Use of compounds containing aluminium oxide and silicon oxide for producing a hydrophilic building product

A method for producing a hydrophilic building product by

• contacting with water, setting and curing, a binder system comprising compounds containing aluminum oxide and silicon oxide,
• wherein the binder system comprises hydraulic binder, latent hydraulic binder, and/or pozzolanic binder;
• and alkali metal silicate,
• wherein the hydraulic binder is selected from portland cement, aluminate cement and mixtures thereof,
• wherein the content of portland cement and/or aluminate cement in the binder system is ≦20% by weight, based on a water-free binder system,
• wherein the sum of the oxides calculated as Al2O3 and SiO2 in the binder system is ≧40% by weight, based on the water-free binder system, and wherein the contact angle of an oil drop placed on the surface of the cured building product is ≧90°, where the contact angle determination is carried out under water.