Markem-Imaje has launched a new thermochromic ink, MS596, that can be used to print on both metal cans and plastic film, and is designed for retort sterilisation of packaged food containers including filled cans or plastic pouches.
The ink changes from black to blue when the food package reaches the correct temperature of between 115C and 125C.
Markem-Imaje says its MS596 thermochromic ink can work effectively in a wide range of environmental conditions, and says it comes with “excellent adhesion” to polyolefin pouches. No pre or post-treatment of the packaging material is required.
According to the company the new ink gives “good contrast” on the dedicated white printing area, and offers a clear colour change from black to blue at retort temperature. Markem-Imaje says unlike some earlier generations of thermochromic ink, today’s innovation will not change colour prematurely due to temperature effects from the printer itself, rather than the sterilisation process.
The ink has a drying time of one second on all materials. An issue with previous generations of thermochromic ink was smearing of the printed code, which could lead to the information becoming illegible. However, Markem-Imaje says MS596 resists smearing to maintain high coding legibility, and says it is less affected by oil and grease residues or water during the retort process.
All raw materials used to create the new ink have been chosen in line with the Swiss Ordinance, which helps ensure inks that can come into contact with food are safe to use.
The ink is formulated and manufactured in accordance with the EuPIA (European Printing Ink Association) ‘Guideline on printing inks applied to the non-food contact surface of food packaging materials and articles’, and complies fully with the EuPIA Exclusion Policy.
It does not feature ingredients dangerous to aquatic life, nor does it contain methanol, which is known to be toxic to the human nervous system. In fact no ink launched by Markem-Imaje within the last decade contains methanol. The company says this forms part of its long-standing approach to go beyond bare minimum compliance and consider where regulations are headed, so that its customers are not caught off guard by tightening legislation. The spate of methanol-related hand sanitiser scandals earlier this year suggests this ingredient is likely to face tighter regulations going forward.
Markem-Imaje is a member of the Australian Packaging & Processing Machinery Association (APPMA).