CA1133571A - Offset plate image transfer attachment for graphic art cameras - Google Patents
Offset plate image transfer attachment for graphic art camerasInfo
- Publication number
- CA1133571A CA1133571A CA304,495A CA304495A CA1133571A CA 1133571 A CA1133571 A CA 1133571A CA 304495 A CA304495 A CA 304495A CA 1133571 A CA1133571 A CA 1133571A
- Authority
- CA
- Canada
- Prior art keywords
- toning
- station
- transfer
- web
- film portion
- 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
Links
- 238000012546 transfer Methods 0.000 title claims abstract description 113
- 239000000463 material Substances 0.000 claims abstract description 11
- 238000000034 method Methods 0.000 claims description 25
- 230000007246 mechanism Effects 0.000 claims description 22
- 239000007788 liquid Substances 0.000 claims description 19
- 238000004140 cleaning Methods 0.000 claims description 16
- 239000012876 carrier material Substances 0.000 claims description 15
- 239000012530 fluid Substances 0.000 claims description 12
- 238000003384 imaging method Methods 0.000 claims description 4
- 230000003287 optical effect Effects 0.000 claims description 4
- 239000004020 conductor Substances 0.000 claims 2
- 238000005096 rolling process Methods 0.000 claims 2
- 229910052709 silver Inorganic materials 0.000 abstract description 9
- 239000004332 silver Substances 0.000 abstract description 9
- -1 silver halide Chemical class 0.000 abstract description 9
- 238000007645 offset printing Methods 0.000 abstract description 4
- 229910052782 aluminium Inorganic materials 0.000 abstract description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 abstract description 3
- 239000000758 substrate Substances 0.000 abstract description 2
- 239000002245 particle Substances 0.000 description 12
- 238000010586 diagram Methods 0.000 description 9
- 238000000605 extraction Methods 0.000 description 9
- 239000007921 spray Substances 0.000 description 5
- 238000007639 printing Methods 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 229920000728 polyester Polymers 0.000 description 2
- WUPHOULIZUERAE-UHFFFAOYSA-N 3-(oxolan-2-yl)propanoic acid Chemical compound OC(=O)CCC1CCCO1 WUPHOULIZUERAE-UHFFFAOYSA-N 0.000 description 1
- 102100026933 Myelin-associated neurite-outgrowth inhibitor Human genes 0.000 description 1
- 239000003082 abrasive agent Substances 0.000 description 1
- WYTGDNHDOZPMIW-RCBQFDQVSA-N alstonine Natural products C1=CC2=C3C=CC=CC3=NC2=C2N1C[C@H]1[C@H](C)OC=C(C(=O)OC)[C@H]1C2 WYTGDNHDOZPMIW-RCBQFDQVSA-N 0.000 description 1
- 229910052980 cadmium sulfide Inorganic materials 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- AMGQUBHHOARCQH-UHFFFAOYSA-N indium;oxotin Chemical compound [In].[Sn]=O AMGQUBHHOARCQH-UHFFFAOYSA-N 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 239000013080 microcrystalline material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229920002120 photoresistant polymer Polymers 0.000 description 1
- 229920000136 polysorbate Polymers 0.000 description 1
- 108010021724 tonin Proteins 0.000 description 1
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
- G03G15/10—Apparatus for electrographic processes using a charge pattern for developing using a liquid developer
- G03G15/101—Apparatus for electrographic processes using a charge pattern for developing using a liquid developer for wetting the recording material
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/22—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20
- G03G15/26—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 in which the charge pattern is obtained by projection of the entire image, i.e. whole-frame projection
- G03G15/263—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 in which the charge pattern is obtained by projection of the entire image, i.e. whole-frame projection using a reusable recording medium in form of a band
Abstract
ABSTRACT
A transfer attachment for a graphic art camera taking the place of the ordinary silver halide film cartridge.
The attachment includes an endless web including at least a portion of flexible electrophotographic film. The electro-photographic film is rotated past a source of corona, then to an exposure station, then rotated through a toning station where toner is applied to the film portion, and then to a transfer station where an image is transferred from the film portion onto a second medium. The second medium is generally a plate material such as paper, aluminum, plastic or other flexible substrate material suitable for use in an offset printing press.
A transfer attachment for a graphic art camera taking the place of the ordinary silver halide film cartridge.
The attachment includes an endless web including at least a portion of flexible electrophotographic film. The electro-photographic film is rotated past a source of corona, then to an exposure station, then rotated through a toning station where toner is applied to the film portion, and then to a transfer station where an image is transferred from the film portion onto a second medium. The second medium is generally a plate material such as paper, aluminum, plastic or other flexible substrate material suitable for use in an offset printing press.
Description
~ 3 ~
The invention relates to the making o~ offset printing plates and more particularly to a transfer attachment for a camera for transferring an image from an electrophotograp~ic film to a plate material.
Offset plates are made photographically by complex methods requiring the use of silver halide film, photoresists~
and the processing o~ the images to achieve their incorporation onto plates that can be used on printing presses. In recent years electrostatic techniques have also been used to make such plates, but their quality is so inferior to the quality of photographically made plates that this type of technique is utilized rarely.
The invention herein revolves around a type of electrophotographic film that is capable of being imaged with quality and grey scale as good as, if not bett~er than, that achieved by photographic techniques and with resolution that is better than that achieved by photographic techni~ues The film includes an inorganic coating of microcrystalline material that is bonded onto a polyester substrate with an intervening ohmic layer to aid in charging the film. The film material comprises a coating of radio frequency sputtered cadmium sulfide that is from about 2,000 Angstroms to abou-t -~
The invention relates to the making o~ offset printing plates and more particularly to a transfer attachment for a camera for transferring an image from an electrophotograp~ic film to a plate material.
Offset plates are made photographically by complex methods requiring the use of silver halide film, photoresists~
and the processing o~ the images to achieve their incorporation onto plates that can be used on printing presses. In recent years electrostatic techniques have also been used to make such plates, but their quality is so inferior to the quality of photographically made plates that this type of technique is utilized rarely.
The invention herein revolves around a type of electrophotographic film that is capable of being imaged with quality and grey scale as good as, if not bett~er than, that achieved by photographic techniques and with resolution that is better than that achieved by photographic techni~ues The film includes an inorganic coating of microcrystalline material that is bonded onto a polyester substrate with an intervening ohmic layer to aid in charging the film. The film material comprises a coating of radio frequency sputtered cadmium sulfide that is from about 2,000 Angstroms to abou-t -~
2 microns thick disposed upon a layer of about 300 to 500 Angstroms thick of indium tin oxide which in turn is disposed on a sheet of stable polyester plastic about 5 microns thick.
one such film material is described in U.S. Patent No. 4,025,339 issued May 24, 1977.
~.
The film may be exposed at a high speed and transferred immediat~ly to a carrier such as paper, aluminum, plastic and the li~e which enables the entire process to be carried out inside of an attachment or cartridge which takes the place of the usual silver halide photographic film cartridge that is currently used with graphic art cameras. Besides the elimination of the silver halide film this eliminates considerable processing since the carrier or plate medium with the transfer image may be fixed and directly immersed in a suitable bath to render the toned and untoned parts of the ; image ink receptive and ink repellant, respectively and then utilized directly as a printing plate in a press.
The disadvantages of the previous proposals may be overcome by replacing a graphic art silver halide film cartridge with an attachment having an endless web including at least a portion of electrophotographic film onto which an image may be formed. The film portion is rotated to and charged by a corona source, rotated to an exposure station where an image is formed, then rotated to a toner station where toner is applied to the image and finally to a transfer station where the image is transferred from the film portion onto a second medium, such as a plate material for use in an offset ~rinting press.
This aliminates the silver halide film as well as the consider-able processing necessary for silver halide film.
~3~5'7~
The preferred embodiments of this inven~ion will now be described, by way of example, with reference to the drawings accompanying this specification in which:
Figure 1 is a perspective partially sectional view of one embodiment of the transfer attachment of the invention;
Figure 2 is a diagram of the attachment of Figure 1 showing the basic parts and construction thereof;
Figure 3 is a timing diagram illustrative of the operation of the attachment;
Figure 4 is a perspective diagram of a second embodiment of the attachment;
Figure 5 is a diagram of the embodiment of Figure 4 showing a second type of transfer mechanism;
Figure 6 is an enlarged diagram of the toner station of Figure 4;
Figure 7 is a diagram of another embodiment of the toner station to be used with the attachment; and Figure 8 is a side sectional view of a toning manifold which may be used with the attachment.
Offset printing plates are made by a technique which requires that the image to be incorporated into the plate be photographed. The cameras which are used are specialized for the purpose and commence the process by exposing silver halide film contained in cartridges that are secured to the back of the camera at the image plane thereof. The attachment o~ the invention is intended to replace the silver halide film cartridges and may be utilized with graphic art cameras and other cameras only requiring that the camera ~3;~5'7~
system contain the conventional lenses, shutters, and focusing equipment to expose the film portion by contact, projection or reflection of an object.
Figures 1 and 2 illustrate one embodiment of the attachment 10 of the invention. The camera system is only shown diagrammatically by a lens 12 but would include the elements previously mentioned. The attachment 10 has been shown totally exposed; however, of course, the attachment IO
and the lens 12 would be married together such that no light would enter the system except as desired through the lens 12.
In this respect a cover would be fastened over the attachment 10 which is not illustrated.
The attachment 10 includes a sequence o~ stations incluaing a charging station 14, an exposure station 16, a toning station 18 and a transfer station 20 which may be ~ollowed by an optional cleaning station 22. An endless web 24 is rotated through the stations and the web includes a portion of electrophotographic film upon which the image may be projected and transferred from. The web 24 need only contain a portion of electrophotographic ~ilm large enough to cover the area to be imaged in the exposure station 16;
however, the web 24 may be made entirely from the electro-photographic fi]m. One electrophoto~raphic film which may be utilized in the invenkion as previously mentioned is described in United States Patent ~o. 4,025,339 issued May 24, 1977.
