CA1133572A - Plate making attachment for graphic art cameras - Google Patents
Plate making attachment for graphic art camerasInfo
- Publication number
- CA1133572A CA1133572A CA304,496A CA304496A CA1133572A CA 1133572 A CA1133572 A CA 1133572A CA 304496 A CA304496 A CA 304496A CA 1133572 A CA1133572 A CA 1133572A
- Authority
- CA
- Canada
- Prior art keywords
- reach
- film portion
- belt
- attachment
- toner
- 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
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
- G03G15/22—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
Plate making attachment for a graphic art camera taking the place of the ordinary silver halide film cartridge back.
The attachment includes an endless belt of flexible electro-photographic film that is charged by a source of corona, exposed, rotated to a location where toner in liquid form is applied to the resulting latent image under bias conditions.
A supply of plate material such as paper, aluminum, plastic or other flexible substrate material is included and a single sheet or a portion of a continuous supply roll is fed into the nip of a pressure roller engaging against the endless belt, transferring the toned image and dispensing it or feeding it past a fixing station and thereafter dispensing the completed plate. This plate is suitable for use in an offset printing press.
Plate making attachment for a graphic art camera taking the place of the ordinary silver halide film cartridge back.
The attachment includes an endless belt of flexible electro-photographic film that is charged by a source of corona, exposed, rotated to a location where toner in liquid form is applied to the resulting latent image under bias conditions.
A supply of plate material such as paper, aluminum, plastic or other flexible substrate material is included and a single sheet or a portion of a continuous supply roll is fed into the nip of a pressure roller engaging against the endless belt, transferring the toned image and dispensing it or feeding it past a fixing station and thereafter dispensing the completed plate. This plate is suitable for use in an offset printing press.
Description
1~ 3 ~5 ~
The field of this invention is the art of making offset printing plates for use in printing through the use of electrophotographic techniques.
Offset plates are made photographically by complex methods requiring the use of silver halide film, photoresists, an~ the processing of the images to achieve their incorporation onto plates that can be used in 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 not much of this type of technique is used.
The invention herein revolves around a type of electrophotographic film that is capable of bein~ imaged with quality and grey scale as good as if not better than that achieved by photographic techniques and with resolution that is better. The film comprises an inorganic coating of microcrystalline material that is bonded onto a polyester substrate with an intervening ohmic layer to aid in charging.
The material which is used comprises a coating of radio frequency sputtered cadmium sulfide that is from about 2000 Angstroms to about 2 microns thick upon a layer of about 300 to 500 Angstroms thick of indium tin oxide which in turn is bonded to a sheet of stable polyester plastic about .005 inch thick. One such film is described in U.S. Patent ~o.
4,025,339 issued May 24, 1977.
Because of the fact that the film can be exposed at high speed and transferred immediately to a carrier such as paper, aluminum, plastic and the like, the entire process ~ ~33~gi~
can be carried on inside of a cartridge that takes the i place of the usual photographic film cartridge that is used ¦ with graphic arts cameras. This is convenient and eliminates considerable processing since the complete plate emerges from 1 5 the device, can be immersed in a suitable bath which renders the toned ~nd untoned parts of the image ink receptive ana ink repellant, respectively, and then utilized in an offset printing press.
The disadvantages of the previous proposals may be over-come by replacing the silver halide film cartridge of a graphic art camera with a plate making attachment having an endless belt of electrophotographic film and a supply of plate material on the interior thereof. The film is char~ed and then exposed in a first reach to form an image thereon and then rotated to a second reach where toner is applied to the image. The film is then rotated through a nip with a plate material to trans~er the image to the plate material which is then dispensed from the attachment or first fed through a fixing station if it is desired to complete the plate internally of the attachment.
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., . , . . , .. , , ~. ,, ~ - , . . : , : .: :
~: . .: . ~ , ~13 'S ~';2 The pre~erred embodiments of this invention will now be described, by way of example, with reference to the drawings accompanying this specification in which:
Figure 1 is a block diagram showing how the attachment of the invention is connected to the back of a graphic arts camera and Figure 2 is a diagram of the attachment showing the basic parts and construction thereof.
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 thereo~
Figure 1 illustrates such a camera at 10 with a lens system that can partlally be seen at 12 and having the normal cartridge replaced by the attachment of the invention as shown at 14. The completed plate as dispensed from the attachment 16 is shown at 18 On its interior, the attachment 16 is shown to contain an endless electrophotographic film belt 20 with drive and/or mounting rollers at 22 and 24. A drive roller 26 may be utilized in addition to the mounting rollers. The bottom reach 28 of the belt 20 is shown facing the optical system of the camera, represented by the lens 30, so that when the camera is used to image copy, the image will be projected onto the outer surface of the belt on the bottom thereof. The attachment also contains a toner and bias belt 32, a supply of plate material ,; .
. . . -S,,~
at 34 mounted on a suitable support 36, toner supply and dispensing means at 38, a pressure roller 40 and an op-tical fixing station at 42. Various guide and drive rollers, controls, electrical connections and the like are required but not shown since, as will be explained, when the invention is described these will become apparent to those skilled in this art.
There is a corona voltage source and a corona wire mounting at 44 which may be fixed or oscillating to provide an even distribution of charge when the attachment is in operation.
When it is desired to use the camera 10 and the attachment 16, the camera is focussed on the copy, the copy is suitably illuminated and the cycle of operation is started by any suitable switch. The sequence of operation ls readily programmed by switching and logic circuits that are readily constructed and incorporated into the attachment.
The first thing that happens is that the belt 20 is driven in~a generally clockwise direction by the drive roller ~6 or other drive means for a period of time that is required to carry a portion of the length thereof past the corona device 44 and onto the bottom of the belt to form the reach 28 along substantially the entire length thereof. The corona device 44 has in the meantime been energized and it charges the photoconductive coating of the film forming the belt 20.
