Study On Synthesis And Properties Of Self-Gelling Rosin Modified Phenolic Resin

Phenolic resin used as binder of printing ink , which was the resin of condensation using phenol and aldehyde type compound,showed good performance in dryness and gloss. However,the fluidity of printing ink was very poor if ink was prepared by phenolic resin in common way. Rosin had good fluidity using as printing ink,Such as high soften point of rosin modified resin,good oil tolerance. After it was prepared to ink and a great deal of mineral oil was introduced,the speed of penetrating and fixation was greatly quickened. So it obtained broad appliance. By way of mostly variety of printing ink–offset printing light ink,it,which was adapted to advanced offset printing equipment,must possess high speed,multicolor and rapid drying at one time. Self-gelling rosin modified phenolic resin was more the same with offset point ink than ordinary phenolic resin. It had good storage stability,what's more,it was capable of forming the desired stable gel varnish by simple dissolving in mineral oil without additional gel-forming agents. So the resin was called self-gelling rosin modified phenolic resin. It was extensively used in offset printing ink,and was very good as binder of ink. The preparation of offset printing inks could be substantially simplified if it was possible to use self-gelling rosin modified phenolic resin which had a good compatibility with mineral oil and was capable of forming the desired stable gel varnish by simple dissolving in mineral oil or vegetable oils or mixtures of such oils,without additional reaction with aluminum compounds. The configuration of gel couldn't be destroyed and kept performance of gel when it is cut in high speed. It had great significance to printing.In this paper,self-gelling rosin modified phenolic resin was synthesized in two-steps. The first step , material gave mostly priority to octylphenol and formaldehyde. In alkaline condition,the resol phenol was prepared. The ratio of octylphenol and formaldehyde in mol which had effect on viscidity of resin was studied. The amount of catalyst,reaction temperature and reaction time which had effect on condensation was also studied. At the same time,the molecular weight and distribution of product made in lab was compared with foreign sample by gel...