In operation a starting point on the web 24 is chosen, prior to the ilm portion to be acted upon, such as a point on the periphery of the web 24 which may be a piece of ~ 3~S ~
metallic material or strip 26. The strip 26 may then be optically or magnetically sensed as the web 24 passes to the various stations to control the operations and timing o~ the attachment 10. There may be a second metallic strip 27 on the opposite periphery of the web 24 which may be sensed by sensors on the opposite side of the attachment. The timing of the device may also be accomplished by conventional timing mechanisms such as a timing belt or counter withou~ the use of the sensors and strips.
The overall operation of the attachment 10 will be gi~en prior to the details of the various stations to set forth the environment of the stations. The attachment 10 is operated by starting the web 24 rotating through the various stations When the ~ilm portion to be exposed reaches the charging station 14 it will be charged by a corona source either as it moves by the corona source or by stopping the web and moving the corona relative to the ~ilm portion.
Once the film portion is charged the web is rotated until the film portion is located in the exposure station 16 where it is stopped and exposed by the camera system through the lens 12. The film portion is then rotated through the toning station 18 where toner is applied to the image whic~ has been projected onto the film portion. The web 24 continues to rotate until it reaches the transfer station 20 where the toned image is transferred from the film portion onto a plate or other transfer medium. Once the image has been transferred, the web 24 will continue its rotation through the cleaning station 22 where any remaining toner or other material will ~.3~
be cleaned from both sides o~ the web 24 and the web is then rotated completely around to the start position ready for the next imaging and transfer operation. The cleaning station 22 is optional, because the operation of the transfer attachment 10 to a fully receptive trans~er medium under the proper conditions would remove all the toner ~rom the film portion leaving the film portion ready to be recycled for the next imaging operation without the intervening cleaning step.
The components of the various stations and the detailed operations thereof will now be set forth. The charging s~itation 14 includes a corona voltage source 28 t~hich contains a corona wire or wires 30. The corona voltage sou~ce 28 may be fixed to charge the film portion as it passes over the corona source and wire 30 or it may oscillate to provide an even distribution of charge on the film portion.
The film portion as utilized hereinafter is that portion of the we~ 24 which is chosen to be exposed in the exposure station 16. The film portion may also be stopped and the corona source ~8 may be moved across the film portion to provide the even distribution of charge on-the film portion.
The corona source 28 will preferably be operatea at a voltage of approximately 6,000 volts.
Once the film portion is charged to 8 x 10 coulombs/cm or 30 volts e~uivalent the charged film portion is moved into the exposure station 16. The exposure station 16 includes an exposure platen 32 which is disposed above the web 24 with a lower smooth planar surface 34 disposed below -the ~13~
untensioned plane of the web 24 between the rollers 36 and 38. The surface may be beveled at each end to facilitate the passage of the web thereover and the surface will be located in the image plane of the camera system and lens 12.
S Thus, the web 24 will be drawn tightly and smoothly across ; the bottom surface 34 so that a smooth unwrinkled surface will be presented to the camera system and lens 12. To further facilitate the passage of the web 24 past the platen 32, the platen 32 is preferably provided with a series of passageways (not shown) disposed across and opening to the bottom surface 34 which are connected to a source ~f positive fluid pressure (not shown). The pressure source is energized when the belt 24 is moving, but is deenergiæed when the belt is stopped in the exposure station 16 so that the film 24 will be drawn against the smooth platen surface 34.
Once the film portion has been exposed it is rotated -over the ohmic roller 3~ and across -the airection rolls 40 and 42 in the toning station 18. The web 24 is tensioned between the direction rolls 40 and 42 to form a smooth planar reach with a gap between the film portion and a toning platen 44. The toner in liquid or dry form is applied in the gap.
Preferably, the toner in liquid form is supplied through at least one of a pair of manifolds 46 and 48 (Fig. 1).
Pre~erably the manifold 46 is used in conjunction with the manifold 48 to form a smooth nonturbulent flow of toner in the ~ap formed between the toning platen 44 and the film portion. A toning bias, preferably, is electrically applie between the toning platen 44 and the web 24 to assi-st in the J'\ ,:`
..
~3~7~
: toner particles adhering to an ima~e on the film por-tion.
The toning platen 44 has an upper generally planar surface 50 between the rolls 40 and 42 to maintain the gap between the film portion and the toning platen. An upper shoe 51 may be utilized which has a bottom planar surface 52 disposed parallel to the surface 50. The surface 52 keeps - the film portion planar between -the rolls 40 and 42 to precisely maintain the gap. The toning bias may be in a range of negative 5-25 volts, preferably about 11 volts.
The gap may be in a range of 5 to 40 mils, preferably about 12 mils. The upper surface 50 of the toning platen 44 is smoothly polished so that the toning particles and fluid will flow smoothly over the surface thereof and not become adhered to any particular portion thereof.
Any excess toner is removed from the film portion by an extraction roller 53 as the film portion passes by the extraction roller. The extraction roller 53 is spaced from the web 24 which space may be less than 6 mils, preferably about 4 mils, and it is electrically biased to withdraw the toner particles which are not firmly biased to withdraw the toner particles which are not firmly adhered to the imaged portion of the film. The bias may be in a range of negative 20-250 volts, preferably about 135 volts.
The toner particles and liquid are removed from the extraction roller 53 by a squeegee 54. The toner which is not utilized and the fresh toner are cap-tured in a tray or reservoir 56 which is located benea-th the other components of the toning station 18.
To assis-t in -the extraction of the excess toner particles from the Eilm portion a spray bar 58 is located ~ - 8 -above the extraction roller 53 and will spray a film oE
toner into the gap between the web 24 and the ex~rac-tion roller 53 to provide a medium for the toner particles and the electric field between the extraction roller and the film to allow the excess toner particles to be removed.
The web and film portion continue rotating from the toner station 18 over a guide or direction roller 60 to the transfer station 20. The.trans:~er station is pre:~erably loaded with a trans~er or plate medium 62 prior to the start o~ the operation of the attachment. The medium 62 is loaded into a first chute 64 which directs the medium past a tangent point oE the web 24 but spaced thereErom. The web 24 passes over another roller 66 in the transfer station 20 which locates the web and the film portion as it passes through the transfer station. A freely rotatable transfer -roller 68 is disposed for pivotal movement away from and in close proximity to the web 24 such as on a pivot arm 70, The transfer medium 62 such as a piece oE paper extends be-tween the two rollers 66 and 68, but is not in contact with the web 24. Preferably, the medium 62 will extend into a discharge chute 72 to precisely locate the medium 62. When the fron-t edge of the imaged portion arrives in the transfer station 20, the trans~er roller 68 is pivoted against the medium 62 to bring it into close proximity with the web 24 to transfer the image to the medium 62 which will rotate with the rotating belt 24 between the rollers 66 and 68. A
_ g _ t~
.,. , . , " . ~
~ ~3;:~5~
`~ -trallsEeL bias mc~y be applie~ ~t-/een Lhe ro~l~r 6~ alld ~he web 2~1 and m~ be in -the rancJe of nec~ative 250-1200 volts.
The trallsfer bias should be just sufficient -to fully -transEer all~ toned imacJe and will preEerably be about ne;~ative 500 volts. The roller G8 may brincJ the m.diuln 62 directly ac~ainst the fllm portion or may leave a slicJht c~ap to avoid mechanical smearinCJ o~ tlle im~ge i~ th~ me~ium 62 will not absorb the fluid surro~nc~in~ the ton~r particl~s on the f iln~ portion. The gap may be in the ran~e of 0-4 microns.
The web 24 then moves on into the cleaning station 22 - where it passes around another roller 7~ and past a foam cleaning brush 7~ which dislodc~es àny firmly a-ttachèd toner particles or other Material wllicll have not been removed by the -transfer operation. The web 24 then passes pas-t a cleanincJ spray bar 78 which sprays a cleaning ~luid against the film which is squee~eed by an air brush or knife 80 which provides a smooth flow of air across the widtll of the film and may contain a fluid baEfle (not shown). The nozzle 20 ot the air brush 80 is coated with a non-abrasive material;
however, the web and film portion thereof preferably will not touch the air brush due to the flow oE -tlle air from the nozzle. The cleaning solution and excess toner particles are cau~ht in a reservoir 82 loca-ted at -the bottom of the cleaning station 22. The back or inside of thè web 2'~ is cleaned by a squeegee 8~ as it passes the adjustablc ohmic ~uide roller 36.
Tlle ohmic roller 36 has an acljus-tment at each end 86, one of W]liCll is sllown, to steer the web aroull(l tlle se~ts of rollcrs ~ ' -- 1 0 ~1 13~5~7~
in the attachment 10 without excessive lateral movement thereof. The web 24 then continues through the other sta-tions without their being energized and returns to the initial or stop position ready for another cycle. As previously mentioned with the proper biasing, toning and transfer conditions cleaning station 22 may be eliminated.
