What is a lab dip in fashion?
A small fabric or yarn sample dyed by a mill to show how closely it can match the brand's colour standard before bulk dyeing.
In short
A lab dip is a small swatch of fabric or yarn dyed in a laboratory to show how closely a mill can match a brand's colour standard on a particular material. The brand compares it with the standard, approves it or requests corrections, and only then can bulk dyeing begin.
How does it work in practice?
After receiving the colour standard and fabric details, the mill's lab develops a dye recipe and dyes small samples, often submitting two or three variations labelled A, B and C. The brand's colour or quality team checks them visually in a light booth and, increasingly, with a spectrophotometer. The result is one of three outcomes: approved, approved with comments, or rejected with directions such as "slightly redder" or "too dark".
- Each fabric quality needs its own lab dip, even for the same colour
- Trims such as zips and thread are matched separately
- Approved dips are kept as references for bulk inspection
Why does it matter for fashion businesses?
Lab dip approval sits on the critical path of the production calendar. Repeated rejections can delay bulk fabric and push a delivery outside the agreed delivery window, which affects wholesale customers and in-season sell-through. A disciplined process with clear comments keeps the number of rounds low and protects lead times.
How is AI changing it?
Colour matching software and machine learning models can predict dye recipes from spectral data and past results, so the first submission is more likely to pass. Some brands approve dips digitally from measured values, reducing courier time. Computer vision is also used to compare bulk rolls against the approved dip during inspection.
Common pitfalls
Common issues include approving dips on the wrong base fabric, ignoring how finishing processes change shade, and not checking under all agreed light sources. Another risk is approving a dip that the mill cannot reproduce consistently in bulk, which only shows up once production lots arrive.
Frequently asked questions
How long does lab dip approval take?
Timing varies by mill, fabric and the number of correction rounds needed. Digital approval from spectral data can shorten the process compared with shipping physical swatches back and forth.
Do trims also need lab dips?
Yes. Zips, buttons, thread and labels are dyed or coloured separately and need their own matching to the colour standard so the finished garment looks consistent.
