US3940550A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultrafine natural calcium carbonates as coating pigments in coated papers
Assignee: Omya AG
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Filing: 1973-10-15
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Granted: 1976-02-24
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Expires: 1993-10-15
Abstract
Abstract A coated paper comprising an ultrafine natural calcium carbonate as a pigment, which has an average statistical particle diameter of from 0.5 to 0.7 μm, a maximum diameter of from 3.0 to 4.0 μm, and a specific surface area of at least 12sq.m./g.
Inventors
- 👤 Pierre Delfosse
- 👤 Alfred Bosshard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:35
CPC Classifications
D; D21; D21H; D21H19/00; D21H19/36; D21H19/38; D21H19/385; C; C08; C08K; C08K3/00; C08K3/18; C08K3/24; C08K3/26; C09; C09C; C09C1/00; C09C1/02; D21H21/00; D21H21/50; D21H21/52; C01; C01P; C01P2004/00; C01P2004/51; C01P2004/60; C01P2004/61; C01P2004/62; C01P2006/00; C01P2006/12; C01P2006/60; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/258; Y10T428/31504; Y10T428/31855; Y10T428/3188; Y10T428/31895; Y10T428/31906; Y10T428/31971; Y10T428/31993
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
47 words
Paper coated with a composition comprising an ultrafine natural calcium carbonate as a pigment, said pigment having an average statistical particle diameter of from 0.5 to 0.7 μm, a maximum diameter of from 3.0 to 4.0 μm, and a specific surface area of at least 12 sq.m./g.
Claim 2
Dependent Claim
47 words
Paper coated with a composition comprising an ultrafine natural calcium carbonate as a pigment, said pigment having an average statistical particle diameter of from 0.5 to 0.7 μm, a maximum diameter of from 3.0 to 4.0 μm, and a specific surface area of at least 12 sq.m./g.
Claim 3
Dependent Claim
16 words
Paper according to claim 1, in the form of roll offset paper or sheet offset paper.
Claim 4
Dependent Claim
10 words
Paper according to claim 2, which is a mat paper.
Claim 5
Dependent Claim
14 words
Paper according to claim 1, wherein the pigment is chalk derived from coccolith shells.
Claim 6
Dependent Claim
11 words
Paper according to claim 1, wherein the pigment is crystalline calcite.
Claim 7
Dependent Claim
14 words
Paper according to claim 2, wherein the pigment is chalk derived from coccolith shells.
Claim 8
Dependent Claim
11 words
Paper according to claim 2, wherein the pigment is crystalline calcite.
Claim 9
Dependent Claim
58 words
Paper coated with a pigment composition, comprising a mixture of: 70 parts by weight of kaolin; and 30 parts by weight of an ultrafine natural calcium carbonate having an average statistical particle diameter of from 0.5 to 0.7 μm, a maximum diameter of from 3.0 to 4.0 μm, and a specific surface area of at least 12 sq.m./g.
Claim 10
Dependent Claim
58 words
Paper coated with a pigment composition, comprising a mixture of: 70 parts by weight of kaolin; and 30 parts by weight of an ultrafine natural calcium carbonate having an average statistical particle diameter of from 0.5 to 0.7 μm, a maximum diameter of from 3.0 to 4.0 μm, and a specific surface area of at least 12 sq.m./g.
Claim 11
Dependent Claim
16 words
Paper according to claim 8, wherein the natural calcium carbonate is chalk derived from coccolith sheels.
Claim 12
Dependent Claim
13 words
Paper according to claim 8, wherein the natural calcium carbonate is crystalline calcite.
Claim 13
Dependent Claim
76 words
Paper coated with a pigment composition comprising a mixture of: 25 percent by weight kaolin; 25 percent by weight natural calcium carbonate having approximately 35 percent by weight of particles smaller than 2 μm; and 50 percent by weight of an ultrafine natural calcium carbonate having an average statistical particle diameter of from 0.5 to 0.7 μm, a maximum diameter of from 3.0 to 4.0 μm, and a specific surface area of at least 12 sq.m./g;
Claim 14
Dependent Claim
76 words
Paper coated with a pigment composition comprising a mixture of: 25 percent by weight kaolin; 25 percent by weight natural calcium carbonate having approximately 35 percent by weight of particles smaller than 2 μm; and 50 percent by weight of an ultrafine natural calcium carbonate having an average statistical particle diameter of from 0.5 to 0.7 μm, a maximum diameter of from 3.0 to 4.0 μm, and a specific surface area of at least 12 sq.m./g;
Claim 15
Dependent Claim
17 words
Paper according to claim 11, wherein the ultrafine natural calcium carbonate is chalk derived from coccolith shells.
Claim 16
Dependent Claim
14 words
Paper according to claim 11, wherein the ultrafine natural calcium carbonate is crystalline calcite.
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) | 1979-02-23 | 1979-08-25 | 1980-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-23 | 1983-08-25 | 1984-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-23 | 1987-08-25 | 1988-02-24 | $7700.00 | Window Closed / Lapsed |