Film plays an important role in various Applications. It not only provides a beautiful appearance for the product, but also undertakes the task of protecting the substrate. During the use of film, it will be affected by many factors, including external force, light, heat and electricity. Among them, the action of ray of light has a significant impact on the light retention of film. This article will introduce the light retention of film and its detection method to meet the needs of different products.
Light Retention of Film
The light retention of a film is the ability of the film to retain its original Gloss under exposure to rays of light. This performance is critical in a variety of applications, as maintaining Gloss not only makes the product look more attractive, but also prolongs the life of the film. To assess the light retention of a film, it is usually measured using the light loss ratio, which refers to the ratio of Gloss after irradiation to Gloss before irradiation.
Detection method
The light retention of the film can be determined by the provisions of GB/T9754-2008 "Determination of 20 °, 60 ° and 85 specular gloss of Paints and varnishes Paints paint films without metal pigments". The following are the specific operation steps:
Prepare the test film template.
Cover part of the sample to ensure that the part under test is not exposed to rays of light.
The test sample is placed under sunlight or artificial Light source for a certain period of time to simulate the actual use conditions.
Gloss values of unirradiated and irradiated portions were determined using an optoelectronic Glossmeter.
Calculate the light loss rate, that is, the Gloss value after irradiation divided by the Gloss value before irradiation.
According to the value of the light loss rate, the light retention of the film can be divided into different levels:
The light loss rate of less than 5% is 0, indicating that the film has excellent light retention and almost no Gloss loss.
5%~ 20% is grade 1, indicating that the film has good light retention and small Gloss loss.
21% to 50% is grade 2, indicating that the light retention of the film is average and the Gloss loss is moderate.
51% to 80% are grade 3, which means that the light retention of the film is poor, and the Gloss is significantly weakened.
Greater than 80% is grade 4, indicating that the light retention of the film is very poor, and Gloss is seriously damaged.
Application
The light retention test of film is widely used in various industries, especially in fields that require a certain level of product Appearance, such as automobile manufacturing, furniture manufacturing, architectural decoration, etc. By testing the light retention of film, manufacturers can better understand the performance of their products and ensure that the product can maintain the attractiveness and mass of Appearance during use.
The light retention of film is one of the important indicators of product Appearance and performance. It can be affected by rays of light irradiation, so quantitative testing is required. GB/T9754-2008 stipulates the detection method of film light retention. By measuring the light loss rate, the light retention of film can be divided into different levels. This test method is of great significance in various Applications, helping manufacturers to ensure that their products can maintain Gloss in actual use and improve the competitiveness and mass of products. Therefore, the research and testing of film light retention is of great significance in the Coating industry.
