| 摘要 |
PURPOSE:To prevent separation of elements each others upon dewing and obtain prominent full heat exchanging efficiency and gas barrier property by a method wherein soluble high polymer molecule is coated on the recessed and protruded surface of porous base material having recessed and protruded surface. CONSTITUTION:The porous base material is provided with recessed and protrusions having predetermined difference between recess and protrusion or more and is worked so that the recessed are buried with the soluble high polymer molecules while the protrusions are formed with the thin film of the same molecules. The difference between recess and protrusion is preferable to be 20-50mum substantially. When the solution of soluble high polymer molecule is coated on the porous base material having adequate recessed and protruded surface, the recesses are buried substantially to form the thick coating of the high polymer molecules while a very thin film of the same is formed on the protrusions. Fibers, forming the porous base material, are projected from the thin film on the protrusions and the connection of mutual fibers enhances the bonding force of the fibers whereby the bonding property thereof against water may be improved. The thick film is formed on the recessed, therefore, the gas barrier property of the whole of the element is not reduced substantially even though the thin film is formed on the protrusions and the full heat exchanging performance may also be kept in prominent condition. |
