CERAMIC GRITS: DEVELOPMENTS, APPLICATION EVOLUTIONS AND CHEMICAL RESPONSES
The ceramic industry has recently shown an interest in some of the latest generation glass grit, to be used as final cover on all those products - tiles or slabs - that are subsequently destined for lapping or sanding process.
In fact, some types of grits with a very low content of fine residue and with much higher granulometry than the standards used untill now are entering the market.
What is the origin of this interest?
The coarser grit, in addition to being used in possible dry applications, in same cases would allow to obtain aqueous suspensions with very high densities. They are also able to optimize the features of the final glass after firing and to reduce the porosity after polishing.
Although there are no significant cases yet that could confirm and validate the above benefits, some interesting results seem emerging.
What are the chemical implications with respect to this different type of grit?
If used for wet applications - and this is certainly the predominant case - the water composition in which the grit is located (the suspension) must be modified.
In other words, new formulations are needed that are capable of correclty managing the suspension of the grit and at the same time guarantee the appropriate quality of application.
As always, chemistry plays a crucial role in the success of production processes.
In this specific case, new and different rheological studies were necessary to solve the problems related to phenomena of rapid and uncontrolled sedimentation.
It will be plain to everyone that the larger size of the grit facilitates and speeds up that process.
Therefore, some new generation mediums have been developed with a much higher suspending power than the ones used for the finest grits.
With their levelling power, they also ensure excellent performance in terms of application.
The special formulation ingredients act sterically on the system without interfering with the viscosity during application: the system has a very low viscosity in the atomisation phase, while it has a high flow limit that guarantees excellent suspension in the static phase.
Back to How To