| 摘要 |
PURPOSE:To provide a hygroscopic packing material having excellent moisture adsorption performance over a long period of time and useful as a container lid, consisting of a (foamed) molding of a uniform mixture of a polyolefin resin and an adsorbent having a specified particle size. CONSTITUTION:95-35wt% polyolefin resin (e.g. PE), 5-70wt% adsorbent having a particle size of 60 mesh or below (e.g silica gel) and optionally, a volatile or heat-decomposable blowing agent (e.g. azodicarbonamide) are kneaded together. The mixture is molded into a sheet. If desired, the sheet is expanded 1.2-2.5- fold by heating. The sheet is punched into the desired shape, thus obtaining a hygroscopic packing material of 0.5-5mm. in thickness. |
