Hychem SF20 — Heavy duty epoxy coating with good colour stability

Prior to the application of HYCHEM SF20, the substrate must be thoroughly prepared.

• The substrate must be clean and firm with a minimum compressive strength of 25MPa and a minimum surface tensile strength of 1.5MPa.
• The moisture content of the concrete must be below 5%.
• New concrete must be allowed to cure for minimum 28 days.
• In most instances, mechanical preparation is required.
• All dust, loose and friable material must be completely removed from all surfaces before application, preferably by vacuum.

It is important to note that even when the application environment is warm, products which have been stored in cold or cooler conditions should be pre-conditioned, ideally to 20-25°C, to ease mixing and application and help avoid other potential issues such as amine bloom or blushing. Applying a cold product in a warm environment is not recommended.

Add pigment pack to part A resin and mix thoroughly with a low-speed mechanical stirrer until complete uniformity is achieved. Add part B hardener and mix for 3 minutes ensuring the sides of the vessel are scraped to ensure no unmixed material.

Apply the mixed product at approximately 5-7 m²/L per coat over low porosity surfaces or 2-3 m²/L per coat over high porosity surfaces e.g. over a porous screed or where the base has been broadcast with aggregate. To assist workability HYCHEM SF20 can be diluted using Industrial Alcohol or Xylene at a maximum rate of 10-15% by volume where necessary. NB. this may affect pot life and cure times slightly.

Temperature and the surrounding atmospheric conditions will play a part in the curing process of all resin products. Under conditions of low temperatures and high humidity the final cured surface finish can be adversely affected, potentially resulting in poor gloss retention, discoloration over time, poor overcoat ability and inter-coat adhesion. Quite often these conditions will result in the formation of a white film over the surface, often evident after contact with water. If this occurs, the existing coating will need to be abraded to completely remove the affected surface to ensure the adhesion of subsequent applications. In some cases, partial or complete re-priming may be necessary. Attention also needs to be paid to the substrate temperature, which should be at least 3-5 °C above the dew point during the curing phase. Industry standards recommend the accurate recording of environmental conditions such as substrate and air temperatures, humidity levels and dew point readings during both the application and curing processes. Full material warranties cannot be provided unless all the relevant data has been recorded accurately. If in doubt consult the HYCHEM technical department for advice.

Wear appropriate personal protection equipment. Gloves, eye protection, mask and overalls should be used during mixing and application.

Minimum 12 months from date of manufacture when stored under shelter at 25°C in the original un-opened container.

The packaging must be stored properly in original, unopened and undamaged sealed packaging, in dry conditions at temperatures between 5°C and 30°C.

HYCHEM SF20 is supplied with pigment. As with most epoxy finishes, surface yellowing may occur on exposure to UV light from the sun or an artificial source. Any such discolouration has no effect on the performance of the product.

• Coatings and overlays containing water must not be applied directly to HYCHEM SF20 resin unless a sufficiently porous mortar has been installed or it has been fully broadcast with dry aggregate e.g. quartz or silica sand.
• Ensure consumption of material is uniform to achieve proper appearance, texture and consistent performance.
• Ensure the material is mixed and stirred properly. Incorrect mixing can lead to performance issues.
• If heating is required do not use gas, oil, paraffin or other fossil-fuel heaters. Use only electric-powered warm-air blower systems.
• At low temperatures and low humidities (< 40% relative humidity), curing and recoat times will be affected.