURPOSE:To improve the initial deterioration of the brightness and afterglow, by incorporating a particular trivalent element and a particular pentavalent element in predetermined amounts in a silicate phosphor contg. manganese as an activator. CONSTITUTION:A particular trivalent element and a particular pentavalent element are incorporated in a silicate phosphor contg. manganese as an activa tor. The trivalent element is indium or a combination of indium and boron, while the pentavalent element is at least one member selected from among arsenic, antimony, and bismuth. The trivalent element content is 1X10<-4>-2X10<-2> g-atom/mol, provided that the content is 1X10<-4>-1X10<-2> g-atom/mol when the trivalent element consists of only indium. The pentavalent element content is 3X10<-3> g-atom/mol or less, and the molar ratio of the trivalent element to the pentavalent element is 1.5 or more, thus according the aimed silicate phosphor.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a silicate phosphor containing manganese as an activator, and more particularly, it relates to a silicate phosphor containing manganese as an activator, and more specifically, a specific amount of specific trivalent elements and pentavalent elements. By containing it within a range of the ratio, initial deterioration of brightness and afterglow can be improved, and the phosphor relates to a silicate phosphor.

[Conventional technology]

In recent years, combinations that display detailed characters and figures, -
It is desired to use high-resolution cathode ray tubes in terminal display devices for aircraft, aircraft control system display devices, etc.

The phosphor film of such high-resolution cathode ray tubes often uses a phosphor with long afterglow properties.

In general, the phosphor constituting such a phosphor film has an afterglow time (herein, the time required for the luminance to decrease to 10% of the excitation level after excitation is stopped, that is, the rios afterglow time). It is necessary that the length (supposed to be about 10 to 10 times longer) is longer than the short afterglow phosphor that makes up the entire phosphor film of an ordinary cathode ray tube.

However, as such long afterglow green-emitting zinc silicate phosphors, manganese and arsenic activated zinc silicate phosphors (
P39 phosphor) and manganese-activated zinc silicate phosphor (PT phosphor) are known, and P39 phosphor in particular is in practical use in large quantities.

However, as it has been used for various purposes, many drawbacks have been discovered in terms of brightness, afterglow, deterioration, coating properties, etc., and improvements in these areas have been strongly desired. Kutoe is Special Publication No. Sho 57-48594, Japanese Patent Publication No. Sho 58-151
Various compositions have been proposed in publications such as No. 322 and JP-A-59-184281.

However, in general, display tubes made using silicate phosphors containing manganese as an activator display the same 9 turns on the tube surface for several to tens of hours after manufacture, and the display tubes display the same 9 turns on the tube surface for several to tens of hours, such as adjusting the IJ nearness, etc. Initial adjustments are made.

In a conventional phosphor film using a silicate phosphor, as shown above, when exposed to electron beam irradiation, the afterglow is shorter (initial afterglow deterioration) and the brightness is reduced compared to the area that is not exposed to electron beam irradiation. However, there were some disadvantages such as the following (initial brightness deterioration). This makes the initial adjustment of display tubes complicated, requiring many cathode ray tubes to be knee-song for a long time, and subsequent deterioration is difficult to predict. This process causes various problems, such as difficulty in setting up each circuit of the product, the initial adjustment pattern remaining on the screen due to brightness deterioration, and flickering in the core due to partial afterglow deterioration. was there.

[Problem that the invention seeks to solve]

An object of the present invention is to provide a silicate phosphor containing manganese as an activator, which can significantly improve initial afterglow deterioration and initial brightness deterioration under excitation with an electron beam or the like.

The present inventors conducted various studies on traps and silicate phosphors in order to achieve the above objectives, and as a result, they identified a specific trivalent element in silicate phosphors containing manganese as an activator. When the pentavalent element is contained in a specific molar ratio,
The inventors have discovered that the above-mentioned deterioration can be significantly improved, leading to the present invention.

In addition, the above-mentioned 3.
Although a 7'hP39 phosphor containing equal moles of valent and pentavalent elements has been disclosed, the present inventors have found that the above problem can be solved by using a different quantitative ratio. .

