PURPOSE: To obtain an adherent material to be bonded especially suitable for bonding of very small spots by setting a bondable resin layer on an electconductive substrate by electrophoresis.

CONSTITUTION: A resin such as acrylic, epoxy, polyester, polyamide, polyurethane, PE or polyacrylic acid resin is diluted with desalted water into 1-50% solution to give an electrophoresis solution. A substrate is placed on an anode based on a counter electrode in the solution in the case of an anionic system and on a cathode in the case of a cationic system and applied voltage and time are controlled by using DC electric source to form a bonding layer having desired film thickness. An excellent bonding layer having 1-30μm thickness is usually formed at 20-200V applied voltage, 0.5-3A/dm2 current density for 10-180 seconds treatment time. After washing with water, the material to be bonded is predried at about 50-60°C for about 5 minutes, another material to be bonded is stuck to a given position of the material and redried at 80-200°C by a furnace for about 10-30 minutes to bond both the materials completely.