Sample & Quotation Request Guide for Ink Systems & Formulation

What Symptoms in Your Current Ink Quote Process Are Costing You Sample Rounds #

When buyers come to us with a new ink system requirement, the briefs we receive fall into roughly three categories: complete, partial, and “I’ll send more details later.” Partial and deferred briefs are the direct cause of at least 60% of the sample iterations we log under our QC-07 resampling tracker each quarter. Recognising the symptoms early saves two to four weeks.

Here are the observable failure patterns and their most likely root causes:

A brief that causes any of the above isn’t a communication problem. It’s a specification gap that our formulation team cannot bridge without your input.

The Root Cause Most Teams Misdiagnose: Substrate Surface Energy, Not Ink Colour #

When a printed sample comes back looking “wrong,” the default assumption is that the ink colour was mixed incorrectly. In roughly two-thirds of the cases we see, the colour is fine. The adhesion is not.

Surface energy is measured in millinewtons per metre (mN/m). For ink to wet out and bond to a plastic film substrate, the substrate’s surface energy must exceed the ink’s surface tension by at least 6–8 mN/m. Untreated polyethylene typically reads 31–34 mN/m. Untreated BOPP sits at 29–32 mN/m. Standard water-based flexo inks have surface tensions in the 28–34 mN/m range. At that overlap, adhesion is marginal at best and will fail a 180° peel test per ASTM D903 under any meaningful load.

Corona treatment raises surface energy to 38–44 mN/m on BOPP, and that 10+ mN/m gap is what creates reliable adhesion. But corona treatment degrades. A film treated at the film manufacturer and then stored for six weeks can drop back to 36 mN/m or lower, depending on humidity and how it was wound. By the time the reel arrives on our press, the effective surface energy may or may not be above threshold.

The confirmation method is a simple dyne test using calibrated dyne pens (or dyne solution per ISO 8296) applied at the press feed. We run this test on every incoming flexible film reel as part of our incoming inspection protocol. If dyne level reads below 38 mN/m, the reel goes on hold. If a buyer’s brief says “BOPP, unspecified treatment,” we cannot predict which outcome the material lot will produce — so our sample is essentially a guess until the actual production reel is tested.

The measurement is fast, takes under 60 seconds per reel, and costs nothing beyond the dyne pens. But without the substrate spec in the brief, we can’t call out the risk before the sample is made.

Corrective Actions, Ranked by Impact on Getting an Accurate First Sample #

1. Specify substrate by grade, treatment, and thickness. For film substrates, include: film type (BOPP, CPP, PE, PET), treatment status (corona/untreated/metallised), gauge in microns (common flexo film runs 12–25 µm for inner layers, 30–60 µm for surface print). This single change eliminates the most common resampling trigger. Applies to both flexo and gravure ink briefs.

2. Provide a Pantone reference or Lab colour target with Delta-E tolerance. If you need colour matched to an existing product, specify the allowable Delta-E. For premium consumer goods, Delta-E ≤ 1.5 is the right threshold. For standard commercial printing, Delta-E ≤ 3.0 is typical. Without this number, “match our brand blue” requires at least two proof iterations regardless of how experienced the formulator is.

3. Declare the end-use application and any compliance requirements. If packaging is food-adjacent (e.g., outer wrap, not direct contact), state that explicitly. If FDA 21 CFR Part 175 or EU 10/2011 migration limits apply, we need to select low-migration photoinitiators and resins from the qualified list before sampling, not after. This step cannot be added retroactively without reformulation.

4. Request a white sample before a printed proof. For structural formats (pouches, sleeves, labels), a white sample (unprinted, correct construction and material) lets you confirm dimensional fit, peel force, and substrate compatibility before spending budget on colour-accurate proofs. Printed proofs cost 3–5× more to produce than white samples; confirming structure first keeps total sampling cost down.

5. Submit quantity tiers at RFQ stage. Ink system pricing depends heavily on batch size. A 25 kg ink batch for a 20,000-unit trial run prices differently from a 200 kg batch for a 200,000-unit production order. If you submit only one quantity, our quote will carry a caveat that pricing could change by 10–20% at a different volume. Give us three tiers — your trial quantity, your standard reorder, and your peak order — and we can lock pricing on all three in the initial quote.

