| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent small pieces of grass wool or the like constituting a heat insulation layer in a flexible duct from being scattered through a communication hole, and ensure aesthetic appearance of a connection part of a main duct and a branch duct.SOLUTION: An annular coating film body 30 is provided in a communication hole 18 with a branch duct 20 in a main duct 10 of a flexible duct 1. The coating film body 30 covers an inner surface 13c of the communication hole 18 in at least a heat insulation layer 13 out of an inner film body 12, the heat insulation layer 13 and an outer film body 14 of the main duct 10.</p> |
