Exterior Polyurethane

ICA 2k Solvent Polyurethane System for Exterior Use

Although now generally substituted by water based products due to ease of maintenance and the difficulty of fully protecting the entire article, the solvent systems still have a role in exterior protection. Suitable for outdoor furniture, windows, doors, gazebos and basically anything wooden that needs to be protected both from the elements and rigours of daily use. The ICA IS207/LP157 system provides a clear coating that will help resist scratching & marring whilst also enhancing and protecting the beauty of the wood.

Exterior 2K PU System Description

If staining, we recommend the use of the CNA water based stains, or CNS solvent stains - ensuring they are completely dry prior to commencing work.

If necessary, reduce with D1010 or D1015 (for example when applying by brush).
For high gloss, we recommend IS207/C207 & LAC367/C200
Consult your distributor for full information prior to starting any project.

Summarised Suggestions for IS207/LP157
series of polyurethane for exterior use

1) On a sanded wooden substrate (typically with 180 grit) apply IS207 catalysed with C207 at 1:1 ratio. Whilst dilution is not normally necessary, to avoid blow back & to ensure good wetting of wood with deeper pores, IS207/C207 may be reduced at 10 to 50% with D1010 or D1015. Application rate should be 2 to 4 wet mils.

2) We suggest application of a second coat of IS207/C207, preferably unthinned after an interval of at least two hours and no more than 4 hours at 73F (without sanding) at 3 to 5mils.

3) After a further interval of at least 8 hours (at 73F) sand with 280/320 paper & apply a coat of LP157 catalysed at 1:1 with C157 ((ie 100 parts LP157 to 100 parts C157) or C153AP at 2:1 (ie 100 parts LP157 to 50 parts C153AP) and diluted at approx. 10% to 20% with D1010 or D1015.Using pneumatic equipment we suggest air pressure of 2 to 3 Atm with a nozzle of 1.6 - 1.8mm.

4) Depending on exposure, grain fill required, wood type etc., a second coat of LP157 may be required after 2 to 6hours without sanding. A further coat may be applied after the same interval. We do not recommend exceeding 3 coats of the LP157 series without sanding.

5) For full fill, a further 2 coats of LP157 may be applied after sanding the LP157 as applied in step 4 after those coats are allowed to dry overnight (at least 12 hours at 73F - presuming 3 coats were applied at that time).

WARNING: The film of LP157/C157 will yellow slightly over time, so to minimise this & also increase elasticity use C153AP. This cycle is not recommended for exotic woods such as teak & ebony. Consult your distributor for full information prior to starting any projects. In all cases, preliminary trials should be conducted to determine suitability prior to starting production.

Note: IS207 and LP157 can also be applied using brush or roller - application information given above applies to spray. Temperature is assumed to be approx 73F & RH of 60%. Coating times and intervals are based on these parameters. If moisture is allowed to penetrate from behind the film, film failure, blooming or other problems will probably result.

WARNING:
Catalysts contain a small amount of iso-cyanate – ensure proper precautions are taken.

Sample Procedure for Repairing Exerior Solvent Borne Polyurethane

• Sand damaged area with 280 or 320 grit until sound coating is reached.
• Apply one coat of LP157/C157 of the desired sheen diluted at 30 – 40% if using a brush or 10 – 30% by spray
• Wait between 1hr & 2hrs & apply a further coat if necessary

If sanding goes through to bare wood, in some very small areas, the procedure is still as above. If however there are slightly larger areas, then sand damaged areas with 150 – 180 grit & apply one coat of IS207/C207 diluted 10 – 20% onto the uncovered, bare wood areas. Wait at least 4 hours, sand with 280-320 grit & apply LP157/C157 as above.

Should there be major degradation, to avoid halos & other imperfections, it is advisable to sand down completely & re-do the complete system.

Important Notes & Health and Safety Warnings

Consult the relevant TDS & MSDS for mixing ratios etc. The catalysts C207 & C157 contain small amounts of TDI – ensure adequate ventilation & OSHA approved masks – see MSDS

Always verify the suitability of the product for the job to be done before application. Once mixed, the products have a pot life restraint – depending on conditions probably from 2 – 4 hours - ensure the products are used within their pot life.

ICA products are for industrial, professional use only.

LP157I = matt

LP157M = semi-matt

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