Understanding the Difference Between High Light Fastness Color Masterbatches and Anti-UV Additive Masterbatches

In the world of plastic manufacturing, especially in applications exposed to sunlight such as outdoor furniture, agricultural films, packaging, or automotive parts, maintaining color stability and surface integrity is crucial. However, a common misconception exists in the industry: many believe that using anti-UV masterbatches automatically ensures long-term color durability. This, however, is not entirely true.

To clarify, color fading and plastic degradation are two separate challenges, and each requires a specific solution.

1. What Are High Light Fastness Color Masterbatches?

High light fastness color masterbatches are specifically designed using pigments that have excellent resistance to fading when exposed to light, particularly UV radiation from sunlight. The light fastness of a pigment refers to its ability to retain its original color and strength over time without significant fading. These pigments are tested according to international standards (such as the Blue Wool Scale) and are selected based on the intended application—whether it’s indoor, outdoor, short-term, or long-term exposure.

So, if your goal is to preserve the color vibrancy of your plastic product under UV exposure, choosing a masterbatch with a high light fastness rating is essential.

2. What Are Anti-UV Additive Masterbatches?

Anti-UV masterbatches contain UV stabilizers or UV absorbers that are added to the plastic to protect the polymer itself from degradation. UV exposure can break down the molecular structure of plastics, causing yellowing, cracking, chalking, and loss of mechanical strength. Anti-UV additives work by either absorbing harmful UV rays or neutralizing the free radicals that form during UV exposure.

However, these additives do not protect the pigments used for coloring. Their main role is to protect the plastic matrix, not the color.

3. Why Using Only Anti-UV Is Not Enough for Color Durability

Many manufacturers mistakenly believe that simply adding anti-UV additives will prevent color fading. While UV stabilizers can prolong the life of the plastic, they do not prevent the pigment from fading unless the pigment itself has high light fastness properties.

For example, a low-quality pigment may still fade significantly over time even if the plastic is UV-stabilized. This can lead to disappointing results where the product remains structurally sound, but its appearance deteriorates rapidly.

4. The Right Approach: A Combination Strategy

For outdoor and sun-exposed applications, the best results come from a combination of both high light fastness pigments and anti-UV additives. This dual approach ensures:

• The color remains vibrant and resistant to fading.

• The plastic stays strong, flexible, and free from surface damage caused by UV exposure.

  
  

5. Conclusion

Understanding the distinct roles of color masterbatches and additive masterbatches is key to producing long-lasting, high-quality plastic products. At Corbi Polymer, we help our customers choose the right combination of masterbatches for their specific needs—ensuring that both color durability and material integrity are achieved.

Avoid the common mistake. If color stability matters for your product, don’t rely solely on UV protection—always choose high light fastness color masterbatches in addition to anti-UV additives.