Abstract: Device for performing the wetting operation for offset printing, comprising a main receptacle (1) which contains a wetting solution; an outlet pipe (2) with a pump (3) which pushes the solution towards an outlet nozzle (4) to project it inside a recipient (5) housed in the main receptacle; a feed pipe (6) which joins said recipient to the wetting system of the offset printing machine; and a pipe (8) through which the wetting solution returns to the main receptacle. The outlet pipe of the solution has a Venturi device (9) whose main pipe (14), through which the wetting solution passes, forms part of said outlet pipe and has at least one side air-intake pipe (10) joining the main pipe at an oblique angle.

Abstract: Humidifying solution for offset printing sheets and method and device for its preparation. The solution is formed by between 95% and 97% of water and between 3% and 5% of an additive which contains sodium citrate, acetic acid, citric acid and sodium benzoate, characterized because the aforementioned additive contains between 0.0% and 0.5% in weight of sodium hexametaphosphate, between 0.0% and 1.5% in weight of ascorbic acid, between 0.0% and 1.0% in weight of preventol, between 0.0% and 1.0% in weight of sodium benzoate, between 0.0% and 1.0% in weight of citric acid, between 2% and 10% in weight of glycerin, between 0.0% and 0.1% in weight of limonal, between 50% and 75% in weight of sorbitol, between 1% and 2% in weight of acetic acid, between 3% and 7% in weight of citric acid, between 0.0 and 1.0% in weight of sodium oleate and between 15% and 30% in weight of osmotic water.

Abstract: Humidifying solution for offset printing sheets and method and device for its preparation.

Abstract: A wetting system is supplied with a water based solution including a determined additive. This solution is subjected, through a mechanism, to a process of agitation by which it adsorbs a high oxygen content. As a result of these improvements, the solution which wets the aluminium plate, from which the printing is done, acquires a high free oxygen content, increasing the water-ink interface and improving the quality of the printing.

Abstract: The improvements consist in supplying the wetting system with a water based solution including a determined additive. This solution is subjected, through a mechanism forming a part of this invention, to a process of agitation by which it adsorbs a high oxygen content. As a result of these improvements, the solution which wets the aluminium plate, from which the printing is done, acquires a high free oxygen content, increasing the water-ink interface and improving the quality of the printing.