The Hot-Box process is used to mould full cores. The bonding reaction is exothermic, which helps further reinforcement process after the removal of heat source. Cores made in this technology are used in iron and aluminium casting (urea-furfural resins) and steel casting (phenolic-formaldehyde resins). The curing of resin is done in the core box preheated to 150-220ºC, depending on the applied resin. The preparation of cement composed of quartz, resin and curing agent is done before injection into the core box. The time that the material stays in the core box depends on the core wall thickness, mass composition and the type of used resin; it usually varies between ten to fifty seconds. This process is particularly recommended for the serial production of cores, as it requires accuracy and repeatability of dimensions and shapes, adequate strength and de-coring.