Referring now to Figure 3, a timing diagram ~or the attachment 10 is illustrated; however, it should be noted that the time factor between each of the times To through Tlo is not drawn to scale and these will vary as determined by a particular operation, size of components, etc. The operation will be explained with the timing diagram utilizing the sensors Al through A6 which sense the metallic strips 26, 27 along the peripheries of the web 24, ~
At time To the start mechanism is energized which will ~;
activate a drive motor 88 starting the web rotati~g, energizing the ~ressure valve in the exposure platen 32, rotating the extractor roll 53 and applying the bias to the extractor ro]l~
At time T2, upon sensing the strip 26 by the sensor Al, the corona voltage source 28 will be energized and the charge will ~e applied to the film portion until time T3 when the strip 26 is sensed by the sensor A2. At time T3 the drive mo-tor will stop, the corona voltage source will deenergize, the pressure valve and the exposure platen 32 will deenergize, drawing the film against the platen surface 34. The ex-tractor roll 53 will also stop rotating as it is geared to the drive motor 88; however, it could be kept rotating by a separate drive ;
if desired. The ~ilm portion is then exposed by the camera - 11 - ' , . .
~13qS~
throuyh the lens 12 by openiny a shutter within the camera to project a light image onto the film.
At time T~, prior to the end of the exposure and the restart of the rotation of the web 24, the toner pump ; 5 (not shown) will be operated to flow toner through the manifolds ~6 and 48 and the extractor spray will be operated to fill the gap between the ex-traction roll 53 and the web 24 with toner so that the extraction roll will be operating properly. At time T5 when the film portion has been properly exposed, an elapsed time of 1-10 seconds,, the drive motor 88, the pressure valve in the platen 32, the toner bias on the platen 44 and the extractor drive are actuated. The film portion then moves through the toner station 18 and is sensed by the sensor A3 at time T6 indicating that the fi-m portion has passed through the toning station. This will deactuate -the toner pump and toner bias and the film portion will be transported to the transfer station 20 during the time period from T6 to time T7.
At time T7 when the strip 26 is sensed by the sensor A4 the drive motor 88 will increase its speed for the transfer operation as it has been found -that the toning operation is more successful at a lower speed than the transfer operation, The web 2~ ma~ move through the toning station at approximately S inches/second and may be transferred at a speed of approximately 8 inches/second. As the front edge of the film portion moves into the transfer station 20 the strip 27 is sensed by the sensor A5 at time ~8 which actuates the bias on the transfer roller 68 at the same time it is actuated .~
` ~133~i7:~L
to move against the medium 62 and press it into close proximity with the belt 24 to pass the medium 62 intimately against the film portion of the web 24 as it passes between the two rollers 66 and 68. The first time that ~he strip 26 is sensed by the sensor A6 at time Tg it ener~izes the components of the cleaning station 22 and the web 24 then rotates through each of the stations to clean off any residual material from the belt. When the sensor A6 senses the strip 26 a second time at time Tlo all the systems and stations are deactivated and the web 24 is stopped ready for the next imaging and transfer operation.
Referring now to Figures 4 and 5, a second embodiment o~ the attachment 10' is illustrated. In this embodiment, the charging station 14 and the exposure station 16 remain the same as described previously; however, the cleaning station 22 has been eliminated and a different toning station 18' and transfer station 20' are utilized. The basic operation, with the exception of the cleaning operation, remains the same as described previously. The various rollers of Figures 1 and 2 have been replaced by two main support rollers 90 and 92, one or both of which are engaged with the motor to frictionally rotate the belt 24 as before. A third adjustable steering roller 94 is inserted in one end of the belt 24 to assure proper alignment of the belt in a like manner as the adjustable roller 36. The roller 94 is connected to a swivel bar 96 which is secured to adjustably pivot around a center point 98 to properly adjust the tracking of the web 24. ~
The center point 98 could of course be replaced by two or ~ -~ "
more adjustable points on the outer ends of the swivel bar 96 as described before.
The film portion on the web 24 is again charged and exposed as before; however, the toner is applied b~ a rotating toner ~eed roll 100 which adhesi~ely picks up the toner from the toner tray or reservoir 56 and applies the toner in a smooth uniform manner across the width of the film portion o~ the web 24. As previously mentioned, the toning platen 44 and the upper shoe 51 may be provided to maintain the optimum gap between the web 24 and the toning platen 44. The toner stations 18 and 18' are, of course, interchangeable as desired.
Once the film portion has been toned it continues around the roller 94 to the transfer station 20'. In this embodiment ``
tne film portion would be rotated until the front edge of the portion is located toward the end of the transfer station 20' The web 24 is then stopped and the medium 62 is then brought into close proximity with the web 24 for the transfer operation. The film portion of the web 24 is brought into close proximity with the medium 62 by a reciprocating transfer roller 102 which is disposed parallel to and below the web 24.
Referring to the timing diagram of Figure 3, the sensors :
A4 and A5 would be replaced b~ a single sensor and the times T7 and T8 would coincide and the drive motor 88 would stop, stopping the ro-tation of the web and the transfer bias would be applied to the medium 62, not to the roller 102. The roller 102 would be activated and move the roller into the position 104 illustrated in phantom to reciproca-te the roll.er - 1133S~
102 across the film portion, sequentially bringing -the ilm portion of the web 24 into close pro~imity or contact with the medium or plate 62 across the entire length thereof.
The roller 102 would then be returned to its initial position away from the web 24.
- One convenient method of locating the medium 62 parallel to the upper reach of the web 24 is a vacuum platen 106.
The vacuum platen 106 has a first open or load position 108 which exposes a bottom planar surface 110 having the vacuum or other negative fluid passageways (not shown),opening :' thereto, The paper or plate material 62 such as aluminum is ; placed onto the platen 106 in the load position 108 and then the vacuum source (not shown) is operated to clamp the plate medium 62 to the platen 106 which is then pivoted or otherwise movea to the transfer or receiving position 112. The platen 106 may contain other means to affix the medium 62 to the surface 110 and may be conveniently moved between the open ~, position 108 and the receiving position 112 by pivoting it around a pivot 11~. The transfer bias would be applied to the platen 106 and when the transfer roller 102 has returned to its start position at time Tg the platen 106 would move from its receiving position 112 to its load and unload position 108 and the cycle would be stopped ready forthe new medium 62 to be loaded in and the next image and transfer operation to take place.
The toning station 18' is best illustrated in Figure 6. '.'' The toner feed roll 100 rotates with its bottom surface submerged in the toner fluid 116 which is kept agitated by a ., .
- ~ ~3357 lL
submerged toner agitator 118 to keep the toner particles from settling to the bottom o~ the tray or reservoir 56 The top of the toner feedroll is positioned approximately 5 to 10 microns from the bottom surface of the web 24. The toner particles adhere to the periphery o~ the roll 100 as it rotates through the fluid 116 and are attracted in the upper position to the film portion of the web 24. The excess toner fluid will be removed from the web 24 when it exits from the toning platen 44 by the extractor roll 53 which is kept clean by the squeegee 54~ The gap between the surfaces 50 and 52 . .
is also more clearly illustrated and is preferably on the order of 5-40 mils with the extraction roll gap being approximately 4 to 6 mils.
Figure 7 illustrates a third embodiment of the toning station 18". In this embodiment a flexible sheet 120 is connected to a pair o~ drive rolls 122 and 124. The rolls 122 and 124 are driven in tandem to rotate the sheet from the roll 122 around a pair of guide rollers 126 and 128 onto .
the second drive roll 124 to apply toner to the film portion -~
as it passes through the toning station 18". The toning ~ :
platen 44, upper shoe 51 and the directional rolls 40 and 42 `
have been shown merely as illustrations and the flexible sheet 120 or window shade type toning station may also be used with the embodiment as shown in Figure 4 with or without the toning ;
platen 44 and the upper shoe 51, depending on the tensi~ning and positioning of the web 24. Once the film has passed through the toning station 18" the drive rolls 122 and 124 reverse and rewind the flexible sheet or window shade 120 : :
. .
. . : - . . - . . - ....... .. : .-. ~.. . .... . . ... .
one such film material is described in U.S. Patent No. 4,025,339 issued May 24, 1977.
~.
The film may be exposed at a high speed and transferred immediat~ly to a carrier such as paper, aluminum, plastic and the li~e which enables the entire process to be carried out inside of an attachment or cartridge which takes the place of the usual silver halide photographic film cartridge that is currently used with graphic art cameras. Besides the elimination of the silver halide film this eliminates considerable processing since the carrier or plate medium with the transfer image may be fixed and directly immersed in a suitable bath to render the toned and untoned parts of the ; image ink receptive and ink repellant, respectively and then utilized directly as a printing plate in a press.
The disadvantages of the previous proposals may be overcome by replacing a graphic art silver halide film cartridge with an attachment having an endless web including at least a portion of electrophotographic film onto which an image may be formed. The film portion is rotated to and charged by a corona source, rotated to an exposure station where an image is formed, then rotated to a toner station where toner is applied to the image and finally to a transfer station where the image is transferred from the film portion onto a second medium, such as a plate material for use in an offset ~rinting press.
This aliminates the silver halide film as well as the consider-able processing necessary for silver halide film.
~3~5'7~
The preferred embodiments of this inven~ion will now be described, by way of example, with reference to the drawings accompanying this specification in which:
Figure 1 is a perspective partially sectional view of one embodiment of the transfer attachment of the invention;
Figure 2 is a diagram of the attachment of Figure 1 showing the basic parts and construction thereof;
Figure 3 is a timing diagram illustrative of the operation of the attachment;
Figure 4 is a perspective diagram of a second embodiment of the attachment;
Figure 5 is a diagram of the embodiment of Figure 4 showing a second type of transfer mechanism;
Figure 6 is an enlarged diagram of the toner station of Figure 4;
Figure 7 is a diagram of another embodiment of the toner station to be used with the attachment; and Figure 8 is a side sectional view of a toning manifold which may be used with the attachment.
Offset printing plates are made by a technique which requires that the image to be incorporated into the plate be photographed. The cameras which are used are specialized for the purpose and commence the process by exposing silver halide film contained in cartridges that are secured to the back of the camera at the image plane thereof. The attachment o~ the invention is intended to replace the silver halide film cartridges and may be utilized with graphic art cameras and other cameras only requiring that the camera ~3;~5'7~
system contain the conventional lenses, shutters, and focusing equipment to expose the film portion by contact, projection or reflection of an object.
