100Module 13 of 15
Print Methods 101
Offset, flexo, gravure, digital—strengths, limitations, economics, and best-use cases. Includes dry offset for cans.
8 minutes
printLesson Video
Print Methods 101
Module Content
1) Executive Summary
Top insights
- Right process, right job. Offset and flexo handle most retail packs; gravure dominates ultra‑long film runs; digital wins short runs/VDP. Cross‑over points are local—treat rules of thumb as regional. Evidence gap: comparable, current cross‑over datasets by category/region.
- Standards do the heavy lifting. PDF/X for exchange, ISO 19593‑1 for Processing Steps, and ISO/IEC 15416/15415 for barcode quality underpin predictable outcomes. [1–5]
- Beverage cans are a special case. Dry‑offset letterpress with spot inks; practical max ~120 LPI; dot gain ~20–30%; reverse traps and overlap management are essential. [6–7]
- Compliance is shifting. PPWR adopted; UK EPR eco‑modulation from 2026–27; France bans mineral‑oil inks from 1 Jan 2025 (MOAH/MOSH). [8–11]
- Design for recyclability is print‑sensitive. APR/CEFLEX/OPRL call out inks, coverage, and label/adhesive choices that hinder sortation/de‑inking. [12–14]
Immediate actions for design teams
- Standardize source files to PDF/X‑4 or PDF/X‑6; attach dielines/varnish layers via ISO 19593‑1. [1–2]
- Lock barcode specs to GS1 + ISO/IEC 15416/15415 and proof on the actual substrate. [3–5]
- For cans: vertical vignettes, plan .3 pt reverse traps, avoid critical art in overlap/neck; keep UPC 100% with ≥0.125″ quiet zones. [7]
- Pre‑qualify print choices against APR/CEFLEX/OPRL before artwork lock. [12–14]
12–24 month watch‑outs
- UK EPR eco‑modulation ties fees to recyclability (from 2026–27). [9]
- France MOAH/MOSH ink restrictions (from 2025) impacting global ink ranges/SOPs. [10–11]
2) Definitions & Concepts
- Offset lithography (offset). Planographic plates → blanket → substrate; common for sheetfed paperboard cartons.
- Flexography (flexo). Relief photopolymer plates; anilox‑metered ink; labels, corrugated, films.
- Rotogravure (gravure). Engraved cells in cylinders; superb laydown on massive runs.
- Digital. Electrophotographic (dry/LEP) or inkjet (UV/aq/latex); fast changeovers, VDP.
- Dry offset (cans). Letterset variant; multiple spot colours to blanket → one hit to can; high gain, vignette constraints. [6–7]
- Processing Steps. ISO 19593‑1 layers/metadata for dielines, varnish, braille, etc. [2]
- ISO/IEC 15416 / 15415. Linear / 2D barcode print quality grading methods. [4–5]
Concept map (bulleted)
- Run‑length → Setup cost (plates/cylinders) → Per‑unit cost → Process choice
- Substrate/ink → Compliance (FCM, MOAH/MOSH) & recyclability → Market eligibility [10–12]
- File prep (PDF/X + ISO 19593‑1) → Preflight → Press characterization → Barcode QA (ISO/IEC 15416/15415) [1–5]
3) Standards, Regulations, and Governance
Core technical standards
- PDF/X (ISO 15930: X‑4 / X‑6) for prepress exchange. [1]
- ISO 19593‑1 Processing Steps for dielines/varnish/braille. [2]
- ISO/IEC 15416 / 15415 for barcode print quality. [4–5]
- Can OEM specs (Ball, Crown) are de‑facto standards for dry offset on cans. [6–7]
Regulatory touchpoints
- EU: Reg. (EC) 1935/2004 (FCM), 2023/2006 (GMP), Swiss Ordinance 817.023.21 (inks lists), PPWR adopted. [8,15]
- France: Mineral‑oil‑based ink restriction from 1 Jan 2025 (low MOAH/MOSH). [10–11]
- US: Indirect additive framework; “no‑transfer” principle for inks. [16]
- UK: EPR base fees 2025–26; eco‑modulation from 2026–27. [9]
- Green claims: FTC (US), CMA (UK), EU initiatives. [17–19]
What differs by region
| Topic | US | EU | UK |
|---|---|---|---|
