FR2613501A1 - IMAGE RECORDING SYSTEM THAT CAN USE A NEGATIVE ORIGINAL AS WELL AS A POSITIVE ORIGINAL TO PERFORM REPRODUCTION - Google Patents

Abstract

IMAGE RECORDING SYSTEM, INCLUDING A FIRST SUPPORT 11 FOR A LATENT ELECTROSTATIC IMAGE DEFINED BY LOCAL DIFFERENCES IN SURFACE POTENTIAL, A SECOND SUPPORT 18 FOR A BIPOLAR MATERIAL 16 ELECTROSTATICALLY CHARGEABLE POSITIVELY AND POT 2 FOR NEGATIVELY CHARGEABLE OF POT AND NEGATIVELY 2 FOR HOLD THE FIRST AND SECOND SUPPORTS SO THAT THE SURFACE OF THE FIRST SUPPORT IS ADJACENT TO A SURFACE OF THE SECOND SUPPORT, AND TO MOVE THE FIRST AND SECOND SUPPORTS RELATIVE TO THE OTHER IN ORDER TO TRANSFER ELECTROSTATICALLY BIPOLARLY TO THE MATERIAL A THE SURFACE OF THE FIRST SUBSTRATE SO THAT THIS MATERIAL DEPOSITS DIFFERENTLY ON AREAS WITH HIGH POTENTIAL AND ZONES WITH LOW POTENTIAL FROM THE FIRST SUBSTRATE. THE DEPOSIT DEVICE INCLUDES DEPOSIT VOLTAGE APPLICATION MEANS SW1, SW2, HV1, HV2, 32 TO APPLY A TENSIONED VOLTAGE TO BIPOLAR MATERIAL 16 SO THAT THE SET TENSION GENERATES A STRONG AND A LOW POTENTIAL DIFFERENCES TO THE POTENTIALS OF THE HIGH POTENTIAL AND LOW POTENTIAL PARTS OF THE FIRST SUPPORT, RESPECTIVELY, OR VICE VERSA.

Description

The present invention relates to a system for

  recording or imaging capable of reproducing a negative image or a positive image on a photosensitive support, by using a negative original or a positive original either.

  We generally know the photo-

  graphics below, to reproduce a positive color print from a negative or positive image on

  an original film or a slide prepared by a pro-

  photographic transfer using silver halide salts. To reproduce a positive print from

  of a positive initial image, we expose a photo paper-

  sensitive positive-to-positive to radiation through a

  film or slide carrying the initial positive image.

  The exposed photosensitive paper is developed according to a

  image configuration, using a development liquid

  and fix the developed image by means of a li-

  what to fix. This process is called "direct print photography". Alternatively, a photographic film

  instant, such as "SUNPACK AUTOZOOM VIEW PRINTER" (four-

  nor by NIPPON POLAROID KABUSHIKI KAISHA), is exposed to

  through a positive transparent film, so that one pre-

counter a positive draw.

  The most common and generally used method for reproducing a positive print from a

  negative original film involves exposing a photo paper-

  sensitive negative-positive through the original film nega-

  tif and develop the photosensitive paper exposed, at

  using a development fluid.

  In the known methods described above, only the negative film or the film can be used.

  positive as original to reproduce a positive print.

  In other words, the known methods cannot use

  be both negative original films and positive original films to reproduce a positive print at

  from any of the negative or positive films.

  In addition, if the photographic process requires the use

  of a developing liquid, the process tends to be com-

  plicated and requires consumables, such as

  development and fixing fluids, in addition to

  photosensitive port. Therefore, the photogra-

  global phique becomes expensive and the cost of reproducing a print is relatively high. These drawbacks are serious, especially when reproducing a print

  positive enlarged compared to the size of the original.

  In addition, known direct print photography leads to an annoying rejection of spent developer and fixing fluids.

  The present invention aims to avoid the inconveniences

  from the above prior art. Its object is therefore to provide an image recording system which allows cheaper reproduction of a negative or positive image, by using a negative original or

  of a positive original indifferently.

  The above object of the invention can be achieved in accordance with the principle of the present invention

  which provides a compressed image recording system

  nant: (a) a first support to carry an electronic image

  latent trostatic formed on a surface of this support by local potential differences on the surface, the surface comprising parts with high potential and parts with low potential; (b) a second support for

  wear a bipolar material which is electrically chargeable

  statically positively and negatively and (c) deposition means, to support the first and

  second supports so that the surface of the first support

  port is adjacent to a surface of the second support, and to move the first and second supports one

  relative to each other, so as to transfer electro-

  statically bipolar matter on the surface of the first

  support. The depositing means comprise means of

  deposition voltage application, to apply a regulated voltage to the bipolar material. The deposition voltage applying means is provided to operate in either of a low potential mode and a high potential mode, so that the regulated voltage generates

  a big difference in potential compared to a poten-

  such parts of high potential of the first support, and

  a small difference in potential compared to a potential

  tiel of the low potential parts of the first support when the means for applying deposition voltage are placed in the low potential mode, and so that

  the voltage set generates a large difference in poten-

  compared to the potential of the parties with low potential

  tiel of the first support, and a small difference in po-

  potential compared to the potential of the parts of high poten-

  tiel of the first support. Consequently, a corresponding image

  laying down the latent electrostatic image is formed on

  the first support, by the bipolar material which is

  placed on parts with high potential and low potential

tiel in different conditions.

  In the image recording system according to the present invention, constructed as described above,

  a latent electrostatic image is formed by the

  high potential parts and low potential parts of the first support, which are established in accordance with a

  negative or positive image of an original subject to be reproduced

  re. Bipolar material, which is transferred electrosta-

  tick from the second support to the surface of the first support which carries an electrostatic image, is electrostatically charged in a positive or negative manner by a regulated voltage applied to this surface by the means of applying deposition voltage, so that the bipolar material is deposited on high potential and low potential parts under different conditions. As a result, an image corresponding to the latent electrostatic image previously formed is formed by the bipolar material deposited differently on the high potential parts and the low potential parts of the pre-

better support.

  The means for applying deposition voltage can operate selectively in either of the low potential mode and the high potential mode, depending on whether the latent electrostatic image is an image.

  positive or negative image compared to the original image

  ginal to reproduce. Since the potential differences compared to the high potential parts and the low potential parts of the first support are changed by the set voltage applied to the bipolar material, according to

  the operating mode of the voltage application means

  deposition, the conditions under which the bipolar material is electrostatically deposited on the high potential and low potential parts of the first support can be switched as necessary to form a desired positive or negative image corresponding to the latent electrostatic image, which can to be a positive image

  or negative compared to the original image.

  If you use the image recording system

  age considered to reproduce a negative or positive print

  tif by means of a transparent film or slide which

  can be a positive transparent film or a transparent film

  negative, the present system can therefore accept

  both positive transparent films and transparent films

  negative parents. In other words, positive draws can

  can be obtained on the same type of recording medium

  highly photosensitive, even if the image information of

  source is changed from a positive image to a negative image

  tive or vice versa. In addition, the present recording system

  image registration does not require development fluids

  loppement and fixing, usually used, and it eliminates the troublesome handling and evacuation

liquids used.

  The bipolar material used in the present recording system can be a powder or "toner" material. In one embodiment of the present invention, the means for applying deposition voltage

  electrostatically charge positively or negatively

  the bipolar material, in order to deposit electrostati-

  only bipolar matter positively charged or ne-

  selectively on parts of high potential

  and the low potential parts of the first support, se-

  lon that the means for applying deposition voltage are selectively placed in the low potential mode or the high potential mode as described above. Thus, a visible image corresponding to the latent image is formed by the bipolar material negatively or positively charged, deposited on the high potential parts or the low potential parts of the first support. On this subject, it is desirable that the bipolar material has

  a magnetic property and that the second support

  a magnet to provide a magnetic attraction force acting on the bipolar magnetic material, to prevent electrostatic attraction of the magnetic material to one of the high and low potential parts of the first support, at which the regulated voltage applied to the bipolar magnetic material gives the small potential difference. More specifically, the magnetic attraction force generated by the magnet is greater than an electrostatic force acting on the

  bipolar magnetic material carried on the second sup-

Harbor.

  In another embodiment of the pre-

  invention, the means for applying deposition voltage electrostatically charge positively or

  negative bipolar material, in order to deposit electro-

  statically the bipolar material positively and negatively charged on the high potential parts and the low potential parts of the first support, so

  that a first electrostatic attraction force acts

  health on the bipolar material attracted towards one of the par-.

  high potential and low potential ties is greater

  to a second electrostatic attraction force acting

  health on the bipolar material attracted towards the other of the high potential and low potential parts, when the means for applying deposition voltage are placed in one of the low potential and high potential modes,

  and so -the first force of attraction electrostati-

  that is less than the second electric attraction force

  trostatic when the means of applying tension

  are placed in the other of the modes. In this case, the system

  image recording device includes an erasing body

  ment, adjacent to the surface of the first support, to

  lift the bipolar material from the surface of the first sup-

  port, and means for applying erase voltage

  to apply an erasing voltage to the erasing body

  cement which is switchable between a positive and a negative level, in order to remove the bipolar material from the high potential or low potential parts of the first

  support to which the regulated voltage applied to the ma-

  the bipolar field gives the small potential difference.

