According to aspects of the embodiments, there is provided a method of determining the amount of fountain solution employed in a digital offset lithography printing system. Fountain solution thickness is determined from diagnostic images that are printed and analyzed using the existing Image Based Controls (IBC). An analysis of the density of solids, halftones, and background as a function of the fountain solution control parameter is performed to decide on the appropriate level of fountain solution. A latitude window of control parameters is then derived for which the digital offset lithography printing system in operation minimizes the undesirable effects of too much or too little fountain solution.

According to aspects of the embodiments, there is provided a method of determining the amount of fountain solution employed in a digital offset lithography printing system. Fountain solution thickness is determined from diagnostic images that are printed and analyzed using the existing Image Based Controls (IBC). An analysis of the density of solids, halftones, and background as a function of the fountain solution control parameter is performed to decide on the appropriate level of fountain solution. A latitude window of control parameters is then derived for which the digital offset lithography printing system in operation minimizes the undesirable effects of too much or too little fountain solution.

A compliant surface is created with micron scale dimples above an electrically biased conductive layer. The dimpled surface is charged to a desired charge density and filled partially with fountain solution in either order. Then the compliant surface is brought adjacent a charge-retentive surface bearing an electrostatic charged pattern. In examples the fountain solution charge is repelled in the downward directed field under discharged (or uncharged) regions of the charge-retentive surface and is attracted to the surface at the electrostatic charged pattern in the regions of charged pixels. Electrostatic forces drag the fountain solution from the dimples to the charged pixel surface and away from the discharged pixel regions. Electrophoretic forces cause the fountain solution within the dimples to flow up to the charge image and wet the surface. A desired volume is controlled by varying parameters such as nip pressure.

A compliant surface is created with micron scale dimples above an electrically biased conductive layer. The dimpled surface is charged to a desired charge density and filled partially with fountain solution in either order. Then the compliant surface is brought adjacent a charge-retentive surface bearing an electrostatic charged pattern. In examples the fountain solution charge is repelled in the downward directed field under discharged (or uncharged) regions of the charge-retentive surface and is attracted to the surface at the electrostatic charged pattern in the regions of charged pixels. Electrostatic forces drag the fountain solution from the dimples to the charged pixel surface and away from the discharged pixel regions. Electrophoretic forces cause the fountain solution within the dimples to flow up to the charge image and wet the surface. A desired volume is controlled by varying parameters such as nip pressure.

The present disclosure is directed to a multilayer imaging blanket for a variable data lithography printing system, including: a multilayer base having a lower contacting surface configured to wrap around or to be mounted on a cylinder core of the variable data lithography printing system; and a platinum catalyzed fluorosilicone surface layer opposite the lower contacting surface; wherein the multilayer base is a sulfur-free carcass including: a top layer including a sulfur-free rubber substrate such as an ethylene propylene diene monomer (EPDM) rubber substrate, a bottom layer including the lower contacting surface; and a compressible layer disposed between the top layer and the bottom layer, the compressible layer being attached to a surface of the top layer opposite the platinum catalyzed fluorosilicone surface layer and a surface of the bottom layer opposite the lower contacting surface, optionally the top layer further comprises a reinforcing fabric layer, the reinforcing fabric layer attached to a surface of the compressible layer opposite the bottom layer.

The present disclosure is directed to a multilayer imaging blanket for a variable data lithography printing system, including: a multilayer base having a lower contacting surface configured to wrap around or to be mounted on a cylinder core of the variable data lithography printing system; and a platinum catalyzed fluorosilicone surface layer opposite the lower contacting surface; wherein the multilayer base is a sulfur-free carcass including: a top layer including a sulfur-free rubber substrate such as an ethylene propylene diene monomer (EPDM) rubber substrate, a bottom layer including the lower contacting surface; and a compressible layer disposed between the top layer and the bottom layer, the compressible layer being attached to a surface of the top layer opposite the platinum catalyzed fluorosilicone surface layer and a surface of the bottom layer opposite the lower contacting surface, optionally the top layer further comprises a reinforcing fabric layer, the reinforcing fabric layer attached to a surface of the compressible layer opposite the bottom layer.

A formative surface having a conductive base covered with a dielectric and oleophobic/hydrophobic surface layer is created with defined pits to grow micro-puddles of a defined volume. The formative surface is brought into close proximity with a charge retentive surface carrying a charge image. Fountain solution vapor nucleates and grows preferentially on the base of the pits as micro-puddle droplets. The puddles are charged and extracted from the surface to provide a fog of charged droplets of narrow volume and charge distribution. The charged droplets are attracted and repelled respectively from the charged and discharged image regions of the charge retentive surface, thus developing the charged image into a fountain solution latent image. The developed latent image is then brought into contact with a transfer member blanket and split, thus creating on the blanket a fountain solution latent image ready for inking.

A formative surface having a conductive base covered with a dielectric and oleophobic/hydrophobic surface layer is created with defined pits to grow micro-puddles of a defined volume. The formative surface is brought into close proximity with a charge retentive surface carrying a charge image. Fountain solution vapor nucleates and grows preferentially on the base of the pits as micro-puddle droplets. The puddles are charged and extracted from the surface to provide a fog of charged droplets of narrow volume and charge distribution. The charged droplets are attracted and repelled respectively from the charged and discharged image regions of the charge retentive surface, thus developing the charged image into a fountain solution latent image. The developed latent image is then brought into contact with a transfer member blanket and split, thus creating on the blanket a fountain solution latent image ready for inking.

Ink-based digital printing systems useful for ink printing include a secondary roller having a rotatable reimageable surface layer configured to receive fountain solution. The fountain solution layer is patterned on the secondary roller and then partially transferred to an imaging blanket, where the fountain solution image is inked. The resulting ink image may be transferred to a print substrate. To achieve a very high-resolution (e.g., 1200-dpi, over 900-dpi) print with these secondary roller configurations, an equivalent very high-resolution fountain solution image needs to be transferred from the secondary roller onto the imaging blanket. To increase the resolution of the image on the secondary roller, examples include a textured surface layer added to the secondary roller for contact angle pinning the fountain solution on the roll. Approaches to introduce a micro-structure onto the surface layer of the secondary roller, and also superoleophobic surface coatings are described.

Ink-based digital printing systems useful for ink printing include a secondary roller having a rotatable reimageable surface layer configured to receive fountain solution. The fountain solution layer is patterned on the secondary roller and then partially transferred to an imaging blanket, where the fountain solution image is inked. The resulting ink image may be transferred to a print substrate. To achieve a very high-resolution (e.g., 1200-dpi, over 900-dpi) print with these secondary roller configurations, an equivalent very high-resolution fountain solution image needs to be transferred from the secondary roller onto the imaging blanket. To increase the resolution of the image on the secondary roller, examples include a textured surface layer added to the secondary roller for contact angle pinning the fountain solution on the roll. Approaches to introduce a micro-structure onto the surface layer of the secondary roller, and also superoleophobic surface coatings are described.