---
type: faq
title: "Why did my colors print differently than the proof I approved?"
description: "Heavy ink coverage needs high curing heat, which can warp plastic and synthetic stocks and shift colors, so report a problem fast with photos."
resource: https://www.4over4.com/faqs/color-ink/why-did-my-colors-print-differently-than-the-proof-i-approved
tags: ["Printing Terms Glossary", "faq"]
generated:
  by: "process:4over4-mapp-build"
  at: 2026-10-20T21:01:19.542Z
timestamp: 2026-10-20T21:01:19.542Z
sources:
  - resource: https://www.4over4.com/faqs/color-ink/why-did-my-colors-print-differently-than-the-proof-i-approved
    title: "Why did my colors print differently than the proof I approved?"
status: stable
---

# Why did my colors print differently than the proof I approved?

Color can shift on press even after you approve a proof, most often because of the heat used to cure ink during printing. Designs with heavy ink coverage need high heat to cure the ink. On plastic and synthetic stocks, that heat can warp the material and shift colors. This behavior is difficult to control on press and is a known limitation of some stocks. If an order arrives with a noticeable color problem, report it to your printer promptly with photos showing the issue.

Heavy ink coverage needs high curing heat, which can warp plastic and synthetic stocks and shift colors, so report a problem fast with photos.

[Order Plastic Business Cards](https://www.4over4.com/product/plastic-business-cards)

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