Sean Milmo, European Editor09.23.16
In order to conserve resources, combat climate change and protect the environment, a long-term objective of the European Union and European national governments is the creation of a circular economy centered on recycling.
The aim is to reuse, repair, refurbish and recycle the great majority of materials and products so that Europe can be far more resource efficient. At the moment, it is the world’s most dependent region on imported raw materials.
For the printing industry, particularly ink producers, the drive towards a circular economy could pose a major challenge.
The Importance of Deinking Paper
The paper sector is one of Europe’s and the world’s leading recyclers, with a recycling rate of more than 70%. Approximately 90% of newspapers in Europe are printed on recycled paper, while the same proportion of corrugated boxes are made of recycled fiber and over half of fibers used in new paper and board are sourced from recovered paper, according to figures from the Brussels-based European Recovered Paper Council (ERPC).
Users of paper in sectors other than carton and board and newspapers want access to more recyclate. However, insufficient quantities of it are available with high enough quality.
There is increasing pressure on the paper and print industry to improve the efficiency of the deinking process. As concepts of the circular economy are applied regionally and nationally, particularly in northern Europe, brand owners and retail chains and their print suppliers are demanding evidence of uncontaminated paper recyclate.
As a result, European eco label schemes like the EU Ecolabel and Germany’s Blue Angel are stipulating that recycled printed products must have been subject to a high level of deinking before they will be certified.
Public procurement policies are even being changed to encourage deinking. Government bodies are wanting eco label certification from print suppliers. Some companies are preparing for a tightening of the rules with the prospect that eco labeling could be extended into new areas like books.
“Already one school books publisher in Germany has decided to opt for improved deinking of the recycled paper it uses in school text books because it is anticipating the German education ministry could soon demand eco labeling of school text books,” said Axel Fischer, public relations manager at the International Association of the Deinking Industry (INGEDE), Munich.
EcoFolio, a French agency that has been given responsibility by the French government to encourage paper recycling, has been offering financial incentives to increase the rate of deinking in an effort to raise demand for recyclate.
“The (print) market no longer expects recycled papers to have no better than newsprint quality,” said Laurel Brunner, convenor of a working group of the Geneva-based International Organisation for Standardisation (ISO), which has been drawing up a new set of standards on deinking to complement several existing ones. “Nowadays we expect to have the option of using recyclates even for the most beautiful of graphic papers.”
The lack of quality recycled paper is blamed by the printing sector and its ink suppliers to a reluctance of paper mills to adopt new deinking technologies, while the mills are complaining that the ink producers should be doing more to adapt their inks to deinking processes.
“These differences between the two sectors of the industry have to be resolved sooner or later,” said one deinking consultant. “The industry needs to work closely together to find more effective ways of deinking the inks which are difficult to remove entirely from recycled paper.”
These “problem” inks include certain types of waterborne inks and flexo, UV and digital inks, in particular inkjet inks and some liquid toners.
Critics claim that there are difficulties with eliminating these inks because of the predominance in Europe of one system of paper recycling based on the traditional single-loop process of alkaline floatation.
This is monitored by a dual quality control scheme, which first assesses the deinkability of printed products and then evaluates the completeness of the deinking.
The deinkability assessment is based on a scorecard drawn up by the European Recovered Paper Council (ERPC), whose members include Europe’s main printing and paper industry association and is supported by the European Printing Ink Association (EuPIA). The scorecard covers five parameters – luminosity, color, cleanliness, ink elimination and filtrate darkening.
The evaluation is conducted through a test called Method 11, created by INGEDE itself, whose membership consists of the vast majority of the Europe’s recycling paper mills.
Most eco labels in Europe use data from ERPC scorecard and the Method 11 test to certify compliance with deinking standards. Some even lay down a minimum threshold of scores from both codes to gain certification.
Some combinations of ink, paper and printing processes are considered to be so compatible with deinking technology that they are being exempted from the need for testing.
These work well within the alkaline floatation system mainly because the ink comprises mostly hydrophobic contaminants. When air is blown through the floatation cell to create a froth. the hydrophobic ink particles attach themselves to the air bubbles to rise to the surface where they can be removed.
