Method For Printing Viewable Transparent Ink

A method for printing viewable transparent ink comprising:

• disposing a dark ink onto a substrate to form a solid dark ink layer on the substrate in an area where a diagnostic image will be printed;
• disposing a clear ink onto the solid dark ink layer to form a clear ink diagnostic image, wherein clear ink drops hit and displace the dark ink creating clear holes which provide a density contrast;
• curing or drying after forming the clear ink diagnostic image;
• wherein the clear ink diagnostic image is rendered visible by the contrast between the clear ink diagnostic image and the substrate as compared to the dark ink layer and the substrate.

An inkjet printer comprising:

• at least one print head having at least one inkjet from which a first ink is ejected;
• at least one print head having at least one inkjet from which a second ink is ejected;
• wherein the first ink has a first color density and the second ink has a second color density that is different from the first ink color density;
• a user interface through which data is entered for processing within the inkjet printer;
• at least one actuator operatively connected to the at least one print head that ejects the first ink;
• at least one actuator operatively connected to the at least one print head that ejects the second ink;
• at least one radiation source for curing or drying printed ink images;
• and
• a controller operatively connected to the at least one print head that ejects the first ink, the at least one print head that ejects the second ink, the at least one actuator, the at least one radiation source, and the user interface, the controller being configured:
• to operate the at least one print head having at least one inkjet from which the first ink is ejected to print an uncured solid first ink layer onto a substrate;
• to operate the at least one print head having at least one inkjet from which the second ink is ejected to print a diagnostic pattern onto the uncured solid first ink layer, such that the second ink drops hit and displace areas of the uncured solid first ink layer creating density holes which provide a density contrast;
• and
• to operate the at least one radiation source to cure or dry the printed image after the second ink diagnostic pattern is printed, wherein the second ink diagnostic pattern is rendered visible by the contrast between the second ink diagnostic pattern and the substrate as compared to undisplaced first ink layer areas and the substrate.