What is a primer?

Primers are an important component in tiling as they improve the bonding of the tiling system, as well as improving the working characteristics of an adhesive. Inadequate or incorrect surface preparation is the most common cause of failure when bonding tiles onto surfaces.

What are the benefits of using a primer?

Good primers regulate the absorption rate of tiled surfaces. This results in:

Better water retention leading to longer curing and therefore higher ultimate strength. Adhesives that dry too quickly never gain full strength and can become brittle.

Increased open time for the adhesive which means more adhesive can be spread and more tiles can be laid.

Hydroxypropyl methyl cellulose (HPMC) is a non-ionic cellulose ether obtained by cellulose alkalization, etherification, neutralization and washing. HPMC has good thickening, dispersing, emulsifying, film-forming properties, etc. It is the first choice for production of high quality building materials additives.

For Wall Putty/Plaster

Other benefits of primers include:

A significant improvement in the bond of tile adhesives. Primers penetrate into the bare surface further than adhesives and also seal any difficult to remove dust.

An increase in the adjustment time of tiles after they have been placed on the wet adhesive. So if a tile is out of line you have more time to adjust it.

An increase in re-flow times for floor levellers

A reduction in pin holing in waterproofing membranes

Do I need to use a primer?

Yes, with the exception of substrates covered with a waterproofing membrane due to its non-absorbent nature. We recommend the use of a primer on all other substrates to be tiled. By not using a primer, you can void your product and tiling system warranties.

What is the effect of high temperatures on primers?

With high temperatures, primers can evaporate very quickly (known as “flash drying”) before they have penetrated the pores of the material to control porosity and trap embedded contaminants.

 HPMC for Tile Adhesive     

What is efflorescence?

Efflorescence is a concentration of salts (calcium hydroxide) present in all cements and other mortar constituents such as sand aggregates and lime which move through grout joints to the surface. Once this concentration reaches the surface, it reacts with the carbon dioxide in the air forming “Calcium Carbonate”. This then dries leaving behind white crystals which discolour the grout.

Efflorescence is more prominent in winter months as the weather is colder and moisture more prevalent. It is more noticeable on darker grouts due to the colour contrast.

How can I contain or reduce efflorescence?

The key is to avoid excess water throughout your tile installation system. You should use fast setting adhesives such as 1 Part Rapid or 2 Part Rapid and use a low efflorescence grout. Be sure to reduce the amount of water used in clean-up and avoid early clean-up of grouting. Allow grout to set fully for 24 hours prior to cleaning grout haze.

In building materials, the addition amount of HPMC is very low, only 0.1%-1%, but it plays an irreplaceable role and can significantly improve the water retention, fluidity and lubricity of building materials. Building materials added with HPMC are easier to mix and use, improve the work efficiency of construction workers, extend the open time, improve the bonding strength, and form a smooth and delicate surface coating.