Lot-to-lot shade variation in printed fabrics is controlled by fixing every variable that affects colour before the second lot starts: an approved strike-off kept as the standard, the same screens or print files, the same greige and dye recipe, lab dips for ground colours, a written tolerance in the contract and a first-roll check before the run continues. Shade drift rarely has a single cause.
It usually comes from a change of greige, a new dye batch, re-engraved screens, or a print house that has simply not been asked to match the last lot. Each of these is cheap to control in advance and expensive to argue about afterwards.
Fix the standard first
Approve a strike-off on the actual production greige, not on a substitute, and view it in a light box under an agreed illuminant, usually D65 with a secondary store light. Cut the approved strike-off into sealed, signed pieces: one for you, one for the print house and one for your agent in Surat.
When the first lot is produced, keep a piece from the approved first roll as the production standard alongside the strike-off. Later lots are matched to this piece, which prevents a slow drift where every lot is matched to the previous one rather than to the original.
Controls for every repeat lot
- Greige: the same supplier, construction and pretreatment, with heat setting at the same temperature, since a different base changes colour yield.
- Screens or files: the same rotary screens stored and recorded, or the same digital files and printer profile, with any re-engraving approved against the standard.
- Recipe: the dye or pigment recipe recorded on the lot card, with the same dye brands and batch control, and the same fixation and washing conditions.
- Ground colour: a lab dip approved against the standard before each lot, not reused from memory.
- First-roll check: the first roll compared with the standard in the light box and signed off before the rest of the lot is printed.
- Roll grouping: rolls marked by shade group so the receiving warehouse can keep garments cut from one group.
What to put in the contract
State the tolerance either as a visual grey scale grade or as a colour difference limit measured on a spectrophotometer, and name who judges it and under what light. Say what happens when a lot falls outside tolerance: re-dye, discount, or rejection, and whether the supplier may ship shade-sorted rolls with a lower tolerance within each group.
Require that the lot card and the standard are kept for a stated period so a repeat order next year starts from the same point.
How we help with shade
We hold the sealed standards in Surat, sit in on strike-off and first-roll approvals at the process house, and send samples to a NABL-accredited lab when a measured colour difference is needed. Rolls are checked against the standard before loading and you receive a weekly update with light box photographs. A free 20-minute sourcing review is a good moment to set up these standards before a repeat programme begins.