special functional type backsheet—transparent/1500v high voltage
product series
| model | structure | thinckness | color |
| bef-402 | po/f-coating/pet/f-coating | 200μm/5μm/250μm/15μm | white /black |
| bec-301t | f-coating/pet/f-coating | 15μm/250μm/15μm | transparent |
introduction
firstbacksheet® bef-402 is a backsheet with more than 1500vdc partial discharge, which consist of po layer, hydrolysis resistant pet layer and two fluorine coating layers. bef-402 has excellent insulation and moisture barrier property, which can meet the application requirement of high voltage pv modules.
firstbacksheet® bec-301t is transparent designed as tri-layer structure, which not only has high light transmittance and low haze, but also has excellent insulation performance and long term weather durability property. bec-301t can be used in building and double power modules with the advantage in lightweight and lamination condition.
basic property
| property | quoted standard | unit | bef-402 | bef-402b | bec-301t |
| color | / | / | white | black | transparent |
| peeling strength with eva | gb/t 2790-1995 | n/10mm | >100 | >100 | >100 |
| water vapor transmission rate | astm f1249-2006 | g/m2.24h | <1.5 | <1.5 | <1.5 |
| comparative tracking index | iec 60112-2009 | v | >600 | >600 | ≥400 |
| partial discharge （in air） | iec 60664-1 | vdc | >1600 | >1600 | >1000 |
| transmittance(400-700nm) | gb/t 29848-2013 | % | <5.0 | <5.0 | >85 |
| haze(400-700nm) | gb/t 29848-2013 | % | / | / | <25 |
