Antimicrobial coating

A process for producing an antimicrobial coating on a glass substrate, the process comprising the steps of:

• i) providing a glass substrate having a first surface and a second surface;
• ii) providing a silicon containing solution and a particle containing solution which comprises particles;
• iii) mixing together the silicon containing solution and the particle containing solution to form a silica coating composition;
• iv) contacting at least said first surface of the substrate with the silica coating composition to deposit a layer of the silica coating composition on the glass substrate;
• and
• v) curing the silica coating composition deposited on the glass substrate to form a silica matrix coating layer, wherein the particles are deposited on and/or within the silica matrix coating layer in an amount of from 0.1 to 20% by weight, resulting in an antimicrobial coated glass substrate;
• wherein the silica coating composition further comprises at least 1.0% by weight aluminium relative to the amount of silica in the silica matrix coating layer;
• wherein the particle containing solution comprises metal particles and/or metal agglomerates, and the metal particles and/or metal agglomerates comprise copper;
• and
• wherein the antimicrobial coated glass substrate provides at least a 2 log reduction against gram positive and/or gram negative bacteria within 2 hours at 37° C.