Figures 1 and 2 illustrate one embodiment of the attachment 10 of the invention. The camera system is only shown diagrammatically by a lens 12 but would include the elements previously mentioned. The attachment 10 has been shown totally exposed; however, of course, the attachment IO
and the lens 12 would be married together such that no light would enter the system except as desired through the lens 12.
In this respect a cover would be fastened over the attachment 10 which is not illustrated.
The attachment 10 includes a sequence o~ stations incluaing a charging station 14, an exposure station 16, a toning station 18 and a transfer station 20 which may be ~ollowed by an optional cleaning station 22. An endless web 24 is rotated through the stations and the web includes a portion of electrophotographic film upon which the image may be projected and transferred from. The web 24 need only contain a portion of electrophotographic ~ilm large enough to cover the area to be imaged in the exposure station 16;
however, the web 24 may be made entirely from the electro-photographic fi]m. One electrophoto~raphic film which may be utilized in the invenkion as previously mentioned is described in United States Patent ~o. 4,025,339 issued May 24, 1977.
In operation a starting point on the web 24 is chosen, prior to the ilm portion to be acted upon, such as a point on the periphery of the web 24 which may be a piece of ~ 3~S ~
metallic material or strip 26. The strip 26 may then be optically or magnetically sensed as the web 24 passes to the various stations to control the operations and timing o~ the attachment 10. There may be a second metallic strip 27 on the opposite periphery of the web 24 which may be sensed by sensors on the opposite side of the attachment. The timing of the device may also be accomplished by conventional timing mechanisms such as a timing belt or counter withou~ the use of the sensors and strips.
The overall operation of the attachment 10 will be gi~en prior to the details of the various stations to set forth the environment of the stations. The attachment 10 is operated by starting the web 24 rotating through the various stations When the ~ilm portion to be exposed reaches the charging station 14 it will be charged by a corona source either as it moves by the corona source or by stopping the web and moving the corona relative to the ~ilm portion.
Once the film portion is charged the web is rotated until the film portion is located in the exposure station 16 where it is stopped and exposed by the camera system through the lens 12. The film portion is then rotated through the toning station 18 where toner is applied to the image whic~ has been projected onto the film portion. The web 24 continues to rotate until it reaches the transfer station 20 where the toned image is transferred from the film portion onto a plate or other transfer medium. Once the image has been transferred, the web 24 will continue its rotation through the cleaning station 22 where any remaining toner or other material will ~.3~
be cleaned from both sides o~ the web 24 and the web is then rotated completely around to the start position ready for the next imaging and transfer operation. The cleaning station 22 is optional, because the operation of the transfer attachment 10 to a fully receptive trans~er medium under the proper conditions would remove all the toner ~rom the film portion leaving the film portion ready to be recycled for the next imaging operation without the intervening cleaning step.
The components of the various stations and the detailed operations thereof will now be set forth. The charging s~itation 14 includes a corona voltage source 28 t~hich contains a corona wire or wires 30. The corona voltage sou~ce 28 may be fixed to charge the film portion as it passes over the corona source and wire 30 or it may oscillate to provide an even distribution of charge on the film portion.
The film portion as utilized hereinafter is that portion of the we~ 24 which is chosen to be exposed in the exposure station 16. The film portion may also be stopped and the corona source ~8 may be moved across the film portion to provide the even distribution of charge on-the film portion.
The corona source 28 will preferably be operatea at a voltage of approximately 6,000 volts.
Once the film portion is charged to 8 x 10 coulombs/cm or 30 volts e~uivalent the charged film portion is moved into the exposure station 16. The exposure station 16 includes an exposure platen 32 which is disposed above the web 24 with a lower smooth planar surface 34 disposed below -the ~13~
untensioned plane of the web 24 between the rollers 36 and 38. The surface may be beveled at each end to facilitate the passage of the web thereover and the surface will be located in the image plane of the camera system and lens 12.
S Thus, the web 24 will be drawn tightly and smoothly across ; the bottom surface 34 so that a smooth unwrinkled surface will be presented to the camera system and lens 12. To further facilitate the passage of the web 24 past the platen 32, the platen 32 is preferably provided with a series of passageways (not shown) disposed across and opening to the bottom surface 34 which are connected to a source ~f positive fluid pressure (not shown). The pressure source is energized when the belt 24 is moving, but is deenergiæed when the belt is stopped in the exposure station 16 so that the film 24 will be drawn against the smooth platen surface 34.
Once the film portion has been exposed it is rotated -over the ohmic roller 3~ and across -the airection rolls 40 and 42 in the toning station 18. The web 24 is tensioned between the direction rolls 40 and 42 to form a smooth planar reach with a gap between the film portion and a toning platen 44. The toner in liquid or dry form is applied in the gap.
Preferably, the toner in liquid form is supplied through at least one of a pair of manifolds 46 and 48 (Fig. 1).
Pre~erably the manifold 46 is used in conjunction with the manifold 48 to form a smooth nonturbulent flow of toner in the ~ap formed between the toning platen 44 and the film portion. A toning bias, preferably, is electrically applie between the toning platen 44 and the web 24 to assi-st in the J'\ ,:`
..
~3~7~
: toner particles adhering to an ima~e on the film por-tion.
The toning platen 44 has an upper generally planar surface 50 between the rolls 40 and 42 to maintain the gap between the film portion and the toning platen. An upper shoe 51 may be utilized which has a bottom planar surface 52 disposed parallel to the surface 50. The surface 52 keeps - the film portion planar between -the rolls 40 and 42 to precisely maintain the gap. The toning bias may be in a range of negative 5-25 volts, preferably about 11 volts.
The gap may be in a range of 5 to 40 mils, preferably about 12 mils. The upper surface 50 of the toning platen 44 is smoothly polished so that the toning particles and fluid will flow smoothly over the surface thereof and not become adhered to any particular portion thereof.
Any excess toner is removed from the film portion by an extraction roller 53 as the film portion passes by the extraction roller. The extraction roller 53 is spaced from the web 24 which space may be less than 6 mils, preferably about 4 mils, and it is electrically biased to withdraw the toner particles which are not firmly biased to withdraw the toner particles which are not firmly adhered to the imaged portion of the film. The bias may be in a range of negative 20-250 volts, preferably about 135 volts.
The toner particles and liquid are removed from the extraction roller 53 by a squeegee 54. The toner which is not utilized and the fresh toner are cap-tured in a tray or reservoir 56 which is located benea-th the other components of the toning station 18.
To assis-t in -the extraction of the excess toner particles from the Eilm portion a spray bar 58 is located ~ - 8 -above the extraction roller 53 and will spray a film oE
toner into the gap between the web 24 and the ex~rac-tion roller 53 to provide a medium for the toner particles and the electric field between the extraction roller and the film to allow the excess toner particles to be removed.
The web and film portion continue rotating from the toner station 18 over a guide or direction roller 60 to the transfer station 20. The.trans:~er station is pre:~erably loaded with a trans~er or plate medium 62 prior to the start o~ the operation of the attachment. The medium 62 is loaded into a first chute 64 which directs the medium past a tangent point oE the web 24 but spaced thereErom. The web 24 passes over another roller 66 in the transfer station 20 which locates the web and the film portion as it passes through the transfer station. A freely rotatable transfer -roller 68 is disposed for pivotal movement away from and in close proximity to the web 24 such as on a pivot arm 70, The transfer medium 62 such as a piece oE paper extends be-tween the two rollers 66 and 68, but is not in contact with the web 24. Preferably, the medium 62 will extend into a discharge chute 72 to precisely locate the medium 62. When the fron-t edge of the imaged portion arrives in the transfer station 20, the trans~er roller 68 is pivoted against the medium 62 to bring it into close proximity with the web 24 to transfer the image to the medium 62 which will rotate with the rotating belt 24 between the rollers 66 and 68. A
_ g _ t~
.,. , . , " . ~
~ ~3;:~5~
`~ -trallsEeL bias mc~y be applie~ ~t-/een Lhe ro~l~r 6~ alld ~he web 2~1 and m~ be in -the rancJe of nec~ative 250-1200 volts.
The trallsfer bias should be just sufficient -to fully -transEer all~ toned imacJe and will preEerably be about ne;~ative 500 volts. The roller G8 may brincJ the m.diuln 62 directly ac~ainst the fllm portion or may leave a slicJht c~ap to avoid mechanical smearinCJ o~ tlle im~ge i~ th~ me~ium 62 will not absorb the fluid surro~nc~in~ the ton~r particl~s on the f iln~ portion. The gap may be in the ran~e of 0-4 microns.
The web 24 then moves on into the cleaning station 22 - where it passes around another roller 7~ and past a foam cleaning brush 7~ which dislodc~es àny firmly a-ttachèd toner particles or other Material wllicll have not been removed by the -transfer operation. The web 24 then passes pas-t a cleanincJ spray bar 78 which sprays a cleaning ~luid against the film which is squee~eed by an air brush or knife 80 which provides a smooth flow of air across the widtll of the film and may contain a fluid baEfle (not shown). The nozzle 20 ot the air brush 80 is coated with a non-abrasive material;
however, the web and film portion thereof preferably will not touch the air brush due to the flow oE -tlle air from the nozzle. The cleaning solution and excess toner particles are cau~ht in a reservoir 82 loca-ted at -the bottom of the cleaning station 22. The back or inside of thè web 2'~ is cleaned by a squeegee 8~ as it passes the adjustablc ohmic ~uide roller 36.
