Mandrel for forming a nozzle plate having a non-wetting surface of uniform thickness and an orifice wall of tapered contour, and method of making the mandrel

Abstract

A mandrel for forming an inkjet printer nozzle plate having a non-wetting surface of uniform thickness and an orifice wall of tapered contour, and method of making the mandrel. A metal masking layer is deposited on a glass substrate, the masking layer having an opening therethrough for passage of light only through the opening. Next, a negative photoresist layer is deposited on the masking layer, the negative photoresist layer being capable of photochemically reacting with the light. A light source passes light through the substrate, so that the light also passes only through the opening in the form of a tapered light cone. This tapered light cone will define the tapered contour of a nozzle plate orifice wall to be formed. The negative photoresist layer photochemically reacts with the light only in the light cone to define a light-exposed region of hardened negative photoresist. The negative photoresist layer is thereafter developed to remove negative photoresist surrounding the light-exposed region, so as to define a column of negative photoresist extending into the opening. A layer of non-wetting material is then electroless deposited on the masking layer. A nozzle plate material is now electrodeposited on the non-wetting layer. Next, the column is removed by a solvent and the nozzle plate material having the non-wetting layer adhering thereto is released from the masking layer. In this manner, the nozzle plate having the non-wetting layer of uniform thickness and the orifice wall of tapered contour is made.