—What are the processes of digital printing in the field of flexible packaging? What are the application areas of digital printing?
1. Essential definition of digital printing
Digital printing is a printing technology that directly converts electronic files (PDF/AI, etc.) into printed products without physical printing plates. Its core is to dynamically generate images and texts on the substrate through a computer-controlled imaging system (inkjet/static/laser).
Key features:
✅ No platemaking process | ✅ Variable data printing (different content for each sheet) | ✅ On-demand production (one sheet starts printing)
✅ Fast order change | ✅ Digital color management
Essential difference from traditional printing:
Traditional printing (gravure/offset printing) relies on fixed printing plates to transfer ink, while digital printing is a direct channel from “digital file → imaging device → substrate”.
2. Four core processes of digital printing of flexible packaging
Due to the particularity of materials (PE/BOPP/PET/aluminum foil, etc.) and post-processing requirements (compounding/bag making), flexible packaging has strict standards for printing processes:
1. Electronic ink printing
(such as HP Indigo) Charged ink particles are positioned by electrodes and transferred to the rubber blanket for heating and curing. PET/OPP/PE/aluminum-coated films have colors comparable to offset printing, strong adhesion, high equipment cost, and medium speed.
2. UV inkjet printing
(such as Durst/Konica) Piezoelectric nozzles spray UV ink, UV-cured PE/PP films with high speed (150m/min+), scratch resistance requires pre-coating, and composite adaptability needs to be optimized.
3. Water-based inkjet printing
(such as KM1024i) Water-based ink is sprayed through nozzles, hot air drying penetrates paper-based composite materials, some films are the most environmentally friendly (VOC tends to zero) Slow drying, high water resistance requirements
4. Solvent inkjet printing
(such as EPSON) Solvent-based ink jet printing, volatile drying film formation Untreated PE/PP material compatibility is wide High VOC emissions, need post-processing
Core challenges of flexible packaging:
Ink adhesion on non-polar films (such as PE)
Post-printing composite strength (especially UV ink)
Content resistance (grease/acid and alkali) test
III. Core application areas of digital printing
Flexible packaging
Small batch customized bags (pet food/coffee)
Regional promotional packaging (different languages/QR codes)
New drug aluminum foil blister printing (HP Indigo is FDA certified)
Label printing
Anti-counterfeiting traceability label (variable QR code + invisible watermark)
Electronic label (printed RFID antenna)
Commercial printing
Personalized publications (printing on demand)
Variable data direct mail advertising
Industrial printing
Building material decorative film (wood grain/stone grain)
Flexible electronic circuit printing
IV. Digital printing VS traditional printing cost critical point
When the order length is less than 3,000 meters, the comprehensive cost of digital printing is lower (eliminating the waste of plate making/testing materials/warehousing).
Post time: Jul-18-2025