CA1132791A - Zinc sulfide phosphor coactivated with gold, copper and aluminum - Google Patents
Zinc sulfide phosphor coactivated with gold, copper and aluminumInfo
- Publication number
- CA1132791A CA1132791A CA317,236A CA317236A CA1132791A CA 1132791 A CA1132791 A CA 1132791A CA 317236 A CA317236 A CA 317236A CA 1132791 A CA1132791 A CA 1132791A
- Authority
- CA
- Canada
- Prior art keywords
- copper
- aluminum
- gold
- zinc sulfide
- mix
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
- C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
- C09K11/64—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing aluminium
- C09K11/641—Chalcogenides
- C09K11/642—Chalcogenides with zinc or cadmium
Abstract
ZINC SULFIDE PHOSPHOR COACTIVATED
WITH GOLD, COPPER AND ALUMINUM
ABSTRACT OF THE DISCLOSURE
The addition of gold as an activator to a zinc sulfide phosphor coactivated by copper and aluminum results in color coordinate shifts of cathodoluminescent emissions to higher x values, enabling use, for example, as a replacement for the zinc cadmium sulfide green phosphor activated by copper and aluminum presently used in color cathode ray tubes for color television.
WITH GOLD, COPPER AND ALUMINUM
ABSTRACT OF THE DISCLOSURE
The addition of gold as an activator to a zinc sulfide phosphor coactivated by copper and aluminum results in color coordinate shifts of cathodoluminescent emissions to higher x values, enabling use, for example, as a replacement for the zinc cadmium sulfide green phosphor activated by copper and aluminum presently used in color cathode ray tubes for color television.
Description
i --~;Z79~
BACXGROUND OF THE INVENTION
-This invention relates to zinc sulfide phosphors, and more particularly relates to zinc suIfide cathodoluminescent phosphors coactivated by gold, copper and aluminum.
A standard green phosphor used widely in the production of cathode ray tubes for color television is a zinc cadmium sulfide coactivated with copper and aluminum. The presence of cadmium in these phosphors is known to have certain beneficial effects. For example, the amount o cadmium may be adjusted to vary x and y coordinate values within a permissible range. Nevertheless its cost and handling pre-cautions could lead eventually to the use of cadmium-free cathode ray tube phosphors. Furthermore, phosphors contain-ing cadmium tend to exhibit yellow body coLor and undesirable shifts in body color during processing, so called "bake shifts".
While zinc sulfide phosphors coactivated with copper and aluminum having green cathodoluminescent emissions have been known for some time, (see for example, U.S. Patent 2,623,858, issued to Kroger on December 30, 1952), such phosphors are characterized by low brightness levels and by the presence of significant blue emissions, relulting in low purity of green emissions. Such characteristics~render these phosphors unsuitable for use in conventional tri-dot color cathode ray tubes for color television.
In United StatesPatent 4,038,205, issued to ~enry B.
Minnier and H. David Layman on JuIy 26, 1977, and assigned to the present assignee, a critical firing process is claimed whereby the green emitting zinc sulfide: copper, aluminum phosphor is improved in both color purity (by the substantial suppression of blue emissions) and brightness, rending such phosphors candidates for replacement of the present zinc~
cadmium sulfide: copper, aluminum phosphors in color cathode ray tubes. ~
~3Z7~1 It h~5 been discoye~ed th~t the ~ddition o~ yold as as ~n acti~ator to ~ zinc sul~ide phosphox coactivated with copper and aluminum results in cathodoluminescent emissions having color cooxdina.tes shi~ted to higher ~ values, enabling consideration o such phosphors as cand.idates fox xeplace-ment o the zinc~cadmium sulfide- copper, aluminum green phosphor in colox cathode ray tu~es ~or colox television.
As used herein the terms "x" and "y" coordinate values refer to values on a standard chromaticity diagram as de~ined by CIE ~Commission InternationaIe de L'Elairaje~
as determined by impinyement of a cathode ray heam upon a packed sample of thQ phosphor po~der.