  More specifically, the parts with high potential or the parts with low potential from which the bipolar material is removed by the eraser body are determined according to

  that the means for applying deposition voltage are placed

  cés in high potential mode or low potential mode. In the present device, also, a

  visible image corresponding to the latent electrostatic image

  tick is finally formed by the bipolar matter deposited

  electrostatically placed on high potential parts

  or the low potential parts of the first support.

  According to an arrangement in one or other of the

  two embodiments of the present recording system

  Truly, described above, bipolar material has

  a light screen property and the en-

  image registration further includes: a third

  support; means to hold the third support already

  hundred to the first support which carries a light screen image constituted by the bipolar material deposited on

  its parts with high potential or its parts with low po-

  essential; means for applying transfer voltage

  to apply to the third support a trans-

  fert in order to transfer the screen image to the light of the

  first support to the third support, so that the tension

  transfer sion is switchable between a positive level

  and a negative level; and means of exposure of sup-

  recording port to expose a recording medium

  highly photosensitive, under the influence of the light screen image on the third medium, so that an image corresponding to the light screen image is formed on the photosensitive recording medium. In this arrangement, the recording medium can be of a type comprising microcapsules, each of which contains a chromogenic material and the mechanical strength of which varies with the degree of exposure to radiation. In

  in this case, means of development are provided for

  be the photosensitive recording medium in the presence

  of development material, and thus break down micro-

  capsules according to their mechanical strength, for a chemical reaction with the developing material

  so as to produce the visible image.

  In the above arrangement, the first support can receive a plurality of electrostatic images at different times and / or in different parts of its surface. In this case, the deposit means are provided for

  form the screen image in light corresponding to each

  one of the plurality of electrostatic images, and the mo-

  transfer voltage application yen work to transfer each screen image to light, corresponding

  laying on each electrostatic image, on the third supp-

  Harbor. In addition, the media support exposure means

  are planned to expose the recording medium

  photosensitive to radiation with different wavelengths, under the influence of images

  corresponding light screen on the third support

  Harbor. According to another arrangement of one or the other of the two embodiments of the invention, described above, the recording system comprises

  further means for holding a recording medium

  adjacent to the first support which carries the bipolar material deposited on its high potential parts or its low potential parts, and application means

  transfer voltage to apply to the support of

  register a transfer voltage in order to transfer

  the bipolar material from the first support to the support of

  registration. The transfer voltage is switchable between a positive level and a negative level. In this case, the bipolar material can comprise at least one material

  chromogen corresponding to at least one color, respectively

  tively. The image recording system further comprises means for fixing the chromogenic material (s)

  transferred to the recording medium.

  In the above arrangement, the bipo- material

  the area comprises a plurality of chromogenic materials

  corresponding to a plurality of colors, respectively,

  and the first support carries a plurality of configurations

  tions of electrostatic images at different times and / or in different parts of its surface. In this case, the depositing means can operate to deposit on the

  first support each of the plurality of chromic materials

  mogens according to a corresponding configuration of the plurality of configurations of electrostatic images. The means for holding a recording medium and the means for applying transfer voltage cooperate to transfer the chromogenic materials corresponding to the

  electrostatic image configurations at the recording medium

  registration, so that the configurations formed by the chromogenic materials are mutually superimposed,

  which creates a visible color image.

  In another embodiment of the invention,

  electrostatic charging means are provided for charging

  uniformly manage the surface of the first support, and means for exposing the first support are provided for exposing the surface of the first support under the influence of source image information carried by an original, which generates on the surface of the first support the latent electrostatic image which corresponds to the information

source image.

  In addition to the foregoing, the invention

  tion includes other provisions which stand out

  from the description which follows.

  The invention will be better understood using the

  further description below, which refers to

annexed drawings in which:

  FIG. 1 is a diagram of an embodiment

  sation of an image recording system according to the

  present invention, in the form of a production apparatus

  color image tion; Figure 2 is a perspective diagram of a tape feed device and a second exposure device of the apparatus shown in Figure 1; Figure 3 (a) is a graph showing the

  spectral transmission factors of three primary colors

* 2613501

  light mayors of an interference filter used in the apparatus of FIG. 1; Figure 3 (b) is a graph showing the

  spectral reflection factors of three primary colors

  res (turquoise, lilac and yellow) of an original; FIG. 4 is a partial elevation view,

  in vertical section, of a photosensitive and sensitive sheet

ble at pressure;

  Figure 5 (a) is a view illustrating different

  potential rents in exposed and unexposed areas of the surface of a photosensitive drum, and a situation in which a developing powder is attracted to the drum, so that an image formed by the developing powder is reversed by compared to a negative image on a transparent film;

  FIG. 5 (b) is a view illustrating different

  potential rents in the exposed and unexposed areas of the surface of the drum, and a situation in which the developing powder is attracted to the drum, so that the image formed by the developing powder is not reversed from a positive image on the transparent film or the slide;

  Figure 6 is a block diagram of a system

  electrical control unit of the color image forming apparatus shown in Figure 1; Figure 7 is a diagram, corresponding to

  that of FIG. 1, which illustrates another embodiment.

  sation of a color image forming apparatus

  in accordance with the present invention;

  FIG. 8 is a diagram illustrating a circuit

  control fired to selectively apply a voltage

  sion set to four app development rollers

  similar color imaging of Figure 7; Figures 9 (a) and 9 (b) are views corresponding to those of Figures 5 (a) and 5 (b) in connection with the embodiment of Figure 7; Figure 10 is a diagram corresponding to

  that of FIG. 1, which illustrates another mode of reaction

  reading of the invention; Figures 11 (a) and 11 (b) are views explaining a process in which a positive print is obtained from a negative transparent film; and FIGS. 12 (a) and 12 (b) are views explaining a treatment in which a positive print

  is obtained from a positive transparent film.

  It should be understood, however, that these drawings and the corresponding descriptive parts are given solely by way of illustration of the subject of the invention, of which they do not in any way constitute

a limitation.

  Reference is first made to Figures 1 and 2 which show a color image forming apparatus

  which includes a first exposure device 1 consisting of

  constituting first means of exposure, a xerographic device 2 constituting means of powder deposition

  development system, a belt feed device 3 cons-

  constituting means of advance, a second device for

  position 4 constituting second means of exposure,

  and a paper feed device 5.

  In the first exposure device 1, a

  transparent film or slide 6, corresponding to an image

  ge of desired source or original to reproduce, is placed interchangeably in appropriate position. Transparent film 6, which carries a positive or negative image

  compared to the original image, is irradiated by a ray-

  scanning operation produced by a light source 7

  trailed by a suitable control device. The Ray-

  which has passed through the transparent film 6 strikes a mid

  see plane 10, via a focal lens

  8 and an interference filter 9. The radiation is reflected by the mirror 10 towards the surface of a photosensitive drum 11 of the xerographic device 2, so that the reflected light is focused on

  the surface of the drum 11. The interference filter 9

  takes three filter elements 9R, 9G, 9B which selectively transmit light rays having wavelengths corresponding to the colors red, green and blue, respectively. These 9R, 9G and 9B filter elements for

  red, green and blue have specific transmittances

  factors or transmission factors as indicated on

  Figure 3 (a). The focusing lens 8 has a

  variable magnification port m. According to a magnification ratio m chosen for the focusing lens 8, the speed of scanning of the film of slide 6 by the radiation is adjusted by the control device of

  the light source 7. Thus, we can modify as

  on the dimension of a latent electrostatic image

  to be formed on the photosensitive drum 11.

  Along the periphery of the photosensitive drum

  ble 11 of xerographic unit 2 are arranged a

  charger 13, an electrostatic charger 14 connected to a high voltage source HvO, a first development device 15 constituting the first development means, and a cleaning device 12, in the order corresponding to a direction of rotation of the drum 11

* (indicated by arrow A in Figure 1).

  When the photosensitive drum 11 rotates, a residual electrostatic charge on the drum is

  eliminated by the unloader 13 and the circumferential surface

  tial discharged from the drum 11 is uniformly electrostatically charged at -650V. When we irradiate the surface

  negatively charged, by means of radiation represented

  of the original image information, the potential

  surface area Vi in unexposed areas decreases slightly-

  ment at -600v, while the electrostatic charge in the exposed areas largely disappears, the surface potential Vl in the exposed areas decreasing to -50V. As a result, a surface electrostatic potential difference configuration is defined by the exposed and unexposed parts of the photosensitive drum 11, so that a latent electrostatic image corresponding to the source image information

is formed on the drum 11.