The inks that are resistant to this deinking method have hydrophilic elements preventing the inks from detaching themselves from the fibers in the pulp slurry.
“Basically they are comfortable staying in the water,” explained Fischer. “Obviously it can be a difficulty with water-based inks because they have components which are intrinsically hydrophilic. With deinking, waterborne inks are not environmentally friendly. LED UV-curing inks are in the same position because their degree of hydrophilicity. Flexo inks also have the difficulty of being hydrophilic as well.”
With digital inks, inkjet particles can be hydrophilic or are too small to be pulled to the surface. Inkjet dyes merge with the fibers to become almost unmovable. With liquid toners, the problem is that the polymer films break into large pieces of agglomerated particles, which are too heavy to come to the surface.
However, with a new ink for its RotaJET L digital press, the German press manufacturer Koenig & Bauer (KBA) has developed a formulation where the agglomeration of the polymer particles allows floatation because they have hydrophobic surface properties.
In its Jet Press 720, Fujifilm uses an inkjet ink that is applied to paper coated with precipitated calcium carbonate to react with magnesium to form pigment agglomerations, which boost both the color quality of the print and help the deinking process. “It is a similar agglomeration process to that used in detergents,” said Fischer.
INGEDE claims that the introduction of these successful ink technologies that are compatible with floatation deinking shows that inks with hydrophilicity difficulties can be adapted to the process.
The association is currently working with Landa of Israel on making the ink in its offset/digital Nanograph Printing machine deinkable in the floatation system.
“When it is applied with a low ink coverage, we have found in our tests that it is deinkable,” Fischer said. “But when used with a thicker ink coverage, it makes agglomerations of polymer which are too heavy to work properly with the floatation process.”
Landa, which is preparing for the launch of Nanograph, confirmed in a statement that the company is “working closely with INGEDE, to achieve certification for all its Nanograph presses.”
However, HP, whose Indigo printing technology with a similar polymer film process was invented by Landa’s founder Benny Landa, is looking for a different deinking solution to that of the single-loop floatation process.
“(We’ve) invested considerable resources in developing a fundamental understanding of the key factors affecting deinkability and in new deinking chemistries,” said a company spokesperson.
“(We’ve) invested considerable resources in developing a fundamental understanding of the key factors affecting deinkability and in new deinking chemistries,” he continued. “These findings have been shared with the deinking community at various scientific and industry forums. Collaboration is being discussed with various paper companies and paper institutes to explore opportunities for exploiting HP’s research on an industrial scale.”
HP and other printing equipment companies have been investigating the feasibility of achieving successful deinking in the floatation process with double or even triple loop feeds. Some have even been looking at entirely different technologies like enzymatic and adsorption systems.
“A lot of the successful tests being carried out on the deinking of digital materials has been in mixes with other printed products with the digital print being limited to a share of the total of 5% to 10%,” said Alexander Schiller, a researcher at Germany’s Graphic Technology Research Association (Fogra). “When digital prints gains a much greater share of the print market, there is a danger that suitable deinking technologies will not be available to handle much larger quantities.”
Among the standards-setting organizations, ISO appears to want to give paper users more choice of technologies. Its working group focusing on deinking has been seeking to draw up standards similar to those applied to the quality control of a raw materials.
“(The demand for high quality recyclates) requires new approaches to deinking and technologies that can remove even the most tenacious of inks,” Brunner noted.
In other words deinking processes have to be appropriate for dealing with the characteristics of the ink in the printed products not the other way round.
This is an approach consistent with the EU’s Waste Framework Directive, which underpins the Union’s policy on recycling and stipulates that priority should be given to the recycled product rather than the recycling process.
Nonetheless, the main driver could in the end be costs, which is a major reason for the current domination of the alkaline floatation process in Europe.
“The process was developed because the main attraction behind the introduction of recycled paper was the availability of a source of relatively cheap raw material,” said Fischer. “That is still the case. Deinking has to be part of a continuous process that cannot stop to deal with different grades of printed products. A typical 200,000-300,000 tons-a-year recycling plant has to lose only a tiny proportion of its yield and it becomes uneconomical.” n
European Editor Sean Milmo is an Essex, UK-based writer specializing in coverage of the chemical industry.
The aim is to reuse, repair, refurbish and recycle the great majority of materials and products so that Europe can be far more resource efficient. At the moment, it is the world’s most dependent region on imported raw materials.
For the printing industry, particularly ink producers, the drive towards a circular economy could pose a major challenge.
The Importance of Deinking Paper
The paper sector is one of Europe’s and the world’s leading recyclers, with a recycling rate of more than 70%. Approximately 90% of newspapers in Europe are printed on recycled paper, while the same proportion of corrugated boxes are made of recycled fiber and over half of fibers used in new paper and board are sourced from recovered paper, according to figures from the Brussels-based European Recovered Paper Council (ERPC).
Users of paper in sectors other than carton and board and newspapers want access to more recyclate. However, insufficient quantities of it are available with high enough quality.
There is increasing pressure on the paper and print industry to improve the efficiency of the deinking process. As concepts of the circular economy are applied regionally and nationally, particularly in northern Europe, brand owners and retail chains and their print suppliers are demanding evidence of uncontaminated paper recyclate.
As a result, European eco label schemes like the EU Ecolabel and Germany’s Blue Angel are stipulating that recycled printed products must have been subject to a high level of deinking before they will be certified.
Public procurement policies are even being changed to encourage deinking. Government bodies are wanting eco label certification from print suppliers. Some companies are preparing for a tightening of the rules with the prospect that eco labeling could be extended into new areas like books.
“Already one school books publisher in Germany has decided to opt for improved deinking of the recycled paper it uses in school text books because it is anticipating the German education ministry could soon demand eco labeling of school text books,” said Axel Fischer, public relations manager at the International Association of the Deinking Industry (INGEDE), Munich.
EcoFolio, a French agency that has been given responsibility by the French government to encourage paper recycling, has been offering financial incentives to increase the rate of deinking in an effort to raise demand for recyclate.
“The (print) market no longer expects recycled papers to have no better than newsprint quality,” said Laurel Brunner, convenor of a working group of the Geneva-based International Organisation for Standardisation (ISO), which has been drawing up a new set of standards on deinking to complement several existing ones. “Nowadays we expect to have the option of using recyclates even for the most beautiful of graphic papers.”
The lack of quality recycled paper is blamed by the printing sector and its ink suppliers to a reluctance of paper mills to adopt new deinking technologies, while the mills are complaining that the ink producers should be doing more to adapt their inks to deinking processes.
“These differences between the two sectors of the industry have to be resolved sooner or later,” said one deinking consultant. “The industry needs to work closely together to find more effective ways of deinking the inks which are difficult to remove entirely from recycled paper.”
These “problem” inks include certain types of waterborne inks and flexo, UV and digital inks, in particular inkjet inks and some liquid toners.
Critics claim that there are difficulties with eliminating these inks because of the predominance in Europe of one system of paper recycling based on the traditional single-loop process of alkaline floatation.
This is monitored by a dual quality control scheme, which first assesses the deinkability of printed products and then evaluates the completeness of the deinking.
The deinkability assessment is based on a scorecard drawn up by the European Recovered Paper Council (ERPC), whose members include Europe’s main printing and paper industry association and is supported by the European Printing Ink Association (EuPIA). The scorecard covers five parameters – luminosity, color, cleanliness, ink elimination and filtrate darkening.
The evaluation is conducted through a test called Method 11, created by INGEDE itself, whose membership consists of the vast majority of the Europe’s recycling paper mills.
Most eco labels in Europe use data from ERPC scorecard and the Method 11 test to certify compliance with deinking standards. Some even lay down a minimum threshold of scores from both codes to gain certification.
Some combinations of ink, paper and printing processes are considered to be so compatible with deinking technology that they are being exempted from the need for testing.
These work well within the alkaline floatation system mainly because the ink comprises mostly hydrophobic contaminants. When air is blown through the floatation cell to create a froth. the hydrophobic ink particles attach themselves to the air bubbles to rise to the surface where they can be removed.
The inks that are resistant to this deinking method have hydrophilic elements preventing the inks from detaching themselves from the fibers in the pulp slurry.
