Research On Lithographic Ink Emulsification

Lithographic ink emulsification has been the key problem influencing printing quality and speed. The research of the interactive essentials of fountain solution and ink, and the relation of ink emulsification and printing quality was carried out. The main aims were to provide practical printing with theory and technique support, control effectively the problem of ink emulsification, decrease the ill influences from ink emulsification, and get quickly ink-water balance. The important of the research lied in that, combined wetting theory with practical printing product, the result can be used for improving printing quality to attain the high standard, enhancing printing speed, and reducing products cost. Meanwhile it can bring printing enterprises with great economic benefits and expedite printing industry.Using the principles of surface physics and chemistry, and emulsion theory and practice, and combining printability and printing technique theory, the research discussed the essentials of ink emulsion, analyzed the effects of ink emulsification on printing quality. Simultaneity, the research exploded the basic rules of ink emulsification, validated limitations of emulsification rate theory, and provided theory and technique supports for the control and solution of ink emulsification.The results indicated: emulsification rate theory was not good to explain the changing rules of the water-pickup of ink, especially when fountain solution's type, quantity, and concentration were changed, so there was certain limitation in emulsification rate theory; emulsion theory and practice was perfect to explain behaviors of ink emulsifying; when surface activity's concentration was not changed (normal number), solid density of printing product was descended when the water-pickup of ink was added; gloss was firstly increased with the water-pickup of ink, and attained to the maximum when the water-pickup of ink was about 20%, but then descended .