一(yi)般按包裝(zhuang)材料的(de)力學性(xing)能，它可分以下兩(liang)類(lei)(lei)：柔(rou)性(xing)容(rong)(rong)(rong)(rong)(rong)(rong)器(qi)封(feng)(feng)口(kou)裝(zhuang)置。柔(rou)性(xing)容(rong)(rong)(rong)(rong)(rong)(rong)器(qi)是用柔(rou)性(xing)材料，如(ru)紙張、塑(su)料薄膜、復合薄膜等制作的(de)袋(dai)類(lei)(lei)容(rong)(rong)(rong)(rong)(rong)(rong)器(qi)。這(zhe)類(lei)(lei)容(rong)(rong)(rong)(rong)(rong)(rong)器(qi)的(de)封(feng)(feng)口(kou)多與制袋(dai)、充填(tian)構成(cheng)聯(lian)合機(ji)，很(hen)少獨立使(shi)用，由于材料不(bu)同，其(qi)封(feng)(feng)口(kou)裝(zhuang)置也(ye)不(bu)一(yi)樣。剛(gang)性(xing)容(rong)(rong)(rong)(rong)(rong)(rong)器(qi)封(feng)(feng)口(kou)機(ji)。剛(gang)性(xing)容(rong)(rong)(rong)(rong)(rong)(rong)器(qi)是指容(rong)(rong)(rong)(rong)(rong)(rong)器(qi)成(cheng)型后其(qi)形狀不(bu)易改變的(de)容(rong)(rong)(rong)(rong)(rong)(rong)器(qi)，其(qi)封(feng)(feng)口(kou)多用不(bu)同形式的(de)蓋子，常用的(de)有以下幾種。