US4879199A
Expired / Lapsed
US
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Process for preparing encapsulated color toner compositions
Assignee: Xerox Corp
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Filing: 1988-10-20
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Granted: 1989-11-07
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Expires: 2008-10-20
Abstract
Abstract Disclosed is an improved stable colored toner composition comprised of resin particles, colloidal silica additive particles, and colored pigment particles; and wherein each of the toners are encapsulated in a continuous shell from about 1 to about 30 percent by weight of a waxy substance with a molecular weight of from about 500 to about 20,000.
Inventors
- 👤 Robert J. Gruber
- 👤 Raymond A. Yourd, III
- 👤 Paul C. Julien
- 👤 John F. Knapp
- 👤 Steven B. Bolte
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:46
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/093; G03G9/09307; G03G9/09335; G03G9/09314; G03G9/09321
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
66 words
A process for preparing encapsulated toner particles which comprises blending together resin particles, colored pigment particles, and a waxy substance with a molecular weight of from about 500 to about 20,000, micronizing the resulting mixture to form toner sized particles, and permitting the waxy substance to form an encapsulating continuous shell on the surface of the toner particles by subjecting the formed particles to heat spheroidization.
Claim 2
Dependent Claim
66 words
A process for preparing encapsulated toner particles which comprises blending together resin particles, colored pigment particles, and a waxy substance with a molecular weight of from about 500 to about 20,000, micronizing the resulting mixture to form toner sized particles, and permitting the waxy substance to form an encapsulating continuous shell on the surface of the toner particles by subjecting the formed particles to heat spheroidization.
Claim 3
Dependent Claim
24 words
A process according to claim 1 wherein the resin is selected from the group consisting of styrene acrylates, styrene methacrylates, and styrene butadiene polymers.
Claim 4
Dependent Claim
13 words
A process according to claim 2 wherein the styrene methacrylate is styrene/n-butyl methacrylate.
Claim 5
Dependent Claim
21 words
A process according to claim 1 wherein the pigment particles are selected from the group consisting of magenta, yellow, and cyan.
Claim 6
Dependent Claim
28 words
A process according to claim 1 wherein the pigment particles are present in an amount of from about 1 percent by weight to about 15 percent by weight.
Claim 7
Dependent Claim
19 words
A process according to claim 1 wherein the molecular weight of the waxy substance is less than about 6,000.
Claim 8
Dependent Claim
20 words
A process according to claim 1 wherein the waxy substance is selected form the group consisting of polyethylenes and polypropylenes.
Claim 9
Dependent Claim
18 words
A process according to claim 7 wherein the molecular weight of the polyethylene is less than about 6,000.
Claim 10
Dependent Claim
18 words
A process according to claim 7 wherein the molecular weight of the polypropylene is less than about 6,000.
Claim 11
Dependent Claim
23 words
A process according to claim 1 wherein the continuous shell is of a thickness of from about 0.25 micron to about 1.0 micron.
Claim 12
Dependent Claim
28 words
A process according to claim 1 wherein the waxy substance is present in an amount of from about 1 percent by weight to about 30 percent by weight.
Claim 13
Dependent Claim
24 words
A process according to claim 1 wherein colloidal silica additive particles are blended together with the resin particles, colored pigment particles, and waxy substance.
Claim 14
Dependent Claim
26 words
A process according to claim 1 wherein fatty acid metal salt additive particles are blended together with the resin particles, colored pigment particles, and waxy substance.
Claim 15
Dependent Claim
19 words
A process according to claim 1 wherein the heat spheroidization is effected at a temperature of about 600° F.
Claim 16
Dependent Claim
27 words
A process according to claim 1 wherein the heat spheroidization is effected by introducing the toner particles into a spray dryer by means of a powder feeder.
Claim 17
Dependent Claim
26 words
A process according to claim 1 wherein the toner particles are introduced into the spray dryer at a feed rate of about 10 grams per minute.
Claim 18
Dependent Claim
19 words
A process according to claim 1 wherein the resulting encapsulated toner particles are spherical in shape and free flowing.
Claim 19
Dependent Claim
82 words
A process for preparing an electrophotographic developer which comprises: a. preparing encapsulated toner particles by blending together resin particles, colored pigment particles, and a waxy substance with a molecular weight of from about 500 to about 20,000, micronizing the resulting mixture to form toner sized particles, and permitting the waxy substance to form an encapsulating continuous shell on the surface of the toner particles by subjecting the formed particles to heat spheroidization; and b. admixing the encapsulated toner particles with carrier particles.
Claim 20
Dependent Claim
82 words
A process for preparing an electrophotographic developer which comprises: a. preparing encapsulated toner particles by blending together resin particles, colored pigment particles, and a waxy substance with a molecular weight of from about 500 to about 20,000, micronizing the resulting mixture to form toner sized particles, and permitting the waxy substance to form an encapsulating continuous shell on the surface of the toner particles by subjecting the formed particles to heat spheroidization; and b. admixing the encapsulated toner particles with carrier particles.
Claim 21
Dependent Claim
43 words
A process according to claim 18 wherein the toner particles are present in an amount of about 1 part by weight and the carrier particles are present in an amount of from about 3 parts by weight to about 200 parts by weight.
Claim 22
Dependent Claim
18 words
A process according to claim 18 wherein the carrier particles comprise a steel core with a coating thereover.
Claim 23
Dependent Claim
13 words
A process according to claim 20 wherein the coating comprises a fluoropolymer resin.
Claim 24
Dependent Claim
27 words
A process according to claim 18 wherein the carrier particles comprise a ferrite core coated with a styrene, methylmethacrylate, triethoxy silane terpolymer coating containing carbon black particles.
Claim 25
Dependent Claim
25 words
A process according to claim 18 wherein the toner particles and carrier particles are admixed by blending in a roll mill for about 15 minutes.
Claim 26
Dependent Claim
28 words
A process according to claim 18 wherein the resulting developer exhibits a toner triboelectric product of from about negative or positive 30 to about negative or positive 90.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1992-11-06 | 1993-05-08 | 1993-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-11-06 | 1997-05-08 | 1997-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-11-06 | 2001-05-08 | 2001-11-07 | $7700.00 | Window Closed / Lapsed |