Claims
- 1. A method for making a high energy beam-sensitive (HEBS) glass article, said glass article comprising an integral ion-exchanged surface layer (IIES layer) having Ag+ ions therein, and/or silver halide-containing and/or Ag.sub.2 O-containing and/or Ag+ ion-containing microcrystals and/or microphases therein, containing silanol groups and/or water having a concentration of more than about 0.01% by weight H.sub.2 O, which comprises the steps:
- (a) contacting the surface of a parent glass article with a Ag+ ion-containing material and/or an aqueous solution containing Ag+ ions, the parent glass article being prepared from a glass batch melt and having glass composition comprising at least one alkali metal oxide selected from the group consisting of Li.sub.2 O, Na.sub.2 O, K.sub.2 O, Cs.sub.2 O and Rb.sub.2 O, at least one photosensitivity-inhibitor (PI agent) and/or red-shift suppression agent (RS-Suppression agent or RSS agent), SiO.sub.2, and from zero up to saturation of halide in the glass melt, the glass composition containing an effective amount of photosensitivity inhibitors to render the IIES layer substantially photoinsensitive to substantially all actinic radiation having a wavelength longer than 400 nm,
- (b) heating said parent glass article together with said Ag+ ion-containing material and/or said aqueous solution containing Ag+ ions in contact therewith to a temperature sufficient to effect an exchange of Ag+ ions for said alkali metal ions in at least the surface of said parent glass article for a period of time sufficient to allow the ion exchange reactions to proceed in thickness dimension into the surface of said parent glass article to form the IIES layer.
- 2. A method of claim 1 wherein said silver ions exchange with alkali metal ions in said glass composition, whereby the concentration of alkali metal ions in the resultant IIES layer is lower than that of the parent glass article.
- 3. A method of claim 1 wherein the surface of said IIES layer which is ion exchanged has substantially the same surface quality and surface figure after the ion exchange treatment as before said treatment.
- 4. A method of claim 1 wherein said ion exchange reactions cause the formation of said silver halide-containing and/or said Ag.sub.2 O-containing and/or said Ag+ ion-containing microcrystals and/or microphases within the IIES layer.
- 5. A method of claim 1 wherein said photosensitivity inhibitor and/or RS-suppression agent is an amount of at least 0.5% total of oxides of transition metals which have 1 to 4 d-electrons in the atomic state, effective to render said IIES layer substantially photoinsensitive to substantially all actinic radiation having a wavelength longer than 400 nm and photosensitive to radiation of energy higher than that of a wavelength of 400 nm.
- 6. A method of claim 5 wherein the amount of photosensitivity inhibitors is effective to render said IIES layer substantially photoinsensitive to substantially all actinic radiation having a wavelength longer than 200 nm and photosensitive to radiation of energy higher than that of a wavelength of 200 nm.
- 7. A method of claim 5 wherein the amount of photosensitivity inhibitors is effective to render said IIES layer substantially photoinsensitive to substantially all actinic radiation having a wavelength longer than 300 nm and photosensitive to radiation of energy higher than that of a wavelength of 300 nm.
- 8. A method of claim 7 wherein the IIES layer is sensitive to high energy beam which is a high voltage electron beam, an ion beam, at atomic beam, a molecular beam, x-ray radiation or deep uv radiation having wavelengths shorter than 300 nm.
- 9. A method according to claim 8 wherein at least a portion of said IIES is darkened with said high energy beam.
- 10. A method according to claim 9 wherein recorded image is formed in the darkened IIES layer by bit-by-bit heat-erasure in a predetermined pattern using a high intensity light beam including laser beams, at whose wavelengths there is absorption of light within the darkened IIES layer.
- 11. A method according to claim 10 wherein the glass article is a read-only optical disc and/or a write-once-read-many (WORM) disc.
- 12. A method according to claim 10 wherein the glass article is a write-erasable optical disc, said write-erase is done using a uv laser beam modulated between two power levels.
- 13. A method according to claim 10 wherein an etched surface relief pattern corresponding to the recorded image is formed through a selective etching means which includes etching the surface of the IIES layer bearing the recorded image by wet chemical etching or plasma etching.