Tlle ohmic roller 36 has an acljus-tment at each end 86, one of W]liCll is sllown, to steer the web aroull(l tlle se~ts of rollcrs ~ ' -- 1 0 ~1 13~5~7~
in the attachment 10 without excessive lateral movement thereof. The web 24 then continues through the other sta-tions without their being energized and returns to the initial or stop position ready for another cycle. As previously mentioned with the proper biasing, toning and transfer conditions cleaning station 22 may be eliminated.
Referring now to Figure 3, a timing diagram ~or the attachment 10 is illustrated; however, it should be noted that the time factor between each of the times To through Tlo is not drawn to scale and these will vary as determined by a particular operation, size of components, etc. The operation will be explained with the timing diagram utilizing the sensors Al through A6 which sense the metallic strips 26, 27 along the peripheries of the web 24, ~
At time To the start mechanism is energized which will ~;
activate a drive motor 88 starting the web rotati~g, energizing the ~ressure valve in the exposure platen 32, rotating the extractor roll 53 and applying the bias to the extractor ro]l~
At time T2, upon sensing the strip 26 by the sensor Al, the corona voltage source 28 will be energized and the charge will ~e applied to the film portion until time T3 when the strip 26 is sensed by the sensor A2. At time T3 the drive mo-tor will stop, the corona voltage source will deenergize, the pressure valve and the exposure platen 32 will deenergize, drawing the film against the platen surface 34. The ex-tractor roll 53 will also stop rotating as it is geared to the drive motor 88; however, it could be kept rotating by a separate drive ;
if desired. The ~ilm portion is then exposed by the camera - 11 - ' , . .
~13qS~
throuyh the lens 12 by openiny a shutter within the camera to project a light image onto the film.
At time T~, prior to the end of the exposure and the restart of the rotation of the web 24, the toner pump ; 5 (not shown) will be operated to flow toner through the manifolds ~6 and 48 and the extractor spray will be operated to fill the gap between the ex-traction roll 53 and the web 24 with toner so that the extraction roll will be operating properly. At time T5 when the film portion has been properly exposed, an elapsed time of 1-10 seconds,, the drive motor 88, the pressure valve in the platen 32, the toner bias on the platen 44 and the extractor drive are actuated. The film portion then moves through the toner station 18 and is sensed by the sensor A3 at time T6 indicating that the fi-m portion has passed through the toning station. This will deactuate -the toner pump and toner bias and the film portion will be transported to the transfer station 20 during the time period from T6 to time T7.
At time T7 when the strip 26 is sensed by the sensor A4 the drive motor 88 will increase its speed for the transfer operation as it has been found -that the toning operation is more successful at a lower speed than the transfer operation, The web 2~ ma~ move through the toning station at approximately S inches/second and may be transferred at a speed of approximately 8 inches/second. As the front edge of the film portion moves into the transfer station 20 the strip 27 is sensed by the sensor A5 at time ~8 which actuates the bias on the transfer roller 68 at the same time it is actuated .~
` ~133~i7:~L
to move against the medium 62 and press it into close proximity with the belt 24 to pass the medium 62 intimately against the film portion of the web 24 as it passes between the two rollers 66 and 68. The first time that ~he strip 26 is sensed by the sensor A6 at time Tg it ener~izes the components of the cleaning station 22 and the web 24 then rotates through each of the stations to clean off any residual material from the belt. When the sensor A6 senses the strip 26 a second time at time Tlo all the systems and stations are deactivated and the web 24 is stopped ready for the next imaging and transfer operation.
Referring now to Figures 4 and 5, a second embodiment o~ the attachment 10' is illustrated. In this embodiment, the charging station 14 and the exposure station 16 remain the same as described previously; however, the cleaning station 22 has been eliminated and a different toning station 18' and transfer station 20' are utilized. The basic operation, with the exception of the cleaning operation, remains the same as described previously. The various rollers of Figures 1 and 2 have been replaced by two main support rollers 90 and 92, one or both of which are engaged with the motor to frictionally rotate the belt 24 as before. A third adjustable steering roller 94 is inserted in one end of the belt 24 to assure proper alignment of the belt in a like manner as the adjustable roller 36. The roller 94 is connected to a swivel bar 96 which is secured to adjustably pivot around a center point 98 to properly adjust the tracking of the web 24. ~
The center point 98 could of course be replaced by two or ~ -~ "
more adjustable points on the outer ends of the swivel bar 96 as described before.
The film portion on the web 24 is again charged and exposed as before; however, the toner is applied b~ a rotating toner ~eed roll 100 which adhesi~ely picks up the toner from the toner tray or reservoir 56 and applies the toner in a smooth uniform manner across the width of the film portion o~ the web 24. As previously mentioned, the toning platen 44 and the upper shoe 51 may be provided to maintain the optimum gap between the web 24 and the toning platen 44. The toner stations 18 and 18' are, of course, interchangeable as desired.
Once the film portion has been toned it continues around the roller 94 to the transfer station 20'. In this embodiment ``
tne film portion would be rotated until the front edge of the portion is located toward the end of the transfer station 20' The web 24 is then stopped and the medium 62 is then brought into close proximity with the web 24 for the transfer operation. The film portion of the web 24 is brought into close proximity with the medium 62 by a reciprocating transfer roller 102 which is disposed parallel to and below the web 24.
Referring to the timing diagram of Figure 3, the sensors :
A4 and A5 would be replaced b~ a single sensor and the times T7 and T8 would coincide and the drive motor 88 would stop, stopping the ro-tation of the web and the transfer bias would be applied to the medium 62, not to the roller 102. The roller 102 would be activated and move the roller into the position 104 illustrated in phantom to reciproca-te the roll.er - 1133S~
102 across the film portion, sequentially bringing -the ilm portion of the web 24 into close pro~imity or contact with the medium or plate 62 across the entire length thereof.
The roller 102 would then be returned to its initial position away from the web 24.
- One convenient method of locating the medium 62 parallel to the upper reach of the web 24 is a vacuum platen 106.
The vacuum platen 106 has a first open or load position 108 which exposes a bottom planar surface 110 having the vacuum or other negative fluid passageways (not shown),opening :' thereto, The paper or plate material 62 such as aluminum is ; placed onto the platen 106 in the load position 108 and then the vacuum source (not shown) is operated to clamp the plate medium 62 to the platen 106 which is then pivoted or otherwise movea to the transfer or receiving position 112. The platen 106 may contain other means to affix the medium 62 to the surface 110 and may be conveniently moved between the open ~, position 108 and the receiving position 112 by pivoting it around a pivot 11~. The transfer bias would be applied to the platen 106 and when the transfer roller 102 has returned to its start position at time Tg the platen 106 would move from its receiving position 112 to its load and unload position 108 and the cycle would be stopped ready forthe new medium 62 to be loaded in and the next image and transfer operation to take place.
The toning station 18' is best illustrated in Figure 6. '.'' The toner feed roll 100 rotates with its bottom surface submerged in the toner fluid 116 which is kept agitated by a ., .
- ~ ~3357 lL
submerged toner agitator 118 to keep the toner particles from settling to the bottom o~ the tray or reservoir 56 The top of the toner feedroll is positioned approximately 5 to 10 microns from the bottom surface of the web 24. The toner particles adhere to the periphery o~ the roll 100 as it rotates through the fluid 116 and are attracted in the upper position to the film portion of the web 24. The excess toner fluid will be removed from the web 24 when it exits from the toning platen 44 by the extractor roll 53 which is kept clean by the squeegee 54~ The gap between the surfaces 50 and 52 . .
is also more clearly illustrated and is preferably on the order of 5-40 mils with the extraction roll gap being approximately 4 to 6 mils.
Figure 7 illustrates a third embodiment of the toning station 18". In this embodiment a flexible sheet 120 is connected to a pair o~ drive rolls 122 and 124. The rolls 122 and 124 are driven in tandem to rotate the sheet from the roll 122 around a pair of guide rollers 126 and 128 onto .
the second drive roll 124 to apply toner to the film portion -~
as it passes through the toning station 18". The toning ~ :
platen 44, upper shoe 51 and the directional rolls 40 and 42 `
have been shown merely as illustrations and the flexible sheet 120 or window shade type toning station may also be used with the embodiment as shown in Figure 4 with or without the toning ;
platen 44 and the upper shoe 51, depending on the tensi~ning and positioning of the web 24. Once the film has passed through the toning station 18" the drive rolls 122 and 124 reverse and rewind the flexible sheet or window shade 120 : :
. .
. . : - . . - . . - ....... .. : .-. ~.. . .... . . ... .
3;~s~
onto the roll 122. The toner may be picked up by the sheet as it unwinds from the roll 122 or may be applied by a mani~old like the manifold 46 of Figures 1 and 2 after it has passed over the roll 126.
The design of the tonin~ manifolds 46 and 48 and the air kni~e or air brush 80 is most clearly illustrated in Figure 8, where the manifold 46 is shown in section. The fluid air or toner is applied by a pump to one or a number of ports 130 connected to a plurality of passageways 132 which direct the fluid into a first.chamber 134. The chamber 134 as well as each of the succeeding chambers and baffles extends the width of the manifold which is of a width substantially equal to the imaged film portion of the web 24. ~hen the fluid has filled the first cha~ber 134 it will 1OW through a narrow passageway 136 into the second chamber 138 in a serpentine fashion and from the chamber 138 through a passageway 140 into a third chamber 142 and in a like manner from the third chamber 142 through a confining . .;
passage 144 to an exit or nozzle sli-t 146 in a smooth nonturbulent even flow across the width of the nazzle 146 assuring a substantially constant even flow of taner across the width of the web 24. The manifold 46 may be formed from ; .
a single block or may be ~ormed from an upper block portion ~
148 mated with a lower block portion 150 to form the;~.
passageways and chambers therebetween.