  The first development device 15

  takes a reservoir of developing powder 17, for

  contain a mass of a bipo- developing powder

  black area 16, electrostatically chargeable positively and negatively. The first device

  development 15 further includes a development roller

  pement 18 of non-magnetic material which serves as a support for carrying the developing powder or "toner" 16. The developing roller 18 contains a cylindrical permanent magnet (not shown) and the toner 16 contains a magnetic powder, so that the toner 16 is attracted

  on the developing roller 18 by the magnetic force

  than magnetic powder. When the roller 18 rotates, the powder 16 contained in the reservoir 17 is displaced towards the surface of the photosensitive drum 11. The developing roller 18 is connected, via cut-off switches SW1 and SW2, selectively to one of two energy sources HV1 and HV2. These sources

  HV1, HV2 serve as a means of applying polarity voltage

  setting, to apply high and low bias voltages of 500V and -100V to the developing roller 18. When the appropriate cut-off switch SW1 or SW2 is placed in its closed ON position, the voltage

  strong or weak development bias is ap-

  plied to the developing roller 18, so that the potential between the photosensitive drum 11 and the developing roller 18 is switched between two values. More specifically, a positively charged powder 16a or a negatively charged powder 16b of the mass of bipolar developing powder 16 is attracted or electrostatically transferred to the exposed or unexposed areas of the surface of the photosensitive drum 11, depending on the potential and the polarity. in exposed and unexposed areas. Since developer powder 16 is a light shielding material, a visible image

  22 screen to light, corresponding to the electro image

  latent static, is formed by the powder 16. When the light screen image 22 is transferred to an endless band 19 transparent to light, as described below, a certain amount of the powder 16 may remain on the circumferential surface of the drum 11. The mass of residual powder is removed by a cleaning blade 12a forming part of the cleaning device 12. The mass

  powder removed is stored in a collection box

tion 12b.

  The tape feed device 3 comprises two feed rollers 20,20 which are rotated by

  appropriate means (not shown). Inter-

  medium, in the form of the transparent endless strip 19 of polyethylene terephthalate, is supported by the

  feed rollers 20, so as to extend horizontally-

  ment between them so that the endless belt 19 is rotated in a direction indicated by an arrowB in FIG. 1.

  Below an upper strand of the endless strip 19 are placed image transfer means under

  the shape of a transfer roller 21 which is located above

  under the photosensitive drum 11, so that the transfer roller 21 and the drum 11 cooperate to clamp between them the upper strand of the endless belt 19. The transfer roller 21 is connected, by switches

  SW3 and SW4, selectively at one of two sources

  these of HV3 and HV4 energy. These sources HV3, HV4 serve as

  transfer voltage application means, for application

  quer negative and positive high voltages to the transfer roller 21. The cut-off switches SW3 and SW4 close and open in response to the corresponding actions.

  of the cutoff switches SW1 and SW2, respectively-

  is lying. The transfer roller 21 is used to charge electro-

  statically the transparent endless band 19, with a

  opposite polarity to that of powder 16a, 16b charged for

  whether or not it is deposited electrostati-

  only on the photosensitive drum 11 as a visible image

  screen ble in light 22. The value of the electric charge

  applied to the transfer roller 21 is

  completed to be sufficient to transfer the

  powder 16a, 16b (i.e. the non-trans-

  visible parent or image 22) on the endless belt 19.

  Thus, the light visible screen image 22 is trans-

  from drum 11 to transparent endless band 19.

  The second exposure device 4 is placed

  cé above a downstream part (on the left side in FIG. 1) of the upper strand of the endless belt 19. This second exposure device 4 comprises a lighting lamp 23, a light collector 24 and a interference filter 25 which comprises three filter elements 25R, 25G and 25B having the same spectral transmission factors as the corresponding filter elements 9R,

  9G and 9B of the interference filter 9 of the first device

tif of exposure 1.

  As shown in Figure 2, the paper feed device 5 is placed along the path of the endless belt 19. The device 5 comprises a storage box 37, to contain a stack of cut sheets

  26 photosensitive and pressure sensitive, and two

  supply waters 28.28 to bring the photo sheets

  sensitive 26 from the bootmaker 27 to the endless belt 19. The device 5 for feeding paper further comprises

  a sheet guide 30, for guiding each recording sheet

  photosensitive texture 26, moved by the feed rollers 28, to an exposure position just below the lower surface of the downstream portion of the upper strand of the endless belt 19, which is aligned

  with the second exposure device 4.

  In the present embodiment, the photosensitive and pressure sensitive sheet 26 is of a color imaging type, comprising a paper substrate 26a, a plurality of microcapsules 26b and a

  development material that are deposited on the sub-

  strat 26a, in a well known manner. The microcapsules 26b contain a radiation-curable resin and

  different chromoqene materials corresponding to the pig-

  elements of the primary colors turquoise, lilac and yellow.

  The chromogenic materials can react chemically with the developing material, so as to produce the

  respective colors. The upper surface of the upper strand

  laughter of the endless band 19, on which the image visi

  ble 22 is, is irradiated by a quantity of ray-

  appropriately from the exposure device 4 through the filter elements 25R, 25G and

  B selectively olaceous in the active nosition. By sui-

  te, the photosensitive sheet 26 is exposed in a confiquration of imaqe to ravonnement through the endless band 19, under the influence of the visible image 22. De

  in more detail, the radiation-curable resin

  tion contained in the microcapsules 26b in the exposed areas of the photosensitive sheet 26 is cured, while the radiation-curable resin contained in

  the microcapsules 26b in the unexposed areas correspond to

  laying down screen powder in the light of the image visi-

  ble 22 remains uncured. So when the photo-

  sensitive 26 is exposed through the endless strip 19

  to radiation transmitted through each of the three elements

  filter elements 25R, 25G, 25B, a corresponding latent image

  laying on the non-transparent visible image 32 is formed

  on sheet 26, for each of the three colors.

  A second developing device in the form of two pressure rollers 29, 29 is placed along the endless strip 19, on the side opposite to the paper feed device, as shown in FIG. 2. The pressure rollers 29 can be reconciled and

  distant from each other. The photosensitive sheet 26 ex-

  posed by the second exposure device 4 is guided

  by the aforementioned sheet guide 30, in a pinch of press-

  roll rollers 29.29. Consequently, the microcapsules 26b

  whose resin has remained uncured are broken and the ma-

  the chromogenic material flows out of the broken microcapsules, so that the chromogenic material reacts chemically with the developing material also provided on the sheet 26. In this way, a visible color image is formed on the photosensitive and sensitive sheet.

pressure 26.

  Another cleaning device 31 is provided under the left end of the endless belt 19, near the

  second exposure device 4. Device 31 includes

  takes a cleaning blade 31a and a collection box

  tion 31b. The non-transparent image visible on the tape

  endless transparent 19, which was used as a pho-

  tomasque, is removed from the strip 19 by the blade 21a and

  stored in recovery box 31b.

  We will now describe, with reference to Figure 6, an electrical control system of the device

  color imaging system constructed as described above

above.

  The control system uses a central unit

  processing unit (CPU) 32 which serves as control means

  of the operation of the device. A control panel

  of operator 33 and a detector S1 are connected to the

  CPU 32. The control panel 33 includes switches

  command switches which include a power switch for commissioning and selector switches for choosing a desired number of copies to be reproduced, a desired image density and other operating conditions

  operation. The sensor S1 is provided to detect the pre-

  sence of the transparent film or slide 6 in the first exposure device 1. A random access memory (ROM) 34 and

  a selective access memory (RAM) 35 are also connected

  strung to CPU 32. ROM 34 stores programs for

  control of the operation of the i-formation apparatus

  mage, and RAM 35 temporarily stores data signals from operator control panel 33

  and detector S1. In accordance with ordering programs

  stored in ROM 34, the CPU 32 controls the first exposure device 1, the xerographic device 2, the tape feed device 3, the second exposure device 4 and the paper feed device

  5. The CPU 32 includes judgment means 32a which

  respond to a signal from control panel 33 to determine whether slide 6 is a positive transparent film or a negative transparent film. Depending on the determination by the judgment means 32a, the CPU 32 controls the cutoff switches SW1 to SW4

  for developer roller 18 and transfer roller

fert 21.

  We now describe a reproduction operation

  tion of a color print on this color image forming apparatus according to a negative image or a positive image on the transparent film 6

  which is prepared by a photographic process with ar-

gent known.

  When the transparent film 6 is a transparent film

  negative parent, the imaging operation is ef-

carried out as follows.

  The image on the negative transparent film 6 is

  composed of colors that are complementary to the colors

  their original image to reproduce. More specifically, the image on the negative transparent film 6 comprises three primary colors of light, i.e.

  red, green and blue, which correspond to the colors

  of the three primary pigments of the image po-

  sitive of origin, namely turquoise, lilac and yellow. These complementary colors (turquoise, lilac and yellow) have spectral reflection factors as indicated on the

  Figure 3 (Figure b). In the first exhibition system

  tion 1, the filter element 9R of red color of the interference filter 9 is initially placed in the active position on the optical path. In this situation, the negative transparent film 6 is scanned by radiation from the light source 7 and the radiation is

  propagates through the focusing lens 8 and the element

  filter 9R. More precisely, only the rays

  miners corresponding to the red colored parts of the film

  -20 negative 6 (parts of turquoise color of the original image-

  gine) are transmitted through the filter element 9R. Ain-

  if, a negative latent image corresponding to the parts

  turquoise of the original image is formed electrostatic-

  on the photosensitive drum 11. The drum 11 serves

  therefore of support for carrying the electrostatic image la-

  attempted. While the photosensitive drum 11 rotates

  and that the latent electrostatic image of color tur-

  quoise thus formed moves towards the deviating roller

  loppement 18 (development device), the switch SW1 is kept closed while the switch SW2 is kept open. More specifically, the high voltage source HV1 is connected to the developing roller 18, of

  so that a bias voltage of -500V is applied

  development roller 18.-As a result, there are

  a positive potential difference of + 450V = -50V -

  (-500V), between the exposed areas of the drum surface

  photosensitive bour 11 and the developing roller 18, as shown in Figure 5 (a). Therefore, the negatively charged developing powder 16b of the

  bipolar powder 16 is attracted electrostatically and thus

  if transferred to the exposed areas of the drum 11, so

  that the non-transparent visible positive image 22 corresponds to

  laying in the turquoise parts of the original image is formed by the powder 16b deposited in the exposed areas

  of the drum 11. Thus, the negative image on the filmtranspa-

  negative rent 6 is reversed in positive image 22 cons-

  light screen powder 16b. On the other hand, there is a negative potential difference of -100C = -600V (-500V) between the unexposed areas of the surface

  of the drum 11 and the developing roller 18. Therefore

  quent, the negatively charged powder 16b is not electrostatically attracted to the unexposed parts of the drum 11. Although an electrostatic attraction force acts on the positively charged powder 16a on the developing roller 18, the powder 16a does not is not drawn to the

  drum 11 since a magnetic force between the powder ma-

  of the toner and the permanent magnet contained in the developing roller 18 is greater than the force

  of electrostatic attraction acting on the powder 16a.