- 14. A method according to claim 8 wherein the IIES layer is exposed to said high energy beam in a predetermined pattern to produce recorded image.
- 15. A method according to claim 14 wherein at least a portion of the recorded image is erased by heat including bit by bit erasure and flood erasure, using a heat source including oven, hot plate and high intensity light beams which include laser beams.
- 16. A method according to claim 14 wherein an etched surface relief pattern corresponding to the recorded image is formed through a selective etching means which includes etching the surface of the IIES layer bearing the recorded image by wet chemical etching or plasma etching.
- 17. A method of claim 8 wherein a coloration induced by exposure to said high energy beams being selected from yellow, reddish orange, reddish brown, brown, red, reddish magenta, reddish black, magenta, bluish magenta, blue, violet gray, blue gray, bluish black, gray and black.
- 18. A method of claim 17 wherein said coloration is obtained through the choice of base glass composition, ingredients and acidity of the aqueous ion exchange solution, and/or reaction temperature and duration.
- 19. A method of claim 18 wherein a variety of colorations and/or hues are obtained within a single piece of the glass article using energy of the high energy beam and/or exposure dosage of the high energy beam as variable parameters.
- 20. A method of claim 17 wherein a variety of E-beam induced colorations selected from said colorations are obtained within a variety of HEBS glass articles which are prepared from a single base glass composition.
- 21. A method of claim 8 wherein spectral band shapes, including the wavelengths of the absorption peaks and the band widths of the absorption spectra induced by exposure to said high energy beam, are designed for specific applications through the choice of base glass composition, ingredients and acidity of the aqueous ion-exchange solution, temperature and duration of ion exchange reactions, energy of high energy beam, and/or exposure dosage of the high energy beam.
- 22. A method of claim 5 wherein said amount is effective to render said IIES layer substantially photoinsensitive to substantially all actinic radiation having a wavelength longer than 365 nm and photosensitive to radiation of energy higher than that of a wavelength of 365 nm.
- 23. A method of claim 5 wherein said photosensitivity inhibitor and/or RS-suppression agent is an amount of less than 35% total of oxides of transition metals which have 1 to 4 d-electrons in the atomic state, effective to render said IIES layer substantially photoinsensitive to substantially all actinic radiation having a wavelength longer than 400 nm and photosensitive to radiation of photon-energy higher than that of a wavelength of 400 nm.
- 24. A method of claim 23 wherein said amount is effective to render said IIES layer substantially photoinsensitive to substantially all actinic radiation having a wavelength longer than 436 nm and photosensitive to radiation of energy higher than that of a wavelength of 436 nm.
- 25. A method according to claim 1 wherein said photosensitivity inhibitor and/or RS-suppression agent is at least one oxide of a transition metal selected from the group consisting of TiO.sub.2, Ta.sub.2 O.sub.5, ZrO.sub.2, Nb.sub.2 O.sub.5, La.sub.2 O.sub.3, Y.sub.2 O.sub.3 and WO.sub.3.
- 26. A method according to claim 1 wherein said photosensitivity inhibitor is at least one oxide of a transition metal selected from the group consisting of TiO.sub.2, Ta.sub.2 O.sub.5, Y.sub.2 O.sub.3 and Nb.sub.2 O.sub.5.
- 27. A method according to claim 1 wherein said photosensitivity inhibitor is at least one oxide of a transition metal selected from the group consisting of TiO.sub.2, Y.sub.2 O.sub.3 and Nb.sub.2 O.sub.5.
- 28. A method of claim 1 wherein said photosensitivity inhibitor and/or RS-suppression agent includes, in mole %, at least 0.5% TiO.sub.2.
- 29. A method according to claim 1 wherein said glass composition containing in mole percent, at least 1.5% TiO.sub.2.
- 30. A method according to claim 1 wherein said glass composition containing in mole percent on the oxide basis at least 2% total of at least one acid-durability-and-glass-network-strengthener selected from the group consisting of ZnO, PbO, MgO, CaO and Al.sub.2 O.sub.3.
- 31. A method according to claim 1 wherein said glass composition containing, in mole percent, 2% to 20% ZnO, 0 to 10% Al.sub.2 O.sub.3, and 1.2% to 25% TiO.sub.2.
