Ultrasonic probe, backing material for ultrasonic probe, and method of manufacturing the same

A method of manufacturing a backing material provided on a backside of vibrators for transmitting and/or receiving ultrasonic waves in an ultrasonic probe, said method comprising the steps of:

• preparing a parent material containing one of elastomer and resin and having an insulation property;
• adding an alkoxide of an element of group XIII to group XV except for carbon (C), nitrogen (N), phosphorus (P) and powder of a material having a larger acoustic impedance than that of said parent material into anhydrous alcohol and stirring them to make a mixture liquid;
• adding alcohol and water into said mixture liquid for hydrolysis of the alkoxide in said mixture liquid and heating said mixture liquid for evaporation of the alcohol and water to form an insulation coating containing an oxide of an element of group XIII to group XV except for carbon (C), nitrogen (N), phosphorus (P) on a surface of said powder so as to make composite powder;
• and
• dispersing said composite powder to fill said parent material and curing said parent material with a curing agent.