US4786325A
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Cerium/rare earth polishing compositions
Assignee: Rhone Poulenc Specialites Chimiques
•
Filing: 1986-07-21
•
Granted: 1988-11-22
•
Expires: 2006-07-21
Abstract
Abstract Glass polishing compositions, advantageously recycled into glassmaking formulations, are comprised of suspension of particulate ceric oxide and at least one colorless oxide of a lanthanide or yttrium rare earth, preferably an oxide of lanthanum, samarium, europium, gadolinium, dysprosium, thulium, ytterbium, lutecium, yttrium, or mixtures thereof.
Inventors
- 👤 Pierre Melard
- 👤 Francis Tastu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:15
CPC Classifications
C; C03; C03C; C03C1/00; C03C1/002; C09; C09K; C09K3/00; C09K3/14; C09K3/1454
Claims Analysis
Total Claims: 88
Claim 1
Independent Claim
128 words
A process for the preparation of a polishing composition of matter, consisting essentially of (i) simultaneously and continuously intimately admixing a solution of a cerium salt that comprises an aqueous solution of at least one of cerous chloride, cerous nitrate, and ceric nitrate, a basic solution selected from the group consisting of ammonia, sodium or potassium hydroxide and a solution of at least one salt of a trivalent lanthanide or yttrium rare earth, the oxide of which is colorless, with the number of equivalents of base being at least equal to the number of equivalents of cerium and rare earth values and the pH of the reaction medium being greater than 6, (ii) filtering the precipitate which results, (iii) drying said precipitate, and (iv) thence calcining said precipitate.
Claim 2
Dependent Claim
128 words
A process for the preparation of a polishing composition of matter, consisting essentially of (i) simultaneously and continuously intimately admixing a solution of a cerium salt that comprises an aqueous solution of at least one of cerous chloride, cerous nitrate, and ceric nitrate, a basic solution selected from the group consisting of ammonia, sodium or potassium hydroxide and a solution of at least one salt of a trivalent lanthanide or yttrium rare earth, the oxide of which is colorless, with the number of equivalents of base being at least equal to the number of equivalents of cerium and rare earth values and the pH of the reaction medium being greater than 6, (ii) filtering the precipitate which results, (iii) drying said precipitate, and (iv) thence calcining said precipitate.
Claim 3
Dependent Claim
25 words
The process as defined by claim 1, wherein the concentration of the solution of the cerium salt ranges from 0.2 to 4 moles per liter.
Claim 4
Dependent Claim
38 words
The process as defined by claim 2, wherein the cerium is introduced into the reaction medium in the cerous state and is thereafter oxidized to the ceric state by continuously adding an oxidizing agent to said reaction medium.
Claim 5
Dependent Claim
39 words
The process as defined by claim 3, said oxidation being carried out by means of an oxidizing agent comprising a solution of sodium, potassium or ammonium perchlorate, chlorate, hypochlorate, persulfate, hydrogen peroxide, air, oxygen, ozone, or by electrochemical oxidation.
Claim 6
Dependent Claim
24 words
The process as defined by claim 4, said oxidizing agent comprising an about 10 to 40% stoichiometric excess with respect to said cerous salt.
Claim 7
Dependent Claim
41 words
The process as defined by claim 1, wherein said solution of said at least one salt of said trivalent rare earth comprises an aqueous solution of a chloride or nitrate of lanthanum, samarium, europium, gadolinium, dysprosium, thulium, ytterbium, lutecium and yttrium.
Claim 8
Dependent Claim
33 words
The process as defined by claim 6, wherein the concentration of the aqueous solution of the at least one salt of said trivalent rare earth ranges from 0.2 to 4 moles per liter.
Claim 9
Dependent Claim
24 words
The process as defined by claim 1, wherein said basic solution comprises an aqueous solution of ammonium, sodium or potassium hydroxide, or sodium carbonate.
Claim 10
Dependent Claim
18 words
The process as defined by claim 8, the normality of said basic solution ranging from 1 to 5N.
Claim 11
Dependent Claim
34 words
The process as defined by claim 8, the reaction medium comprising an at least 5% stoichiometric excess of equivalents of base with respect to the number of equivalents of cerium and rare earth values.