- 32. A method according to claim 1 wherein said glass composition contains 10-20%, mole percent, total of Li.sub.2 O, Na.sub.2 O, and K.sub.2 O, and in the glass batch 0.8-6%, mole percent, Cl.
- 33. A method according to claim 1 wherein said glass composition contains in mole percent, up to 3% Cl, in the glass batch.
- 34. A method according to claim 1 wherein said glass composition contains in mole percent 3-10% TiO.sub.2 and 60-82% SiO.sub.2.
- 35. A method according to claim 1 wherein said glass composition contains in mole percent, up to 7.2% B.sub.2 O.sub.3.
- 36. A method according to claim 1 wherein said glass composition contains in mole percent 0.5-5% Al.sub.2 O.sub.3.
- 37. A method according to claim 1 wherein said glass composition contains in mole percent up to 20% PbO.
- 38. A method of claim 1 wherein said glass composition consisting essentially of, in mole percent on the oxide basis,
- 5-25% of one or more alkali metal oxides,
- up to 6% Cl
- 0. 5-35% total concentration of photosensitivity inhibitors and RS-suppression agents,
- 2% to 20% ZnO,
- up to 20% MgO,
- up to 15% Al.sub.2 O.sub.3,
- up to 20% PbO,
- up to 20% CaO,
- 2-35% total of at least one acid-durability-and glass-network-strengthener selected from the group consisting of MgO, ZnO, Al.sub.2 O.sub.3, PbO, and CaO,
- up to 20% BaO,
- up to 25% B.sub.2 O.sub.3,
- up to 25% P.sub.2 O.sub.5,
- up to 4% F,
- up to 2% Br,
- up to 2% I, and
- 50-89% SiO.sub.2.
- 39. A method according to claim 1 wherein said glass composition consisting essentially of, in mole percent on the oxide basis,
- 12-16% total of Li.sub.2 O, Na.sub.2 O, and K.sub.2 O,
- 3-10% total of oxides of transition metals having 1 to 4 d-electrons in the atomic state, including 3-10% TiO.sub.2, the glass composition containing a sufficient amount of the oxides of transition metals having 1 to 4 d-electrons in the atomic state to render the IIES layer substantially photoinsensitive to substantially all actinic radiation having a wavelength longer than 400 nm,
- 4-10% ZnO,
- 0.5-5% Al.sub.2 O.sub.3,
- 0.8-6% Cl, and
- 68-75% SiO.sub.2.
- 40. A method according to claim 1 wherein said glass composition consisting essentially of, in mole percent on the oxide basis,
- 10-20% total of Li.sub.2 O, Na.sub.2 O, K.sub.2 O, Rb.sub.2 O, and Cs.sub.2 O,
- 0.5-8.4% total of photosensitivity inhibitors (PI agents) and RS-suppression agents (RSS agents), the glass composition containing at least an effective amount of PI agents to render said IIES layer substantially photoinsensitive to substantially all actinic radiation having a wavelength longer than 400 nm, including 0.5 to 7.4% TiO.sub.2,
- 3.6-7.6% ZnO,
- 0. 6-2.4% Al.sub.2 O.sub.3,
- up to 10.8% MgO,
- up to 4% CaO,
- up to 4% BaO,
- up to 3.5% PbO,
- up to 4% SrO,
- up to 7.2% B.sub.2 O.sub.3,
- up to 7.2% P.sub.2 O.sub.5,
- up to 1.5% halide selected from the group consisting of F, Br, and I,
- 0.8-6% Cl, and
- 58.5-73.2% SiO.sub.2.
- 41. A method according to claim 1 wherein said glass composition consisting essentially of, in mole percent on the oxide basis,
- 3-25% total of one or more alkali metal oxide,
- 1.5-35% total concentration of photosensitivity inhibitors (PI agents) and RS-suppression agents selected from the group consisting of TiO.sub.2, Nb.sub.2 O.sub.5, Y.sub.2 O.sub.3 and Ta.sub.2 O.sub.5,
- up to 35% of acid-durability-and-glass-network-strengtheners (ADAGNS),
- up to 25% P.sub.2 O.sub.5,
- up to 25% B.sub.2 O.sub.3,
- up to 4% F,
- up to 6% Cl,
- up to 2% Br,
- up to 2% I, and
- 2- 93% SiO.sub.2,
- the sum amount of the above components constituting at least 75 mole percent of the glass composition.
