In the case of FSC – which is probably the most widely used worldwide – label converters that become certified are eligible for an on-product FSC logo use that ensures CoC certification and provides their customers with a guaranteed FSC product. Essentially, the basis of the CoC certification is that any FSC labeled product can be traced back to a certified source (see flow chart above).
A brief outline of the main organizations that label paper mills work with for certification and chain-of-custody verification are:
Forest Stewardship Council - The Forest Stewardship Council (FSC) is also a non-profit organization that encourages responsible management of the world’s forests and provides global standards for forest management which cover a balance of environmental, social and economic aspects. The well-being of forest communities and ecosystems is as important as replacing trees in ensuring the future of the world's forests.
The FSC system also provides a way of tracking forest products through independently verified and documented CoC certification. This has to cover every stage in processing, conversion, distribution and printing before the final product can carry the FSC logo.
The FSC's international headquarters are located in Bonn, Germany, but contact persons and national offices can be found today in more than 40 countries, thereby creating a truly global FSC network.
Carrying the FSC certification logo on a label converter’s products tells the label industry, customers and market that they support the highest social and environmental standards in the markets and applications where the labels are produced and used. However, for a label to carry the logo it must be printed on FSC paper by an FSC certified label converting company.
FSC certification is supported and encouraged by major worldwide trusted environmental organizations that include well-known names such as Greenpeace, National Wildlife Federation, The Nature Conservancy and the World Wildlife Fund.
Label users and consumers wishing to support healthy forests and communities should look and ask for FSC, or other certification, labels when purchasing label paper products.
Sustainable Forest Initiative - SFI Inc. is a fully independent, charitable organization dedicated to promoting sustainable forest management. Its forest certification standard is based on principles that promote sustainable forest management, including measures to protect water quality, biodiversity, wildlife habitat, species at risk and forests with exceptional conservation value. The standard is used widely across North America, and has strong acceptance in the global market.
SFI chain-of-custody certification extends into the market by tracking fiber content from certified lands through production and manufacturing to the end product, so that consumers who buy products with the SFI ‘percent-content’ label know they are buying products from responsible sources.
The SFI labels are recognized globally and provide a visual cue to help customers source certified forest products.
Programme for the Endorsement of Forest Certification (PEFC) schemes - The PEFC Council is an independent, non-profit, non-governmental organization founded in 1999 which promotes sustainably managed forests through independent third party certification. PEFC provides an assurance to purchasers of paper products which ensures that they are promoting the sustainable management of forests.
There is also a Finnish Forestry Certification Scheme (FFCS) that was developed by the forestry sector and forest owners. This scheme is one of a number that now operate under the PEFC umbrella.
USING PAPER WITH A RECYCLED CONTENT
An increasing number of label papers now have some level of recycled fiber content. However, paper cannot be recycled indefinitely as the fibers will gradually get shorter and weaker. This means that some virgin tree pulp must be introduced into the process so as to maintain the strength and quality of the fiber and finished paper.
Using recycled paper fibers in label papers is claimed to use between 28 percent and 70 percent less energy, save up to 55 percent in water consumption and also substantially reduce carbon emissions – in some label paper mills by up to 20 percent. The use of recycled content label papers therefore already makes sound economic and environmental sense.
In addition, recycled paper also produces fewer polluting emissions to air and water. It is not usually rebleached and where it is, oxygen rather than chlorine is usually used. This reduces the amount of any dioxins which are released into the environment as a by-product of the chlorine bleaching processes, and also keeps waste out of landfills. So, using recycled paper in label grades is seen as being particularly environmentally friendly.
However, it should be noted that there are different sources of paper waste fibers that can be used as a source material for manufacturing recycled paper grades and the label converter may wish to be aware of which sources are the most acceptable:
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Mill broke for example is ‘waste’ paper which has never been used by consumers and may include paper mill waste, laminator waste, printer waste, reel ends, off cuts or rolls damaged during production. When mixed with water the fibers from this waste are freed into pulp.
However, it should be noted that the National Association of Paper Manufacturers does not recognize a paper as recycled if it contains more than 25 percent mill broke and/or virgin wood pulp.
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Post-consumer waste (PCW) is waste paper which has been printed on and used and then collected for recycling; it is seen as more problematic because it needs to have ink and other contaminates removed from it during the pulping stage – but still it is worthwhile. Although the de-inking process uses water and chemicals, it is still less harmful to the environment than the manufacturing process of new paper. Indeed, detergents are used to float-off the ink, where it is removed, solidified and then used for the production of products such as cat litter and soil conditioners.
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Release liner waste is now starting to be collected by organizations such as cycle4green in Europe and recycled into new liner grades, in this case, by Lenzing Papier in Austria. The liner is desiliconized and separated in a newly developed process. This is a cost-free collection service for a minimum single pick-up of three tons.
Modern label papers using recycled paper fibers are visually indistinguishable from 100 percent virgin fiber papers. Good quality labelstock grades containing recycled paper are produced by a number of label paper mills and also incorporated into pressure-sensitive laminates.
