The role and selection of gravure ink solvent

In gravure printing inks, solvents have the effect of dissolving the resin, adjusting ink viscosity and ink drying speed, and improving the wettability of the surface of the substrate. The correct choice of solvent plays an extremely important role in improving the quality and economic benefits of printing products and preventing the occurrence of printing failures. In this paper, based on the common solvent used in the introduction of printing, a basic method for selecting solvents is proposed for the reference of gravure printing workers.
First, the types and nature of commonly used solvents In general, the solvents used in gravure printing inks are all organic compounds, there are many methods for the classification of solvents. According to the boiling point, generally can be divided into low boiling point (boiling less than 100), medium boiling point (boiling point in 100-150) and high boiling point (150-225). If divided by chemical structure, the solvent can be roughly divided into the following categories.
1. Aliphatic hydrocarbons: Generally small in odor, low in toxicity, cheap in price, but not very soluble. Such as: petroleum ether, gasoline ether, n-hexane, n-heptane and so on.
2. Aromatic hydrocarbons: There is a strong irritating odor. It is toxic, cost more expensive than you, and has better solubility than aliphatic hydrocarbons. Such as: toluene, xylene, naphthalene solvents (decalin, tetrahydronaphthalene) and so on.
3, alcohols: good odor, slightly toxic, slightly higher cost, better solubility for certain resins. Such as ethanol, isopropanol, n-butanol and so on. Solubility of alcohol solvents on the resin decreases with increasing water content.
Table 1 Main physicochemical parameters of commonly used solvents