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        # Perfect Color Every Time: Masterbatch Selection for PVC Products

        

**Topic:** Technical

        

Your client ordered 'Royal Blue' PVC pipes. The first batch was perfect. The second batch looks like 'Faded Denim'. They're both supposedly from the same masterbatch lot. What happened?

        
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## Problem

Color inconsistency in PVC is rarely a pigment problem alone  -  it's a system problem. The shade of the final product is influenced by: the base resin color (which varies between suppliers), stabilizer type (lead gives different undertones than Ca-Zn), processing temperature (higher temps shift hues), and filler loading (CaCO3 dilutes color intensity). Changing any one variable, even slightly, changes the final color. This is why factories that switch resin suppliers often face sudden color drift.

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## Likely cause

This issue often stems from inconsistent compounding temperatures, inferior raw material purity, or unbalanced stabilizer ratios within the formulation matrix.

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## Corrective direction

NBT supplies **pre-tested pigment masterbatches** designed for PVC systems. Our lab formulates each color recipe against a standard reference panel, accounting for the specific resin, stabilizer, and filler system that the client uses. For whites, our **high-purity Rutile TiO2** provides maximum opacity and brightness with minimal dosing (4-6 PHR). For dark colors, our Carbon Black masterbatch ensures jetness without compromising thermal stability. Every masterbatch lot is accompanied by a color measurement report (L*a*b* values) so you can verify consistency batch to batch.

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          ## Frequently Asked Questions

          
### Why does my white PVC turn pinkish after extrusion?

This is usually caused by the heat stabilizer reacting at high temperatures. Switch to a Tin-based or Ca-Zn stabilizer system for better initial color hold.

### Can outdoor PVC products maintain color for 10+ years?

Yes, with the right combination of UV-stable pigments, HALS stabilizers, and sufficient TiO2 loading. Organic pigments fade faster than inorganic ones in UV exposure.

        
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By NBT Technical Desk · Updated 2026-06-07

        

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