In the late 1970s, rising prices for petroleum and tensions with the Organization of Petroleum Exporting Countries (OPEC) were the impetus to find a more reliable and cost efficient method of printing. The Newspaper Association of America (NAA) was looking for different ways to make ink, rather than using petroleum-based products. In 1987, the Gazette from Iowa successfully tested a soy-based printing ink in a commercial application, after over 2000 different vegetable oil formulations had been evaluated.
The Iowa Soybean Association established the National Soy Ink Information Center in 1993 to promote research and use of soy ink. Soy ink became so successful that the Center closed in 2005.
In the Farm Security and Rural Investment Act of 2002, the United States Secretary of Agriculture coined the term “bio-based.” Commercial or industrial products (other than human food or animal feed) in this category are composed, in whole or in significant part, of biological products or renewable domestic agricultural (including plant, animal, and marine materials) or forestry materials, or an intermediate feedstock.1
Since that time, the Biobased Manufacturer’s Association has defined bio-based materials as those that contain plant or animal materials as the main ingredient, and they are used as a renewable resource.
As an aside, although linseed oil had been the primary plant-based resin for alkyd paints for years, the Volatile Organic Compound (VOC) regulations encouraged resin manufacturers to consider other sources, such as soy, safflower, sunflower and others, building on the fact that all contain various types and concentrations of fatty acids, and therefore differ in unsaturation and the ability to cross-link and react with other moieties.
Fatty acid composition of some common edible fats and oils.2
In addition to the benefit of not being tied to petroleum prices, biobased materials’ chemistries can be more easily tailored for particular end uses. Bio-based materials are less harmful to the environment and do not impact air quality as do petrol-based products. The plant-based products tend to be lighter in color, which allows for brighter, cleaner colors and lower use of pigments and dyes to achieve similar colors using petroleum-based vehicles. This also contributes to lower system costs in most cases.
However, consistent across other coating, adhesive and paint formulations, bio-based raw materials for inks aren't necessarily going to meet every criteria for an “improved” ink system, meaning better for the environment (lower VOC’s), better for the customer (lower cost and/or better performance and ease of application) and usually recyclable.
The following are some of the bio-based chemistries available for inks.
Raw materials for bio-based inks and other coatings are highlighted at every trade show, and an increasing number of suppliers are developing new products for existing and new applications. Bio-based inks are used for printing on paperboard and carton/cardboard as well as non-porous substrates such as plastic wraps and bags. Due to relatively slow-drying with bio-based adhesives, suppliers have developed energy-curable resins (UV) that cure relatively instantly.
The United States Department of Agriculture maintains a website of “biopreferred” materials for many applications. USDA's BioPreferred® Program catalog assists users in identifying products that qualify for mandatory federal purchasing, are certified through the voluntary labeling initiative, or both.
The goal of the BioPreferred program is to increase the purchase and use of bio-based products, spur economic development, create new jobs and provide new markets for farm commodities. The increased development, purchase, and use of bio-based products reduces U.S. reliance on petroleum, increases the use of renewable agricultural resources, and contributes to reducing adverse environmental and health impacts.4
Companies with bio-based products voluntarily submit their product information for inclusion in this Catalog. Although you cannot purchase a product directly from the Catalog, sourcing information, such as product details and company websites, is provided.
Below are some helpful online resources for more information on bio-based raw materials and ink formulations.3
- BioPreferred.gov Catalog
- Green Environment News: Biobased Manufacturers Association profile page
- European Commission: Regulation on Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH)
- National Association of Printing Ink Manufacturers (NAPIM) Biorenewable Content (BRC) program
- American Soybean Association Soy Ink Seal
- Printers’ National Environment Assistance Center: Printing Inks Fact Sheet
- Vertec BioSolvents
- Smithers Pira
- Lorama Group
In summary, with the technology development occurring as quickly as it is, formulators desiring to develop bio-based inks should review emergent literature and contact their raw material suppliers for recommendations.
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