1. what an asphalt release agent must actually do
An asphalt release agent has a single, very clear task: to prevent hot bitumen mix from sticking to metallic or coated surfaces. In doing so, the release agent encounters conditions that are rare in the industry:
- Hot mix, typically 140-200 °C
- Mechanical stress, for example through rotating drums or thrust on the screed
- Time pressure, because the mix must be processed within a narrow temperature window
- Changing weather conditions with temperatures ranging from frost to summer heat
- Very different substratesSteel, coated sheet steel, rubber, plastic
This results in four core requirements that every release agent must fulfil:
- Separating effectBitumen must not adhere, or only to a very limited extent
- Service lifeThe release agent must remain on the surface long enough to cover the work step - ideally several spray cycles or rolling passes
- Material compatibilityNo damage to paintwork, rubber, coatings or seals
- SecurityLow fire and health hazards when handling hot material
If you keep these four points together, you quickly realise that the release agent is not a by-product, but a key consumable in asphalt construction - with a direct effect on machine service life, personnel workload and construction site speed.
2. hydrocarbon-based release agents - the traditional concept
2.1 What's inside
Classic hydrocarbon-based asphalt release agents typically consist of aliphatic or slightly aromatic mineral oil fractions, often with additives for durability. They are closely related to the lubricants and fuels that are already in circulation in a construction yard.
2.2 Strengths in practice
- Long technical maturityHydrocarbon products have been around for decades and their behaviour is well documented.
- Very broad material compatibility with the usual steel, paint and rubber parts in asphalt construction.
- Good sprayability even in simple systems, often with low viscosity.
- Robust against frost in storage - most formulations remain liquid well below the freezing point.
2.3 Weaknesses and risks
- CLP labelling obligationMany hydrocarbon-based release agents carry hazard pictograms and H-phrases (e.g. „May be fatal if swallowed and enters airways“, H304).
- ADR (dangerous goods)Depending on flash point and density, transport is subject to the Dangerous Goods Ordinance - with the corresponding requirements for packaging, carrier and accompanying documents.
- VOC emissionsMineral oil-based products evaporate with measurable VOC content, which affects air hygiene and odour pollution.
- Skin stressFrequent or direct contact promotes degreasing and skin irritation, which is a real burden in the daily construction yard routine with seasonal personnel.
- Environmental risk in the event of spillageMineral oil residues on seepage or water surfaces require costly removal.
- Image factorPublic clients and general contractors are increasingly asking for environmentally friendly alternatives.
2.4 When conventional release agents are still useful
- If a supplier standard or product specification explicitly requires a hydrocarbon-based formulation.
- In very special mixed goods constellations in which bio-based products are not effective for purely technical reasons.
- Transitionally during a controlled substitution.
Our product for these cases: Antistick 140 - a proven conventional release agent for users who deliberately do not want to or cannot switch to a bio-based variant.
3. rapeseed oil-based vegetable release agents - the modern concept
3.1 What's inside
Vegetable release agents are based on vegetable oil derivatives - in the case of the Antistick ECO range, consistently on rapeseed oil derivatives from European production. Unlike pure, untreated vegetable oil, these derivatives are processed in such a way that they
- adhere to the substrate for a sufficiently long time,
- do not polymerise or carbonise at the temperatures normally used in asphalt construction,
- atomise evenly in modern spraying systems,
- can be stored for comparatively long periods of time.
3.2 Strengths in practice
- No CLP hazardous substance labellingStorage and handling are significantly relieved, especially with changing personnel.
- No dangerous goods (ADR-free)Transport between building yard and construction site without hazardous goods requirements.
- High flash point (> 150 °C): Much more relaxed when handling hot mix - no risk of ignition from sprayed mist.
- Low VOC to VOC-freeLess odour in the workplace, less pollution in closed halls or garages.
- More skin-friendlyVegetable oil-based products do not degrease the skin to the same extent as mineral oil-based products.
- BiodegradableSpillages can be cleaned up, but do not leave a long-lasting environmental problem.
- Image effectClearly communicable in tenders and sustainability reports („100 % bio-based“, „Release agent based on rapeseed oil“).
3.3 What to look out for
To be honest, plant-based release agents are not automatically better in every respect. They require a few adjustments that every company can make, but should be aware of:
- Frost protection during storageVegetable products become tougher when stored below 0 °C for longer periods. As a rule, warming to room temperature and brief stirring is sufficient - but the storage logistics must take this into account.
- Check spraying systemsVery fine nozzles, which are designed for highly diluted solvent products, can clog with purely plant-based release agents. The low-viscosity variant (e.g. Antistick ECO 150 LV) or a small adjustment to the nozzle selection.
- Check material compatibilityMost painted surfaces, rubber parts and plastic components are compatible. For very sensitive special surfaces, a compatibility test is recommended before the first large-scale introduction - but this applies to every new product.
3.4 Our Antistick ECO family at a glance
| Product | Character | Recommendation |
|---|---|---|
| Antistick ECO 150 | Standard variant based on rapeseed oil | Universal for rollers, planks, troughs, tools |
| Antistick ECO 150 LV | Low viscosity variant (Low Viscosity) | For spraying systems with fine nozzles |
| Antistick ECO 170 | Variant for highly viscous mixtures and long service life | PmB, long transport routes, sophisticated systems |
→ All release agents at a glance
4. direct comparison - the table for the decision
| Criterion | Hydrocarbon release agent | Rapeseed oil release agent (Antistick ECO) |
|---|---|---|
| Raw material base | Mineral oil (fossil) | Rapeseed oil derivatives (renewable) |
| CLP hazardous substance labelling | Frequently required | Generally not required |
| ADR / Dangerous goods transport | Often dangerous goods | Generally not dangerous goods |
| Flash point | Variable, often lower | > 150 °C |
| VOC emissions | Available | Negligible |
| Odour formation | Noticeable | Very low |
| Skin stress | Degreasing | More skin-friendly |
| Behaviour in the event of burial | Persistent, time-consuming cleaning | Biodegradable |
| Effect on bitumen | Very good | Very good |
| Service life on surfaces | Good | Very long with ECO 170 |
| Behaviour in frost (bearing) | Remains fluid | Thickening possible, reversible |
| Image effect Tender | Neutral to critical | Positive |
| Economic efficiency Total costs | Unit price may be lower | TCO often more favourable due to elimination of requirements |
Total costs (total cost of ownership) is actually the decisive factor. What initially looks like „slightly more expensive per litre“ tips in favour of the bio-based variant in many companies as soon as you factor in storage labelling, hazardous goods transport, occupational safety costs, cleaning of spills and possible bonus points in tenders.
5 Which release agent is suitable for which operation?
| Profile | Recommendation |
|---|---|
| Medium-sized asphalt contractor, mixed fleet, normal mixes | Antistick ECO 150 as standard |
| Large-scale operation with automatic spraying systems, fine nozzles | Antistick ECO 150 LV |
| Special operations with PmB / long transport routes | Antistick ECO 170 |
| Construction yard with a high proportion of seasonal staff and a desire for maximum safety | Complete ECO line, no more hazardous materials storage logistics required |
| User with fixed specification for hydrocarbon-based formulation | Antistick 140 |
In a typical substitution project, we recommend the following procedure:
- As-is analysisWhich release agent is used today? Which systems, which mixes?
- Define target productSelect the appropriate Antistick ECO variant based on the system and mix.
- Practical test with test sample: 10 or 20 litres over one or two working days on a real construction site.
- Record characteristic valuesConsumption, spray pattern, adhesion behaviour, cleaning follow-up effort.
- Run-upAfter a successful test, change over successively and use up old stocks.
- Customise logisticsUpdate storage and transport requirements - often entire processes are cancelled.