“Basically they are comfortable staying in the water,” explained Fischer. “Obviously it can be a difficulty with water-based inks because they have components which are intrinsically hydrophilic. With deinking, waterborne inks are not environmentally friendly. LED UV-curing inks are in the same position because their degree of hydrophilicity. Flexo inks also have the difficulty of being hydrophilic as well.”
With digital inks, inkjet particles can be hydrophilic or are too small to be pulled to the surface. Inkjet dyes merge with the fibers to become almost unmovable. With liquid toners, the problem is that the polymer films break into large pieces of agglomerated particles, which are too heavy to come to the surface.
However, with a new ink for its RotaJET L digital press, the German press manufacturer Koenig & Bauer (KBA) has developed a formulation where the agglomeration of the polymer particles allows floatation because they have hydrophobic surface properties.
In its Jet Press 720, Fujifilm uses an inkjet ink that is applied to paper coated with precipitated calcium carbonate to react with magnesium to form pigment agglomerations, which boost both the color quality of the print and help the deinking process. “It is a similar agglomeration process to that used in detergents,” said Fischer.
INGEDE claims that the introduction of these successful ink technologies that are compatible with floatation deinking shows that inks with hydrophilicity difficulties can be adapted to the process.
The association is currently working with Landa of Israel on making the ink in its offset/digital Nanograph Printing machine deinkable in the floatation system.
“When it is applied with a low ink coverage, we have found in our tests that it is deinkable,” Fischer said. “But when used with a thicker ink coverage, it makes agglomerations of polymer which are too heavy to work properly with the floatation process.”
Landa, which is preparing for the launch of Nanograph, confirmed in a statement that the company is “working closely with INGEDE, to achieve certification for all its Nanograph presses.”
However, HP, whose Indigo printing technology with a similar polymer film process was invented by Landa’s founder Benny Landa, is looking for a different deinking solution to that of the single-loop floatation process.
“(We’ve) invested considerable resources in developing a fundamental understanding of the key factors affecting deinkability and in new deinking chemistries,” said a company spokesperson.
“(We’ve) invested considerable resources in developing a fundamental understanding of the key factors affecting deinkability and in new deinking chemistries,” he continued. “These findings have been shared with the deinking community at various scientific and industry forums. Collaboration is being discussed with various paper companies and paper institutes to explore opportunities for exploiting HP’s research on an industrial scale.”
HP and other printing equipment companies have been investigating the feasibility of achieving successful deinking in the floatation process with double or even triple loop feeds. Some have even been looking at entirely different technologies like enzymatic and adsorption systems.
“A lot of the successful tests being carried out on the deinking of digital materials has been in mixes with other printed products with the digital print being limited to a share of the total of 5% to 10%,” said Alexander Schiller, a researcher at Germany’s Graphic Technology Research Association (Fogra). “When digital prints gains a much greater share of the print market, there is a danger that suitable deinking technologies will not be available to handle much larger quantities.”
Among the standards-setting organizations, ISO appears to want to give paper users more choice of technologies. Its working group focusing on deinking has been seeking to draw up standards similar to those applied to the quality control of a raw materials.
“(The demand for high quality recyclates) requires new approaches to deinking and technologies that can remove even the most tenacious of inks,” Brunner noted.
In other words deinking processes have to be appropriate for dealing with the characteristics of the ink in the printed products not the other way round.
This is an approach consistent with the EU’s Waste Framework Directive, which underpins the Union’s policy on recycling and stipulates that priority should be given to the recycled product rather than the recycling process.
Nonetheless, the main driver could in the end be costs, which is a major reason for the current domination of the alkaline floatation process in Europe.
“The process was developed because the main attraction behind the introduction of recycled paper was the availability of a source of relatively cheap raw material,” said Fischer. “That is still the case. Deinking has to be part of a continuous process that cannot stop to deal with different grades of printed products. A typical 200,000-300,000 tons-a-year recycling plant has to lose only a tiny proportion of its yield and it becomes uneconomical.” n
European Editor Sean Milmo is an Essex, UK-based writer specializing in coverage of the chemical industry.