The liquid coating is applied to the surface of the object to be coated and changes from a liquid state to a solid coating film, that is, the time it takes to dry and form a film through a physical or chemical process.
The coating industry customarily divides the drying process into three stages: surface dry, solid dry and complete dry (foreign standards are divided into more stages, such as ASTM D1640 in the United States).
For coating construction, the shorter the drying time of the coating film, the easier it is to ensure the drying quality of the coating film, especially in field or outdoor coating construction, that is, this kind of coating has better applicability.
Since the drying process of the coating film and the drying time of the coating film are related to the construction environment and construction process time, and most of them are a slow and continuous process, an automatic drying time Tester can be used. Surface dryness, also known as finger-touch dryness, means that the coating film is not sticky when lightly touched with a finger. /T 6753.2-86 "Small glass ball method for coating surface drying test". Dry hard, that is, push the coating film with fingers, and the coating film will not move. The test method is GB/T 1728-88.
