Patent ID: 8512935

Claim:
A formulation for a hydrophobic photoresist coating to be applied to a surface of a printhead, the formulation comprising: an epoxidized perfluoropolyether having epoxy functional groups; a photoacid generator chosen from metallic onium salts and non-metallic onium salts; a fluorinated organic solvent present in a first amount and being capable of dissolving at least the epoxidized perfluoropolyether; and a fluorinated organic co-solvent present in a second amount and being capable of dissolving at least the photoacid generator, the second amount being less than the first amount; wherein the hydrophobic photoresist coating formulation is to retain its hydrophobicity during and after being formed into the hydrophobic photoresist coating by: applying the formulation onto an area of the printhead surface; exposing at least a portion of the area of the printhead surface to electromagnetic radiation; thermally crosslinking the epoxidized perfluoropolyether on the area of the printhead surface; and developing an unexposed portion of the area of the printhead surface with a fluorinated organic develop solvent.