Expectations from textile products are increasing day by day. Features such as water, oil and dirt repellency are now more prominent. During the 1990 years, the leaves of plants which have very good water repellency properties were examined and their hydrophobicity was revealed. Since then, hydrophobic surfaces have been developed for textile products depending on the possibilities in the technologies. In the textile industry, it is very important to protect the fabric from getting wet in improving the resistance of fabrics against water or dirt.

The basis of the water repellency treatment of fabrics is to form a very thin hydrophobic membrane on the fibers. The water repellent fabric provides certain protection against wetting. However, in the event of prolonged and severe wetting, the fabric still contains water.

Tests for detecting surface wetting strength in textile products are mostly applied in topcoats, overcoats and dress fabrics. There are three common methods for waterproofing and water repellency testing of fabrics: the Bundesman sprinkler test, the spray test and the Schopper test. The first two tests are carried out to determine the resistance of the fabric against sprinkling. The third test is to test the waterproofness of the textile material under pressure. The water repellency test is carried out with the Bundesman sprinkler test in the most precise manner. However, spray testing is also a common method.

In the spray test, the fabric sample is held taut on an inclined plane and sprinkled in a controlled manner. The fabric is then evaluated.

For physical tests performed in accredited laboratories, standards issued by local and foreign organizations are complied with. In this context, the following standards are taken into account in spray tests:

• TS EN ISO 4920 Textiles - Fabrics - Determination of resistance to surface wetting (spray test)
• AATCC 22 Water repellency: Spray test (Test method 22)