| 摘要 |
PURPOSE:To obtain a bathtub excellent extremely in heat retaining property by forming the bathtub with a laminated body consisting of three layers or more, to form the external layer and internal layer of the laminated body with layers without ventilating property, and by including filler in one layer of layers placed between the external layer and the internal layer, to set composition in a vacuum state. CONSTITUTION:By a normal method, a projected yellow gel coat layer 5 and a glass fiber reinforced plastics layer 6 (FRP) are molded. After that, on the rear side surface of the FRP layer 6, an internal layer 1 formed with an aluminum sheet is laminated. However, for the surface of the aluminum sheet, the Sheet covered with polyethylene resin is used. In the meantime, to a simplified recessed type, in the same manner, the aluminum sheet is bonded as an external layer 2. After that, the projected type and recessed type are fitted on each other with the gap of 10mm between them. On fitting them on each Other, the peripheral projected type aluminum sheet 2 and recessed type aluminum sheet 1 are bonded to each other with thermal fusion welding. A gap to be generated by fitting On from an injecting port is filled up with polyethylene terephthalate resin as filler 4. After that, the vacuum layer 3 of the vacuum degree of 1mmHg or less is formed. |
