Diagnostic sheet and detection method for inkjet prints using paper precoat solutions

A method for diagnosing inkjet printing system performance, comprising:

• providing a diagnostic sheet to an inkjet printing system, wherein the diagnostic sheet comprises a top surface comprising a layer of material that changes color after contacting a precoat solution;
• depositing a quantity of a colorless precoat solution on a top surface of the diagnostic sheet, resulting in a colorimetric change of the layer of material by jetting a plurality of drops of precoat solution using a printhead comprising a plurality of individual jets;
• analyzing the colorimetric change to identify a presence or location of precoat solution corresponding to one or more locations where the quantity of colorless precoat solution was deposited;
• and
• disabling one or more jets if the presence or location of precoat solution identified on the diagnostic sheet is different than an expected presence or location.

A diagnostic sheet, comprising:

• a substrate having a first surface and a second surface;
• and
• a layer of material disposed on the first surface of the substrate;
• and
• wherein the layer of material comprises 1-(1-Hydroxy-2-naphthylazo)-6-nitro-2-naphthol-4-sulfonicacidsodium salt, 3-hydroxy-4-[(2-hydroxy-4-sulfonaphthalen-1-yl)diazenyl]naphthalene-2-carboxylic acid, 1-(1-hydroxy-4-methyl-2-phenylazo)-2-naphthol-4-sulfonic acid, or a combination thereof, and the layer of material changes color when in contact with a precoat solution.