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Publication numberUS3854974 A
Publication typeGrant
Publication dateDec 17, 1974
Filing dateFeb 20, 1973
Priority dateAug 28, 1970
Also published asUS3932035
Publication numberUS 3854974 A, US 3854974A, US-A-3854974, US3854974 A, US3854974A
InventorsFukushima O, Sato M
Original AssigneeXerox Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Method for transferring a toner image
US 3854974 A
Abstract
A toner image is transferred from a toner substrate to a transfer sheet by bringing the toner substrate and the transfer sheet into face to face contact and applying a vibration thereto, while simultaneously applying pressure and/or an electrical field across the substrate and transfer sheet.
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Description  (OCR text may contain errors)

United States Patent 1 91 S Sato et al.

[ METHOD FOR TRANSFERRING A TONER IMAGE [75] Inventors: Masamichi Sato, Tucson, Ariz.;

Osamu Fukushima, Tokyo, Japan [73] Assignee: Xerox Corporation, Stamford,

Conn.

[22] Filed: Feb. 20, 1973 I [21] Appl. No.: 333,825

301 Foreign Application Priority Data Aug.28, 1970 Japan "45-75321 [52] US. Cl....;....., 117/17, 9 6/l.4, 117/17.5, 117/37 LE, 117/DIG. '8, 118/57, 118/637 {51] Int. Cl. G03g 13/16, G03g 15/16 [58] Field of Search l17/3.1, 16, 17, 17.5, 117/37 LE, DIG. 8; 96/1 R, 1.4; 118/637, 57;

[ Dec. 17, 1974 [56] References Cited UNITED STATES PATENTS 2,843,499 7/1958 Andrus 1l7/17.5 3,328,193 6/1967 Oliphant et al.... 118/637 3,399,111 '8/1968 Beaumont eta1.. 156/73 3,541,671 ll/l970 Frachot 156/73 3,653,948 4/1972 Kaernpgen et al. 118/57 3,658,519 4/1972 Men; 96/1.4 3,691,993 9/1972 Krause et al ll7/l7.5 3,698,314 10/1972 Grier...) 117/21 Primary E.raminer -Michael Sofocleous [57] ABSTRACT A toner image is transferred from a toner substrate to a transfer sheet by bringing the toner substrate and the transfer sheet into face to face contact and applying a vibration thereto, while simultaneously applying pressure and/or an electrical field across the substrate and transfer sheet.

9 Claims, 1 Drawing Figure METHOD FOR'TRANSFERRING A TONER IMAGE BACKGROUND AND SUMMARY OF Tl-IE INVENTION,

The present invention relates to a method and apparatus for transferring a toner image from a substrate to a receiving element such as a transfer sheet, and is particularly applicable to the transfer of atoner image obquency vibration thereto, while applying an electric field and/or pressure across the interface.

In the field of electric photography it is often necessary to transfer a toner image developed on one substrate to a transfer sheet. It is well known in the prior art to effect such transfer by employing such methods as electrostatic attraction, mechanical pressing and tacky adhesion. In the electrostatic method, a transfer sheet is brought into contact with atoner substrate and a corona discharge is applied to the rear surface of the transfer sheet to attract the toner thereto. In the me chanical-pressing method, a toner substrate is disposed on a transfer sheet and the "composite is conveyed through a pair of opposing pressure rollers, whereby the toner particles are caused to adhere to the transfer sheet. The tacky adhesion method is one in which a transfer sheet containing a tacky layer is pressed against the surface of the toner substrate, to transfer the 'toner image from'said substrate tothe transfer sheet adhesively.

