US4544604A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat-sensitive recording paper and filler therefor
Assignee: Mizusawa Industrial Chemicals Ltd
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Filing: 1985-01-03
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Granted: 1985-10-01
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Expires: 2005-01-03
Abstract
Abstract Disclosed is a filler for a heat-sensitive recording paper comprising finely divided amorphous silica having a BET specific surface area of 10 to 100 m 2 /g and a bulk density of 0.14 to 0.30 g/cc, said finely divided amorphous silica having such a secondary particle size distribution that secondary particles having a size smaller than 4 microns, as measured by the centrifugal precipitation method, occupy at least 90% by weight of the total particles. This filler is excellent in the effects of preventing the background coloration, improving the lubricating property, preventing the adhesion of scum and improving the image density.
Inventors
- 👤 Koichi Usui
- 👤 Masahide Ogawa
- 👤 Kunio Goto
- 👤 Teiji Sato
- 👤 Masanori Tanaka
- 👤 Seikichi Takahashi
- 👤 Kinichi Ono
- 👤 Seiji Kojima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:17
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/18; C01B33/187; C01B33/193; B; B41; B41M; B41M5/00; B41M5/26; B41M5/30; B41M5/337; B41M5/3377; C01P; C01P2002/00; C01P2002/02; C01P2004/00; C01P2004/51; C01P2004/60; C01P2004/61; C01P2004/62; C01P2006/00; C01P2006/11; C01P2006/12; C01P2006/19; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/254; Y10T428/259; Y10T428/29; Y10T428/2982; Y10T428/31504; Y10T428/31942
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
73 words
A filler for a heat-sensitive recording paper comprising finely divided amorphous silica having a BET specific surface area of 10 to 100 m 2 /g and a bulk density of 0.14 to 0.30 g/cc, said finely divided amorphous silica having such a secondary particle size distribution that secondary particles having a size smaller than 4 microns, as measured by the centrifugal precipitation method, occupy at least 90% by weight of the total particles.
Claim 2
Dependent Claim
73 words
A filler for a heat-sensitive recording paper comprising finely divided amorphous silica having a BET specific surface area of 10 to 100 m 2 /g and a bulk density of 0.14 to 0.30 g/cc, said finely divided amorphous silica having such a secondary particle size distribution that secondary particles having a size smaller than 4 microns, as measured by the centrifugal precipitation method, occupy at least 90% by weight of the total particles.
Claim 3
Dependent Claim
19 words
A filler as set forth in claim 1, wherein the amorphous silica is amorphous silica by the wet method.
Claim 4
Dependent Claim
29 words
A filler as set forth in claim 1, wherein the amorphous silica has a number average particle size of at least 30 millimicrons, as measured by an electron microscope.
Claim 5
Dependent Claim
22 words
A filler as set forth in claim 1, wherein the amorphous silica has an oil absorption of 100 to 200 cc/100 g.
Claim 6
Dependent Claim
23 words
A filler as set forth in claim 1, wherein the amorphous silica has a median secondary particle size of 0.2 to 1 micron.
Claim 7
Dependent Claim
52 words
A filler as set forth in claim 1, wherein the amorphous silica is one obtained by reacting an alkali metal silicate with an acid in a concentrated solution of a metal salt under such conditions that fine particles of a silica gel are directly precipitated without formation of a sol of silica.
Claim 8
Dependent Claim
136 words
A composite filler for a heat-sensitive recording paper, which comprises an amorphous silica filler having a BET specific surface area of 10 to 100 m 2 /g and a bulk density of 0.14 to 0.30 g/cc, which has such a secondary particle size distribution that secondary particles having a size smaller than 4 microns, as measured by the centrifugal precipitation method, occupy at least 70% by weight of the total particles, and an organic filler composed of fine particles of an amino resin obtained by condensing substantially equimolar amounts of a functional amino group-containing component and a formaldehyde component in the presence of a catalyst, which has an oil absorption of 20 to 90 ml/100 g and a specific surface area smaller than 20 m 2 /g at a weight ratio of from 90/10 to 10/90.
Claim 9
Dependent Claim
136 words
A composite filler for a heat-sensitive recording paper, which comprises an amorphous silica filler having a BET specific surface area of 10 to 100 m 2 /g and a bulk density of 0.14 to 0.30 g/cc, which has such a secondary particle size distribution that secondary particles having a size smaller than 4 microns, as measured by the centrifugal precipitation method, occupy at least 70% by weight of the total particles, and an organic filler composed of fine particles of an amino resin obtained by condensing substantially equimolar amounts of a functional amino group-containing component and a formaldehyde component in the presence of a catalyst, which has an oil absorption of 20 to 90 ml/100 g and a specific surface area smaller than 20 m 2 /g at a weight ratio of from 90/10 to 10/90.
Claim 10
Dependent Claim
44 words
A composite filler as set forth in claim 7, wherein the amino resin is urea-formaldehyde resin and has an X-ray diffraction pattern which is substantially the same as the following X-ray diffraction pattern: ______________________________________
d I/Io
______________________________________
4.05 100
3.70 40-70
2.90 5-20
______________________________________
References Cited (Backward Citations)
DE2800485A1
Cited
JPS54134650A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-30 | 1989-04-01 | 1989-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-30 | 1993-04-01 | 1993-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-30 | 1997-04-01 | 1997-10-01 | $7700.00 | Window Closed / Lapsed |