Process and coating colour for coating of paper and board

The present invention concerns a process and a coating colour for coating a cellulosic web. According to the process an aqueous coating colour is applied on the surface of the web. The invention comprises using a coating colour which contains an aqueous polymer whose viscosity in an aqueous solution increases when the temperature rises. Preferably, methylcellulose or a corresponding polymer having a gelling temperature of about 5 to 10 DEG C more than the application temperature of the coating colour is used. The temperature of the coating is increased after the application of the coating colour in order to achieve gelling of the polymer. As a result, the coating colour rapidly solidifies which decreases the amount of mixture being recycled and it reduces mist-formation in the film press method and improves coverage of coating applied by conventional blade coating.