Prevention: What to Put in the Brief Before You Request a Quote #

For ink system quotations, the spec sheet we need before our formulation team can issue a firm price covers: substrate identity (type, grade, treatment, gauge), print process (flexo/gravure/offset), number of colours and whether white is a base layer, desired finish (gloss/matte/tactile), end-use compliance tier (standard/food-adjacent/direct food contact), artwork file in CMYK-separated PDF with 3 mm bleed and Pantone call-outs, and your Delta-E acceptance threshold.

The single brief gap that triggers the most resampling iterations is missing the compliance tier. Brands often assume that food-adjacent packaging doesn’t require low-migration ink, but if outer packaging contacts unpackaged food even briefly in a retail environment, retailers in the EU may require compliance with EU 10/2011 limits on primary migrants.

Request our Ink Brief Template (form ref: IBT-04) at the start of any new project. It takes 20 minutes to complete and eliminates the back-and-forth that typically adds 10–15 working days to a first-sample cycle.

Specification Notes for Brand Partners #

When you brief us on an ink system requirement, the most useful information arrives in this order: substrate confirmed, process confirmed, compliance tier declared, colour targets specified. That sequence lets us assign the correct ink family before any other work begins.

The gap we see most often in new briefs is an unspecified lamination structure. If the ink layer will sit between two films in a laminate, the ink must withstand the lamination adhesive chemistry — and if solvent-based adhesive is used, the ink must be solvent-resistant. We’ve had briefs where this wasn’t flagged, and the laminated sample showed ink bleed at the bond line. Specifying the full layer structure (print / adhesive type / laminate film) upfront avoids this entirely.

Our standard sampling timeline for ink formulation and a printed proof is 12–15 working days from confirmed brief. Complex compliance formulations (low-migration UV, food-direct water-based systems) run 18–22 working days due to migration screening. Timeline resets to day one if the substrate changes after sampling begins — which is the main reason to confirm substrate before issuing a sample order.

What artwork file format do you need for an ink formulation and proof request?

PDF/X-1a or PDF/X-4, CMYK-separated, with all Pantone colours called out by PMS number. Minimum 300 dpi at final print size, with 3 mm bleed on all live edges. RGB files require colour conversion on our end, which introduces colour shift — a Delta-E difference of 2.0–4.0 is common in RGB-to-CMYK conversion without a calibrated ICC profile provided by the client.

How many sample stages should I budget for before production approval?

For a straightforward brief with substrate and compliance tier confirmed upfront: white sample (5–7 working days), printed colour proof (7–10 working days), and production sample (tied to first production run). That’s three stages. Where we see four or five stages is typically when the substrate is changed after proofing begins, or when compliance requirements are added mid-process.

Can I compare quotes from two suppliers using different ink systems?

Yes, but compare on total cost per thousand units, not ink cost per kilogram. A high-solid water-based ink at a higher kg price may require less laydown per square metre than a lower-solid system, which changes the per-unit cost significantly. Ask both suppliers to quote on identical ink laydown figures (in g/m²) if you want a valid comparison. Without a common laydown spec, kg price comparisons are not reliable.

Does the print process affect how I brief the ink specification?

The ink viscosity range for flexo runs 15–25 seconds (Zahn cup #3), while gravure inks run 12–18 seconds — and offset inks are specified by tack value (typically 10–16 on the Inkometer scale) rather than viscosity. These are not interchangeable specifications. If you’re moving a job from gravure to flexo, the ink system needs to be reformulated from the base resin up, not simply diluted. State the print process clearly in the brief, and if you’re evaluating a process change, flag it as a separate qualification step.

What Delta-E tolerance should I specify for brand colour matching?

It depends on the packaging end-use and retail channel. Premium beauty and luxury goods: Delta-E ≤ 1.5 against a confirmed physical standard. Standard FMCG retail: Delta-E ≤ 3.0 is commercially acceptable. For colour that will appear across multiple packaging formats (carton, pouch, label), align all suppliers to the same physical colour standard — digital references alone will drift between substrates. If you don’t specify a tolerance, we default to Delta-E ≤ 2.0 under D50 illuminant per ISO 13655.

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Planning a packaging project? Contact our team to request a complimentary specification review and sample quote.

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