PVC-coated polyester fabric

PVC-coated polyester fabrics are used as the building materials for the majority of membrane constmctions. In certain cases, fabrics and yam reinforcements made of polyester require special protection against UV radiation. Because of the need for lower water and/or dirt absorption at the edge of polyester fabrics, specially treated Tow wick yarns are used to avoid the unwanted wick effect (see Rg. 3.5, ref. Mehler). 

Typical section of PVC-coated polyester fabric with topcoat. 

This chapter presents one option for approval testing. It is left to the applicant to carry out any further optional testing or to try out other methods, since in this area there are not many standards. Therefore this procedure is written up according to Section B of the Building Products Guidelines. The considerations we have laid out here are ideal for high-quality Type III PVC-coated polyester fabrics. It is certainly possible to transfer this procedure to other types of fabric but then it would be necessary to discuss the individual details again. 

Note that for a PVC-coated polyester fabric 70°C can be reached without any problems. For other fabrics, however, other testing temperatures have to be used, so that under the effect of the sun s rays they do not heat up too much. Until there is evidence of lower testing temperatures, however, 70°C should be set. The evidence of lower testing temperatures can be determined either by calculation using the absorption curves for radiation or by means of tests. 

Transmission, reflection and absorption spectra for a PVC-coated polyester fabric versus wavelength (pm). 

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