Optical Brightener Masterbatch — Recycled or Off-White Plastic Looks Yellow or Dull

1. Problem

Recycled resin or off-spec white looks yellow or gray on the finished part, and the customer wants a cleaner, whiter appearance without going to full white pigmentation.

2. Symptoms

• Yellow cast on recycled PET, PP, or PE
• Dull or gray tone in transparent parts
• Batch-to-batch color drift toward yellow
• Poor visual match to virgin resin

3. Investigation (Before Prescribing an Additive)

• Confirm the base color problem — yellowing (recyclate), thermal degradation, or contamination.
• Check whether the goal is neutralization (bluing) or actual brightening (fluorescence).
• Check whether the part is UV-exposed — some optical brighteners degrade quickly outdoors.
• Confirm food-contact and regulatory environment.

4. Candidate Masterbatch Family

One family commonly evaluated is Optical Brightener Masterbatch — fluorescent whitening agents (typically stilbene- or benzoxazole-based) that absorb UV and re-emit blue-white light, visually neutralizing yellow tones. Often combined with a small amount of blue pigment ('bluing') for stable perceived whiteness.

5. Polymer Considerations

Compatible with most commodity and engineering resins at low loadings.

7. RFQ Mini Technical Specification (9 Fields)

Under Application-First Selling v1.0 and Problem-First Discovery v1.

Continue Your Path

• Submit RFQ → /quote