US3669885A - Electrically insulating carrier particles - Google Patents
Electrically insulating carrier particles Download PDFInfo
- Publication number
- US3669885A US3669885A US8416A US3669885DA US3669885A US 3669885 A US3669885 A US 3669885A US 8416 A US8416 A US 8416A US 3669885D A US3669885D A US 3669885DA US 3669885 A US3669885 A US 3669885A
- Authority
- US
- United States
- Prior art keywords
- particles
- core
- glow discharge
- toner
- carrier vehicle
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
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- 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
- G03G9/10—Developers with toner particles characterised by carrier particles
- G03G9/113—Developers with toner particles characterised by carrier particles having coatings applied thereto
- G03G9/1132—Macromolecular components of coatings
- G03G9/1133—Macromolecular components of coatings obtained by reactions only involving carbon-to-carbon unsaturated bonds
-
- 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
- G03G9/10—Developers with toner particles characterised by carrier particles
- G03G9/113—Developers with toner particles characterised by carrier particles having coatings applied thereto
- G03G9/1131—Coating methods; Structure of coatings
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- 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
- G03G9/10—Developers with toner particles characterised by carrier particles
- G03G9/113—Developers with toner particles characterised by carrier particles having coatings applied thereto
- G03G9/1132—Macromolecular components of coatings
- G03G9/1133—Macromolecular components of coatings obtained by reactions only involving carbon-to-carbon unsaturated bonds
- G03G9/1134—Macromolecular components of coatings obtained by reactions only involving carbon-to-carbon unsaturated bonds containing fluorine atoms
Definitions
- Electrophotographic imaging processes and techniques have been extensively described in both the patent and other literature, for example, US. Pat. Nos. 2,221,776; 2,277,013; 2,297,691; 2,357,809; 2,551,582; 2,825,814; 2,833,658; 3,220,324; 3,220,831; 3,220,833 and many others.
- these processes have in common the steps of employing a normally insulating photoconductive element which is prepared to respond to imagewise exposure with electromagnetic radiation by forming an electrostatic charge image.
- the electrostatic latent image is then rendered visible by a development step in which the charged surface of the photoconductive element is brought into contact with a suitable developer mix.
- One method for applying the developer mix is by the wellknown magnetic brush process.
- Such a process generally utilizes apparatus of the type described, for example, in U.S. Pat. No. 3,003,462 and customarily comprises a nonmagnetic rotatably mounted cylinder having fixed magnetic means mounted inside.
- the cylinder is arranged to rotate so that part of the surface is immersed in or otherwise contacted with a supply of developer mix.
- the granular mass comprising the developer mix is magnetically attracted to the surface of the cylinder.
- the particles thereof arrange themselves in bristle-like formations resembling a brush.
- the bristle formations of developer mix tend to conform to the lines of magnetic flux, standing erect in the vicinity of the poles and lying substantially flat when said mix is outside the environment of the magnetic poles.
- the continually rotating tube picks up developer mix from a supply source and returns part or all of this material to the supply. This mode of operation assures that fresh mix is always available to the surface of the photoconductive element at its point of contact with the brush.
- the roller performs the successive steps of developer mix pickup, brush formation, brush contact with the photoconductive element, brush collapse and finally mix release.
- the developer is commonly a triboelectric mixture of fine toner powder comprised of dyed or pigmented thermoplastic resin with coarser carrier particles of a soft magnetic material such as ground chemical iron (iron filings), reduced iron oxide particles, or the like.
- the relatively high conductivity of iron and similar ferromagnetic carrier particles can be useful in magnetic brush development in that a conducting magnetic brush serves effectively as a development electrode, and as a consequence, the fringing field created by an electrostatic latent image is modified and solid area development is achieved.
- solid area development by such a means has the disadvantage of very narrow exposure latitude and hence conducting carriers are to be avoided if one desires to take advantage of fringing field effects to increase exposure latitude. Accordingly, there is a need for a magnetic brush developing composition which is capable of producing good images within a wide range of exposure latitude.
- Resinous coatings on iron or other magnetic brush carrier granules can increase the surface resistance and the tendency toward fringing development.
- application of a coating of insulating resin of sufficient minimum thickness to effect the required reduction in surface conductivity is a difficult operation.