The direction of movement is shown by the arrows.
Ideally the charge of the belt 20 is controlled by suitably controlling the corona voltage and/or the speed of the belt 20. The surface voltage may be measured by an electrostatic voltmeter and related to the amount of exposure .".; , ~ . , . ......... , --` ~13~572 :`
that is to be made.
Once the charged length of the film of the belt 20 has been positioned to form the reach 28, the belt is stopped in its movement and rigidly held at the specific location wi-th respect to the focal plane of the camera 10 by means of a platen 46. The platen 46 may be pressed against the film or may be provided with vacuum means,. Suitable means to operate the platen are provided and are not shown. The vacuum platen ~6 sucks the film reach 28 flatly against itself and holds it ~here until the exposure has been made. This, like the other unctions of the attachment 16 can be worked into an automatic program or can be performed in a sequence manually by the operator.
With the belt fixed, the camera shutter is now operated to expose the film reach 28 to the projected light image of the copy being reproduced. It is understood that the entire attachment 16 is in darkness.
After exposure the belt is released from the platen 46 by applying air pressure thereto and the belt drive operated by the roller 26 to move the belt 20 in the same clockwise direction for a period of time which will carry the now-exposed bottom section up and onto the top of the belt at the reach 48.
Here the belt stops moving once more.
~ow the toning and bias belt 32 is started up and rotates in a clockwise direction also, shown by the arrows. This movement is relatively rapid in order to dispense toner particles in a liquid form onto the upper reach 48 of the belt 20. Suitable dams and absorbant confining members are provided to prevent the toner from running off the edges and ends of `'`J ~ :
.
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the areas which it is desired to tone. Toner is dispensed from a supply which is shown at 38. The belt 32 is formed of conductive material such as metal and a bias of about 2-20 volts ~.c. plus is established between the two belts in the gap between them by a bias circuit 33, the film belt ~0 being positive relative the toning belt, After a period of tim~
has elapsed when there has been sufficient adherence of the toner particles, there is a voltage appliea to the two belts across the gap of the order of negative 200 ~olts d.c. on the toner belt relative to the film belt 20 so that there is a sweeping of the uncommitted toner particles from the toned image.
The gap between the belts is of the order of capillary dimensions to enable the handling of the liquia toner. The belt 32 is s~ueegeed dry by a suitable doctor blade 50 located at the left end thereof as viewed in Figure 2.
After the image on the belt 20 has been toned, that is, developed, the belt commences to move again, this time carrying the image to the right and into the nip between the rollers 24 and 40. In the meantime the plate material 34 which can be metal, paper or plastic, has been led through the feed rollers 52 also to the nip as indicated at 54 and is being pressed against or brought into close proximity with the surface of the belt 20 as the belt rotates. The toned image which is still moist is transferred to the plate material and emerges at the right as shown at 56. Suitable guide and confining means ensure this movement.
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There will preferably be a transfer voltage of approximately negative 400 volts d.c. applied to the trans~er roller 40 to move the toner image onto the carrier material.
After the transferred carrier material emerges ~rom the transfer means at 56 the image may be ejected or may pass over a fixing station of heat lamps or the like at 42 where the toner is fused to the carrier. This completes the making of the plate which emerges at 18 from the attachment 16. The only thing left to be done to it is to render the tone~ image ink receptive and the untoned portions ink repellant. This is a technique which has been achieved by applying suitable chromate compounds or the like thereto, but this i9 not considered a part of this invention.
The plate material 34 is preferably in the form of a ~ontinUoUs strip and means are in such case provided to cut off the portion which has been processed as it emerges at 18.
Such cutoff means are indicated generally by the block 58.
The belt 20 may also be an endless webb containing only a portion of film substantially equal to the reach 28. The fixing of the toner may be done outside of the attachment. The corona device 44 may be energiæed after the belt is stopped in the reach 28 and the device 44 may be moved past the stopped film to apply the charge.
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~335f~2 1 Throughout, copies oE subject matter are made electrophotographically by a technique which requires that an image be formed of the subject matter that is to be reproduced. The image is formed by using some type of optical projecting system.
The camera previously described in respect of the original disclosure functions in the manner of a projector ' with the shutter thereof acting as a switch to turn on a light source for exposure and shut off the light source for toning.
It should be understood that the foregoing specification describes an attachment which may be employed without the imaging platen 46 where the product is not intended for use as a printing plate.
In respect of such usage, it is not necessary to bring and to hold the lower reach 28 of belt 20 into the exact image plane of the lens system 12. Thus the image platen 46 need not be provided.
'~' ~335~J'~
Figure 3 is a simplified representation of another emb-odiment of the attachment of the invention connected to an optical projection system; and Figure 4 is a schematic representation of the attachment in Figure 3 showing the basic parts and construction thereof.
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1 In Figures 3 and 4 there is illustrated another embodiment of the invention.
There is an optical projecting system identified by reference numeral 110. Optical projecting system 110 includes a housing 111, a lens system 112 for projecting an image of the subject matter D to be copied, a platen assembly 113 including a copy platen CP and a platen cover PC for holding subject matter D and a pair of lights L
and L2 for illuminating subject matter D. Lens system 112 includes a pair of mirrors Ml andf M2 and a lens L. An attachment 114 constructed according to this invention is connected to housing 111 by brackets 116. Attachment 114 includes a housing 117 having an opening 118.
On its interior, attachment 114 is shown to contain an electrophotographic belt 120 mounted on rollers 122 and 124. A guide and aligning roller 127 is suitably positioned underneath belt 120. Belt 120 has a bottom planar reach 128 disposed in the image plane of lens system 112 such that when the optical projecting system 111 is used to image subject matter D, the image will be projected onto the outer surface of belt 120 on the bottom thereof.