Claim 12
Dependent Claim
19 words
The process as defined by claim 8, wherein the pH of the reaction medium ranges from 6 to 10.
Claim 13
Dependent Claim
19 words
The process as defined by claim 11, wherein the pH of the reaction medium ranges from 7 to 9.
Claim 14
Dependent Claim
20 words
The process as defined by claim 11, wherein the pH of the reaction medium is controlled within ±0.1 pH units.
Claim 15
Dependent Claim
22 words
The process as defined by claim 1, wherein the holding time in the step (i) ranges from 30 minutes to 2 hours.
Claim 16
Dependent Claim
22 words
The process as defined by claim 14, wherein the temperature of the step (i) reaction medium ranges from 10° to 95° C.
Claim 17
Dependent Claim
22 words
The process as defined by claim 15, wherein the temperature of the step (i) reaction medium ranges from 20° to 70° C.
Claim 18
Dependent Claim
32 words
The process as defined by claim 15 further comprising aging the reaction mass prior to filtering at a temperature ranging from 10° to 95° C. for from 30 minutes to 2 hours.
Claim 19
Dependent Claim
16 words
The process as defined by claim 17, said aging temperature ranging from 20° to 80° C.
Claim 20
Dependent Claim
18 words
The process as defined by claim 15, wherein said filtering step (ii) is carried out at ambient temperature.
Claim 21
Dependent Claim
36 words
The process as defined by claim 1, wherein the filter cake resulting from said step (ii) is washed with water, following which the water content of such filter cake ranges from 20 to 80% by weight.
Claim 22
Dependent Claim
21 words
The process as defined by claim 20, the water content of such filter cake ranging from 30 to 50% by weight.
Claim 23
Dependent Claim
211 words
The process as defined by claim 1, said step (i) consisting essentially of (ia) simultaneously and continuously intimately admixing, at a temperature ranging from 40° to 95° C., a solution of a cerium salt, a basic solution selected from the group consisting of ammonium, sodium or potassium hydroxide and a solution of at least one salt of a trivalent lanthanide or yttrium rare earth, the oxide of which is colorless, with the number of equivalents of base being at least equal to the number of equivalents of cerium and rare earth values and the pH of the reaction medium being greater than 6, (ib) simultaneously and continuously intimately admixing, at a temperature ranging from 10° to 25° C., a solution of a cerium salt, a basic solution and a solution of at least one salt of a trivalent lanthanide or yttrium rare earth, the oxide of which is colorless, with the number of equivalents of base being at least equal to the number of equivalents of cerium and rare earth values and the pH of the reaction medium being greater than 6, (iia) intimately admixing the respective precipitates which result, either prior to or after said filtering step (ii), (iii) drying said precipitate admixture, and (iv) thence calcining said precipitate admixture.
Claim 24
Dependent Claim
17 words
The process as defined by claim 22, said step (ia) temperature ranging from 40° to 60° C.
Claim 25
Dependent Claim
15 words
The process as defined by claim 22, said step (ib) temperature being about 20° C.
Claim 26
Dependent Claim
36 words
The process as defined by claim 22, comprising aging the step (ia) and step (ib) reaction media, or mixture thereof, at a temperature ranging from 10° to 95° C. for from 30 minutes to 2 hours.
Claim 27
Dependent Claim
16 words
The process as defined by claim 25, said aging temperature ranging from 20° to 70° C.
Claim 28
Dependent Claim
55 words
The process as defined by claim 25, comprising (iia) intimately admixing aqueous suspensions of the respective precipitates, either prior to or after the aging thereof, such that the step (ib) precipitate provides from 10 to 75% by weight of the total amount of rare earth values in the product composition, expressed as the oxides thereof.
Claim 29
Dependent Claim
35 words
The process as defined by claim 26, said step (ib) precipitate providing from 25 to 75% by weight of the total amount of rare earth values in the product composition, expressed as the oxides thereof.
Claim 30
Dependent Claim
32 words
The process as defined by claim 26, further comprising washing the filter cake with water, the water content of said filter cake, after washing, ranging from about 20 to 80% by weight.
Claim 31
Dependent Claim
18 words
The process as defined by claim 20, said water content ranging from about 30 to 50% by weight.
