| 摘要 |
<p>A water vapour permeable multi-layer thermal insulation 10 includes two water vapour permeable outer layers 16, 18 encapsulating inner air and water vapour permeable layers 14 of insulation material and at least one inner separating layer 12 of an air-open fibrous material. This layer is interleaved with the inner thermal insulation layers 14 and having a mean flow pore size that allows water vapour to move from one side of the at least one inner fibrous separating layer to the other and through the inner insulation layers yet restricts mass movement of air from one side to the other of the at least one inner fibrous separating layer 12 to form a barrier to convection. The multi layer having a moisture vapour transmission rate (MVTR) or at least 1200 g/m2.day and a thermal resistance R of at least 1.40 m2.K/W. The pore size may be in the range 1 to 20 micrometres. The fibres of the fibrous layer may be metallised.</p> |
