Waterborne inks for flexography and gravure printing methods, are made from resins, pigments, solvents, waxes, surfactants, crosslinking agents and additives. Resin is the main principle for achieving the functional properties of the printing, in addition to the role of binder for dispersing pigment. A resin is a substance for spreading pigmentation and preventing its aggregation again. It also causes adhesion to substrate. Polymer dendritic network maintains gloss on porous substrates. Polymer crosslinked or oxidized structures create resistance to chemicals in contact with printed packaging. In addition, these materials provide resistance to wear, resistance to environmental conditions such as heat, melting and freezing, ozone, light, oxidizing agents, moisture and so on. Also, the viscosity of resin provides the rheological properties necessary to transfer the ink from the press to the substrate.
Emulsion constituents are prepared by emulsion polymerization in water in the presence of active surface stabilizers. Viscosity is not dependent on molecular weight and depends on the solid content and particle size distribution, so high molecular weights (above 200,000 g / mol) with low viscosity can be achieved.
Resinfam has produced two products with polyfam PR578C and PR579C to produce and waterbase inks and varnishes. The PR578C is a medium hardness acrylic emulsion polymer that is used as a preparation media for high-gloss flexography and glossy inks. In contrast, Polymer PR579C is a high hardness acrylic styrene emulsion polymer that is used in conjunction with PR578C to produce ink and varnish. These resins are compatible with most waterbase resins of styrene acrylic and acrylic emulsions. The films made with PE578C are glossy and water resistant. Moreover, adding PR579C polyamide improved solubility and cleansing properties as well as improved gloss.
Also for the specific use of printing on polyethylene surfaces, Resinfam has also produced another product with PR624 code. PR624 is a pure self-crosslinking acrylic emulsion polymer.
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