Arcwood SL 260 Two-Component Grain Filler and High-Build Sealer
A two-component, isocyanate-cured polyurethane grain filler and sealer with high solids and high film build, formulated to fill the open vessels of teak, oak, ash and similar species in one or two coats. Because it cures chemically rather than by solvent release, it shrinks less as it hardens and does not sink back into the pore as the panel ages.
Grade Arcwood SL 260 | Range Wood and Furniture Coatings | Technology Two-component solvent-borne polyurethane, cured with an isocyanate hardener
Technical Data Sheet
Arcwood SL 260
Issue 2026.09
1. Product description
An isocyanate-cured polyurethane sealer with high solids and high film build, formulated to fill the open vessels of teak, oak, ash and similar species in one or two coats. Because it cures chemically rather than by solvent release, it shrinks far less as it hardens and does not sink back into the pore as the panel ages, which is the usual cause of a patchy sheen appearing weeks after despatch. It is the high-build member of the SL family and the correct base under Arcwood PU topcoats on open-pore work.
2. Features
- Fills open-pore species in 1 to 2 coats at 40 to 60 microns dry per coat
- Chemical cure with low shrinkage, so the pore fill does not sink back after despatch
- Sandable after 4 to 6 hours with 320 to 400 grit
- Base under Arcwood PU topcoats on open-pore work
- Used where the finished surface will meet water, alcohol or cleaning agents
3. Recommended uses
Grain filling and sealing of teak, oak, ash and mahogany solid timber and veneer, filled profiles on MDF edges and particle board carcass faces, under two-component polyurethane topcoats on furniture and joinery.
Substrates. Open-pore solid timber and veneer, teak, oak, ash and mahogany, MDF edges requiring a filled profile, particle board carcass faces.
4. Typical properties
| Property | Typical value | Method |
|---|---|---|
| Technology | Two-component solvent-borne polyurethane, cured with an isocyanate hardener | Formulation |
| Appearance | Liquid sealer, curing to a sandable high-build film | Visual |
| Non-volatile content by mass | 50 to 60 per cent, high-solids grade | ISO 3251 |
| Application viscosity, mixed with hardener and adjusted, 4 mm flow cup at 30 degrees C | 14 to 25 s | 4 mm flow cup, customer or supplier protocol |
| Pot life at 30 degrees C | 3 to 6 hours | ISO 9514 |
| Dry film thickness per coat | 40 to 60 microns | ISO 2808 |
| Time to sand at 30 degrees C | 4 to 6 hours | customer or supplier protocol |
| Cross-cut adhesion | Classification 0 to 1 on correctly prepared substrate | ISO 2409 |
| Timber moisture content at application | 8 to 12 per cent | EN 13183-2, electrical resistance method |
Typical values, not a specification. Values for each batch are given on its Certificate of Analysis.
5. Application
| Parameter | Guidance |
|---|---|
| Mixing | Mix the base with the supplied hardener at the ratio stated on the label, and mix only the quantity the shift will use within the pot life of 3 to 6 hours at 30 degrees C. |
| Surface preparation | Sand timber and veneer to 180 to 240 grit with the grain and remove dust with clean compressed air or a tack cloth. On teak and other oily species, wipe with the thinner specified for the grade and let it flash off before sealing, because natural oils in the timber can retard the cure and weaken adhesion. |
| Thinner | Adjust the mixed material to 14 to 25 s on a 4 mm flow cup at 30 degrees C only with the polyurethane thinner specified for the grade. Alcohol-containing thinners react with the isocyanate hardener and are not used. |
| Film build | Spray 1 to 2 coats at 40 to 60 microns dry per coat on teak, oak, ash and similar open-pore species |
| Sanding | Allow 4 to 6 hours at 30 degrees C, longer in a cooler shop, then cut back flat with 320 to 400 grit to level the pore fill and give the topcoat a mechanical key |
| Shop conditions | Work between 15 and 35 degrees C with relative humidity below about 70 per cent. |
| Overcoat | Arcwood PU topcoats, within the recoat window confirmed for the grade supplied |
Process. Mix with the supplied hardener, spray 1 to 2 coats at 40 to 60 microns dry per coat. Allow 4 to 6 hours before sanding with 320 to 400 grit. Overcoat within the recoat window stated on the technical data sheet.
6. Storage and handling
Store base and hardener in their original, tightly closed containers in a cool, dry, covered area out of direct sunlight, keeping the hardener sealed against moisture. Shelf life is stated on the label and Certificate of Analysis. Handle and use the product in line with its Safety Data Sheet.
7. Safety and regulatory information
Read the Safety Data Sheet before use. Safety Data Sheets and regulatory declarations are issued by our technical centre against the product and batch supplied, so they are sent on request rather than published. Request a Safety Data Sheet or declaration.
This Technical Data Sheet is published for on-screen reference. The information is given in good faith from laboratory and application experience and describes typical values; it is not a specification and does not replace a trial on your own substrate and line. Arctic Materials may revise this sheet without notice. Issue 2026.09.
Technical Data Sheets on this site are for on-screen viewing. For a controlled copy, write to tech@arcticmaterials.com.
Other grades in this range
Need a Safety Data Sheet, a regulatory declaration or a grade specified to your line? Contact our technical centre.