Patent US4013232A successfully refreshed from Google Patents.
US4013232A
Expired / Lapsed
US
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Dispersion of pigments by cryogenic attrition
Assignee: National Research Development Corp UK
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Filing: 1976-01-06
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Granted: 1977-03-22
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Expires: 1996-01-06
Abstract
Abstract In order to disperse a pigmented filtercake, i.e. break up the pigment into fine particles suspended in water, a mixture of filtercake, water and a stabilizer are subjected to ice particles. The mixture of ice particles, filtercake and water are then agitated and the particles of ice act as an abrasive to break up and disperse the pigment. The stabilizer prevents the dispersed particles from re-agglomerating. The process is continuous in that the water is bled off and flowed through an ice flaker where the ice particles are formed preparatory to return to the mixture, all until the dispersion has reached the desired degree.
Inventors
- 👤 Lewis Broughton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:47
CPC Classifications
C; C09; C09B; C09B67/00; C09B67/0001; C09B67/0002
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
59 words
A method of forming a dispersion of an organic pigment in water consisting of the steps: first, forming a water-containing filter cake and reducing it to a fluid mass, second, adding a surface-active stabilizing agent to the fluid mass, third, causing a portion of the water present to freeze for forming ice particles, fourth, agitating the pigment-water-stabilizing agent-ice mixture.
Claim 2
Independent Claim
59 words
A method of forming a dispersion of an organic pigment in water consisting of the steps: first, forming a water-containing filter cake and reducing it to a fluid mass, second, adding a surface-active stabilizing agent to the fluid mass, third, causing a portion of the water present to freeze for forming ice particles, fourth, agitating the pigment-water-stabilizing agent-ice mixture.
Claim 3
Dependent Claim
16 words
The method according to claim 1, wherein agitation is performed by rotation of a cavitation impeller.
Claim 4
Dependent Claim
14 words
The method according to claim 1, wherein the surface active stabilising agent is polyvinylpyrrolidone.
Claim 5
Dependent Claim
17 words
The method according to claim 1, wherein the surface active stabilising agent is Hydroxy Propyl Methyl Cellulose.
Claim 6
Dependent Claim
34 words
The method as claimed in claim 1, wherein, the fluidised filtercake is placed in a vacuum tight cell and vacuum applied to effect freezing of part of the water present to form ice particles.
Claim 7
Dependent Claim
59 words
In the method according to claim 1, wherein the said pigmented filter cake is continuously reduced into the said fluid mass by agitating it and subjecting it to the shearing forces of a rotary mixer, and wherein the liquid of the fluid mass is continuously separated out and frozen and returned in the form of the said ice particles.
Claim 8
Dependent Claim
21 words
In the method according to claim 6, wherein the said liquid is formed into ice particles in a flake ice machine.
Claim 9
Independent Claim
60 words
A method of treating an organic pigment in a water-containing filtercake form for making a dispersion thereof in water consisting of the steps: first, adding a surface-active stabilizing agent to the filtercake, second, forming the filtercake into a fluid mass, third, causing a portion of the water present to freeze for forming ice particles, fourth, agitating the pigment-water-stabilizing agent-ice mixture.
Claim 10
Independent Claim
60 words
A method of treating an organic pigment in a water-containing filtercake form for making a dispersion thereof in water consisting of the steps: first, adding a surface-active stabilizing agent to the filtercake, second, forming the filtercake into a fluid mass, third, causing a portion of the water present to freeze for forming ice particles, fourth, agitating the pigment-water-stabilizing agent-ice mixture.
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) | 1980-03-21 | 1980-09-20 | 1981-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-21 | 1984-09-20 | 1985-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-21 | 1988-09-20 | 1989-03-22 | $7700.00 | Window Closed / Lapsed |