- 42. A method of claim 1 wherein the content of the silanol groups and/or water in said IIES layer is between 0.01% and 12% by weight H.sub.2 O.
- 43. A method of claim 1 wherein the content of the silanol groups and/or water in said IIES layer is between 0.1 and 6% by weight H.sub.2 O.
- 44. A method of claim 1 wherein said IIES layer contains in mole percent, 0.1-25% Ag.sub.2 O.
- 45. A method according to claim 1 wherein said glass composition contains in mole percent, up to 10.8% MgO.
- 46. A method according to claim 1 wherein the glass article is a phototool which is employed for the production of semiconductor chip products, pre-recorded optical discs, flat panel displays, hybrid circuits or printed circuit boards, by methods which employ photomasks and/or reticles in a photolithographic process.
- 47. A method of claim 1 wherein the glass article is an optical software disk employed to load programs into various computers as well as to supply a recording medium to serve the market for personal computers, video games, office systems, data distribution systems and other information systems, said optical software disk includes read-only discs, write-once-read-many discs and write-erasable discs.
- 48. A method according to claim 1 wherein the glass article is a write-erasable optical disc, said write-erase is done using a uv laser beam modulated between two power levels.
- 49. A method of claim 1 wherein the sensitivity of the IIES layer to high energy beams is increased through the choice of base glass composition, ingredients and acidity of the aqueous ion-exchange solution, and/or reaction temperature and duration.
- 50. A method of claim 49 wherein the sensitivity to electron beams increases with increasing chloride concentration in the glass composition.
- 51. A method of claim 49 wherein the sensitivity to electron beams increases with increasing concentration of silver ions in the IIES layer.
- 52. A method of claim 51 wherein the concentration of silver ions in the IIES layer increases with reducing acidity of the aqueous ion exchange solution.
- 53. A method of claim 51 wherein the concentration of silver ions in the IIES layer increases with increasing temperature of the ion exchange reactions.
- 54. A method of claim 51 wherein the concentration of silver ions in the IIES layer increases with increasing concentration of silver ions in the acidic aqueous ion exchange solution.
- 55. A method of claim 49 wherein a saturation optical density per unit thickness of the IIES layer increases with increasing E-beam sensitivity.
- 56. A method of claim 55 wherein a saturation optical density in the IIES layer is more than 0.1 for at least one wavelength.
- 57. A method of claim 55 wherein a saturation optical density in the IIES layer is more than 3 for at least one wavelength.
- 58. A method of claim 57 wherein the thickness of the IIES layer is less than 10 micrometers.
- 59. A method of claim 1 wherein said aqueous solution also contains acids and/or oxidizing agents.
- 60. A method of claim 1 wherein said aqueous solution also contains cuprous ions, cupric ions or mixtures thereof.
- 61. A method of claim 1 wherein said aqueous solution contains silver ions ranging from 10.sup.-4 mole/liter up to the concentration of a saturated AgNO.sub.3 solution, and H+ ions ranging from 10.sup.-6 mole/liter to 5 mole/liter.
- 62. A method of claim 1 wherein the aqueous solution contains HNO.sub.3 in the concentration range of 0.05 to 1.5 mole of HNO.sub.3 per liter of the aqueous solution.
- 63. A method of claim 1 wherein said aqueous solution contains HNO.sub.3 ranging from 3 cc up to 15 N HNO.sub.3, per liter of the aqueous solution.
- 64. A method of claim 1 wherein said aqueous solution contains silver ions ranging from 100 grams of AgNO.sub.3 per liter of the aqueous solution up to the concentration of a saturated AgNO.sub.3 solution.
- 65. A method of claim 1 wherein said aqueous solution contains 200 g AgNO.sub.3 per liter of the aqueous solution, and 10 to 200 cc of 16N HNO.sub.3 per liter of the aqueous solution.
- 66. A method of claim 1 wherein said aqueous solution contains 20 g AgNO.sub.3 per liter of the aqueous solution, and has a pH of between 1 and 6.
