WEATHERING

Weatherability is the strength of materials against various climate / weather / environmental factors.

A variety of climate parameters are as follows.
• Sunlight (UV light, infrared light, visible light)
• Temperature
• Moisture (rain, dew, humidity)
• Contaminants (acid rain, ozone, NOx)
• Other: Typhoon, Yellow Sand Dust, Fine dust
• In the case of plastic products, cleaning agents, disinfectants, fungicides, insecticides, etc., which come into contact with the application, also play a role in influencing weatherability.

UV light is contained in the sun’s rays and reaches the surface of the earth and has the following characteristics.
• Wavelength: 10-400 nm, shorter wavelength than visible light and longer
wavelength than X-ray.
• It accounts for approximately 5-10% of total solar energy emission.
• UV light energy is 70-100 Kcal / mole.
• Decomposes plastics, paints, and coating materials to deteriorate appearance and
properties, and shortens product value in a short period of time.
• Tanning, summer An image of the iron exposed area is caused by overexposure
to UV light.
• Short wavelengths below the UV-C range are completely absorbed by the ozone
layer and the atmosphere layer.
• The UV-B region is mostly absorbed in the ozone layer.
• The wavelengths of the UV-A region reach the Earth and damage the plastic,
paint and our skin with powerful energy.
• Plastics that have been exposed to UV-A for a certain period of time will be
damaged, lose their physical properties, break or shrink, and oxidize the surface.
• Sunscreen cosmetics to protect the skin are a typical application of UV absorber,
which protects the skin (biopolymer) by absorbing and blocking UV light before
reaching the skin.
• Light stabilizer (UV stabilizer) and light absorber (UV absorber) are eco-friendly
additives that protect plastic, coating and paint from strong UV light to prevent
aging and increase the service life.