Traditional textile dyeing consumes between 70–150 L of water per kilogram of fabric, contributing to an estimated 5.8 trillion litres of water use annually in the global fashion sector. Wastewater from dyeing often contains 10–20% unfixed dyes, salts, dispersants, and heavy metals, creating measurable ecological risk across major textile hubs.

Waterless dyeing technologies—supercritical CO₂ dyeing, Air Dye, and solution-dyeing—offer quantifiable reductions in resource use and demonstrably lower chemical emissions. This guide provides a high-evidence, implementation-ready overview for swimwear brands and manufacturers aiming to transition to scientifically validated, standards-compatible waterless dyeing workflows.

Key Insights

• Waterless dyeing technologies reduce water use by 90–100%, depending on method.

• Supercritical CO₂ dyeing (SC-CO₂) delivers high colour fastness (ISO 105-C06) and excellent reproducibility for synthetic swimwear fabrics such as polyester and polyamide (nylon).

• Air Dye and similar gas-phase processes can reduce energy use by up to 85% and water use by up to 95% compared with conventional methods.

• Using recycled materials such as eco-friendly swimwear fabrics, ECONYL® and REPREVE® supports circularity and is compatible with most waterless dyeing workflows.

• Structured tracking of water, energy, chemical use, and waste per kilogram of fabric is essential for audit-ready sustainability reporting and for communicating impact to customers.

• Communicating verifiable data and recognised certifications builds trust and supports premium positioning in the sustainable swimwear segment.

1. Why Waterless Dyeing Matters

1.1 Environmental Significance

Conventional aqueous dyeing relies on up to 8,000 chemical substances , many of which require effluent processing to meet wastewater discharge regulations (e.g. ZDHC MRSL, EU REACH).

Documented impacts include:

• Heavy-metal and azo-dye contamination in surface and groundwater.

• High COD/BOD loads in rivers near textile production zones.

• Elevated risks of dermatitis and respiratory issues for workers exposed to chemical mists and heated wet processes.

The Citarum River in Indonesia is a widely cited example of cumulative pollution from poorly treated textile wastewater. By contrast, waterless dyeing routes significantly reduce both effluent volume and chemical load.

Solution dyeing , where pigment is added directly into the polymer melt, has shown:

• Up to 79% less water use.

• Approximately 20% lower electricity consumption.

• Up to 25% fewer CO₂ emissions over the fabric’s life cycle.

1.2 Industry & Consumer Drivers

The swimwear industry is rapidly shifting towards sustainable swimwear . Brands increasingly favour recycled fibres such as ECONYL® and REPREVE®, often produced from post-consumer plastic bottles and discarded fishing nets.

At the same time, consumers are demanding:

• Verified environmental claims rather than generic “eco” labels.

• Transparency on material origin and dyeing methods.

• Responsibly managed supply chains with fair working conditions.

Tip: By choosing eco-friendly swimwear produced with waterless dyeing, brands can reduce impact while retaining performance and colour brilliance.

2. Waterless Dyeing Technologies

2.1 Supercritical CO₂ Dyeing (SC-CO₂)

Technical Overview

Supercritical CO₂ dyeing uses carbon dioxide in a supercritical state as the dyeing medium instead of water.

• Critical point of CO₂: 31.1°C and 73.8 bar.

• Operating pressure: typically 80–250 bar.

• Temperature range: generally 100–140°C.

• Dye type: disperse dyes with appropriate CO₂ solubility.

In this state, CO₂ has liquid-like solvency and gas-like diffusivity, allowing it to dissolve disperse dyes and transport them deeply into the fibre structure. The CO₂ is then depressurised, recovered, and reused, achieving recycling rates of up to 95%.

Suitability for Swimwear

Supercritical CO₂ dyeing works best with synthetic substrates such as:

• Polyester (PET) fabrics commonly used in performance swimwear.

• Polyamide (nylon) including PA6 and PA66 blends.

Key benefits for swimwear manufacturers include:

• High, consistent colour depth and levelling.

• Excellent colour fastness (washing, light, and rubbing) after repeated exposure to chlorinated and salt water.

• Elimination of dye-bath wastewater and reduced need for chemical auxiliaries.

2.2 Air Dye & Alternative Solvent-Free Methods

How Air Dye Works

There are other waterless approaches besides CO₂. Air Dye technology uses heat and air to turn dyes into a gas, transferring them onto the fabric surface. Some variants use compressed air to spray dye in precise patterns, enabling both solid colour and printed effects.