According to the present invention, an effective I methodand apparatus has been developed for transferring a toner image from a toner substrate to atransfer sheet, wherein the toner substrate and transfersheet are brought together, in face to face contact, and a high frequency low amplitude vibration is applied to said substrate and sheet while they arein contact with each other. -Any suitable means can be used to bring the toner substrate and transfer she'etinto mutual contact, such as for example, a pair of rollers, and thevibration can-be ofmechanic'al or electrical origin. In the case where a pair of opposed rollers are used, the vibration can be applied to the rollers at the point where the toner substrate and the transfer sheet are brought into contact with each other, that is, where they pass through the nip of the rollers. The vibration of the rollers is transferred to said substrate and transfer sheet while they are in contact with each other. Simultaent to those skilled in the artfrom this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will-become more fully understood from the detailed description given hereinbelow in conjunction with the accompanying drawings, which are given by way of illustration only and thus are not limitative of the present invention, and wherein the single FIGURE of thef'present invention shows a schematic illustration of a side view of an apparatusfor transferring a toner image from a toner substrate to a transfer sheet.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiment of the present invention shown in the drawing, a toner substrate 3 containing toner image 4 formed thereon is conveyedtogether with a transfer sheet 5 through the nip of a pair of opposed pinch rollers 1 and 2. A vibrator 7 bears against the axle of roll 2 to produce a vibration which, in the embodiment shown, is substantially perpendicular to the direction of travel of the-toner substrate and transfer sheet and is I applied to the substrate 3 and sheet 5 at the nip of the rollers. Alternatively, the vibrator may be positioned to contact any part of roller 2, or any part of roller I if desired. The amplitude of vibration of the roller can be ment, wherein a vibration is applied .to said substrate andelement while they are in contact with each other.-

Another object of the present invention is toprovid e a method and apparatus for transferring a toner image from a toner substrate to a transfer sheet wherein, in addition to said vibration. the toner substrate and the varied widely, though it is preferred to be in the range of about several microns to several hundred microns. The .frequency of vibration. is somewhat dependent upon the running speed of the rollers. For example, where the running speed of the rollers is slow, the frequency of vibration may also be relatively small, whereas when the rollers are running at a fast speed, the frequency would have to be proportionately greater. When the rollers are running at a speed of about 5 cm/sec., the frequency of vibration is preferred to be about 1,000 H, or more. When the rollers are running at a speed of about 5 cm/sec., but the frequency is only about 100 H,, the length of each cycle as projected on the transfer sheet would be about 0.5 mm, which would cause toner transfer in streaks of 0.5mm intervals, giving an unacceptable print. If, however, the frequency is increased to about 1,000 Hz. it is difficult to see any streaks because the lengthof each cycle is reduced to about 0.05 mm.

The vibrator may be driven by a piezoelectric element or a magnetostrictive element to which an alternating current is applied in order to obtain the desired vibration. Alternatively, the vibrator may utilize a me-.

' chanical drive.

I Toner transfer'from the substrate 3 to the transfer sheet 5 is effected by a combination of the vibratory action above-described with the simultaneous application of mechanical pressure and/or an electrical voltage across the toner substrate and transfer sheet at the '3 point of toner transfer. For example, in the case where superimposed rollers are used, thepressure is applied between the rollers at the point of contact, and can be the result simply of the weight of the upper r'ollerdisposed upon the lower roller, of if an additional force is desired,theupper roller can be weighted. An electrical field across the nip of rollers. l and 2 can be provided by dc power source 6. The polarity of the power source is selected to provide an opposite polarity on roll 1 backing the transfer sheet 5, from the residual electrostatic charge on the toner particles 4. A protective resistance R is preferably inserted in the electrical circuit which may have a value of between 20 and 1,000 kiloohms.

The pinch rollers l and 2 may, for example, be made of steel, or alternatively, one of the rollers can be a metal roller whereas the other can comprise a metal core covered with an electroconductive material, a semi-conductive material or an insulating rubber. The

toner substrate 3 may comprise, for example, a sheet of EXAMPLE 1 The toner image transfer apparatus comprises two superimposed stainless steel rollers, each having a smooth surface and a diameter of 20 mm. The bearing of the lower roller is fixed and is driven at a speed of 2 cm/sec. by'means of a motor and through the use of a gear reduction system. The'upper roller is supported by a bearing-which is freely self adjusting vertically. The upper roller is superimposed on the lower roller andis driven by the friction created by its weight on the lower roller as the latter rotates. When a toner substrate together with a transfer sheet are feed in face to face contact between the two rollers, the upper roller rises from the lower roller a distance equivalent to the thickness of both materials, and a pressure equivalent to the weight of the upper roller is applied between the rollers. The upper roller is negatively charged from a direct current supply of 1,500 volts, and for safety purposes a resistance of l00,000 ohms is provided in the electrical circuit. A vibrator is in contact with the shaft of the lower roller for vibrating the same at L000 H,.

