Selecting Ink Based on Substrate Rather Than Price

Coding and printing consumables look like an easy line item to compare on unit price. Two cartridges look identical, one is 15 % cheaper, the procurement decision writes itself. In practice, ink is one of the smallest input costs in pharmaceutical packaging — and one of the highest-impact if it fails. Selecting ink against substrate rather than against headline price is the practice that separates lines that run reliably from lines that need constant intervention.

This article outlines why price-first buying tends to underperform, how to run a substrate-driven selection instead, and where a specialist supplier fits in the process. Axion Group supplies pharmaceutical printing, coding and production consumables as a specialist supplier.

Why price-first buying fails

The problem with pricing consumables in isolation is that the visible cost is small and the invisible costs are large. A cartridge that costs less per unit but fails an adhesion test on a specific substrate lot creates:

• Rework or scrapped batches
• Verification failures and line stops
• Investigation time from production and quality functions
• Customer complaints downstream

None of these costs are visible on the purchase order. They only appear when the failed batch is being investigated, and by then the "savings" from the cheaper cartridge are usually a rounding error.

A price-first shortlist also tends to homogenise consumables across substrates that behave differently — a single cartridge reference used across coated cartons, film labels, and blister foils, for example. That works until a substrate lot drifts and the standardised cartridge is no longer inside its intended application window.

Substrate-driven selection framework

A substrate-driven selection reverses the sequence. Instead of shortlisting cartridges by price and then trying them against the substrate, the substrate profile drives the shortlist. In practice:

1. Document the substrate profile for each coded packaging component — supplier, grade, lot variability, coating, and downstream process.
2. Group packaging components by substrate family (porous, non-porous, film, foil, glass).
3. Build a preferred shortlist of consumables against each substrate family, sourced from a small number of specialist supply partners.
4. Standardise within each substrate family; accept multiple SKUs across families where the chemistries need to differ.
5. Confirm each shortlist entry through an application trial before it is added to the approved-consumable list.

The output is a small, deliberate consumable set that is matched to the packaging portfolio.

Total cost of print quality issues

A useful exercise for teams making this shift is to look at the last twelve months of coding-related deviations and calculate the total cost. Typical categories include:

• Investigation hours (production + quality)
• Rework or scrap
• Verification-station stops
• Emergency consumable freight to plug a stock-out
• Consultant or supplier callouts

In our experience with pharmaceutical customers, the annualised cost of these events is often meaningfully higher than the entire ink and cartridge budget. That number is what a substrate-driven approach is protecting against.

Working with your ink supplier on evaluation

A specialist supplier's role in this process is not to sell more ink; it is to help structure the shortlist and the trials. Practical asks:

• Provide technical documentation for candidate products against the customer's substrate profiles.
• Support bench and short-production trials.
• Advise on retention samples and trial documentation.
• Support the change-control decision with an application review.

Axion Group works this way with pharmaceutical customers.

A practical checklist

Before your next consumables purchase, check that you can answer:

• Which substrate family does this cartridge belong to?
• What is the last-trialled substrate lot for this cartridge?
• What is the trial documentation reference?
• What is the alternative cartridge on the approved-consumable list, and when was it last trialled?

If the answers are missing or informal, the consumables list is being managed on price. If the answers are available and current, the list is being managed on suitability. Product suitability is always subject to application testing under the customer's actual production conditions.