US4551397A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Zinc silicate phosphor and electron excited fluorescent display device using the phosphor
Assignee: Mitsubishi Chemical Corp
•
Filing: 1984-04-03
•
Granted: 1985-11-05
•
Expires: 2004-04-03
Abstract
Abstract A zinc silicate phosphor represented by the formula: (Zn.sub.1-x-2y, M.sup.II.sub.x, Na.sub.2y).sub.2 SiO.sub.4 :Mn.sub.a, As b , M c (I) where M II is at least one element selected from the group consisting of barium, calcium and strontium, M is at least one of antimony and bismuth, and x, y, a, b and c satisfy the conditions of O≦x≦5×10 -2 , O≦2y≦5×10 -3 , 5×10 -5 ≦a≦3×10 -2 , O≦b≦5×10 -3 and O<c≦1×10 -2 , respectively (provided x+2y≠0).
Inventors
- 👤 Masachika Yaguchi
- 👤 Tomoki Mikami
- 👤 Takashi Hase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 03:36
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/64; C09K11/641; C09K11/642; C09K11/61; C09K11/611; C09K11/612; C09K11/62; C09K11/626; C09K11/644; C09K11/70; C09K11/701; C09K11/703; C09K11/71; C09K11/74; C09K11/7442; C09K11/7464; C09K11/7471; C09K11/75; C09K11/757; H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/18; H01J29/30; H01J29/32
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
97 words
A zinc silicate phosphor represented by the formula: (Zn.sub.1-x-2y, M.sup.II.sub.x, Na.sub.2y).sub.2 SiO.sub.4 :Mn.sub.a, As.sub.b, M.sub.c (I) where M II is at least one element selected from the group consisting of barium, calcium and strontium, M is at least one of antimony and bismuth, and x, y, a, b and c satisfy the conditions of 0≦×≦5×10 -2 , 0≦2y≦5×10 -3 , 5×10 -5 ≦a≦3×10 -2 , 0≦b≦5×10 -3 and 0<c≦1×10 -2 , respectively, provided x+2y≠0, and exhibiting a higher fluorescence maintaining rate than said phosphor where c=0, and a higher fluorescence maintaining rate than said phosphor where x+2y=0.
Claim 2
Dependent Claim
97 words
A zinc silicate phosphor represented by the formula: (Zn.sub.1-x-2y, M.sup.II.sub.x, Na.sub.2y).sub.2 SiO.sub.4 :Mn.sub.a, As.sub.b, M.sub.c (I) where M II is at least one element selected from the group consisting of barium, calcium and strontium, M is at least one of antimony and bismuth, and x, y, a, b and c satisfy the conditions of 0≦×≦5×10 -2 , 0≦2y≦5×10 -3 , 5×10 -5 ≦a≦3×10 -2 , 0≦b≦5×10 -3 and 0<c≦1×10 -2 , respectively, provided x+2y≠0, and exhibiting a higher fluorescence maintaining rate than said phosphor where c=0, and a higher fluorescence maintaining rate than said phosphor where x+2y=0.
Claim 3
Dependent Claim
11 words
The zinc silicate according to claim 1, wherein M is antimony.
Claim 4
Dependent Claim
13 words
The zinc silicate phosphor according to claim 2, wherein M II is barium.
Claim 5
Dependent Claim
13 words
The zinc silicate phosphor according to claim 2, wherein M II is barium.
Claim 6
Dependent Claim
26 words
The zinc silicate phosphor according to claim 1, wherein b and c satisfy the conditions of 1×10 -5 ≦b≦2×10 -3 and 1×10 -5 ≦c≦5×10 -3 .
Claim 7
Dependent Claim
19 words
The zinc silicate phosphor according to claim 1, wherein the value of 2y is 1×10 -5 ≦2y≦2×10 -3 .
Claim 8
Dependent Claim
119 words
An electron excited fluorescent display device having a fluorescent screen, wherein a zinc silicate phosphor represented by the formula: (Zn.sub.1-x-2y, M.sup.II.sub.x, Na.sub.2y).sub.2 SiO.sub.4 :Mn.sub.a, As.sub.b, M.sub.c (I) where M II is at least one element selected from the group consisting of barium, calcium and strontium, M is at least one of antimony and bismuth, and x, y, a, b and c satisfy the conditions of 0≦x≦5×10 -2 , 0≦2y≦5×10 -3 , 5×10 -5 ≦a≦3×10 -2 , 0≦b≦5×10 -3 and 0<c≦1×10 -2 , respectively, provided x+2y≠0, and exhibiting a higher fluorescence maintaining rate than said phosphor where c=0 and a higher fluorescence maintaining rate than said phosphor where x+2y=0, is used as a green emitting component of the fluorescent screen.