An electrophotographic substrate comprising electrophotoconductive zinc oxide and an insulating resin coated on a sheet of paper is exposed, and developed with a toner of carbon black coated with a resin and suspended in kerosene. thereby producing a toner image onthe substrate. The toner has a positive charge. After the toner image is formed, the toner substrate is brought into contact with a transfer sheet while in a wet state and passed through the above-described transfer apparatus. Ordinary paper is employedas the transfer sheet. Transfer is carried out uniformly and a high quality'transferredimage is obtained. Good results were also obtained using a vibration frequency of 10 K Hg.

EXAMPLE ll EXAMPLE "I 7 Uniform transfer of the toner image from the toner substrate to the transfer sheet is obtained. using the ap paratus, method andmaterials of Example 1, except no voltage is applied across the rollers, and instead, the roller pressure is increased by the application of a force of 4 Kg between the rollers. Good results are also obtainedwith a vibration frequency of 29 K H,.

EXAMPLE [V In this Example uniform transfer of the tonerimage from the toner substrate to the transfer sheet i's obtained as in Examplell, except no voltage is applied across-the rollers, and instead,therolle'r pressure is increased by the applicationof a force of 6 Kg between the rollers. Also, the upper stainless steel roller in Example II is replaced by a roller having a 10 mm diameter metal core and a 5 mm thick rubber coating. Using a vibration frequency of 1,000 H good transfer results were achieved.

Although, in the above Examples, only one pair of rollers is used, a plurality of pairs of rollers may be employed if it is desired to operate at high speeds.

The invention being thus described, it will be obvious to one skilled in the art that the same may be varied in many ways. Such variations are not to be regarded as departures from the spirit and scope of the invention, and all modifications as are embraced by the appended claims are intended to be included within the purview of the present invention.

What is claimed is:

l. A method of transferring a toner image from a toner substrate to a transfer sheet which comprises bringing the toner substrate bearing the toner image and the transfer sheet together into face to face contact, vibrating said substrate and said sheet while they are in contact with each other and simultaneously applying a transfer means to effect the transfer of said toner image to said transfer sheet.

2. The method as defined in claim 1, wherein said transfer means comprises applying an electric field across the substrate and the sheet.

3. The method as defined in claim 1 wherein said transfer means comprises applying pressure across the substrate and the sheet. a

4. The method as defined in claim 1, wherein the vi bration is substantially perpendicular to the direction of travel of the toner substrate and the transfer sheet.

said rollers is at least about 200 H per cm/sec.

8. The method as defined in claim 1, wherein the toner substrate comprises a sheet of paper coated with a mixture including a photoconductive zinc oxide powder andan insulating resin.