- the plastic whether applied from a melt, a hydrosol, or a dope, tends to solidify to a compact mass with the carrier particles, so that it is difficult to recover the coated iron in the desired form of discrete uniformly coated bits. Grinding or other forms of comminution of such a compacted or agglomerated mass of particles will usually result in exposing a sufficient amount of the conducting surface of the underlying particles to largely negate the intended improvement in resistance.
- prior coating procedures involve multi-step processes which make it difficult to control the thickness of the material deposited on the underlying core and which generally do not result in a continuous film being formed on each individual particle.
- a further problem with prior coating techniques is that the outer layer of coated material is generally subject to wear during usage which results in a variation in the physical properties with time.
- An additional object of this invention is to provide novel carrier particles which have an outer polymeric coating which is resistant to wear.
- Still another object of the invention is to provide new developer compositions suitable for use in fringing development of electrostatic latent images.
- carrier particles having a relatively high electrical resistance.
- These particles are each comprised of a core material of appropriate size and shape over which is coated athin, continuous layer of electrically insulating resinous material.
- the core materials which can suitably be overcoated in accordance with this invention include a variety of materials such as magnetic and nonmagnetic materials.
- Typical nonmagnetic materials include, for example, glass beads or crystals or organic salts such as sodium or potassium chloride.
- the present invention is particularly well suited for use with cores of magnetic materials.
- the phrase "magnetic materials" as used herein encompasses a variety of magnetically attractable materials. Particularly useful materials wouldinclude ferromagnetic materials such as metals of the first transition series, i.e., nickel, iron, cobalt, and alloys containing any or all of these metals. Other useful materials which exhibit a net magnetic moment are the ferrimagnetic materials.
- ferrimagnetic materials examples include the ferrites, which are materials having the general formula Meo-Fe O where Me is a metal ion, as well as the mixed ferrites, which contain more than one species of metal ion in addition to iron, and the substituted ferrites, in which another metal replaces some of the iron.
- magnetic material particles such as those described in copending Miller U. S. application Ser. No. 562,497, filed July 5, 1966, now abandoned, entitled ELECTROPHOTOGRAPHIC DEVELOPING COMPOSITIONS, and which are comprised of, for example, iron dispersed in a resin binder.
- Such magnetic materials are used as a core in accordance with this invention over which is coated a film-forming resinous material.
- the core can consist of a solid particle of magnetic material or can be a nonmagnetic particle overcoated with ferromagnetic materials as described in copending Miller U. S. application Ser. No. 699,030, filed Jan. 19, 1968, now abandoned, entitled METAL SHELL CARRIER PARTICLES.
- the core material used can vary in size and shape, with core materials having an average diameter of from about 1,200 to about 30 microns being useful. Particularly useful results are obtained with core materials of from about 600 to about 40 microns average diameter.
- the size of the core particles used will, of course, be
- average diameter is not meant to imply that only perfectly uniformly dimensioned particles can be used. This phrase is used to refer to the average thickness of particles when measured along several axes. Average diameter also refers to the approximate size of the openings in a standard sieve series which will just retain or just pass a given particle.
- the core particles are coated with a continuous film of resinous material.
- a thin layer of material is applied to the core particles by a procedure which we generally refer to as glow discharge polymerization.”
- glow discharge polymerization an organic vapor at about 0.5 to 5.0 mm. of mercury pressure is introduced into a chamber containing two parallel closely spaced electrodes.
- a.c. or d.c. fields of the order of several hundred v/crn. are imposed on the parallel electrodes, a uniform discharge forms between the plates and polymeric films are deposited on articles contained between the electrodes.
- this procedure involves introducing a concentration of a vaporous or gaseous monomer or other polymer precursor into a reaction chamber containing suitable core particles and subjecting the materials to activating electromagnetic radiation to cause the monomer or polymer precursor to undergo polymerization on the surface of the core particles. During this procedure, the particles are kept in motion by any suitable means.
- the apparatus involved in forming these thin polymer layers is quite simple, and is mainly comprised of a chamber which may be evacuated to a pressure of the order of about 0.1 to about 3 mm. of mercury. After evacuating the chamber, an unreactive gas such as helium is bled into the apparatus to increase the pressure to about 0.3 to 5 mm. of mercury.
- a means for containing and vibrating or otherwise thoroughly agitating the core particles to be coated is located within this chamber.
- One suitable means for this purpose is an aluminum plate which is maintained at ground potential and which is held in an insulating holder that is capable of being vibrated so as to maintain the particles in a relatively fluidized state.
