Show your colours: Sustainable inks and pigments for packaging printing

• Brand owners expect unique and high-quality packaging products, but are increasingly looking at sustainability in packaging printing.

• Printing processes and production conditions can be made more sustainable in many ways - but how can this be achieved with the printing inks themselves?

• Colours and pigments must not only be visually convincing, but must also be considered in terms of their impact on the recycling cycle. They must therefore not only protect packaged food, for example, but also the environment.

• Different inks, different recycling results: Overall, however, manufacturers are paying more attention to ensuring better recycling of their inks and associated packaging products.
   

 

When it comes to packaging and the topic of sustainability, the focus is usually on the materials used. But these are only one aspect of many: The inks and pigments used in packaging printing also play a major role. Because these have to meet strict specifications, especially in the food sector - and at the same time can be composed more sustainably. 

This is what modern packaging printing must achieve

Brand manufacturers are quite demanding when it comes to their requirements for packaging printing. This applies to the quality of the printed products just as much as to sufficient flexibility to be able to fulfil special wishes. And of course the sustainability factor is also increasingly important.

Printing solutions for every need

• Flexible offers: Companies that have packaging printed in large runs usually rely on the Gravure printing. However, when it comes to smaller print runs with individualised imprints, digital printing remains the first choice.

• Elegant look, pleasant feel: Bright colours, metallic elements or partial (matt) varnishing - when it comes to appearance, brand manufacturers have clear ideas and use every printing and finishing technique that can create a unique look. Especially as this can also create a pleasant feel. 
   

Making packaging printing more sustainable – but how?

When it comes to sustainability, the principle of "reduction" predominates among brand manufacturers. For example through minimalist packaging designs that make do with fewer colours. The focus is also on more auf sustainable materials and printing processes.

In fact, changes and savings are possible all around the printing process. More efficient equipment with short set-up times, better filters for chemicals or better regeneration for developer solutions help to save resources at many points in production.

Nevertheless, the most important working material in the printing industry – ink. remains a central factor in sustainability. In sensitive areas (such as contact with foods), ink has to meet the highest standards of health safety anyway. But does that automatically make it harmless to the environment?

Better safe than sorry: printing inks and pigments in sensitive areas

A sensitive area where printing inks and pigments are used is food packaging. Especially when the ink comes into direct contact with the food. Packaging for food must therefore be produced according to clear legal requirements. They should:
 

• not release any ingredients or constituents into the packaged food that pose a health risk to consumers;

• not cause an unacceptable change in the taste, smell, etc. of the food;

• only be produced in accordance with the requirements of good manufacturing practice (GMP).
   

That’s how printing inks and pigments can become more sustainable

More sustainable printing processes that use fewer resources, for example, are only one side of the coin. When it comes to opportunities for more sustainability in packaging printing, a central question must therefore be: How can printing inks and pigments contribute to this goal? There are various approaches to this.

Environmentally friendly inks – there’s more to it than that

When it comes to more environmentally friendly printing inks, it is not enough to look only at the finished product. Instead, a holistic view is needed that
 

• takes the entire product cycle from development to disposal as well as

• all related products (primer, sealing wax, overprint varnishes and washing materials) into account.
   

This is an extensive task because undesirable environmental impacts can occur at many points between ink production, the printing process and disposal. In other words, it cannot just be a question of all the components of printing ink being environmentally compatible and sustainable. Ideally, they also contribute to more sustainable processing – less energy consumption in drying, less chemical input in recycling and much more.

Renewable raw materials for offset inks

Offset printing inks account for around 40 per cent of European printing ink demand. Most of these inks now do not contain synthetic, mineral oil-based binders. Instead, vegetable oils and tree resins are increasingly being used in production.
 

As welcome as the return to renewable raw materials for printing inks is (they were already used in the early days of letterpress printing): Here, too, possible ecological consequences cannot be ruled out. Especially with regard to the agricultural cultivation methods of the required oil plants.

Fertilisers, pesticides and land consumption depress the positive eco-balance. Thus, the ecological advantage over crude oil products is shrinking.

Water-based printing inks for packaging

Another approach is to use water-based printing inks that do not contain solvents. In principle, this is already an advantage because it makes the ink more compatible for people and the environment, at least during manufacturing and production. For example, because only small amounts of volatile organic compounds escape during drying.

However, depending on the substrate, drying can require more energy than with solvent-based inks. This is especially the case on plastics or metals. In addition, water-based inks often still cause difficulties in the recycling process, especially in the recycling of paper and cardboard packaging.

 

This is primarily because the inks can only be insufficiently separated from the paper fibres – nd then literally leave their mark. The so-called “dirt specks” prevent the creation of high-quality recycling materials.

However, the better “de-inkability” of printing inks has been a criterion for recyclability for some years now, for example, according to the requirements for the European Eco-label for printed products. Therefore, many ink manufacturers are working on solutions that are more recyclable.

Compostable pigments