Microchannel device and method for producing thereof

A method for producing a microchannel device that has a channel sandwiched between channel walls formed in an inside a porous substrate, comprising:

• placing a channel wall forming material containing a thermoplastic resin and a wax on a surface of the porous substrate by an electrophotographic method to form a channel pattern on the surface of the porous substrate;
• and
• melting the channel wall forming material by heat to allow the channel wall forming material to permeate into the inside of the porous substrate, thereby forming the channel wall in the inside of the porous substrate,
• wherein a SP value of the wax is lower than a SP value of the thermoplastic resin.