The liquid resistance of the paint film refers to the resistance of the paint film to the etching effect of the solution. This performance parameter can help evaluate the durability of the coating when subjected to liquid erosion. According to the national standard GB4893.1 "Determination of Liquid Resistance of Furniture Surface Paint Film", the measurement method of the liquid resistance of the paint film is as follows:
1. Equipment and materials:
Test solution: Use the corresponding test solution and choose according to the specific situation.
Equipment: glass cover, stainless steel pointed forceps, observation box, etc.
Material: qualitative filter paper, cleaning liquid, etc.
2. Test steps:
Wipe the paint film on the surface of the sample with a soft cloth or gauze.
Select three test areas and one comparison area on the specimen. Make sure that the center point of the test area is more than 40mm away from the edge of the specimen, and that the center distance between the two test areas is more than 65mm.
A qualitative filter paper with a diameter of 25 mm was immersed in the test solution, then removed using stainless steel pointed forceps, five layers of filter paper were placed on each test area, and the filter paper was covered with a glass cover.
During the test, it is necessary to keep the filter paper moist at all times. If the test time is long, the test solution in the filter paper may evaporate and cause it to no longer be wet. In this case, a dropper can be used to replenish the test solution on the filter paper to keep it moist.
At the end of the specified test time (usually according to the product standard or agreement), remove the glass cover and filter paper.
Use a clean filter paper to blot off the residue and let stand for 16 to 24 hours.
Wash the surface of the sample with water, then dry with a soft cloth and let stand for 30 minutes.
Observe whether there are differences between the test area and the comparison area, whether there are discoloration, bubbling, wrinkles, etc., and evaluate the liquid resistance of the paint film according to the grading standards. The rating criteria for film liquid resistance are as follows:
3. Classification standard:
Level 1: No Imprint
Level 2: Slight tarnish impressions
Level 3: Slight discoloration or noticeable tarnish impressions
Level 4: Visible discoloration, bubbling, wrinkles, etc
Through the liquid resistance test of the paint film, the resistance performance of the coating to different liquids can be evaluated, helping to ensure the performance and mass of the coating in the face of liquid erosion. This is of great significance for mass assurance in areas such as furniture surface painting.
