| abstract |
The present invention provides a method for obtaining a molded article having a foamed layer in the molded article, a foaming agent, an apparatus, a mold, a molding machine for the production of a foamable resin, a method for increasing the expansion ratio, and an improved coating Appropriate method. When the carrier resin used for the production of the master batch of the blowing agent is produced from a resin that exhibits compatibility (solubility) with the substance to be blended, a molded article with a good appearance is obtained. When inorganic sodium bicarbonate is used as the foaming agent, the sodium carbonate of the foaming residue (residue after the foaming agent decomposes to generate a foamable gas and remains in the molded product.) reduces the adhesion of the coating film. Therefore, if acid washing is performed in advance to remove sodium carbonate, the coating suitability is satisfied. When GCP is performed, the thickness of the skin layer on the surface varies depending on the temperature of the mold surface. In general, a method of heating water vapor is generally used as a method of increasing the temperature of the mold, but in the present invention, a method of heating a magnetic fluid (liquid) by high-frequency induction provides an inexpensive, high-heating-efficiency, and safe method. The mold heats up. When the method of obtaining a molded product with a high expansion ratio is performed, the mold is withdrawn and the core is withdrawn, and it will be detached from the fixed side. A solution to this problem of detachment by using gas is provided. |