加拿大蒙特利尔市一家造纸厂生产了一种自行粘合密封纸，利用该纸包装食品，可避免包装时线绳捆绑或装订的麻烦。这种纸外层是牛皮纸，供书写和印刷，内层是特殊聚丙烯发泡材料，具有坚韧、无毒、保湿、保温等性能，所包装食品的汁液和气味不会外泄。此外，这种纸一经拆封即失 A paper mill in Montreal, Canada, produces a self-adhesive sealing paper that can be used to avoid the need to bind or staple strands during packaging. The outer layer of this paper is kraft paper for writing and printing, the inner layer is a special polypropylene foam, with a tough, non-toxic, moisturizing, heat preservation and other properties, the packaged food juice and odor will not leak. In addition, this kind of paper once opened and lost