Liquid jetting apparatus

A liquid jetting apparatus comprising:

• a flow passage member having a pressure chamber communicated with a nozzle and a liquid supply port communicated with the pressure chamber;
• a piezoelectric element provided on the flow passage member to overlap with the pressure chamber;
• a protective member arranged on the flow passage member to cover the piezoelectric element;
• and
• a supply member formed with a supply flow passage communicated with the liquid supply port of the flow passage member, and adhered to the flow passage member and the protective member to extend over the flow passage member and the protective member,
• wherein a thickness of a layer of a first adhesive adhering the protective member and the supply member is different from a thickness of a layer of a second adhesive adhering the flow passage member and the supply member,
• an adhesion surface between the protective member and the supply member has a surface roughness which is greater than that of an adhesion surface between the flow passage member and the supply member, wherein the adhesion surface between the protective member and the supply member comprises a surface of the protective member and a surface of the supply member and wherein the adhesion surface between the flow passage member and the supply member comprises a surface of the flow passage member and a surface of the supply member.