Inside CR Resin
The polymer science behind every CRP-Int product — how the resin is made, what it absorbs, and why it works without electricity, fragrance or filters that need replacing every week.
The CR Resin — how it works
A unique polymer formulation developed and continuously refined since 1993. The resin works on the principle of absorption — molecularly binding unwanted gas molecules rather than merely trapping them physically.
Three phases, one molecule
The Molecule
The unique formula — manufactured and processed since 1993 — begins as raw polymer precursors. The molecular structure is engineered to present maximum surface area for gas capture.
Resin Activates
In the second production phase the resin is built up and polymerisation begins. Granules charge up, developing absorbent binding sites for ammonia, formaldehyde and VOCs.
Ready to Absorb
The resin cools to room temperature. The finished granules are highly porous, strongly adsorbent for polar gases, and work excellently even in humid environments.
CR Resin — General data sheet
| Parameter | Specification | Notes |
|---|---|---|
| Subject | Polymer Resin | CR Resin proprietary formula |
| Grain size — fine | 2 – 4 mm | For compact filter cartridges |
| Grain size — coarse | 4 – 10 mm | For aquarium and industrial filters |
| Bulk density | 400 – 450 g / L | Breaking / save weight |
| Operating principle | Absorption | Molecular binding, not physical trapping |
| Ion exchange capacity | High | Superior to activated carbon for polar gases |
| Humidity performance | Excellent | Works well in humid environments |
| Primary target gases | NH₃ & HCHO | ~80% ammonia absorption rate |
| Secondary targets | NO₃⁻ · NO₂⁻ · PO₄³⁻ · VOC | Application-dependent |
| Filter life (consumer) | Up to 30 or 90 days | Typical indoor use at room temperature · 90 days on request |
| Power requirement | 0 W | Completely passive — no electricity |
| Production since | 1993 | EU production · Arendonk, Belgium |
Independent lab data, not a marketing claim
In 2011 NedLab, an independent analytical laboratory in the Netherlands, ran a side-by-side comparison of CR Resin (KatFresh configuration) against high-quality activated carbon. The findings below are taken directly from their report — Analytical Report no. 127617/2011.
CR Resin absorbs ~25× more ammonia than activated carbon
The one-hour test simulates the immediate post-urination period — the moment when ammonia release peaks inside an enclosed litter box. With both filters identical in shape, volume and exposure conditions, CR Resin absorbed the great majority of the ammonia load while activated carbon absorbed only a small fraction of the same load.
Figure 1 — 1-hour ammonia absorption. Reproduced from NedLab Analytical Report 127617/2011.
Performance reports for the other target molecules
A second comparative study, focused on aqueous ion absorption in aquariums, is now also published. Performance data for formaldehyde and VOCs is held internally and available to OEM partners under NDA.
CR Resin — Nitrate, Nitrite & Phosphate Performance Report
Side-by-side aquarium comparison: 25 g CR Resin vs 40 g activated carbon. Resin tank stayed algae-free for 80 days; carbon tank developed algae from day 40. pH stable at 7.5.
Independent lab data, not a marketing claim.
Continuous ammonia load · 0–330 hours
Activated carbon saturates rapidly after ~150 hours; CR Resin declines gradually and remains active.
Source: NedLab Analytical Report no. 127617/2011 · Test article: KatFresh cartridge · Comparator: high-absorptive-quality activated carbon, identical shape and volume.
A second comparative study, focused on aqueous ion absorption in aquariums, is now also published. Performance data for formaldehyde and VOCs is held internally and available to OEM partners under NDA.
25×
The headline number. Side-by-side aquarium comparison: 25 g CR Resin vs 40 g activated carbon. Resin tank stayed algae-free for 80 days; carbon tank developed algae from day 40. pH stable at 7.5.
Formaldehyde
Captured by absorption on the polymer's active sites — molecular binding rather than physical adsorption, with stable performance in humid environments.
Performance data available under NDAVolatile Organic Compounds
Polar and semi-polar organics adhere to the resin's active surface — covering sweat, food, tobacco and general indoor odour compounds without fragrance masking.