  In response to closing and opening actions

  green of switches SW1 and SW2, switches SW3 and SW4 are open and closed, respectively, so that the positive high voltage source HV3 is connected to the transfer roller 21. As a result, an electric field

  is generated by the transfer roller 21, in a di-

  rection from roller 21 to drum 11, through

  the strip 19. Consequently, an electrostatic force

  that acts on the powder 16b so as to attract the powder 16b on the endless belt 19. Since the endless belt 19 is positively charged while the powder 16b on the drum 11 is negatively charged, the powder 16b forming

  the visible non-transparent positive image 22 is transferred

  ree of the drum 11 on the endless belt 19, during the rotation of the drum 11 and the endless belt 19. In the same manner as described above,

  visible non-transparent positive images 22 correspond-

  dant to the turquoise and yellow parts of the original image are formed on the drum 11 and transferred to the endless band 19 rotating in the direction B, by selection of the filter elements 9G and 9B of green color and color

blue interference filter 9.

  When the endless strip 19 rotates in direction B, a portion of the strip 19 carrying the visible non-transparent positive image 22 which corresponds to the turquoise-colored portions of the original image comes opposite the second exposure device 4. During this time, the photosensitive and pressure-sensitive sheet 26 is distributed from the device 5 for supplying

  paper and it is brought to the exposure position.

  In this situation, the red filter element

  R of the interference filter 25 is chosen to be placed

  in the active position and the part of the strip 19 carrying the non-transparent turquoise image 22 is irradiated at

  radiation emitted by the flashlight

  rabies and transmitted through the filter element 25R. As a result, the microcapsules 26b of the photosensitive sheet 26 which correspond to the turquoise color are exposed according to an image configuration corresponding to the image.

  not transparent or screen in the light 22. More preci-

  The microcapsules 26 located in the unexposed parts of the sheet 26 protected by the light screen powder 16b of the photomask configuration 22 remain uncured, while the microcapsules 26b which are located in the exposed parts of the sheet. are hardened due to exposure to radiation. In this way, a positive latent turquoise imaqe is

  formed on the photosensitive sheet 26.

  We form lilac and yellow positive latent imaqes on sheet 26, in the same way that

  been described above about the turquoise image.

  More specifically, the parts of the endless band 19 carrying the visible non-transparent positive images 22 for the lilac color and the yellow color are aligned with the second exposure device 4 and the green and yellow-appropriate filter elements 25G and 25B of the filters are selectively placed in the active position. In this situation, the photosensitive sheet 26 is exposed

  following an image configuration with trans-

  put through the appropriate filter element 25G, 25B and the photomask 22 for lilac or yellow. The microcapsules 26b for lilac and yellow in the exposed parts

  of sheet 26 are cured by irradiation.

  After forming latent images for the layers

  their turquoise, lilac and yellow on the photosensitive sheet

  ble and pressure-sensitive 26, the sheet 26 passes through the nip of the pressure rollers 29 of the second developing device. As a result, the uncured microcapsules 26b for the three colors break and the chromogenic materials flow from the broken microcapsules

  26b, which causes a chemical reaction between these materials

  res and the development material of the photo sheet

  sensitive 26, thereby producing a positive draft in

  corresponding to the original positive image. As-

  crit above, the reproduction of the positive image on the photosensitive sheet 26 is carried out in the manner and in the following order: 1) the negative transparent film 6 corresponding to

  the original image is set up in the first dispo-

exposure sitive 1;

  2) the negative image on the transparent film 6 is con-

  vertically, by the exposure device 1, in one image

  negative electrostatic formed on the photo drum

  sensitive 11 3) the negative electrostatic image is reversed, by

  the first development device 2, in the image po-

  visible non-transparent sitive 22 composed by the developing powder 16b; 4) the visible positive image 22 is transferred to the endless transparent strip 19, like a light screen photomask, and) a latent image is formed on the sheet

  photosensitive 26, by exposure of the sheet to the ray-

  second exposure device 4, through

  the screen photomask 22 in the light or under the influence

  that of the non-transparent image 22. This latent image is developed by the second developing device 29, 29, into a positive image corresponding to the positive image

on the negative transparent film 6.

  When the transparent film 6 is a positive film

  tif, the image forming operation is performed as follows. The positive image on the transparent film or slide 6 is composed of the same colors as the positive image on the original image. More specifically, the image on the positive transparent film 6 is composed of turquoise, lilac and yellow (colors complementary to the three primary colors of light), which appear on the original positive image. When a latent image

  corresponding to the turquoise image of the transparent film po-

  sitive 6 is formed on the photosensitive and sensitive sheet

  ble at pressure 26, the filter element 9R of the interference filter 9 is initially placed

  of the first exposure device 1 in the ac position

  tive on the path of light, as in the case of

  the reproduction of a positive image from the transparent film

  negative parent 6. In this situation, the positive transparent film 6 is scanned with radiation from the

  light source 7 and the radiation passes through the lens

  the focusing 8 and the filter element 9R. More precisely, only the light rays corresponding to the red parts of the positive film 6 (that is to say the lilac and yellow parts of the original image) are transmitted through the filter element 9R. Thus, a positive latent image corresponding to the non-turquoise parts of the original image is formed electrostatically on the

photosensitive drum 11.

  The switch SW2 is kept closed while the switch SW1 is kept open. Specifically, the low voltage source HV2 is connected to the roller

  of development 18, so that a bias voltage

  tion of -100V is applied to the developing roller 18.

  As a result, there is a negative potential difference of -500V = 600V - (-100V) between the unexposed areas of the surface of the photosensitive drum 11 and the roller.

  development 18, as shown in Figure 5 (b).

  Therefore, the positively charged powder 16a of the

  bipolar development powder 16 is attracted electro-

  statically on the unexposed areas of the drum 11, so that the visible non-transparent positive image 22 corresponding to the turquoise parts of the original image is formed by the powder 16a deposited in the areas not

  on the other hand, there is a different

  rence of positive potential of + 50V = -50V - (-100V) between

  the exposed areas of the surface of the drum 11 and the rou-

  developing water 18. Therefore, the powder posi-

  16a is not electrostatically attracted to the exposed parts of the drum 11. Although a force

  of electrostatic attraction acts on the negative powder

  highly charged 16b on the developing roller 18, the powder 16b is not attracted to the drum 11, since a magnetic force between the magnetic powder 16b of the toner

  and the permanent magnet contained in the developer roller

  pement 18 is greater than the electro-

  static acting on the powder 16b.

  In response to closing and opening actions

  of switches SW2 and SW1, switches SW4 and SW3 are closed and open, respectively, so

  that the high negative voltage source HV4 is connected

  transfer roller 21. As a result, an electric field

* stick is produced by the transfer roller 21, in a direction from the roller 21 towards the drum 11 through the endless belt 19. Consequently, an electrostatic force acts on the developing powder 16a, so as to attract the powder development 16a on the endless belt 19, so that the powder 16a defining

  the visible non-transparent positive image 22 is transferred

  drum 11 on the endless belt 19 during rotation

  tion of the drum 11 and of the endless belt 19. Similarly,

  positive non-transparent images visible 22 corres-

  laying in the lilac and yellow parts of the original image are formed on the drum 11 and are transferred to the endless band 19, by selection of the green and blue color filter elements 9G and 9B of the filter

interference 9.

  After formation of positive non-trans-

  relatives 22 corresponding to the turquoise, lilac and yellow parts of the original image on the endless strip 19, we

  exposes the photosensitive sheet 26 according to a configuration

  image ration using the second exposure device

  tion 4, in the same manner as described above with respect to the color imaging operation using the negative transparent film 6. Since the photomasks composed by the light screen configurations of the powder 16a are positive images, microcapsules

  26b in the unexposed parts of the photosensitive sheet

  sible 26 corresponding to the turquoise, lilac and yellow image parts of the positive transparent film 6 remain uncured, so that a latent image is formed on the photosensitive sheet 26. When the photosensitive sheet 26 thus exposed according to an image is then developed

  by the pressure rollers 29, a positive image in color

  corresponding to the positive image on the transparent film

  positive rent 6 appears on the photosensitive sheet 26.

