Abstract: Systems, apparatuses, and methods of fluid delivery for liquid electrophotography printing. A fluid delivery apparatus includes a charged ink source, a supplemental fluid source, a working suspension tank in fluid communication with the charged ink source and the supplemental fluid source, a sensor, and an optical density control unit. The charged ink source is to store a charged ink mixture including charge directors and toner particles. The supplemental fluid source is to store a supplemental fluid including imaging oil. The working suspension tank is to store a working suspension mixture including the charge directors, the toner particles, and the imaging oil. The sensor is to monitor an optical density of print output of the liquid electrophotography printing apparatus. The optical density control unit is to determine whether to supply an uncharged ink mixture to the working suspension tank in response to the monitored optical density indicating electrical fatigue.

Abstract: In an example, a method includes forming a print agent pattern on an image forming surface and transferring the print agent pattern from the image forming surface to an intermediate transfer member. In a first mode of operation in which a printable substrate is not between the intermediate transfer member and a cleanable medium, the print agent pattern may be transferred from the intermediate transfer member to the cleanable medium and then cleaned from the cleanable medium. In a second mode of operation, the printable substrate may be provided between the intermediate transfer member and the cleanable medium, and the same print agent pattern or a different print agent pattern may be transferred from the intermediate transfer member to the printable substrate.

Abstract: Described herein are methods of cleaning liquid electrophotographic printers and liquid electrophotographic cleaning compositions for use in such methods. The cleaning compositions comprise a resin and a charge director dispersed in a carrier liquid. The cleaning compositions comprise from about 3 wt. % to about 6 wt. % non-volatile solids (NVS). The methods comprise flushing upstream ink feed components of the liquid electrophotographic printer with the cleaning compositions.

Abstract: In an example, a method includes forming a print agent pattern on an image forming surface and transferring the print agent pattern from the image forming surface to an intermediate transfer member. The pattern may then be transferred to a cleanable medium, and then cleaned from the cleanable medium.

Abstract: In an example, a method includes forming a print agent pattern on an image forming surface and transferring the print agent pattern from the image forming surface to an intermediate transfer member. The pattern may then be transferred to a cleanable medium, and then cleaned from the cleanable medium.

Abstract: According to an example, a resin, a charge director, and a pigment may be ground to form a liquid electrophotographic ink.

Abstract: Herein is described a method for the manufacture of a charge director comprising a barium salt. The method comprises reacting barium alkoxide with an acid in a reaction medium comprising ethanol, and separating ethanol from the reaction mixture to recover the barium salt produced.

Abstract: A magenta liquid electrostatic ink composition includes chargeable particles having a resin and a pigment; an insulating, non-polar, non-aqueous liquid carrier in which the chargeable particles are dispersed; and a charge director. The resin is formable from polymerizing alkylene monomers and methacrylic or acrylic acid monomers; the pigment is selected from pigment violet 19 type ?I, pigment violet 19 type ?II, pigment violet 19 type 1, pigment red 177, pigment red 208, and pigment violet 32; and the liquid electrostatic ink composition lacks any other types of pigment.

Abstract: Herein is disclosed a magenta liquid electrostatic ink composition comprising chargeable particles comprising a resin, a pigment, a liquid carrier in which the chargeable particles are dispersed, and a charge director, wherein the resin is formable from polymerizing alkylene monomers and methacrylic or acrylic acid monomers, the pigment is selected from pigment violet 19 type ?I pigment violet 19 type ?II pigment violet 19 type ?, pigment violet 19 type ?, pigment red 177, pigment red 208, pigment red 122 and pigment violet 32, and the liquid electrostatic ink composition lacks any other types of pigment. Also disclosed herein is a method of electrostatic printing and a print substrate having printed thereon the magenta liquid electrostatic ink composition.

Abstract: Herein is described a method for the manufacture of a charge director comprising a barium salt. The method comprises reacting barium alkoxide with an acid in a reaction medium comprising ethanol, and separating ethanol from the reaction mixture to recover the barium salt produced.

Abstract: The present disclosure discloses a liquid electrophotographic ink. The ink includes a liquid vehicle, an ethylene acid copolymer, and an ethylene/(meth)acrylic acid C1-10 alkyl ester copolymer. Also disclosed is a method for the manufacture that ink and a method for performing a liquid electrophotographic process by printing a substrate with the ink.