; Attachment 114 also includes a toning station 131 at which is located a toning deYice 132. The toning device 132 includes a suitably mounted well 134 having a supply of liquid toner. Attachement 114 also includes a transfer station 135 which includes a pivotally mounted transfer roller 136 and a holder 139 for a supply S of carrier material.
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Various controls, electrical connections and the like are also required but not shown.
Thare is a charging station 143 containing a corona gener-ating device 144 including a corona wire which may be fixed or oscillating.
When it is desired to use optical projection system 110 and attachment 114, the subject matter D to be copied is placed face down on the copy platen CP, the ~platen cover ~C closed and the cycle of operation started by any suitable means. The seq-uence of operation is readily programmed by switching and logic circuits tnot shown) that are readily constructed and incorporated into attachment 114.
The first thing that happens is that corona generating device 144 is energized and belt 120 is driven in a clockwise direction by rollers 122 and 124 for a period of time necessary to carry a portion of the length thereof past corona generating device 144.
Once the charged portion of belt 120 has been positioned at planar reach 128, belt 120 is stopped, lights Ll and L2 turned on and the charged portion of belt 120 exposed to the pro-jected image of subject matter D for a period of time sufficient to form a latent image thereon.
After exposure, the charged portion of belt 120 containing the latent image is moved through toning station 131 where it is toned or developed with a liquid toner from well 134 as it passes through.
The portion of belt 120 containing the toned image is then advanced to the transfer station 135 and into the nip between -~33~ 1~
rollers 124 and 126. At the same time a sheet of carrier mat-erial from holder 139 is also fed into the nip between rollers 124 and 126 causing the toned image which is still moist to be transfered from belt 120 to the sheet of carrier material. The sheer of carrier material containing the toned i~mage emerges from attachment 114 at opening 118 where it is dropped into a tray 152.
The field of this invention is the art of making offset printing plates for use in printing through the use of electrophotographic techniques.
Offset plates are made photographically by complex methods requiring the use of silver halide film, photoresists, an~ the processing of the images to achieve their incorporation onto plates that can be used in 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 not much of this type of technique is used.
The invention herein revolves around a type of electrophotographic film that is capable of bein~ imaged with quality and grey scale as good as if not better than that achieved by photographic techniques and with resolution that is better. The film comprises an inorganic coating of microcrystalline material that is bonded onto a polyester substrate with an intervening ohmic layer to aid in charging.
The material which is used comprises a coating of radio frequency sputtered cadmium sulfide that is from about 2000 Angstroms to about 2 microns thick upon a layer of about 300 to 500 Angstroms thick of indium tin oxide which in turn is bonded to a sheet of stable polyester plastic about .005 inch thick. One such film is described in U.S. Patent ~o.
4,025,339 issued May 24, 1977.
Because of the fact that the film can be exposed at high speed and transferred immediately to a carrier such as paper, aluminum, plastic and the like, the entire process ~ ~33~gi~
can be carried on inside of a cartridge that takes the i place of the usual photographic film cartridge that is used ¦ with graphic arts cameras. This is convenient and eliminates considerable processing since the complete plate emerges from 1 5 the device, can be immersed in a suitable bath which renders the toned ~nd untoned parts of the image ink receptive ana ink repellant, respectively, and then utilized in an offset printing press.
The disadvantages of the previous proposals may be over-come by replacing the silver halide film cartridge of a graphic art camera with a plate making attachment having an endless belt of electrophotographic film and a supply of plate material on the interior thereof. The film is char~ed and then exposed in a first reach to form an image thereon and then rotated to a second reach where toner is applied to the image. The film is then rotated through a nip with a plate material to trans~er the image to the plate material which is then dispensed from the attachment or first fed through a fixing station if it is desired to complete the plate internally of the attachment.
.
., . , . . , .. , , ~. ,, ~ - , . . : , : .: :
~: . .: . ~ , ~13 'S ~';2 The pre~erred embodiments of this invention will now be described, by way of example, with reference to the drawings accompanying this specification in which:
Figure 1 is a block diagram showing how the attachment of the invention is connected to the back of a graphic arts camera and Figure 2 is a diagram of the attachment showing the basic parts and construction thereof.
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 thereo~
Figure 1 illustrates such a camera at 10 with a lens system that can partlally be seen at 12 and having the normal cartridge replaced by the attachment of the invention as shown at 14. The completed plate as dispensed from the attachment 16 is shown at 18 On its interior, the attachment 16 is shown to contain an endless electrophotographic film belt 20 with drive and/or mounting rollers at 22 and 24. A drive roller 26 may be utilized in addition to the mounting rollers. The bottom reach 28 of the belt 20 is shown facing the optical system of the camera, represented by the lens 30, so that when the camera is used to image copy, the image will be projected onto the outer surface of the belt on the bottom thereof. The attachment also contains a toner and bias belt 32, a supply of plate material ,; .
. . . -S,,~
at 34 mounted on a suitable support 36, toner supply and dispensing means at 38, a pressure roller 40 and an op-tical fixing station at 42. Various guide and drive rollers, controls, electrical connections and the like are required but not shown since, as will be explained, when the invention is described these will become apparent to those skilled in this art.
There is a corona voltage source and a corona wire mounting at 44 which may be fixed or oscillating to provide an even distribution of charge when the attachment is in operation.
When it is desired to use the camera 10 and the attachment 16, the camera is focussed on the copy, the copy is suitably illuminated and the cycle of operation is started by any suitable switch. The sequence of operation ls readily programmed by switching and logic circuits that are readily constructed and incorporated into the attachment.