- 67. A method of claim 66 wherein the pH of said aqueous solution is kept at a value of more than 2, and said aqueous solution has a silver ion to hydrogen ion mole ratio of more than 5.
- 68. A method of claim 1 wherein said aqueous solution is a solution sufficiently buffered to maintain the solution's pH value throughout the ion exchange reaction.
- 69. A method of claim 1 wherein said aqueous solution has a mole ratio of silver ion to hydrogen ion, ranging from 5 to more than 50.
- 70. A method of claim 1 wherein the silver ion concentration of the aqueous solution is from 0.1 moles per liter up to the concentration of a saturated AgNO.sub.3 solution.
- 71. A method of claim 1 wherein said aqueous solution contains alkali metal ions up to saturated concentrations of one or more alkali metal ion containing salts.
- 72. A method of claim 1 wherein said aqueous solution also contains up to saturation of dissolved SiO.sub.2 and/or silica gel and/or water soluble silicates, and/or glass powder of HEBS glasses, and/or one or more constituent cations of said glass composition.
- 73. A method of claim 1 wherein said ion-exchange reactions include hydration and/or an exchange of H+ and/or H.sub.3 O+ ions for alkali metal ions in the surface of the glass article to produce the IIES layer containing silanol groups and/or water of more than 0.01% by weight H.sub.2 O.
- 74. A method of claim 1 wherein the glass article is treated at ion exchange temperatures of 350.degree. C. below the strain point of said glass composition up to the annealing point of said glass composition.
- 75. A method of claim 1 wherein the ion exchange reactions are at temperatures from 240.degree. C. to exceeding 360.degree. C.
- 76. A method of claim 75 wherein the glass article is treated at said reaction temperatures for a period of time between 1 minute and 8 hours.
- 77. A method of claim 1 wherein the ion exchange reactions are at temperatures between 300.degree. C. and the annealing point of said glass composition.
- 78. A method of claim 1 wherein the glass article is ion exchanged at reaction temperatures above 300.degree. C. for a duration of time between 1 minute and two hours.
- 79. A method of claim 1 wherein said ion exchange reactions are carried out at pressures at least equal to the saturated vapor pressures of said aqueous solution.
- 80. A method of claim 79 wherein the pressure is maintained at values above the saturated vapor pressure of said aqueous solution.
- 81. A method of claim 80 wherein the vapor phase above the aqueous solution contains nitrogen, air, oxygen, and/or argon.
- 82. A method of claim 1 wherein the parent glass article is formed and shaped from the glass batch melt as a glass sheet with at least a portion of the glass sheet's surface ground and polished.
- 83. A method of claim 1 wherein the surface of the glass article is doped and/or enriched with chloride/chlorine prior to and/or after the ion exchange treatment.
- 84. A method of claim 1 wherein the glass batch melt is melted in an oxidizing atmosphere.
- 85. A method according to claim 1 wherein the melting is done in an atmosphere having a partial pressure of chlorine or chlorides, and/or other halides.
- 86. A method for making a high energy beam-sensitive (HEBS) glass article, said glass article comprising an integral ion-exchanged surface layer (IIES layer) having silver ions therein, and/or silver halide-containing and/or Ag.sub.2 O-containing and/or silver ion-containing microcrystals and/or microphases therein, containing silanol groups and/or water having a concentration of more than 0.01% by weight H.sub.2 O, which comprises the steps:
- (a) contacting the surface of a parent glass article with an acidic aqueous solution containing silver ions, the parent glass article being prepared from a glass batch melt and having glass composition comprising at least one alkali metal oxide selected from the group consisting of Li.sub.2 O, Na.sub.2 O, K.sub.2 O, Cs.sub.2 O and Rb.sub.2 O, zero up to saturation of halide in the glass melt, and SiO.sub.2, the glass composition containing an effective amount of photosensitivity inhibitors to suppress and/or eliminate photo reduction of said silver ions and/or said silver halide containing and/or said Ag.sub.2 O-containing and/or said silver ion containing microcrystals and/or microphases in said IIES layer, and to render the IIES layer substantially photoinsensitive to substantially all actinic radiation having a wavelength longer than 400 nm,
- (b) heating said parent glass article together with said actinic aqueous solution containing silver ions in contact therewith to reaction temperatures sufficient to effect an exchange of silver ions for said alkali metal ions in the surface of said parent glass article for a period of time sufficient to allow the ion exchange reactions to proceed up to 10 micrometer in thickness dimension into the surface of said parent glass article to form the IIES layer.
