Gold powder meets water-based dispersants: a leap in performance
The application of water-based dispersants in gold powder is mainly reflected in improving dispersibility, stability and
glossiness, and can also optimize the performance of gold powder in coatings, inks and other systems.
1. Application principle of water-based dispersants in gold powder
Dispersion and stabilization
Water-based dispersants reduce the interaction between particles to evenly disperse gold powder particles in aqueous
media to prevent agglomeration and sedimentation. Its mechanism of action includes:
Ionic action: forming a double electric layer through ion adsorption, generating electrostatic repulsion, and stabilizing
particle suspension.
Steric hindrance effect: dispersant molecules adsorbed on the surface of particles form a spatial barrier to prevent particles
from approaching.
Wetting and modification
Dispersants can change the surface properties of gold powder particles, improve their wettability in aqueous media, and
promote particle dispersion. For example, some dispersants can reduce the surface tension of aqueous media, making gold
powder easier to wet.
2. Specific application of water-based dispersants in gold powder
Coating system
Improve gloss: By optimizing the dispersibility of gold powder particles, reduce light scattering, and improve the specular
reflection effect of the coating.
Enhance hiding power: Evenly dispersed gold powder particles can cover the surface of the substrate more effectively and
improve hiding performance.
Improve leveling: Reduce system viscosity, reduce coating surface defects, and make the coating smoother.
Ink system
Improve coloring power: Well-dispersed gold powder particles can be more evenly distributed in the ink to enhance color
expression.
Prevent floating color: Stabilize the suspension state of gold powder particles to avoid uneven color of ink during drying.
Other applications
Water-based gold ink preparation: When preparing water-based gold ink, adding a special dispersant can prevent gold
powder flakes from agglomerating, ensuring the stability of the ink and printing effect.
Storage stability: Water-based dispersants can provide strong charge repulsion, so that the dispersion system has better
storage stability and prevents gold powder from flocculating, depositing and agglomerating again.
3. Optimization strategy of water-based dispersants in gold powder application
Dispersant selection
Select the appropriate type of dispersant according to the particle size, surface properties of the gold powder, pH value, polarity,
etc. of the target system (such as coatings and inks). For example, polyacrylate dispersants are suitable for most water-based
systems, while fatty alcohol polyoxyethylene ether sulfate dispersants are more suitable for occasions where surface tension
needs to be reduced.
Dosage optimization
Determine the optimal dosage of the dispersant through experiments. For example, when the protective agent/Au (weight ratio)
is 1.37, the gold powder particle size can reach a minimum of 10nm; when the ratio is higher than 1.8:1, precipitation may occur.
Therefore, the amount of dispersant needs to be adjusted according to the specific system to achieve the best dispersion effect.
Synergistic effect
The use of water-based dispersants in combination with other additives (such as wetting agents and leveling agents) can further
improve the dispersibility and application performance of gold powder. For example, the use of non-ionic wetting agents in
combination with water-based dispersants can achieve the best wetting and dispersion effect.
4. Precautions for water-based dispersants in gold powder applications
Compatibility of dispersants and gold powder
It is necessary to ensure that the selected dispersant has good compatibility with the gold powder and the target system to avoid problems
such as stratification, precipitation or performance degradation.
Effect of dispersant on system performance
The addition of dispersant may affect the viscosity, drying speed and other properties of the system, which need to be evaluated and adjusted
through experiments.
Storage and transportation
Gold powder products containing water-based dispersants should be stored in a dry and cool environment to avoid long-term exposure to
air to cause oxidation or performance changes.