The first thing that happens is that the belt 20 is driven in~a generally clockwise direction by the drive roller ~6 or other drive means for a period of time that is required to carry a portion of the length thereof past the corona device 44 and onto the bottom of the belt to form the reach 28 along substantially the entire length thereof. The corona device 44 has in the meantime been energized and it charges the photoconductive coating of the film forming the belt 20.
The direction of movement is shown by the arrows.
Ideally the charge of the belt 20 is controlled by suitably controlling the corona voltage and/or the speed of the belt 20. The surface voltage may be measured by an electrostatic voltmeter and related to the amount of exposure .".; , ~ . , . ......... , --` ~13~572 :`
that is to be made.
Once the charged length of the film of the belt 20 has been positioned to form the reach 28, the belt is stopped in its movement and rigidly held at the specific location wi-th respect to the focal plane of the camera 10 by means of a platen 46. The platen 46 may be pressed against the film or may be provided with vacuum means,. Suitable means to operate the platen are provided and are not shown. The vacuum platen ~6 sucks the film reach 28 flatly against itself and holds it ~here until the exposure has been made. This, like the other unctions of the attachment 16 can be worked into an automatic program or can be performed in a sequence manually by the operator.
With the belt fixed, the camera shutter is now operated to expose the film reach 28 to the projected light image of the copy being reproduced. It is understood that the entire attachment 16 is in darkness.
After exposure the belt is released from the platen 46 by applying air pressure thereto and the belt drive operated by the roller 26 to move the belt 20 in the same clockwise direction for a period of time which will carry the now-exposed bottom section up and onto the top of the belt at the reach 48.
Here the belt stops moving once more.
~ow the toning and bias belt 32 is started up and rotates in a clockwise direction also, shown by the arrows. This movement is relatively rapid in order to dispense toner particles in a liquid form onto the upper reach 48 of the belt 20. Suitable dams and absorbant confining members are provided to prevent the toner from running off the edges and ends of `'`J ~ :
.
~ ~ 3~
the areas which it is desired to tone. Toner is dispensed from a supply which is shown at 38. The belt 32 is formed of conductive material such as metal and a bias of about 2-20 volts ~.c. plus is established between the two belts in the gap between them by a bias circuit 33, the film belt ~0 being positive relative the toning belt, After a period of tim~
has elapsed when there has been sufficient adherence of the toner particles, there is a voltage appliea to the two belts across the gap of the order of negative 200 ~olts d.c. on the toner belt relative to the film belt 20 so that there is a sweeping of the uncommitted toner particles from the toned image.
The gap between the belts is of the order of capillary dimensions to enable the handling of the liquia toner. The belt 32 is s~ueegeed dry by a suitable doctor blade 50 located at the left end thereof as viewed in Figure 2.
After the image on the belt 20 has been toned, that is, developed, the belt commences to move again, this time carrying the image to the right and into the nip between the rollers 24 and 40. In the meantime the plate material 34 which can be metal, paper or plastic, has been led through the feed rollers 52 also to the nip as indicated at 54 and is being pressed against or brought into close proximity with the surface of the belt 20 as the belt rotates. The toned image which is still moist is transferred to the plate material and emerges at the right as shown at 56. Suitable guide and confining means ensure this movement.
. . ... . . . . . .
. . .
, , ~
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There will preferably be a transfer voltage of approximately negative 400 volts d.c. applied to the trans~er roller 40 to move the toner image onto the carrier material.
After the transferred carrier material emerges ~rom the transfer means at 56 the image may be ejected or may pass over a fixing station of heat lamps or the like at 42 where the toner is fused to the carrier. This completes the making of the plate which emerges at 18 from the attachment 16. The only thing left to be done to it is to render the tone~ image ink receptive and the untoned portions ink repellant. This is a technique which has been achieved by applying suitable chromate compounds or the like thereto, but this i9 not considered a part of this invention.
The plate material 34 is preferably in the form of a ~ontinUoUs strip and means are in such case provided to cut off the portion which has been processed as it emerges at 18.
Such cutoff means are indicated generally by the block 58.
The belt 20 may also be an endless webb containing only a portion of film substantially equal to the reach 28. The fixing of the toner may be done outside of the attachment. The corona device 44 may be energiæed after the belt is stopped in the reach 28 and the device 44 may be moved past the stopped film to apply the charge.
. - ~
~335f~2 1 Throughout, copies oE subject matter are made electrophotographically by a technique which requires that an image be formed of the subject matter that is to be reproduced. The image is formed by using some type of optical projecting system.
The camera previously described in respect of the original disclosure functions in the manner of a projector ' with the shutter thereof acting as a switch to turn on a light source for exposure and shut off the light source for toning.
It should be understood that the foregoing specification describes an attachment which may be employed without the imaging platen 46 where the product is not intended for use as a printing plate.
In respect of such usage, it is not necessary to bring and to hold the lower reach 28 of belt 20 into the exact image plane of the lens system 12. Thus the image platen 46 need not be provided.
'~' ~335~J'~
Figure 3 is a simplified representation of another emb-odiment of the attachment of the invention connected to an optical projection system; and Figure 4 is a schematic representation of the attachment in Figure 3 showing the basic parts and construction thereof.
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- .. ;
.. . .. ... .. . , .. .. . ~ . ...
.. ~. . - . . .. ..
J
1 In Figures 3 and 4 there is illustrated another embodiment of the invention.
There is an optical projecting system identified by reference numeral 110. Optical projecting system 110 includes a housing 111, a lens system 112 for projecting an image of the subject matter D to be copied, a platen assembly 113 including a copy platen CP and a platen cover PC for holding subject matter D and a pair of lights L
and L2 for illuminating subject matter D. Lens system 112 includes a pair of mirrors Ml andf M2 and a lens L. An attachment 114 constructed according to this invention is connected to housing 111 by brackets 116. Attachment 114 includes a housing 117 having an opening 118.
