Two-dimensional ink making method (1)

For a long time, in the packaging printing ink manufacturing and packaging printing process, the addition and subtraction "technique stacking method" and the "intrinsic viscosity method" commonly used in ink formulation design (weigh a certain amount of polymer dissolved in different solubility In the solvent of the parameter, the intrinsic viscosity is measured at a certain temperature, and the maximum intrinsic viscosity obtained can be determined as the solubility parameter of the polymer equal to the solubility parameter value of the system) and the "equilibrium swelling method" (at a certain temperature The cross-linked polymer is swelled in a solvent having different solubility parameters. When equilibrium is reached, the swelling degree and the maximum swelling degree are determined. The solubility parameter of the corresponding solvent system is the polymer. The solubility parameters), which are currently relatively simple and intuitive methods for determining the solubility parameters of polymer compounds, are far from meeting the requirements of modern packaging and printing technology. 
The "two-dimensional ink making method" described in this article is based on the principle that the solubility parameters are the same or similar to each other, to determine whether the resin is dissolved in the solvent or mixed solvent and the mutual solubility of the ink and the substrate.
The second is to predict the mutual solubility of two solvents or inks and substrates based on the principle that the solubility parameters have the same or similar solubility.
The third is based on solubility parameters, can estimate the mutual solubility of two or more resins (its parameters can not be greater than 1.5) and substrate adhesion. 
The fourth method is to use the solubility of the resin in the packaging printing ink system in a series of solvents with known solubility parameters, and the range of solubility parameters of the resin and the substrate can be experimentally determined.
According to the solubility parameter, we can judge the solvent resistance of ink film after printing. 
The sixth is based on the ink system of the resin, dissolved hydrogen bond strength and softening point, can be estimated after printing ink film adhesion and flexibility and wear resistance, heat resistance. 
Based on the parameters of the dissolved hydrogen bonding force, it is possible to develop a suitable inexpensive resin and solvent in the process of printing and packaging the ink in order to control the material cost of the packaging printing ink. 
However, two or more resins or mixed solvents are often used in packaging printing ink products. The calculation method must control its hydrogen bond strength and surface tension and volatilization rate in order to accurately obtain the ideal (ie, no interaction) mixed solution viscosity, in order to achieve high quality and low cost ink products--solvent and resin solubility. Hydrogen bonding force between ink solution and substrate (abbreviated as dissolved hydrogen bonding force). 
Note: The mixed solvent will form a volatile gradient equilibrium due to the speed and compatibility, and the volatilization rate will be faster than any single solvent component. At the same time, a higher dissolved hydrogen bond force can be obtained during the ink ink film heating process, and the pinhole of the ink film can be prevented. , Shrinkage and whitening.
On the other hand, under the principle of solvation, the swelling and dissolution of its high polymer are related to the solvation/the contact between the high molecular weight polymer and the solvent, and the interaction between the solvent molecules and the polymer molecules. This force is greater than the cohesion between the polymer molecules, so the polymer molecules can be separated from each other and dissolved in the solvent. The polar solvent molecules and the polar groups of the polymer attract each other to generate solvation and dissolve the polymer. Everyone knows that this effect is often simply explained as follows: acidic solvents can dissolve alkaline polymers, otherwise it is the other way around. In theory, it is often explained that the electron acceptor can dissolve the electron donor.
The solvent is volatilized and dried from the ink film and is called the volatilization rate. Although it has been proposed that the boiling point of a solvent can be used as a basis for predicting its volatility, only this homologue or between petroleum solvents meets this rule. Therefore, the method still being used as a general method is no longer scientific. It is mainly inaccurate. One of the main reasons is the influence of hydrogen bonds, such as the boiling point of ethanol and benzene is close, and the volatilization rate of benzene is 2 times that of ethanol. Butanol has a lower boiling point than n-butyl acetate, and the volatilization rate is also low. Hydrogen bonding plays an important role in limiting the volatilization of the ink film of a solvent-based printing ink. 
Of course, temperature, humidity, surface area of ​​the ink film, the molecular weight of the polymer, and the size of the surface tension all directly affect the drying speed of the ink film of the packaging printing ink, especially the fastness of adhesion (curing) after the printing and compounding. (to be continued)