Claim 32
Dependent Claim
42 words
The process as defined by claim 25, comprising separately filtering the respective precipitates, with said step (ib) precipitate providing from 10 to 75% by weight of the total amount of rare earth values in the product composition, expressed as the oxides thereof.
Claim 33
Dependent Claim
35 words
The process as defined by claim 31, said step (ib) precipitate providing from 25 to 75% by weight of the total amount of rare earth values in the product composition, expressed as the oxides thereof.
Claim 34
Dependent Claim
27 words
The process as defined by claim 1, comprising drying the precipitate at a temperature ranging from 100° to 600° C. for from 30 minutes to 2 hours.
Claim 35
Dependent Claim
28 words
The process as defined by claim 1, comprising calcining said dried precipitate at a temperature ranging from 600° to 1200° C. for from 30 minutes to 10 hours.
Claim 36
Dependent Claim
17 words
The process as defined by claim 34, said temperature of calcination ranging from 950° to 1150° C.
Claim 37
Dependent Claim
19 words
The process as defined by claim 1, further comprising grinding and classifying the product composition after the calcination thereof.
Claim 38
Dependent Claim
37 words
In the polishing of a glassy substrate by lapping same using an abrasive composition, the improvement which comprises, utilizing as the abrasive composition therefor, a liquid suspension of the composition of matter as defined by claim 27.
Claim 39
Dependent Claim
14 words
The polishing as defined by claim 37, the glassy substrate comprising a television screen.
Claim 40
Dependent Claim
28 words
The polishing composition as defined by claim 27, wherein the polishing composition is a glass polishing composition which can be recycled as a raw material for the glass.
Claim 41
Dependent Claim
26 words
The process as defined by claim 1, wherein the polishing composition of matter formed can be used as a raw material in the formation of glass.
Claim 42
Dependent Claim
113 words
A polishing composition capable of being recycled into glass, provided by a process consisting essentially of (i) simultaneously and continuously intimately admixing a solution of a cerium salt, a basic solution selected from the group consisting of ammonia, sodium or potassium hydroxide and a solution of at least one salt of a trivalent lanthanide or yttrium rare earth, the oxide of which is colorless, with the number of equivalents of base being at least equal to the number of equivalents of cerium and rare earth values and the pH of the reaction medium being greater than 6, (ii) filtering the precipitate which results, (iii) drying said precipitate, and (iv) thence calcining said precipitate.
Claim 43
Dependent Claim
113 words
A polishing composition capable of being recycled into glass, provided by a process consisting essentially of (i) simultaneously and continuously intimately admixing a solution of a cerium salt, a basic solution selected from the group consisting of ammonia, sodium or potassium hydroxide and a solution of at least one salt of a trivalent lanthanide or yttrium rare earth, the oxide of which is colorless, with the number of equivalents of base being at least equal to the number of equivalents of cerium and rare earth values and the pH of the reaction medium being greater than 6, (ii) filtering the precipitate which results, (iii) drying said precipitate, and (iv) thence calcining said precipitate.
Claim 44
Dependent Claim
29 words
The polishing composition as defined by claim 41, wherein the solution of the cerium salt comprises an aqueous solution of cerous chloride, cerous nitrate, ceric nitrate, or mixture thereof.
Claim 45
Dependent Claim
26 words
The polishing composition as defined by claim 41, wherein the concentration of the solution of the cerium salt ranges from 0.2 to 4 moles per liter.
Claim 46
Dependent Claim
39 words
The polishing composition as defined by claim 43, wherein the cerium is introduced into the reaction medium in the cerous state and is thereafter oxidized to the ceric state by continuously adding an oxidizing agent to said reaction medium.
Claim 47
Dependent Claim
40 words
The polishing composition as defined by claim 44, said oxidation being carried out by means of an oxidizing agent comprising a solution of sodium, potassium or ammonium perchlorate, chlorate, hypochlorate, persulfate, hydrogen peroxide, air, oxygen, oxzone, or by electrochemical oxidation.
Claim 48
Dependent Claim
25 words
The polishing composition as defined by claim 44, said oxidizing agent comprising about an 10 to 40% stoichiometric excess with respect to said cerous salt.
