Overview
ISO 12642-2:2006 - Graphic technology - Input data for characterization of 4‑colour process printing - Part 2: Expanded data set - defines a standardized set of ink value combinations for characterizing four‑colour (CMYK) process printing. The expanded data set (1 617 ink value combinations) is intended as a robust, process‑neutral basis for color characterization across a wide range of printing methods (offset, gravure, flexography, metal‑decorating, etc.). It can also be used with any three chromatic inks plus a dark ink. ISO 12642-2 is an alternate to ISO 12642-1 where denser sampling is required.
Key topics and technical requirements
- Data set definition: A comprehensive collection of CMYK ink value sets covering tone scales, neutral/near‑neutral combinations, multi‑colour overprints and highlight/shadow detail suitable for general and packaging printing.
- Size and composition: The full expanded set totals 1 617 combinations, incorporating the 1 485 elements of the ECI 2002 dataset and the essential elements of ISO 12642‑1, with controlled duplication to preserve visual symmetry.
- Flexibility of layout: ISO 12642‑2 specifies ink value combinations only - users may arrange patches in any layout. When exchanging targets, a mapping table (row/column ↔ ID) must be provided.
- Default layouts: Two recommended layouts are provided (Annex A): a logical “visual” layout and a randomized layout to minimize localized ink interactions. Reference CSV files (e.g., 12642‑2_default.csv, 12642‑2_summary.csv) document ID ↔ CMYK mappings.
- Flesh‑tone supplement: Annex B includes a 112‑element flesh tone data set for additional skin‑tone sampling (not part of the core 1 617 set).
- Data identification: Recommended exchange identifiers - ISO12642-2, ECI2002, ISO12642-1, ISO12642-2AnnexB.
- Intellectual property note: The document flags a claimed patent (Konica Minolta) associated with aspects of the data; ISO records licensing willingness by the patent holder.
Applications and who uses it
ISO 12642-2 is used wherever accurate color characterization and profiling of printing processes are needed:
- Color management engineers developing ICC profiles and device characterizations
- Prepress and production teams setting up presses and verifying tone reproduction
- Packaging and commercial printers needing denser highlight/shadow sampling
- Software and instrument vendors creating targets, measurement workflows, or QA tools
- Research labs and standards bodies comparing process performance across substrates and technologies
Practical benefits include improved profiling accuracy, consistent exchange of characterization data, and a common baseline for cross‑process quality control.
Related standards
- ISO 12642‑1:1996 - Initial data set for 4‑colour process printing
- ECI 2002 / DIN 16614:2004 - A related expanded dataset (1 485 elements) incorporated into ISO 12642‑2
Keywords: ISO 12642-2, CMYK, four‑colour process printing, color characterization, print profiling, ECI 2002, ISO 12642-1, ink value sets, printing standards, packaging print quality.
