Digital printing technology, already prominent in industries like ceramic and packaging, has expanded into the coil coating industry in time but is generally limited to printing on individual sheets. Globus developed an innovative process to digitally print a strip in a continuous process, overcoming the limitations of traditional sheet-based printing.
Globus's innovation lies in the fact that the continuous process is inherently faster to operate, thus allowing for higher productivity rates, and allows the same flexibility of sheet-by-sheet printing, since different images can be printed on the coil without stopping the line.
The use of solvent-free inks underscores an environmental commitment, eliminating harmful emissions and achieving a zero-carbon footprint.
Printing on metal strips has traditionally been available by means of the classic gravure technology. This solution, however, has significant disadvantages in terms of equipment setup times and roll inventory requirements: the resulting process is therefore inefficient and offers little flexibility.
To overcome these limitations, Globus has developed a digital printing solution which, besides offering higher operational flexibility, is also vastly superior in terms of printing quality.
Globus Digital Printing Lines can print any image with a very large repeat interval (up to 10 m) and a maximum width of approximately 2 m. The standard configuration uses four color bars (CMYK) with a resolution of 400 dpi, which allows for high-quality, 4-colors printing of any digital image.
Globus Digital Printing solutions are marketed under the COILOR brand.
Globus Digital Printing solutions are the result of an R&D program which lasted three years and led to the installation, in 2018, of a Pilot Line used to optimize the process in cooperation with Globus printer supplier partner.
The pilot line was used to test various combinations of base coating and printing inks. As a result, Globus is able to suggest a “starter kit” of consumables to those customers who are new to the printing process and want to start entering the market while carrying ahead their own technology tests and developments.
Globus's Digital Printing solutions have now matured into an industrial-scale process, garnering market interest and recognition and opening new avenues for precoated strips. Users have recognized the advantages brought by this innovative product, which opens new markets and applications to the precoated strips.
The printing process integrates seamlessly into existing Coating Lines or operates as a stand-alone, individual line. Opting for the latter, the Printing Line is usually completed by a Clear Coating Section which applies a transparent, protective coating over the printed surface, enhancing durability.
The printing process is a single pass, and it is based on the CMYK color model - Cyan, Magenta, Yellow, and Key (black) - which allows printing of every needed color shade. For this reason, the minimum printer layout includes four bars, each representing a distinct color, for comprehensive color coverage.
The UV oven can use different types of lamps, to match the process needs. The most common lamps are the Hg and the Fe ones.
The UV-curing process has both environmental and economic benefits if compared to traditional ovens because it avoids the VOC generation and the need to process the exhaust before discharging it into the atmosphere. The energetic demand of the curing equipment is also much lower.
To ensure mechanical resistance and longevity, a protective clearcoat is applied over the print.
This clearcoat can be solvent-based, applied via roll-coater and thermally cured, or solvent-free, such as electron-beam curable coatings, making the process nearly VOC-free (aside from primer application). This approach significantly enhances environmental sustainability by reducing emissions and energy consumption.
Leveraging extensive expertise in both solvent-based and solvent-free coatings, Globus offers optimal equipment configurations and features, customized to meet specific user requirements, ensuring superior finishing quality and efficiency.