Application of Polyethylene Wax Emulsion in Ink

Compared with high-molecular-weight polyethylene, the low-molecular-weight polyethylene has similar softening point and other indicators, but the melt viscosity decreases greatly. Has waxy properties, commonly known as polyethylene wax. Polyethylene waxes are often classified into high-density polyethylene waxes and low-density polyethylene waxes according to density, or classified into cracking and synthesis methods according to the production process. Its use performance and processing performance are quite different. Polyethylene wax has stable chemical properties, smooth feel, good abrasion resistance and high hardness. Different methods of joining can impart different gloss changes to the system. Therefore, as a dispersant, anti-wear agent, brightener, matting agent, slip agent, etc., are widely used in inks, coatings and other industries. The addition of polyethylene wax in ink is generally done in the following ways:

1. Dispersed in organic solution to make wax, which is applied in the solvent system.

2. Dispersed in a water system to make a wax dispersion or wax emulsion for use in aqueous systems.

3, made of a suitable particle size of the micro-powder, directly added to the ink for use. In recent years, as environmental protection requirements have penetrated into every corner of society, water-based ink has developed rapidly. As an important additive for aqueous inks, the performance requirements for wax emulsions are also increasing. Due to its high softening point, non-polarity and emulsifying properties, combined with the requirements for wax particle size and emulsifier usage in the ink and coating industry, high melting point (wax melting point higher than 120 degrees) and ultra-fine particles The development of polyethylene wax emulsions with diameters (≤100 nm) has always been a technical difficulty in the domestic ink and coating industry. However, large foreign companies have large leading advantages in both production technology and application technology. BASF, Mike Gate, Klein and other industry giants use their brand and technology advantages to promote their wax and milk products in China, forming a pattern of foreign big companies' brands in the ink varnish market. Longkou Huarui New Material Technology Co., Ltd., with the support of Beijing University of Chemical Technology, has successfully developed AF series synthetic wax microemulsion series products, and carried out a large number of promotion work in the ink and coating field. Here, we report on the above work. The development of wax emulsions is discussed.

First, the characteristics of wax commonly used in the ink industry and its joining methods:

Second, AF series of polyethylene wax emulsion in water-based ink application characteristics: 1, slip, abrasion resistance, scratch resistance: After the wax emulsion added to the ink, the wax drifted to the surface of the coating film during the film formation process Dispersion, so that the coating has the protection of wax on the top layer, showing the characteristics of wax, due to its role in controlling the friction coefficient, the coating slip, abrasion resistance, scratch resistance have an impact. Since the AF series uses a very high hardness wax, the coating shows excellent wear resistance and smoothness. At the same time, due to the reduction of the friction coefficient, the direction of the applied force of the coating can be changed, thereby improving the scratch resistance of the coating.

2, the impact of emulsion particle size on the gloss of the coating: From the gloss point of view, the visible light wavelength is 400-700nm. When the polyethylene wax particles are less than half the wavelength of light, ie, ≤200 nm, diffraction of light is caused to bypass the particles to increase (at least not reduce) the coating gloss. It is generally believed that as the particle size of the wax particles changes, the effect of improving the gloss is more pronounced, and the effect on the coefficient of friction does not change much. At the same time, the gloss and the crystallinity of the wax are also greater. AF Series Wax Emulsion breaks through the difficulty of emulsification technology. The particle size of wax particles has reached nanometer level and is the best surface protection agent for high gloss aqueous systems.

3. Screening of the emulsification system to ensure the impact of water resistance and system compatibility. Taking into account the downstream customer's process requirements, defoamers, leveling agents and other additives are selected internationally renowned brand products and are suitable for the demanding requirements of high performance ink systems. Conclusion: Through hard work, domestic wax milk has been equivalent to imported brand-name products in terms of basic performance, and it also shows obvious cost-performance advantages. At present, it is a good opportunity for the rapid development of the ink-and-wash industry. We will do our best to improve product quality and output to meet market demands and make unremitting efforts to create fine ethnic chemical industry products.


Source: (Yang Weining, Huarui New Material Technology Company, Longkou City University of Chemical Technology)