Chrome-free pigment matching data for LDPE plastic applications
Chrome-free pigment alternatives that match the shade, performance, and cost of traditional chrome-based colorants in LDPE plastic applications — with side-by-side evaluation data.
Chrome-based pigments (like Lead Chromate and Molybdate Orange) have long been the industry standard in plastic applications for their strong, bright, opaque shades. But rising environmental and regulatory pressure around heavy metals has pushed the industry toward chrome-free alternatives. Here's how three chrome-free matches performed against their chrome-based counterparts in LDPE.
1. Sudadur Orange 1475 (PR 104) → Chrome-Free Match
Chrome-Free Formulation:
| Pigment & Additive | C.I. Name | % By Weight |
|---|---|---|
| Sudacolor Orange 212 | PO 34 | 0.30 |
| Titanium Dioxide (R104) | PW 6 | 0.05 |
| Polymer & Additive | -- | 99.65 |
Evaluation Report:
| Characteristics | Sudadur Orange 1475 (Standard) | Chrome-Free (Sudacolor Orange 212) |
|---|---|---|
| Color Shade Full Tone (ΔE) | Standard | 2.40 |
| Relative Cost vs. Chrome Base | 1 | 2 |
- Chrome matching: Sudadur Orange 1475 at 0.5% pigment loading
- Chrome-free matching: Sudacolor Orange 212 at 0.3% pigment loading + 0.5% TiO2
2. Sudadur Yellow 1222K (PY 34) → Chrome-Free Match
Chrome-Free Formulation:
| Pigment & Additive | C.I. Name | % By Weight |
|---|---|---|
| Sudacolor Yellow 165 | PY 13 | 0.07 |
| Titanium Dioxide (R104) | PW 6 | 0.10 |
| Polymer & Additive | -- | 99.83 |
Evaluation Report:
| Characteristics | Sudadur Yellow 1222 (Standard) | Chrome-Free (Sudacolor Yellow 165) |
|---|---|---|
| Color Shade Full Tone (ΔE) | Standard | 2.13 |
| Relative Cost vs. Chrome Base | 1 | 1 |
- Chrome matching: Sudadur Yellow 1222K at 0.5% pigment loading
- Chrome-free matching: Sudacolor Yellow 165 at 0.07% pigment loading + 1.00% TiO2
3. Sudadur Yellow 1322K (PY 34) → Chrome-Free Match
Chrome-Free Formulation:
| Pigment & Additive | C.I. Name | % By Weight |
|---|---|---|
| Sudafast Yellow 137K | PY 83 | 0.07 |
| Titanium Dioxide (R104) | PW 6 | 0.10 |
| Polymer & Additive | -- | 99.83 |
Evaluation Report:
| Characteristics | Sudadur Yellow 1322 (Standard) | Chrome-Free (Sudafast Yellow 137K) |
|---|---|---|
| Color Shade Full Tone (ΔE) | Standard | 3.9 |
| Relative Cost vs. Chrome Base | 1 | 1 |
- Chrome matching: Sudadur Yellow 1322K at 0.5% pigment loading
- Chrome-free matching: Sudafast Yellow 137K at 0.07% pigment loading + 1.00% TiO2
Key Takeaways
- Chrome-free alternatives can achieve close shade matches (ΔE between 2.1–3.9) to standard chrome-based pigments in LDPE.
- Both yellow chrome-free matches came in at equal relative cost to the chrome base, while the orange chrome-free match cost roughly double.
- TiO2 (Titanium Dioxide) is used alongside the organic pigment in each formulation to help achieve opacity and shade matching at much lower pigment loadings than the chrome-based standard.
Source: Sudarshan Chemical Industries, Chrome Replacement – Plastic Application, 17th Dec 2012