According to the present invention, there is provided a 2inc sulfide cathodoluminescent phosphor coactivated by gold, copper and aluminum, said gold, copper and aluminum being present in the ranges of about 350 to 550 parts per million/ 50 to 150 and 300 to 600 parts per million respect-ivel~, and wherein the phosphor upon cathodoluminescent emission exhibits x and y coordinate values within the range o .3~0 to ~345 and .570 to .580 respectively.
Some embodiments of the invention will now be described with reference to the examples belo~:
It is essential for the achievement of the advantages described herein that the zinc sulfide phosphor contain all three coactivators and may vary over a broad range, the a~lount of gold typicall~ ranging from 20 to 900 parts per million, copper from 50 to 250 parts per million and aluminum from 200 to 1,000 parts per million. However,it ls in general preferred for the green component of a tri-dot color cathode ray tube for color television to maintain the activa-3q tor le~els within the ranges o 35~ to 550 parts per million gold, 50 to 150 parts per million copper and 300 to 600 parts per million alurl~inum, resultiny in x and ~ coordinate values 'J, within the range of .3~0 to 34$ and .570 to .580 respectivel~.
~ ~ 3zt~9 ~
Specific combinations of Au, Cu and Al which will result in desired x and y coordinate values may be determined by reference to the following regression analysis equations for x and y as a function of Xl, X2 and X3, where:
Xl =(ppm Au -600) X =(ppm Al/27)
BACXGROUND OF THE INVENTION
-This invention relates to zinc sulfide phosphors, and more particularly relates to zinc suIfide cathodoluminescent phosphors coactivated by gold, copper and aluminum.
A standard green phosphor used widely in the production of cathode ray tubes for color television is a zinc cadmium sulfide coactivated with copper and aluminum. The presence of cadmium in these phosphors is known to have certain beneficial effects. For example, the amount o cadmium may be adjusted to vary x and y coordinate values within a permissible range. Nevertheless its cost and handling pre-cautions could lead eventually to the use of cadmium-free cathode ray tube phosphors. Furthermore, phosphors contain-ing cadmium tend to exhibit yellow body coLor and undesirable shifts in body color during processing, so called "bake shifts".
While zinc sulfide phosphors coactivated with copper and aluminum having green cathodoluminescent emissions have been known for some time, (see for example, U.S. Patent 2,623,858, issued to Kroger on December 30, 1952), such phosphors are characterized by low brightness levels and by the presence of significant blue emissions, relulting in low purity of green emissions. Such characteristics~render these phosphors unsuitable for use in conventional tri-dot color cathode ray tubes for color television.
In United StatesPatent 4,038,205, issued to ~enry B.
Minnier and H. David Layman on JuIy 26, 1977, and assigned to the present assignee, a critical firing process is claimed whereby the green emitting zinc sulfide: copper, aluminum phosphor is improved in both color purity (by the substantial suppression of blue emissions) and brightness, rending such phosphors candidates for replacement of the present zinc~
cadmium sulfide: copper, aluminum phosphors in color cathode ray tubes. ~
~3Z7~1 It h~5 been discoye~ed th~t the ~ddition o~ yold as as ~n acti~ator to ~ zinc sul~ide phosphox coactivated with copper and aluminum results in cathodoluminescent emissions having color cooxdina.tes shi~ted to higher ~ values, enabling consideration o such phosphors as cand.idates fox xeplace-ment o the zinc~cadmium sulfide- copper, aluminum green phosphor in colox cathode ray tu~es ~or colox television.
As used herein the terms "x" and "y" coordinate values refer to values on a standard chromaticity diagram as de~ined by CIE ~Commission InternationaIe de L'Elairaje~
as determined by impinyement of a cathode ray heam upon a packed sample of thQ phosphor po~der.
According to the present invention, there is provided a 2inc sulfide cathodoluminescent phosphor coactivated by gold, copper and aluminum, said gold, copper and aluminum being present in the ranges of about 350 to 550 parts per million/ 50 to 150 and 300 to 600 parts per million respect-ivel~, and wherein the phosphor upon cathodoluminescent emission exhibits x and y coordinate values within the range o .3~0 to ~345 and .570 to .580 respectively.