Typical advantages:

• Up to 95% less water than conventional dyeing.

• Significant reductions in energy use (often 50–85%).

• Compatibility with multiple fibre types after appropriate testing.

• Reduced or eliminated post-dyeing washing, further cutting water and energy consumption.

2.3 Technology Comparison

Note: Both methods enable waterless dyeing of high-performance swimwear while dramatically reducing environmental impact.

3. Choosing Eco-Friendly Materials

Image Source: pexels

3.1 Fibre Compatibility

Selecting the right base fabric is essential for both performance and process stability. Modern digital and waterless dyeing systems can work across a wide range of fibre types, which simplifies swimwear fabric selection .

Commonly used fabrics for waterless dyeing include:

• Cotton and viscose (subject to additional testing and pre-treatment).

• Nylon (polyamide) and polyester blends used in performance swimwear.

“Presto Max has helped us move forward quickly. One machine can print cotton, viscose, nylon, or polyester with the same formula. It’s brilliant.”

3.2 Sourcing Sustainable Options

To align material choices with sustainability objectives, consider deadstock, recycled, organic, and certified options. You can find an overview of such fabrics in resources like sustainable swimwear material guides .

By asking your suppliers for verified recycled and certified options, you reduce environmental impact and signal a clear commitment to responsible sourcing.

3.3 Preparing Materials

Before applying any waterless dyeing process, fabrics should be:

• Cleaned and inspected for defects.

• Pre-treated with low-impact scouring where necessary.

• Tested via small laboratory samples (lab dips) to confirm colour behaviour.

Tip: A tidy, well-documented workspace protects materials and makes each step of your process more efficient and repeatable.

4. Implementing Waterless Dyeing in Production

4.1 Adoption Steps

Assessing Capabilities

Start by evaluating your existing production capabilities:

• Machine readiness (pressure ratings, temperature control, safety systems).

• Available space for new equipment, including ventilation and safety zones.

• Current fabric portfolio and compatibility with waterless techniques.

• Team expertise in digital printing, dyeing, or advanced textiles.

Selecting Technology Partners

Look for partners with proven experience in waterless and low-impact textile technologies, ideally with a track record in swimwear fabrics. Strong partners typically offer:

• Process design and configuration support.

• Operator training and troubleshooting guides.

• Maintenance contracts and spare parts planning.

Training Staff

Staff should be trained on:

• Operation and safety of high-pressure or gas-phase equipment.

• Dye handling, storage, and preparation protocols.

• Preventive maintenance and basic troubleshooting.

Tip: Ongoing training reduces error rates and improves both quality and safety as new technologies are adopted.

4.2 Workflow Integration

Map out your entire production flow and integrate waterless dyeing at the most logical stage. Ensure that material movement between cutting, dyeing, printing, and finishing is clearly defined and documented.

4.3 Quality Control

Set up systematic checks at each stage of production. Recommended tests include:

• Colour fastness to washing (ISO 105-C06).

• Colour fastness to light (ISO 105-B02).

• Colour fastness to rubbing (ISO 105-X12).

For swimwear, it is also important to evaluate performance after exposure to chlorinated pool water and salt water, following swim-specific protocols where available.

Note: Reliable quality control builds consumer trust and strengthens brand positioning in the sustainable performance segment.

Potential challenges when adopting waterless dyeing include:

• High initial capital expenditure: systems can cost $2.5 million to $4 million .

• Limited familiarity among staff and local suppliers.

• Fibre compatibility constraints for some processes.

• Logistics of moving pre- or post-treated fabrics between sites.

5. Overcoming Challenges

5.1 Cost and Investment

Major investments in new technology should be evaluated through a medium- to long-term lens, considering:

• Water and energy savings at the plant level.

• Reduced effluent treatment and chemical procurement costs.

• Potential price premiums for certified sustainable swimwear.

Tip: Explore green financing, equipment leasing, or cost-sharing models with partner brands to make initial investment more manageable.

5.2 Technical Barriers

Technical challenges can often be resolved by:

5.3 Colour Fastness

For waterless dyeing, colour fastness is typically equal or superior to conventional dyeing when the process is optimised. Always:

• Test samples under real-use conditions.

• Confirm supplier data with in-house or independent lab tests.

• Select dyes and auxiliaries engineered for your specific fibre blend.

Note: Request test reports from your dye and chemical suppliers to support your marketing and certification documentation.

