„KOPA printing house offering improved environmentally friendly technological solutions“
Last year brought a number of challenges to the business, which forced some undertakings to suspend operations, others to reorient, and others still to use quarantine to restructure for the future. The latter is exactly what we did at our printing house, devoting this period to the development of sustainability topics and searching for more environmentally friendly alternatives.
The ideas of sustainability and ecology have always been important to us in the context of improving production processes. In order to ensure the lowest possible pollution of the environment and to reduce the amount of harmful waste, we started looking for alternatives that would not only be safer but would also allow us to maintain the high quality of our products. In the production of softcover publications, one of the important technological aspects is the choice of adhesives for gluing the book block together and gluing the cover to the spine. There are two main types of adhesive on the market for the production of glued softcover publications (books, magazines, brochures): hot-melt adhesive and polyurethane (hereinafter – PUR) adhesive, which will be discussed below.
Products glued with polyurethane adhesive hold the book block firmly, but products glued with this adhesive are difficult to recycle. Most polyurethanes are thermosetting polymers that do not dissolve on heating and make it difficult for the adhesive to separate from paper. As a result, waste is difficult to dispose of because it emits hazardous chemicals such as isocyanates, hydrocyanic acid and dioxins during the combustion process. After settling in landfills, polyurethane products decompose into hazardous, environmentally harmful substances.
Hot-melt adhesive is often used as an alternative to PUR adhesive in brochure production. This adhesive is easier to recycle and contains fewer substances harmful to the environment; however, it has lower adhesive properties. We set ourselves the goal of conducting a thorough study on whether it is possible to glue the publication using hot-melt adhesive as reliably as with PUR. The hypotheses raised led to tests in which we sought to establish whether the use of alternative, more environmentally friendly adhesives would not harm the quality of the products. We tested eight types of hot-melt adhesive from four manufacturers. To carry out the testing, we invested in a page-pull strength measuring device, which allowed us to obtain objective, measurement-based testing data. By experimenting with adhesives from various manufacturers and changing the gluing temperature and thickness of the adhesive layer, we were able to discover a combination of technological parameters which allowed us to achieve the maximum binding strength of a book with hot-melt adhesive.
Based on the international ISO 19594:2017 standard, which defines the measurement and evaluation of the quality of the adhesive layer of perfect-bound brochures, we have concluded that by using more environmentally friendly hot-melt adhesive for brochures, we can ensure the high quality of the product. During the testing conducted by KOPA, the page-pull strength with the use of hot-melt adhesive exceeded the maximum quality values of the product specified in the standard. This helped us decide that, acting pursuant to the principles of sustainable production, as we can now achieve a binding strength higher than sufficient, we will choose to use hot-melt adhesive in the production of perfect-bound brochures from now on.
The search for more environmentally friendly alternatives has allowed not only technological improvements, but also the creation of an additional customer service. If requested, we are currently the only ones in Lithuania and the Baltic States able to offer our customers the binding strength measurement service of glued brochures in accordance with the international ISO 19594:2017 standard.
Assessed from a sustainability and technological perspective, KOPA’s new hot-melt binding standard will allow us to offer high-quality products to our customers in line with the ISO 19594:2017 standard as an alternative to PUR adhesive technology.