EFFECT OF PRINTING INK BINDER COMPOSITION ON EMULSIFICATION OF FOUNTAIN SOLUTIONS

This paper discusses the effect of alkyd resin composition on the emul sification of fountain solution into heat-set printing ink oil. Data o n interfacial tension and initial droplet size are reported. The initi al droplet size of emulsions formed by mixing fountain solution and pr inting ink oil, containing alkyd resin, is strongly dependent on conce ntration and type of alkyd resin. Addition of non-ionic surfactant to the aqueous solution decreased the fountain solution-oil interfacial t ension but had no significant effect on droplet size. Addition of isop ropyl alcohol to the aqueous phase resulted in successively smaller dr oplets. Higher concentrations of isopropyl alcohol gave smaller drople ts. The interfacial tension between water and alkyd resin-containing o il decreased with alkyd resin concentration and polarity. This suggest s that the alkyd resin orients itself at the interface with polar grou ps in the water and non polar segments in the oil. The alkyd resin the n acts as an emulsifier and stabilizes the emulsion.