We talked to Pieter Pruyn, sales and product manager at Lecol BV. The main reason for our discussion relates to the new mandatory EU training sessions which became obligatory for professionals from 24 August onwards. Indeed, from now on, professionals are obliged to do a training course on the safe use of diisocyanates, especially for the use of products with diisocyanate monomers.

‘Basically, under the new legislation we can obligate clients to take those training courses, but at the same time you shouldn’t forget that there are also lots of other measures prescribed which floor fitters have to carry out. Such as, for instance, the protection of the hands. Do they do that?’ he starts. ‘I look at once at what we have in our range. Then, I also see various polyurethane products and 2K for wooden floors and PVC and then we notice that people are scared of PU now that the perception has grown that PU adhesives are not good for our health.’

Increasing restrictions
‘What do I think? It seems logical to me that these PU products are going to disappear in the long term, but it’s difficult to predict the exact time due to the increasing restrictions. For 2K PU adhesives, primers (PU primer also for damp insulation), and a repair product for repairing cracks we have di-isocyanate products which come under this law, but we’re certainly not in denial as regards the future. And so, in each case we say time and again that you can also switch to silane products just to be absolutely sure that you are working safely, and that applies to all three groups which I mentioned. We’re fully committed in this area and offer clients training sessions to secure our long-term future. Indeed, at Lecol and Wakol you can believe that it will be a logical decision to cut down the PU range.’

Offering a system
When we talk specifically about silane adhesives, Pieter Pruyn immediately says that it is important to offer a system. This means that professional users are given very precise guidance.
‘It all starts with the subfloor. You have to inspect it thoroughly before you can glue. Therefore, with our major products we provide training sessions and clear instructions,’ Mr Pruyn continues. ‘With a subfloor or screed you have to take account of a lot of parameters and they determine what the conditions are before you can glue. For instance, amongst other things, you have to insulate paint and product residue, insulate damp in the screed, etc. Very often in this case we’ve used Wakol PU 280, a polyurethane primer which has been on the market for over 20 years and can solve all problems, usually in two coats. Now we’ve further developed and refined that product and offer Wakol MS 330, a silane primer. We can use that for all operations in one coat as with the earlier product: insulating paint and product residue, applying a damp screen which dries in one hour, and reinforcing subfloors. You can guess the good news at once: There are no isocyanates or solvents in this product, so it is safe to use and, obviously, without any training. This is also a reactive product and also reacts to damp, but without the by-product isocyanate.’

‘When it comes to repairing cracks, I recommend Wakol PS 205, namely for movements which are so big that big cracks have to be repaired. This isn’t a PU, but a silicate resin also with isocyanate. We have other methods for working with polyester fleece, the Wakol AR 150 reinforcement fibre (fibre glass mixture), which we support with Wakol Z 640 quick cement. We don’t mix it with water, but with Wakol D3060 lamination. What happens is that we put reinforcement webbing on the crack and press it into the crack.’

What about PVC and parquet adhesives?
Mr Pruyn explains how PU adhesives are being replaced by MS adhesives. On the one hand we’re talking about PVC adhesives, and parquet adhesives on the other hand. For PVC they still use Wakol P 4270 PU adhesive for PVC outdoors or indoors in damp rooms, but this can be replaced by the MS Polymer Wakol MS 550: PVC and rubber adhesive. A 2K PU adhesive is thereby replaced by a safe 1K silane adhesive. For parquet adhesives we hear that at Lecol all PU adhesives can be replaced by four MS adhesives.

‘Firstly, I refer to the first among equals, Wakol MS 290: Parquet Adhesive chip resistant,’ Pieter Pruyn starts his list. ‘This is just as chip resistant as the 2K PU adhesive which we now sell. You can use it to glue any wooden floor, from cross-cut wood and traditional parquet to multilayer. In addition we have adhesives with a different price, including in the first row Wakol MS 260: Parquet Adhesive fixed elastic. You use this to glue everything, except for the old Flemish style. Another step back takes you to the Wakol MS 230: Parquet Adhesive elastic. You use that to glue only multilayer and small-size parquet floors. Finally, we still have Wakol MS 228: ready-for-use parquet adhesive elastic, which you can only use to glue multilayer parquet.’

Finally, Pieter Pruyn reminds us that there are so called connected systems for Wakol adhesives. Those systems guarantee that softeners never have irritating reactions if you combine them with lacquer or oil from Loba, which is 100% owned by Wakol. He points out that all adhesives are also EC1+ certified, and one is even IMO certified (editor’s note: suitable for boat builders). Mr Pruyn also mentions thixotropic adhesives for applications on the wall. These thixotropic adhesives are somewhat thicker, do not run out, and can be supplied in sausage packaging so that you can apply them standing up and working with an adhesive spray pistol.