Apart from certification for papers made from 100 percent certified virgin fibers, the FSC also operates certification for papers which contain 100 percent recycled post-consumer waste (PCW) – another for papers with at least 85 percent post consumer; the balance preconsumer, and a third being a credit account of post and preconsumer (no virgin fiber).
Arjowiggins, for example, now offers an eco-friendly one-sided label paper that combines 60 percent certified recycled pulp with 40 percent FSC-certified virgin fiber pulp. Other suppliers, such as Avery Dennison, offer label grade papers that are, say, 30 percent post-consumer waste.
With such possibilities on the market, label converters should review the ranges of recycled content label paper grades available from their labelstock or laminate producers and assess their possible usage and applications with their customers.
USING THINNER, LIGHTER AND REDUCED BASIS WEIGHT PAPERS
In recent years considerable work has been undertaken by paper mills to reduce the amount of fiber that goes into label grades, gradually reducing the basis weight, making the papers thinner and lighter – but without affecting the paper’s performance during printing, converting or application.
Constant quality improvements over the years have permitted the use of lower grammage/basis weight papers for labelstock and label liner applications. A reduction from 67 to 60 g/m. for example, can save over ten percent of liner material for each million square meters of labels converted. Some label grades of face or liner paper may today be as low as 50 g/m. or even down as low as 25 g/m.. Such reductions also mean more paper will be on rolls. In turn, longer rolls allow considerable savings on core and wrapping materials as well as on roll-change-related waste in the manufacturing process – and longer running between reel changes.
In addition, improvements in surface properties of, say, pressure sensitive liner grades have enabled significant reductions of silicone coat weight over the years, and/or lower curing temperatures. Add all these elements together and that’s quite an achievement in today’s environmentally challenged world. It therefore makes sense for both label converters and buyers to use thinner labelstocks wherever feasible.
USING CHLORINE-FREE OR OTHER CHEMICAL-FREE PAPERS
A number of different chemicals are involved in the pulping stage of papermaking. Of these, chlorine – which has traditionally been used for bleaching wood pulp to make it white – is amongst the most damaging.
However, most paper mills, especially those found in Europe and North America, now produce ‘Elemental Chlorine Free’ (ECF) papers which are bleached through the use of oxygen, chlorine dioxide or other chemicals instead of using chlorine gas. This is a much less environmentally damaging pulp producing process and is an important consideration in the gradual elimination of dioxide created by chlorine bleaching.
Even better for the environment are those paper mills that use a Totally Chlorine Free (TCF) technology. These are papers bleached without the use of any chlorine compounds at all. Indeed, in countries like Sweden and Germany, chlorine-free papers are regularly produced. Sweden, for example, has a law that requires the elimination of organochloride emissions from paper.
There is arguably little difference between paper grades that are ECF and TCF in their environmental impact on the pulp bleaching process, and both are significantly less polluting than traditional chlorine gas methods. Tremendous progress has been made in these areas in recent years. Any paper brands carrying the Blue Angel mark are certainly required to be TCF.
In terms of recycled paper, a Processed Chlorine Free (PCF) process is used for some recycled grades. Blue Angel is perhaps recognized as the most stringent labeling system for recycled paper. This requires a minimum of 51 percent printed and domestic/office waste and also requires companies to report on the energy used in the manufacturing process.
While chlorine free papers are now widely used, there is also a requirement for some other types of paper that are free of certain other chemicals. Acid-free label papers, for example, have specific applications and have also gained increasing interest. These are papers which contain no free acid and have a pH value of 7.0 or greater. Such papers may be produced from cotton fibers or chemical wood pulps, or virtually any other fiber.
However free of acid the paper may be after manufacture, it must also not have aluminum sulfate (alum) sizing applied to the surface. Unless the paper has been buffered with a substance capable of neutralizing acids (calcium carbonate), it is still possible that pollution in the atmosphere will make the paper acidic over time.
The term ‘acid-free’ does not necessarily mean the paper is safe to use in, say, archival applications. The label converter will need to look for additional specification on what the paper is made of, cotton or purified wood pulp, buffering content and whether neutral or alkaline sizing is used.
In general, acid-free specified paper grades are required for archivists, conservators, curators and other collection-care specialists who need a variety of acid-free label formats for their laser printers. Stickers for children and foods may also need to be acid-free. It is said that acid-free papers are brighter and cheaper than acid-containing papers.
CO.-free papers are also available, but on a limited basis due to the number of certifications held. The CO. footprint for the paper is calculated using the IPCC method which accounts for the most important greenhouse gases.
Label converters and their customers should again be reviewing the label papers that they use to determine, if possible, their chemical content and use or recommend those EFC, TCF, PCF, CO.-free or acid-free grades most suitable to the their products and applications.
USING COMPOSTABLE AND BIODEGRADABLE PAPERS
In some label applications today there is a need for a (self-adhesive) roll-labelstock that is biodegradable or compostable so as to comply with ISO 14855 or EN13432. ISO 14855 is the standard that determines the ultimate aerobic biodegradability of materials under controlled composting conditions. EN13432 is the European compostable standard, if the label represents less than one percent of the total packaging weight, and where biodegradability certification is required.