- 87. A method according to claim 86 wherein, said IIES layer having been darkened with a high energy beam, recorded image being formed in the darkened IIES layer through bit-by-bit heat-erasing in a predetermined pattern, portions of said darkened layer to produce the recorded image using a high intensity light beam which is absorbed by the high-energy-beam-darkened IIES layer and/or by the glass constituents of the IIES layer.
- 88. A method for making a high energy beam-darkened integral ion exchanged surface layer capable of data storage using bit by bit heat-erasure mode of recording, prior to darkening by exposure to a high energy beam, the undarkened integral ion exchanged surface layer (IIES layer) having silver ions therein and/or silver halide containing and/or Ag.sub.2 O-containing and/or silver ion-containing microcrystals and/or microphases therein, containing silanol groups and/or water having a concentration of more than 0.01% by weight H.sub.2 O, said IIES layer having a thickness of less than 10 micrometers and the darkened IIES layer having an information bearing optical density of more than 1.2 for at least one wavelength, which comprises the steps:
- (a) contacting the surface of a parent glass article with an acidic aqueous solution containing silver ions, the parent glass article being prepared from a glass batch melt and having glass composition comprising at least one alkali metal oxide selected from the group consisting of Li.sub.2 O, Na.sub.2 O, K.sub.2 O, Cs.sub.2 O and Rb.sub.2 O, zero up to saturation of halide in the glass melt, and SiO.sub.2, the glass composition containing an effective amount of photosensitivity inhibitors to suppress and/or eliminate photo reduction of said silver ions and/or said silver halide containing and/or said Ag.sub.2 O-containing and/or said silver ion containing microcrystals and/or microphases in said IIES layer, and to render the IIES layer substantially photoinsensitive to substantially all actinic radiation having a wavelength longer than 400 nm,
- (b) heating said parent glass article together with said acidic aqueous solution containing silver ions in contact therewith to reaction temperatures to effect an exchange of silver ions for said alkali metal ions in the surface of said parent glass article for a period of time sufficient to allow the ion exchange reactions to proceed to less than 10 micrometers in thickness dimension into the surface of said parent glass article to form the IIES layer, and
- (c) darkening said IIES layer to an optical density of more than 1.2 for at least one wavelength using the high energy beam.
- 89. A method according to claim 88 wherein the information bearing optical density is more than 3.0 for at least one wavelength.
- 90. A method according to claim 88 wherein the thickness of the IIES layer is less than 3 micrometer.
- 91. A method according to claim 88 wherein said high energy beam being a high voltage electron beam, an ion beam, an atomic beam, a molecular beam, x-ray radiation or uv radiation having wavelengths shorter than 400 nm.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. application Ser. No. 07/308,187, filed Feb. 7, 1989, on HIGH ENERGY BEAM SENSITIVE GLASSES by Che-Kuang Wu, now abandoned. This application is also a continuation-in-part of U.S. application Ser. No. 07/057,349, filed June 1, 1987, on HIGH ENERGY BEAM SENSITIVE GLASSES by Che-Kuang Wu, now U.S. Pat. No. 4,894,303 which is a divisional application of U.S. application Ser. No. 619,809, filed June 24, 1984, on HIGH ENERGY BEAM SENSITIVE GLASSES by Che-Kuang Wu, now U.S. Pat. No. 4,670,366, which is a continuation-in-part of application Ser. No. 507,681, filed June 24, 1983, on HIGH ENERGY BEAM COLORED GLASSES EXHIBITING INSENSITIVITY TO ACTINIC RADIATION by Che-Kuang Wu, now U.S. Pat. No. 4,567,104. These four prior applications are incorporated herein by reference.
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Divisions (1)
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Number |
Date |
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Parent |
619809 |
Jun 1984 |
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Continuation in Parts (2)
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Number |
Date |
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Parent |
308187 |
Feb 1989 |
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Parent |
507681 |
Jun 1983 |
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