Patent ID: 7914127

Claim:
An ink jet print head structure for printing devices, comprising: a substrate in which one or more slots are located; a nozzle plate connected to said substrate, said nozzle plate defining a first axis (X) and a second perpendicular axis (Y) and comprising a plurality of columns of nozzles extending along the second axis (Y) from which ink is ejected in fluid communication with said one or more slots, said one or more slots extending along said second axis (Y); wherein a plurality of strip-like stress relief elements are located on said nozzle plate, said plurality of stress relief elements being disposed so to extend along the second axis (Y) at least between a pair of columns of nozzles or between a column of nozzles and a boundary of the substrate, each stress relief element of the plurality of stress relief elements defining an aperture on a free surface of said nozzle plate and having a width smaller than the length of said stress relief element, and wherein each of the stress relief elements defines a projection along the first axis (X), and the total projections defined by said plurality of stress relief elements along said first axis (X) have a value between 10% and 55% of the overall width of the nozzle plate along the same first axis (X).