- Located above the plate holding the particles is a large high potential electrode typically prepared of stainless steel. This electrode is maintained in close proximity to the particles, usually at a distance of about 1% to about 2% cm. depending on the potential applied, etc.
- This electrode is connected to a power source capable of maintaining at least a kilocycle a.c. field sufficient to produce an even glow.
- glow discharge is typical of many suitable arrangements which can be used to activate the vaporized monomer.
- Other useful means of activation would include direct current, electrodeless radio frequency, microwave glow discharge, as well as ultraviolet radiation and electron bombardment.
- helium or other nonreactive gas Prior to forming a polymer coating on the core particles, it is often desirable to clean the particles. This can be done by introducing helium or other nonreactive gas into the system and subjecting the particles to glow discharge treatment. The helium is bled off and then the vaporized monomer or polymer precursor is introduced into the chamber at a pressure of 0.5 to 5 mm. of mercury and once again subjected to a glow discharge.
- the vaporizable monomer or polymer precursors which are useful can be selected from a wide variety of materials.
- Suitable materials would include such monomers as trifluoromonochloroethylene, hexafluoropropylene, tetrafluoroethylene, octafluorobutene-Z, vinyl fluoride, vinylidene fluoride, hexafluoroacetone, acrylonitrile, styrene, ethylene, vinyl chloride, vinyl ferrocene, methyl methacrylate, divinylbenzene, carbon tetrachloride, hexafluoroethane, etc, as well as materials which are not generally considered as polymer precursors such as benzene, naphthalene and anthracene.
- any vaporizable vinyl monomer is suitable for use herein.
- mixtures of these or any other vaporizable polymer precursors which undergo polymerization in the presence of activating radiation can be used.
- extremely thin, continuous layers of electrically insulating materials can be applied to various core materials.
- the amount of resin applied is usually in the range of from about 0.003 to about 4 percent by weight of the core material being coated with preferred materials having a resin coating of from about 0.03 to about 0.2 percent by weight of the core.
- the average thickness of the continuous film of polymer applied in accordance with this technique is in the range of from about 0.005 to about 4.0 microns, with a thickness of about 0.05 to about 0.2 microns being preferred.
- the electrical resistance of the coated carrier particles of this invention is greater than about 10' ohms with preferred carriers having a resistance of greater than about 10 ohms.
- the higher the resistance of the carrier particle the better the quality of the fringe development obtained.
- the increase in quality of fringe develop ment per unit increase of resistance becomes so small as to be negligible.
- the resistance of various magnetically attractable carrier particles is measured in a standard magnetic brush resistance test. This test is conducted each time using a 15 gram quantity of the carrier particles. A cylindrically shaped bar magnet having a circular end of about 6.25 cm. in area is used to attract the carrier and hold it in the form of a brush. After formation of the brush, the bar magnet is then positioned with the brush-carrying end approximately parallel to and about 0.5 cm. from a burnished copper plate. The resistance of the particles in the magnetic brush is then measured between the magnet and the copper plate.
- the resin layers formed on the carrier particles of the present invention are extremely durable and abrasion resistant.
- the improved abrasion resistance of the present polymer coatings appears to be a result of the considerable crosslinking which occurs during the discharge polymerization reaction used to coat the core materials.
- Electroscopic developer compositions can be prepared by mixing from about to about 99 percent by weight of the present carrier particles with from about 10 to about 1 percent by weight of a suitable electroscopic toner material.
- the toner granules useful with the carrier are generally comprised of a resin binder and a colorant.
- Suitable toners can be selected from a wide variety of materials to give desired physical properties to the developed image and the proper triboelectric relationship to match the carrier particles used.
- any of the toner powders known in the art are suitable for mixing with the carrier particles of this invention to form a developer composition.
- the toner powder selected is utilized with ferromagnetic carrier particles in a magnetic brush development arrangement, the toner clings to the carrier by triboelectric attraction.
- the carrier particles acquire a charge of one polarity and the toner acquires a charge of the opposite polarity.
- the toner normally acquires a positive charge and the carrier a negative charge.