Some embodiments of the invention will now be described with reference to the examples belo~:
It is essential for the achievement of the advantages described herein that the zinc sulfide phosphor contain all three coactivators and may vary over a broad range, the a~lount of gold typicall~ ranging from 20 to 900 parts per million, copper from 50 to 250 parts per million and aluminum from 200 to 1,000 parts per million. However,it ls in general preferred for the green component of a tri-dot color cathode ray tube for color television to maintain the activa-3q tor le~els within the ranges o 35~ to 550 parts per million gold, 50 to 150 parts per million copper and 300 to 600 parts per million alurl~inum, resultiny in x and ~ coordinate values 'J, within the range of .3~0 to 34$ and .570 to .580 respectivel~.
~ ~ 3zt~9 ~
Specific combinations of Au, Cu and Al which will result in desired x and y coordinate values may be determined by reference to the following regression analysis equations for x and y as a function of Xl, X2 and X3, where:
Xl =(ppm Au -600) X =(ppm Al/27)
2(ppm Au + ppm Cu) X =(ppm Cu -150)
3 50 The equations are as follows:
(1) x = 0.2662 -0.0013Xl +0.0162X2 +0 .00459X3 -0.0005X12 -O . 00043X22 -O . 00187X32 ~0.00297~1X2 -0.00274XlX3 -O.00187X2X3 (2) y = 0.606 -0.00057Xl -0.00235X2 +0.00496X3 -0.00027XlX2 -0.00017XlX3 -0.000495X2X3 ~0.000137Xl -0.000139X2 -O.00332X32 While the preparation of the phosphors of the invention can be by any conventional method known in the art, in order to aid the practitioner, an exemplary preparatory technique will now be described.
Zinc sulfide, made by bubbling H2S gas through a solu-tion of zinc sulfate, is dry blended with sources of gold, copper and aluminum in the desired levels. Such sources of activators include by way of example nitrates, carbonates, sulfates, sulfides, chlorides and bromides. A flux of an alkali metal hallde or alkaline earth metal halide, usually the chloride or bromlde, and optionally sulfur, is added to the blend and the mixture is then fired under a CS2 astmos-phere at a temperature ~3279~
within the range of about 950 to 1050C for a time of from about 1 to 2 hours, and then allowed to cool. The flux is removed by washing and the powder is dried. Color and brightness of the powder are then read on a packed bed of the powder subjected to 14 kilovolt cathode rays.
The following are specific examples of the above process.
In all cases, the activators were introduced as a "mix"
prepared as follows:
Gold sulfide was prepared by dissolving chloroauric acid trihydrate in water, adding zinc sulfide powder, and bubbling H2S gas through the solution so as to yield a mixed sulfide containing about 1500 parts per million of gold by weiqht (gold mix).
Zinc sulfide powder was added to copper sulfate solution and processed the same as the gold mix so as to yield a mix containing about 5,000 parts per million of copper by weight (copper mix).
Zinc sulfide and aluminum chloride were slurried in water and the slurry was evaporated to dryness. The result-ing zinc sulfide contained about lC,000 parts per million of aluminum by weLght (aluminum mix).
-EXAMPLE I
To 47.2 grams of zinc sulfide, 0.9 grams of gold mix, 1.28 grams of aluminum mix and 0.64 grams of copper mix were added, corresponding to levels of these activators in parts per million of 27 gold, 64 copper, and 256 aluminum.
Two grams of a flux mix in the ratio of 90 parts by weight sulfur and 30 parts by weight potassium bromLde were added to the mixture andthe mixture was blended. It was then placed in a quartz tray and flred for about 2~ hours at about 1850F under a flowing CS2 atmosphere. The powder was then cooled and washed to remove soluble flux, followed ~y drying. The resulting sal-~le was formed into a packed bed and subjected to 14~V cathode rays and the color coordinates and brightness were measured vs. a standard zinc-~3Z79~
cadmium sulfide coactivated with copper and aluminum in the amoun~s of about 50 parts per million copper and 100 parts per million aluminum. The m~lar ratio of zinc to cadmium in the standard was 14.45:1. The standard had x and y coordinate values of 0.340 and 0.595 respectively and was assigned a brightness level of 100 percent. The sample pro-duced x and y coordinate values of 0.271 and 0.557 respect-ively and a brightness of 91 percent.
