Seal structure of fluid device

A method for sealing a fluid device comprising:

• providing a first member for defining a hollow internal area of a fluid device;
• providing a second member for defining the internal area together with the first member such that the second member is movable relative to the first member;
• providing a seal member for sealing a gap between the first member and the second member, wherein the seal member is fixed to the first member and has a sliding contact member formed of a resin and being in sliding contact with a sliding contact portion of the second member;
• forming a porous film in the sliding contact portion by depositing, by electric discharge between the sliding contact portion and a discharge electrode, an electrode material of the discharge electrode or a substance as a result of a reaction of the electrode material under action of the electric discharge energy on the sliding contact portion;
• and
• forming a resin layer on the porous film by sliding the second member on the sliding contact member in operation of the fluid device, thereby transferring a portion of the resin from the sliding contact member to the porous film to supply the pores of the porous film with the portion of the resin.