Magnetically and electrostatically assisted thermal transfer printing processes

A thermal transfer printing process which comprises incorporating into a thermal transfer printing apparatus with a thermal printhead a transfer element comprising a substrate upon which is contained an ink, contacting the transfer element with a receiver sheet, applying heat imagewise from the printhead to the transfer element, and applying a field between the transfer element and the receiver sheet to enhance imagewise transfer of the ink from the transfer element to the receiver sheet, wherein the ink is contained in a polymeric sponge material situated in a layer on the substrate, and wherein the strength of the field is modulated to meter the amount of ink released from the transfer element.

A thermal transfer printing process which comprises incorporating into a thermal transfer printing apparatus with a thermal printhead a transfer element comprising a substrate upon which is contained an ink, contacting the transfer element with a receiver sheet, applying heat imagewise from the printhead to the transfer element, and applying a field between the transfer element and the receiver sheet to enhance imagewise transfer of the ink from the transfer element to the receiver sheet, wherein the field applied between the transfer element and the receiver sheet is an electric field modulated in imagewise fashion to enable formation of images having image density within a gray scale.

A thermal transfer printing process which comprises incorporating into a thermal transfer printing apparatus with a thermal printhead a transfer element comprising a substrate upon which is contained an ink, contacting the transfer element with a receiver sheet, applying heat imagewise from the printhead to the transfer element, and applying an electric field between the transfer element and the receiver sheet to enhance imagewise transfer of the ink from the transfer element to the receiver sheet, wherein the ink is insulative and the electric field is generated by charging the receiver sheet with a first charging device and charging the transfer element to a polarity opposite to the charge on the receiver sheet with a second charging device, thereby generating an electric field between the transfer element and the receiver sheet which attracts the ink from the transfer element to the receiver sheet.

A thermal transfer printing process which comprises incorporating into a thermal transfer printing apparatus with a thermal printhead a transfer element comprising a substrate upon which is contained an ink, contacting the transfer element with a receiver sheet, applying heat imagewise from the printhead to the transfer element, and applying a field between the transfer element and the receiver sheet to enhance imagewise transfer of the ink from the transfer element to the receiver sheet, wherein the ink is contained in a polymeric sponge material situated in a layer on the substrate.