Water-activated tape, often called gummed tape, has become a popular choice in eco-conscious packaging. Unlike plastic tapes, this paper-based adhesive is activated by water and bonds firmly to cardboard, creating a secure, tamper-evident seal. But how exactly is it made? If you’re curious about the production process—whether you’re in the packaging business or just exploring sustainable materials—this article breaks it down step by step.

What Is Water-Activated Tape?

Water-activated tape (WAT) is a packaging tape made of kraft paper, typically with a starch-based adhesive coating. It stays dry and non-sticky until water is applied, at which point the adhesive activates and forms a strong bond with corrugated surfaces.

Step-by-Step: How Water-Activated Tape Is Made

1. Kraft Paper Backing Production

The process starts with the base: kraft paper. This paper is made by pulping wood fibers—often from responsibly managed forests—and pressing them into durable sheets.

In many cases, fiberglass strands are embedded during this phase to create reinforced WAT (commonly used for heavy packages). For non-reinforced versions, it’s simply one layer of kraft.

📌 Why Kraft Paper?
Kraft paper is strong, recyclable, and biodegradable, making it a sustainable choice for environmentally friendly tape production.

2. Making the Adhesive (Starch-Based)

The adhesive is where things get interesting. It’s usually derived from natural starches like corn, potato, or tapioca. Here’s a simplified overview of the process:

• Stage 1: Mixing
  A blend of starch, water, and a small amount of binding agents (like polyethyleneimine or polyacrylamide) is mixed together.
• Stage 2: Cooking
  This mixture is heated to around 175–210°F (80–99°C) for about 8–30 minutes. This gelatinizes the starch, turning it into a gel with tacky properties when reactivated by water.
• Stage 3: Refinement
  Additional components like wetting agents and viscosity modifiers are added, and the mixture is heated again to ensure consistency and performance.

⚙️ This double-cooking process helps achieve optimal bonding strength while keeping the adhesive shelf-stable until moistened.

3. Coating the Paper

Next, the adhesive is applied to one side of the kraft paper using techniques like:

• Roll coating
• Knife coating
• Blade or rod coating

The coated paper then goes through a drying tunnel to ensure the adhesive sets and stays inactive until water is added during use.

4. Cutting, Rolling, and Packaging

Once dried, the tape is:

• Cut into standard widths (usually 48mm, 72mm, or customized)
• Rolled into compact spools
• Optionally printed with branding using soy-based or algae-based inks
• Packed and shipped

Reinforced vs. Non-Reinforced Tape: What’s the Difference?

Feature	Non-Reinforced WAT	Reinforced WAT
Strength	Light to medium duty	Heavy-duty, up to 40kg packages
Composition	Pure kraft + starch	Kraft + fiberglass + starch
Recyclability	Fully recyclable curbside	Conditionally recyclable
Use Case	E-commerce, light goods	Export shipping, heavy cartons

Environmental Considerations

Water-activated tape has a lighter ecological footprint than its plastic counterparts. Here’s why:

• ✅ Made from renewable paper and starch
• ✅ Biodegradable when non-reinforced
• ✅ Does not require plastic removal during recycling
• ✅ Compatible with circular economy goals

♻️ Even reinforced versions are often considered recyclable when applied to a cardboard box, as the glass fibers account for less than 1% of the package weight.

Why This Process Matters

Understanding how WAT is made helps businesses and eco-conscious buyers appreciate its benefits—not just from a performance standpoint, but from a sustainability perspective as well.

Whether you’re a packaging supplier, brand owner, or startup founder, using WAT is more than a material choice—it’s a statement of values.

Final Thoughts

Water-activated tape is more than just another adhesive. It’s a smart, sustainable packaging solution crafted from paper and plant-based glue, using carefully controlled manufacturing processes.

By switching to WAT, companies can reduce plastic waste, improve package security, and align better with eco-focused consumer expectations.

So, next time you see that simple brown strip sealing a box—know there’s a lot more behind it than meets the eye.

If you’d like help sourcing machinery to produce gummed paper tape in-house, or need custom WAT slitting and printing solutions, we’d be glad to advise. Just get in touch!