Polished Concrete and timber are often used as a flooring base for home, workplace or in public areas. On their own they provide reasonable aesthetic and durability properties. However these are dramatically improved when a high quality floor coating is applied.
Timber and polished concrete coatings can be available in a range of finishes including gloss, satin & matt. A non-yellowing floor coating will allow the natural beauty of the concrete or timber to be seen for years to come. The use of lower quality coatings will leave the owner will a floor that only looks good after it is first complete rather than admiring it years later and being proud of the floor and the quality of workmanship. High grade coatings cure to be totally inert after application and are non-yellowing. They are suitable for interior and exterior use. The best of epoxies and polyurethanes are extremely durable and resistant to a wide variety of insults. These include foot traffic, machine traffic for example cars, trucks and forklifts, chemicals such as weak acid, oils, brake & radiator fluid, minor impact from tools and equipment, and can be food grade rated.
Another area of major importance is the ease of application and recoating. The coating needs to have very high adhesion to substrate primers and intercoats, be fast curing in a wide range of temperatures, have a comparatively low smell and provide a build level using 3 coats on a new surface and 1 to 2 coats when recoating. A high end coating is also expected to adhere well to concrete coloring techniques for example colored acid stains.
Even though there is a move away from epoxies to polyurethanes, some epoxies are used as a primer due to their excellent adhesion and water resistance properties. Epoxies provide an excellent surface for a topcoat to adhere to and provide a protective barrier to the topcoat. Combining the use of epoxy and polyurethanes enables the best qualities of each to be used. The excellent adhesion and water resistance properties of epoxy combined with the good cure speed, excellent abrasion resistance and gloss retention of polyurethanes prolong coating life. This produces a well adhered, durable and aesthetically pleasing coating.
There are many forms of coating products. They can be either single or two pack (also known as 2k), water or solvent based. Each helps fit specific requirements as it is difficult to meet all the final requirements from one coating. The single pack non-yellowing polyurethanes provide an ease of use product, however are solvent based. This is not a concern for most applications, however for applications where ventilation is difficult or the premises cannot be evacuated during application and cure, such as a shopping centre, these are not suitable. Currently the 1k non-yellowing provide the highest gloss level of all the coatings. Two pack products require precise mixing ratios and effective stirring to allow the product to properly cure. Hence the 2k products are generally used by the professional. There is however more and more DIY using them as the instructions and pack sizes make it easier to mix, i.e. the addition of Part A directly in Part B ensure correct ratio mixing. Solvent based two pack colored systems have superior mechanical properties, increased chemical resistance and long term resistance to environmental degradation. These are generally used in industrial applications such as warehousing, workshops or high traffic areas. Water based 2k products are more for retail applications as there is a requirement for low VOC as shopping centres are constantly manned. We are finding that there is a move to use more water based 2k non-yellowing clear coatings in domestic homes as consumers desire to be more environmentally friendly and reduce the amount of VOC’s entering the atmosphere. With ever changing technology the advance in these water based systems may see the end of the solvent based 1 part. But until they can match the full gloss level this may be a few years away.