EXAMPLE II
The procedure of Example I was repeated except that 41.38 grams of zinc sulfide were mixed with 6.7 grams of gold mix, 1.28 grams of aluminum mix and 0.64 grams of copper mix, corresponding to levels of activators in parts per million of 200 gold, 64 copper and 256 aluminum. This sample yielded x and y coordinate values of 0.291 and 0.573 respectively - ` and a relative brightness of 85 percent of standard.
EXAMPLE III
The procedure of Example I was repeated except that 29.88 grams of zinc sulfide were mixed with 18.2 grams of gold mix, 1.28 grams of alumlnum mix and 0.64 grams of copper mix, corresponding to levels of these actlvators in parts per million of 546 gold, 64 copper and 256 aluminum. This sample yielded x and y coordinate values of 0.307 and 0.573 respectively and a brightness of 77 percent of~standard.
EXAMPLE IV
The procedure of Example I was repeated except that 21.75 grams of zinc sulflde were mixed with 25 grams of gold mix 1.75 grams of aluminum mix and 1.5 grams of copper mix, corresponding to levels of these activators in parts per million of 750 gold, 150 copper and 350 aluminum. The sample yielded x and y coordinate values of 0.299 and 0.5~6 respectively, and a relative brightness of 72 percent of standard.
~L3Z~
EXAMPLE V
The procedure of Example I was repeated except that25.5 gramsof zinc sulfide were mixed with 20 grams of gold mix, 3 grams of aluminum mix and 1.5 grams of copper mix, corres-ponding to levels of these act-vators in parts per million of 600 gold, 150 copper and 600 aluminum. This sample yielded x and y coordinate values of 0.325 and 0.582 respec-tively, and a relative brightness of 70 percent of standard.
EXAMPLE VI
The procedure of Example I was repeated except that 27.75 grams of zinc sulfide were mixed with 20 grams of gold mix, 1.75 grams of aluminum mix and 0.5 grams of copper mix, - corresponding to levels of these activators in parts per million of 600 gold, 50 copper and 350 aluminum. This sample yielded a phosphor with x and y coordinate values of 0.309--and 0.568 respectively in a relative brightness of 76 percent of standard.
The results of these six samples are tabulated below in Table I.
TABLE I
x y Brightness Std. ZnCdS:Al, Cu 340 .595 100 SAMPLE Cu Al Au (in parts per million) 1 64 256 27 .271 .557 91%
2 64 256 200 .291 .573 85 3 64 256 546 .307 .573 77~
(1) x = 0.2662 -0.0013Xl +0.0162X2 +0 .00459X3 -0.0005X12 -O . 00043X22 -O . 00187X32 ~0.00297~1X2 -0.00274XlX3 -O.00187X2X3 (2) y = 0.606 -0.00057Xl -0.00235X2 +0.00496X3 -0.00027XlX2 -0.00017XlX3 -0.000495X2X3 ~0.000137Xl -0.000139X2 -O.00332X32 While the preparation of the phosphors of the invention can be by any conventional method known in the art, in order to aid the practitioner, an exemplary preparatory technique will now be described.
Zinc sulfide, made by bubbling H2S gas through a solu-tion of zinc sulfate, is dry blended with sources of gold, copper and aluminum in the desired levels. Such sources of activators include by way of example nitrates, carbonates, sulfates, sulfides, chlorides and bromides. A flux of an alkali metal hallde or alkaline earth metal halide, usually the chloride or bromlde, and optionally sulfur, is added to the blend and the mixture is then fired under a CS2 astmos-phere at a temperature ~3279~
within the range of about 950 to 1050C for a time of from about 1 to 2 hours, and then allowed to cool. The flux is removed by washing and the powder is dried. Color and brightness of the powder are then read on a packed bed of the powder subjected to 14 kilovolt cathode rays.
The following are specific examples of the above process.
In all cases, the activators were introduced as a "mix"
prepared as follows:
Gold sulfide was prepared by dissolving chloroauric acid trihydrate in water, adding zinc sulfide powder, and bubbling H2S gas through the solution so as to yield a mixed sulfide containing about 1500 parts per million of gold by weiqht (gold mix).
