What is the Natural Ultraviolet light? Light Stabilizers? Anti UV mastertbatch?

What is the Natural Ultraviolet light?

Natural Ultraviolet light refers to ultraviolet radiation from the sun with wavelengths between 100–400nm, serving as the only natural source of UV rays on Earth's surface.As it passes through the atmosphere, it is partially absorbed or scattered. The Ultraviolet light that ultimately reaches the ground consists primarily of UVA, a small amount of UVB, while UVC is almost entirely blocked by the ozone layer.

Based on wavelength, penetration power and biological/chemical effects, natural ultraviolet light is classified into three categories:

1. UVA (315 - 400 nm)

2. UVB (280 - 315 nm)

3. UVC (100 - 280 nm)

1. UVA (315 - 400 nm)

Alternative name: Long-wave ultraviolet radiation, "black light".

Characteristic:

The penetration power is the strongest, capable of penetrating clouds and glass (ordinary windows cannot completely block it).

The proportion reaching the ground surface is approximately 95%, and the intensity remains relatively stable

Impact on plastic products: Slowly degradable plastics, coatings and other outdoor plastic products.

2. UVB (280—315 nm)

Alternative name: Medium-wave ultraviolet rays. 

Characteristic:

Approximately 5% reaches the surface, with the majority being absorbed by the ozone layer.

Intensity varies with seasons and time (strongest at midday in summer, weaker in winter). 

Impact on plastic products: accelerates rubber aging, paint flaking.

3. UVC (100 - 280 nm)

Alternative names: Short-wave ultraviolet, germicidal ultraviolet.

Characteristics: Nearly 100% absorbed by the ozone layer and oxygen, not reaching the surface under natural conditions.

What is the light stabilizers?

Light stabilizers are chemical additives primarily used to protect materials (especially polymers) from degradation caused by ultraviolet (UV) radiation or other light exposure. They work by absorbing, scattering, or converting UV energy, inhibiting photo-oxidation reactions, thereby extending material lifespan and maintaining physical properties and appearance stability.  

Main Types of Light Stabilizers:

1. UV Absorbers (UVA)

   - Absorb UV light and convert it into harmless heat, reducing material damage.  

   - Common types: Benzotriazoles (e.g., Tinuvin), benzophenones (e.g., Chimassorb), triazines.  

2. Hindered Amine Light Stabilizers (HALS)

   - Do not absorb UV directly but interrupt photo-oxidation by scavenging free radicals (e.g., peroxy radicals).  

   - Highly effective for long-term outdoor exposure (e.g., plastics, coatings).  

   - Examples: Tinuvin 770, Chimassorb 944.  

3. Quenchers

   - Dissipate energy from excited molecules (e.g., chromophores in polymers) via energy transfer, preventing degradation.  

   - Mainly used in films and fiber products.  

Related:

What Are Anti UV Masterbatches?