Patent US4915923A successfully refreshed from Google Patents.
US4915923A
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Filler for ink jet recording paper
Assignee: Mizusawa Industrial Chemicals Ltd
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Filing: 1988-06-09
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Granted: 1990-04-10
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Expires: 2008-06-09
Abstract
Abstract Disclosed is a filler for ink jet recording paper, said filler being composed of amorphous silica having a median diameter, measured by the coulter counter method, of 2 to 15 mu m, an oil absorption of at least 180 ml/100 g, a refractive index, measured by the solvent method, of at least 1.450, and a moisture absorption, measured when it is caused to absorb moisture for 200 hours at a relative humidity of 90% and a temperature of 25 DEG C., of at least 35%.
Inventors
- 👤 Masahide Ogawa
- 👤 Teiji Sato
- 👤 Maso Takahashi
- 👤 Toshio Kitsu
- 👤 Seikichi Takahashi
- 👤 Kinichi Ono
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:06
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/50; B41M5/52; B41M5/5218; C; C09; C09C; C09C1/00; C09C1/28; C09C1/30; C09C1/3045; C01; C01P; C01P2002/00; C01P2002/02; C01P2002/80; C01P2002/84; C01P2004/00; C01P2004/51; C01P2004/60; C01P2004/61; C01P2006/00; C01P2006/12; C01P2006/14; C01P2006/19; C01P2006/60; C01P2006/90
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
112 words
A filler for ink jet recording paper, said filler being composed of amorphous silica having (i) a median diameter, measured by the Coulter counter method, of 2 to 15 μm, (ii) an oil absorption of at least 180 ml/100 g, (iii) a refractive index, measured by the solvent method, of at least 1.450, (iv) a specific surface area of 280 to 500 m 2 /g, (v) a pore volume, measured by the nitrogen adsorption method, of more than 1.30 cc/g, and (vi) a moisture absorption, measured when it is caused to absorb moisture for 200 hours at a relative humidity of 90% and a temperature of 25° C., of at least 35%.
Claim 2
Dependent Claim
112 words
A filler for ink jet recording paper, said filler being composed of amorphous silica having (i) a median diameter, measured by the Coulter counter method, of 2 to 15 μm, (ii) an oil absorption of at least 180 ml/100 g, (iii) a refractive index, measured by the solvent method, of at least 1.450, (iv) a specific surface area of 280 to 500 m 2 /g, (v) a pore volume, measured by the nitrogen adsorption method, of more than 1.30 cc/g, and (vi) a moisture absorption, measured when it is caused to absorb moisture for 200 hours at a relative humidity of 90% and a temperature of 25° C., of at least 35%.
Claim 3
Dependent Claim
68 words
The filler of claim 1 wherein the amorphous silica has an acid strength distribution such that the amount of the acid at an acid strength function H 0 of more than +1.5 and up to +3.3 is not more than 0.05 millimole/g, and the amount of the acid at an acid strength function H 0 of more than +3.3 and up to +4.8 is at least 0.20 millimole/g.
Claim 4
Dependent Claim
19 words
The filler of claim 1 wherein the amorphous silica has an oil absorption of 200 to 260 ml/100 g.
Claim 5
Dependent Claim
17 words
The filler of claim 1 wherein the amorphous silica has a refractive index of 1.460 to 1.470.
Claim 6
Dependent Claim
21 words
The filler of claim 1 wherein the pore volume, measured by the nitrogen absorption method, is not greater than 1.80 cc/g.
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) | 1993-04-09 | 1993-10-09 | 1994-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-09 | 1997-10-09 | 1998-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-09 | 2001-10-09 | 2002-04-10 | $7700.00 | Window Closed / Lapsed |