Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page 30 Page 31 Page 32 Page 33 Page 34 Page 35 Page 36 Page 37 Page 38 Page 39 Page 40Inks From a sustainability standpoint, there are several factors to consider when researching ink options. They include the effect of the printing process on the environment and the recyclability of the finished printed piece. The issues of volatile organic compounds (VOCs) that are emit- ted during the printing process, use of non-renewable resources and renewable resource content are important subjects to address. Designers may want to discuss ink options with their printer keeping these factors in mind. Cost is, of course, another important factor; any opportunity to reduce ink usage also saves money. voc content | All inks contain some level of VOCs—even UV inks contain a minute amount. The higher the petroleum oil content in the ink, the higher the VOC levels. Historically, there was no real distinction between petroleum-based and vegetable oil or agricultural-based inks. The emergence of “vegetable oil based inks” is due to the replacement of all or part of a single component of the ink, which is the ink oil. It is important to understand the role of the ink oil as it is a solvent that keeps the pigments, resins, drying oils and other additives in solution. Conventional petroleum-based inks have always contained renewable vegetable oils such as soy, linseed, cottonseed, tung or china wood oil and in most cases “vegetable based” inks contain some level of petroleum oil (the vegetable content may vary, typically from 7% to 100% with the remainder being petroleum).10 The lower the amount of petroleum in the ink the better it is for the environment—fewer VOCs are emitted into the atmosphere and there is lower consumption of nonrenewable resources. voc emissions | For lithographic inks, there is a distinct difference between VOC content and VOC emissions. Due to the nature of the petroleum ink oil used in inks, very little of the ink oil actually evapo- rates. For sheet fed and non-heatset web inks, the EPA recognizes that only 5% of the VOC in the ink is released to the atmosphere. For heatset web inks, 80% of the VOCs are evaporated in the dryer and are cap- tured (with most of them being destroyed by an oxidizer). Since heatset inks dry by evaporation, the amount of vegetable oil that can be used is very low (5% – 7%) because the vegetable oils do not evaporate. 19 | Inks Consider using fewer ink colors, perhaps two instead of four. Four-color printing involves four metal printing plates and four separate inks. Attractive alternative designs can be made with effective use of spot colors. In addition, reduce full-page ink floods—more ink means more de-inking. De-inking is the process by which inks, adhesives, glues, staples and other non-paper elements are removed from recovered paper. De-inking raises some concern because the by product is waste sludge that must be disposed of. Less ink has less of an impact on the environment.