Censil651 is built to replace SYLOID® ED 2 in waterborne systems where fine touch and a smooth appearance on thin films decide the job.
Quick answer
Censil651 runs at d50 4.9 – 5.2 μm against Grace's published 4.5 μm for SYLOID® ED 2 — slightly coarser, in the same fine-touch band. The bigger difference is deliberate: Grace lists ED 2 as untreated, while Censil651 is wax-modified. That wax layer is what controls anti-settling and surface touch in a waterborne system, where an untreated silica is more prone to hard sediment.
Each column reproduces figures from the publishing manufacturer’s own documentation, cited below the table.
| Parameter | SYLOID® ED 2by W. R. Grace & Co. | Censil651Fine touch & smooth appearance |
|---|---|---|
| Median particle size, d50 | 4.5 μm (average, light scattering) | 4.9 – 5.2 μm |
| Pore volume | Not stated in cited source | 1.6 – 1.8 mL/g |
| Specific surface area | Not stated in cited source | 250 – 280 m²/g |
| Surface treatment | None (untreated) | Wax-modified (organic / PE-wax; grade-dependent) |
| pH | 7.0 | 6.0 – 8.0 (5% susp.) |
| Oil absorption | 320 g/100g | Not stated in cited source |
| SiO2 content, dry | Not stated in cited source | ≥ 99% |
| Recommended dosage | Not stated in cited source | 1 – 4% |
| Packaging | 10 kg bag | 20 kg multi-wall bag, palletized |
SYLOID® ED 2 column — W. R. Grace & Co. — SYLOID® Matting Agents for Coatings and Printing Inks, Technical Information, Product Properties EMEA Region, DOC062 (© 2021). Censil columns — Censilcoat published grade specification, products page. “Not stated in cited source” means the value does not appear in the document cited; no figure has been estimated, inferred, or transferred between columns.
Separate from the datasheet comparison above: our laboratory in Fujian ran a commercially purchased sample of SYLOID® ED 2 and Censil651 side by side in the same waterborne acrylic system over 2025 Q4 – 2026 Q1. Every figure below is our own parallel measurement — not a manufacturer specification. Star ratings are relative in-house assessments on identical panels.
| Parameter | SYLOID® ED 2lab-measured, purchased sample | Censil651lab-measured |
|---|---|---|
| Median particle size d50 (measured) | 4.3 μm | 5.0 μm |
| d50 spread, Δd50 | ±0.5 μm | ±0.3 μm |
| Pore volume | 1.8 mL/g | 1.8 mL/g |
| Specific surface area, N₂ | 320 m²/g | 265 m²/g |
| Oil absorption | 320 g/100 g (DBP) | 270 g/100 g (DBP) |
| pH (5% suspension) | 7.2 | 6.5 |
| SiO₂ content, dry basis | 99% | 99.2% |
| Surface treatment | Untreated | High-melting PE wax |
| Blushing after cure, 85% RH | Slight blushing ★★★☆☆ | No blushing ★★★★★ |
| Suspension in waterborne system, 7 days | Settles on standing | No hard sediment |
| Clarity on dark panel | ★★★★☆ | ★★★★★ |
| Surface smoothness (touch) | ★★★☆☆ | ★★★★★ |
| Matting efficiency at equal loading | ★★★☆☆ | ★★★★☆ |
Method notes: d50 by laser diffraction (Malvern); blushing rated after cure and conditioning at 85% relative humidity; suspension observed over 7 days in the waterborne system; matting efficiency compared at equal loading. Lab-measured values for the reference grade may differ from the manufacturer’s published specification.
Censil651 runs at d50 4.9 – 5.2 μm against Grace's published 4.5 μm for SYLOID® ED 2 — slightly coarser, in the same fine-touch band. The bigger difference is deliberate: Grace lists ED 2 as untreated, while Censil651 is wax-modified. That wax layer is what controls anti-settling and surface touch in a waterborne system, where an untreated silica is more prone to hard sediment.
Datasheet parity is the starting point, not the proof. A 1:1 replacement is confirmed on your own line: run the Censil grade at the same dosage as your current import, compare gloss at 60° and 85°, clarity on a dark panel, touch and can stability — then fine-tune dosage within ±0.3%. Typical evaluation cycle is 1–2 weeks, and we ship a free 2 kg sample with a 1:1 benchmark sheet for exactly this.
The target is the finish, not the datasheet. The wax modification is what makes the grade behave in a waterborne system — it is the parameter behind anti-settling and touch. Run Censil651 at your current ED 2 dosage and compare gloss, clarity and touch on your own line.
No special equipment is required. Add the matting agent after resin letdown under moderate shear, as you would with any fine-particle silica.
Grace does not publish a numerical pore volume or BET surface area for ED 2 in its EMEA product properties table. Censil651 is published at 1.6 – 1.8 mL/g and 250 – 280 m²/g.
The wax modification is specifically what addresses this. Ordinary untreated silica can hard-cake at the bottom of the can; verify on your own formulation with the free 2 kg sample before you commit.
20–30% below imported pricing, factory-direct. First orders are flexible at 500 kg to 1 ton rather than a full container.
Send your resin system, target gloss and the grade you use today. We’ll ship a free 2 kg sample with a 1:1 benchmark sheet against SYLOID® ED 2, the relevant TDS. We reply within 24 hours.
Request a Free 2 kg SampleACEMATT® is a registered trademark of Evonik Industries AG. SYLOID® and GRACE® are registered trademarks of W. R. Grace & Co.-Conn. Censilcoat is not affiliated with, endorsed by or sponsored by Evonik or W. R. Grace. Trademarks are used solely to identify the reference products a customer may currently use, for comparison purposes. Reference-grade figures are reproduced from the manufacturers’ published documentation as cited and were current on the page date; manufacturers may revise specifications without notice. Censil figures are typical guidance values — the controlled specification per grade is stated in the grade TDS. Performance must be verified by the customer under their own conditions.