Patent US4529680A successfully refreshed from Google Patents.
US4529680A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic toner for pressure fixation
Assignee: Mitsui Chemicals Inc
•
Filing: 1983-12-21
•
Granted: 1985-07-16
•
Expires: 2003-12-21
Abstract
Abstract A magnetic toner for pressure fixation containing at least a resin and a magnetic powder as the main components, where the resin is a polymer essentially, containing methyl-1-pentene as the main component and having a softening point of at least 80 DEG C. and a compression yield strength of not more than 150 kg/cm2, has a good fixability under a low pressure and a good preservability at a high temperature.
Inventors
- 👤 Masumi Asanae
- 👤 Koji Noguchi
- 👤 Hideyuki Itoi
- 👤 Katsumi Funakoshi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 16:34
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/087; G03G9/08702; G03G9/08704; G03G9/08735; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/104
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
77 words
A magnetic toner having a saturation magnetization of 50-65 emu/q for pressure fixation, which comprises a resin and a magnetic powder having an average particle size of 0.1-3 μm, the resin being a polymer, at least 70% by weight of said polymer being methyl-1-pentene, said polymer being the only polymer component in said toner, said polymer having a softening point of 80° C.-160° C. and a compression yield strength of not more than 150 kg/cm 2 .
Claim 2
Dependent Claim
77 words
A magnetic toner having a saturation magnetization of 50-65 emu/q for pressure fixation, which comprises a resin and a magnetic powder having an average particle size of 0.1-3 μm, the resin being a polymer, at least 70% by weight of said polymer being methyl-1-pentene, said polymer being the only polymer component in said toner, said polymer having a softening point of 80° C.-160° C. and a compression yield strength of not more than 150 kg/cm 2 .
Claim 3
Dependent Claim
22 words
A magnetic toner according to claim 1, wherein the polymer is a homopolymer of methyl-1-pentene or copolymers of methyl-1-pentene and other α-olefins.
Claim 4
Dependent Claim
18 words
A magnetic toner according to claim 2, wherein the methyl-1-pentene is 4-methyl-1-pentene, or 3-methyl-1-pentene, or a mixture thereof.
Claim 5
Dependent Claim
32 words
A magnetic toner according to claim 2, wherein the α-olefins are ethylene, propylene, 1-butene, isobutene, 1-pentene, 2-methyl-1-butene, 5-methyl-1-butene, 1-hexene, 3-methyl-1-hexene, 1-methyl-1-hexene, 1-heptene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, or 1-octadecene, or mixtures thereof.
Claim 6
Dependent Claim
24 words
A magnetic toner according to claim 2, wherein said polymer is a copolymer containing not more than 30% by weight of the other α-olefins.
Claim 7
Dependent Claim
25 words
A magnetic toner according to claim 1, wherein the polymer has an intrinsic viscosity [η] of 0.005-0.5 dl/g, and a melting point of 150°-240° C.
Claim 8
Dependent Claim
30 words
A magnetic toner according to claim 2, wherein the polymer is prepared by polymerization of methyl-1-pentene or by copolymerization of methyl-1-pentene and α-olefin in the presence of a stereospecific catalyst.
Claim 9
Dependent Claim
38 words
A magnetic toner according to claim 2, wherein the polymer is prepared by degradation of a polymer which is produced by polymerization of methyl-1-pentene or by copolymerization of methyl-1-pentene and α-olefin in the presence of a stereospecific catalyst.
Claim 10
Dependent Claim
16 words
A magnetic toner according to claim 8, wherein the degradation is carried out radically or thermally.
Claim 11
Dependent Claim
24 words
A magnetic toner according to claim 1, wherein the softening point is 90°-160° C., and the compression yield strength is 30-120 kg/cm 2 .
Claim 12
Dependent Claim
15 words
A magnetic toner according to claim 1, wherein the magnetic powder is a ferromagnetic material.
Claim 13
Dependent Claim
23 words
A magnetic toner according to claim 11, wherein the ferromagnetic material is iron, nickel, chromium, cobalt or their alloys, ferrite, hematite or magnetite.
Claim 14
Dependent Claim
19 words
A magnetic toner according to claim 12, wherein the ferromagnetic material is magnetite having an IHC of 80-400 Oe.
Claim 15
Dependent Claim
33 words
A magnetic toner according to claim 1, wherein said toner also includes at least one additive which functions as a color-controlling pigment, a charge-controlling agent, a resistance-controlling agent, or a dry lubricating powder.
Claim 16
Dependent Claim
26 words
A magnetic toner according to claim 14, wherein said additive or additives comprise not more than 10% by weight of the total weight of the toner.
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) | 1988-07-15 | 1989-01-14 | 1989-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-15 | 1993-01-14 | 1993-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-15 | 1997-01-14 | 1997-07-16 | $7700.00 | Window Closed / Lapsed |