- Useful toner granules can be prepared by various methods. Two convenient techniques for preparing these toners are spray-drying or melt-blending followed by grinding. Spraydrying involves dissolving the resin, colorant and any additives in a volatile organic solvent such as dichloromethane. This solution is then sprayed through an atomizing nozzle using a substantially nonreactive gas such as nitrogen as the atomizing agent. During atomization, the volatile solvent evaporates from the airborne droplets, producing toner particles of the uniformly colored resin. The ultimate particle size is determined by varying the size of the atomizing nozzle and the pressure of the gaseous atomizing agent. conventionally, particles of a diameter between about Vapand about 25p. are used, with particles between about 2p. and 15p, being preferred, although larger or smaller particles can be used where desired for particular development or image considerations.
- Suitable toners can also be prepared by melt-blending. This technique involves melting a powdered form of polymer or resin and mixing it suitable colorants and additives. The resin can readily be melted or heated on compounding rolls which are also useful to mix or otherwise blend the resin and addenda so as to promote the complete intermixing of these various ingredients. After thorough blending, the mixture is cooled and solidified. The resultant solid mass is then broken into small pieces and finely ground to form a free-flowing powder of toner granules. The resultant toner granules usually range in size from about 9% to about 25 1..
- the resin material used in preparing the toner can be selected from a wide variety of materials, including natural resins, modified natural resins and synthetic resins.
- useful natural resins are balsam resins, colophony, and shellac.
- suitable modified natural resins are colophony-modified phenol resins and other resins listed below with a large proportion of colophony.
- Suitable synthetic resins are all synthetic resins known to be useful for toner purposes, for example, polymers, such as vinyl polymers and copolymers including polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyvinyl acetals, polyvinyl ether, polyacrylic and polymethacrylic esters, polystyrene, including substituted polystyrenes; polycondensates, e.g., polyesters, such as phthalate, terephthali'c and isophthalic polyesters, maleinate resins and colophony-mixed esters of higher alcohols; phenol-formaldehyde resins, including modified phenol-fonnaldehyde condensates; aldehyde resins; ketone resins; polyamides; polyurethanes, etc.
- polymers such as vinyl polymers and copolymers including polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate
- chlorinated rubber and polyolefins such as various polyethylenes, polypropylenes, polyisobutylenes, are also suitable.
- Additional toner materials which are useful are disclosed in the following U.S. Pat. Nos: 2,917,460, Re 25,136; 2,788,288; 2,638,416; 2,618,552 and 2,659,670.
- the coloring material additives useful in suitable toners are preferably dyestuffs and colored pigments. These materials serve to color the toner and thus render it more visible. In addition, they sometimes affect, in a known manner the polarity of the toner. In principle, virtually all of the compounds mentioned in the Color Index, Vol. I and 11, Second Edition, 1956, can be used as colorants. Included among the vast number of suitable colorants would be such materials as Nigrosin Spirit soluble (CI. 50415), I-Iansa Yellow G (CI. 11680), Chromogen Black ETOO (CI. 14645), Rhodamine B (CI. 45170), Solvent Black 3 (C.I. 26150), Fuchsine N (CI. 42510), C.l. Basic Blue 9 (Q1. 52015), etc. i
- Nickel-plated spherical iron particles are prepared in accordance with the electroless plating technique of Example 2 of copending Miller application Ser. No. 799,967, filed Feb. 17, 1969, now abandoned, entitled HIGHLY CONDUCT'IVE CARRIER PARTICLES. These core particles have a size such that they will pass through an 80 mesh screen and be retained by a 120 mesh screen and they have a resistance of 5 ohms as measured in the standard resistance test.
- Four grams of the nickeLclad iron particles are placed in an aluminum plate at ground potential and spread around such that they are contained in an area approximately 4.3 cm. X 4.3 cm.
- the aluminum plate is mounted in an insulating plastic holder capable of being vibrated so as to maintain the particles in a fluidized state.
- a high potential electrode comprised of a 7% X 7% cm. stainless steel plate is mounted approximately 1 cm. above the aluminum plate.
- the apparatus is placed a vacuum chamberwhich is evacuated to apressure of about 0.8 mm. of mercury. Helium is then bled into the apparatus to increase the pressure to about 2.0 mm. of mercury.
- the core particles are cleaned by applying a 10 kc. a.c. field sufficient to produce a glow at a current of 90 rnilliamperes across the electrodes for 5 minutes.
- the electrical equipment used to produce this field is comprised of an audio oscillator, a 200 watt audio amplifier and a step up transformer.
- a 1,000 ohm current limiting resistor is placed in the lead to the high voltage electrode and the voltage drop across this resistor is recorded and used to calculate the current.