Claim 9
Dependent Claim
119 words
An electron excited fluorescent display device having a fluorescent screen, wherein a zinc silicate phosphor represented by the formula: (Zn.sub.1-x-2y, M.sup.II.sub.x, Na.sub.2y).sub.2 SiO.sub.4 :Mn.sub.a, As.sub.b, M.sub.c (I) where M II is at least one element selected from the group consisting of barium, calcium and strontium, M is at least one of antimony and bismuth, and x, y, a, b and c satisfy the conditions of 0≦x≦5×10 -2 , 0≦2y≦5×10 -3 , 5×10 -5 ≦a≦3×10 -2 , 0≦b≦5×10 -3 and 0<c≦1×10 -2 , respectively, provided x+2y≠0, and exhibiting a higher fluorescence maintaining rate than said phosphor where c=0 and a higher fluorescence maintaining rate than said phosphor where x+2y=0, is used as a green emitting component of the fluorescent screen.
Claim 10
Dependent Claim
123 words
The electron excited fluorescent display device according to claim 7, wherein the fluorescent screen comprises green, red and blue emitting phosphors having long after-glow characteristics, in which: (I) the green emitting phosphor is composed essentially of a zinc silicate phosphor represented by the formula I and has a 10% after-glow period of from 5 to 150 milliseconds; (II) the red emitting phosphor is composed essentially of a long after-glow red to orange emitting phosphor with a 10% after-glow period of at least 5 milliseconds and having a 10% after-glow period of from 5 to 150 milliseconds; and (III) the blue emitting phosphor is composed of a blue to bluish white emitting phosphor having a 10% after-glow period of from 5 to 150 milliseconds.
Claim 11
Dependent Claim
84 words
The electron excited fluorescent display device according to claim 8, wherein the red emitting phosphor is composed essentially of a phosphate phosphor represented by the formula: (Zn.sub.1-z, Mg.sub.z).sub.3 (PO.sub.4).sub.2 :Mn.sub.i, M.sub.j, M'.sub.k (II) where M is at least one element selected from the group consisting of calcium, strontium, barium, beryllium, zirconium and tin, M' is at least one of arsenic and lead, and i, j, k and z satisfy the conditions of 5×10 -4 ≦i≦10 -1 , 0≦j≦10 -1 , 0≦k≦10 -1 and 0≦z<1.
Claim 12
Dependent Claim
91 words
The electron excited fluorescent display device according to claim 8, wherein the blue emitting phosphor is composed essentially of a long after-glow blue to bluish white emitting sulfide phosphor represented by the formula: ZnS:Ag, M.sub.m, M', X (III) where M is at least one of copper and gold, M' is at least one element selected from the group consisting of gallium, indium and scandium, X is at least one element selected from the group consisting of fluorine, chlorine, bromine, iodine and aluminum, and m is a positive numerical value including zero.
Claim 13
Dependent Claim
14 words
The electron excited fluorescent display device according to claim 7, wherein M is antimony.
Claim 14
Dependent Claim
15 words
The electron excited fluorescent display device according to claim 11, wherein M II is barium.
Claim 15
Dependent Claim
15 words
The electron excited fluorescent display device according to claim 11, wherein M II is calcium.
Claim 16
Dependent Claim
29 words
The electron excited fluorescent display device according to claim 7, wherein b and c satisfy the conditions of 1×10 -5 ≦b≦2×10 -3 and 1×10 -5 ≦c≦5×10 -3 , respectively.
Claim 17
Dependent Claim
21 words
The electron excited fluorescent display device according to claim 7, wherein the value of 2y is 1×10 -5 ≦2y≦2×10 -3 .
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-11-04 | 1989-05-06 | 1989-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-11-04 | 1993-05-06 | 1993-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-11-04 | 1997-05-06 | 1997-11-05 | $7700.00 | Window Closed / Lapsed |