With today's population being more conscious and aware of the environmental footprint that an individual leaves on the planet, more pressure is being put on the manufacturing industry to use recyclable and renewable materials. The printing industry is far from safe from such pressures. This environmental push has introduced a higher variety of recycled paper fibers into the paper making process. This pushes one to think if the industry is sacrificing the folding endurance, in turn, the durability of our printed products by introducing more recycled materials into the production stream. Recycling paper has always been part of one of the branches of the paper making process. First invented by the Japanese in the 11th century and then popularized by William Rittenhouse in the 1690s, the manufacturing process of recycling paper fibers soon became a staple in the printing industry.
Both recycled and virgin fibers can be used interchangeably for all printed products with the exception of higher end products that are usually made out of virgin fibers. Some recycled fiber paper may give a product higher marketing value due to the label of "recycled". The issue at hand is that while mostly interchangeable in use, the fibers are not made equal. The process of recycling the paper fibers includes water being added to the paper to create a slurry that in theory separates all of the ink, glue, plastic film and staples. This process unfortunately is not perfect because throughout the recycling process the fibers in the paper loose length consistency and strength. Contaminants in the forms of binders, inks and solvents cannot be entirely removed and therefore they get carried over into future recycled products. With this information at hand it is easy to hypothesize that recycled fibers are generally weaker than virgin fibers with a further decrease in strength due to contamination in turn creating printed products that have a low folding endurance. The methods used for the experiments include folding endurance testing of both recycled and virgin fiber substrates with / without ink and the use of a microscope to evaluate the paper fibers. The papers were sourced from Spicers whom provided a variety of substrates from paper mills such as Domtar, Rolland, and International. Both Flexographic and Lithographic inks were used for a wider data set.
Throughout this research paper raw folding endurance data is analyzed to show the real effects that recycled fibers have on the durability of our printed products. The results showed that while environmentally friendly papers underperformed in retaining strength when inks are added to the folding endurance testing, the substrate on average has a higher endurance rate than virgin fiber paper. The theory is that the addition of binders to the recycled fiber papers strengthen the overall paper endurance. Perhaps recycled fiber papers can withstand the test of time better than virgin fiber papers as well however this is a test for another time.