The silicate phosphor of the present invention is a silicate phosphor containing manganese as an activator and containing trivalent and pentavalent elements.
The trivalent element is indium or boron and insium, and the pentavalent element is at least one of arsenic, antimony, and bismuth.
seeds, and the content of the trivalent element is 1 x 10 to 2 x 10
1 mol of gram atom, if the trivalent metal is only indium, 1 x 10 to 1 x 10 gram atom, 1 mol of the pentavalent element, the content of the pentavalent element is 1 mol or less of 3 x 10 gram atoms, and the above It is characterized in that the molar ratio of the content of trivalent and pentavalent elements (trivalent element to 15valent element) is 1.5 or more.

The most typical silicate phosphor containing manganese as an activator is a manganese-activated zinc silicate-based phosphor, but there are also manganese-activated magnesium silicate-based phosphors. There are divalent metal cation silicate phosphors such as phosphors, manganese and lead activated calcium silicate phosphors.

Hereinafter, the present invention will be explained in detail based on the most typical method for producing a manganese-activated zinc silicate-based phosphor.

First, the raw materials for the phosphor include 1) Zinc compounds that can be easily converted to Zoo at high temperatures, such as zinc oxide (ZnO), carbonates, and oxalates; 11) Silicon dioxide (SiO□), ethyl silicate, and silicic acid, which can be easily converted to Zoo at high temperatures. Silicon compounds that can be converted into 810□ri) Manganese oxide (Mn02) or manganese compounds that can be converted to manganese oxides at high temperatures, such as metal manganese, carbonates, nitrides, sulfides, etc.iv) Indium and boron oxides or compounds of indium and boron that can be easily converted into oxides of indium and boron at high temperatures V) Oxides or metals of arsenic, antimony and bismuth, heronides etc. Arsenic, antimony and bismuth can be converted into oxides of arsenic, antimony and bismuth, and their compounds are used.

The above-mentioned phosphor raw materials are weighed out and then thoroughly mixed to obtain a phosphor raw material mixture. Mixing is done using Gale mill, mixer mill,
It may be carried out in a dry manner using a mortar or the like, or it may be carried out in a wet manner using water, alcohol, weak acid, etc. as a medium and in a coated state. A flux may be further added to the phosphor raw material mixture for the purpose of improving the luminance, powder properties, etc. of the obtained phosphor.

It should be noted that among the above raw materials i.sub.1) and .2), when fired at high temperatures, some of them tend to volatilize, so they are added slightly longer depending on the firing temperature, time, etc.

Next, mix the above phosphor material mixture into an alumina crucible or a quartz crucible. Fill it in a heat-resistant container such as , etc., and perform baking. Firing is carried out at 1000°C to 1350°C in air (oxidizing atmosphere), in a neutral atmosphere such as a nitrogen gas atmosphere or argon gas atmosphere, or in a reducing atmosphere such as a nitrogen gas atmosphere containing a small amount of hydrogen gas or a carbon atmosphere. , preferably from 1200°C
This is carried out once or several times (3 to 4 times) at a temperature of 1300°C.

Further, even better results can be obtained if the base material of the phosphor is pre-sintered at 500 DEG C. to 1300 DEG C. and the grain size of the base material is grown.

The firing time varies depending on the size of the phosphor raw material mixture filled in the heat-resistant container, the firing temperature employed, etc., but in general, 0.5 to 6 hours is appropriate in the above firing temperature range, and 1 to 6 hours.
4 hours is preferred. After firing, the fired product obtained is subjected to various operations generally employed in the field of phosphor manufacturing, such as crushing, washing (this may be done with water, weak mineral acids, weak alkalis, weak organic acids, etc.), drying, and sieving. After processing, the phosphor of the present invention can be obtained.

The thus obtained phosphor of the present invention and the conventional zinc silicate phosphor (P39) are each applied uniformly onto a glass plate by a precipitation coating method to form a phosphor film, and a tube is manufactured. Display tubes were manufactured according to the method, and the emission intensity deterioration characteristics due to continuous excitation of the fluorescent surface were measured using each display tube. The results are shown in FIG.