| Food‑contact inks | No ink‑specific federal rule; indirect additive/no‑transfer. [16] | 1935/2004 FCM + 2023/2006 GMP; Swiss lists; France MOAH/MOSH ban. [10,15] | Retained EU FCM regime; UK enforcement. |
| EPR fees | State programs vary. | PPWR adopted; toward harmonization. [8] | Eco‑modulation 2026–27. [9] |
4) Evidence Base & Benchmarks
Representative technical benchmarks
| Item | Typical benchmark (process) | Source |
|---|---|---|
| Can printing screen ruling (max) | ~120 LPI (HD dry‑offset) | [6] |
| Can dot gain | ~20–30% | [6] |
| Can reverse trap | .3–.36 pt between solids | [7] |
| Can min type | Pos 6 pt sans; Rev 7 pt sans | [7] |
| Can UPC | 100% mag; non‑truncated; ≥0.125″ quiet zones | [7] |
| File exchange & barcodes | PDF/X‑4/6; ISO 19593‑1; ISO/IEC 15416/15415 | [1–5] |
Where data are sparse: ΔE tolerances and cost cross‑overs are printer‑specific; use the printer’s target condition and proofs. Evidence gap: consolidated ΔE00 ranges and neutral, current TCO studies.
5) Design & Production Implications
Rules of thumb
- File setup: deliver PDF/X; place dieline/finishing as ISO 19593‑1 Processing Steps. [1–2]
- Barcodes: specify symbology/X‑dim/magnification/bar height/orientation; grade to ISO method on real stock. [4–5]
- Cans: vertical vignettes; avoid fade‑to‑zero across width; plan reverse traps; manage overlap/neck; split solids vs screens as required. [6–7]
- Flexo: higher highlight gain; prefer SCTV‑based spot tone curves; specify anilox BCM/LPI in RFQ. Align locally; cite FIRST/house condition.
- Gravure: superb solids/consistency on films; beware small reverse type in heavy laydown; cylinders add cost/lead time.
- Digital: mind ink/toner limits, heat/UV resistance, food‑contact constraints; qualify for migration/odor if primary pack.
| Process | Strengths | Limitations | Best use cases |
|---|---|---|---|
| Offset | Fine text/tones on paperboard; efficient medium runs | Water balance; limited on non‑absorbent films | Folding cartons, inserts |
| Flexo | Versatile substrates; fast changeover; films/labels king | Highlight stability; plate/ink interactions | PS labels, shrink sleeves, corrugated, flexibles |
| Gravure | Ultra‑consistent laydown; fastest reels | Cylinder cost/lead time; less agile | Massive film runs, metallized looks |
| Digital | No plates; VDP; fast protos/SKUs | Unit cost at scale; adhesion/heat limits | Short‑run SKUs, personalization |
Supplier perspective
Provide target print condition (screen ruling or screening strategy; anilox targets for flexo), spot‑color intent (e.g., coated vs aluminum look on cans), barcode spec, and a finishing map (varnish, foil, emboss) as Processing Steps. [2,7]
6) Sustainability & Compliance Considerations
- Recyclability: Follow APR (US), CEFLEX (EU), OPRL (UK) design rules for inks/labels/adhesives. [12–14]
- Ink/compliance risk: France MOAH/MOSH ban from 2025; verify ink sets/QA plans. [10–11]
- FCM/GMP & Swiss: DoC/GMP for inks on food‑contact packs in EU; US “no‑transfer” principle. [15–16]
- Claims: Use specific, substantiated claims (FTC/CMA/EU green‑claims guidance). [17–19]
7) Workflow & Tooling (ready to adapt)
Checklists
- Print‑ready file: PDF/X‑4 or X‑6; fonts outlined/embedded; images at effective resolution; ISO 19593‑1 layers; overprint intents checked; barcode spec attached; bleed/trims verified. [1–2,4–5]
- Cans: ≤120 LPI; vertical vignettes; reverse traps .3–.36 pt; manage overlap; UPC 100% with ≥0.125″ quiet zones. [6–7]
- Recyclability: Run APR/CEFLEX/OPRL checks pre‑lock. [12–14]
Decision trees
- Choose print process → Run length → Substrate → Required effects → Regulatory (FCM? can?) → Press availability → TCO model.