  As described above, positive reproduction in

  is obtained from the positive transparent film 6, in the following manner and in the order:

  1) The positive transparent film or slide 6 cor-

  responding to the original positive image is set up in the first exposure device 1;

  2) The positive image on the transparent film 6 is con-

  vertically, by the exposure device 1, in one image

  positive electrostatic formed on the photosensitive drum

  sible 11; 3) The positive electrostatic image is converted, by the first developing device 2, into the visible positive image 22 defined by the light screen powder 16a; 4) The visible positive image 22 is transferred to the

  endless transparent strip 19, like a photomask of

  notch in the light; and) A latent image is formed on the photosensitive sheet 26, by exposing the sheet to radiation.

  of the second exposure device 4, through the photo-

  screen mask 22 in the light, and this latent image is developed by the second developing device 29,

  into a positive image corresponding to the posi-

  tive on the positive transparent film 6.

  As described above, when the film trans-

  parent 6 is a negative film, the positivenon image trans-

2613.501

  visible parent 22 is formed by the charged powder ne-

  gatively 16b drawn to the exposed parts of the drum

  photosensitive bour 11. When the transparent film 6 is a positive film, the visible positive image 22 is formed by the positively charged powder 16a attracted to the

  unexposed parts of the drum 11. Thus, the image vi-

  sible 22 is obtained from the negative transparent film 6 or from the positive transparent film 6 equally, by simple operation of the switches SW1-SW4 as described above. A positive image corresponding to the original image is formed on the photosensitive sheet 26, as a result of exposing the sheet through the non-transparent positive image 22 made of the screen powder to light 16a, 16b , regardless of whether the transparent film 6 is a negative film or a

positive film.

  Generally, the spectral characteristics of the exposure light sources 7,23, the photosensitive drum 11 and the photosensitive sheet 26 are not flat. In addition, the turquoise and lilac pigments of a negative color film or a slide obtained by a photographic process with silver salts tend to have an incomplete spectral absorbance. Therefore, we usually use what is called a "mask

  orange "for turquoise and li-

  weary, in the production of negative films. For this reason, unexposed parts of a negative film tend to be orange in color. Given this trend,

  an appropriate compensation filter is provided (not

  presented) on the path of light in the first exposure device 1 of this embodiment,

  to eliminate color distortion on a printout

color product.

  In this image recording system

  A positive color print can be obtained from a negative or positive slide or transparent film by simply switching the SW1-SW4 cutoff switches without changing or replacing components

  in the system. In addition, the present recording system

  greatly eliminates developing and fixing fluids and associated devices or components, which are

  required in the salt photography process

  nice. Consequently, the operation and maintenance of the system are facilitated and the operating cost is reduced, without the use of consumable substances with the exception of the photosensitive recording medium 26. Thus, the present system allows economical reproduction of a color print. In addition, the dimension of the image reproduced on the photosensitive sheet 26 can be easily changed as desired, by modifying the magnification ratio m of the focusing lens 8. Reference is made to FIG. 7 which represents a variant of the embodiment present invention, in which the same reference characters are used as in the previous embodiment to identify the corresponding elements. This device uses an exposure device 1 similar to the first device

  exposure 1 of the previous embodiment. Any-

  times, the exposure device 1 of this embodiment

  Lization includes an interference filter 107 which differs

  of the interference filter 9 of FIG. 1. More precise-

  The interference filter 107 has four elements.

  filter elements 107R, 107G, 107B and 107Y. The filter elements 107R, 107G and 107B have the same functions as the filter elements 9R, 9G and 9B of the filter 9. The filter element 107Y added to the present filter 107 allows the transmission of light rays having wavelengths which correspond to all of the three colors red, green, and blue and it is used to form an image

black (black and white image).

  The xerographic device 2 includes the dis-

  positive cleaning 12, the discharger 13 and the electrostatic charger 14, which have the same functions described

  above about the first embodiment. Any-

  times, the xerographic device 2 uses four

  development components 113, 114, 115 and 116 which are placed

  created along the periphery of the photosensitive drum 11,

  in description order (corresponding to the meaning of ro-

  tation A of the drum). As already described, the surface of the

  drum 11 is negatively charged at -650V by the char-

  geur 14. As a result of exposure to radiation through each filter element 107R, 107G, 107B, 107Y, the surface potential in unexposed parts of the

  drum 11 decreases slightly to -600V, while the po-

  in the exposed parts decreases a lot, to -50V.

  Development devices' 113-116 com-

  take respective development rollers 113a,

  114a, 115a and 116a and developing powder reservoirs

  respectively 113b, 114b, 115b and 116b. The tanks

  113b, 114b, 115b, 116b contain four powder powders

  different development, respectively, turquoise powder 117, lilac powder 118, yellow powder 119 and black powder 120, which correspond to the red, green, blue and black filter elements 107R, 107G, 107B and 107Y , respectively. Development powders

  or toners 117, 118, 119 and 120 are bipolar materials

  electrostatically chargeable positively and negatively and comprising chromogenic materials or pigments corresponding to the colors turquoise, lilac, yellow and black. The developing rollers 113a, 114a, a and 166a are connected to a switching circuit

  112 as shown in FIG. 8, so that a tension

  determined polarization is applied to the rollers

  development following a sequence ordered as

crit below.

  The switching circuit 112 is connected to the

  energy sources HV1, HV2, via the commu-

  break switches SW1, SW2. To simplify and facilitate the explanation, each energy source HV1, HV2 and the corresponding switch SW1, SW2 in its closed position are represented in FIG. 8 as an energy source

  126. The switching circuit 112 comprises four resistors

  variable voltage R1, R2, R3 and R4 and four relays RA1, RA2,

  RA3 and RA4. A cursor of each variable resistance R1-

  R4 is connected to one of two fixed terminals of the corresponding relay RA1RA4. This fixed terminal is normally

  separate from a mobile terminal of the corresponding relay.

  The fixed terminal is connected to earth.

  The movable terminals of relays RA1-RA4 are con-

  connected to the four respective development rollers

  113a-116a. Relays RA1-RA4 are controlled by a device

  suitable control device, as shown in 32,34,35

  in Figure 6 of the previous embodiment.

  Normally, the relays RA1-RA4 are placed in

  open position and all developing rollers

  ment 113a, 114a, 115a, 116a are connected to earth via the mobile terminals of the relays. In this situation, 117-120 development powders are not

  not transferred to the surface of the photosensitive drum 11.

  When the development devices 113-117 are activated, one at a time, in accordance with signals from the control device, the output voltage of the

  energy source 126 (HV1 or HV2) is divided by the re-

  corresponding variable resistor R1-R4, so that the set bias voltage is applied to the respective developing roller 113a-116a via

  of the respective RA1-RA4 relay. Thus, the four arrangements

  development tifs 113-116 are activated sequentially-

is lying.

  As described above, each of the developing rollers 113a-116a is connected to the energy sources HV1, HV2, by the switching circuit 112. When the switch SW1 is placed in the closed position, a bias voltage of -500V is applied with a roller

  selected development 113a-116a. When the commu-

  SW2 is in the closed position, a voltage of

  polarization of -100V is applied to the developing roller

  pement selected. These bias voltages are chosen

  sies so as to transfer the positively charged powders-

  117-120 to the exposed parts or

  unexposed from the photosensitive drum 11, depending on whether the

  mage on transparent film 6 is a positive image or a negative image compared to an original image to

reproduce.

  When turquoise, lilac, yellow and black powders 117-120 are transferred electrostatically

  development rollers 113a-116a to the photo drum

  sensitive 11, as described below in detail, corresponding images 22 turquoise, lilac, yellow and black are formed on the drum 11. These images are transferred to a recording medium 125 in the form of a

  cut sheet stored in a stack in a case 103.

  The recording medium 125 extracted from the housing 103 is distributed on an endless strip 123, while being guided by a guide 122. The endless strip 123 has a gripping element on its outer surface, for gripping the head end of the recording medium 125 at its exit from the housing 103. Unlike the endless strip 19 used in the first embodiment, the endless strip 123 does not need to be transparent to

  light and it is used as a means to suppress

  carry the recording medium 125 and move it between the drum 11 and a transfer roller 121, and between two image fixing rollers in the form of

heating rollers 124,124.

  The transfer roller 121, which is similar to the roller 21 used in the apparatus of FIG. 1, is arranged next to the photosensitive drum 11. This transfer roller 121 is also connected to the sources of energy.

  BV3 or HV4 via the switch

  pure corresponding SW3, SW4, so that a set transfer voltage is applied to the transfer roller 121 and the recording medium 125. As a result, the images 22 formed on the drum 11 are transferred

  electrostatically to the recording medium 125 sup-

worn on the endless belt 123.

  In a first printing cycle, the red filtering element 107R is chosen and the turquoise developing powder 117 is electrostatically transferred to the surface of the drum 11 exposed in image configuration, so that the turquoise image 22 is forms on the drum 11. At the same time, the endless band 123 is loaded with the recording medium 125. When the medium 125 advances with the upper strand in movement of the endless band 123 in rotation, the turquoise image 22 defined by the turquoise powder 117 is transferred to the support 125. The transferred turquoise image 22 is fixed to the support 125 when the support 125 passes through the

  pinching of the heating rollers 124.

  The endless tape 123 is stopped after the return of the recording medium 125, carrying the turquoise image 22, to a predetermined initial position. We begin

  then a second printing cycle.

  In the second printing cycle, the green filter element 107G is chosen and the lilac developing powder 118 is electrostatically transferred.

  on the surface of the drum 11 exposed according to a configuration

  image during rotation of the drum 11. The

  dre lilac 118 is transferred electrostatically to 26-f 135 0 1 give the lilac image 22 on the recording medium, so that the lilac image 22 is superimposed on the image

  turquoise 22 previously formed.

  We also carry out a third cycle of im-

  pressure to form the yellow image 22 on the support 125,

  this yellow image 22 corresponding to an electro-

  latent static formed on the rotating drum 11, as

  result of exposure to radiation through the

  filter color blue 107B. The yellow image 22 de-

  finished by the yellow powder 119 is superimposed on the turquoise and lilac images 22 previously formed on the support 125. In a fourth printing cycle, the latent electrostatic image is formed on the rotating drum

  11, as a result of exposure to radiation through

  to the black filter element 107Y. In this cycle, the

  dre noire 120, to adjust the tone of a color print to be reproduced on the support 125, is transferred to the drum 11 and to the support 125, as a black image 22 superimposed on the turquoise, lilac and yellow images 22. It should be noted that the last print cycle for black image 22 can be

  deleted. In this case, the filter element 107Y and the qua-

  third development device 116 are not used

entered or activated.

  When slide 6 is a transparent film

  negative rent, we place the cutoff switches SW1 and

  SW2 in the closed and open positions, respectively.

  Therefore, in the first printing cycle, the high bias voltage of -500V is applied to the first developing roller 113a via relay RA1 of the switching circuit 112 shown in Figure 8. As a result, a difference potential of + 450V = - 50V - (-500V) is established between the surface potential Vi of the exposed parts of the drum 11 and the potential of the developing roller 113a. Therefore, 26i350

  the turquoise 117 development powder charged negati-

  is attracted electrostatically to the exposed parts of the drum surface, as shown on the

  Figure 9 (a). So the negative image on the film trans-

  parent 6 is inverted into the positive turquoise image 22,

  which corresponds to the turquoise image of the original. From-

  On the other hand, a potential difference of -100V = -600V -

  (-500V) exists between the unexposed parts of the drum 11 and the developing roller 113a. Therefore,

  the turquoise 117 development powder charged negati-

  is not drawn to unexposed parts of the

  drum 11. In addition, the turquoise powder 117 charged for

  is not attracted to the drum 11 due to a magnetic force produced by a permanent magnet provided in the developing roller 113a, as described above with respect to the first embodiment of the

figure 1.

  The turquoise image 22 thus formed on the tam-

  bour 11 is transferred electrostatically to the support

  register 125, by the high positive trans-

  fert applied from the power source HV3 to the transfer roller 121, via the closed switch SW3, in the manner already described in connection with the first mode

of achievement.

  In the second, third and fourth printing cycles, the appropriate relays RA2-RA4 are energized

  sequentially to apply the high polarity voltage

  rization of -500V to the corresponding development rollers

  dants 114a, 115a, 116a. As a result, the developing powders

  ment lilac, yellow and black 118-120 are transferred to form the positive images 22, lilac, yellow and black, on the drum 11 and the recording medium 125, in the same manner as described above. So the pictures

  turquoise, lilac, yellow and black 22 are mutually supportive

  perposed on the recording medium 125, so

  that we get a positive color print.

  When the image on slide 6 is a

  positive image compared to the original image to be repro-

  duire, we close the switch SW2 and we open the com-

  mutator SW1, and the relatively low bias voltage of -100V is applied from the power source HV2 to the developing rollers 113a, 114a, 115a, 116a, via the corresponding relays RA1-RA4. Therefore, a negative potential difference of -500V = -600V - (-100V) is established between the exposed parts of the photosensitive drum 11 and the developing rollers

  113a, 114a, 115a, 116a, so that the charged powder can

  117-120 is attracted electrostatically to the unexposed parts of the drum 11, as indicated on

  Figure 9 (b). So the positive image on the slide-

  tive 6 is converted into the positive turquoise, lilac, yellow or black image 22 formed on the drum 11. Since there is a positive potential difference of + 50V = -50V - (-100V) between the exposed parts of the drum 11 and the appropriate developing roller 113a-116a, the positively charged powder 117-120 is not attracted to the

exposed parts of the drum 11.

  In response to closing and opening actions

  of switches SW2 and SW1, switches SW4 and SW3 are closed and open, so that the high voltage

  negative transfer is applied from the power source

  HV4 to the transfer roller 121. As a result, the positively charged powders 117-120 or the images 22 are transferred from the drum 11 to the support 125. Thus, a positive color print is formed on the support 125,

  from the positive image on slide 6.

  Referring now to Figures 10, 11 (a), 11 (b), 12 (a) and 12 (b) which illustrate a third embodiment of the present invention. In order to shorten

  and to simplify the description, we use the same re-

  fathers than in the previous embodiments for

  designate the corresponding components.

  This modified device is intended to reproduce

  a monochrome print, unlike a color print

  reproduced by the preceding embodiments. More specifically, the xerographic device 2 of this embodiment uses a developing device 213 which contains a black developing powder 217. The

  developer device 213 includes a roller

  development 213a which is connected to the power source HV1 (-500V) or HV2 (-100V) by the cut-off switch SW1 or SW2, as described above with regard to the modes of

  realization of FIGS. 1 and 7. In addition, the photo drum

  sensitive 11 is negatively charged uniformly by

  the electrostatic charger 14, as already described.

  On the other hand, the present embodiment differs from the previous mode shown in Figure 7 in that the xerographic device 2 of this device

  monochrome imaging system includes an ef-

  selectively, generally designated by the reference 222 in FIG. 10. This erasing device 222 is placed between the development roller 213a and the development roller

  transfer 121 placed below the drum 11. The device

  tif 222 includes a hollow drum 221 for removing Dou-

  development dre, which can turn in one direction

  B indicated in FIG. 10, and a roller 214 of selector

  image placed inside the hollow drum 221. The

  image selection roller 214 is connected, via

  SW5, SW6, selective cut-off switch

  two energy sources HV5, HV6. Near the hollow drum 221 is placed a reservoir 215 for storing the black powder 218 which is removed from the drum 11 by the hollow drum 221 in cooperation with the roller 214 of

  image selection, as described below. The switches

  HV1-HV6 cut-off sensors are controlled by an appropriate control device, as indicated in 32,34,35 on the

figure 6.

  We will now describe an operation of the present apparatus, in which a monochrome black and white print is reproduced, from a negative transparent film.

  monochrome in the form of slide 6.

  The light and dark parts of the ne-

  gative on the transparent film 6 are reversed by comparison

  wearing the light and dark parts of the original image to be reproduced. The negatively charged surface of the photosensitive drum 11 is exposed in an image configuration to radiation, under the influence of the negative image carried by the transparent film 6, so that

  the exposed parts of the drum surface correspond to

  tooth in the light parts of the negative image of film 6, which themselves correspond to the dark or black parts of the original image. At the same time, we close and open

  switches SW1 and SW2, respectively, for application

  quer the strong negative bias voltage of -500V to the development roller 213a. Consequently, a positive potential difference of + 450V = - 50V - (-500V) is established between a surface potential V1 of the exposed parts of the

  drum 11 and a surface potential of the pick roller

  development 213a, as shown in Figure 11 (a). Therefore, the negatively charged black powder 217 is attracted electrostatically to the exposed parts of the drum 11. At the same time, there is a negative potential difference of -100V = -600V - (-500V) between a

  surface potential Vi of unexposed parts of the drum

  bour 11 and the potential of the development roller 213a.

  As a result, the black charged development powder posi-

  217 is electrostatically attracted to the parts

  unexposed parts of the drum 11. Thus, the powder 217 is deposited in the exposed and unexposed parts of the drum 11, under different conditions. Before the powder 217 deposited on the drum 11 approaches the

  device 222 for selective erasure, we close and or-

  See switches SW5 and SW6, respectively, so that a large negative erase voltage is applied from the power source HV5 to the image selection roller 214. As a result, the positively charged powder 217, deposited in the unexposed parts of the drum 11, is attracted electrostatically to the surface of the hollow drum 221, while the negatively charged powder 217

  remains on the exposed parts of the drum 11, as shown

  as shown in Figure 11 (b). The remaining negatively charged powder 217 is electrostatically transferred to the recording medium 125 by the transfer roller 121, in the presence of the positive transfer voltage applied to the roller 121 from the power source HV3, via the SW3 switch. Since the zones

  of the support 125 on which the powder 217 is deposited

  correspond to the clear or white parts of the new image

  gative on the transparent film 6, the visible black image reproduced on the support 125 is a positive image by

compared to the original image.

* When slide 6 is a transparent film

  positive in which the light and dark parts correspond

  lay in the light and dark parts of the original to

  reproduce, the operation is as follows.

  In this case, we close and open the switches.

  SW2 and SW1, respectively, so that the low bias voltage of -100V is applied to the roller

  213a. As a result, a difference in poten-

  The positive value of + 50V = -50V - (-100V) is established between the surface potential V1 of the exposed parts of the drum 11 and the surface potential of the developing roller 213a, as shown in Figure 12 (a). Therefore, the negatively charged black developing powder 217 is attracted electrostatically to the exposed parts of the drum 11. At the same time, there is a negative potential difference of -500V = 600V - (-100V) between the

  surface potential Vi of unexposed parts of the drum

  bour 11 and the potential of the development roller 213a.

  As a result, the black developing powder 217 charged

  positively is electrostatically attracted to the

  unexposed parts of the drum 11. Thus, the powder 217 is

  deposits in the exposed and unexposed parts of the drum

  bour 11, under different conditions. In the pre-

  feel, close and open the switches SW6 and SW5, respectively, so that a strong positive erase voltage is applied from the power source HV6 to the image selection roller 214. Consequently,

  the negatively charged powder 217 on the exposed parts

  the drum 11 is removed by the hollow powder removing drum 221, and the positively charged powder 217 remains on the exposed parts of the drum 11 as

  shown in Figure 12 (b). The positively charged powder-

  remaining 217 is electrostatically transferred to the recording medium 125 by the transfer roller

  121, in the presence of the negative transfer voltage ap-

  plied to roller 121 from the feed source

  tion HV4, via the switch SW4. Since the areas of the support 125 on which the powder 217 is

  removal correspond to the dark or black parts of the i

  positive mage on slide 6, the visible black image reproduced on the support 125 is a positive image by

compared to the original image.

  In the present modified embodiment, the quantity of developing powder 217 to be deposited on the drum 11 increases with the potential difference (absolute value) between the surfaces of the drum 11 and the

  development roller 213a. In the case of reproduc-

  tion of a positive print from a negative transparent film, a relatively large amount of the developing powder is deposited in the exposed parts of the drum 11 while a relatively small amount of the powder 217 is deposited in the non- exposed drum 11. In the case of reproducing a positive print. from a positive transparent film, a relatively large amount of the developing powder 217 is deposited in the unexposed parts of the drum 11, while that a relatively small amount of the powder

  217 is deposited in the exposed parts of the drum 11.

  Thus, simple actions of changing the position of the cutoff switches SW1 and SW2 for the developing device 213 cause a change in the conditions under which the powder 217 is deposited in the exposed and unexposed parts of the drum 11, so that the quantity relatively small powder217 is removed from unexposed or exposed parts of drum 11, so

  to generate a visible positive image to be transferred to the

registration port 125.

  Although the present invention has been described in its currently preferred embodiments with

  a certain degree of particularity, it is understood that the

  vention is not limited to the details of the embodiments

  sation illustrated but can be implemented with various

  changes, modifications and improvements that can

  wind appear to those skilled in the art, in the light of

  description above. For example, changes or

  The following changes can be made in the

  note: a) although the photosensitive drum 11 used in the embodiments illustrated in FIGS. 1, 7 and 10 is negatively charged before being exposed in an image configuration to radiation, it

  the photosensitive drum can be positively charged

  sible; b) although the positive transparent film 6 used in the illustrated embodiments is prepared by

  a silver salt photographic process, one can use

  ser a transparent film prepared by other methods. By

  example, you can use a film or other type of media

  transparent port on which an image is printed, painted, drawn or otherwise generated; c) although the photosensitive and pressure sensitive sheet used in the illustrated embodiment

  in FIG. 1 comprises both microcapsules (con-

  holding a chromogenic material and a radiation curable resin) and a developing material on a paper substrate, the photosensitive and sensitive sheet

  at pressure may contain only the microcapsules.

  In this case, the development material is provided on

  a separate recording sheet on which a picture

  desired ge is reproduced; d) the image-forming apparatus of FIG. 1 can use a photosensitive and pressure-sensitive support of which all the microcapsules contain the same chromogenic material to generate a black, yellow, lilac, turquoise color, etc. In this case, an image

  monochrome can be reproduced on photosen-

  sible; e) the image forming apparatus of FIG. 1 can use a photosensitive and pressure-sensitive support which comprises a layer of microcapsules formed on at least one of the opposite surfaces of a non-transparent substrate or of screen at the light. This substrate has a multiplicity of small transparent parts. In this case, the endless transparent strip 19 is placed in close contact with the surface of the photosensitive support on which the layer of microcapsules is formed. In operation, the photosensitive support is irradiated by

  radiation generated by the second exposure device

  sition 4 located on the side of the photosensitive support. The layer of microcapsules of the photosensitive support which is opposite the endless band 19 is exposed in an image configuration to the radiation reflected by the non-transparent image or photomask 22; f) in the second and third embodiments of FIGS. 7 and 10, the developing powders 117-120 and 217 contain chromogenic materials or pigments corresponding to the colors turquoise, lilac, yellow and black, which directly produce color images on the. ordinary recording medium 125. However, powders 117-120, 217 may consist of a mass of microcapsules which include a suitable chromogenic material and a radiation curable resin. In this case, a recording medium 125 has a layer of developing material, and pressure rollers are provided to break the uncured microcapsules,

  so that the chromogenic material flowing from the microcaps-

  broken sules react chemically with the developing material

  development on the recording medium; g) although the exposure device 1 used in the illustrated embodiments is designed so

  that radiation emitted by the light source 7 is trans-

  put through slide 6 it's possible to expose

  the photosensitive drum 11 according to a configuration of

  mage to radiation which is reflected by slide 6.

  As is clear from the above, the information

  vention is by no means limited to those of its modes of

  reading and application which have just been described more explicitly; on the contrary, it embraces all the variants which may come to the mind of the technician in the matter without departing from the framework or the scope of

the present invention.

Claims (16)