According to the figure, it is clear that the zinc silicate phosphor of the present invention has significantly better luminous intensity deterioration characteristics than conventional products.

Next, Table 1 shows the results of measuring afterglow deterioration characteristics.
It is clear that the zinc silicate phosphor of the present invention has better afterglow deterioration characteristics than conventional products.

Table 1 Figure 2 shows the relationship between initial afterglow deterioration characteristics and indium content. Figure 3 shows the arsenic content and 1 when the contents of indium and antimony are constant, and when the contents of indium, boron, and antimony are constant.
Figure 4 shows the relationship between the 710 afterglow time and afterglow deterioration characteristics, and shows the relationship between the indium content and relative brightness when the only trivalent element is indium. However, if a large amount of indium is added, the relative brightness will drop significantly, which is not preferable. Therefore, the appropriate content of indium is in the range of 1 x lO to I
A range of X10 gram atom to 1 mole is recommended.

According to the above graph, the content of the element 3filfi is 1
×10 to 2 × 10 1 mole of gram atom, if the only trivalent element is indium, 1 × 10 to 1 × 10 1 mol of gram atom, 3 × 10 if the pentavalent element is 1 mole or less of gram atom, trivalent and the molar ratio of the content of pentavalent elements (trivalent element 15
It is appropriate that the valence element) be 1.5 or more. In addition,
The upper limit of the above molar ratio is 500 if the pentavalent element is arsenic only.
, and when the pentavalent element is at least one of antimony and bismuth, it is appropriate to set it to 50.

Examples will be explained below, and the test method for B7 will be described first.

Measuring method using a demountable device: (a) Preparation of test piece A 2.5 x 3 cm test piece is coated with the phosphor to be inspected by a precipitation method to form a fluorescent film.

(b) Electron beam irradiation The above test piece was set in a demountable electron beam stimulator (manufactured by our company) at an acceleration voltage of 20 kV and a current density of 1 μA.
/Return 2, irradiate with electron beam for 20 minutes at raster size 1X1cjn.

(c) Luminance measurement During the above electron beam irradiation, the luminance was measured at 1 minute intervals using a luminance meter.

b) Afterglow measurement Measure the 1/10 afterglow time under the following conditions before and after electron beam irradiation.

It is excited with an undeflected defocused beam with an accelerating voltage of 15 kV, a z4 pulse width of 102.4 ms, and a duty of 50%. Current density was 0.5 μA/cIR.

Example 1 Zinc oxide ZnO370,9 silicon dioxide
sto2tsog carbonic acid-r-ngan MnCO5・0
．． 5 B20 2-59 Indium trioxide In2O3
1,'1 Arsenic trioxide As 20s o-
o s E antimony trioxide 5b2o,
o, s, p The above raw materials were sufficiently pulverized and mixed in a dry ♂-lumil, filled into a quartz crucible, and fired in air at 1300°C for 4 hours. The composition formula was Zn23104: Mu
0.00 B, In0.003・A'O,0OO1
1sbo, ooi's phosphor of the present invention.

The luminous intensity maintenance rate of this phosphor is 99%, ensuring no afterglow deterioration.

Conventional phosphor (Zn28104: Mno, o o s
, As O, 0001) has an emission intensity maintenance rate of 941 ft.

Example 2 Zinc oxide Zn0 390g Silicon dioxide sio□ 150g Manganese carbonate MnCO3-05H201,5,9 Indium trisulfide I! 1203 o-5Ji' boron tridisperse B20. 0.25. ! i
'E element trioxide A a 20s O
-059 Antimony trioxide 5b20. 1
g The above raw materials were sufficiently ground and mixed in a dry type gold mill, filled into a quartz crucible, and fired in air at 1300°C for 4 hours.
.

InO,OOl,Bo,003#AIO,0O01l5
A phosphor of the present invention of bO,002 was obtained.

