غسيل الفلم بعد التثبيت .. كتاب التحميض والطبع والتكبير

Wash the film after installation

After fixing the film, all traces of the solutions it went through in the previous steps must be removed from it, and removal is done by washing with water in one of the ways described in Ply:

A- If the dark room is ready to be washed in running water:

The film is left in the basin, and the water is renewed by placing a rubber hose that reaches from the tap to below the water level in the basin, so that the water is continuously replenished regularly and drained from the top. This process lasts about thirty minutes.

2- If there is no means in the Faseel Basin to drain the water in excess of a certain level inside the Basin:

To ensure the renewal of water during the washing process in this case, the following method can be used to drain the water.

It is a twisted metal tubing, as in (Fig. 137). Its longer end is placed in the drain, and the shorter end is slightly above the surface of the basin. When the water in the basin rises, the air is expelled from the tube and water replaces it (Fig.

Thus, the water continues to flow into the basin to ensure that the flag is washed with fresh water and the excess is drained. If the water level falls below the level of the shorter side of the pipe,
(Fig. 37-) The tube is devoid of water.

3- To wash sensitive films or boards while they are inside the tank (Fig. 38):

One end of a rubber hose is installed in the faucet, and the other end is placed at the bottom of the tank, with water draining from the top to ensure the movement of water from the bottom to the top in both cases (figure 37). It is sufficient to open the tap while it is above the tank, if the tank has a way to drain water from the bottom (the case is Figure 38).

Thus, we see that the two methods shown in (A, Figure (38) are not ideal for washing films, as water does not flow at that time in the lower parts of the tank.

4- Washing with cut films or delicate glass panels: (when they are inside a basin), it is better to lower the far side of the basin (Fig. A siphon made of a glass, metal, or rubber tube is placed in one of the sides of the basin (Fig. 39-b) after filling it with water (by mouth suction). The water comes out from the outer end as long as the inner end is submerged in water inside the basin.

5- If there is no running water in the laboratory:
If one of the previous methods is not available, then there is nothing wrong with doing the washing process in a basin whose water is changed every five minutes, six times in a row. Impurities may be attached to the pen if the wash basin is not clean, and here they must be removed by a rush of tap water with the help of a piece of cotton saturated with water (Fig. 40).