Glue coatings can use suitable surfactants to reduce surface tension. Therefore, it is of great significance to study the effect of additives on the surface tension of coatings for the coating properties of curtain coating.
Experimental equipment and methods
Curtain coating testing machine, produced by BMB in Switzerland, with a width of 300mm, as shown in Figure 2-1;
Infrared Moisture Analyzer
Viscometer, DV-2 Brookfield Engineering Labs, USA;
Surface Tensiometer
Ring tack Tester
Digital Display Adhesion/Peel Tester
Constant temperature tape retention test machine
Forced Air Drying Oven DHG9203C
Electric applicator KCC202 UK RK.
This experiment is mainly to use the coating experimental curtain forming device provided by BMB company to test the curtain forming conditions of coatings with different surface tensions, and use the mach-angle (Mach angle) method to test the dynamic surface tension
experimental design
By selecting surfactants provided by different manufacturers, configuring coatings with different surface tensions, and testing the minimum curtain flow rate to evaluate the curtain forming stability of glue coatings. During the experiment, the dynamic surface tension of the glue coating , and the relationship between the dynamic surface tension and the stability of the glue curtain was studied at the same time.
The samples added with surfactant were selected for experimental coating, and the influence of surfactant addition on the adhesive properties of glue coating was tested .
Discussion of results
Effect of addition of surfactants on the minimum curtain flow In the glue coating, two different surfactants are added, the addition amount is 0-2.0% , and the corresponding minimum curtain flow data obtained by the experiment is shown in Table 3-2 , and The minimum curtain flow rate and the amount of surfactant added were plotted and analyzed. It can be seen from Figure 3-2 that when the amount of surfactant changes from 0 to 0.5 %, it has almost no effect on the curtain formation, but when it increases from 0.5% to 1.3 %, the minimum flow rate of curtain formation changes significantly. % above, the change slows down.
For details, please read the paper " Study on the Performance of Self-adhesive Label Glue Curtain Coating Coatings" by Chen Youjun, a scholar of South CHINA University of Technology
