Film Agricultural

Conventional LDPE films have a radiation window not only in the visible range, but they are also transparent in the mid range of IR region. Heat loss can be controlled by incorporation of Sibelco thermal fillers  into LDPE films.  The use of thermal films in greenhouse application provides the following advantages :
– Protection against the mild frost
– Earlier harvest
– Increase of crop yield and crop quality

Our grades exhibit strong infrared absorptiom properties in the IR-range (between 7 to 14 micros). Thermal fillers reduce heat loss from a greenhouse during nighttime by trapping the infrared heat radiation from the soil and plants that is normally lost. This helps to maintain optimum plant growth conditions by keeping the average temperature higher plus it extends the growing season by allowing crops to be planted earlier in the spring season and to grow longer into the autumn.

Thermicity is a measure of the heat radiation that is lost through the thermal film.

Thermicity is thermal filler concentration dependent and therefore higher concentration will improve the thermicity on the film. When selecting a thermal filler the following criteria need to be carefully considered:

1. Refractive Index of the thermal filler as close as possible to that of the resin ensuring optimal optical (clarity, picture right and haze, picture left) properties of the film,
2. Low oil absorption and reduced surface area to achieve high loadings and avoid interference with processing additives.
3. High purity and low iron oxide content to reduce yellowness while delivering higher stabilities against degradation extending service life.
4. Good compatibility between the thermal additive and the resin in which it will be used 
5. No negative impact on the mechanical properties of the film
6. Hardness of the mineral particle – abrasion during processing

 Sibelco offers a range of fillers based on different minerals to allow the film-processor to make the proper selection for the specific requirements of the film given the above criteria: