ITEM 51A

The “Spray Test” is used for the water repellency tests by spraying method on fabrics, leathers or other materials.
This instrument allows the operator to do water repellency tests to determine the behaviour of a fabric or leather to absorb water that get in contact with the same, in form of rain.
The exact definition for the test method is “Surface Wetting Spray Tester”.

INTERNATIONAL STANDARDS: ISO 4920, UNI EN 24920, BS 3702, AATCC 22, M&S P23, NEXT 23, UNI 5120, IUF 420, ISO 15700, etc.

The Spray test is supplied with:
– metal sprayer nozzles with 19 holes having the same diameter;
– laboratory extractable funnel;
– graduated plastic becher;
– test tube holder consisting of two rings where the tube is fixed;
– circular specimen holder placed at an angle of 45°;
– laboratory tray.

The water repellency test is performed as follows: the sample of fabric or leather is fixed in the frame, so that it is not bent, and then pour 250 mL of water at 20 ± °C in the funnel; so you will have a splash in the average length of 25-30 seconds. The water flows on the sample inclined at 45°. It then rotates the frame 180 ° and the test repeated.

The test determines the wettability index by comparison between the appearance of the test tube and that of the descriptive and photographic samples provided by the reference standard.
Visually the wettability index is evaluated according to descriptive (ISO) or photographic scales (AATCC).
The ISO index ranges from 1 (wetting of the entire surface) to 5 (dry surface).

This method does not provide information on the resistance to rain penetration.
To perform this test, the water column test is used.