Technical Library

Choose a dye.
Understand the data. Verify the documents.

Nuchem's technical library helps buyers use the published COTFIX catalogue without confusing series selection, test data and approval scope. Start with the intended fibre, process and shade; compare the exact grade's reported table row; then verify the documents that apply to that product and strength variant.

Published 6 October 2026 · Technical review and release approval completed by Shravan Goyal, Director.

Start with the question you need to answer

Understand the data

Read fastness and solubility tables

Learn why each grade row and each column must be read separately, and what the catalogue cannot establish without the applicable method or lot record.

Read the guide
Choose a series

Compare eight COTFIX series

Compare the published process and shade positioning for VS, ME, HE, RGB, D, RR, Reactive Blacks and H/P Printing.

Compare the series
Verify documents

Check the exact grade

Keep GOTS input records, ECO PASSPORT certification and ZDHC Gateway conformance separate. Match exact names, variants, dates and conditions.

Verify product records

Three evidence levels

A catalogue row is a published product statement. A method or lot record explains how a result was produced for a defined sample. An approval record shows the scope of one named scheme. The library will identify which kind of evidence supports each explanation.

  1. Catalogue: use the row to shortlist a grade.
  2. Test or lot evidence: confirm method, conditions and applicable result.
  3. Approval record: match the exact product and conditions separately.

Need a grade-specific discussion?

Share the exact grade or target shade, fibre, process, required test standard and approval documents. Nuchem can then discuss the relevant product information without treating a series name as proof of performance or approval.

Send your requirement