The toner preferably will not be applied across the entire ~:
width of the web 24 so that the back of the web will remain dry for the motor 88 to frictionally drive the web through - 17 - :
f 1~3;~S~l one or more of the rolls. Pre~erably the roll 74 will be driven as the web 24 makes a 180 wraparound this roll~
Each of the rolls is preferably made of metal to secure the proper dimension and to make ohmic contact through the rolls.
36 and 38.
~/'`' ~
SUPPLEMENTAR~ L):~SCLOSURl `- 1~ 57~L
An electrophotographic attachment as described in the foregoing disclosure may be modified for use with an optical projecting system for the purpose of making a copy of a document on a sheet of carrier material, where the delivered produc-t is not required to be used or converted to an offset prin-ting plate. Such modification may involve the omission of the expo-sure platen 32 and utilizing the rollers 36 and 38 to maintain adequate tension of the web 24 so that the said web is placed at the image plane of the camera system and lens 12. The precision requiring use of the platen when an offse-t printing plate is to be formed and delivered by apparatus 10 is not required where the delivered product comprise mere copies of the original subject matter.
The optical system may comprise a camera or may comprise a light source, lens system and a shutter -to control the light conditions for e~posure and for toning. ~
-19- :
~,'~'`', ~
~L33Sttl~L
Figure 9 is a clia~ram oE s-till another embodiment of the toner s-tation to be used with the at-tachment.
. , _ . . ~ . . . . . . ..
~1 3~5~
Referring now to Figure 9, -tllere is ilLustratecl a fourth embodiment of toning station 18'''. In tiliS embodimen-t, rollers 40, 42 and 60 of -the Figure l embodiment have been replaced by a single roller 200 which is couple~ to the drive m~tor to ~unctionally drive belt 24. A reservoir 56' containing a supply liauid toner LT is located below roller 200. Reservoir 56' in-cludes an arcuate planar top surface 50' which is metallized, has a transverse slot at the center and functions as a toning platen 44'. The gap between top surface 50' and belt 24 is on ~he order of 5 to 40 mils. A toner feed roller lO0' is position-ed so as to extend out slightly from the central slot in surface 50' and is mechanically coupled, by means not shown, to drive roller 24. The space between feed roller lO0' and the bo-ttom surface of web 24 is on the order of about 5 mils. In operation toner LH is carried up from inside reservoir 56' by feed roller lO0' to the space between toning platen top surface 50' and belt 24 and is attracted to the latent image on belt 24. A suitable bias may be applied between surface 50' and belt 24 to assist in the attraction of toner LT to the belt 24. Excess toner LT is recaptured through suitably located openings in reservoir 56'.
.
onto the roll 122. The toner may be picked up by the sheet as it unwinds from the roll 122 or may be applied by a mani~old like the manifold 46 of Figures 1 and 2 after it has passed over the roll 126.
The design of the tonin~ manifolds 46 and 48 and the air kni~e or air brush 80 is most clearly illustrated in Figure 8, where the manifold 46 is shown in section. The fluid air or toner is applied by a pump to one or a number of ports 130 connected to a plurality of passageways 132 which direct the fluid into a first.chamber 134. The chamber 134 as well as each of the succeeding chambers and baffles extends the width of the manifold which is of a width substantially equal to the imaged film portion of the web 24. ~hen the fluid has filled the first cha~ber 134 it will 1OW through a narrow passageway 136 into the second chamber 138 in a serpentine fashion and from the chamber 138 through a passageway 140 into a third chamber 142 and in a like manner from the third chamber 142 through a confining . .;
passage 144 to an exit or nozzle sli-t 146 in a smooth nonturbulent even flow across the width of the nazzle 146 assuring a substantially constant even flow of taner across the width of the web 24. The manifold 46 may be formed from ; .
a single block or may be ~ormed from an upper block portion ~
148 mated with a lower block portion 150 to form the;~.
passageways and chambers therebetween.
The toner preferably will not be applied across the entire ~:
width of the web 24 so that the back of the web will remain dry for the motor 88 to frictionally drive the web through - 17 - :
f 1~3;~S~l one or more of the rolls. Pre~erably the roll 74 will be driven as the web 24 makes a 180 wraparound this roll~
Each of the rolls is preferably made of metal to secure the proper dimension and to make ohmic contact through the rolls.
36 and 38.
~/'`' ~
SUPPLEMENTAR~ L):~SCLOSURl `- 1~ 57~L
An electrophotographic attachment as described in the foregoing disclosure may be modified for use with an optical projecting system for the purpose of making a copy of a document on a sheet of carrier material, where the delivered produc-t is not required to be used or converted to an offset prin-ting plate. Such modification may involve the omission of the expo-sure platen 32 and utilizing the rollers 36 and 38 to maintain adequate tension of the web 24 so that the said web is placed at the image plane of the camera system and lens 12. The precision requiring use of the platen when an offse-t printing plate is to be formed and delivered by apparatus 10 is not required where the delivered product comprise mere copies of the original subject matter.
The optical system may comprise a camera or may comprise a light source, lens system and a shutter -to control the light conditions for e~posure and for toning. ~
-19- :
~,'~'`', ~
~L33Sttl~L
Figure 9 is a clia~ram oE s-till another embodiment of the toner s-tation to be used with the at-tachment.
. , _ . . ~ . . . . . . ..
~1 3~5~
Referring now to Figure 9, -tllere is ilLustratecl a fourth embodiment of toning station 18'''. In tiliS embodimen-t, rollers 40, 42 and 60 of -the Figure l embodiment have been replaced by a single roller 200 which is couple~ to the drive m~tor to ~unctionally drive belt 24. A reservoir 56' containing a supply liauid toner LT is located below roller 200. Reservoir 56' in-cludes an arcuate planar top surface 50' which is metallized, has a transverse slot at the center and functions as a toning platen 44'. The gap between top surface 50' and belt 24 is on ~he order of 5 to 40 mils. A toner feed roller lO0' is position-ed so as to extend out slightly from the central slot in surface 50' and is mechanically coupled, by means not shown, to drive roller 24. The space between feed roller lO0' and the bo-ttom surface of web 24 is on the order of about 5 mils. In operation toner LH is carried up from inside reservoir 56' by feed roller lO0' to the space between toning platen top surface 50' and belt 24 and is attracted to the latent image on belt 24. A suitable bias may be applied between surface 50' and belt 24 to assist in the attraction of toner LT to the belt 24. Excess toner LT is recaptured through suitably located openings in reservoir 56'.
.
Claims (57)
1. An electrophotographic imaging and transfer mechanism comprising rotatable endless web means including at least a portion of electrophotographic film and defining substantially parallel first and second planar reaches, said web and film portion including a front or exposure side and a back side, drive means for rotating said web sequentially through a set of stations positioned along said reaches, said set of stations including, a charging station located adjacent said front side including corona means for charging said film portion while it is in said charging station, an exposure station following said charging station including means for locating and stopping said film portion in a plane fox exposure and exposing the electro-photographic portion at a first planar reach, a toning station following said exposure station, including means for applying a substantially constant amount of toner across the width of only said front side of said film portion as it is moved through said toning station, means defining a toning gap between the first planar reach and said applying means for receiving toner from said applying means, and transfer station following said toning station including means for transferring an image from said film portion onto a transfer medium, including means for moving said transfer medium and said front side of said film portion into close proximity during said transfer.
2. A mechanism as defined in claim 1 in which said toner is in liquid form and said toning station includes means for supplying said toner in a smooth and nonturbulent flow to said front side of said film portion.
3. A mechanism as defined in claim 1 in which said toning station includes, toning platen means including a smooth substantially planar surface spaced from said front side, and said supply means include at least first manifold means haying at least a first longitudinal baffle connected to a longitudinal exit for flowing said toner onto said film portion.
4. A mechanism as defined in claim 1 in which said exposure station includes, platen means disposed opposite said back side having a substantially planar surface, said planar surface positioned in said exposure plane and lying below the untensioned plane of said web to press said film portion smoothly against said planar surface.
5. A mechanism as defined in claim 4 in which said platen means include, positive pressure fluid means disposed across said planar surface operable when said web is moving to facilitate the passage of said web through said exposure station past said platen surface.
6. A mechanism as defined in claim 1 in which said toning station includes, toner feed roll means disposed substantially parallel to and adjacent to said front side for feeding toner to said film portion, and toning platen means adjacent to said feed roll means including a smooth surface spaced from said front side.
7. A mechanism as defined in claim 6 in which said toning station includes, bias means for electrically biasing said film portion relative to said toning platen means across the space between them to assist in the toning operation.
8. A mechanism as defined in any one of claims 1, 3 or 6 in which said toning station includes, shoe means including a smooth substantially planar surface disposed against said back side, substantially parallel to the surface of said toning platen means whereby to define said predetermined toning gap.
9. A mechanism as defined in claim 1 in which said toning station includes, toning curtain means including a flexible sheet having a first reach disposed substantially parallel to said front side of said film portion to form said toning gap therebetween as it passes through said toning station, and including means rotating said sheet from a toner supply past said front side of said film portion to supply said toner to said film portion,
10. A mechanism as defined in any one of claims 3, 6 or 9 in which said toning station includes, bias means for electrically biasing said film portion relative to said toning platen means across said gap to assist in the toning operation.
