US3726700A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite pigments and their preparation
Assignee: EIDP Inc
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Filing: 1971-03-19
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Granted: 1973-04-10
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Expires: 1991-03-19
Abstract
Abstract Composite pigments, exhibiting high hiding power when incorporated into latex paints, are formed of a mineral extender comprising clay particles to which pigmentary titanium dioxide particles have been adhered by a precipitate of 1-15 percent by weight of hydrous oxides of titanium, aluminum, or silicon or mixtures thereof. The clay particles comprising the extender are preferably those derived from high kaolinite clays, or calcined or delaminated clays having an internal pore volume in the dry, compressed form of at least 0.3 cm3/gm and an internal pore size distribution between 1.5 and 0.2 microns.
Inventors
- 👤 H Wildt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:24
CPC Classifications
C; C09; C09C; C09C1/00; C09C1/0081; C09C1/0084; C09C1/0087; C01; C01P; C01P2004/00; C01P2004/20; C01P2004/60; C01P2004/62; C01P2004/80; C01P2006/00; C01P2006/14; C01P2006/16; C01P2006/17; C01P2006/80
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
40 words
The pigment of claim 1 in which the mineral extender consists of a calcined or delaminated high kaolinite clay exhibiting an internal porosity in the dry form of at least 0.3 cm3/gm consisting of pores of 0.2-1.5 microns in diameter.
Claim 2
Dependent Claim
13 words
The pigment of claim 2 in which pores are 0.2-0.8 micron in diameter.
Claim 3
Dependent Claim
36 words
The pigment of claim 1 in which 3-50 percent by weight thereof consists of pigmentary titanium dioxide cooler discharge containing up to 5 percent co-oxidized alumina as obtained from the vapor phase oxidation of titanium tetrachloride.
Claim 4
Independent Claim
117 words
A method of preparing a composite pigment which confers high opacity to latex paints by the steps of: a. forming a water slurry of 100-300 grams per liter of total solids, of which 3-50 percent by weight are pigmentary titanium dioxide particles and 50 to 97 percent by weight is a mineral extender comprising clay particles; b. adding 1-15 percent by weight, based on said particles, of titania, alumina, silica or mixtures thereof as Soluble salts to the aqueous slurry with agitation; c. adjusting the slurry pH to 7.8-8.3 with agitation; d. digesting the slurry for 15-60 minutes; e. filtering the slurry, washing it free of salts, and thereafter subjecting it to drying and fluid energy milling.
Claim 5
Dependent Claim
40 words
The process of claim 5 where the mineral extender consists of a high kaolinite calcined or delaminated clay with an internal porosity as measured in the dry form of at least 0.3 cm3/gm consisting of pores 0.2-1.5 microns in diameter.
Claim 6
Dependent Claim
14 words
The process of claim 6 in which the pores are 0.2-0.8 microns in diameter.
Claim 7
Dependent Claim
40 words
The process of claim 5 wherein step (b) is effected by addition of an alkali metal silicate and a soluble salt of aluminum to provide, respectively, a precipitate of 3 to 10 percent silica and 0.1 to 5 percent alumina.
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) | 1976-04-09 | 1976-10-09 | 1977-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-09 | 1980-10-09 | 1981-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-09 | 1984-10-09 | 1985-04-10 | $7700.00 | Window Closed / Lapsed |