The advent of innovative inks and varnishes has produced imaginative metal packaging

San Bernardo water has been sold in glass bottles for nearly a century. But with the advent of innovative inks and varnishes, tin cans have become more and more cool, and have opened up a world of creation for can designers, providing a variety of effects, resulting in imaginative metal packaging.

From reactive pigments to varnishes that can create tactile and embossed effects, engineers use technology to help brands make their products stand out on supermarket shelves.

In a magazine last month, the designers behind some of the world's most eye-catching packaging art talked about their projects, many of which were awarded in the early "Can of the Year" competition. They believe that the key to success is the use of highly engineered inks, varnishes and body shaping techniques, which provide them with a wide range of media and substrates.

In the list of contributing factors, tin can manufacturers have been using shocking ink types. Perhaps the most noticeable are photochromic, thermochromic and dark luminescent inks.

Although some of these inks have been around for decades, until recently, their cost prevented them from being used for purposes other than short-term printing. Since then, the efficiency of its production and canning process has been improved, thereby reducing costs. Now, all the major can makers offer a variety of designs that can utilize ink in different ways.

Each creative ink provides a unique design opportunity for the brand, and the secret of its success lies in its unique performance.

Thermochromic ink

One of the most striking is the ink that responds to temperature. Since the 1970s, canners have deployed in a variety of products, including T-shirts that change color when worn, but canners have released many color-changing design options.

One of them is Ball's "Spaceman" can, which is a concept to showcase its Thermochromic Reveal product. There are two main products that can achieve this effect: thermochromic liquid crystal (TLC) and bright dyes.

Thermochromic ink In TLC, this crystal has two properties, and they combine to produce color. First, they are always moving, transforming into new arrangements according to temperature. Second, they reflect light with an intensity that depends on the density of their arrangement. In the human eye, this fluctuation in reflectance is manifested in different colors.

At low temperatures, these crystals condense into a near-solid state, which prevents them from reflecting enough light, which means they show a darker color.

Their sensitivity to light allows them to be used to accurately indicate temperature changes within the substrate on which they are laid. This is especially useful in some medical devices, including thermometers. However, their shortcomings make them generally too expensive to be widely used in cans: they lose the ability to change with repeated use, application is difficult, and manufacturing costs are high.

On the other hand, bright dyes are more durable, cheaper, and easier to handle, but they are less sensitive to light.

Essentially, they are an ink containing organic acids and solvent pigments. At lower temperatures, they combine to show the color of pigments. However, at higher temperatures, their chemical attachment becomes unstable, they will separate, allowing light to penetrate them without showing any color.

This is useful when the bright dye is overlaid on a stable ink of a different color: at a lower temperature, the pigment of the bright dye is visible, but when the temperature rises, the color of the underlying ink is revealed .

Photochromic ink

When ultraviolet rays are irradiated on the photochromic ink, their molecular structure changes and becomes active. In their latent state, they allow light to pass through them. But in their active state, less light can penetrate. When these molecules are colored, their activation state appears as color.

The can maker has created six collection-worthy designs, making each can full of vitality in a series of colors. Because the beer consumption in summer is four times that in summer, and the summer in Canada is very short, designers are required to install the largest possible punching machine on the aluminum surface.

Luminous ink

Pigments that glow in the dark are nothing new-bioluminescent compounds have helped some fishes survive in the dark deep ocean for hundreds of millions of years. They also have a long history in industrial applications-for example, phosphorescent paint is used to highlight the numbers on watches.

For designers, this adds novel appeal to canned food. A marketing and strategic planner once said that canners’ luminous products are targeted at alcoholic beverage brands, which are more likely to sell their products in dark bars and nightclubs.

The Coca-Cola Company used luminous technology on aluminum bottles as early as 2006. Recently, PepsiCo used it to promote jelly soda in the Middle East with cans produced by Crown. The designers use ink produced by INX, which gives the can a super green appearance when it shines under ultraviolet light.

However, the effect of fluorescent ink is short-lived. They are not resistant to dyeing and will fade over time under strong light and sunlight. They can also reduce the sharpness of printed designs, so they can only be really used for low-resolution images.

Varnish

Designers have also been researching innovative varnishes that provide other special effects.

Coating giant PPG's iSense varnish range includes: reflective pigmentation that can produce a sparkling appearance, flexible varnishes for necked bottles and shaped cans, and varnishes that can produce matte and satin finishes.

Canpack uses this paint in the design of Asahe's Plzensky Prazdroi Slovensko beer brand. The varnish is applied strategically to specific parts of the can, highlighting special elements and giving the product a tactile dimension.

PPG also provides similar effects in personal care products. The company also produces primers with more than 1,000 color combinations.

In the next 5 to 10 years, the continuous development of domestic inks and varnishes will provide new packaging solutions for future can manufacturers, and the main push for continuous development of metal packaging companies.