- the a.c. field is terminated and the chamber is evacuated again to about 0.8 mm. of mercury and gaseous tetrafluoroethylene is introduced into the chamber to increase the pressure to about 1.3 mm. of mercury.
- An electric field is again applied using a current of about 45 ma. for a period of IS minutes.
- the particles are continually agitated.
- the resulting particles are free-flowing and have a thin, continuous layer of polymerized tetrafluoroethylene thereon. No agglomeration of particles occurs.
- the particles have a resistance of greater than 10" ohms.
- the carrier particles as produced'above are mixed with 4 percent by weight of an electroscopic toner material comprised of a polystyrene resin containing carbon black.
- the resultant developer mixture is applied to a handheld magnet to form a magnetic brush.
- This magnetic brush is then used to develop an electrostatic latent image carried on an electrophotographic element comprising a conducting support having coated-thereon a photoconductive layer containing an organic photoconductor and a polycarbonate binder.
- the developed image is transferred electrostatically to a white bond paper receiving sheet and fixed with heat.
- the developer gives good fringing development and good image quality.
- EXAMPLE 2 Four grams of the nickel-clad iron particles of Example 1 are placed in the apparatus described in Example 1 and cleaned by exposure to glow discharge for 2 minutes using a current of ma. in a helium atmosphere at a pressure of about 1.5 mm. of mercury. The pressure is reduced to about 0.8 mm. of mercury and acrylonitrile vapor is bled into the apparatus until the pressure rises to about 1.5 mm. of mercury. The particles are vibrated continuously while subjected to glow discharge for 30 seconds with a current of from 50 to 60 ma. The resultant free flowing particles have a resistance as measured in the standard resistance test of about 5 X 10 ohms. The resultant carrier particles are mixed with 4 percent by weight of the toner material of Example 1 and used to develop an electrostatic image. A fringe developed image results which is of good quality.
- EXAMPLE 3 Four grams of nickel-plated spherical iron particles similar to those described in Example 1 and having a particle size such that they will pass through a 150 mesh screen and be retained by a 200 mesh screen are exposed to a glow in the apparatus described in Example 1.
- the glow discharge treatment is conducted in a helium atmosphere at a pressure of 1.5 mm. of mercury for 5 minutes at a current of 95 ma.
- the particles are removed from the glow discharge apparatus and measured in the standard resistance test and found to have a resistance of 150 ohms as compared to 5 ohms prior to the glow discharge treatment. This increase in resistance of about ohms indicates that apparently some surface oxidation occurs in the glow discharge treatment.
- the resultant material is used to form a developer mixture comprising 4 percent by weight of the toner of Example 1.
- the resultant developer mixture is used to develop an electrostatic image and is found to produce solid area development.
- the fringing development obtained in Examples 1 and 2 cannot be exlimited to iron particles in that the conductivity of the particles to be coated plays no part in the procedures of this invention. Consequently, the coating or encapsulation procedures of this invention can be used on any metallic or nonmetallic core particle.
- suitable coatings may be applied by any system capable of activating a vaporized monomer, and the term glow discharge treatment is meant to include, for example, direct current, alternating current, electrodeless radio frequency and microwave glow discharge, as well as ultraviolet treatment and electron bombardment.
- the materials for coating the core particles may include conventional monomers as well as vaporizable organic and inorganic molecules known to undergo glow discharge polymerization.
- the core particles are maintained in an agitated state during the cleaning and coatin g procedures. It is desirable that the particles are maintained in this agitated state so as to insure that each particle receives a continuous coat without causing agglomeration of a plurality of particles.
- the separation of particles in the above examples is accomplished by a vibratory motion, it is evident that other methods of keeping the particles apart are equally useful such as fluidization with a gas, mechanical stirring or cascading the particles through the polymerizable vapors, etc,
- a developer composition for use in developing electro static charge patterns comprising a mixture of electroscopic toner material and a particulate, free-flowing carrier vehicle, said carrier vehicle comprising individual particles each having a core having coated thereon a thin, continuous layer of a glow discharge polymerized material.
- a developer composition for use in developing electrostatic charge patterns comprising a mixture of electroscopic toner material and a particulate, free-flowing carrier vehicle for said toner material, said carrier vehicle comprising individual particles each having a core of a magnetically responsive material overcoated with a thin, continuous, film of an electrically insulating glow discharge polymerized material.
