As the outer protective layer of various products, the coating film will be affected by a variety of factors during use, one of which is the influence of light, heat and electricity. Yellowing is a common problem in the case of oil in the film. Yellowing will not only affect the appearance of the film, but also may damage the quality of the product and market competitiveness. In order to solve this problem, we need to test the yellowing resistance of the film, this paper will introduce the importance of yellowing resistance and detection methods, especially the instrument determination method using GB/T 11186.2 method.

concept

Yellowing resistance refers to the ability of the film to resist yellowing during use. This property is particularly important for coatings containing oils, as the oils may generate yellow decomposing substances during drying and oxidation, resulting in yellowing of the film. Yellowing will not only destroy the appearance of the product, but also may cause consumer dissatisfaction and reduce the market competitiveness of the product. Therefore, evaluating the yellowing resistance of the film is crucial for manufacturers.

Resistance to yellowing of film and its determination

Detection method

In order to evaluate the yellow resistance of the film, the provisions of GB/T 11186.2 are usually used, which is an instrument-based method. Here’s how to do it:

Prepare the coating template to ensure that it meets the product requirements, especially the color requirements.

Place the template in the appropriate position in the color difference meter to ensure that the light source is stable.

Measure X, Y, Z values of the sample using a color difference meter.

Based on these measurements, the yellowing value D is calculated by the formula D=(1.28X-1.06Z)/Y.

According to the calculated D value, the yellowing resistance of the film can be evaluated. The lower the D value, the better the yellowing resistance of the film and the smaller the color change. On the contrary, the higher the D value, it indicates that the film is prone to yellowing.

Resistance to yellowing of film and its determination

Application field

The yellowing resistance test of coatings is widely used in many application fields. In the field of home decoration and construction, the yellows resistance of wall coatings is critical because they are usually in bright light and need to maintain color stability for a long time. In the automotive industry, car painting also needs to consider yellowing resistance to ensure that the body color will not fade due to ultraviolet radiation. In addition, the coating of the electronic product shell also needs to have good yellowing resistance to maintain the appearance quality of the product.

conclusion

Yellowing resistance of the film is one of the key properties to ensure the appearance and quality of the product. In order to evaluate the yellow resistance of the film, the instrumental method of GB/T 11186.2-89 provides an accurate and repeatable method. This detection method has a wide range of applications, helping manufacturers to provide high-quality, durable products that meet consumer needs for color stability, while maintaining brand reputation and market competitiveness. Therefore, the research and detection of yellowing resistance is of great significance in the field of coating detection.