What is Water-based Coating Paper?

Water-based coating paper is an innovative, sustainable alternative to traditional plastic-coated packaging.

Unlike conventional polyethylene (PE)-coated paper, which relies on fossil fuel-derived plastics, it uses a water-based dispersion to create a protective barrier.

This dispersion typically contains four core components:

Water (50–75% of the formula): Acts as a solvent, ensuring even application and evaporation during drying.

Binders (e.g., acrylics, starch derivatives, or bio-based latex): Form a film to block moisture, grease, and oxygen.

Fillers (e.g., calcium carbonate, kaolin): Improve coating smoothness, reduce costs, and enhance barrier properties.

Additives (e.g., surfactants, defoamers): Optimize coating stability and performance.

Why It’s Revolutionary:

Plastic-Free: Meets strict regulations like the EU Single-Use Plastics Directive.

Recyclability: The coating dissolves during paper recycling, eliminating the need for complex separation processes.

Food Safety: Complies with FDA 21 CFR and EU 10/2011 standards, ensuring no chemical migration into food.

The Process of Water-based Coating Paper

Producing water-based coating paper involves precision and eco-friendly techniques:

Step 1: Coating Preparation

The water-based dispersion is formulated to meet specific needs (e.g., high grease resistance for pizza boxes).

Binders and fillers are mixed under controlled pH and temperature to prevent clumping.

Step 2: Application Methods

Curtain Coating: A continuous “curtain” of liquid is poured onto paper, ideal for uniform, high-speed production (e.g., 500 meters/minute).

Blade Coating: A metal blade spreads the dispersion evenly; best for thin, smooth layers (common in premium packaging).

Spray Coating: Used for irregular shapes, like molded fiber containers.

Step 3: Drying & Curing

Coated paper passes through infrared or hot-air dryers at 80–120°C. Water evaporates, leaving a dense, hydrophobic layer.

Unlike PE extrusion (which requires 200°C+), WBBC saves 30–40% energy.

Step 4: Quality Testing

Finished paper undergoes tests for:

• Water Resistance (Cobb test: <10 g/m² water absorption).
• Grease Barrier (Kit test: resists oil penetration for 24+ hours).
• Recyclability (pulping tests confirm full fiber recovery).

Case Study: A European paper mill reduced carbon emissions by 25% after switching from PE to water-based coating paper production.

Is Water-based Coating Paper Better than Plastic Coated Paper?

Key Comparisons:

Why it Wins:

Regulatory Compliance: Bans on single-use plastics in 70+ countries favor water-based coating paper adoption.

Brand Reputation: 73% of consumers prefer brands using sustainable packaging (McKinsey, 2023).

Circular Economy: Water-based coating paper can be recycled 5–7 times vs. PE coated paper (often landfilled after one use).

Limitations:

• Cost: Higher raw material prices (e.g., bio-binders cost 20–30% more than PE).

• Durability: Less effective than PE in extreme conditions (e.g., prolonged freezing).

Applications of Water-Based Coating Paper

Water-based coating paper is versatile across industries:

Food & Beverage

• Hot Drink Cups: Withstands 90°C liquids without leakage (e.g., Ecoffee Cup).

• Microwave-Safe Trays: Used for ready meals (tested for 5+ minutes at 800W).

• Frozen Food Packaging: Resists condensation and ice crystal formation.

E-commerce

• Recyclable Mailers: Amazon’s Climate Pledge Friendly program uses WBBC mailers.

• Luxury Packaging: High-gloss WBBC finishes for cosmetics (e.g., Lush’s Naked line).

Healthcare

• Sterile Medical Wrap: Non-reactive with chemicals like ethylene oxide.

• Pharmaceutical Blister Packs: Replaces PVC in eco-conscious markets.

Agriculture

• Seed Packets: Compostable coatings simplify disposal.

Does Water-based Coating Paper Break Down in Nature?

Breakdown Scenarios

Recycling Systems:

• During pulping, water-based coating paper coatings dissolve completely, allowing 95%+ fiber recovery (vs. 60% for PE-coated paper).
• No microplastics are released.

Industrial Composting:

• Certified water-based coating paper (e.g., OK Compost) degrades within 12 weeks at 58°C.
• Binders break into water, CO₂, and biomass.

Home Composting:

• Limited effectiveness due to lower temperatures (20–30°C); partial decomposition may take 6–12 months.

Landfills:

• WBBC degrades anaerobically but slower than composting. No toxic leachate generated.

Certifications to Look For

• ASTM D6400: Ensures industrial compostability.

• Blue Angel: Confirms recyclability and low VOC emissions.

Caution: Avoid mixing non-certified water-based coating paper with organic waste, as synthetic binders may persist.

And here in Kaifeng, our water-based coating paper is mainly used for food packaging —— water-based packaging paper!

Take the KFC burger paper as an example......