On its interior, attachment 114 is shown to contain an electrophotographic belt 120 mounted on rollers 122 and 124. A guide and aligning roller 127 is suitably positioned underneath belt 120. Belt 120 has a bottom planar reach 128 disposed in the image plane of lens system 112 such that when the optical projecting system 111 is used to image subject matter D, the image will be projected onto the outer surface of belt 120 on the bottom thereof.
; Attachment 114 also includes a toning station 131 at which is located a toning deYice 132. The toning device 132 includes a suitably mounted well 134 having a supply of liquid toner. Attachement 114 also includes a transfer station 135 which includes a pivotally mounted transfer roller 136 and a holder 139 for a supply S of carrier material.
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Various controls, electrical connections and the like are also required but not shown.
Thare is a charging station 143 containing a corona gener-ating device 144 including a corona wire which may be fixed or oscillating.
When it is desired to use optical projection system 110 and attachment 114, the subject matter D to be copied is placed face down on the copy platen CP, the ~platen cover ~C closed and the cycle of operation started by any suitable means. The seq-uence of operation is readily programmed by switching and logic circuits tnot shown) that are readily constructed and incorporated into attachment 114.
The first thing that happens is that corona generating device 144 is energized and belt 120 is driven in a clockwise direction by rollers 122 and 124 for a period of time necessary to carry a portion of the length thereof past corona generating device 144.
Once the charged portion of belt 120 has been positioned at planar reach 128, belt 120 is stopped, lights Ll and L2 turned on and the charged portion of belt 120 exposed to the pro-jected image of subject matter D for a period of time sufficient to form a latent image thereon.
After exposure, the charged portion of belt 120 containing the latent image is moved through toning station 131 where it is toned or developed with a liquid toner from well 134 as it passes through.
The portion of belt 120 containing the toned image is then advanced to the transfer station 135 and into the nip between -~33~ 1~
rollers 124 and 126. At the same time a sheet of carrier mat-erial from holder 139 is also fed into the nip between rollers 124 and 126 causing the toned image which is still moist to be transfered from belt 120 to the sheet of carrier material. The sheer of carrier material containing the toned i~mage emerges from attachment 114 at opening 118 where it is dropped into a tray 152.
Claims (40)
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An attachment adapted to be operatively coupled with an optical projecting system that includes structure for projecting a light image to an image plane and exposing such a plane to such image for reproducing purposes, said attachment comprising:
A. a rotatable endless belt including at least a portion of an electrophotographic film, the belt having a first planar reach disposed generally at a first plane and a second planar reach disposed at a second plane and proximate to said first plane juxtaposed over said first planar reach but spaced therefrom, means for controlled unidirectional rotation of the belt and positioning said film portion thereof to occupy the reaches sequentially at selected operating stations including a charging station, an exposure station located immediately downstream of said charging station to receive the light image, a toning station and a transfer station in that order;
B charging means located near the commencement of said planar reach for charging the film, said portion of said electrophotographic film being disposed parallel to said second reach while at the exposure station;
C toner supply and dispensing means at the toning station downstream of said exposure station for applying toner to the exposed film portion;
D transfer means at said transfer station downstream of said toning station and along said second reach for bringing a carrier material into close proximity with said toned film portion to transfer a toned image therefrom to said carrier material;
E means for leading the carrier material out of the attachment;
F means for immobilizing the charged film portion at said exposure station along said first planar reach accurately to fix the charged film portion in the exact image plane thereat at said first reach and to hold said film portion immobile until exposure to the light image is completed and means to release the film portion subsequent to completion of exposure to permit its subsequent toner supply and dispensing means for applying toner to the second reach of the film belt;
G transfer means for bringing a carrier material, into close proximity with said film portion to transfer a toned image to said carrier material; and H means for leading the carrier material out of the attachment.
A. a rotatable endless belt including at least a portion of an electrophotographic film, the belt having a first planar reach disposed generally at a first plane and a second planar reach disposed at a second plane and proximate to said first plane juxtaposed over said first planar reach but spaced therefrom, means for controlled unidirectional rotation of the belt and positioning said film portion thereof to occupy the reaches sequentially at selected operating stations including a charging station, an exposure station located immediately downstream of said charging station to receive the light image, a toning station and a transfer station in that order;
B charging means located near the commencement of said planar reach for charging the film, said portion of said electrophotographic film being disposed parallel to said second reach while at the exposure station;
C toner supply and dispensing means at the toning station downstream of said exposure station for applying toner to the exposed film portion;
D transfer means at said transfer station downstream of said toning station and along said second reach for bringing a carrier material into close proximity with said toned film portion to transfer a toned image therefrom to said carrier material;
E means for leading the carrier material out of the attachment;
F means for immobilizing the charged film portion at said exposure station along said first planar reach accurately to fix the charged film portion in the exact image plane thereat at said first reach and to hold said film portion immobile until exposure to the light image is completed and means to release the film portion subsequent to completion of exposure to permit its subsequent toner supply and dispensing means for applying toner to the second reach of the film belt;
G transfer means for bringing a carrier material, into close proximity with said film portion to transfer a toned image to said carrier material; and H means for leading the carrier material out of the attachment.
2. The attachment as defined in claim 1 in which the toner is in a liquid form.
3. The attachment as defined in claim 1 in which the toner dispensing means include a second belt having a top reach and a bottom reach, the toner supply being arranged to apply toner to the top reach of the second belt, the bottom reach of the second belt being juxtaposed parallel lto the second reach of the film belt and movable in a direction opposite to the direction of movement of the endless belt, the toner adapted to be carried from the top reach of the second belt around to the bottom reach thereof and thereafter dropped onto the upwardly facing film portion along the second reach so as to tone the latent image carried thereon.
