| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide the base surface coated external parts of a piano capable of maintaining mirror finished surfaces for long tine without the dimensional change by a temp. and humidity. SOLUTION: Thin decorative materials 1, 2, 3, cut out of a sheet (0.6mm thick) of walnut are set by partially and temporally stopping these materials by means of double coated adhesive tapes to the cavity surfaces of mold bodies 11 and a lateral cap 12. After an insert material 4 made of plywood is set, a foamable polyurethane resin is poured into the cavity and, finally, an upper cap 13 is put on to hermetically close the molds. The resin is then foamed and solidified. When the foaming and solidifying are completed, the molding is removed from the molds and the joints of the thin decorative materials 1, 2, 3 are chambered by sand paper, by which the shape finishing is executed. The work is then executed in order of base surface coloring→sealer applying→polishing→polyester clear finish coating→polishing→finish polishing according to an ordinary mirror finish and grazing coating method, thereby the base surface coating mirror finish and grazing coating is completed.</p> |
