You can roughly determine the function of additives based on their names. However, finding the ideal additive for a particular paint that doesn’t cause side effects often relies on experience and intuition.
1. What Are Additives?
The primary components of paint are resin, pigment, and solvent. However, to ensure the smooth manufacturing, storage, application, and functionality of paint as a coating, relying solely on the functions of these three main components can be practically challenging. Therefore, it’s common to add small amounts of specific ingredients to achieve desired functions, and these ingredients are called additives. Often, they are named based on the specific function they serve.
2. Types of Paint Additives
While the main types of paint additives vary in terms of the stage at which their effects are manifested (manufacturing, storage, application, or coating), it’s important to note that these additives are typically added to paint during the manufacturing stage. Furthermore, one additive may have multiple names. For instance, additives that increase paint viscosity, especially at low shear rates, are known as thickeners, rheology modifiers, rheological control agents, thixotropy agents, or sedimentation inhibitors, depending on the context.
3. Selection and Use of Additives
Paint often requires different additives for different functions, leading to situations where a single paint may contain more than ten additives, or multiple additives are used for the same purpose. Since many additives have a significant effect in small quantities, precise measurement and careful addition are necessary, including pre-dilution with a solvent. While the general mechanisms of action for each additive are understood, selecting the optimal additive for a specific paint may require experience and trial-and-error. Additionally, it’s not uncommon to experience side effects even when achieving the desired effects. In fact, finding additives that produce the desired effects without side effects can be challenging. For example, an anti-foaming additive may work well but lead to film defects, or a pigment dispersant may improve dispersion but reduce the pot life of a two-component coating. With a wide variety of additive options available, it may be more practical to aim for achieving satisfactory results rather than finding the perfect additive.