Abstract: A method of producing an electrostatic ink composition, the method comprising: providing a precursor ink composition comprising a resin and a pigment dispersed in a liquid carrier; wherein the precursor ink composition comprises 30 wt % or more non-volatile solids; and spraying a lubricating liquid onto the surface of the precursor ink composition to form the electrostatic ink composition.

Abstract: Herein is disclosed a magenta liquid electrostatic ink composition comprising chargeable particles comprising a resin, a pigment, a liquid carrier in which the chargeable particles are dispersed, and a charge director, wherein the resin is formable from polymerising alkylene monomers and methacrylic or acrylic acid monomers, the pigment is selected from pigment violet 19 type ?I pigment violet 19 type ?II pigment violet 19 type ?, pigment violet 19 type ?, pigment red 177, pigment red 208, pigment red 122 and pigment violet 32, and the liquid electrostatic ink composition lacks any other types of pigment. Also disclosed herein is a method of electrostatic printing and a print substrate having printed thereon the magenta liquid electrostatic ink composition.

Abstract: According to an example, a liquid electrophotography printing (LEP) apparatus includes a fluid chamber to store fluid to be used to form an image and a filtration assembly to filter the fluid of the fluid chamber. The filtration assembly may store a filtration material to filter the fluid received from the fluid chamber and may provide the filtered fluid to the fluid chamber. The LEP apparatus may also include a detector assembly to detect a fluid parameter of the filtered fluid in the fluid chamber and a filtration adder unit to add a predetermined amount of the filtration material to the filtration assembly in response to a detection of the fluid parameter by the detector assembly.

Abstract: The present application relates to a method for concentrating an ink for an electrostatic printing process, wherein the method comprises the steps of: (a) providing the ink for an electrostatic printing process, the ink comprising chargeable particles in a liquid carrier; (b) passing the ink between a chargeable conveyor and a first electrode, wherein a potential is applied such that the ink becomes adhered to the chargeable conveyor; (c) passing the ink on the conveyor past a moving surface, wherein the ink contacts the moving surface and a potential is applied between the conveyor and the moving surface, such that the chargeable particles are disposed to move toward the conveyor and some of the liquid carrier is removed to increase the concentration of the chargeable particles in the liquid carrier on the conveyor to form a concentrated ink on the conveyor, the conveyor and the moving surface then diverging from one another, such that substantially all of the concentrated ink remains on the conveyor; (d)

Abstract: A method of producing an electrostatic ink composition, the method comprising: providing a precursor ink composition comprising a resin and a pigment dispersed in a liquid carrier; wherein the precursor ink composition comprises 30 wt % or more non-volatile solids; and spraying a lubricating liquid onto the surface of the precursor ink composition to form the electrostatic ink composition.

Abstract: According to an example, a liquid electrophotography printing (LEP) apparatus includes a fluid chamber to store fluid to be used to form an image and a filtration assembly to filter the fluid of the fluid chamber. The filtration assembly may store a filtration material to filter the fluid received from the fluid chamber and may provide the filtered fluid to the fluid chamber. The LEP apparatus may also include a detector assembly to detect a fluid parameter of the filtered fluid in the fluid chamber and a filtration adder unit to add a predetermined amount of the filtration material to the filtration assembly in response to a detection of the fluid parameter by the detector assembly.

Abstract: A method of maintaining a photoconductive member of a liquid electrophotography printing apparatus (LEP) is disclosed. The method includes storing a fluid having at least fluid particles and a carrier liquid in a fluid chamber and removing at least a portion of the fluid particles and the dissolved materials from the fluid through adsorption by filtration material disposed within a filtration assembly to form a filtered fluid. The method also includes maintaining the photoconductive member by periodically applying the filtered fluid to the photoconductive member and removing the filtered fluid and fluid residue therefrom.

Abstract: The present disclosure discloses a liquid electrophotographic ink. The ink includes a liquid vehicle, an ethylene acid copolymer, and an ethylene/(meth)acrylic acid C1-10 alkyl ester copolymer. Also disclosed is a method for the manufacture that ink and a method for performing a liquid electrophotographic process by printing a substrate with the ink.

Abstract: The present disclosure provides for a liquid electrophotographic (LEP) ink comprising a carrier fluid, a pigment, a high melt viscosity ethylene acrylic acid copolymer resin, and a high acid ethylene acrylic acid copolymer resin. The high acid ethylene acrylic acid copolymer resin can have an acid content of at least 15 wt % and a viscosity of at least 8,000 poise. Additionally, the LEP ink can have a total resin acidity of at least 15 wt % and a total resin melt viscosity of at least 20,000 poise.