EZHOU ANJEKA TECHNOLOGY CO.,Ltd Anjeka@anjeka.net 86-0711-5117111
Anjeka 6503
Project: Dispersant Comparison
Category: Testing of Dispersant Performance in Polyester Resin for Titanium Dioxide Dispersion and Let-Down Stability
Personnel: R&D Department
Date Submitted: Sep. 28, 2025
Abstract
This study evaluates the performance of selected Anjeka dispersants for dispersing titanium dioxide and carbon black in a polyester resin baking enamel system. The assessment is based on two key observations: the color difference in rub-up tests on drawn-down panels and the degree of pigment flooding in the paste stored in the container.A color paste was prepared by grinding polyester resin with titanium dioxide and carbon black. This paste was then let down into a paint, which was placed under observation. The paint formulated with Anjeka dispersant, after standing at 60°C for 3 days, exhibited a smaller color difference in rub-up tests compared to the reference sample.
Key words:dispersant, Rub-up Color Difference
1.Objective
To evaluate and select a dispersant with superior anti-flooding performance for titanium dioxide dispersion in a coil coating system, by conducting a comparative study against the competitive dispersant 2311.
2.Experimental Plan
The dispersants are to be incorporated into a polyester resin system to prepare color pastes. The state of these pastes will be observed after standing. Subsequently, the pastes will be let down into paints. Draw-down panels will be prepared and subjected to rub-up tests to evaluate color difference.
3.Results and Discussion
3.1 Procedure
According to Table 1 below, prepare separate white and black color pastes (using AJK 6503 and the competitor 2311 for the white pastes, and AJK 6040 for the black paste). Measure the viscosity after grinding is complete.
Prepare the gray paint according to Table 2. Perform a rub-up test on the draw-down panel and measure the color difference of the rubbed area using a colorimeter. Place the paste sample in a 60°C oven for 3 days for observation.
3.2 Performance Testing
3.2.1 Experimental Formulation
Table1 Black & White Monochrome Formulations
| White paste | Black paste | Remarks | |
| polyester resin | 30 | 60 | Wanbang 3871 |
| solvent | 8.5 | 27 | Xylene |
| dispersant | 1.5 | 3 |
6503/2311 6040 |
| titanium dioxide | 60 | Lomon R996 | |
| Carbon black | 10 | Mitsubishi MA100 | |
| Total | 100 | 100 |
Prepare the paste according to the formulation in Table 1. Add glass beads with a diameter of 3 mm at a 1.2:1 bead-to-paste mass ratio. Place the mixture in a shaker for dispersion and grind until the fineness is ≤ 5 μm.
Table 2. Formulation for Let-down of Black & White Monochrome Pastes
| Amount | Remarks | |
| Polyurethane Resin | 50 | 3871 |
| Amino Resin | 15 | 5717 |
| solvent | 13 | Xylene |
| White paste | 20 | |
| 6040 black past | 2 | |
| Total | 100 |
Mix the components uniformly according to Table 2 to prepare the gray paint.
3.2.3 Results and Discussion
Color Paste Comparison
| mpa.s(25℃) | White paste | |
| competitor 2311 | AJK6503 | |
| Viscosity | 1178 | 1226 |
| Fineness | ≤10 μm | ≤ 10 μm |
Anjeka dispersant 6503 shows viscosity reduction performance essentially equivalent to that of the reference dispersant 2311.
at 60°C for 3 days
Comparison of Rub-up Tests on Draw-down Panels:
| ∆E | Reference 2311 White Paste + AJK 6040 Black Paste | AJK 6503 White Paste + AJK 6040 Black Paste |
| Initial Rub-up Color Difference | 2 | 1.4 |
| Rub-up Color Difference After Heat Aging | 2.2 | 1.5 |
| Color Difference Before and After Heat Aging | 0.78 | 1.6 |
6503: Before/After Heat Aging 2311: Before/After Heat Aging
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Anjeka6503 exhibits a smaller rub-up color difference both before and after heat aging compared to the competitive product 2311.
Although reference sample 2311 shows a slightly smaller color difference before and after heat aging, severe flooding (whitening) was observed on the panel surface in both cases.
Anjeka Dispersant Reference: 2311
No delamination or flooding observed. Severe Flooding
4. Conclusions
Testing demonstrates that in the coil coating system, the white paste prepared with Anjikang dispersant Anjeka 6503 and the black paste prepared with Anjeka 6040 exhibit excellent viscosity reduction and outstanding stability against pigment flooding.