Short answer
Because part of the cost of a colour is fixed per batch: the material needed to flush the previous colour out, the set-up and the approval. One laboratory study measured 3.2 to 6.3 kg of plastic used to clean one small injection mould between colours. Suppliers turn that into terms. One powder-coating maker's quick-match service sells custom colours only in 55 lb packs, with a minimum of 55 lb and a maximum of 385 lb. No neutral source tabulates minimum orders for masterbatch or dyed textiles.
Every process that changes colour has to get the old colour out first, and the amount to be removed depends on the machine, not on the size of the order. A peer-reviewed study at the Budapest University of Technology and Economics measured it for injection moulding. Changing from blue to uncoloured ABS on a mould with a two-nozzle hot runner consumed 6.3 kg of material when the injection unit and hot runner were cleaned together, and 3.2 kg when the injection unit was purged first and the hot runner afterwards. The authors describe colour changeover as a poorly controlled procedure associated with high additional costs, a large amount of material and extended downtime. Whether the order is for a hundred parts or a hundred thousand, those kilograms and that downtime are spent once. On a short run they are a large part of the job; on a long one they vanish into the unit cost.
The study's figures belong to one machine, one mould and one colour pair. A dark-to-light change on a larger machine will take more; the point is that the quantity is fixed per change.
A minimum order is the commercial form of a fixed batch cost. Axalta's brochure for its ReplaShade service, which matches and makes a custom powder-coating colour in ten days, shows the shape of the bargain. The product comes in increments of 55 lb, with a minimum order of 55 lb and a maximum of 385 lb, and shipments may vary by 10% either way. The service is limited to certain polyester chemistries and to smooth, fine-texture and wrinkle finishes; special properties are excluded. Each restriction keeps the small batch cheap to make: standard resin systems, one pack size, a tolerance on quantity so that a batch need not be topped up. The brochure describes one supplier's fast small-lot service in 2015. Ordinary custom batches, and other suppliers, will have their own minimums, and nobody collects them.
Small coloured batches also lose economies that long runs take for granted. The EU reference document notes that in furniture coating, where colour changes are frequent, overspray cannot be recovered and reused as it can on long runs of one colour. It records that equipment for mixing two-component paint on demand, which avoids making more of a colour than the job needs, cost 9,000 to 18,000 euros for a mechanically driven unit on 2006 data, and that payback is normally several years for companies coating small series. In printing it lists decreasing print volume among the things that raise ink and solvent consumption per unit of product. In each case the small order pays a larger share of something that does not shrink with it: a clean-down, a piece of equipment, a make-ready.
The way round a minimum is to put the colour in at the last possible moment, so that the batch made in bulk is colourless or white. Decorative paint is the familiar case: the factory makes a few tint bases in volume and the shop adds concentrated tinters to a single tin, so the minimum order for a colour is one tin. The principle and its price are set out on the page about how many colours a firm can stock. Plastics masterbatch works in a similar way one step upstream, with the moulder dosing a colour concentrate into natural resin, and a car body takes its colour only at the base coat. Where the colour cannot be added late — a dyed yarn, a through-coloured compound, a factory-finished coil — the supplier's batch size becomes the buyer's minimum.
This page stops short of the question most buyers actually have, which is what the minimum will be. No trade body or official source tabulates minimum order quantities, lead times or small-lot surcharges for custom-coloured masterbatch, dye lots, coil-coated metal or factory-tinted paint. Individual suppliers state their own terms, and those vary with the machine, the colour and how much the supplier wants the business. Colourwise has not compiled them, because a list of advertised minimums would be neither complete nor stable. The measured study and the reference document explain why a minimum exists and what it is made of. For the number, the only reliable source is the supplier's quotation for the colour in question, and it is worth asking what the same colour would cost at twice the quantity.
| What it concerns | Colour or finish factor | Published figure | Where and when | Kind of evidence |
|---|---|---|---|---|
| Colour change at one sprayer in a vehicle paint shop | Any change of base coat colour | 200 ml of rinsing agent per colour change per sprayer | European Union; 2013 guideline values, published 2020 | Measured cost |
| Colour grouping (block painting) of car bodies | Sequence of colours through the booth | 2 to 6 bodies per colour group | European Union; Information exchange to 2018; published 2020 | Documented industry practice |
| Colour changeover in a hot-runner injection mould | Blue ABS to uncoloured ABS | 3.2 to 6.3 kg of ABS to clean the system | Laboratory, Budapest; 2022 | Measured cost |
| Spray coating of furniture | Frequent colour changes on short runs | No figure published | European Union; Information exchange to 2018; published 2020 | Documented industry practice |
| Custom colour-matched powder coating | A colour outside the stock range | 55 to 385 pounds per order (minimum to maximum) | North America; Brochure dated 2015 | Documented industry practice |
| Online mixing of two-component paint for small series | Many colours made in small quantities | 9,000 to 18,000 euros for a mechanically driven installation | European Union; 2006 data | Measured cost |
| Heatset web offset and flexible-packaging printing | Short runs | No figure published | European Union; Information exchange to 2018; published 2020 | Documented industry practice |
| Custom-coloured plastics masterbatch and dyed-to-order textiles | A colour made to order | No figure published | Not specific; Searched October 2026 | Colourwise interpretation |
Each statement is labelled by kind — established fact, a standard’s requirement, observed market data, a convention, or Colourwise’s own interpretation or analysis — with the strength of the evidence behind it.
FactStrong evidence
A laboratory study measured 6.3 kg of ABS used to clean a two-nozzle hot-runner injection mould after a change from blue to uncoloured material when the injection unit and hot runner were purged together, and 3.2 kg when they were cleaned separately.
Caveat: One machine, mould, polymer and colour pair; not a general figure for injection moulding.
Source: Developing a method for evaluating color changeover in a hot-runner multi-cavity injection mold
ConventionModerate evidence
Axalta's ReplaShade custom powder-coating service is supplied in 55 lb increments with a minimum order of 55 lb and a maximum of 385 lb, with colour matches produced in ten days excluding shipping.
Caveat: One supplier's brochure for a quick small-lot service, dated 2015; not an industry minimum and possibly superseded.
Source: ReplaShade custom color match and make service (brochure)
FactStrong evidence
The EU reference document gives investment costs of 9,000–18,000 euros for a mechanically driven online mixing installation for two-component products (2006 data) and says payback is normally several years for companies coating small series.
Caveat: 2006 prices; the document says payback depends on waste prevented, material prices and disposal costs.
FactStrong evidence
The same document states that reuse of overspray is not possible in short production runs with frequent colour changes, as often occur in furniture manufacturing.
Colourwise interpretationLimited evidence
A minimum order for a custom colour reflects costs that are fixed per batch — purge material, clean-down, set-up and approval — and so falls as a share of the job as the run lengthens.
Based on: Colourwise's reading of the measured moulding study, one supplier's published terms and the EU reference document's statements about short runs.
Caveat: No neutral dataset of minimum orders exists to test it against, and commercial factors also set minimums.
Reviewed 6 October 2026. Colourwise summarises its sources in its own words and does not reproduce standards text or proprietary colour data. Spotted an error? Tell us.