- a developer composition for use in developing electrostatic charge patterns comprising a mixture of electroscopic toner material and a particulate, free-flowing carrier vehicle for said toner, said carrier vehicle comprising individual particles each having a core of a magnetically responsive material overcoated with a thin, continuous, film of an electrically insulating glow discharge polymerized material, said core containing a material selected from the group consisting of iron, nickel, cobalt, and alloys thereof, said glow discharge polymerized material being formed from a gaseous polymerizable material selected from the group consisting of trifluoromonochloroethylene, hexafluoropropylene, tetrafluoroethylene, octafluorobutene-2, vinyl fluoride, vinylidene fluoride, hexafluoroacetone, acrylonitrile, styrene, ethylene, vinyl chloride, vinyl ferrocene, carbon tetrachloride, hexafluoroethane, methyl
- a developer composition as described in claim 3 wherein said film on said core is formed of a glow discharge polymerized monomer selected from the group consisting of tetrafluoroethylene, acrylonitrile, and vinylidene fluoride.
- a developer composition as described in claim 3 wherein said toner material comprises from about I to about K) percent by weight of said composition.
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Developing Agents For Electrophotography (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US841670A | 1970-02-03 | 1970-02-03 |
Publications (1)
Publication Number | Publication Date |
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US3669885A true US3669885A (en) | 1972-06-13 |
Family
ID=21731476
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US8416A Expired - Lifetime US3669885A (en) | 1970-02-03 | 1970-02-03 | Electrically insulating carrier particles |
Country Status (6)
Country | Link |
---|---|
US (1) | US3669885A (ru) |
AU (1) | AU2489471A (ru) |
BE (1) | BE762324A (ru) |
CA (1) | CA936401A (ru) |
FR (1) | FR2080485A5 (ru) |
GB (1) | GB1342748A (ru) |
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3898170A (en) * | 1972-03-21 | 1975-08-05 | Eastman Kodak Co | Electrographic carrier vehicle and developer composition |
US3898171A (en) * | 1973-12-03 | 1975-08-05 | Addressograph Multigraph | Electroscopic powder with sharp melting point containing sucrose benzoate and a thermoplastic resin |
US3916038A (en) * | 1972-02-24 | 1975-10-28 | Lion Fat Oil Co Ltd | Process of producing moldable magnetic powder of the ferrite type |
US3935340A (en) * | 1972-12-04 | 1976-01-27 | Lion Yushi Kabushiki Kaisha | Process for preparing plastic coated metal powders |
US3945823A (en) * | 1972-11-21 | 1976-03-23 | Xerox Corporation | Electrostatographic reversal development with developer comprising poly(p-xylene)-coated carrier particles |
US3965022A (en) * | 1973-06-29 | 1976-06-22 | Minnesota Mining And Manufacturing Company | Pressure-fixable developing powder |
US4042517A (en) * | 1972-12-18 | 1977-08-16 | Xerox Corporation | Electrostatographic developer mixture containing a thermoset acrylic resin coated carrier |
US4206065A (en) * | 1978-10-30 | 1980-06-03 | Xerox Corporation | Electrostatographic developer compositions using terpolymer coated carrier |
US4374180A (en) * | 1979-09-25 | 1983-02-15 | Gorelik R A | Method for modification of the surface of industrial rubber articles |
US4464417A (en) * | 1983-02-02 | 1984-08-07 | The United States Of America As Represented By The Department Of Energy | Method for minimizing contaminant particle effects in gas-insulated electrical apparatus |
US4822708A (en) * | 1986-08-01 | 1989-04-18 | Minolta Camera Kabushiki Kaisha | Carrier for use in developing device of electrostatic latent image and production thereof |
US4822709A (en) * | 1986-07-10 | 1989-04-18 | Minolta Camera Kabushiki Kaisha | Binder-type carrier suitable for a developing method of electrostatic latent images |
US4824753A (en) * | 1986-04-30 | 1989-04-25 | Minolta Camera Kabushiki Kaisha | Carrier coated with plasma-polymerized film and apparatus for preparing same |