5.4 Certification Issues

Certification helps validate your claims and simplifies communication with consumers, retailers, and regulators. Many shoppers actively look for recognised eco-labels on product hangtags and online listings.

Tip: Ask fabric and yarn suppliers if they already hold GOTS, Oeko-Tex, Bluesign®, or GRS certifications—this can save time and simplify your own certification process.

6. Maximising Impact and Growth

6.1 Measuring Sustainability

You can’t improve what you don’t measure. Start tracking core metrics monthly and per kilogram of fabric:

Tip: Share key numbers on your website or in annual sustainability reports—transparent data builds trust with both consumers and B2B partners.

6.2 Communicating Eco-Friendly Benefits

To communicate the benefits of your eco-friendly swimwear , use clear and verifiable messages:

• “This product uses waterless dyeing, saving up to 95% of water compared to conventional processes.”

• “Produced with GRS-certified recycled polyester yarns.”

• “Dyed without traditional dye baths, eliminating dye effluent from this step.”

Note: Honest, specific claims perform better than vague statements like “eco” or “green” and reduce greenwashing risk.

6.3 Scaling Up

To scale waterless dyeing safely:

• Begin with pilot runs and small-batch orders for key customers.

• Standardise parameters and documentation once results are stable.

• Gradually expand capacity while recruiting and training additional operators.

• Use digital tools to track KPIs and maintain consistent quality at higher volumes.

Tip: Scaling gradually helps maintain quality and ensures that sustainability goals stay aligned with business growth.

7. The Future of Greener Swimwear

7.1 Innovations Ahead

You can expect rapid innovation along three main fronts:

• Bio-based dyes and auxiliaries compatible with waterless and low-liquor processes.

• Advanced recycled polymers with improved mechanical performance and colour uptake.

• AI-assisted colour management and process optimisation for further resource savings.

Tip: By testing new technologies early, you position your brand as a leader in cutting-edge swimwear fabric innovations .

7.2 Competitive Advantage

Brands that combine recycled materials and waterless dyeing methods gain a clear edge:

Note: Clear, data-backed sustainability stories help your swimwear stand out in a crowded market.

7.3 Industry Collaboration

Collaboration accelerates adoption of greener swimwear. Consider:

• Joining working groups focused on recycled materials and waterless dyeing.

• Participating in beach-cleanup or bottle-collection programmes that feed into recycled fibre supply chains.

• Sharing best practices and technical learnings through forums and trade events.

Callout: By working with other brands and suppliers, you can scale the impact of recycled materials and waterless dyeing far beyond your own operations.

To summarise, you can lead the transition to greener swimwear by:

1. Selecting high-performance, eco-friendly fabrics.

2. Choosing the most suitable waterless dyeing technology for your needs.

3. Training your team on new methods and safety procedures.

4. Measuring and communicating your environmental performance with real data.

Tip: For further guidance, consult resources from organisations such as Textile Exchange and join industry forums dedicated to sustainable swimwear.

FAQ

What is waterless dyeing?

Waterless dyeing refers to dyeing methods that use little to no water to colour fabrics. Technologies such as supercritical CO₂ and Air Dye replace traditional water-based dye baths, drastically reducing wastewater and chemical discharge.

Can you use waterless dyeing on all swimwear fabrics?

Waterless dyeing works very well on synthetic fibres commonly used in swimwear, including polyester and nylon. Natural fibres such as cotton or bamboo can sometimes be used, but they require additional testing and specific process tuning.

Does waterless dyeing affect swimwear quality?

When optimised, waterless dyeing can improve colour fastness and appearance while maintaining fabric handfeel and mechanical properties. Many brands report brighter colours and better batch-to-batch consistency compared to conventional methods.

How much water can you save with waterless dyeing?

Depending on the technology, you can typically save between 90–100% of the water used in the dyeing stage, significantly lowering your overall water footprint.

Is waterless dyeing safe for workers?

Yes. Waterless systems reduce exposure to hot dye baths and many hazardous auxiliaries. However, they introduce other safety considerations (e.g. high pressure for SC-CO₂), so proper training and safety systems are essential.

How do you tell customers about your eco-friendly swimwear?

Use product tags, website content, and social media posts to share verifiable data about your process. Highlight water and energy savings, recycled material content, and relevant certifications using simple icons and clear language.

What certifications should you look for?

You can request these certificates from your suppliers and showcase them on your product pages, hangtags, and brand communications.