Patent US4450461A successfully refreshed from Google Patents.
Patent US4636451A successfully refreshed from Google Patents.
US4636451A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure-fixable toner material and method of making same
Assignee: 3M Co
•
Filing: 1986-02-13
•
Granted: 1987-01-13
•
Expires: 2006-02-13
Abstract
Abstract Pressure-fixable toner particles suitable for use in electrostatic copying machines and method of preparing same. The toner particle is spherical in shape and comprises a thin, substantially continuous surface layer of polyurea, and an interior portion comprising a matrix of polyurea, said matrix having a colorant and pressure-fixable material contained therein, said polyurea matrix forming a continium extending from the surface layer inwardly toward the center of said particle. The method comprises: (1) admixing colorant, pressure-fixable material, isocyanate, and matrix-forming co-reactant to form a mixture, (2) emulsifying said mixture in an aqueous medium containing a non-reactive emulsifying agent to provide a dispersion of spheres of the mixture, (3) hydrolyzing a first portion of the isocyanate near the surface of the spheres to initiate formation of polyurea at the surface of the spheres as a thin, substantially continuous layer and in the interior of the spheres as a continuum for some distance beneath the surfaces of said spheres, and reacting a second portion of the isocyanate with said matrix-forming co-reactant to form additional matrix material in the interiors of the spheres, (4) removing the emulsifying agent from the dispersion, and (5) removing water from the dispersion to obtain dry spherical toner particles.
Inventors
- 👤 Josef Matkin
- 👤 Richard J. Treleaven
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 12:28
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/0827; G03G9/087; G03G9/08742; G03G9/08764; G03G9/093; G03G9/09307; G03G9/09314; G03G9/09328; G03G9/0935; G03G9/09357; G03G9/09371; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/104
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
160 words
Method of preparing spherical toner particles comprising: (1) admixing a colorant, a pressure-fixable material, an isocyanate, and a matrix-forming co-reactant to form a mixture, (2) emulsifying said mixture in an aqueous medium containing a non-reactive emulsifying agent to provide a dispersion of spheres of said mixture, (3) hydrolyzing a first portion of the isocyanate near the surface of said spheres by contact with water in the aqueous medium to initiate formation of polyurea (a) at the surface of said spheres as a thin, substantially continuous layer and (b) in the interiors of said spheres as a continuum for some distance beneath the surfaces of said spheres, said continuum being a polyurea matrix, and reacting a second portion of the isocyanate within said spheres with said matrix-forming co-reactant to form additional matrix material in the interiors of said spheres, (4) removing said emulsifying agent from the dispersion, and (5) removing the water from the dispersion to obtain dry, spherical toner particles.
Claim 2
Dependent Claim
160 words
Method of preparing spherical toner particles comprising: (1) admixing a colorant, a pressure-fixable material, an isocyanate, and a matrix-forming co-reactant to form a mixture, (2) emulsifying said mixture in an aqueous medium containing a non-reactive emulsifying agent to provide a dispersion of spheres of said mixture, (3) hydrolyzing a first portion of the isocyanate near the surface of said spheres by contact with water in the aqueous medium to initiate formation of polyurea (a) at the surface of said spheres as a thin, substantially continuous layer and (b) in the interiors of said spheres as a continuum for some distance beneath the surfaces of said spheres, said continuum being a polyurea matrix, and reacting a second portion of the isocyanate within said spheres with said matrix-forming co-reactant to form additional matrix material in the interiors of said spheres, (4) removing said emulsifying agent from the dispersion, and (5) removing the water from the dispersion to obtain dry, spherical toner particles.
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein a charge control agent is introduced into the dispersion prior to the completion of the hydrolysis of the isocyanate.
Claim 4
Dependent Claim
15 words
The method of claim 2 wherein said charge control agent is an organic fluorochemical compound.