4. The attachment as defined in claim 3 in which means are provided electrically to bias the belts relative to one another across the space between belts to assist in the toning operation.
5. The attachment as defined in claim 3 in which means are provided electrically to bias the belts relative to one another across the space between belts to assist in the toning operation, said bias means including structure for applying a low voltage bias at the beginning of a toning period and a higher bias at the end of such period.
6. The attachment as defined in claim 1 in which the transfer means include transfer roll means engaged against the film surface and providing a nip between itself and the film surface, a supply of said carrier material, and means for leading said carrier material into the nip as said film portion is rotated by the roll means.
7. The attachment as defined in claim 1 in which means are provided for fixing a transferred image on said carrier material before it is led out of the attachment.
8. The attachment as defined in claim 1 in which means are provided electrically to bias said carrier material relative to said film portion.
9. The attachment as defined in claim 1 in which said immobilizing means comprise a platen located parallel to said reaches and having a bottom planar portion in the image plane.
10. The attachment as defined in claim 1 in which the toner dispensing means include a second belt having a top reach and a bottom reach, the toner supply being arranged to apply toner to the top reach of the second belt, the bottom reach of the second belt being juxtaposed parallel to the second reach of the film belt and movable in a direction opposite to the direction of movement of the endless belt, the toner adapted to be carried from the top reach of the second belt around to the bottom reach thereof and thereafter dropped onto the upwardly facing film portion along the second reach so as to tone the latent image carried thereon, said immobilizing means comprising a platen located parallel to said reaches and vacuum means associated with said platen to draw said film portion flat against said bottom planar portion in the exact image plane and being releasable to permit linear translation of said film portion toward the toning station.
11. The attachment as defined in claim 1 in which the toner dispensing means include a second belt having a top reach and a bottom reach, the toner supply being arranged to apply toner to the top reach of the second belt, the bottom reach of the second belt being juxtaposed parallel to the second reach of the film belt and movable in a direction opposite to the direction of movement of the endless belt, the toner adapted to be carried from the top reach of the second belt around to the bottom reach thereof and thereafter dropped onto the upwardly facing film portion along the second reach so as to tone the latent image carried thereon and means for removing any remainent toner from the second belt as it rotates subsequent to transfer and prior to entry thereof to its top reach.
12. A method for reproducing an image onto a sheet carrier material using an electrophotographic film portion of an endless belt including:
rotating said belt unidirectionally through a series of locations spaced along a pair of closely spaced parallel reaches moving said film portion after charging to a second location along the lower one of said reaches downstream of the first location for exposing said charged film portion to the image at the second location, positioning said film portion in the exact image plane at the exposure station and holding the same thereat, exposing said charged film portion to the image at the second location while said film portion is held in the exact image plane and releasing said exposed film portion for movement, toning said film portion with a liquid toner as it passed through a third location downstream of said second location; and transferring an image from said film portion to a carrier material as it passes through a fourth location disposed downstream of the third location.
rotating said belt unidirectionally through a series of locations spaced along a pair of closely spaced parallel reaches moving said film portion after charging to a second location along the lower one of said reaches downstream of the first location for exposing said charged film portion to the image at the second location, positioning said film portion in the exact image plane at the exposure station and holding the same thereat, exposing said charged film portion to the image at the second location while said film portion is held in the exact image plane and releasing said exposed film portion for movement, toning said film portion with a liquid toner as it passed through a third location downstream of said second location; and transferring an image from said film portion to a carrier material as it passes through a fourth location disposed downstream of the third location.
13. The method as defined in claim 12 and the additional steps of stopping said film portion at said second location, immobilizing said film portion in an exposure plane at said second location and releasing said film portion upon completion of exposure.
14. The method as defined in claim 12, wherein said film portion is held in the exact image plane at the exposure station by a negative pressure applied to one side of said film.
15. The method of reproducing as defined in claim 12, 13 or 14, wherein said toning includes the step of applying an electrical bias during toning.
16. The method of reproducing as defined in claim 12, 13 or 14 wherein said transferring includes: electrically biasing said carrier material relative to the toned film portion during transfer.
17. The method of reproducing as defined in claim 12, 13 or 14 in which said toning includes the steps of forming a planar reach in said third location, stopping said film portion in said planar reach, and applying toner to the top of a second belt rotation with a bottom reach substantially parallel to and spaced from said planar reach to dispense said toner onto said film portion.
18. The method of reproducing as defined in claim 12, 13 or 14 in which said toning includes the steps of forming planar reach in said third location, stopping said film portion in said planar reach, and applying toner to the top of a second belt rotation with a bottom reach substantially parallel to and spaced from said planar reach to dispense said toner onto said film portion, and electrically biasing the first and second belt, one relative to the their along the second reach during the toning step.
19. A method of reproducing as defined in claim 12, 13 or 14 and the step of fixing the transferred image onto said carrier material at a location downstream of the transfer station.