US4847176A (en) * | 1986-07-10 | 1989-07-11 | Minolta Camera Kabushiki Kaisha | Binder-type carrier |
US4861693A (en) * | 1987-02-20 | 1989-08-29 | Minolta Camera Kabushiki Kaisha | Carrier for electrophotography |
US4868082A (en) * | 1987-01-29 | 1989-09-19 | Minolta Camera Kabushiki Kaisha | Binder type carrier |
US4950574A (en) * | 1984-02-06 | 1990-08-21 | Hitachi Chemical Company, Ltd. | Toner for developing electrostatic image comprising vinyl polymer having hydroxyl number of 50 to 350 |
US4971880A (en) * | 1988-06-07 | 1990-11-20 | Minolta Camera Kabushiki Kaisha | Developer containing halogenated amorphous carbon particles prepared by plasma-polymerization |
US6070317A (en) * | 1996-05-08 | 2000-06-06 | Espey Mfg. & Electronics Corp. | Quiet magnetic structures |
US20040151617A1 (en) * | 2003-01-31 | 2004-08-05 | Zanakis Michael F. | Methods and apparatus for air sterilization |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CA1003262A (en) * | 1972-11-21 | 1977-01-11 | Xerox Corporation | Developer material |
FR2379889A1 (fr) * | 1977-02-08 | 1978-09-01 | Thomson Csf | Dielectrique constitue par un polymere en couche mince, procede de fabrication de ladite couche, et condensateurs electriques comportant un tel dielectrique |
US5141834A (en) * | 1988-10-03 | 1992-08-25 | Daikin Industries, Ltd. | Carriers for developing electrostatic images |
GB9102768D0 (en) * | 1991-02-09 | 1991-03-27 | Tioxide Group Services Ltd | Coating process |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3247014A (en) * | 1963-05-29 | 1966-04-19 | Battelle Development Corp | Method of coating solid particles |
US3326177A (en) * | 1963-09-12 | 1967-06-20 | Pennsalt Chemicals Corp | Metal vapor coating apparatus |
US3387991A (en) * | 1964-10-13 | 1968-06-11 | Rexall Drug Chemical | Glow discharge polymerization coating of polyolefin surfaces to render them receptive to adhesives, inks, and the like |
US3392139A (en) * | 1965-05-03 | 1968-07-09 | Monsanto Graphic Syst | Electroscopic powder containing titania-calcium sulfate pigment |
US3440085A (en) * | 1963-12-16 | 1969-04-22 | Nuclear Materials & Equipment | Method of and apparatus for producing coated particles |
US3447950A (en) * | 1966-02-03 | 1969-06-03 | Valley Metallurg Processing | Production of encapsulated powders |
US3461092A (en) * | 1965-08-23 | 1969-08-12 | Owens Illinois Inc | Solid particulate printing ink composition and process for producing same |
US3466191A (en) * | 1966-11-07 | 1969-09-09 | Us Army | Method of vacuum deposition of piezoelectric films of cadmium sulfide |
US3507686A (en) * | 1967-06-23 | 1970-04-21 | Xerox Corp | Method of coating carrier beads |
US3526533A (en) * | 1966-08-10 | 1970-09-01 | Xerox Corp | Coated carrier particles |
US3533829A (en) * | 1965-12-14 | 1970-10-13 | Azote & Prod Chim | Process and apparatus for solidifying and granulating a paste |
-
1970
- 1970-02-03 US US8416A patent/US3669885A/en not_active Expired - Lifetime
-
1971
- 1971-01-08 CA CA102252A patent/CA936401A/en not_active Expired
- 1971-01-29 FR FR7102940A patent/FR2080485A5/fr not_active Expired
- 1971-01-29 BE BE762324A patent/BE762324A/xx unknown
- 1971-02-02 AU AU24894/71A patent/AU2489471A/en not_active Expired
- 1971-04-19 GB GB2056271A patent/GB1342748A/en not_active Expired
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3247014A (en) * | 1963-05-29 | 1966-04-19 | Battelle Development Corp | Method of coating solid particles |
US3326177A (en) * | 1963-09-12 | 1967-06-20 | Pennsalt Chemicals Corp | Metal vapor coating apparatus |
US3440085A (en) * | 1963-12-16 | 1969-04-22 | Nuclear Materials & Equipment | Method of and apparatus for producing coated particles |
US3387991A (en) * | 1964-10-13 | 1968-06-11 | Rexall Drug Chemical | Glow discharge polymerization coating of polyolefin surfaces to render them receptive to adhesives, inks, and the like |