Claims   1. Image recording system, characterized in that it comprises:   a first support (11), for carrying an electronic image   latent trostatic formed on a surface of this support by local potential differences on said surface   face, this surface presenting parts of strong poten-   tiel and parts of low potential;   a second support (18) for carrying a bi-material   polar (16,117-120,217) which is electrostatically char-   positive and negative; and   deposition means (2) for supporting said pre-   mier and second supports (11,16,117-120,217), so that said surface of the first support is adjacent to a surface of said second support, and to move said first and second supports relative to each other,   in order to electrostatically transfer said bi-material   polar (16,117-120,217) on the surface of said first support   port, said deposition means (2) comprising means for applying deposition voltage (SW1, SW2, HV1, HV2.32)   to apply a regulated voltage to said bipo- material   laire (16,117-120,217), said means for applying tension   deposition sion operating in either of a low potential mode and a high potential mode, so that said regulated voltage generates a large potential difference with respect to a potential of said parts   high potential of said first support, and low diff-   potential reference relative to a potential of said low potential portions of said first support when   said means for applying deposition voltage are placed   cés in said low potential mode, and so that   said regulated voltage generates a large difference in po-   relative to the potential of said parts of weakness   ble potential of said first support, and a small difference   rence of potential with respect to the potential of said par-   high potential ties of said first support, an image corresponding to said latent image being thus formed on said first support by said bipolar material (16,117-120,217) which is deposited on said parts of high potential and low potential under different conditions. 2. Image recording system according to   claim 1, characterized in that said material bi-   polar (16,117-120,217) is a powder material.   3. Image recording system according to claim 1 or 2, characterized in that said means for applying deposition voltage (SW1, SW2, HV1, HV2, 32) electrostatically charge positively or   negatively said bipolar material to deposit electro   trostatically the bipolar material, positively or negatively charged (16,117-120), selectively on said parts of high potential and said parts of low potential, depending on whether said means for applying voltage   deposit are selectively placed in said low-   ble potential or said high potential mode, so that a visible image corresponding to said latent image   is formed on said first support (11).   4. Image recording system according to claim 3, characterized in that said bipolar material (16,117-120) has a magnetic property, and said second support (18) contains a magnet which   generates a magnetic attraction force which is greater than   due to an electrostatic force acting on said bipolar material carried on said second support, in   a sense which causes the attraction of said bipo- material   water towards one of said high potential and low potential parts of said first support (11) relative   at which said regulated voltage applied to said ma-   bipolar field generates said small difference in po-   essential. 5. Image recording system according to claim 1 or 2, characterized in that said means for applying deposition voltage (SW1, SW2, HV1, HV2.32) electrostatically charge positively or so   negative said bipolar material (217) to deposit electro   statically positively charged bipolar matter   and negatively (217) on said high poten- tial parts   tiel and said low potential parts of said first   support (11), a first electrostatic attraction force   tick which acts on the bipolar material attracted to one of said high potential parts and said low potential parts being greater than a second force   of electrostatic attraction which acts on bi-material   polar attracted to the other of said high poten-   tial and low potential, when said means of ap-   deposition voltage deposition are placed in one of said low potential and high potential modes, and said first electrostatic attraction force being   less than said second: .- e electro- attractive force   static when said voltage applying means are placed in the other of said modes, and in that said image recording system further comprises:   an erasure body (214) adjacent to said sur-   face of said first support (11), to remove said material   bipolar face (217) of said surface of the first support   Harbor; and means for applying erasing voltage   (SW5, SW6, HV5, HV6,32) to apply to said erase body-   ment (214) an erasing voltage which is switchable between a positive value and a negative value, in order to remove said bipolar material (217) from said other   part of the parts of high potential and low poten-   tiel of said first support when said means of ap-   deposition voltage are placed in said pre-   mier mode, and of said first part of the high potential and low potential parts when said means for applying deposition voltage are placed   in said other mode, so that a visible image cor-   corresponding to said latent image is formed on said first support.   6. Next image recording system   any one of claims 3 to 5, characterized in   that said bipolar material (16) has a light shielding, or non-transparency property, and that said image recording system further comprises: a third support (19); means (21) for holding said third support   (19) adjacent to said first support (11) which carries an ima-   non-transparent ge (22) constituted by said bi-material   polar (16) deposited on its said high potential parts or its said low potential parts; transfer voltage applying means (SW3, SW4, HV3, HV4,32) for applying to said third support (19) a transfer voltage to transfer said non-transparent image (22) from said first support (11) to said third support (19), said transfer voltage being   switchable between a positive value and a negative value   ve; and recording medium exposure means (4) for exposing a photosensitive recording medium (26) under the influence of said non-transparent image (22) carried by said third medium, so that an image corresponding to said non-transparent image (22) is formed on said photosensitive recording medium (26). 7. Image recording system according to claim 6, characterized in that said support   photosensitive recording medium (26) includes micro-   capsules (26b) each of which contains a chromo material   gene and whose mechanical resistance varies with the quan-   tity of exposure to radiation, said recording system   image recording further comprising: developing means (29) for pressing said photosensitive recording medium (26) in the presence of developing material and thereby breaking   said microcapsules (26b) as a function of their resistance   this mechanical, for a chemical reaction with said ma-   development in order to produce said visual image   corn. 8. An image recording system according to claim 6 or 7, characterized in that said first support (11) carries a plurality of electrostatic images at different times and / or in different parts of its   surface and said deposition means (2) act to form   sea said non-transparent image (22) corresponding to each of said plurality of electrostatic images, said transfer voltage application means (SW3,   SW4, HV3, HV4,32) operating to transfer heat   that non-transparent image (22) corresponding to each electrostatic image to said third medium (19), and said recording medium exposure means (4) exposing said photosensitive recording medium (26) to radiation having lengths different wave,   under the influence of corresponding non-transparent images   your (22) carried by said third support.   9. Image recording system according to one   any of claims 3 to 5, characterized in that it further includes:   means (121) for holding a recording medium   ment (125) adjacent to said first support (11) which carries   said bipolar material (117-120,217) deposited on sesdi-   your high potential games or its so called low games   ble potential; and transfer voltage application means (SW3,   SW4, HV3, HV4,32) to apply to said recording medium   very (125) a transfer voltage in order to transfer   said bipolar material (22) from said first medium (11) to said recording medium (125), said transfer voltage being switchable between a value positive and a negative value.   10. Image recording system according to claim 9 or 10, characterized in that said   bipolar material (117-120,217) comprises at least one   a chromogenic third corresponding to at least one color, respectively, said image recording system further comprising means (214) for fixing said   at least one chromogenic material on said recording medium registration (125).   11. Image recording system according to claim 9 or 10, characterized in that said at least one chromogenic material of said bipolar material (117-120) comprises a plurality of chromogenic materials corresponding to a plurality of colors respectively,   and said first support (11) carries a plurality of con-   figurations of electrostatic images at different times and / or in different parts of its surface, said depositing means (2) operating to deposit on said   first support (11) each of said plurality of materials   chromogenic res according to a corresponding configuration   of said plurality of configurations of electric images   trostatic, said means (121) for holding a support   recording and said means for applying voltage   transfer sion (SW3, SW4, HV3, HV4,32) cooperating in a way   re to transfer said chromogenic materials, which   respond to said configurations of electrostatic images   ticks, to said recording medium so that the configurations formed by said chromogenic materials   are mutually superimposed, a color image vis- sible being thus engendered.   12. Next image recording system   any one of claims 1 to 11, characterized in   which it further comprises means (14) of electric charge   trostatic for uniformly loading the surface of said first support (11), and means (1) for exposing the first support to expose the surface of said first support (11) under the influence of source image information on an original , so as to form on the   surface of said first support said electrostatic image   that latent which corresponds to the said image information source.   13. Image recording system, character- terrified in that it includes:   a photosensitive support (11) whose electro-   static is variable due to its exposure to a   yonnement; first exposure means (1) for exposing   said photosensitive support (11) so as to form   either one of the first and two   tenth latent electrostatic images due to a diff-   potential reference between said exposed parts and   said unexposed parts, said first electric image   latent trostatic being a positive image with respect to an original image to be reproduced, while the second latent electrostatic image is a negative image with respect to said original image; a non-transparent bipolar material (16) which is electrostatically chargeable positively and negatively; first developing means (15) located opposite said photosensitive support (11), for electrostatically transferring said non-transparent material (16) to said photosensitive support, so as to form a visible image (22) on said photosensitive support;   judgment means (32a) for determining whether the ima-   latent electrostatic ge formed on said photo support   sensitive (11) is said first image or said second image; means for applying deposition voltage (SW1, SW2, HV1, HV2,32) which respond to said judgment means   (32a) so as to apply a bias voltage   glée to said first development means (15), so   to charge electrostatically positively or fa-   negative lesson said non-transparent material (16) for   electrostatically apply the non-transparent material char-   managed positively or negatively selectively on said exposed parts and said unexposed parts, according to a determination result by said judgment means;   an intermediate support (19) disposed so as to   centered on said photosensitive support (11);   transfer means (21) for transferring electro-   statically said visible image (22), constituted by the   non-transparent material deposited (16), of said pho-   sensitive to said intermediate support (19); transfer voltage applying means (SW3, SW4, HV3, HV4) for applying to said transfer means (21) a set transfer voltage, in order to transfer said non-transparent positively or negatively charged material (16) as said image visible (22) audit   intermediate support (19), according to said result of   termination by said judgment means (32a); advance means (3) for bringing said intermediate support (19) carrying said visible image (22) to   a position aligned with a recording medium   tosensitive (26) placed at a distance from said photosensitive support   ble (11); second exposure means (4) for exposing said recording medium (26) to radiation under the influence of said visible image (22) and thereby forming a latent image on said recording medium; and   second development means (29) for   develop said latent image on said recording medium very much in a visible image.   14. An image recording system, characterized in that it comprises: a photosensitive support (11) having a surface on which an electrostatic image is formed due to its exposure to radiation;   exposure means (1) to form selective-   either of a positive latent image and   a negative latent image on said photosen-   sible (11), said first latent image being a positive image with respect to an original image to be reproduced while said second latent image is a negative image with respect to said original image; development means (2) for depositing a   electrostatically charged material (117-120) on the over-   face of said photosensitive support (11), in accordance with the latent image formed on said photosensitive support; transfer means (121, SW3, SW4, HV3, HV4,32) for electrostatically charging an image-bearing support (125) with a polarity opposite to that of said electrostatically charged material (117-120) and thereby transferring   electrostatically said electrostatic charged material-   ment to said image-bearing support; said electrostatically charged material (117-120)   comprising at least three corresponding chromogenic materials   in the colors turquoise, lilac and yellow, these three chromogenic materials being positively and negatively chargeable; said developing means (2) comprising means for applying deposition voltage (SW1, SW2, HV1, HV2, 32) for applying a set bias voltage to said electrically chargeable material (117-120), said bias voltage adjusted being modified according to whether the latent electrostatic image formed on said support   photosensitive is said first or second laten-   you; and said transfer means (121, SW3, SW4, HV3, HV4,32)   comprising switching means (SW3, SW4.32) which   terminate the polarity of said image carrier (125), so that the polarity of the image carrier (125)   is opposite to that of said electrostatic charged material tick (117-120).   15. Image recording system, character-   laughed at in that it includes: latent imaging means (1,11) for   expose a uniformly charged electrostatic surface   ment of a photosensitive support (11) to radiation, under the influence of an image chosen from a positive original image and a negative original image, and   to electrostatically form an electrostatically   that latent corresponding to the original positive or negative image chosen, so that the exposed parts and   unexposed parts of the surface of the photo-   sensitive have different potentials; deposition means (213, SW1, SW2, HV1, HV2.32) for   apply a set voltage to a bipolar char material   electrostatically and positively geable (217) and thereby electrostatically depositing said bipolar material on said exposed and unexposed parts of said photosensitive support (11) so that the polarity of the bipolar material deposited on said   exposed parts is opposite to that of the bipo- material   the area deposited on said unexposed parts; and erasing means (222, SW5, SW6, HV5, HV6) for   selectively removing positively charged bipolar material   vement or negatively (217) of the exposed or unexposed parts   corresponding exhibits of said photosensitive support (11).   16. An image recording system according to claim 15, characterized in that it further comprises transfer means (121, SW3, SW4, HV3, HV4.32) for   transfer said material to a recording medium (125)   positively or negatively charged bipolar third (217)   which remains on said photosensitive support (11).