11. A mechanism as defined in claim 9 in which said toning station includes, toning platen means including a smooth substantially planar surface disposed against said flexible sheet in said first reach on the side opposite of said film portion to maintain said gap,
12. A mechanism as defined in claim 11 in which said toning station includes, shoe means including a smooth substantially planar surface disposed against said back side, substantially parallel to said toning platen means planar surface to maintain said gap,
13. A mechanism as defined in any one of claims 1, 2 or 3 in which said transfer station includes, support roll means disposed against said back side for supporting and positioning said web and film portions as it passes through said transfer station, chute means for feeding said transfer medium adjacent to but spaced from said web on said front side, and transfer roll means opposite said support roll means being operative by said moving means to press against said medium to move it into close proximity with said film portion for transferring an image to said transfer medium as it passes through said transfer station between said rolls.
14. A mechanism as defined in any one of claims 1, 2 or 3 in which said transfer station includes, support roll means disposed against said back side for supporting and positioning said web and film portion as it passes through said transfer station, chute means for feeding said transfer medium adjacent to but spaced from said web on said front side, and transfer roll means opposite said support roll means being operative by said moving means to press against said medium to move it into close proximity with said film portion for transferring an image to said transfer medium as it passes through said transfer station between said rolls and said transfer further includes, transfer bias means for electrically biasing said film portion relative to said transfer medium and said transfer roll means to assist in the transfer operation.
15. A mechanism as defined in any on e of claims 1, 2 or 3 which said transfer station includes, loading platen means having a substantially planar surface including means for holding said transfer medium against said planar surface, said moving means including means for moving said loading platen means surface from a first load and unload position away from said web, to a second transfer position close to but spaced from and substantially parallel to said front side of said web, and roller means disposed adjacent said back side spaced for movement against said back side of said web parallel to said platen means surface to being said film portion into close proximity with said transfer medium for transferring an image to said medium.
16. A mechanism as defined in any one of claims 1, 2 or 3 in which said transfer station includes, loading platen means having a substantially planar surface including means for holding said transfer medium against said planar surface, said moving means including means for moving said loading platen means surface from a first load an d unload position away from said web, to a second transfer position close to but spaced from and substantially parallel to said front side of said web, roller means disposed adjacent said back side spaced for movement against said back side of said web parallel to said platen means surface to bring said film portion into close proximity with said transfer medium for transferring an image to said medium and transfer bias means for electrically biasing said film portion relative to said transfer medium and said platen means to assist in the transfer operation.
17. A mechanism as defined in any one of claims 1, and 4 further including a cleaning station following said transfer station including means for cleansing any excess toner or other material form said web and said film portion.
18. A mechanism as defined in claim 1 in which said transfer station includes, transfer bias means for electrically biasing said film portion relative to said transfer medium to assist in the transfer operation,
19. A method for reproducing an image onto a transfer medium from an electrophotographic film portion of an endless web comprising, forming said endless web into substantially parallel upper and lower planar reaches rotating said web sequentially through a series of stations positioned along the reaches, charging said film portion in a charging station, locating and stopping said film portion against a planar surface in an exposure station at the lower planar reach, exposing the electrophotographic portion of said lower planar reach, defining a toning gap by spacing the toner application a uniform distance from said film portion as it passes through said toning, the applicator having a smooth toning surface extending transverse and parallel to and spaced from said lower planar reach, feeding liquid toner to said film portion thereat, applying a substantially constant amount of liquid toner across the width of only the bottom side of said film portion in a toning station located downstream of the exposure station, and transferring an image from said film portion to a transfer medium in a transfer station located downstream of the toning station.
20. A method for reproducing as defined in claim 19 in which said toning includes, rolling said liquid toner into close proximity with said film portion.
21. A method for reproducing as defined in any one of claims 19 or 20 in which said toning includes, electrically biasing said surface relative to said film portion.
22. A method for reproducing as defined in any one of claims 19 or 20 in which said transferring includes, feeding said transfer medium close to but spaced from said web, and moving said transfer medium into close proximity with said film portion as it passes through said transfer station.
23. A method for reproducing as defined in any one of claims 19 or 20 in which said transferring includes, holding said transfer medium against a planar surface, forming a planar reach from said film portion as it passes through said transfer station, moving said transfer medium parallel to said planar reach, stopping said film portion in said planar reach, and sequentially moving said film portion into close proximity with said transfer medium.
24. A method for reproducing as defined in any one of claims 19 or 20 including cleaning said film portion in a cleaning station after it has passed through said transfer station.
25. A method for reproducing as defined in any one of claims 19 or 20 in which said transferring includes, electrically biasing said transfer medium relative to said film portion.
26. A method for reproducing as defined any any one of claims 19 or 20 in which said toning includes, applying a liquid toner in a smooth and nonturbulent flow to said film portion,
27. A method for reproducing as defined in any one of claims 19 or 20 including applying a positive pressure against said web in said exposure station to push said web away from said planar surface as it rotates through said exposure station.
CLAIMS SUPPORTED BY THE
SUPPLEMENTARY DISCLOSURE
CLAIMS SUPPORTED BY THE
SUPPLEMENTARY DISCLOSURE
28. An attachment for an optical projecting system for use in making a copy of a document on a sheet of carrier material comprising:
rotatable endless web means mounted on rollers and having a first planar reach and including at least a portion which is electrophotographic in character, said web and film portion including a front or exposure side and a back side;
drive means for rotating said web sequentially through a set of stations;
said set of stations including;
a charging station located adjacent said front side including corona means for charging said electrophotographic portion while it is in said charging station;
an exposure station following said charging for exposing said electrophotographic portion when said electrophotographic portion is at the first planar reach and forming thereby a latent image of the document;
a toning station following said exposure station including means to apply a constant amount of toner to the exposed electrophotographic portion for toning the latent image as it is moved through said toning station; and a transfer station following said toning station including means for transferring the toned image from said electrophotographic portion onto a sheet of carrier material, including means for moving said sheet of carrier material and said front side of said electrophotographic portion into close proximity during said transfer.
rotatable endless web means mounted on rollers and having a first planar reach and including at least a portion which is electrophotographic in character, said web and film portion including a front or exposure side and a back side;
drive means for rotating said web sequentially through a set of stations;
said set of stations including;
a charging station located adjacent said front side including corona means for charging said electrophotographic portion while it is in said charging station;
an exposure station following said charging for exposing said electrophotographic portion when said electrophotographic portion is at the first planar reach and forming thereby a latent image of the document;
a toning station following said exposure station including means to apply a constant amount of toner to the exposed electrophotographic portion for toning the latent image as it is moved through said toning station; and a transfer station following said toning station including means for transferring the toned image from said electrophotographic portion onto a sheet of carrier material, including means for moving said sheet of carrier material and said front side of said electrophotographic portion into close proximity during said transfer.
29. An attachment as defined in claim 28 wherein said toning station includes:
a supply of liquid toner means for applying said toner in a smooth and nonturbulent flow to said front side of said electrophotographic portion.
a supply of liquid toner means for applying said toner in a smooth and nonturbulent flow to said front side of said electrophotographic portion.
30. An attachment as defined in claim 28 wherein said toning station includes:
toning platen means including a smooth substantially planar surface spaced from said front side; and manifold means having at least a first longitudinal baffle connected to a longitudinal exit for flowing said toner onto said electrophotographic portion.
toning platen means including a smooth substantially planar surface spaced from said front side; and manifold means having at least a first longitudinal baffle connected to a longitudinal exit for flowing said toner onto said electrophotographic portion.
31. An attachment as defined in claim 30 wherein said smooth substantially planar surface of the toning platen is arcuate shaped and is provided with a central slot.
32. An attachment as defined in claim 31 wherein said toning station includes;
bias means for electrically biasing said electrophotographic portion relative to said toning platen means across said gap to assist in the toning operation.
bias means for electrically biasing said electrophotographic portion relative to said toning platen means across said gap to assist in the toning operation.
33. An attachment as defined in claim 31 wherein said arcuate surface of the toning platen is made of conductive material.
34. An attachment as defined in claim 30 and wherein said toning station includes a reservoir containing a liquid toner and rotatably mounted feed roller for transporting liquid toner from the reservoir to the electrophotographic portion.
35. An attachment as defined in claim 28 and wherein said toner station includes:
toner feed roll means disposed adjacent to said front side for feeding toner to said electrophotographic portion; and toning platen means adjacent said feed roll means and said film portion including a smooth substantially planar surface spaced from said front side.
toner feed roll means disposed adjacent to said front side for feeding toner to said electrophotographic portion; and toning platen means adjacent said feed roll means and said film portion including a smooth substantially planar surface spaced from said front side.
36. An attachment as defined in claim 35 wherein said toner station includes:
bias means for electrically biasing said electrophotographic portion relative to said toning platen means across the space between them to assist in the toning operation,
bias means for electrically biasing said electrophotographic portion relative to said toning platen means across the space between them to assist in the toning operation,
37. An attachment as defined in claim 28 and wherein said toning station includes a container, a quantity of liquid toner in said container, and a feed roller for transporting liquid toner from the container to the electrophotographic portion, the container having a top wall which is made of conductive material and which functions as a toning platen.
38. A mechanism as defined in claim 28 wherein said toning station includes:
toning platen means including a smooth arcuate planar surface disposed proximate a roller for supporting the web.
toning platen means including a smooth arcuate planar surface disposed proximate a roller for supporting the web.
39. An attachment as defined in claim 28 wherein said transfer station includes:
support roll means disposed against said back side for supporting and positioning said web and film portion as it passes through said transfer station;
chute means for feeding said carrier material adjacent to but spaced from said web on said front side; and transfer roll means opposite said support roll means being operative by said moving means to press against said carrier material to move it into close proximity with said electrophotographic portion for transferring an image to said carrier material as it passes through said transfer station between said rolls.
support roll means disposed against said back side for supporting and positioning said web and film portion as it passes through said transfer station;
chute means for feeding said carrier material adjacent to but spaced from said web on said front side; and transfer roll means opposite said support roll means being operative by said moving means to press against said carrier material to move it into close proximity with said electrophotographic portion for transferring an image to said carrier material as it passes through said transfer station between said rolls.
