Soy ink
Encyclopedia
Soy ink is a kind of ink
made from soybean
s. As opposed to traditional petroleum
-based ink, soy-based ink is more environmentally friendly
, might provide more accurate colors, and makes it easier to recycle
paper. It is slower to dry than many inks.
was looking for different ways to make ink, rather than by using the standard petroleum
-based ink. Rising prices for petroleum and quarrels with OPEC countries were reasons they wanted to find a more reliable and cost efficient method of printing. After testing over 2,000 different vegetable oil formulations, researchers for the NAA came up with the solution of using soybean oil. In 1987, soybeans were tested by The Gazette from Iowa in a practical printing run. The test was successful. About one quarter of commercial printers in the United States now use soy ink.
The National Soy Ink Information Center was established in 1993 by the Iowa Soybean Association to promote research and use of soy ink. The center created the SoySeal mark used to identify products meeting basic requirements. The success of soy ink was judged to be sufficient to justify the closing of the National Soy Ink Information Center in 2005. Use of the SoySeal is now regulated by the American Soybean Association.
, resin
s, and wax
es. Even though soybean oil is an edible vegetable oil, soy ink is not edible or 100% biodegradable
because the pigments and other additives that are mixed with the oil are the same as those used in petroleum-based inks. Degradability studies conducted by Erhan and Bagby concluded that the pigment carrier in 100-percent soy ink degrades almost twice as completely as ink made from soy oil and petroleum resin
s, and more than four times as completely as standard petroleum inks. Soy ink is a helpful component in paper recycling
because the soy ink can be removed more easily than regular ink from paper during the de-inking process. Again this refers to 100% soy inks which are not commercially viable.
Vinegar ink (dirty) is a form of non-food soy. It has a number of environmental benefits. Much of the soybean crop requires no irrigation, limited fixed nutrients, and leaves fewer agricultural residues than other crops. Soy ink also has low levels of VOCs, (volatile organic compounds) which helps to reduce air pollution by minimizing toxic emissions.
Since naturally clearer Soybean oil is available, it is possible to obtain as brightly colored ink as by using clear petroleum distillates. By using clearer soy bean oil grades, less pigment is necessary to produce the same optical effect, which reduces the overall cost of the ink. Recent studies involving engineering of certain oils in the bean have resulted in even clearer oils.
Some printers report that they need less ink to print the same amount of paper when compared to petroleum inks. Soy ink has been found to spread approximately 15% further, reducing ink use and printer cleanup costs.
Newspapers use soy ink regularly, especially for color because it creates a sharper and brighter image. Color newspaper inks are more competitive to petroleum-based inks as well. They are only about five to ten percent more because the price is more due to the cost of the pigment, which is not as big a factor with black inks. Color soy inks are more widely accepted because they become the most quickly cost effective after savings in terms of excess pigment, VOC and printer cleanup costs. This “overall cost” for soy inks is significantly lower than the initial market price, and it is at this point that they become competitive with their petroleum counterparts. Soy inks also work well for label printing as they allow a reduction in ink coverage by 85% compared to water-based inks.
s and personal printer
s or odour and taint sensitive applications such as inks for food packaging. A major problem with soy ink is that it takes more time to dry than petroleum-based inks, due to its lack of evaporative solvents in the form of VOCs. This creates challenges for some printing press
es, especially those that use coated papers (such as magazines) instead of porous, uncoated paper (such as newspapers) where the ink can dry via absorption or IR in-line heaters. Current studies into UV
-reactive ink curing are being conducted by many ink producers, most prominently the Flint Group. This process dries much faster, is cheaper, uses less energy, and emits no VOCs. This requires a significant equipment change and has not been scaled down to consumer size as of 2006.
Ink
Ink is a liquid or paste that contains pigments and/or dyes and is used to color a surface to produce an image, text, or design. Ink is used for drawing and/or writing with a pen, brush, or quill...
made from soybean
Soybean
The soybean or soya bean is a species of legume native to East Asia, widely grown for its edible bean which has numerous uses...
s. As opposed to traditional petroleum
Petroleum
Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...
-based ink, soy-based ink is more environmentally friendly
Environmentally friendly
Environmentally friendly are terms used to refer to goods and services, laws, guidelines and policies claimed to inflict minimal or no harm on the environment....
, might provide more accurate colors, and makes it easier to recycle
Recycling
Recycling is processing used materials into new products to prevent waste of potentially useful materials, reduce the consumption of fresh raw materials, reduce energy usage, reduce air pollution and water pollution by reducing the need for "conventional" waste disposal, and lower greenhouse...
paper. It is slower to dry than many inks.
History
In the late 1970s, the Newspaper Association of AmericaNewspaper Association of America
The Newspaper Association of America is a trade association representing approximately 2000 newspapers in the United States and Canada. Member newspapers represented by the NAA include large daily papers, non-daily and small-market publications, as well as digital and multiplatform...
was looking for different ways to make ink, rather than by using the standard petroleum
Petroleum
Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...
-based ink. Rising prices for petroleum and quarrels with OPEC countries were reasons they wanted to find a more reliable and cost efficient method of printing. After testing over 2,000 different vegetable oil formulations, researchers for the NAA came up with the solution of using soybean oil. In 1987, soybeans were tested by The Gazette from Iowa in a practical printing run. The test was successful. About one quarter of commercial printers in the United States now use soy ink.