- Label stock/adhesive → Substrate polymer → Recycling pathway (APR/OPRL) → Print method heat/UV → Life‑environment (ice bucket, pasteurization).
Calculator blueprints
- Breakeven: Flexo unit cost = (platemaking + makeready + press time × rate)/qty + materials; Digital unit cost = (setup + press time × rate)/qty + click/ink + substrate. Solve qty where equal.
- Roll yield (labels): labels per roll = (roll length − waste)/(gap + pitch) × lanes.
- Barcode X‑dimension: derive from magnification & symbology; verify grade on production stock. [4–5]
Template specs (RFQ fields)
- Target process & condition (e.g., flexo anilox BCM/LPI; offset screen; can HD LPI), inks/coatings (low‑MOAH/MOSH where applicable), barcode spec + verification method, recyclability target (APR/CEFLEX/OPRL evidence).
8) Category‑Specific Guidance
Beverage (cans, bottles). Cans: dry‑offset constraints—avoid horizontal fades; split solids vs screens; plan overlap; place UPC around circumference only. Bottles/labels: choose inks/adhesives for wet strength; grade barcodes wet & cold. [6–7]
Food. For primary packs, request ink migration DoCs and GMP evidence; avoid mineral‑oil inks for EU/FR. [10–11,15–16]
Beauty. Metallic looks: compare gravure metallics vs cold‑foil + flexo/offset varnish; check recyclability signals (coverage, label removal) with OPRL/APR. [12,14]
9) Case Studies (Problem → Approach → Result)
1) Beverage can: vignette banding removal
Problem: Horizontal gradient banded and shifted at wrap seam.
Approach: Apply Ball/Crown guidance: vertical vignettes, .3 pt reverse traps, overlap free of critical graphics; HD ≤ 120 LPI. [6–7]
Result: Consistent appearance across batches; UPC grading stable at 100% with required quiet zones.
2) Labels: fast SKU proliferation
Problem: 200 SKUs, 1–3k labels/SKU.
Approach: TCO model favors digital below cross‑over; implement PDF/X‑4 + Processing Steps and APR precheck. [1–2,12]
Measure: Track makeready waste (%), artwork lead time, barcode QA pass rate (ISO grades).
3) Film pouches: gravure vs flexo
Problem: High ink laydown solids with tight registration on 5M+ run.
Approach: Gravure cylinder vs high‑end flexo ECG trials; evaluate ΔE00 stability, unit cost, waste; choose based on local cylinder lead times and price. [8]
10) Common Pitfalls & Red Flags
- Missing Processing Steps (dieline/varnish) → finishing mis‑alignment. [2]
- Barcodes sized/placed without GS1/ISO grading → in‑market scan failures. [4–5]
- Can art ignores dry‑offset constraints (horizontal fades, no reverse traps) → mottling/contamination. [6–7]
- Ignoring recyclability rules until after creative approval → label/ink rework (APR/CEFLEX/OPRL). [12–14]
- Unsubstantiated “green” copy → regulatory risk (FTC/CMA/EU). [17–19]
References
Primary standards & guidance: PDF/X (ISO 15930), ISO 19593‑1 Processing Steps, GS1 General Specifications + ISO/IEC 15416/15415, Ball/Crown can guidelines, PPWR/EPR/MOAH‑MOSH policy notes, APR/CEFLEX/OPRL recyclability, and green‑claims guidance (FTC/CMA/EU). See citations [1]–[19].