Impact of Different Ink Types on the Durability of Printing Effects on Treated PP Materials

PP (polypropylene) is widely used in packaging and label printing for its good performance and low cost. However, its low surface energy and polarity limit ink adhesion. Pretreatment boosts surface energy, but ink type still greatly affects printing durability.​

Solvent-Based Inks on PP​

Common in traditional printing, they use organic solvents to disperse pigments. On treated PP, solvents evaporate to form an ink film.​

• Indoor: Clear, vivid patterns last 1-2 years (proper ink film thickness).​

• Outdoor: UV, wind, and rain cause fading; mixing auxiliaries (e.g., gold printing adhesives) or thin films shorten durability to months.​

Water-Based Inks on PP​

Eco-friendly (low VOCs) but poor adhesion on PP, even after pretreatment.​

• A food packaging case: Cross-cut test pass rate (72%) is far lower than solvent-based inks (95%).​

• Indoor: Patterns stay recognizable for 6 months-1 year.​

• Outdoor: Blurring/fading occurs in months (weak bonding with PP resists harsh conditions poorly).​

UV-Curable Inks on PP​

UV triggers quick polymerization, forming hard, wear-resistant films.​

• Example: KTF-CO series UV inks on pretreated PP bottles cure fast; 350 mesh/inch prints resist chemicals after 24-hour soaking.​

• Indoor: Durability reaches 3-5+ years.​

• Outdoor: Maintains quality for 1-3 years (tight cross-linked structure resists damage).​

Key Influencing Factors​

1. Ink Composition: Fade-resistant pigments and quality resins extend durability; solvent pores or incomplete water drying reduce it.​

2. PP Pretreatment: Insufficient treatment weakens adhesion; over-treatment damages PP.​

3. Environment/Scenarios: High temp/humidity harms ink films; outdoor UV/rain or chemical contact accelerates aging.​

In practice, choose inks based on product needs, optimize processes, and ensure printing durability to meet market demands.​