Pollution prevention method for canvas used in paper machine

1. A method of preventing contamination of a canvas for pressing a paper strip against a surface of drum-dryers used for drying the paper strip in a paper machine, whereby a silicone oil is emulsified with a surfactant, said emulsified silicone oil is diluted with water immediately before spraying, said water being heated to a temperature in the range of 50 to 80° C., and said diluted silicone oil is then continuously supplied at a spray rate of 0.1 to 200 mg/m 2 per minute to a surface of canvas rolls for guiding the canvas, in a stage of operation prior to the paper strip being pressed into contact with the canvas as well as the drum-dryers, while the paper strip is being fed by operation of the paper machine.

2. A method of preventing contamination of a canvas for pressing a paper strip against a surface of drum-dryers used for drying the paper strip in a paper machine, said method comprising the following steps 1) to 7):

1) emulsifying a silicone oil with a surfactant;

2) diluting said silicone oil with water immediately before it is supplied to a surface of an out-roll, said water being heated to a temperature in the range of 50 to 80° C.;

3) supplying said silicone oil to the surface of the out-roll at a spray rate of 0.1 to 200 mg/m 2 per minute;

4) shifting the silicone oil from the surface of the out-roll to the canvas;

5) causing the silicone oil to permeate through the canvas and adhere to the surface thereof under heat and pressure;

6) pressing a paper strip against the canvas, causing the silicone oil to be transferred to the paper strip; and

7) replenishing the silicone oil depleted after transferred from the canvas.