SC7000 Flexographic Water-Based Ink for Plastic Woven Bags

Plastic woven bags are widely used for chemicals, building materials, grains, and other bulk commodities. Their printed surfaces must withstand harsh conditions such as sun exposure, rain, friction during handling, and compression from stacking, while meeting environmental compliance requirements.

StarColor's SC7000 series flexographic water-based ink, specially developed for woven bags, provides high adhesion, abrasion resistance, anti-aging, and low VOC emissions. It has been successfully applied in multiple leading domestic woven bag manufacturers, offering a durable and compliant printing solution for bulk packaging.

Industry Challenges: Durability and Compliance

• Poor adhesion and abrasion resistance: Traditional solvent-based inks fail to adhere well to rough woven surfaces (PP/PE), with cross-cut adhesion tests at 1B-2B. During handling, printed layers peel off easily, causing more than 30% unclear markings and increasing logistics errors.
• Weak weather resistance: Outdoor exposure causes fading, bleeding, and chalking with conventional inks, preventing long-term label clarity.
• High environmental compliance costs: Solvent-based inks emit 250-300g/L VOCs. Enterprises must invest heavily in RTO or activated carbon treatment equipment, costing over 1.5 million RMB, with annual operation costs of 300,000-400,000 RMB, creating compliance risks for SMEs.

StarColor Solution

StarColor has optimized the ink formulation and printing process for woven bags, launching SC7000 series flexographic water-based ink to precisely address industry pain points.

1. Ink Formulation: Durability & Environmental Compliance

• High adhesion and abrasion resistance: Acrylate-chlorinated vinyl resin composite penetrates fibers forming “anchoring” bonding, with 2% adhesion promoter, achieving 4B-5B adhesion. Adding 5% micro polyethylene wax reduces friction coefficient to 0.3, allowing over 800 rubs under 500g load; post-handling mark clarity remains above 95%.
• Enhanced weather resistance: UV absorbers and antioxidants improve UV aging by 60%; 60-day outdoor exposure shows ΔE ≤ 2.5, no fading or chalking. Hydrophobic monomers prevent bleeding and peeling after 24-hour water immersion.
• Low VOC & environmental compliance: Mainly water-based with small environmentally friendly co-solvents; VOC ≤ 40g/L, meeting GB 38507-2020 standard. Only a simple activated carbon filter is needed, reducing annual environmental costs by 80%.

2. Process Adaptation: Compatible with Existing Equipment

• Substrate pretreatment: PP/PE woven fabrics treated with low-temperature plasma (300W), surface tension 38-42 dyn/cm, ensuring ink wettability. Extremely rough surfaces may receive 0.5μm water-based primer for enhanced adhesion.
• Printing parameters: 60-80 mesh anilox rolls (12-15 BCM), ink layer 15-20μm, doctor blade 65 Shore A, printing pressure 2.0-2.2bar.
• Drying optimization: Hot air + infrared combination, 55-60°C hot air, 3-4 m/s wind, IR preheat 60-65°C, total drying 3-4 seconds at 200 m/min, preventing wet film sticking.

Case Study: Production Upgrade at a Woven Bag Manufacturer

Shandong Plastic Woven Bag Factory, producing over 200 million bags annually, serves fertilizers, building materials, and grain sectors. Previously, solvent-based ink led to peeling complaints and high environmental costs. After switching to SC7000 series ink:

• Durability: Adhesion 5B, abrasion over 800 rubs. Mark clarity post-handling increased from 70% to 98%. Outdoor exposure 60 days, ΔE=2.3, fading/chalking eliminated, customer returns dropped from 8% to 1.2%.
• Environmental compliance: Workshop VOCs reduced from 180mg/m³ to 50mg/m³, only simple activated carbon filter needed, annual environmental cost dropped from 350,000 RMB to 70,000 RMB (80% savings).
• Cost efficiency: Ink utilization increased from 80% to 92%, annual consumption dropped from 120t to 100t, raw material cost saved 240,000 RMB; drying time reduced 30%, line speed from 180 m/min to 220 m/min, daily output increased by 120,000 bags.

Conclusion: The Comprehensive Solution for Woven Bag Printing

StarColor SC7000 series flexographic water-based ink addresses traditional ink limitations, improves abrasion and weather resistance, and reduces environmental costs through low VOC formulation. Currently, SC7000 serves over 20 woven bag manufacturers, covering fertilizers, building materials, grains, and chemicals. Choosing StarColor ensures durable, compliant, and high-quality printing for plastic woven bags.