Wetting agents in inks: the secret weapon to improve printing quality

In the printing industry, the performance of ink directly determines the quality of printed products. Ink is composed of pigments, binders, fillers and additives, among which wetting agents, as an important additive, play an indispensable role in improving printing quality. This article will discuss in detail the working principle of wetting agents in inks and how they can improve printing quality.

1. Basic functions of wetting agents

Wetting agent, also known as wetting agent, is a surfactant whose core function is to reduce the surface tension of the liquid, increase the contact angle between the liquid and the object, and enable the liquid to be better distributed on the surface of the object. In the ink system, the main functions of the wetting agent include:

1). Improve ink fluidity:

Wetting agents can significantly reduce the viscosity of ink, making it easier to flow during the printing process and spread evenly.

2). Adjust ink viscosity: 

Wetting agent can adjust the viscosity of ink so that it remains stable during the printing process and is not easy to adhere to the printing equipment, thus ensuring a smooth printing process.

3）.Enhance ink wettability:

Wetting agents can improve the wettability between ink and substrate, making it easier for the ink to spread on the surface of the substrate to form a flat and smooth coating.

2. How wetting agents improve printing quality

1).Improve coating uniformity and adhesion

Wetting agents can selectively adsorb on the interface between ink and substrate, significantly changing the surface tension or interfacial energy, making it easier for the ink to spread on the substrate. This not only increases the uniformity of the coating, but also improves the adhesion between the ink and the substrate, thereby enhancing the durability of the print.

2). Optimize printing effect

During the printing process, the leveling and stability of the ink are crucial to obtaining good printing results. Wetting agents can optimize the leveling of ink, allowing the ink to spread evenly on the surface of the substrate, reducing defects such as blur and pinholes, and improving color vividness and clarity.

3).Enhance the water resistance of ink

During the printing process of water-based ink, due to the addition of plasticizers, resins and other substances, it is easy to cause poor wettability of the ink. The wetting agent can adjust the surface tension of the ink so that it is equal to or less than the surface tension of the printing surface, thereby enhancing the water resistance of the ink and improving the water and wear resistance of the printed matter.

4) Improve ink dispersion efficiency and stability

The pigments and binders in the ink need to be stably dispersed to ensure the color consistency and stability of the printed product. Wetting agents can reduce the interfacial tension between liquid and solid, enhance the lyophilicity of the pigment, thereby improving the dispersion efficiency and stability and reducing problems such as floating color and floating.