EN705 Cured Polyurethane Remover — Solvent-Free Liquid for Machinery, Spray Guns and Moulds

A powerful solvent-free liquid that penetrates and softens hardened, cured polyurethane residue — removing it from spray guns, mixer heads, moulds and machine parts without harsh chemicals or aggressive solvents.

• Removes cured and hardened polyurethane residue — not just uncured or wet PU
• Solvent-free and low hazard — safe to store and use without additional safety precautions
• Penetrates deep into built-up PU deposits on complex parts including spray guns, nozzles and moulds
• Simple soak process — leave for 2 hours minimum, overnight for best results
• Reusable — use the same bath until it stops being effective
• Suitable for all low-pressure polyurethane manufacturing environments

About EN705 Cured Polyurethane Remover

Anyone working with polyurethane knows the problem. Once PU cures and hardens, it becomes extremely tenacious, bonding firmly to the surfaces of spray guns, mixer heads, dispensing nozzles, moulds and any other equipment it contacts. Whether you manufacture foam products, automotive components, sealants, mattresses or building materials, removing cured PU build-up from production equipment remains one of the most time-consuming maintenance challenges in the industry.

EN705 is a liquid cured polyurethane remover, developed specifically to solve this problem. Unlike flushing agents such as EN720, which target wet, uncured PU residue during production runs, EN705 targets hardened, fully cured polyurethane that has already bonded to equipment surfaces. Its formula soaks into the cured PU matrix and breaks the chemical bonds that hold it together, so the residue softens and loses structural integrity until you can wipe or wash it away.

Critically, EN705 achieves this without solvents or harsh chemicals. It carries a very low hazard rating, making it safe to store and use in production environments without the specialist ventilation, PPE or strict handling protocols that solvent-based cleaners demand.

Cured vs Uncured Polyurethane — Choosing the Right Product

Choosing the right cleaner matters, because cured and uncured polyurethane require fundamentally different chemistry to remove.

• Cured / hardened PU residue —polyurethane that has already set and bonded to surfaces. Use EN705. The liquid soak process penetrates and breaks down hardened deposits that mechanical scraping cannot shift.
• Uncured / wet PU residue —polyurethane still in liquid or semi-liquid state, typically present in pipes, mixer heads and processing equipment during or immediately after a production run. Use EN720 Non-Hazardous PU Flushing Agent.

If you are unsure which product you need, contact us and we will advise based on your application.

What Does EN705 Remove?

We’ve formulated EN705 to penetrate and remove:

• Cured and hardened polyurethane (PU) residue
• Built-up PU deposits on complex internal surfaces and blind cavities
• PU residue from low-pressure polyurethane manufacturing equipment
• Cured Epoxy resin and glues

Key Benefits

Penetrates deep into hardened PU deposits

EN705 particularly excels on detachable parts with complex geometries — spray guns, nozzles, static mixers and mould tools — where physical scraping can’t reach into cavities and narrow passages. Because you can fully submerge parts in EN705, the liquid penetrates and works on every surface simultaneously, including areas that would be impossible to clean manually.

Solvent-free and low hazard

EN705 contains no solvents or harsh chemicals. Despite its effective action on cured PU, it has a very low hazard profile, so you can store and use it safely in production environments without additional ventilation requirements, specialist PPE or complex COSHH arrangements. As a result, it’s practical for workshop and factory use at any scale.

Reusable bath — excellent cost-in-use

You don’t need to replace EN705 after each use. Once you’ve cleaned and removed the parts, you can reuse the liquid for subsequent cleaning batches. Only replace the bath once it stops being effective — typically after multiple cycles, depending on the volume and severity of the residue you’re treating.

Returns parts to as-new condition

Used correctly, EN705 softens and releases cured PU build-up completely, returning spray guns, mixer heads, nozzles and mould tools to a clean, operational condition. As a result, you can often restore parts that would otherwise need replacing due to heavy PU build-up, reducing equipment costs.

How to Use EN705 Cured Polyurethane Remover

Standard soak process

Always wear chemical-resistant gloves when handling EN705 and when removing parts from the soak bath.

1. First, place the parts you want to clean in a suitable container — a lidded plastic tub or steel tank sized to let the parts submerge fully.
2. Next, pour EN705 over the parts until fully covered. Always use EN705 neat — do not dilute it.
3. Then, leave to soak for a minimum of 2 hours. For best results, leave overnight (8–12 hours). Very heavy or long-standing PU build-up may benefit from a 24-hour soak.
4. Once softened, remove the parts and wipe or brush away the residue. A stiff brush or wooden scraper works well on any remaining deposits.
5. Afterwards, wash parts in EN730 Inhibited Parts Washer Fluid to remove remaining traces of EN705 and PU residue, and to leave a protective corrosion-inhibiting coating on mild steel parts.
6. Finally, return the EN705 to the container for reuse, and replace the bath once it stops effectively softening PU residue.

Tips for best results

• Always use EN705 neat — diluting will significantly reduce its effectiveness on cured PU.
• For very thick or long-standing PU build-up, extend the soak to 24 hours or repeat the process.
• Keep the container covered between uses to prevent evaporation and contamination.
• Monitor the bath condition over time — darkening and thickening of the liquid indicates it is becoming saturated and approaching end of life.
• Follow up with EN730 Inhibited Parts Washer Fluid to ensure parts are fully clean and protected before storage or reassembly.

Compatible Parts and Equipment

EN705 suits soaking and cleaning detachable machine parts, including:

• Polyurethane spray guns and spray heads
• Mixer heads and static mixers
• Dispensing nozzles and mixing nozzles
• Mould tools and mould cavities
• Pipes, hoses and feed line components
• Valves, fittings and mechanical components
• Any detachable metal part with cured PU build-up

Industries and Applications

Manufacturers use EN705 wherever they process polyurethane and need equipment maintenance, including in:

• Polyurethane foam manufacturing — mattress, furniture and packaging production
• Automotive component manufacturing — PU seals, gaskets and interior parts
• Construction and insulation — spray foam insulation equipment maintenance
• Sealant and adhesive production — PU sealant dispensing equipment
• Reaction injection moulding (RIM) — mould tool and equipment cleaning
• Building products — PU coating and waterproofing application equipment
• General engineering and maintenance — any application where PU has cured onto metal parts

Works Best With

For the best cleaning outcome, use EN705 as part of a two-stage process:

• EN705 — soak to penetrate and soften cured PU residue (step one).
• EN730 Inhibited Parts Washer Fluid — follow-up wash to remove softened residues and any traces of EN705, and to leave a corrosion-inhibiting protective coating on mild steel parts (step two).

If your application involves uncured or wet polyurethane residue in processing equipment during production, EN720 Non-Hazardous PU Flushing Agent is the appropriate product for that stage of cleaning.

Product Specifications

• Type: Liquid cured polyurethane residue remover
• Target residue: Cured / hardened polyurethane (PU)
• Solvent content: Solvent-free
• Hazard classification: Low hazard
• Application method: Soak bath (neat, do not dilute)
• Soak time: Minimum 2 hours; overnight recommended; 24 hours for heavy build-up
• Reusable: Yes — replace when no longer effective
• Suitable for: Spray guns, mixer heads, nozzles, moulds, metal machine parts
• Recommended follow-up: EN730 Inhibited Parts Washer Fluid