20. An attachment adapted to be operatively coupled with an optical projecting system that includes structure for projecting a light image to an image plane and exposing such a plane to such image for reproducing purposes, said attachment comprising:
A. a rotatable endless belt including at least a portion of an electrophotographic film, the belt having a first planar reach disposed generally at a first plane and a second planar reach disposed at a second plane and proximate to said first plane juxtaposed over said first planar reach but spaced therefrom, means for controlled unidirectional rotation of the belt and positioning said film portion thereof to occupy the reaches sequentially at selected operating stations including a charging station, an exposure station located immediately downstream of said charging station to receive the light image, a toning station and a transfer station in that order;
B charging means located near the commencement of said planar reach for charging the film, said portion of said electrophotographic film being disposed parallel to said second reach while at the exposure station;
C toner supply and dispensing means at the toning station downstream of said exposure station for applying toner to the exposed film portion;
D transfer means at said transfer station downstream of said toning station and along said second reach for bringing a carrier material into close proximity with said toned film portion to transfer a toned image therefrom to said carrier material;
E means for leading the carrier material out of the attachment.
in which the toner dispensing means include a second belt having a top reach and a bottom reach, the toner supply being arranged to apply toner to the top reach of the second belt, the bottom reach of the second belt being juxtaposed parallel to the second reach of the film belt and movable in a direction opposite to the direction of movement of the endless belt, the toner adapted to be carried from the top reach of the second belt around to the bottom reach thereof and thereafter dropped onto the upwardly facing film portion along the second reach so as to tone the latent image carried thereon.
A. a rotatable endless belt including at least a portion of an electrophotographic film, the belt having a first planar reach disposed generally at a first plane and a second planar reach disposed at a second plane and proximate to said first plane juxtaposed over said first planar reach but spaced therefrom, means for controlled unidirectional rotation of the belt and positioning said film portion thereof to occupy the reaches sequentially at selected operating stations including a charging station, an exposure station located immediately downstream of said charging station to receive the light image, a toning station and a transfer station in that order;
B charging means located near the commencement of said planar reach for charging the film, said portion of said electrophotographic film being disposed parallel to said second reach while at the exposure station;
C toner supply and dispensing means at the toning station downstream of said exposure station for applying toner to the exposed film portion;
D transfer means at said transfer station downstream of said toning station and along said second reach for bringing a carrier material into close proximity with said toned film portion to transfer a toned image therefrom to said carrier material;
E means for leading the carrier material out of the attachment.
in which the toner dispensing means include a second belt having a top reach and a bottom reach, the toner supply being arranged to apply toner to the top reach of the second belt, the bottom reach of the second belt being juxtaposed parallel to the second reach of the film belt and movable in a direction opposite to the direction of movement of the endless belt, the toner adapted to be carried from the top reach of the second belt around to the bottom reach thereof and thereafter dropped onto the upwardly facing film portion along the second reach so as to tone the latent image carried thereon.
21. The attachment as defined in claim 20 in which the toner is in a liquid form.
22. The attachment as defined in claim 20 in which means are provided electrically to bias the belts relative to one another across the space between belts to assist in the toning operation.
23. The attachment as defined in claim 20 in which means are provided electrically to bias the belts relative to one another across the space between belts to assist in the toning operation, said bias means including structure for applying a low voltage bias at the beginning of a toning period and a higher bias at the end of such period.
24. The attachment as defined in claim 20 in which the transfer means include transfer roll means engaged against the film surface and providing a nip between itself and the film surface, a supply of said carrier material, and means for leading said carrier material into the nip as said film portion is rotated by the roll means.
25. The attachment as defined in claim 20 in which means are provided for fixing a transferred image on said carrier material before it is led out of the attachment.
26. The attachment as defined in claim 20 in which means are provided electrically to bias said carrier material relative to said film portion.
27. The attachment as defined in claim 20 wherein said immobilizing means comprising a platen located parallel to said reaches and vacuum means associated with said platen to draw said film portion flat against said bottom planar portion in the exact image plane and being releasable to permit linear translation of said film portion toward the toning station.
CLAIMS SUPPORTED BY SUPPLEMENTARY DISCLOSURE
CLAIMS SUPPORTED BY SUPPLEMENTARY DISCLOSURE
28. An attachment adapted to be operatively coupled with an optical projecting system that includes structure for projecting a light image to an image plane and exposing such a plane to such image for reproducing purposes, said attachment comprising:
A. a rotatable endless belt including at least a portion of an electrophotographic film, the belt having a first planar reach disposed generally at a first plane and a second planar reach disposed at a second plane and proximate to said first plane juxtaposed over said first planar reach but spaced therefrom, means for controlled unidirectional rotation of the belt and positioning said film portion thereof to occupy the reaches sequentially at selected operating stations including a charging station, an exposure station located immediately downstream of said charging station to receive the light image, a toning station and a transfer station in that order;
B charging means located near the commencement of said planar reach for charging the film, said portion of said electrophotographic film being disposed parallel to said second reach while at the exposure station;
C toner supply and dispensing means at the toning station downstream of said exposure station for applying toner to the exposed film portion;
D transfer means at said transfer station downstream of said toning station and along said second reach for bringing a carrier material into close proximity with said toned film portion to transfer a toned image therefrom to said carrier material;
E means for leading the carrier material out of the attachment;
A. a rotatable endless belt including at least a portion of an electrophotographic film, the belt having a first planar reach disposed generally at a first plane and a second planar reach disposed at a second plane and proximate to said first plane juxtaposed over said first planar reach but spaced therefrom, means for controlled unidirectional rotation of the belt and positioning said film portion thereof to occupy the reaches sequentially at selected operating stations including a charging station, an exposure station located immediately downstream of said charging station to receive the light image, a toning station and a transfer station in that order;
B charging means located near the commencement of said planar reach for charging the film, said portion of said electrophotographic film being disposed parallel to said second reach while at the exposure station;
C toner supply and dispensing means at the toning station downstream of said exposure station for applying toner to the exposed film portion;
D transfer means at said transfer station downstream of said toning station and along said second reach for bringing a carrier material into close proximity with said toned film portion to transfer a toned image therefrom to said carrier material;
E means for leading the carrier material out of the attachment;
29. The attachment as defined in claim 28 in which the toner is in a liquid form.
30. The attachment as defined in claim 28 in which the transfer means include transfer roll means engaged against the film surface and providing a nip between itself and the film surface, a supply of said carrier material, and means for leading said carrier material into the nip as said film portion is rotated by the roll means.