Claim 5
Dependent Claim
23 words
The method of claim 1 wherein a charge control agent is introduced into the dispersion after the emulsifying agent has been removed therefrom.
Claim 6
Dependent Claim
15 words
The method of claim 4 wherein said charge control agent is an organic fluorochemical compound.
Claim 7
Dependent Claim
16 words
The method of claim 1 wherein said emulsifying agent is removed from the dispersion by washing.
Claim 8
Dependent Claim
36 words
The method of claim 1 wherein the mixture in step 1 comprises from about 5% by weight to about 20% by weight matrix-forming co-reactant based on the combined weight of colorant, pressure-fixable material, and matrix-forming co-reactant.
Claim 9
Dependent Claim
22 words
The method of claim 1 wherein said matrix-forming co-reactant is selected from the group consisting of vegetable oils and synthetic drying oils.
Claim 10
Dependent Claim
22 words
The method of claim 1 wherein said isocyanate is selected from the group consisting of aromatic polyfunctional isocyanates and aliphatic polyfunctional isocyanates.
Claim 11
Dependent Claim
59 words
A spherical toner particle comprising a thin, substantially continuous surface layer of polyurea, surrounding an interior portion comprising a matrix comprising polyurea, said matrix having a colorant and pressure-fixable material contained therein, thereby providing discontinuities in said matrix, wherein said polyurea matrix forms a continuum extending inwardly from said continuous polyurea surface layer into the interior of said particle.
Claim 12
Dependent Claim
59 words
A spherical toner particle comprising a thin, substantially continuous surface layer of polyurea, surrounding an interior portion comprising a matrix comprising polyurea, said matrix having a colorant and pressure-fixable material contained therein, thereby providing discontinuities in said matrix, wherein said polyurea matrix forms a continuum extending inwardly from said continuous polyurea surface layer into the interior of said particle.
Claim 13
Dependent Claim
19 words
The toner particle of claim 10 wherein the colorant is selected from the group consisting of dyes and pigments.
Claim 14
Dependent Claim
33 words
The toner particle of claim 10 wherein said pressure-fixable material is selected from the group consisting of resins, polymers, and waxes having a melting point from about 50° C. to about 100° C.
Claim 15
Dependent Claim
15 words
The toner particle of claim 10 wherein said matrix further comprises a second urea-containing polymer.
Claim 16
Dependent Claim
15 words
The toner particle of claim 13 wherein said second urea-containing polymer is an acylurea polymer.
Claim 17
Dependent Claim
17 words
The toner particle of claim 10 wherein said particle further comprises a charge control agent adsorbed thereon.
Claim 18
Dependent Claim
16 words
The toner particle of claim 15 wherein said charge control agent is an organic fluorochemical compound.
Claim 19
Dependent Claim
17 words
The toner particle of claim 10 wherein said particle further comprises a charge control agent bonded thereto.
Claim 20
Dependent Claim
16 words
The toner particle of claim 17 wherein said charge control agent is an organic fluorochemical compound.
Claim 21
Dependent Claim
19 words
The toner particle of claim 10 wherein the diameter thereof can be from about 1 to about 40 micrometers.
References Cited (Backward Citations)
US3383316A
Cited
US3720534A
Cited
US3804764A
Cited
US3925219A
Cited
US4254201A
Cited
US4206064A
Cited
EP0002119A1
Cited
US4307169A
Cited
US4415645A
Cited
US4311779A
Cited
US4362803A
Cited
US4379825A
Cited
US4439510A
Cited
US4447516A
Cited
US4450221A
Cited
US4442194A
Cited
US4468446A
Cited
US4465755A
Cited
US4465756A
Cited
US4455362A
Cited
US4476211A
Cited
US4476212A
Cited
EP0088566A2
Cited
EP0103967A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-01-12 | 1990-07-14 | 1991-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-12 | 1994-07-14 | 1995-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-12 | 1998-07-14 | 1999-01-13 | $7700.00 | Window Closed / Lapsed |