US3392139A (en) * | 1965-05-03 | 1968-07-09 | Monsanto Graphic Syst | Electroscopic powder containing titania-calcium sulfate pigment |
US3461092A (en) * | 1965-08-23 | 1969-08-12 | Owens Illinois Inc | Solid particulate printing ink composition and process for producing same |
US3533829A (en) * | 1965-12-14 | 1970-10-13 | Azote & Prod Chim | Process and apparatus for solidifying and granulating a paste |
US3447950A (en) * | 1966-02-03 | 1969-06-03 | Valley Metallurg Processing | Production of encapsulated powders |
US3526533A (en) * | 1966-08-10 | 1970-09-01 | Xerox Corp | Coated carrier particles |
US3466191A (en) * | 1966-11-07 | 1969-09-09 | Us Army | Method of vacuum deposition of piezoelectric films of cadmium sulfide |
US3507686A (en) * | 1967-06-23 | 1970-04-21 | Xerox Corp | Method of coating carrier beads |
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3916038A (en) * | 1972-02-24 | 1975-10-28 | Lion Fat Oil Co Ltd | Process of producing moldable magnetic powder of the ferrite type |
US3898170A (en) * | 1972-03-21 | 1975-08-05 | Eastman Kodak Co | Electrographic carrier vehicle and developer composition |
US3945823A (en) * | 1972-11-21 | 1976-03-23 | Xerox Corporation | Electrostatographic reversal development with developer comprising poly(p-xylene)-coated carrier particles |
US3935340A (en) * | 1972-12-04 | 1976-01-27 | Lion Yushi Kabushiki Kaisha | Process for preparing plastic coated metal powders |
US4042517A (en) * | 1972-12-18 | 1977-08-16 | Xerox Corporation | Electrostatographic developer mixture containing a thermoset acrylic resin coated carrier |
US3965022A (en) * | 1973-06-29 | 1976-06-22 | Minnesota Mining And Manufacturing Company | Pressure-fixable developing powder |
US3898171A (en) * | 1973-12-03 | 1975-08-05 | Addressograph Multigraph | Electroscopic powder with sharp melting point containing sucrose benzoate and a thermoplastic resin |
US4206065A (en) * | 1978-10-30 | 1980-06-03 | Xerox Corporation | Electrostatographic developer compositions using terpolymer coated carrier |
US4374180A (en) * | 1979-09-25 | 1983-02-15 | Gorelik R A | Method for modification of the surface of industrial rubber articles |
US4464417A (en) * | 1983-02-02 | 1984-08-07 | The United States Of America As Represented By The Department Of Energy | Method for minimizing contaminant particle effects in gas-insulated electrical apparatus |
US4950574A (en) * | 1984-02-06 | 1990-08-21 | Hitachi Chemical Company, Ltd. | Toner for developing electrostatic image comprising vinyl polymer having hydroxyl number of 50 to 350 |
US4824753A (en) * | 1986-04-30 | 1989-04-25 | Minolta Camera Kabushiki Kaisha | Carrier coated with plasma-polymerized film and apparatus for preparing same |
US4822709A (en) * | 1986-07-10 | 1989-04-18 | Minolta Camera Kabushiki Kaisha | Binder-type carrier suitable for a developing method of electrostatic latent images |
US4847176A (en) * | 1986-07-10 | 1989-07-11 | Minolta Camera Kabushiki Kaisha | Binder-type carrier |
US4822708A (en) * | 1986-08-01 | 1989-04-18 | Minolta Camera Kabushiki Kaisha | Carrier for use in developing device of electrostatic latent image and production thereof |
US4868082A (en) * | 1987-01-29 | 1989-09-19 | Minolta Camera Kabushiki Kaisha | Binder type carrier |
US4861693A (en) * | 1987-02-20 | 1989-08-29 | Minolta Camera Kabushiki Kaisha | Carrier for electrophotography |
US4971880A (en) * | 1988-06-07 | 1990-11-20 | Minolta Camera Kabushiki Kaisha | Developer containing halogenated amorphous carbon particles prepared by plasma-polymerization |
US6070317A (en) * | 1996-05-08 | 2000-06-06 | Espey Mfg. & Electronics Corp. | Quiet magnetic structures |
US20040151617A1 (en) * | 2003-01-31 | 2004-08-05 | Zanakis Michael F. | Methods and apparatus for air sterilization |
Also Published As
Publication number | Publication date |
---|---|
CA936401A (en) | 1973-11-06 |
AU2489471A (en) | 1972-08-03 |
GB1342748A (ru) | 1974-01-03 |
FR2080485A5 (ru) | 1971-11-12 |
BE762324A (fr) | 1971-07-01 |
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