Printing inks: “More attention to EHS concerns”
Which technical trends do you see in the area of printing inks?
Eric Zhang: In publishing, vegetable oil is replacing mineral oil in lithographic and newsprint inks. We expect to see more non-VOC inks for lithography. For packaging applications, Asian companies that use solvent-borne inks seem to be moving away from aromatic and ketone solvents, replacing them with esters and alcohols. Chinese and Korean regulators have excluded aromatic and ketone solvents from packaging ink. It appears that the Indian market will do the same.
It’s worth noting that solvent-borne ink is becoming universal for substrates and packaging. Conventional solvent-borne ink is transitioning to lower-VOC inks, such as alcohol/water, water-borne, and UV/EB. UV/EB ink is growing fast, but its expansion may be limited by standards restricting the migration of substances in contact with food, the drive for universal application, and a need to lower costs.
In how far do current regulations affect the development of raw materials for printing inks?
Zhang: The regulatory landscape in Asia makes this region the most dynamic place in the world. Regulations in East Asia strongly impact the ink market because policymakers and consumers are paying more attention to EHS concerns. Some controls, such as the JPIMA Negative List and the Chinese GB9685 Standard, are as popular as REACH and FDA regulations. These efforts have improved packaging quality in the region. Aromatic- and ketone-soluble ink has been totally replaced by ester- and alcohol-soluble ink and raw materials.
To improve air quality, the Chinese government is drafting rules to lower VOC emissions from the printing industry. The Korean government has regulations restricting the use of ester solvents in inks. These actions will impact developments in raw materials for printing ink. In North America, Proposition 65 and EPA rules inhibit the use of many materials, which in turn restrict the use of raw materials that are compatible with the listed materials.
How important have bio-based raw materials become for printing ink additives?
Zhang: For printing ink additives, some bio-based materials have already been used, such as soybean oil for offset ink. Some bio-based raw materials, e.g. cellulose ester, can serve as the main binder or additive in ink. Some bio-based polyols are reportedly being used structural units for polymers. Moreover, in some developed countries, such as Japan, eco-friendly marks designed by various industrial groups are encouraging ink companies to use more bio-based raw materials during formulation development.
However, for now, the main ink components are not bio-based, e.g. organic pigments, polyurethane, and it will take considerable effort over the long haul to increase the bio-based material content of printing ink.