Patent US2176316A successfully refreshed from Google Patents.
US4156039A
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US
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Sodium percarbonate particles (A)
Assignee: Evonik Operations GmbH
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Filing: 1977-09-27
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Granted: 1979-05-22
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Expires: 1997-09-27
Abstract
Abstract There are prepared sodium percarbonate particles comprising a sodium percarbonate nucleus encased in a layer of dehydrated sodium perborate or a mixture of dehydrated sodium perborate and sodium silicate with or without additional water binding materials chemically inert to sodium percarbonate and dehydrated sodium perborate.
Inventors
- 👤 Hans Klebe
- 👤 Gerd Knippschild
- 👤 Hubert Schuster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:43
CPC Classifications
C; C11; C11D; C11D3/00; C11D3/39; C11D3/3942; C01; C01B; C01B15/00; C01B15/055; C01B15/10; C01B15/106
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
102 words
Sodium percarbonate particles consisting of essentially a sodium percarbonate nucleus and an encasing layer consisting essentially of (1) dehydrated sodium perborate containing less than 54 grams of water per mole, (2) dehydrated sodium perborate containing less than 54 grams of water per mole and sodium silicate, or (3) dehydrated sodium perborate containing less than 54 grams of water per mole, sodium silicate and a water binding material chemically inert to sodium percarbonate and said dehydrated sodium perborate, said water binding material being selected from the group consisting of sodium tripolyphosphate, calcined soda, water free sodium sulfate, sodium percarbonate dust and mixture thereof.
Claim 2
Dependent Claim
102 words
Sodium percarbonate particles consisting of essentially a sodium percarbonate nucleus and an encasing layer consisting essentially of (1) dehydrated sodium perborate containing less than 54 grams of water per mole, (2) dehydrated sodium perborate containing less than 54 grams of water per mole and sodium silicate, or (3) dehydrated sodium perborate containing less than 54 grams of water per mole, sodium silicate and a water binding material chemically inert to sodium percarbonate and said dehydrated sodium perborate, said water binding material being selected from the group consisting of sodium tripolyphosphate, calcined soda, water free sodium sulfate, sodium percarbonate dust and mixture thereof.
Claim 3
Dependent Claim
16 words
Sodium percarbonate particles according to claim 1 wherein the active oxygen content is at least 10.2%.
Claim 4
Dependent Claim
80 words
Sodium percarbonate particles according to claim 1 wherein the encasing layer consists essentially of: (a) dehydrated sodium perborate (b) a mixture of dehydrated sodium perborate and sodium silicate containing 14 to 83% of the dehydrated sodium perborate based on the total of the two materials, or (c) a mixture of 5 to 80% dehydrated sodium perborate, 0.1 to 10% of the sodium silicate and 15 to 90% of the water binding agent based on the total of all three components.
Claim 5
Dependent Claim
16 words
The process of claim 1 including the step of at least partially removing the applied water.
Claim 6
Dependent Claim
25 words
Sodium percarbonate particles according to claim 1 consisting essentially of a sodium percarbonate nucleus and an encasing layer consisting essentially of said dehydrated sodium perborate.
Claim 7
Dependent Claim
32 words
A process for the production of the particles of claim 5 consisting essentially of coating water wet sodium percarbonate with dehydrated sodium perborate containing less than 54 grams of water per mole.
Claim 8
Dependent Claim
28 words
Sodium percarbonate particles according to claim 1 consisting essentially of a sodium percarbonate nucleus and an encasing layer consisting essentially of said dehydrated sodium perborate and sodium silicate.
Claim 9
Dependent Claim
29 words
Sodium percarbonate particles according to claim 7 wherein the amount of sodium silicate is such as to provide an SiO 2 content of 0.05 to 5% in the particles.
Claim 10
Dependent Claim
27 words
Sodium percarbonate particles according to claim 7 wherein the sodium silicate is selected from the group consisting of sodium metasilicate, sodium disilicate, sodium ortho silicate and waterglass.
Claim 11
Dependent Claim
38 words
A process for the production of the particles of claim 7 consisting essentially of coating sodium percarbonate particles wet with an aqueous sodium silicate solution with dehydrated sodium perborate containing less than 54 grams of water per mole.
Claim 12
Dependent Claim
40 words
A process for the production of the particles of claim 7 consisting essentially of coating sodium percarbonate particles wet with water with a mixture of dehydrated sodium perborate containing less than 54 grams of water per mole and sodium silicates.
Claim 13
Dependent Claim
48 words
Sodium percarbonate particles according to claim 1 consisting essentially of a sodium percarbonate nucleus and an encasing layer consisting essentially of (1) said dehydrated sodium perborate or (2) said dehydrated sodium perborate and sodium silicate, the total content of active oxygen in the particles being 11 to 15.5%.
Claim 14
Dependent Claim
23 words
Sodium percarbonate particles according to claim 12 wherein the encasing layer is (2) and the sodium silicate is sodium meta silicate or waterglass.
Claim 15
Dependent Claim
17 words
Sodium percarbonate particles according to claim 12 having a total active oxygen content of at least 15%.
Claim 16
Dependent Claim
13 words
Sodium percarbonate particles according to claim 1 wherein the encasing layer is (3).
Claim 17
Dependent Claim
51 words
A process for preparing the product of claim 15 consisting essentially of wetting the sodium percarbonate nucleus with aqueous sodium silicate solution and then applying a solid mixture of dehydrated sodium perborate containing less than 54 grams of water per mole and said water binding material to the wet sodium percarbonate.
Claim 18
Dependent Claim
19 words
Sodium percarbonate particles according to claim 15 wherein there is a total active oxygen content of 8 to 15%.
Claim 19
Dependent Claim
29 words
Sodium percarbonate particles according to claim 17 wherein the amount of sodium silicate is such as to provide an SiO 2 content of 0.05 to 5% in the particles.
Claim 20
Dependent Claim
15 words
Sodium percarbonate particles according to claim 18 wherein the water binding material is sodium percarbonate.
Claim 21
Dependent Claim
15 words
Sodium percarbonate particles according to claim 18 wherein the water binding material is sodium tripolyphosphate.
Claim 22
Dependent Claim
23 words
Sodium percarbonate particles according to claim 18 wherein the encasing layer is made from the dehydrated sodium perborate, waterglass and sodium percarbonate dust.
Claim 23
Dependent Claim
21 words
Sodium percarbonate particles according to claim 18 wherein the dehydrated sodium perborate has an active oxygen content of at least 15%.
Claim 24
Dependent Claim
15 words
Sodium percarbonate particles according to claim 18 wherein the water binding material is calcined soda.
Claim 25
Dependent Claim
15 words
Sodium percarbonate particles according to claim 18 wherein the water binding material is sodium sulfate.
References Cited (Backward Citations)
US3979318A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-05-21 | 1982-11-20 | 1983-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-21 | 1986-11-20 | 1987-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-21 | 1990-11-20 | 1991-05-22 | $7700.00 | Window Closed / Lapsed |