General specifications of additives
Films without Anti-UV additive lose their features after a few months (4-6 months depending on the film thickness) and gradually tare or disappear. To achieve an acceptable durability, UV-Stabilizer additive must be added to the plastic film. Performance of the UV stabilizer additive depends on the product type, desired film lifetime, Climate, film thickness, and the type of greenhouse structure along with the type of crops.
When using sulfur and chlorine in greenhouse, a special UV stabilizer material must be used. Customers are required to notify the factory of any amounts of poly-Ag, chlorine, or sulfur uses in their greenhouse.
The IR additive in the plastic films reflects the infrared radiation from the sun, which makes the interior of the greenhouse warmer. Since the heated clay particles contained in the IR additive are very fine (about 1000/1 mm), the film surface is covered with a thin layer of clay and holds the IR light inside the greenhouse. Thus, causing the plastic film to get slowly warm or cool and balances the heat difference between day and night in the greenhouse. This effect does not decay over time, and these effects are within the film for as long as it is being used.
Infrared radiation can`t be seen with human eyes, but it can be felt by its by warmth. This radiation can easily penetrate and even reach the soil in foggy weathers. In winter, plants are at risk of frostbite in temperatures of up to 1 to 2 degrees Celsius. To prevent this issue, IR additive should be added to the plastic film. IR additives helps diffuse all the lights in the greenhouse homogeneously. This causes the greenhouse to reach maximum photosynthesis and plant growth rate.
Research has shown that IR additives increase this rate up to 20 to 30 percent. besides, directly transmitted light without proper diffusion will cause burns on plants and reduce product quality. The IR additive is added to the plastic film for better light diffusion in the greenhouse and to prevent the plants from burning.
To face frequent evaporations in greenhouses, tunnels, and under mulch films, caused by condensation, AntiFog additive is used. When the relative humidity is over 100, vapor condenses on the cooler plastic films. Most polymeric materials, such as greenhouse films, are not water-friendly and have low surface energy. Thus, when the plastic film touches with stacked vapor, the water droplets are formed on the surface of the film. The formed vapor inside the greenhouse causes incomplete light transmission into the greenhouse causing negative effects on the growth of greenhouse plants. It can also cause water droplets to settle on the surface of the plant and cause diseases. Anti-Fog additives prevent vapor formation and separates droplets of water on the inner surface of the greenhouse, allowing light to enter the greenhouse effectively.
6 percent of the sunlight that reaches the Earth has UV radiation. This radiation is particularly important and effective in raising crops. In addition to helping plants grow and improving vegetables and flower colors, this radiation is also important for avoiding plant diseases and insect behaviors. Most insects need UV radiation to navigate and view plants. The lack of UV radiation confuses insects. For plant extract, insects prefer to suck on plants, especially young leaves of flowers and vegetables.
If the UV radiation is blocked from entering the greenhouse by the additives used in our greenhouse films, the activities of several insects such as Thrips, Whiteflies, etc. are impossible. Due to the lack of UV radiation in the greenhouse, its areas become slightly dark and insects leave the greenhouse. Since the upper part of the greenhouse is very dark, insects cannot reach the upper areas where the young leaves of the plants are found. Plant leaves in the lower part are old and rough and are not suitable for insects. Since these insects cannot live in the greenhouse, they cannot infect the plant with the viruses and diseases that they carry by themselves. It has been proven that the additives in the greenhouse films protect plants and crops from the viruses that insects such as Whiteflies and Thrips carry by themselves. They are useful in controlling the fungal disease of plants and flowers too. Another use of these additives for the greenhouse is to prevent black spots on red flowers, causing a drop in the value for Rose flowers. But as mentioned earlier, plants also need UV radiation to grow. so, we shouldn’t block the entrance of UV radiation into the greenhouse completely. For example, some white roses need UV radiation to achieve the right shade color. In these cases, the use of additives should be minimal or not at all. At Shimi Plastic by using our experience and the latest knowledge and technologies, additives are selected with high precision and sensitivity so as not to block all UV radiations.
Nor Hals additive is a high-performance light stabilizer that in addition to preserving the plastic film’s life-span, It can especially protect the greenhouse plants from strong, light, and high-concentration chemicals. Shimi Plastic offers the following capabilities to its customers by adding the Nor Hals additives in its agricultural plastic films:
- Long-term protection against strong solar radiations
- Sustainable protection against build-up heat in the greenhouse
- High resistance to agricultural chemicals, even with elemental sulfur
- Suitable for integrated pest management (IPM)
- Providing optimum light for crops
- Reduce costs due to increased durability of our agricultural films