What is scrub resistance?

Scrub resistance is the relative abrasion resistance of a coating during use when contaminants are removed by repeated scrubbing. This property is very important for architectural coatings, especially interior wall coatings, and is an important indicator for measuring the quality of coatings.

Why scrub resistance is important?

The higher the scrub resistance, the more binder the coating contains, which indicates better physical properties of the paint. High-quality paint, even after multiple washes, can still maintain a good appearance and performance. In contrast, products with poor scrub resistance are prone to issues like coating falling off and powdering. With frequent cleaning, the underlying surface may become exposed, losing both the protective and decorative properties of the paint.

1. GB/T 9266-2009 Determination of scrub resistance of film of architectural paints and coatings This standard applies to the determination of the scrub resistance of architectural coatings (flat surface). It provides detailed descriptions of the testing principles, required instruments and equipment, key operational points, result representation, and other relevant content to ensure the reliability and repeatability of the test.

2. ISO 11998:2006 Paints and varnishes — Determination of wet-scrub resistance and cleanability of coatings 

3. ASTM D 2486-2017 Standard Test Methods for Scrub Resistance of Wall Paints

4. ASTM D 3450-2015(2020) Standard Test Method for Washability Properties of Interior Architectural Coatings

5. ASTM D 4213-08(2016) Standard Test Method for Scrub Resistance of Paints by Abrasion Weight Loss

6. ASTM D 4828-1994(2020) Standard Test Methods for Practical Washability of Organic Coatings

Instrument requirements

● Straight Line Washability Machine.

● Weights of nylon bristle brush and accessories: 454±10g

● Drawdown plate: 454×165×6.3mm

● Brass shims: 12.7×0.25mm

● Speed: 37±1 cycles/min

How to do a scrub resistance test?

1. Soak the bristle brush overnight

2. Place the test panel with applied coatings in the abrasion scrub tester

3. Apply 10g of the abrasive scrub medium to the brush. Place the brush at one end of the path and then wet the panel with 5ml of water in the path of the brush.

4. Power on the abrasion scrub tester and then brush starts scrubbing on the test panel.

5. Record how many cycles it takes to remove a continuous thin line of paint film across the 12.7-mm (1/2-inch) width of the shim. Stop the machine and wipe the shim area to check, if needed, whether the endpoint has been reached.

The launch of the latest AI Wet Abrasion Scrub Tester by BEVS not only reflects the trend of continuous innovation in the laboratory analytical instrument industry, but also meets the needs of modern enterprises to improve the efficiency and accuracy of testing:

● Integrate advanced AI technology, featuring a large touch screen and voice control for remote operation

● Use a dual-channel design, automatically applying solution (abrasive scrub medium) to the brush

● Equipped with a high-definition camera, it can automatically monitor the scrubbing resistance of the test samples, eliminating the need for manual visual recognition.

● Automatically recognize the length of the exposed area after scrub and record the number of scrubs

● Compatible with a wide range of friction heads in accordance with GB, ISO, ASTM, DIN and other standards

The BEVS 2806H AI Wet Abrasion Scrub Tester is an indispensable tool for quality control and product development as it provides consistent and reliable test results by precisely controlling the scrubbing force, speed and number of scrubs.