US4407916A
Expired / Lapsed
US
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Process for forming fluorescent screen
Assignee: Hitachi Ltd
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Filing: 1982-03-15
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Granted: 1983-10-04
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Expires: 2002-03-15
Abstract
Abstract A process for forming a fluorescent screen, where polychroic patterns are successively formed from at least two kinds of phosphors having different color emission or black powder by means of a photosensitive substance capable of turning tacky by light irradiation, which comprises bringing a finer particulate filling material than particles of the phosphors in contact with tackified parts when or after the particles of the phosphors are applied to the tackified parts in the individual steps of forming patterns each of the individual phosphors. The filling material saturates the tackiness of the phosphor pattern in question in advance to formation of a phosphor pattern in the successive step, and a cause for contamination of the pattern of the preceding step with the phosphor of the successive step can be eliminated thereby.
Inventors
- 👤 Motoo Akagi
- 👤 Shoichi Uchino
- 👤 Saburo Nonogaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:58
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/18; H01J29/22; H01J29/225; H01J9/00; H01J9/20; H01J9/22; H01J9/227; H01J9/2271
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
232 words
A process for forming a fluorescent screen, where patterns each of individual phosphors are formed in zones discrete from one phosphor to another on a substrate surface from at least two kinds of phosphors, which comprises (1) a first step of applying a thin layer of a photosensitive substance capable of turning tacky by light exposure, (2) a second step of exposing the thin layer to light irradiation according to a pattern of one kind of the phosphors, thereby tackifying the light-exposed parts, and (3) a third step of applying particles of the said one kind of the phosphors, and a finer particulate filling material than the particles of the phosphor, to the tackified parts of the thin layer after the light exposure, said finer particulate filling material being at least one material selected from the group consisting of: (i) metal phosphates; (ii) SiO 2 ; (iii) MgCO 3 ; (iv) powders of organic polymer having a heat decomposition point of less than 450° C.; and (v) much finer particles of phosphor having substantially the same color emission as that of the phosphor in the phosphor layer to be treated with the finer particulate filling material, thereby forming the pattern of the said one kind of the phosphors having the finer particulate filling material filling in clearances between the phosphor particles and between the phosphor particles and peripheries of the tackified parts.
Claim 2
Dependent Claim
232 words
A process for forming a fluorescent screen, where patterns each of individual phosphors are formed in zones discrete from one phosphor to another on a substrate surface from at least two kinds of phosphors, which comprises (1) a first step of applying a thin layer of a photosensitive substance capable of turning tacky by light exposure, (2) a second step of exposing the thin layer to light irradiation according to a pattern of one kind of the phosphors, thereby tackifying the light-exposed parts, and (3) a third step of applying particles of the said one kind of the phosphors, and a finer particulate filling material than the particles of the phosphor, to the tackified parts of the thin layer after the light exposure, said finer particulate filling material being at least one material selected from the group consisting of: (i) metal phosphates; (ii) SiO 2 ; (iii) MgCO 3 ; (iv) powders of organic polymer having a heat decomposition point of less than 450° C.; and (v) much finer particles of phosphor having substantially the same color emission as that of the phosphor in the phosphor layer to be treated with the finer particulate filling material, thereby forming the pattern of the said one kind of the phosphors having the finer particulate filling material filling in clearances between the phosphor particles and between the phosphor particles and peripheries of the tackified parts.
Claim 3
Dependent Claim
38 words
The process according to claim 1, wherein the third step is carried out by applying the particles of the said one kind of the phosphors at first, and then the finer particulate filling material to the tackified parts.
Claim 4
Dependent Claim
38 words
The process according to claim 1, wherein the third step is carried out by applying a mixture of the particles of the said one kind of the phosphors and the finer particulate filling material to the tackified parts.
Claim 5
Dependent Claim
51 words
The process according to claim 1, wherein the third step is carried out by applying the particles of the said one kind of phosphors at first, and then a mixture of the particles of the said one kind of the phosphors and the finer particulate filling material to the tackified parts.
Claim 6
Dependent Claim
36 words
The process according to any one of claims 1 to 4, wherein the finer particulate filling material is at least one compound selected from the group consisting of metal phosphates, SiO 2 and MgCO 3 .
Claim 7
Dependent Claim
124 words
The process according to any one of claims 1 to 4, wherein the finer particulate filling material is at least one of said metal phosphates, and the at least one metal phosphate is selected from the group consisting of M 3 (PO 4 ) 2 , wherein M is at least one element selected from the group consisting of Mg, Ca, Sr, Ba and Zn, M'PO 4 , wherein M' is at least one element selected from the group consisting of La, Ce, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Al, Ga, In, Sc and Y, Al(PO 3 ) 3 and M"(PO 3 ) 2 , where M" is at least one element selected from the group consisting of Ca and Sn.
Claim 8
Dependent Claim
32 words
The process according to any one of claims 1 to 4, wherein the finer particulate filing material is powders of organic polymer having a heat decomposition point of less than 450° C.
Claim 9
Dependent Claim
41 words
The process according to claim 7, wherein the organic polymer is at least one member selected from the group consisting of alginic acid, alginate, methylcellulose, hydroxypropylmethylcellulose, vinylmethylether-maleic acid anhydride copolymer, polystyrene, poly-α-methylstyrene, polymethyl acrylate, polymethyl methacrylate, polyvinylidene chloride, and polyvinyl acetate.
