Greenhouse Films

GREENHOUSE FILM CATEGORIES

At a greenhouse film, there is seldom used a light stabilisator system only. In most cases there
are used functional additives in addition for optimised crop production

:Frequently used features at greenhouse films are

UV-STABILISED 1ST TO 4TH GENERATION
These films are applied where there is little saving on heat inputs and where condensation is not
a problem

UV-STABILISED 1ST TO 3RD GENERATION / THERMIC FILMS

Formulated to improve heat retention by use of additional IR-Barrier additives. When using IRBarrier additives, the capability of the greenhouse film to reflect during night infrared radiation
back into the greenhouse directly saves energy losses, keeping the thermal energy inside

UV-STABILISED 1ST TO 3RD GENERATION / ANTIFOG / THERMIC FILMS

Have thermic properties by use of IR-Barrier additives and Antifog additives to control the
condensation of water on the film. If properly installed, water will condense uniformly on the film
transforming to a water film. This improves light transmission and reduces the risk of water falling
on plants. Best for crops which respond well to high direct light levels and warm temperatures

Please contact us to get dosage recommendations to your particular application

ANTIFOG ADDITIVES

ANTIFOG BASICS
The term fog is used to describe the condensation of water vapour on the surface of a transparent
plastic film in the form of small to large drop lets. The reason we see the water in the form of
condensed water drop lets on the surface of the plastic film is, beside humidity and temperature
differences, due to the difference between the surface tension of the water and the surface tension of
the polymer

The antifog additive is incorporated into the polymer matrix during the extrusion process. Upon
extrusion, the additive migrates to the surface of the polymer, where the additive is increasing the
surface tension of the polymer. A small quantity of the antifog additive dissolves in the water drop let
and decreases the surface tension of the water. At one point the surface tension of the polymer and
the surface tension of the water “ drop let” are equal so that the water drop let is spread into a
continuous layer of water, which is transparent

Using Antifog additives will improve light transmission of greenhouse films
:enabling following result s
higher plant grow rates
higher crop yield per plant
earlier crop maturity and hence the date it may be sold
will reduce burning of plants and crop spoilage
will reduce constant water dripping

It is imperative that select ed base polymers are free from slip additives! Regardless if Mono or COEX
film, use of any migrating slip additive can inhibit the Antifog effect totally down to zero, because of
contradictory functional effects to film surface! Use of Light Diffuser additives, Antiblock additives
based upon natural or synthetic silica, or mineral based IR Barrier additives, will deteriorate the
Antifog effect in a certain way, because these additives are able to adsorb on their particle surface
certain amounts of Antifog active substance itself. When such additives have to be used, the dosage
of the Antifog MB must be adapted in order to compensate the adsorption effect

At COEX films, the Antifog effect is considerably influenced by the choice of polymers in the
respective layers. Antifog MB’s use migrating additives, lower or no VA Copolymer content in the
chosen polymer slow down the migration property and/or the reservoir capability of the system itself
This is the reason why superior antifog effects can be achieved at speciality COEX films with right
polymer select ion corresponding to the layer build-up

Since the Antifog effect also depends to a big extent on the agricultural end use conditions inside and
around the greenhouse and should therefore be tested under practical conditions on geographical
area of application, before taking an antifog greenhouse film formulation on commercial scale

INFRARED (IR) BARRIER, BASICS

Radiation of long wavelength infrared energy can pass through the greenhouse film
At night, the warm plants, soil and components within the greenhouse loose energy by transmission
of long wave (infrared) radiation to the cold sky above. The rate of this loss depends, not only on the
temperature of the plants, and the atmospheric conditions (clouds, carbon dioxide, and ozone
content), but also on the properties of the greenhouse film cover material

The composition of the film, the polymer select ion and the use of suitable additives influence this
property significantly, and ensure by use of proper additives to keep the greenhouse warm inside at
night at cold seasons, enabling earlier cultivations in springtime's and prolonging cultivations at
autumn. Heat retention is achieved by choosing the correct polymers for the film or by using special
additives like IR Barriers. The thickness of the film will also have an effect - thinner films will tend to
give inside colder night-time and winter temperatures

When using IR-Barrier additives, the capability of the greenhouse film to reflect during night long
wavelength infrared radiation back into the greenhouse directly saves energy losses, keeping the
thermal energy inside

Amongst other methods, there are two main methods to give IR Barrier properties to LDPE
greenhouse films

Use of mineral IR Barrier additives in LDPE films especially, but not limit ed, applied for Monofilms
the thinner the film, the more addition rate is necessary

Use of ethylene-vinyl-acetate (EVA) copolymer, applied most often at COEX films, because EVA
has certain IR Barrier property by itself, in relation to VA content and thickness of the film

Greenhouse Films

All indications in this product information were elaborated for support and service to our customers
All data’s and statements in this product information have been obtained from laboratory tests under
ideal and closely controlled conditions. The information should act as a guide only and should not be
construed as guaranteeing specific properties or suitability for a particular application. Therefore
trials by customers using their polymers and their conditions must confirm the suitability of our
product for the intended application