Claim 49
Dependent Claim
42 words
The polishing composition as defined by claim 41, wherein said solution of said at least one salt of said trivalent rare earth comprises an aqueous solution of a chloride or nitrate of lanthanum, samarium, europium, gadolinium, dysprosium, thulium, ytterbium, luctecium or yttrium.
Claim 50
Dependent Claim
34 words
The polishing composition as defined by claim 47, wherein the concentration of the aqueous solution of the at least one salt of said trivalent rare earth ranges from 0.2 to 4 moles per liter.
Claim 51
Dependent Claim
19 words
The polishing composition as defined by claim 41, the normality of said basic solution ranging from 1 to 5N.
Claim 52
Dependent Claim
35 words
The polishing composition as defined by claim 41, the reaction medium comprising an at least 5% stiochiometric excess of equivalents of base with respect to the number of equivalents of cerium and rare earth values.
Claim 53
Dependent Claim
20 words
The polishing composition as defined by claim 41, wherein the pH of the reaction medium ranges from 6 to 10.
Claim 54
Dependent Claim
20 words
The polishing composition as defined by claim 51, wherein the pH of the reaction medium ranges from 7 to 9.
Claim 55
Dependent Claim
21 words
The polishing composition as defined by claim 51, wherein the pH of the reaction medium is controlled within ±0.1 pH units.
Claim 56
Dependent Claim
23 words
The polishing composition as defined by claim 41, wherein the holding time in the step (i) ranges from 30 minutes to 2 hours.
Claim 57
Dependent Claim
23 words
The polishing composition as defined by claim 54, wherein the temperature of the step (i) reaction medium ranges from 10° to 95° C.
Claim 58
Dependent Claim
23 words
The polishing composition as defined by claim 55, wherein the temperature of the step (i) reaction medium ranges from 20° to 70° C.
Claim 59
Dependent Claim
33 words
The polishing composition as defined by claim 55, further comprising aging the reaction mass prior to filtering at a temperature ranging from 10° to 95° C. for from 30 minutes to 2 hours.
Claim 60
Dependent Claim
17 words
The polishing composition as defined by claim 57, said aging temperature ranging from 20° to 80° C.
Claim 61
Dependent Claim
19 words
The polishing composition as defined by claim 55, wherein said filtering step (ii) is carried out at ambient temperature.
Claim 62
Dependent Claim
37 words
The polishing composition as defined by claim 41, wherein the filter cake resulting from said step (ii) is washed with water, following which the water content of such filter cake ranges from 20 to 80% by weight.
Claim 63
Dependent Claim
22 words
The polishing composition as defined by claim 60, the water content of such filter cake ranging from 30 to 50% by weight.
Claim 64
Dependent Claim
214 words
The polishing composition as defined by claim 41, wherein said step (i) consisting essentially of (ia) simultaneously and continuously intimately admixing, at a temperature ranging from 40° to 95° C., a solution of a cerium salt, a basic solution selected from the group consisting of ammonium or sodium or potassium hydroxide, and a solution of at least one salt of a trivalent lanthanide or yttrium rare earth, the oxide of which is colorless, with the number of equivalents of base being at least equal to the number of equivalents of cerium and rare earth values and the pH of the reaction medium being greater than 6, (ib) simultaneously and continuously intimately admixing, at a temperature ranging from 10° to 25° C., a solution of a cerium salt, a basic solution and a solution of at least one salt of a trivalent lanthanide or yttrium rare earth, the oxide of which is colorless, with the number of equivalents of base being at least equal to the number of equivalents of cerium and rare earth values and the pH of the reaction medium being greater than 6, (iia) intimately admixing the respective precipitates which result, either prior to or after said filtering step (ii), (iii) drying said precipitate admixture, and (iv) thence calcining said precipitate admixture.
Claim 65
Dependent Claim
18 words
The polishing composition as defined by claim 62, said step (ia) temperature ranging from 40° to 60° C.
Claim 66
Dependent Claim
16 words
The polishing composition as defined by claim 62, said step (ib) temperature being about 20° C.
Claim 67
Dependent Claim
38 words
The polishing composition as defined by claim 62, comprising aging the step (ia) and the step (ib) reaction medium, or mixture thereof, at a temperature ranging from 10° to 95° C. for from 30 minutes to 2 hours.
Claim 68
Dependent Claim
17 words
The polishing composition as defined by claim 65, said aging temperature ranging from 20° to 70° C.
Claim 69
Dependent Claim
56 words
The polishing composition as defined by claim 65, comprising (iia) intimately admixing aqueous suspensions of the respective precipitates, either prior to or after the aging thereof, such that the step (ib) precipitate provides from 10 to 75% by weight of the total amount of rare earth values in the product composition, expressed as the oxides thereof.
Claim 70
Dependent Claim
36 words
The polishing composition as defined by claim 67, said step (ib) precipitate providing from 25 to 75% by weight of the total amount of rare earth values in the product composition, expressed as the oxides thereof.
Claim 71
Dependent Claim
33 words
The polishing composition as defined by claim 67, further comprising washing the filter cake with water, the water content of said filter cake, after washing, ranging from about 20 to 80% by weight.
Claim 72
Dependent Claim
19 words
The polishing composition as defined by claim 69, said water content ranging from about 30 to 50% by weight.
Claim 73
Dependent Claim
43 words
The polishing composition as defined by claim 65, comprising separately filtering the respective precipitates, with said step (ib) precipitate providing from 10 to 75% by weight of the total amount of rare earth values in the product composition, expressed as the oxides thereof.
Claim 74
Dependent Claim
36 words
The polishing composition as defined by claim 71, said step (ib) precipitate providing from 25 to 75% by weight of the total amount of rare earth values in the product composition, expressed as the oxides thereof.
Claim 75
Dependent Claim
28 words
The polishing composition as defined by claim 41, comprising drying the precipitate at a temperature ranging from 100° to 600° C. for from 30 minutes to 2 hours.
Claim 76
Dependent Claim
29 words
The polishing composition as defined by claim 41, comprising calcining said dried precipitate at a temperature ranging from 600° to 1200° C. for from 30 minutes to 10 hours.
Claim 77
Dependent Claim
18 words
The polishing composition as defined by claim 74, said temperature of calcination ranging from 950° to 1150° C.
Claim 78
Dependent Claim
20 words
The polishing composition as defined by claim 71, further comprising grinding and classifying the product composition after the calcination thereof.
Claim 79
Dependent Claim
18 words
The polishing composition as defined by claim 41, wherein said at least one colorless oxide comprises lanthanum sesquioxide.
Claim 80
Dependent Claim
21 words
The polishing composition as defined by claim 41, having a BET specific surface ranging from 2 to 10 m 2 /g.
Claim 81
Dependent Claim
17 words
The polishing composition as defined by claim 78, having particles sizes ranging from 0.2 to 5.0 m.
Claim 82
Dependent Claim
19 words
The polishing composition as defined by claim 79, having a mean particle diameter ranging from 0.5 to 1.5 m.
Claim 83
Dependent Claim
33 words
The polishing composition as defined by claim 79, comprising from 40 to 99.5% by weight of said ceric oxide and from 0.5 to 60% by weight of said at least one colorless oxide.
Claim 84
Dependent Claim
33 words
The polishing composition as defined by claim 81, comprising from 85 to 98% by weight of said ceric oxide and from 2 to 15% by weight of said at least one colorless oxide.
Claim 85
Dependent Claim
19 words
A polishing composition comprising a homogeneous suspension, in water, of the composition of matter as defined by claim 41.
Claim 86
Dependent Claim
19 words
A polishing composition comprising a homogeneous suspension, in water, of the composition of matter as defined by claim 81.
Claim 87
Dependent Claim
26 words
The polishing composition as defined by claim 84, having a concentration, in soft water and expressed as CeO 2 , ranging from 30 to 200 g/liter.
Claim 88
Dependent Claim
17 words
The polishing composition as defined by claim 85, said soft water having hardness of less than 30°TH.
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) | 1991-11-22 | 1992-05-23 | 1992-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-22 | 1996-05-23 | 1996-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-22 | 2000-05-23 | 2000-11-22 | $7700.00 | Window Closed / Lapsed |