31. The attachment as defined in claim 28 in which means are provided for fixing a transferred image on said carrier material before it is led out of the attachment.
32. The attachment as defined in claim 28 in which means are provided electrically to bias said carrier material relative to said film portion.
33. A method for reproducing an image onto a sheet carrier material using an electrophotographic film portion of an endless belt including:
rotating said belt unidirectionally through a series of locations spaced along a pair of closely spaced parallel reaches moving said film portion after charging to a second location along the lower one of said reaches downstream of the first location for exposing said charged film portion to the image at the second location, pexposing said charged film portion to the image at the second location, toning said film portion with a liquid toner as it passed through a third location downstream of said second location; and transferring an image from said film portion to a carrier material as it passes through a fourth location disposed downstream of the third location.
rotating said belt unidirectionally through a series of locations spaced along a pair of closely spaced parallel reaches moving said film portion after charging to a second location along the lower one of said reaches downstream of the first location for exposing said charged film portion to the image at the second location, pexposing said charged film portion to the image at the second location, toning said film portion with a liquid toner as it passed through a third location downstream of said second location; and transferring an image from said film portion to a carrier material as it passes through a fourth location disposed downstream of the third location.
34. The method as defined in claim 33 and the additional steps of stopping said film portion at said second location, immobilizing said film portion in an exposure plane at said second location and releasing said film portion upon completion of exposure.
35. The method of reproducing as defined in claim 33 or 34, wherein said toning includes the step of applying an electrical bias during toning.
36. The method of reproducing as defined in claim 33 or 34, wherein said transferring includes: electrically biasing said carrier material relative to the toned film portion during transfer.
37. The method of reproducing as defined in claim 33 or 34, in which said toning includes the steps of forming a planar reach in said third location, stopping said film portion in said planar reach, and applying toner to the top of a second belt rotation with a bottom reach substantially parallel to and spaced from said planar reach to dispense said toner onto said film portion.
38. The method of reproducing as defined in claim 33 or 34, in which said toning includes the steps of forming planar reach in said third location, stopping said film portion in said planar reach, and applying toner to the top of a second belt rotation with a bottom reach substantially parallel to and spaced from said planar reach to dispense said toner onto said film portion, and electrically biasing the first and second belt, one relative to the their along the second reach during the toning step.
39. A method of reproducing as defined in claim 33 or 34 and the step of applying a negative pressure to one side of said film portion at the exposure station to draw said film portion into the image plane and hold same thereat during exposure.
40. A method of reproducing as defined in claim 33 or 34, and the step of fixing the transferred image onto said carrier material at a location downstream of the transfer station.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US80257277A | 1977-06-01 | 1977-06-01 | |
| US802,572 | 1977-06-01 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1133572A true CA1133572A (en) | 1982-10-12 |
Family
ID=25184082
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA304,496A Expired CA1133572A (en) | 1977-06-01 | 1978-05-31 | Plate making attachment for graphic art cameras |
Country Status (9)
| Country | Link |
|---|---|
| JP (1) | JPS5439132A (en) |
| BE (1) | BE867658A (en) |
| CA (1) | CA1133572A (en) |
| CH (1) | CH622627A5 (en) |
| DE (1) | DE2823896A1 (en) |
| FR (1) | FR2393350A1 (en) |
| GB (1) | GB1574570A (en) |
| IT (1) | IT1104701B (en) |
| NL (1) | NL7805921A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| MX146428A (en) * | 1979-02-12 | 1982-06-25 | Coulter Systems Corp | ELECTROPHOTOGRAPHIC COPIER MACHINE WITH REDUCED PROFILE |
| JPH02232654A (en) * | 1989-03-06 | 1990-09-14 | Fuji Photo Film Co Ltd | Processing method for silver halide color photographic sensitive material |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3284224A (en) * | 1963-01-04 | 1966-11-08 | Xerox Corp | Controlled xerographic development |
| DE2008194C3 (en) * | 1969-02-24 | 1974-01-24 | Konishiroku Photo Industry Co., Ltd., Tokio | Electrophotographic copier |
| US3836245A (en) * | 1972-11-29 | 1974-09-17 | Savin Business Machines Corp | Copy machine having photoconductive belt |
-
1978
- 1978-05-31 NL NL7805921A patent/NL7805921A/en not_active Application Discontinuation
- 1978-05-31 IT IT49621/78A patent/IT1104701B/en active
- 1978-05-31 CA CA304,496A patent/CA1133572A/en not_active Expired
- 1978-05-31 GB GB25476/78A patent/GB1574570A/en not_active Expired
- 1978-05-31 CH CH593878A patent/CH622627A5/en not_active IP Right Cessation
- 1978-05-31 FR FR7816264A patent/FR2393350A1/en not_active Withdrawn
- 1978-05-31 JP JP6444378A patent/JPS5439132A/en active Pending
- 1978-05-31 DE DE19782823896 patent/DE2823896A1/en not_active Ceased
- 1978-05-31 BE BE188193A patent/BE867658A/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5439132A (en) | 1979-03-26 |
| IT1104701B (en) | 1985-10-28 |
| BE867658A (en) | 1978-11-30 |
| FR2393350A1 (en) | 1978-12-29 |
| NL7805921A (en) | 1978-12-05 |
| CH622627A5 (en) | 1981-04-15 |
| IT7849621A0 (en) | 1978-05-31 |
| DE2823896A1 (en) | 1978-12-14 |
| GB1574570A (en) | 1980-09-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |