Solvent-free — usable in unventilated and enclosed areas
Priming highly absorbent concrete and cementitious screeds
Rayson PrimeBond E25
Rayson PrimeBond E25 is a two-component, medium-viscosity, solvent-free epoxy bonding primer for dry or damp substrates — formulated to wet out and anchor to highly absorbent concrete, screed, asphalt and prepared metal.
Best for
Best for priming porous, highly absorbent concrete and screeds — and asphalt or prepared metal — before Rayson resin floor systems, including in enclosed, unventilated areas.
Real product · Interactive depth view Rayson PrimeBond
Product system Rayson PrimeBond E25
Part A 4 kg / Part B 1 kg per set, or Part A 16 kg / Part B 4 kg per set RY-TDS-102
Rayson PrimeBond E25 has one clearly defined, verifiable job in the coating system.
Rayson PrimeBond E25 is a two-component, medium-viscosity, solvent-free epoxy bonding primer for dry or damp substrates — formulated to wet out and anchor to highly absorbent concrete, screed, asphalt and prepared metal. Best for priming porous, highly absorbent concrete and screeds — and asphalt or prepared metal — before Rayson resin floor systems, including in enclosed, unventilated areas.
Especially suited to highly absorbent substrates
Priming new and existing concrete before Rayson floor systems
Applies to dry or damp surfaces
Priming sound existing epoxy flooring before recoating
Seal porous concrete. Strengthen the bond.
PrimeBond E25 wets out highly absorbent concrete and screed to create a reliable base for the resin floor above.
A controlled route to applying Rayson PrimeBond E25.
This sequence supports early planning. It does not replace the current Technical Data Sheet, approved method statement or project-specific technical review.
- 01
Inspect and prepare the substrate
New and existing concrete (minimum 28 days old, moisture content below 5%)
- 02
Prepare the material as specified
Two pre-weighed parts, mix ratio 4:1 (A:B) by weight; mix mechanically for at least 2–3 minutes; pot life up to 30 minutes at 30 °C
- 03
Apply with the correct tools
Recommended methods: Roller, Brush, Airless spray. Confirm coat count and thickness for the project.
- 04
Protect through the required cure
Final cure 7 days
Coating system cutaway
Every layer has a job—from prepared substrate to service surface.
This diagram explains a typical system position, not a fixed specification. Primer, body coat, finish, thickness and detailing must be confirmed for the project.
Position in the system Primer
Rayson PrimeBond E25 serves as the primer. Confirm the complete build-up against the substrate, exposure and project requirements.
Related system products
Review primers, body layers, finishes or specialist components connected to this product.
- Compatible body coat and finishSelected for the service exposure and complete system
- Rayson PrimeBond E25Primer · Epoxy
- Correctly prepared substrateNew and existing concrete (minimum 28 days old, moisture content below 5%)
Four project facts for faster system screening.
These current product figures support early selection. Confirm the final build-up, quantity and application conditions against the Technical Data Sheet and site conditions.
- Coverage
- Coverage
- Mixing & working time
- Mixing
- Drying & curing
- Curing
- Pack configuration
- Pack
6–8 m² per kg per coat, varying with substrate condition and porosity
Two pre-weighed parts, mix ratio 4:1 (A:B) by weight; mix mechanically for at least 2–3 minutes; pot life up to 30 minutes at 30 °C
Final cure 7 days
Part A 4 kg / Part B 1 kg per set, or Part A 16 kg / Part B 4 kg per set
Confirm the substrate and real service environment before specifying.
Choose it when
- Priming highly absorbent concrete and cementitious screeds
- Priming new and existing concrete before Rayson floor systems
- Priming sound existing epoxy flooring before recoating
- Priming asphalt surfaces before compatible overlays
- Priming mechanically prepared metal
- Priming in enclosed or unventilated areas where solvent primers cannot be used
Relevant applications
Relevant industries
Choose something else when
- Minimum substrate temperature 5 °C; mix and cure between +10 °C and +35 °C
- Substrate moisture content must not exceed 5% — damp is acceptable, standing water is not
- Prepared substrate must reach at least 1.5 N/mm² pull-off strength
- Mixed material must be used within its pot life; cures faster in hot weather and in large batches
- Not a wearing surface — must be overcoated with a Rayson body coat or finish
- Use as a finished wearing surface without an overcoat
- Substrates with standing water or moisture content above 5%
- Slabs with active rising damp or hydrostatic pressure without a specialist barrier system
- UV-exposed surfaces left uncoated — epoxy will yellow and chalk outdoors
Other Rayson products to evaluate
These links continue the comparison; they are not automatic substitutes. Confirm the substrate, exposure and complete build-up before selection.
Substrate requirements+
- New and existing concrete (minimum 28 days old, moisture content below 5%)
- Cementitious screeds, including highly absorbent substrates
- Sound existing epoxy flooring
- Asphalt
- Mechanically prepared metal
Technical documents and project support
Ready to specify Rayson PrimeBond E25? Give Rayson the site conditions.
Send the area, substrate condition, expected traffic or exposure, required finish and programme. The technical team can help review the system build-up and estimated quantity.
What to know before specifying Rayson PrimeBond E25.
What substrates is PrimeBond E25 best suited to?
It is formulated for highly absorbent concrete and cementitious screeds, where its medium viscosity lets it soak in and seal the surface. It also primes new and existing concrete, sound existing epoxy floors, asphalt and mechanically prepared metal.
Can PrimeBond E25 be applied to damp concrete?
Yes — it accepts dry or damp substrates, provided there is no standing water and substrate moisture stays at or below 5%. For wetter slabs or active moisture ingress, speak to our technical team first.
What is the mixing ratio and pot life?
The two pre-weighed parts mix at 4:1 (A:B) by weight, stirred mechanically for 2–3 minutes. Pot life is up to 30 minutes at 30 °C, and mixed material cures faster in hot weather and in larger batches.
How does it differ from PrimeBond E20?
Both are solvent-free epoxy bonding primers usable in unventilated areas, with coverage around 6–8 m² per kg per coat. E25 mixes 4:1 by weight and is aimed at highly absorbent substrates; E20 mixes 2:1.
Is it suitable for enclosed spaces?
Yes — being solvent-free, it is stated as suitable for unventilated areas. Standard PPE and good working practice still apply; consult the SDS once available.
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