PURPOSE: To prevent a step difference from being generated between a sealer and an applied member, by applying the sealer to the connection part of materials thereafter plastisol, containing vinyl chloride polymer or (and) vinyl chloride copolymer and a plasticizer, further applying paint to be overlapped.

CONSTITUTION: Applying plastisol 7 to be overlapped on a normal sealer 2, members 1 and 6 are prevented from exposing their edged parts. A step difference is prevented from appearing between an applying material and the applied member by setting a film thickness to 200W400μm. If the plastisol 7 sets its dynamic viscosity (viscosity in the time of spraying) to 250cps or less, the film thickness, even if it is set to 400μm or less, is uniformly obtained. While in this connection, if the sealer 2 is applied by a spray to the thickness about 400μm or less, a steel plate edge is coated insufficiently with the film thickness being unevenly generated. While the plastisol 7, if its static viscosity (corresponding to the viscosity after application) is set to 9000cps or more, eliminates the so. called overhung.