| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide good air-permeability and appropriate humectancy by forming plural air pores perforated through a sheetlike body so that the scattered release of steam without a condensate can be secured. SOLUTION: The laminated sheet 11 comprises a water retention layer 13 with water absorptive and humectant properties and a packing face layer 15 which are fusion-bonded by heat through a thermoplastic resin thin film 17 to be integrally laminated together. An air trap formation layer 19 is formed between the water retention layer 13 and the thermoplastic resin thin film 17 as well as the thermoplastic resin thin film 17 and the packaging face layer 15 and many air pores 22 are perforated running through a sheet body. The air pore 22 becomes slightly smaller in inside diameter toward the water retention layer 13 from the packaging face layer 15. In addition, the air pore 22 is tapered in section and has 0.1-2 mm inside diameter on the packaging face layer 15 side, and 6,000-80,000 pieces of the pore per 1 m2 are formed at an interval of 3-20 mm. The porosity is preferably 0.1-15% to the area of the laminated sheet. For the water retention layer 13, the use of water absorbing paper is preferred. For the packaging face layer 15, a nonwoven fabric of a long fiber structure using a composite paper formed of a polymer of at least two components, is used.</p> |
