US5152835A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite titania-calcined kaolin opacifying pigments and method for making and using same
Assignee: BASF Corp
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Filing: 1991-05-08
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Granted: 1992-10-06
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Expires: 2011-05-08
Abstract
Abstract Novel titania-calcined kaolin composite pigments wherein structuring and adhesion of titania and calcined kaolin particles is achieved by use of a cationic polyelectrolyte. Methods for compositing titania and calcined kaolin pigments which feature the presence of at least one polyanionic dispersant (such as sodium polyacrylate, sodium silicate, sodium condensed phosphate or mixtures thereof) in the pigment slurry into which cationic polyelectrolyte is introduced and the use of strongly alkaline pH (e.g., above 9).
Inventors
- 👤 Saad Nemeh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:16
CPC Classifications
C; C09; C09C; C09C1/00; C09C1/0081; C09C1/0084; C09C1/0087; C01; C01P; C01P2002/00; C01P2002/80; C01P2002/84; C01P2004/00; C01P2004/50; C01P2004/51; C01P2004/60; C01P2004/61; C01P2004/62; C01P2004/80; C01P2006/00; C01P2006/21; C01P2006/22; C01P2006/60; C01P2006/80
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
29 words
A composite opacifying pigment comprising particles of titania pigment and particles of calcined kaolin coflocculated and bound together in the form of coherent aggregates by an organic cationic polyelectrolyte.
Claim 2
Dependent Claim
29 words
A composite opacifying pigment comprising particles of titania pigment and particles of calcined kaolin coflocculated and bound together in the form of coherent aggregates by an organic cationic polyelectrolyte.
Claim 3
Dependent Claim
14 words
The pigment of claim 1 wherein said polyelectrolyte is a quaternary ammonium salt polymer.
Claim 4
Dependent Claim
14 words
The pigment of claim 1 wherein said cationic polyelectrolyte is dimethyl dialkyl ammonium chloride.
Claim 5
Dependent Claim
24 words
The pigment of claim 1 in which said titania and calcined kaolin are coflocculated at a pH in the range of 9.5 to 11.
Claim 6
Dependent Claim
22 words
The pigment of claim 1 wherein the weight ratio of titania to calcined kaolin is in the range of 10:90 to 90:10.
Claim 7
Dependent Claim
22 words
The pigment of claim 1 wherein the weight ratio of titania to calcined kaolin is in the range of 35:65 to 65:35.
Claim 8
Dependent Claim
10 words
The pigment of claim 1 wherein said pigment is rutile.
Claim 9
Dependent Claim
11 words
The pigment of claim 1 wherein said titania pigment is anatase
Claim 10
Dependent Claim
52 words
The pigment of claim 1 wherein the weight ratio of titania to calcined kaolin is in the range of 30:70 to 50:50, and said cationic polyelectrolyte is dimethyl dialkyl ammonium chloride, added in amount in the range of 0.1% to 0.25% based on the combined weight of calcined kaolin and titania pigments.
Claim 11
Independent Claim
137 words
A method for manufacturing a composite opacifying pigment which comprises: providing particles of titania pigment, providing particles of calcined kaolin pigment, mixing said particles together in the presence of water to form a slurry containing a physical admixture of said particles, introducing a water-soluble cationic polyelectrolyte in the presence of water either to said particles of titania pigment, said particles of calcined kaolin pigment or a physical admixture thereof, at a pH above 9 and in the presence of at least one anionic pigment dispersant, a sufficient amount of said cationic polyelectrolyte being added to coflocculate and bind together said particles of titania and said particles of calcined kaolin into unitary coherent particles, and recovering the coflocculated particles of titania pigment and calcined kaolin pigment, and, optionally adding additional anionic pigment dispersant to said coflocculated bulked particles.
Claim 12
Independent Claim
137 words
A method for manufacturing a composite opacifying pigment which comprises: providing particles of titania pigment, providing particles of calcined kaolin pigment, mixing said particles together in the presence of water to form a slurry containing a physical admixture of said particles, introducing a water-soluble cationic polyelectrolyte in the presence of water either to said particles of titania pigment, said particles of calcined kaolin pigment or a physical admixture thereof, at a pH above 9 and in the presence of at least one anionic pigment dispersant, a sufficient amount of said cationic polyelectrolyte being added to coflocculate and bind together said particles of titania and said particles of calcined kaolin into unitary coherent particles, and recovering the coflocculated particles of titania pigment and calcined kaolin pigment, and, optionally adding additional anionic pigment dispersant to said coflocculated bulked particles.
Claim 13
Dependent Claim
26 words
The method of claim 10 wherein sufficient anionic dispersant is present in the recovered coflocculated bulked particles to result in a 50% solids fluid nonsettling slurry.
Claim 14
Dependent Claim
19 words
The method of claim 10 wherein the anionic dispersant is an alkali metal or ammonium salt of a polyacid.
Claim 15
Dependent Claim
25 words
The method claim 10 wherein the anionic dispersant comprises a sodium, potassium or ammonium salt of silicic, phosphoric, acrylic or methacrylic acid or combinations thereof.
Claim 16
Dependent Claim
17 words
The method of claim 10 wherein the anionic dispersant comprises sodium silicate, sodium polyacrylate or mixtures thereof.
Claim 17
Dependent Claim
18 words
The method of claim 10 wherein said anionic dispersant comprises a mixture of sodium silicate and sodium polyacrylate.
Claim 18
Dependent Claim
20 words
The method claim 10 wherein the pH at which coflocculation takes place is in the range of 9.5 to 11.
Claim 19
Dependent Claim
52 words
The method of claim 10 wherein said cationic polyelectrolyte is added to an anionically dispersed aqueous slurry of said particles of titania in amount in excess of that required to flocculate said particles of titania, and particles of calcined kaolin are thereafter mixed with said slurry of titania containing said cationic polyelectrolyte.
Claim 20
Dependent Claim
43 words
The method of claim 10 wherein said cationic polyelectrolyte is added to an anionically dispersed slurry of particles of calcined kaolin clay before an anionically dispersed slurry of said titania is mixed with said particles of titania and before cationic polyelectrolyte is added.
Claim 21
Dependent Claim
25 words
The method of claim 10 wherein said particles of calcined kaolin and said particles of titania are mixed together before said cationic polyelectrolyte is added.
Claim 22
Dependent Claim
26 words
The method of claim 10 wherein the weight ratio of titania to calcined kaolin in the coflocculated mixture is in the range of 10:90 to 90:10.
Claim 23
Dependent Claim
22 words
The method of claim 10 wherein the weight ratio of titania to calcined kaolin is in the range of 35:65 to 65:35.
References Cited (Backward Citations)
US3726700A
Cited
US3846147A
Cited
US4738726A
Cited
WO1991005604A1
Cited
WO1991005745A1
Cited
US5078793A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-10-06 | 1996-04-06 | 1996-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-10-06 | 2000-04-06 | 2000-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-10-06 | 2004-04-06 | 2004-10-06 | $7700.00 | Window Closed / Lapsed |