40. An attachment as defined in claim 39 wherein said transfer station includes:
transfer bias means for electrically biasing said electrophotographic portion relative to said carrier material and said transfer roll means to assist in the transfer operation.
transfer bias means for electrically biasing said electrophotographic portion relative to said carrier material and said transfer roll means to assist in the transfer operation.
41. An attachment as defined in claim 37 wherein the feed roller is mechanically coupled to the roller arranged to support and rotate the web.
42. An attachment for use with an optical projection system for use in making a copy of a document electrophotographically comprising:
roller mounted endless web means including at least a portion that is electrophotographic in character, said web and film portion including a front or exposure side and a back side and being arranged to define first and second substantially parallel planar reaches;
drive means for rotating said web sequentially through a set of station;
said set of stations including;
a charging station with corona means for charging said film portion;
an exposure station following said charging station for producing a latent image on said film portion;
a toning station following said exposure station including a toner application means for applying a substantially constant amount of liquid toner across the width of only said front side of said imaged electrophotographic portion as it is moved through said toner station to produce a toned image on said film portion, said toner application means defining a uniform toning gap; and a transfer station following said toning station including means for transferring said toner imaged from said electrophotographic portion onto a transfer medium, including means for moving said transfer medium and said front side of said toned electrophotographic portion into close proximity during said transfer.
roller mounted endless web means including at least a portion that is electrophotographic in character, said web and film portion including a front or exposure side and a back side and being arranged to define first and second substantially parallel planar reaches;
drive means for rotating said web sequentially through a set of station;
said set of stations including;
a charging station with corona means for charging said film portion;
an exposure station following said charging station for producing a latent image on said film portion;
a toning station following said exposure station including a toner application means for applying a substantially constant amount of liquid toner across the width of only said front side of said imaged electrophotographic portion as it is moved through said toner station to produce a toned image on said film portion, said toner application means defining a uniform toning gap; and a transfer station following said toning station including means for transferring said toner imaged from said electrophotographic portion onto a transfer medium, including means for moving said transfer medium and said front side of said toned electrophotographic portion into close proximity during said transfer.
43. An attachment as defined in claim 42 wherein said toning station includes:
a supply of liquid toner wherein said liquid toner is applied by said toner application means in a smooth and nonturbulent flow to said front side of said imaged electrophotographic portion.
a supply of liquid toner wherein said liquid toner is applied by said toner application means in a smooth and nonturbulent flow to said front side of said imaged electrophotographic portion.
44. An attachment as defined in claim 42 wherein said toner applying means includes manifold means having at least a first longitudinal baffle connected to a longitudinal exit for flowing said liquid toner onto said imaged electrophotographic portion.
45. An attachment as defined in claim 44 wherein said toning station includes:
bias means for electrically biasing said electrophotographic portion relative to said toning platen means across said gap to assist in the toning operation.
bias means for electrically biasing said electrophotographic portion relative to said toning platen means across said gap to assist in the toning operation.
46. An attachment as defined in claim 42 wherein said toner application means includes:
toner feed roll means disposed substantially parallel to and adjacent to said front side for feeding toner to said imaged electrophotographic portion.
toner feed roll means disposed substantially parallel to and adjacent to said front side for feeding toner to said imaged electrophotographic portion.
47. An attachment as defined in claim 42 wherein said toner station includes:
bias means for electrically biasing said imaged electrophotographic portion relative to said toning platen means across the space between them to assist in the toning station.
bias means for electrically biasing said imaged electrophotographic portion relative to said toning platen means across the space between them to assist in the toning station.
48. An attachment as defined in claim 42 wherein said transfer station includes:
support means disposed against said back side for supporting and positioning said web as it passes through said transfer station;
chute means for feeding carrier material adjacent to but spaced from said web on said front side; and transfer roll means opposite said support roll means being operative by said moving means to press against said medium to move it into close proximity with said toned portion for transferring said toned image to said carrier material as it passes through said transfer station between said rolls.
support means disposed against said back side for supporting and positioning said web as it passes through said transfer station;
chute means for feeding carrier material adjacent to but spaced from said web on said front side; and transfer roll means opposite said support roll means being operative by said moving means to press against said medium to move it into close proximity with said toned portion for transferring said toned image to said carrier material as it passes through said transfer station between said rolls.
49. An attachment as defined in claim 48 wherein said transfer station includes:
transfer bias means for electrically biasing said toned portion relative said carrier material and said transfer roll means to assist in the transfer operations.
transfer bias means for electrically biasing said toned portion relative said carrier material and said transfer roll means to assist in the transfer operations.
50, A method for reproducing an image onto a sheet of carrier material electrophotographically using an endless web mounted on rollers and having an electrophotographic portion including:
charging said film portion;
locating and stopping said electrophotographic portion along a planar reach of the web;
exposing the film portion to a light image at the planar reach;
applying a substantially constant amount of liquid toner across the width of only the bottom side of said film portion in a toning station; and transferring an image from said portion to a sheet of carrier material in a transfer station.
charging said film portion;
locating and stopping said electrophotographic portion along a planar reach of the web;
exposing the film portion to a light image at the planar reach;
applying a substantially constant amount of liquid toner across the width of only the bottom side of said film portion in a toning station; and transferring an image from said portion to a sheet of carrier material in a transfer station.
51. A method as defined in claim 50 where said toning includes:
applying the liquid toner in a smooth and nonturbulent flow to said portion,
applying the liquid toner in a smooth and nonturbulent flow to said portion,
52. A method as defined in claim 51 wherein said toning includes;
electrically biasing said surface relative to said film portion.
electrically biasing said surface relative to said film portion.
53. A method as defined in claim 52 wherein said toning includes:
rolling said toner into close proximity with said portion.
rolling said toner into close proximity with said portion.
54. A method as defined in claim 53 wherein said toning includes:
forming a smooth arcuate planar reach from said portion of the web as it passes through said toning station; and placing a smooth arcuate planar toning surface parallel to and spaced from said reach.
forming a smooth arcuate planar reach from said portion of the web as it passes through said toning station; and placing a smooth arcuate planar toning surface parallel to and spaced from said reach.
55. A method as defined in claim 54 wherein said toning includes:
electrically biasing said surface relative to said portion.
electrically biasing said surface relative to said portion.
56. A method as defined in claim 48 wherein said transferring includes:
feeding said transfer medium close to but spaced from said web; and moving said sheet of carrier material into close proximity with said portion as it passes through said transfer station.
feeding said transfer medium close to but spaced from said web; and moving said sheet of carrier material into close proximity with said portion as it passes through said transfer station.
57. A method as defined in claim 56 wherein said transferring includes:
electrically biasing said carrier material relative to said electrophotographic portion.
electrically biasing said carrier material relative to said electrophotographic portion.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US80257377A | 1977-06-01 | 1977-06-01 | |
| US802,573 | 1977-06-01 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1133571A true CA1133571A (en) | 1982-10-12 |
Family
ID=25184086
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA304,495A Expired CA1133571A (en) | 1977-06-01 | 1978-05-31 | Offset plate image transfer attachment for graphic art cameras |
Country Status (9)
| Country | Link |
|---|---|
| JP (1) | JPS542125A (en) |
| BE (1) | BE867659A (en) |
| CA (1) | CA1133571A (en) |
| CH (1) | CH622365A5 (en) |
| DE (1) | DE2823839A1 (en) |
| FR (1) | FR2393351A1 (en) |
| GB (1) | GB1573397A (en) |
| IT (1) | IT1105318B (en) |
| NL (1) | NL7805922A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4259005A (en) * | 1978-12-01 | 1981-03-31 | Coulter Systems Corporation | Device and method for developing latent electrostatic images |
| MX146428A (en) * | 1979-02-12 | 1982-06-25 | Coulter Systems Corp | ELECTROPHOTOGRAPHIC COPIER MACHINE WITH REDUCED PROFILE |
| AU543266B2 (en) * | 1980-06-25 | 1985-04-18 | Stork Colorproofing B.V. | Liquid toner applicator |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3730708A (en) * | 1968-02-08 | 1973-05-01 | Xerox Corp | Electrophotographic multi-color process employing liquid developer |
| US3836245A (en) * | 1972-11-29 | 1974-09-17 | Savin Business Machines Corp | Copy machine having photoconductive belt |
-
1978
- 1978-05-31 DE DE19782823839 patent/DE2823839A1/en not_active Ceased
- 1978-05-31 CH CH593978A patent/CH622365A5/en not_active IP Right Cessation
- 1978-05-31 NL NL7805922A patent/NL7805922A/en not_active Application Discontinuation
- 1978-05-31 GB GB25475/78A patent/GB1573397A/en not_active Expired
- 1978-05-31 JP JP6444478A patent/JPS542125A/en active Pending
- 1978-05-31 FR FR7816265A patent/FR2393351A1/en not_active Withdrawn
- 1978-05-31 BE BE188194A patent/BE867659A/en not_active IP Right Cessation
- 1978-05-31 CA CA304,495A patent/CA1133571A/en not_active Expired
- 1978-05-31 IT IT49622/78A patent/IT1105318B/en active
Also Published As
| Publication number | Publication date |
|---|---|
| FR2393351A1 (en) | 1978-12-29 |
| BE867659A (en) | 1978-11-30 |
| NL7805922A (en) | 1978-12-05 |
| GB1573397A (en) | 1980-08-20 |
| IT7849622A0 (en) | 1978-05-31 |
| DE2823839A1 (en) | 1978-12-21 |
| JPS542125A (en) | 1979-01-09 |
| CH622365A5 (en) | 1981-03-31 |
| IT1105318B (en) | 1985-10-28 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |