Method for preparation of developing solution for developing electrostatic latent images

Claim 1

METHOD OF SUPPLYING A DEVELOPING SOLUTION TO A DEVELOPING CHAMBER IN WHICH A SENSITIZED PAPER HAVING A LATENT IMAGE FLOWING A DEVELOPING SOLUTION COMPRISED OF A LIQUID HAVING A SPECIFIC RESISTANCE GREATER THAN 10**12 OHM CM AND A A SPECIFIC RESISTANCE GREATER THAN 10**12 OHM CM AND A DIELECTRIC CONSTANT LESS THAN THREE, AND ELECTRICALLY CHARGEABLE IMAGE PRODUCING PARTICLES, FROM A LIQUID SUPPLY CONTAINER SPACED FROM THE DEVELOPING CHAMBER TO SAID DEVELOPING CHAMBER THEREBY DEVELOPING SAID LATENT IMAGE; RETURNING THE DEVELOPING SOLUTION FROM THE DEVELOPING CHAMBER TO THE SUPPLY CONTAINER BY TRANSPORTING THE LIQUID THROUGH A CONDUIT, PART OF THE RETURNFLOW SPACED TO PASS ABOVE THE SUPPLY CONTAINER; LOCATING A PARTICLE CONTAINER ABOVE THE SPACED PART OF THE FLOW; FLOWING A QUANTITY OF PARTICLES INTO THE SPACED PART OF THE FLOW TO PROVIDE INCREASED CONCENTRATION OF THE DEVELOPING SOLUTION; ELECTRICALLY CHARGING THE PARTICLES IN THE SPACED PART OF THE FLOW; AND DISCHARGING DEVELOPING SOLUTION INCLUDING THE CHARGED PARTICLES FROM THE SPACED PART OF THE FLOW INTO THE SUPPLY CONTAINER.

Claim 7

A method of supplying a developing solution to a developing chamber in which a sensitized paper having a latent electrostatic image is to be developed, comprising providing a developing solution containing image producing particles in a container separate from said developing chamber and passing said solution from said container to said chamber thereby developing said latent image, said step of providing a developing solution comprising supplying a liquid to said container having a specific resistance greater than 1012 ohm cm and a dielectric constant less than three, returning said developing solution from said chamber to said container by transporting said solution from said chamber by way of conduit means to nozzle means spaced above the top of the level of the liquid in said container, whereby developing solution is discharged from said nozzle means into said container, applying a non-zero electric potential between a point in the liquid in said container and a point in said nozzle means contacting solution therein, and ejecting electrically chargeable image producing particles in the solution in said conduit means, whereby particles passing in said conduit means through said nozzle means are charged by said potential.

Claim 8

A method of supplying a developing solution to a developing chamber in which a sensitized paper having a latent electrostatic image is to be developed, comprising providing a developing solution containing image producing particles in a container separate from said developing chamber and passing said solution from said container to said chamber thereby developing said latent image, said step of providing a developing solution comprising supplying a liquid to said container having a specific resistance greater than 1012 ohm cm and a dielectric constant less than three, returning said developing solution from said chamber to said container by transporting said solution from said chamber by way of conduit means to nozzle means spaced above the top of the level of the liquid in said container, whereby developing solution is discharged from said nozzle means into said container, applying a non-zero electric potential between a point in the liquid in said container and a point in said nozzle means contacting solution therein, and ejecting electrically chargeable image producing particles in the solution in said conduit means, whereby particles passing in said conduit means through said nozzle means are charged by said potential.