Making The Mark

Monday, September 18th, 2017

In the dynamic global market where competition is ever more intense, it is vital for packaging professionals to select suitable inks for different printing applications in order to achieve the best results. Getting quality print may not be as simple as it seems. By Lin Zhu, director of Ink Development, Videojet Technologies

A trusted partner can be the difference for ever-evolving industries in these rapidly progressing times. Forged on a foundation of communication, such relationships can yield mutually beneficial results for both business firm and client.

Take packaging professionals: aligning with the right coding and marking supplier can help navigate the crucial ink-selection process. With so many inks to choose from and so many factors to consider when using ink jet coding equipment, finding the right ink is of the utmost importance and could well save your company a lot of money.

The best ink suppliers study the evolution of packaging materials, understand the range of manufacturing environments, and proactively apply rigorous ink development processes to help ensure code performance and integrity. Those experts can create an ink that will meet your requirements, whatever they are.

Let’s take a quick look at some of the specialty inks on offer and their specific applications:

Food grade inks may be required on a package that comes in contact with food. Typically such inks are used for marking and coding on the inside of a package.

They are ideal for eggs, candy & confectionery, and certain incidental food-contact products such as flavoured sachets contained within a food package.

Fast dry inks have been designed to be used on fast moving production lines such as food packages using films and stretch/shrink wrap.

Retort and thermochronic inks are used to produce a change in colour which indicates that the food has passed through a critical retort process.

For example, when a product is cooked in its can, the colour of the code will change to another colour, helping indicate that the product has been cooked. This is ideal for soups, vegetables, sauces, meat in aluminium and tin-free steel cans, pouches, and retortable plastic containers.

Condensation resistant inks when applied directly after the cold-filling process adhere to beverage cans and bottles. These types of inks are durable during pasteurization and refrigeration/re-cooling.

Identify What You Need

Printing equipment suppliers focus heavily on new product design to provide the packaging industry with innovative, class leading coding solutions that support stringent production needs. However, research and development investment should not stop at the coding equipment.

The demand for new specialty inks, suited to an increasing variety of innovative packaging, is both a sign of real customer challenges and an indicator of where hardware suppliers should direct investment and expertise.

The material being coded influences ink performance. New high-performance plastics and can coatings are constantly being developed, and can present complex challenges to ink code adhesion.

The production environment also plays a significant role in how inks adhere. Factors like moisture, temperature, and humidity can all impact initial ink code adhesion and durability. Drying and curing times afforded by product processes and manufacturing environments must be accommodated.

Understanding these fixed ‘constraints’ is crucial to selecting an ink that can survive the manufacturing process environment. In preparation for discussing ink selection with printing equipment experts, you should ask yourself the following questions:

  • • What material am I coding onto?
  • • Are there any surface coatings or contaminants from the manufacturing process present on the product either before or after coding?
  • • What product surface colour variation exists, and what is my or my customer’s requirement for visual or machine readable code contrast?
  • • What is the printer operating environment and what temperature extremes will the product itself experience and the code need to endure?
  • • When and what components come into contact with the ink code after printing that may impact ink dry time and durability?

Let’s take the food manufacturing industry as an example. Meat and poultry producers face many printing challenges because of the low temperatures and the high humidity which are present in their processing facilities. The cold temperatures are necessary to help maintain optimum shelf life of fresh meat or frozen products, but it also creates havoc with the quality of coding.

Because of food safety regulations it is essential that the marking and coding of those products are clear, legible, and don’t become smudged. Using a specialty ink will help you achieve the best adhesion and durability in such environments.

Branding or coding may sometimes need to be applied directly onto a food product: for example, Sichuan Sundaily Village, one of China’s top five poultry and egg enterprises, which counts Walmart, Carrefour, and Kentucky Fried Chicken as its customers, approached a global coding and marking specialist to help them identify the right ink for their coding solution.

In China’s many street markets, eggs are sold by weight and packaged in clear plastic bags. This presents a challenge for companies which must rely on printing on the egg shells to brand and differentiate themselves from the competition.

The ink must be of the highest quality, crisp, clear and stand out from the rest. Coding on eggs is not without challenges, as the temperature and the humidity can make it difficult for the ink to adhere to the surface of the egg and because the porosity of the egg shell itself can vary depending on the hens and their diet, altering ink adherence and code quality.

A fast drying food grade ink was developed specifically to produce the most crisp and highly legible ink jet codes on egg shells which maintained its quality despite egg-egg shell surface variation.

The time between printing the code and its first contact with a material handling component, like a belt or mechanical guide, or another product may influence the code’s adhesion and legibility. These manufacturing process conditions can result in problems such as ink transfer or code smudging, and therefore should also be considered when selecting the required ink.

Access Experts

Manufacturers should take full advantage of the ink expertise offered by their marking and coding ink and equipment partner. There are multiple options and considerations to take into account when choosing ink, but by engaging hardware application specialists and ink chemists together, you can achieve a better fit to your exact needs.

An ink that worked yesterday might not work today due to a subtle change in a manufacturing process or an undisclosed change to the substrate by your supplier. An ink specialist and its unique set of tools can help diagnose these problems and recommend solutions that get code performance back to an optimal state.

Keeping Up With New Technology

Just as manufacturers are always improving their processes, ink specialists are constantly researching new formulations to meet new coding application challenges. Manufacturers need to take this into consideration as they upgrade or expand their systems. However, they should resist the temptation to cut corners.

Some packaging teams may move to save money by purchasing fluids from a third-party ink supplier. Since these fluids are engineered without taking into consideration the printer specifications, these fluids can degrade a printer’s performance and code appearance over time.

As a result, off-brand supplies can end up costing much more in the long run due to costs associated with excessive maintenance, premature part failures, and unpredictable downtime.

Packaging professionals will be well-served by partnering with a thorough coding and marking supplier in order to choose the proper ink for their applications. This relationship can be the critical difference in any business climate.