Zinc sulfide powder was added to copper sulfate solution and processed the same as the gold mix so as to yield a mix containing about 5,000 parts per million of copper by weight (copper mix).
Zinc sulfide and aluminum chloride were slurried in water and the slurry was evaporated to dryness. The result-ing zinc sulfide contained about lC,000 parts per million of aluminum by weLght (aluminum mix).
-EXAMPLE I
To 47.2 grams of zinc sulfide, 0.9 grams of gold mix, 1.28 grams of aluminum mix and 0.64 grams of copper mix were added, corresponding to levels of these activators in parts per million of 27 gold, 64 copper, and 256 aluminum.
Two grams of a flux mix in the ratio of 90 parts by weight sulfur and 30 parts by weight potassium bromLde were added to the mixture andthe mixture was blended. It was then placed in a quartz tray and flred for about 2~ hours at about 1850F under a flowing CS2 atmosphere. The powder was then cooled and washed to remove soluble flux, followed ~y drying. The resulting sal-~le was formed into a packed bed and subjected to 14~V cathode rays and the color coordinates and brightness were measured vs. a standard zinc-~3Z79~
cadmium sulfide coactivated with copper and aluminum in the amoun~s of about 50 parts per million copper and 100 parts per million aluminum. The m~lar ratio of zinc to cadmium in the standard was 14.45:1. The standard had x and y coordinate values of 0.340 and 0.595 respectively and was assigned a brightness level of 100 percent. The sample pro-duced x and y coordinate values of 0.271 and 0.557 respect-ively and a brightness of 91 percent.
EXAMPLE II
The procedure of Example I was repeated except that 41.38 grams of zinc sulfide were mixed with 6.7 grams of gold mix, 1.28 grams of aluminum mix and 0.64 grams of copper mix, corresponding to levels of activators in parts per million of 200 gold, 64 copper and 256 aluminum. This sample yielded x and y coordinate values of 0.291 and 0.573 respectively - ` and a relative brightness of 85 percent of standard.
EXAMPLE III
The procedure of Example I was repeated except that 29.88 grams of zinc sulfide were mixed with 18.2 grams of gold mix, 1.28 grams of alumlnum mix and 0.64 grams of copper mix, corresponding to levels of these actlvators in parts per million of 546 gold, 64 copper and 256 aluminum. This sample yielded x and y coordinate values of 0.307 and 0.573 respectively and a brightness of 77 percent of~standard.
EXAMPLE IV
The procedure of Example I was repeated except that 21.75 grams of zinc sulflde were mixed with 25 grams of gold mix 1.75 grams of aluminum mix and 1.5 grams of copper mix, corresponding to levels of these activators in parts per million of 750 gold, 150 copper and 350 aluminum. The sample yielded x and y coordinate values of 0.299 and 0.5~6 respectively, and a relative brightness of 72 percent of standard.
~L3Z~
EXAMPLE V
The procedure of Example I was repeated except that25.5 gramsof zinc sulfide were mixed with 20 grams of gold mix, 3 grams of aluminum mix and 1.5 grams of copper mix, corres-ponding to levels of these act-vators in parts per million of 600 gold, 150 copper and 600 aluminum. This sample yielded x and y coordinate values of 0.325 and 0.582 respec-tively, and a relative brightness of 70 percent of standard.
EXAMPLE VI
The procedure of Example I was repeated except that 27.75 grams of zinc sulfide were mixed with 20 grams of gold mix, 1.75 grams of aluminum mix and 0.5 grams of copper mix, - corresponding to levels of these activators in parts per million of 600 gold, 50 copper and 350 aluminum. This sample yielded a phosphor with x and y coordinate values of 0.309--and 0.568 respectively in a relative brightness of 76 percent of standard.
The results of these six samples are tabulated below in Table I.