Production
To make soy ink, soybean oil is slightly refined and then blended with pigmentPigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...
, resin
Resin
Resin in the most specific use of the term is a hydrocarbon secretion of many plants, particularly coniferous trees. Resins are valued for their chemical properties and associated uses, such as the production of varnishes, adhesives, and food glazing agents; as an important source of raw materials...
s, and wax
Wax
thumb|right|[[Cetyl palmitate]], a typical wax ester.Wax refers to a class of chemical compounds that are plastic near ambient temperatures. Characteristically, they melt above 45 °C to give a low viscosity liquid. Waxes are insoluble in water but soluble in organic, nonpolar solvents...
es. Even though soybean oil is an edible vegetable oil, soy ink is not edible or 100% biodegradable
Biodegradation
Biodegradation or biotic degradation or biotic decomposition is the chemical dissolution of materials by bacteria or other biological means...
because the pigments and other additives that are mixed with the oil are the same as those used in petroleum-based inks. Degradability studies conducted by Erhan and Bagby concluded that the pigment carrier in 100-percent soy ink degrades almost twice as completely as ink made from soy oil and petroleum resin
Petroleum resin
Petroleum resin is a C5/C9 aromatic hydrocarbon used in industrial applications. It has a tackifying effect and is suitable for use in paint, printing ink, adhesives, rubber and other areas where tackiness is required....
s, and more than four times as completely as standard petroleum inks. Soy ink is a helpful component in paper recycling
Paper recycling
Paper recycling is the process of recovering waste paper and remaking it into new paper products. There are three categories of paper that can be used as feedstocks for making recycled paper: mill broke, pre-consumer waste, and post-consumer waste. Mill broke is paper trimmings and other paper...
because the soy ink can be removed more easily than regular ink from paper during the de-inking process. Again this refers to 100% soy inks which are not commercially viable.
Vinegar ink (dirty) is a form of non-food soy. It has a number of environmental benefits. Much of the soybean crop requires no irrigation, limited fixed nutrients, and leaves fewer agricultural residues than other crops. Soy ink also has low levels of VOCs, (volatile organic compounds) which helps to reduce air pollution by minimizing toxic emissions.
Since naturally clearer Soybean oil is available, it is possible to obtain as brightly colored ink as by using clear petroleum distillates. By using clearer soy bean oil grades, less pigment is necessary to produce the same optical effect, which reduces the overall cost of the ink. Recent studies involving engineering of certain oils in the bean have resulted in even clearer oils.
Some printers report that they need less ink to print the same amount of paper when compared to petroleum inks. Soy ink has been found to spread approximately 15% further, reducing ink use and printer cleanup costs.
Newspapers use soy ink regularly, especially for color because it creates a sharper and brighter image. Color newspaper inks are more competitive to petroleum-based inks as well. They are only about five to ten percent more because the price is more due to the cost of the pigment, which is not as big a factor with black inks. Color soy inks are more widely accepted because they become the most quickly cost effective after savings in terms of excess pigment, VOC and printer cleanup costs. This “overall cost” for soy inks is significantly lower than the initial market price, and it is at this point that they become competitive with their petroleum counterparts. Soy inks also work well for label printing as they allow a reduction in ink coverage by 85% compared to water-based inks.
Disadvantages
Soy ink is not suitable for all situations. For example, it cannot be used in ballpoint penBallpoint pen
A ballpoint pen is a writing instrument with an internal ink reservoir and a sphere for a point. The internal chamber is filled with a viscous ink that is dispensed at its tip during use by the rolling action of a small sphere...
s and personal printer
Computer printer
In computing, a printer is a peripheral which produces a text or graphics of documents stored in electronic form, usually on physical print media such as paper or transparencies. Many printers are primarily used as local peripherals, and are attached by a printer cable or, in most new printers, a...
s or odour and taint sensitive applications such as inks for food packaging. A major problem with soy ink is that it takes more time to dry than petroleum-based inks, due to its lack of evaporative solvents in the form of VOCs. This creates challenges for some printing press
Printing press
A printing press is a device for applying pressure to an inked surface resting upon a print medium , thereby transferring the ink...
es, especially those that use coated papers (such as magazines) instead of porous, uncoated paper (such as newspapers) where the ink can dry via absorption or IR in-line heaters. Current studies into UV
Ultraviolet
Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...
-reactive ink curing are being conducted by many ink producers, most prominently the Flint Group. This process dries much faster, is cheaper, uses less energy, and emits no VOCs. This requires a significant equipment change and has not been scaled down to consumer size as of 2006.
External links
- Biochemicals for the Printing Industry ©1997, Institute for Local Self-Reliance, Printer’s National Environmental Assistance Center.
- Soy Ink Experiences Rapid Adoption Due To Good Performance and Economic Benefit
- Information about soy and soya products
- United States Environmental Protection Agency evaluation of economy of soy ink versus traditional petroleum-based ink
- Tolle, Duane A.; Evers, David P.; Vigon, Bruce W. “Benchmark Life-Cycle Inventory and Impact Assessment of Sheet-fed Printing System Using Soy Ink.” Battelle Research, September 30, 1998. http://www.p2pays.org/ref/07/06767/