Performance data available under NDAFor OEM and procurement use, internal test results and application-specific data are released under NDA. Contact inquiries@crp-int.com with the target application and we'll send the relevant figures.
What CR Resin captures
Safety Data Sheets (SDS)
Safety Data Sheets prepared in accordance with Annex II of Regulation (EC) No. 1907/2006 (REACH), as amended by Commission Regulation (EU) 2015/830. Issue 01/01/2022 · Version 1.01.
CR Resin — Safety Data Sheet (SDS) — Pure Resin for Water and Air Filtration
Single-substance pure polymer filter resin (100% Polymer Filter Resin, neutral state · CAS 26936-95-8).
CR Resin — Safety Data Sheet (SDS) — Polymer Resin + Hydro Corns (30 / 70)
Mixture: 30% Polymer Filter Resin (CAS 26936-95-8) + 70% Hydro Corns (CAS 114808-60-7).
CR Resin — Safety Data Sheet (SDS) — Polymer Resin + Hydro Corns (10 / 90)
Mixture: 10% Polymer Filter Resin (CAS 26936-95-8) + 90% Hydro Corns (CAS 114808-60-7).
All three products are not classified as hazardous under Regulation (EC) 1272/2008 [CLP/GHS]. No hazard statements, no signal word, no precautionary statements required. Documents are made available for OEM, regulatory and procurement use.
Ammonia
What it is
Why it matters
How CR Resin handles it
Common questions about CR Resin
What is CR Resin and how does it remove odour & odor?
CR Resin is a patented polymer filter media engineered in Belgium. It removes odour (UK) and odor (US) through absorption — molecularly binding ammonia, formaldehyde, nitrates, phosphates and volatile organic compounds (VOCs) at the molecular level. Unlike activated carbon, it does not desorb captured molecules when saturated, and unlike sprays it does not mask smells with fragrance.
Does CR Resin absorb ammonia (NH3)?
Yes. Ammonia capture is the most-tested function of CR Resin. Independent lab data shows 96% ammonia removal in one hour versus 4% for activated carbon. It is the filter resin used in 50+ commercial brands including cat-litter cartridges (KatFresh, Catit Magic Blue), hospitality sachets (Sentipure Pro), care-home filters, and veterinary-clinic air-purifier media. Ideal for any environment with an ammonia problem.
Does CR Resin absorb formaldehyde (CH2O)?
Yes. CR Resin chemosorbs formaldehyde — one of the most persistent indoor-air pollutants, found in furniture finishes, MDF, particle board, new-car interiors and many building materials. The polymer binds formaldehyde molecules irreversibly rather than re-releasing them like activated carbon under heat.
Does CR Resin help with aquarium and pond algae problems?
Yes. Algae growth in aquariums and ponds is driven by dissolved nutrients — primarily nitrate (NO3), nitrite (NO2) and phosphate (PO4). CR Resin removes these directly from the water column, starving algae of fuel. This filter resin is used in Fluval Clearmax, JBL Clearmec, JBL Clearmec plus, Zolux Resifilt and many other aquatic filter products worldwide. Independent testing shows stable algae-free conditions over an 80-day cycle.
Does CR Resin remove VOCs and tobacco smell?
Yes. CR Resin captures a broad range of volatile organic compounds (VOCs) including tobacco smell, body-odour fatty acids, kitchen and food odours, sweat compounds, and the lingering VOCs found in shoes, gym kit, locker rooms, hotel rooms after smokers, and used vehicle cabins.
Is CR Resin safe, fragrance-free and eco-friendly?
Yes. CR Resin is fragrance-free, contains no biocides, requires no electricity, and produces no by-products in use. The base polymer is biodegradable and the spent media is non-hazardous. Safety data sheets are available on the products page.
Can I order CR Resin for OEM or private-label products?
Yes. CRP-Int bv supplies CR Resin to 50+ brands across 31 countries as bulk polymer for OEM and private-label finished products: cartridges, sachets, filter inserts, aquarium media, automotive cabin filters. Custom formulations available. Request a sample or quote.