| 摘要 |
The present invention relates to a blow-molding method using a foam resin and a device thereof. The present invention is to solve a problem of a high rate of defects such as tearing or bursting due to a low tensile force when blow-molding in the case of using the foam resin capable of maintaining necessary strength while having a light weight due to multiple internal air layers among various kinds of synthetic resins. The blow-molding method using a foam resin successively performs the following steps of: forming the foam resin by uniformly mixing 5-10% of gas with respect to the whole volume with a polypropylene (PP) material or a polyethylene (PE) material; inputting the foam resin into molds and thereafter closing the molds; injecting air into the molds to start the blow-molding; absorbing air between the molds and the foam resin by operation of a vacuum pump to enable the foam resin to stably adhere to the molds; stopping the air injection and cooling the formed foam resin product; stopping operation of the vacuum pump and opening the molds; extracting the product; and post-processing. The blow-molding device forms the product by inputting parison between at least two molds including a first mold and a second mold, closing the molds, injecting air to the molds to expand the parison toward an inner wall of the cavity. The present invention relates to the blow-molding method using the foam resin by including a vacuum duct wherein a vacuum pressure is applied by the vacuum pump and a through hole penetrating from the vacuum duct to the inner wall of the cavity to apply the vacuum pressure between the parison and the inner wall of the cavity. |
