Pushing the Boundaries of Creative Print on Interactive Billboard
At Project Print Management, we are no strangers to complex, unconventional, and technically demanding print projects. When Greenpeace approached us once again with another ambitious concept for their ongoing Detox campaign, we knew this would be a challenge that demanded innovation, precision, and a deep understanding of environmentally responsible print production.
This time, the brief was not just about scale or sustainability—it was about interaction. Greenpeace wanted to engage the public in a way that was visual, memorable, and thought-provoking. The result was a truly unique interactive billboard and poster campaign that invited people to quite literally wash and learn.
The Greenpeace Poster and Billboard Challenge
At the beginning of the year, Greenpeace asked us to develop an eco-friendly, paper-based poster and billboard system that could deliver two messages in one design, activated through public interaction.
The campaign consisted of:
Posters measuring 1200mm x 1800mm
Large-format paper billboards measuring 2500mm x 3500mm
These installations needed to be visually striking, environmentally responsible, and robust enough to be distributed internationally—while still encouraging people to engage with them directly.
Two Messages, One interactive Billboard Experience
The core concept behind the interactive billboard was simple in theory but complex in execution.
Message One: The Teaser
At first glance, the public would see a stark message:
“Want to know a dirty little secret?”
The rest of the poster or billboard was completely blacked out, creating intrigue and encouraging curiosity. This minimalist approach was designed to stop people in their tracks and prompt them to interact.
Message Two: The Reveal
Once water was applied—either by hand, sponge, or even rain—the blackout layer would wash away to reveal the second, more powerful message beneath:
“Global fashion brands are poisoning our rivers.”
Accompanying the text was a striking illustration of a pipe spilling toxic waste into a river, alongside the Greenpeace website address and a QR code for further engagement.
This transformation was the heart of the campaign, turning a static print into a living, interactive communication tool.
Designing an Interactive Billboard That’s Eco-Friendly
From the outset, Greenpeace were clear that environmental responsibility was non-negotiable. Every material and process used had to align with their sustainability principles.
Eco-Friendly Paper Selection
The posters and billboards were printed on 200gsm paper manufactured using an ECF (Elemental Chlorine Free) bleaching process. This paper was chosen not only for its print quality but also for its strong environmental credentials.
The paper manufacturer operates under:
A stringent carbon emission reduction programme
Renewable energy initiatives, including biomass and enzymatic treatments
ISO 9001 Quality Management Certification
ISO 14001 Environmental Management Certification
This ensured the foundation of the interactive billboard campaign was responsibly sourced and produced.
The Clever Bit: Water-Soluble Ink Technology for interactive Billboard
What truly set this project apart was the use of a special water-soluble ink.
This ink was:
Biodegradable
Practically non-toxic to aquatic species
Non-bioaccumulative
In other words, the ink could safely wash away without harming the environment—perfectly reinforcing the campaign’s message about water pollution.
The water-soluble layer allowed the public to physically interact with the posters, revealing hidden information while reinforcing Greenpeace’s call for cleaner rivers.
Combining Digital and Traditional Print Techniques
Producing an interactive billboard like this required a hybrid approach, combining modern digital printing with traditional screen-printing techniques.
Step 1: Primary Image Printing
The main imagery—the pollution illustration, QR code, and background content—was digitally printed on a UV printer. This ensured:
High colour accuracy
Sharp detail at large scale
Excellent consistency across all prints
Step 2: Blackout Layer Application
The blackout area was then applied using a traditional screen-print process, laying down the special water-removable ink over the underlying message.
This step was critical. The blackout had to:
Fully obscure the second message
Wash away evenly when water was applied
Maintain stability during transport and installation
Multilingual and Multi-Country Complexity
As if the technical challenges weren’t enough, the campaign also had to be produced in seven different languages and distributed to ten countries around the world.
The countries involved included:
Mexico
Spain
Thailand
Indonesia
East Asia
Germany
Switzerland
Philippines
Sweden
Denmark
Each language version required meticulous attention to layout, alignment, and consistency to ensure the message retained its impact regardless of location.
Adding the “Dirty Little Secret” Slogan on the interactive Billboard
The teaser slogan—“Want to know a dirty little secret?”—was also translated into seven languages and produced separately.
This text was:
Digitally printed on a HP 9000 high-resolution printer
Printed onto self-adhesive vinyl
Hand-applied to each individual poster and billboard
Hand application ensured perfect placement and avoided damaging the water-soluble blackout layer.
Packaging, Logistics, and Global Distribution
Once complete, the interactive billboard posters were carefully rolled into protective tubes and air-freighted to all ten countries.
As with many international campaigns, logistics presented their own challenges. While most shipments arrived on time, customs delays affected some deliveries—one package took nearly three weeks to reach its destination.
Despite these setbacks, the majority of Greenpeace’s global branches received their materials and successfully launched the campaign.
Public Interaction and Real-World Impact
One of the most rewarding aspects of this project was seeing how the public responded.
Greenpeace teams across the world documented people interacting with the posters—washing away the blackout layer, discovering the hidden message, and engaging with the campaign in a tactile, memorable way.
This level of interaction is what makes an interactive billboard so powerful. It transforms passive viewing into active participation, making the message far more likely to resonate and be remembered.
Print That Reinforces the Message
What made this project especially effective was how the medium reinforced the message.
Water revealed the truth about water pollution
Eco-friendly materials supported environmental credibility
Interaction encouraged learning and curiosity
Rather than simply telling people about pollution, the posters allowed them to experience the revelation for themselves.
This Greenpeace project is another strong example of the kind of innovative, challenging print solutions Project Print Management specialises in.
From concept development and material sourcing to complex production workflows and international distribution, this campaign required careful coordination at every stage.
Why interactive Billboard Matter
In an age of digital overload, physical interaction can be incredibly powerful. An interactive billboard:
Stops people in their tracks
Encourages curiosity and engagement
Creates memorable experiences
Works across cultures and languages
For campaigns that need to cut through the noise, interactive print remains a highly effective tool.
If you’d like to see more examples of our work with Greenpeace, including large-scale eco campaigns, please visit our World Record Eco Banner project.
Looking for Unusual or Challenging Print Projects?
If you’re planning a campaign that pushes creative or technical boundaries, we’d love to hear from you. Project Print Management specialises in turning complex ideas into real-world print solutions—no matter how challenging.
Contact us to discuss how we can help bring your next campaign to life.
For more information on other Greenpeace work we have produced please visit World Record Eco Banner.
Information from Greenpeace web site:
Dirty little secret For World Water Day we decided to tell you a little secret, just wash and learn.
