Italian machinery manufacturer Breton, which developed the plant used worldwide for making quartz composite as well as making a range of stone processing machinery, has developed a microwave curing line for the resin treatment of natural stone slabs. The first one has been installed at Cereser Marmi in Verona Italy and was scheduled to come on stream this month (October).

When resin is used to apply a mesh to the back of stone to reinforce it, or to fill voids in the surface of materials such as travertine, it is usually 24 hours before the stone can be processed because the resin needs time to cure.

The most widely employed systems make use of vertical static ovens with forced hot air ventilation to cure epoxy resins, and infra-red or UV ovens to cure polyester resins. The type of resin used depends on the material being treated (marble or granite) and the production capacity required.

For all resin types, hardening must be followed by a subsequent ambient temperature maturing stage of up to 24 hours to allow complete hardening of the resin before proceeding with slab polishing.

It is not the answer for every application because it heats to higher temperatures, which can cause fissures in some friable stones to open further. The resin also slightly yellows, which is not always desirable. But where it can be used it can save many hours of production time waiting for the resins to cure.