| 摘要 |
1. Heat screen comprising at least a support film (1) in supple plastic material of which one face (1a) is reflective, said face is covered with a first transparent film (2) letting only the infra red rays with a wavelength of at least two microns go through, said first film (2) is integral with the support-film (1), the assembly constituted by the support-film (1) and said first film (2) comprising perforations (4) traversing said assembly through and through, characterized in that it comprises a second film of supple transparent plastic material (5) letting only infra red rays with a wavelength of at least two microns go through, said second film (5) is situated in front of said reflecting face (1a) of the support-film (1), is independent thereof and is perforated, and in that the holes of the assembly (4) constituted by the support film (1) and said first film on the one hand, and those of the second transparent film (5) on the other hand are offset one with respect to the other in order to avoid the phenomena of exchange by convection. |