9. The method as defined in claim 1 wherein the transfer sheet is selected from the group consisting of a paper material, a plastic film and a paper material coated with a plastic film.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2843499 *Sep 25, 1956Jul 15, 1958Haloid Xerox IncPressure transfer of xerographic images
US3328193 *Sep 30, 1963Jun 27, 1967Australia Res LabMethod of and means for the transfer of images
US3399111 *Dec 1, 1966Aug 27, 1968Huyck CorpSupplemental belt in combination with an endless belt in papermaking and method of installing the supplemental belt
US3541671 *May 1, 1968Nov 24, 1970Int Standard Electric CorpProcess of fixing paper to metal
US3653948 *Nov 27, 1968Apr 4, 1972Kalle AgProcess and apparatus for compressing string-forming polymer substances by mechanical vibration
US3658519 *Dec 24, 1969Apr 25, 1972Xerox CorpImage transfer process from conductive substrates
US3691993 *Nov 23, 1970Sep 19, 1972IbmApparatus for transferring developed image
US3698314 *Jun 15, 1970Oct 17, 1972Owens Illinois IncMethod for image transfer
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4096826 *May 21, 1976Jun 27, 1978Xerox CorporationMagnetic brush development system for flexible photoreceptors
US4360262 *Oct 24, 1980Nov 23, 1982Pitney Bowes Inc.Electrophotocopier charging and transfer roller
US4903463 *Mar 17, 1989Feb 27, 1990Ford New Holland, Inc.Reciprocating lobed conditioning rolls
US4905459 *Mar 17, 1989Mar 6, 1990Ford New Holland, Inc.In a conditioning mechanism for use in harvesting machine
US4914909 *Mar 17, 1989Apr 10, 1990Ford New Holland, Inc.Lobed ring conditioning roll
US4922692 *Mar 17, 1989May 8, 1990Ford New Holland, Inc.Method of conditioning forage crops
US4977430 *Jun 24, 1988Dec 11, 1990Eastman Kodak CompanyTransfer roller power supply
US4987456 *Jul 2, 1990Jan 22, 1991Xerox CorporationVacuum coupling arrangement for applying vibratory motion to a flexible planar member
US5001030 *Oct 11, 1989Mar 19, 1991Oce-Nederland B.V.Method and means for transferring electrostatically charged image powder
US5005054 *Jul 2, 1990Apr 2, 1991Xerox CorporationFrequency sweeping excitation of high frequency vibratory energy producing devices for electrophotographic imaging
US5010369 *Jul 2, 1990Apr 23, 1991Xerox CorporationSegmented resonator structure having a uniform response for electrophotographic imaging
US5016055 *Jul 2, 1990May 14, 1991Xerox CorporationMethod and apparatus for using vibratory energy with application of transfer field for enhanced transfer in electrophotographic imaging
US5025291 *Jul 2, 1990Jun 18, 1991Zerox CorporationEdge effect compensation in high frequency vibratory energy producing devices for electrophotographic imaging
US5081500 *Jul 2, 1990Jan 14, 1992Xerox CorporationMethod and apparatus for using vibratory energy to reduce transfer deletions in electrophotographic imaging
US5194902 *May 10, 1989Mar 16, 1993Sharp Kabushiki KaishaA transfer belt for toner images from photosensitive means, backup rollers with dielectric films, transfer rollers and plates
US5210577 *May 22, 1992May 11, 1993Xerox CorporationEdge effect compensation in high frequency vibratory energy producing devices for electrophotographic imaging
US5282005 *Jan 13, 1993Jan 25, 1994Xerox CorporationCross process vibrational mode suppression in high frequency vibratory energy producing devices for electrophotographic imaging
US5282006 *Dec 7, 1992Jan 25, 1994Xerox CorporationTransfer system including pre-transfer pressure treatment apparatus
US5329341 *Aug 6, 1993Jul 12, 1994Xerox CorporationOptimized vibratory systems in electrophotographic devices
US5339147 *Nov 24, 1993Aug 16, 1994Xerox CorporationSequential ultrasonic fusing process
US5390013 *Nov 24, 1993Feb 14, 1995Xerox CorporationUltrasonic fusing (ultra-fuse) process
US5477315 *Jul 5, 1994Dec 19, 1995Xerox CorporationElectrostatic coupling force arrangement for applying vibratory motion to a flexible planar member
US5512991 *Nov 14, 1994Apr 30, 1996Xerox CorporationResonator assembly having an angularly segmented waveguide member
US5554334 *Aug 15, 1994Sep 10, 1996Toray Industries, Inc.Method for producing simple printing plate having open cells
US5697035 *Aug 7, 1996Dec 9, 1997Xerox CorporationCylindrical and rotatable resonating assembly for use in electrostatographic applications
US6385429Nov 21, 2000May 7, 2002Xerox CorporationResonator having a piezoceramic/polymer composite transducer
EP0823675A1 *Jul 25, 1997Feb 11, 1998Xerox CorporationCylindrical and rotatable resonating assembly for use in electrostatographic applications
Classifications
U.S. Classification430/125.3, 118/57, 430/108.6, 430/124.23, 101/450.1, 399/319, 101/468, 100/176, 118/638
International ClassificationG03G15/16
Cooperative ClassificationG03G15/167, G03G15/16
European ClassificationG03G15/16F1, G03G15/16