Classifications

• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
  • G03G9/00—Developers
  • G03G9/08—Developers with toner particles
  • G03G9/093—Encapsulated toner particles
  • G03G9/09307—Encapsulated toner particles specified by the shell material
  • G03G9/09314—Macromolecular compounds
  • G03G9/09321—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
  • B01J13/02—Making microcapsules or microballoons
  • B01J13/025—Applications of microcapsules not provided for in other subclasses
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
  • B01J13/02—Making microcapsules or microballoons
  • B01J13/06—Making microcapsules or microballoons by phase separation
  • B01J13/12—Making microcapsules or microballoons by phase separation removing solvent from the wall-forming material solution
  • B01J13/125—Making microcapsules or microballoons by phase separation removing solvent from the wall-forming material solution by evaporation of the solvent
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
  • G03G9/00—Developers
  • G03G9/08—Developers with toner particles
  • G03G9/093—Encapsulated toner particles
  • G03G9/0935—Encapsulated toner particles specified by the core material
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
  • G03G9/00—Developers
  • G03G9/08—Developers with toner particles
  • G03G9/093—Encapsulated toner particles
  • G03G9/0935—Encapsulated toner particles specified by the core material
  • G03G9/09357—Macromolecular compounds
  • G03G9/09371—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds

Definitions

• an encapsulated electrostatographic toner material which can be pressure fixed would be desirable and advantageous since unencapsulated materials which undergo cold flow tend to form tacky images on the copy sheet which often offset to other adjacent sheets. Toner particles containing unencapsulated materials which undergo cold flow tend to bridge, cake and block during production and in the shipping container as Well as in the electrostatographic imaging machine. Also, the toner material should be capable of accepting a charge of the correct polarity such as when brought into rubbing contact with the surface of carrier materials in cascade, magnetic brush or touchdown development systems. Some toner materials which possess many properties which would be desirable in electrostatographic toners dispense poorly and cannot be used in automatic copying and duplicating machines. Other toners dispense well but form images which are characterized by low density, poor resolution, or high background. Further, some toners are unsuitable for processes were electrostatic transfer is employed.
• the toner may comprise a black pigment such as carbon black or a black dye such as Amaplast Black dye, available from National Aniline Products, Incorporated.
• a black pigment such as carbon black or a black dye such as Amaplast Black dye, available from National Aniline Products, Incorporated.
• the pigment is employed in an amount from about 3 percent to about 20 percent by weight based on the total weight of the colored toner because better images are obtained. If the colorant employed is a dye, substantially smaller quantities of colorant may be used.
• Stick point, blocking test, and examination of crushed particles with the scanning electron microscope all indicate that the shell is principally polystyrene and the core principally the reaction product of isopropylidenediphenoxypropanol and adipic acid and carbon black.
• About 1 part by weight of the encapsulated toner particles Were mixed with about 99.parts by weight of 250 micron glass carrier beads and substituted for the developer in the testing machine described in Example I. Under substantially identical test conditions, except that the prints made were pressure fixed Without the assistance of heat, the degree of fix obtained was found to be about 4.4 Taber Cycles at 300 p.l.i. of pressure and about 9.7 Taber Cycles at 500 p.l.i. of pressure.
• carbon black is dispersed in the solution by severe agitation.
• the final concentrations are about 1.2 percent polystyrene, about 1.8 percent reaction product of isopropylidenediphenoxypropanol and sebacic acid, about 0.2 percent carbon black, and about 96.8 percent solvent.
• the solution, with dispersed carbon black is spray dried using a Bowen Engineering, Incorporated, five foot diameter spray dryer with a spinning disk atomizer operating at about 50,000 r.p.m. and a feed rate of about 200 ml./ minute. Drying air inlet temperature is about 136 F. and outlet air temperature is about 107 F.
• the dry product is a powder of about 7.9 micron diameter volume average particle size with a geometric standard deviation of about 1.75.
• Electron and/ or optical microscope examination shows the individual particles to be primarily spherical and to have a pigmented core surrounded by a substantially clear shell.
• Stick point, blocking tests and examination of crushed particles with the scanning electron microscope all indicate that the shell is principally polystyrene and the core principally the reaction product of isopropylidenediphenoxypropanol and sebacic acid and carbon black.
• About 1 part by weight of the encap sulated toner particles were mixed with about 99 parts by weight of 250 micron glass carrier beads and substituted for the developer in the testing machine described in Example I. Under substantially identical test conditions, except that the prints made were pressure fixed without the assistance of heat, the degree of fix obtained was about 6.0 Taber Cycles at 400 p.l.i.
• Example XVIII An encapsulated toner material is prepared from a solution comprising about 1600 grams of a polystyrene (PS2) and about 1600 grams of the reaction product of isopropylidenediphenoxypropanol and sebacic acid having a number average molecular weight of about 2230 in a mixture of chloroform and cyclohexane at a 1:3 chloroformzcyclohexane volume ratio.
• a carbon black is dispersed in the solution by severe agitation.
• the final concentrations are about 4.75 percent polystyrene, about 4.75 percent reaction product of isopropylidenediphenoxypropanol and sebacic acid, about 0.5 percent carbon black, and about 90.0 percent solvent.

Landscapes

• Chemical & Material Sciences (AREA)
• Physics & Mathematics (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Organic Chemistry (AREA)
• General Physics & Mathematics (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Dispersion Chemistry (AREA)
• Developing Agents For Electrophotography (AREA)
• Manufacturing Of Micro-Capsules (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=22798846

Family Applications (1)

Country Status (12)

Cited By (28)

Families Citing this family (18)

• 0
  • BE BE793247D patent/BE793247A/xx unknown
• 1971
  • 1971-12-30 US US00214374A patent/US3788994A/en not_active Expired - Lifetime
• 1972
  • 1972-11-07 CA CA155,822A patent/CA985943A/en not_active Expired
  • 1972-11-13 JP JP11374572A patent/JPS548104B2/ja not_active Expired
  • 1972-11-14 AR AR245122A patent/AR200575A1/es active
  • 1972-12-07 BR BR8648/72A patent/BR7208648D0/pt unknown
  • 1972-12-13 FR FR7244381A patent/FR2167021A5/fr not_active Expired
  • 1972-12-18 DE DE2261969A patent/DE2261969C3/de not_active Expired
  • 1972-12-19 GB GB5856872A patent/GB1406687A/en not_active Expired
  • 1972-12-28 NL NL7217770A patent/NL7217770A/xx not_active Application Discontinuation
  • 1972-12-29 IT IT34021/72A patent/IT973323B/it active
  • 1972-12-29 ES ES410212A patent/ES410212A1/es not_active Expired

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