The luminescence intensity maintenance rate was 99% and there was no afterglow deterioration.

Conventional phosphors had a luminescence intensity maintenance rate of 94%.

Example 3 Zinc oxide ZnO 390g Silicon dioxide 8102150g Manganese carbonate
MIICO3・05H202,5,! il indium trioxide 203 1.99 antimoy trioxide y 5b2o30.5.p The above raw materials were thoroughly ground and mixed in a dry sol mill, filled into a quartz crucible,
After firing in air at 0℃ for 4 hours, the composition formula was Zn.
2 S i 04: Nagi Q, 008-I”0.00
3. A phosphor of the present invention with Sb of 0.001 was obtained.

The luminescence intensity maintenance rate was 99 cm, and there was no afterglow deterioration.

By the way, the conventional fluorescent material (zn2S104: Mno, o
o s ) has a luminous intensity maintenance rate of 93chi, which is a good thing.

Example 4 Zinc oxide ZnO370, ji' silicon dioxide 51021501! Carbonic acid MnCO
3-05H202,5F Indium trioxide In2O
,0,69 Borax Na2B4O7' l0
H202,1ji E element trioxide A3□030.
099 Antimony trioxide 5b 2030.5g The above raw materials were sufficiently ground and mixed with a dry sol and filled into a quartz bolt.
After firing at 1300°C in 4br air, the compositional formula was Zh23104:Mn□,00B, taO,001
゜Bo, 006 IAl), 0002 Snow Sb O, 001
The phosphor of the present invention is obtained.

The luminescence intensity maintenance rate was 99%, and afterglow deterioration was significant.

Conventional phosphors have a luminous intensity maintenance rate of 94 cm.

Example 5 Brewed zinc ZnO390,p silicon dioxide
sto□ 150g manganese carbonate
This co3・o, 5H2o 2.5J indium trioxide "20s 0.6ji arsenic trioxide
”203 0.05.9 above original'prt
-Dry method? - Thoroughly pulverized and mixed in Lumil, filled in a quartz crucible, and fired in air at 1300°C for 4 hours.
, 001, As o, o 001, the phosphor of the present invention was obtained.

The luminescence intensity maintenance rate was 99 cm, and there was no afterglow deterioration. By the way, the composition formula Zn25IO4: ? V! n O,00B
, As0.0001 phosphor has a luminescence intensity maintenance rate of 9
It's 4chi.

〔Effect of the invention〕

As described above, according to the present invention, a silicate phosphor containing manganese as an activator contains a specific trivalent element and a pentavalent element in a specific quantitative ratio. Initial deterioration of brightness and afterglow can be significantly improved.

[Brief explanation of drawings]