Claim 10
Dependent Claim
47 words
The process according to any one of claims 1 to 4, wherein the finer particulate filling material is much finer particles of phosphor having substantially the same color emission as that of the phosphor in the phosphor layer to be treated with the finer particulate filling material.
Claim 11
Dependent Claim
25 words
The process according to any one of claims 1 to 4, wherein the finer particulate filling material has an average particle size of 0.1-3 μm.
Claim 12
Dependent Claim
24 words
The process according to any one of claims 1 to 4, wherein the photosensitive substance contains an aromatic diazonium salt as a photosensitive component.
Claim 13
Dependent Claim
30 words
The process according to any one of claims 1 to 4, wherein the surface of the substrate is an inside surface of a face plate of a cathode ray tube.
Claim 14
Dependent Claim
20 words
The process according to claim 10, wherein the finer particulate filling material has an average particle size of 0.1-1 μm.
Claim 15
Dependent Claim
19 words
The process according to claim 13, wherein the average particle size of the particles of phosphor is 5-15 μm.
Claim 16
Dependent Claim
23 words
The process according to claim 3, wherein said mixture contains 5-30% by weight of the filling material on the basis of the phosphor.
Claim 17
Dependent Claim
23 words
The process according to claim 4, wherein said mixture contains 10-60% by weight of the filling material on the basis of the phosphor.
Claim 18
Dependent Claim
75 words
The process according to claim 1, further comprising the steps of exposing the thin layer to a second light irradiation, according to a pattern of a second kind of the phosphors, thereby tackifying the light-exposed parts, and then applying particles of said second kind of phosphor, and said finer particulate filling material than the particles of the second kind of phosphor, to the parts of the thin layer made tacky by the second light irradiation.
Claim 19
Dependent Claim
75 words
The process according to claim 17, further comprising the steps of exposing the thin layer to a third light irradiation, according to a pattern of a third kind of the phosphors, thereby tackifying the light-exposed parts, and then applying particles of said third kind of phosphor, and said finer particulate filling material than the particles of the third kind of phosphor, to the parts of the thin layer made tacky by the third light irradiation.
Claim 20
Dependent Claim
20 words
The process according to claim 18, wherein the three kinds of phosphors are blue-emitting phosphors, green-emitting phosphors, and red-emitting phosphors.
Claim 21
Dependent Claim
35 words
The process according to claim 1, wherein said finer particulate filling material fills in the clearances between said particles of the phosphor and between particles of the phosphor and the peripheries of the tackified parts.
Claim 22
Dependent Claim
216 words
A process for forming a fluorescent screen, where patterns each of individual phosphors are formed in zones discrete from one phosphor to another on a substrate surface from at least two kinds of phosphors, which comprises (1) a first step of applying a thin layer of a photosensitive substance capable of turning tacky by light exposure, (2) a second step of exposing the thin layer to light irradiation according to a pattern of one kind of the phosphors, thereby tackifying the light-exposed parts, and (3) a third step of applying particles having an average particle size of 5-15 μm of the said one kind of the phosphors, and a finer particulate filling material than the particles of the phosphor, which filling material has an average particle size of 0.1-3 μm and has no absorption band in the visible range, to the tackified parts of the thin layer after the light exposure, said finer particulate filling material filling in the clearances between said particles of the phosphor and between particles of the phosphor and the peripheries of the tackified parts, whereby the pattern of the said one kind of the phosphors having the finer particulate filling material filling in clearances between the phosphor particles and between the phosphor particles and peripheries of the tackified parts is formed.
Claim 23
Dependent Claim
216 words
A process for forming a fluorescent screen, where patterns each of individual phosphors are formed in zones discrete from one phosphor to another on a substrate surface from at least two kinds of phosphors, which comprises (1) a first step of applying a thin layer of a photosensitive substance capable of turning tacky by light exposure, (2) a second step of exposing the thin layer to light irradiation according to a pattern of one kind of the phosphors, thereby tackifying the light-exposed parts, and (3) a third step of applying particles having an average particle size of 5-15 μm of the said one kind of the phosphors, and a finer particulate filling material than the particles of the phosphor, which filling material has an average particle size of 0.1-3 μm and has no absorption band in the visible range, to the tackified parts of the thin layer after the light exposure, said finer particulate filling material filling in the clearances between said particles of the phosphor and between particles of the phosphor and the peripheries of the tackified parts, whereby the pattern of the said one kind of the phosphors having the finer particulate filling material filling in clearances between the phosphor particles and between the phosphor particles and peripheries of the tackified parts is formed.
Claim 24
Dependent Claim
20 words
The process according to claim 21, wherein the finer particulate filling material has an average particle size of 0.1-1 μm.
Claim 25
Dependent Claim
25 words
The process according to claim 21 or 22 wherein the photosensitive substance is a photosensitive material containing an aromatic diazonium salt as a photosensitive component.
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) | 1986-10-03 | 1987-04-04 | 1987-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-03 | 1991-04-04 | 1991-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-03 | 1995-04-04 | 1995-10-04 | $7700.00 | Window Closed / Lapsed |