Colour electrophotographic method in which the recording sheet is charged to its saturation voltage

Claim 2

AN ELECTROPHOTOGRAPHIC METHOD OF REPRODUCING A COLOUR PICTURE ON A RECORDING PAPER SHEET FROM AN ORIGINAL PICTURE WHILE SUCESSIVELY CHANGING A PLURALITY OF COLOUR FILTERS CORRESPONDING TO THE NUMBER OF REQUIRED COLOURS AND THE SAME NUMBER OF DEVELOPERS INDIVIDUALLY PRODUCING THE COMPLEMENTARY COLOURS OF THE CORRESPONDING COLOUR FILTERS AND REPEATING A NUMBER OF TIMES CORRESPONDING THE NUMBER OF THE FILTERS THE IMAGE-FORMING PROCESS COMPRISING THE STEPS OF IMPARTING AN ELECTRIC CHARGE TO THE ENTIRE SURFACE OF THE RECORDING PAPER SHEET, FORMING A FIRST CHARGE LATENT IMAGE ON THE RECORDING PAPER SHEET CORRESPONDING TO THE COMPLEMENTARY COLOUR OF THE FIRST COLOUR FILTER OF THE ORIGINAL PICTURE THROUGH THE FIRST COLOUR FILTER, DEVELOPING A FIRST COLOUR IMAGE ON THE RECORDING PAPER SHEET ON WHICH THE FIRST LATENT IMAGE HAS BEEN FORMED BY A FIRST DEVELOPER PRODUCING THE COMPLEMENTARY COLOUR OF THE FIRST COLOUR FILTER, AND FIXING THE FIRST COLOUR IMAGE ON THE RECORDING PAPER SHEET, CHARACTERIZED IN THAT IN THE ELECTRIC

Claim 3

A colour electrophotographic method according to claim 1, wherein quantity of the electric charge imparted to the recording paper sheet per unit time in each of second and the subsequent image-forming processes is higher than that in the first image-forming process.

Claim 4

A colour electrophotographic method according to claim 2, wherein quantity of the electric charge imparted to the recording paper sheet per unit time in at least one image-forming process is higher than that in the preceding imaage-forming process.

Claim 5

A colour electrophotographic method according to claim 1, wherein quantity of the electric charge imparted to the recording paper sheet in each of the second and the subsequent image-forming processes is higher than that in the first image-forming process.

Claim 6

A colour electrophotographic method according to claim 4, wherein quantity of the electric charge imparted to the recording paper sheet in at leaSt one image-forming process is higher than that in the preceding image-forming process.

Claim 7

A colour electrophotographic method according to claim 2, wherein charge impartation to the recording paper sheet in each image-forming process is made through electric charge generator means and the control of quantity of the electric charge imparted to the recording paper sheet per unit time is made by controlling the voltage applied to the electric charge generating means.

Claim 8

A colour electrophotographic method according to claim 2, wherein charge impartation to the recording paper sheet in each image-forming process is made through electric charge generating means and the control of quantity of the electric charge imparted to the recording paper sheet per unit time is made by controlling the distance between the electric charge generating means and the recording paper sheet.

Claim 9

A colour electrophotographic method according to claim 2, wherein charge impartation to the recording paper sheet in each image-forming process is made through electric charge generating means and control of the quantity of the electric charge imparted to the recording paper sheet per unit time is made by controlling the grid resistance of the electric charge generating means.

Claim 10

A colour electrophotographic method according to claim 3, wherein charge impartation to the recording paper sheet in each image-forming process is made through electric charge generating means and the control of quantity of the electric charge imparted to the recording paper sheet per unit time is made by controlling the voltage applied to the electric charge generating means.

Claim 11

A colour electrophotographic method according to claim 3, wherein charge impartation to the recording paper sheet in each image-forming process is made through electric charge generating means and the control of quantity of the electric charge imparted to the recording paper sheet per unit time is made by controlling the distance between the electric charge generating means and the recording paper sheet.

Claim 12

A colour electrophotographic method according to claim 3, wherein charge impartation to the recording paper sheet in each image-forming process is made through electric charge generating means and the control of quantity of the electric charge imparted to the recording paper sheet per unit time is made by controlling the grid resistance of the electric charge generating means.

Claim 13

A colour electrophotographic method according to claim 4, wherein charge impartation to the recording paper sheet in each image-forming process is made through electric charge generating means and the control of quantity of the electric charge imparted to the recording paper sheet is made by controlling the time period during which the electric charge is imparted by the electric charge generating means to the recording paper sheet.

Claim 14

A colour electrophotographic method according to claim 5, wherein charge impartation to the recording paper sheet in each image-forming process is made through electric charge generating means and the control of quantity of the electric charge imparted to the recording paper sheet is made by controlling the time period during which the electric charge is imparted by the electric charge generating means to the recording paper sheet.

Claim 15

In an electrophotographic method for reproducing a color picture on a recording sheet from an original picture in which a plurality of color images are formed in superposed relationship on said recording sheet, each color image being formed by an image-forming process comprising imparting an electric charge to the entire surface of said recording sheet, forming a charge latent image on said recording sheet corresponding to the respective color image to be formed on said recording sheet, developing the respective color image on the recording sheet on which the latent image has been formed by a liquid developer containing a developing agent and an electrically insulating liquid, and fixiNg the respective color image on the recording sheet, the recording sheet when subjected to second and subsequent image-forming processes being wet with said electrically insulating liquid, the improvement wherein sufficient electric charge is imparted to said recording sheet during each respective image-forming process so that the charged voltage of the recording sheet in each respective image-forming process is selected at or slightly above its saturation value.

Claim 16

In an electrophotographic method for reproducing a color picture on a recording sheet from an original picture in which a plurality of color images are formed in superposed relationship on said recording sheet, each color image being formed by an image-forming process comprising imparting an electric charge to the entire surface of said recording sheet, forming a charge latent image on said recording sheet corresponding to the respective color image to be formed on said recording sheet, developing the respective color image on the recording sheet on which the latent image has been formed by a liquid developer containing a developing agent and an electrically insulating liquid, and fixiNg the respective color image on the recording sheet, the recording sheet when subjected to second and subsequent image-forming processes being wet with said electrically insulating liquid, the improvement wherein sufficient electric charge is imparted to said recording sheet during each respective image-forming process so that the charged voltage of the recording sheet in each respective image-forming process is selected at or slightly above its saturation value.

Claim 17

A color electrophotographic method according to claim 14, wherein the value of the saturation charged voltage of said recording sheet in the first image-forming process is different from the values of the saturation charged voltages of the recording sheet in second and subsequent image-forming processes.

Claim 18

A color electrophotographic method according to claim 15, wherein the values of the saturated charged voltages of the recording sheet in respective image-forming processes are different from one another.

Claim 19

A color electrophotographic method according to claim 16, wherein charge impartation to the recording sheet in each image-forming process is made through electric charge generator means and control of the quantity of the electric charge imparted to the recording sheet per unit time is made by controlling the voltage applied to the electric charge generating means.

Claim 20

A color electrophotographic method according to claim 16, wherein charge impartation to the recording sheet in each image-forming process is made through electric charge generating means and control of the quantity of the electric charge imparted to the recording sheet per unit time is made by controlling the distance between the electric charge generating means and the recording sheet.

Claim 21

A color electrophotographic method according to claim 16, wherein charge impartation to the recording sheet in each image-forming process is made through electric charge generating means and control of the quantity of the electric charge imparted to the recording sheet per unit time is made by controlling the grid resistance of the electric charge generating means.

Claim 22

A color electrophotographic method according to claim 16, wherein said liquid developer is applied to said recording sheet by means of a roller.

Claim 23

A color electrophotographic method according to claim 15, wherein charge impartation to the recording sheet in each image-forming process is made through electric charge generator means and control of the quantity of the electric charge imparted to the recording sheet per unit time is made by controlling the voltage applied to the electric charge generating means.

Claim 24

A color electrophotographic method according to claim 15, wherein charge impartation to the recording sheet in each image-forming process is made through electric charge generating means and control of the quantity of the electric charge imparted to the recording sheet per unit time is made by controlling the distance between the electric charge generating means and the recording sheet.

Claim 25

A color electrophotographic method according to claim 15, wherein charge impartation to the recording sheet in each image-forming process is made through electric charge generating means and control of the quantity of the electric charge imparted to the recording sheet per unit time is made by controlling the grid resistance of the electric charge generating means.

Claim 26

A color electrophotographic method according to claim 15, wherein said liquid developer is applied to said recording sheet by means of a roller.

Claim 27

A color electrophotographic method according to claim 14, wherein said liquid developer is applied to said recording sheet by means of a roller.