FIG. 1 is a graph showing the luminescence intensity deterioration characteristics comparing the silicate phosphor of the present invention with that of a conventional one. FIG. 2 is a graph showing the relationship between the initial afterglow deterioration characteristics and the indium content. Figure 3 shows the relationship between the arsenic content and the 1/10 afterglow time and afterglow deterioration characteristics when the contents of indium and antimony are kept constant, and when the contents of indium, boron, and antimony are kept constant. The graph shown in FIG. 4 is a graph showing the relationship between the indium content and relative brightness when indium is the only trivalent element. Procedural amendment October 15, 1988 Commissioner of the Japan Patent Office Black 1) Yu Akira 1, Indication of the case Japanese Patent Application No. 172881/1981 2, Name of the invention silicate phosphor 3, Person making the amendment Relationship to the case Patent applicant name: Kasei Obtonics Co., Ltd. 4, agent address: 6, Mori Building, 40 Toranomon, 5-13-1, Toranomon, Minato-ku, Tokyo Contents of amendment (1) Described on pages 1 to 3 of the specification The scope of claims is amended as shown in the attached sheet. (2) In the fourth line of page 4 of the same book, the text "NO% afterglow time" is corrected to "r 1/10 afterglow time". (3) In the same book, page 6, line 16, the phrase "indium, which is pentavalent" is corrected to "indium, which is pentavalent." (4) In the same book, page 6, line 19, "trivalent metal" is corrected to "trivalent element." (5) Figure 1 of the drawings should be corrected as shown in the attached sheet. Claims (1) A silicate phosphor containing manganese as an activator and containing a trivalent element and a pentavalent element. the trivalent element is indium or indium and boron;
The trivalent element is at least one of arsenic, antimony, and bismuth, and the content of the trivalent element is lXl0-4
~ I and the molar ratio of the contents of the trivalent and pentavalent elements (trivalent element and 15valent element) is 1.5.
A silicate phosphor characterized by the above: (2) a silicate phosphor according to claim 1, characterized in that the content of arsenic is 1 mole or less of lXl0-3 gram atoms; (3) When the content of the trivalent element is indium and boron, it is in the range of lXl0-3 to lXl0-2 gram atom 1 mol, and in the case of indium alone, it is in the range of 2X10-4 to 5XIO-3 gram atom 1 mol. The silicate phosphor according to claim 1 or 2, characterized in that the molar ratio (trivalent element to 15-valent element) is 1.8 or more: (4) the molar content of the above content; Ratio (trivalent element to 15valent element)
is 1.8 or more, the silicate phosphor according to claim 1 or 2, wherein: (5) the pentavalent element is only arsenic; (8) The silicate phosphor according to any one of claims 1 to 4, characterized in that the molar ratio of the content (trivalent element and 15-valent element) is 5 or more. Arsenic content is lXl0-4 to 8x10-4
The silicate phosphor according to any one of claims 2 to 5, characterized in that the activation amount of the manganese is in the range of 1 mole of gram atom:
The silicate phosphor according to any one of claims 1 to 6, characterized in that the activation amount of the manganese is in the range of 2×10 −3 to 1 mole. l×10
A silicate phosphor according to claim 7, characterized in that the silicate phosphor is in the range of -2 gram atoms per mole:

Claims (8)

[Claims] (1) Contains manganese as an activator and contains trivalent elements and 5
In the silicate phosphor containing a valent element, the trivalent element is indium or indium and boron, the pentavalent element is at least one of arsenic, antimony, and bismuth, and the trivalent element is at least one of arsenic, antimony, and bismuth. Content is 1x10^-^4~2x
10^-^2 gram atoms/mol, if the trivalent metal is indium only, 1 x 10^-^4 to 1 x 10^-^2 gram atoms/mol, the content of the pentavalent element is 3 ×10＾−
^3 gram atom/mol or less, and a silicate characterized in that the molar ratio of the content of the trivalent and pentavalent elements (trivalent element/pentavalent element) is 1.5 or more. Fluorescent material: (2) The silicate phosphor according to claim 1, wherein the content of arsenic is 1×10^-^3 gram atoms/mol or less: (3) When the content of the trivalent elements is indium and boron, it is 1 x 10^-^3 to 1 x 10^-^2 gram atom/
Mole range: 2×10^-^4 to 5 for indium only
×10^-^3 gram atom/mole, and the molar ratio (trivalent element/pentavalent element) is 1.8 or more, according to claim 1 or 2. Silicate phosphor: (4) The silicate according to claim 1 or 2, wherein the molar ratio of the content (trivalent element/pentavalent element) is 1.8 or more. Fluorescent material: (5) Claim 1, wherein the pentavalent element is only arsenic, and the molar ratio of the content (trivalent element/pentavalent element) is 5 or more. or fourth
The silicate phosphor according to any of the paragraphs: (6) The arsenic content is 1 x 10^-^4 to 8 x 1
A silicate phosphor according to any one of claims 2 to 5, characterized in that the silicate phosphor is in the range of 0^-^4 gram atoms/mole: (7) The activation amount of the manganese is 1×10^-^3~3
A silicate phosphor according to any one of claims 1 to 6, characterized in that the phosphor is in the range of x10^-^2 gram atoms/mole: (8) The activation amount of the manganese is 2×10^-^3~1
A silicate phosphor according to claim 7, characterized in that it is in the range of x10^-^2 gram atoms/mole: