active ink ejection structure 20 in fig3 there is shown the thermal bend actuator 28 in further detail the thermal bend actuator 28 includes an arm 44 that has a unitary structure the arm 44 is of an electrically conductive material that has a coefficient of thermal expansion which is such that a suitable component of such material is capable of performing work on a mems scale upon expansion and contraction of the component when heated and subsequently cooled the material can be one of many however it is desirable that the material has a young 39 s modulus that is such that when the component bends through differential heating energy stored in the component is released when the component cools to assist return of the component to a starting condition the applicant has found that a suitable material is titanium aluminum nitride tialn however other conductive materials may also be suitable depending on their respective coefficients of thermal expansion and young 39 s modulus the arm 44 has a pair of outer passive portions 46 and a pair of inner active portions 48 the outer passive portions 46 have passive anchors 50 that are each made fast with the ink passivation layer 16 by a retaining structure 52 of successive layers of titanium and silicon dioxide or equivalent material the inner active portions 48 have active anchors 54 that are each made fast with the drive circuitry layer 14 and are electrically connected to the drive circuitry layer 14 this is also achieved with a retaining structure 56 of successive layers of titanium and silicon dioxide or equivalent material the arm 44 has a working end that is defined by a bridge portion 58 that interconnects the portions 46 48 it follows that with the.