We’re now, for many reasons, seeing an inexorable march away from spirit-based sealers. While some prefer the finish provided by a ‘solvent’, the case for their use is, quite literally, being watered down. Richard Osborne explains.
IN the tiling sector, the discussion centres on impregnating sealers – and whether a water-based product can provide the same performance as a spirit. Spirit-based sealers – often referred to as solvents or oil-based based products – contain a significantly higher level of organic solvents than water-based treatments.
They create that strong odour that’s evident when a surface has been freshly sealed but, if incorrectly used, they can also be potentially hazardous and harmful to the environment.
What do spirits do – and are all water-based sealers spirit-free?
The term ‘solvent’ can be confusing because water is, itself, a solvent. The traditional sealers which are spirit or oil-based are often referred to as ‘solvent-based’, so it’s often clearer to use the term spirit-based.
A spirit facilitates a sealer’s application, its drying and the formation of an even seal below the surface of the tile or stone. During application and drying, it evaporates and releases volatile organic compounds (VOCs) into the atmosphere, so a fully cured sealed floor no longer contains spirit. To achieve an optimum seal with a spirit-based sealer, surfaces should be completely dry before application.
Historically, the molecules of the spirit carrier were smaller than water, so they tended to penetrate dense surfaces more quickly and more deeply, which in turn provided a better quality seal. This, however, is no longer the case.
Extensive research and development into water-based sealers, coupled with increasing withdrawals of solvent based raw materials, has created a new breed of high-quality water-based sealers that are equal to or superior to their spirit-based equivalents. They offer excellent durability, quick drying times, an odourless application and they can be applied over residual moisture. Not all water-based sealers are completely spirit-free. Many contain ‘co-solvents’ – solvents present in lower concentrations that are meant to help push the rest of the water out of the coating as it dries. But since water-based solutions are either spirit-free, or contain considerably less, both provide a safer alternative to a traditional sealer.
Once applied and cured, water and spirit-based sealers function in a similar fashion. They are both tough and durable, they provide stain protection and they’re generally fully formulated and ready-to-use, so they’re easy to apply. One key difference is their appearance: spirit-based sealers tend to be clear as the sealer polymer and the spirit form a continuous clear solution, whereas some water-based sealers appear milky.
This is because the polymers are present as separate particles and scatter visible light differently than the water in which they are dispersed. The milky appearance of a water-based sealer disappears as soon as the treatment cures.
In terms of environmental advantages, the water-based products win hands down. Being low VOC and low odour, they’re less toxic, less harmful to the environment and to human health. This is especially relevant for internal projects and a growing number of organisations now have sustainable maintenance policies in place relating to zero carbon and the use of toxic spirits. Less obvious benefits include easier transportation, handling, and storage, as water-based products are non-hazardous/non-flammable.
They also offer greater UV resistance; water-based sealers are fully transparent to UV light, so they do not undergo the photochemical breakdown experienced by some more UV-absorbent spirit-based sealers. And, as a general rule, water-based sealers tend to go further than solvent-based sealers, with a typical extra coverage of between 10 and 20% on most surfaces. What’s not to love!
Within our own ECOPROTEC interior and exterior ranges, we offer water-based treatments for sealing & protection, cleaning & restoration and aftercare of polished and unpolished natural and artificial stone, porcelain, ceramic, concrete, masonry, and terrazzo.
The treatments are made in the UK, feature low odour and low VOC formulations and the range benefits from the most advanced research in water-based technology. It’s fair to say that spirit-based products do still currently represent most sales in the flooring and tiling industries but sales of water-based products like our own continue to grow year-on-year.
Of course, the move towards water-based products isn’t completely conscience-based. There are other factors at play. Current economic uncertainties and the increasing cost of hydrocarbons are creating greater demand for water-based solutions. At the end of the day, price is always a big driver but, in this particular case, it’s creating a further wave of change.
Richard Osborne is managing director, LTP