TABLE I
x y Brightness Std. ZnCdS:Al, Cu 340 .595 100 SAMPLE Cu Al Au (in parts per million) 1 64 256 27 .271 .557 91%
2 64 256 200 .291 .573 85 3 64 256 546 .307 .573 77~
4 150 350 750 .299 .586 ~72%
150 600 600 .325 .582 ~70 6 50 350 600 .309 .568 76 ~r ~13~79~
While there has been shown and described what are at present considered the preferred embodiments of the invention, it will be obvious to those skilled in the art that various changes and modifications may be therein without departing from the scope of the invention as defined by the appended claims.
rl
150 600 600 .325 .582 ~70 6 50 350 600 .309 .568 76 ~r ~13~79~
While there has been shown and described what are at present considered the preferred embodiments of the invention, it will be obvious to those skilled in the art that various changes and modifications may be therein without departing from the scope of the invention as defined by the appended claims.
rl
Claims
1. A zinc sulfide cathodoluminescent phosphor co-activated by gold, copper and aluminum, said gold, copper and aluminum being present in the ranges of about 350 to 550 parts per million, 50 to 150 and 300 to 600 parts per million respectively, and wherein the phosphor upon cathodoluminescent emission exhibits x and y coordinate values within the range of .320 to .345 and .570 to .580 respectively.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US86655678A | 1978-01-03 | 1978-01-03 | |
| US866,556 | 1978-01-03 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1132791A true CA1132791A (en) | 1982-10-05 |
Family
ID=25347865
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA317,236A Expired CA1132791A (en) | 1978-01-03 | 1978-12-01 | Zinc sulfide phosphor coactivated with gold, copper and aluminum |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JPS5497591A (en) |
| CA (1) | CA1132791A (en) |
| DE (1) | DE2856053A1 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0361650B1 (en) * | 1988-09-29 | 1994-06-15 | Samsung Display Devices Co., Ltd. | Green light emitting phosphor |
| JP2795893B2 (en) * | 1989-04-12 | 1998-09-10 | 株式会社東芝 | Cathode ray tube |
-
1978
- 1978-12-01 CA CA317,236A patent/CA1132791A/en not_active Expired
- 1978-12-23 DE DE19782856053 patent/DE2856053A1/en not_active Withdrawn
- 1978-12-28 JP JP16129278A patent/JPS5497591A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5497591A (en) | 1979-08-01 |
| DE2856053A1 (en) | 1979-07-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4208299A (en) | Method of preparing zinc sulfide phosphor coactivated with copper and gold | |
| EP0091184B1 (en) | Phosphors and their use in electron-excited fluorescent displays | |
| US4140940A (en) | Green emitting fluorescent composition and color television cathode ray tube using the same | |
| CA1132791A (en) | Zinc sulfide phosphor coactivated with gold, copper and aluminum | |
| US6090311A (en) | Alkali iodide doped zinc sulfide electroluminescent phoshor | |
| US2743239A (en) | Electroluminescent zinc sulfide phosphor and method of freparation | |
| JPS6254785A (en) | Sulfide phosphor | |
| US4925593A (en) | Method for producing cadmium free green emitting CRT phosphor | |
| US5232626A (en) | Process for making apatitic phosphors | |
| JPH0458518B2 (en) | ||
| EP0361650B1 (en) | Green light emitting phosphor | |
| EP0078538B1 (en) | Blue emitting phosphor exhibiting long afterglow and electron excited display device using the same | |
| CA2278991C (en) | Electroluminescent phosphor having purple emission | |
| KR920004166B1 (en) | Green luminous fluorescent substance | |
| US3052638A (en) | Preparation of recalcined zinc sulfide phosphors | |
| US3544478A (en) | Method for producing europium activated yttrium oxide phosphors | |
| KR910007796B1 (en) | Cathode ray tube | |
| JPH072946B2 (en) | Fluorescent body | |
| KR100286934B1 (en) | Green luminescent phosphor | |
| KR960000869B1 (en) | Fluorescent material and its preparation method of the same | |
| PL120590B1 (en) | Method of manufacture of luminophores comprising mainly zinc sulfide activated with aluminium,copper and goldazom iz sul'fida cinka,aktivirovannogo aljuminiem,med'ju i zolotom | |
| JPH0129834B2 (en) | ||
| KR920005957B1 (en) | Green luminous fluorescent substance | |
| SU924075A1 (en) | Method for producing phosphors based on zink or zink and cadmium sulphides | |
| US2732347A (en) | Luminescent zinc |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |