Summary of drying time determination method for paint film and putty film

1. Introduction

The drying process of Coating is an important link that cannot be ignored in Coating construction. Coating drying time is directly related to the control of construction period, film mass and project progress. This paper will introduce the determination method of drying time for paint film and putty film, as well as its definition, purpose and significance.

2. Definition, purpose and meaning

Drying refers to the process of Coating changing from liquid film to solid film. The drying process of Coating can be divided into three stages: surface drying, actual drying and through drying. Usually, only the surface drying time and actual drying time of Coating are measured. Surface drying time refers to the time for the formation of liquid Coating surface film under the specified drying conditions. Actual drying time refers to the time when the entire liquid Coating layer becomes solid film under the specified drying conditions. Accurately determining the drying time of Coating helps the construction unit to control the construction period, and it is also an important means to ensure film mass.

3. Introduction of inspection methods

3.1 GB/T 1728 Determination of drying time of paint film and putty film

3.1.1 materials and equipment

Drying time Tester (drying weight)

Constant temperature and humidity equipment

Electric Forced Air Drying Oven

3.1.2 Operational Points

The surface drying time can be measured by blowing the cotton ball method or finger touch method. Method A (blowing the cotton ball method) is to gently blow the absorbentcottonph ball on the surface of the paint film. If it can be blown away without leaving cotton silk, it is considered that the surface is drying. Method B (finger touch method) is to touch the surface of the paint film with your finger. If it feels sticky but no paint is stuck on your finger, it is considered that the surface is drying.

The actual drying time can be measured by pressing filter paper method, pressing cotton ball method, blade method or thick layer drying method. Method A (pressing filter paper method) is to press the Tester on the paint film and remove it after 30 seconds. If the filter paper can fall freely, it is considered actual drying. Method B (pressing cotton ball method) is to press the Tester on the paint film and remove it after 30 seconds. If there are no traces of cotton balls and loss of light, it is considered actual drying. Method C (blade method) is to use a blade to scratch on the paint film and observe the bottom layer and film. If there is no adhesion phenomenon, it is considered actual drying. Method D (thick layer drying method) is to take the dried test block out of the aluminum sheet box. There should be no mucus at the shearing place. The shearing surface is closed and opened again, and there is no wire drawing phenomenon. It is considered actual drying.

3.1.3 result representation and result judgment

Record the maximum time required for the surface to dry, usually in hours or minutes. Whether to pass is determined according to the specified surface drying time.

Record the maximum time required for actual drying, usually in hours or minutes. Whether to pass is determined according to the specified hard drying time.

4. Application and meaning

The determination of drying time of paint film and putty film is of great significance in Coating construction and quality control:

Construction control: Knowing the drying time of Coating helps the construction unit to arrange a reasonable construction period and improve construction efficiency.

Film mass: The drying time is directly related to the mass of the film, and controlling the appropriate drying time can help avoid the problem of insufficient drying or excessive drying.

Product Development: By measuring the drying time, Coatings Manufacturers can optimize product formulations to ensure stable and consistent film performance.

5. Conclusion

The drying time measurement method of paint film and putty film is an important part of Coating construction and quality control. Through suitable operation methods and equipment, the drying time information can be accurately obtained, so as to ensure the Coating construction mass, improve construction efficiency, and ensure film performance. This is of great significance for Coating production and application.