Method for surface mounting using cleaning-free activated resinous composition

A method for surface mounting comprising the steps of:

• coating at least soldered surface of a printed wiring board with an activated resinous composition which contains 100 parts by weight of an epoxy resin being solid at a room temperature, 1 to 10 parts by weight of a carboxylic acid compound, 1 to 30 parts by weight of a curing agent, a curing reaction initiation temperature of said curing agent being in a range of 150 to 200° C., and 10 to 300 parts by weight of a solvent;
• loading a surface mount component on the printed wiring board resulting in a void space between the coated resinous layer and said surface mount component;
• reflow soldering said surface mount component on the printed wiring board by being guided through a reflow apparatus set to a temperature of 240 to 300° C. in 1 to 10 minutes, causing gas bubble, void or moisture to be evacuated in the form of vapor from the coated resinous layer and yielding a coated resinous layer capable of developing tackiness when subsequently cooled and re-heated to a temperature higher than the softening temperature of the coated resinous layer but lower than the curing reaction initiation temperature;
• and
• heat curing the coated resinous layer.