According to the EN13432 standard, for example, a compostable material must meet three conditions:
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Biodegradation - The compostable material must break down through microbial action producing only carbon dioxide, water and humus (soil). The standard dictates that this process must be 90 percent complete within six months
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Disintegration - The compostable material must satisfy a disintegration test three months after the composting process begins. The standard demands that no more than 10 percent of the original mass of material have particle sizes greater than 2mm after this three month period
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Absence of toxic materials - When fully composted the compostable material must have no negative effects on the composting process. This is checked by a composting test
Some label material suppliers now offer materials to meet these standards; in particular, materials that are suitable for organic food packaging and branded products where the label needs to be compostable with the packaging, as well as for shelf-stable and chilled products that need to be environmentally friendly. Label substrate options include white elemental chlorine free (ECF) non-coated, semi-gloss and kraft natural unbleached papers. These substrates need to be used with a fully biodegradable/compostable, environmentally benign, eco-friendly adhesive, such as products described under the next heading.
USING ECO-FRIENDLY, ENVIRONMENTALLY BENIGN ADHESIVES
Over the past few years there have been increasing numbers of inquiries for adhesive products that have any kind of ‘green’ attributes, and that certainly includes things like environmentally benign adhesives, adhesives for recycling compatibility, adhesives that can be composted, bio-degradable adhesives, adhesives that can be easily removed or washed off, etc. See Figure 3.3.
USE OF PLA STARCH-BASED BIO-PLASTIC FILMS
Bio-plastics are films made from renewable plants such as potatoes and corn (plants that grow every year), although almost any plant available in sufficient quantities can be used. The starch found in these plants is processed and produces a polymer – Poly Lactic Acid (PLA) – which can be used to produce a plastic film for labels that will behave in a similar way to conventional oil-based plastics.
These bio-plastics require less energy to make than conventional plastics. In addition, the bio-plastics films have a lower carbon emission footprint when compared with conventional plastics, and are compostable – making them a particularly ‘green’ choice for label converters and users.
With oil being a finite resource that takes millions of years to form, the use of bio-based film materials is an important step towards a renewable economy.
Being compostable, bio-plastics will biodegrade down to small pieces within 90 days, without leaving any toxic residue under industrial composting conditions, so meeting all three conditions – biodegradation, disintegration, absence of toxic materials – in international standards such as the EN13432 (the European compostable standard, used where the label represents less than one percent of the total packaging weight, and where biodegradability certification is required).
Bio-plastics are recyclable, both mechanically (reconstituting and reusing the material) and also chemically (i.e. with PLA, breaking the polymer down into lactic acid then reforming the bio-plastic), but they must not have any part in possible contamination in the recycling operation.
Bio-plastics such as EarthFirst PLA film from Plastic Suppliers come in both white and clear for labels and can be used in cut and stack or pressure sensitive applications. The film is ideal for uses that call for the modern, no-label look because of its exceptional clarity and gloss. The film is regarded as an environmentally friendly product that can accompany returnable bottles to limit waste and uphold reusability. However, they must not contribute to any contamination of reuse or recycling operations.
The breathability of EarthFirst PLA film enables the underlying adhesive to dry through the label, while the film exhibits excellent resistance to alcohol, grease and oils and is approved for food contact in Europe, Canada and the US.
USE OF BIO-PLASTIC COMPOSTABLE SHRINK SLEEVE LABELS
Degradable/compostable shrink sleeve labels are also now available on the market. Sleever International in France, for example, offers Biosleeve PLA sleeve labels that degrade in 45 days at 60°C and meet the ISO 14855-2:2007 degradability/compostability standard. The PLA film used biodegrades into water, carbon dioxide and nontoxic biomass through the action of micro-organisms present in composting facilities.
Another product is the EarthFirst TDO polylactide (PLA) label available from Printpack’s Seal-It division in Farmingdale, New York, which is said to be ideally suited for current uniquely-shaped containers. It shrinks at substantially lower temperatures and allows the user to attain savings in energy consumption while also increasing productivity.
EarthFirst TDO shrink film has a natural dyne level of 38, giving the user an excellent printing surface, and is scuff resistant, FDA compliant and made from the sustainable resource of corn. It is compostable at temperatures of more than 58°C and 80 percent RH into water and CO. and available in various thicknesses from 40 microns up to 100 microns.
USE OF CELLULOSE FILMS FROM SUSTAINABLE WOOD PULP
Cellulose films are produced from renewable, sustainable wood pulp, which has been sourced exclusively from plantations operating sustainable forestry principles. They offer a range of unique attributes which conventional plastic films are unable to equal, and can also be supplied in a wide range of brilliant colors. Such films are already used for the production of both pressure sensitive and wet-glue cut and stack labels and can offer a no-label look on glass and high clarity plastic bottles as an alternative to, say, polypropylene.
No capital expenditure is required for new labeling equipment when converting from oil-based to cellulose label films. The water permeability characteristic of bio-film products such as Rayothene regenerated cellulose film enables labels (with the correct adhesive) to be washed off returnable bottles using conventional washing techniques – such as high-temperature caustic wash water that penetrates the label and attacks the adhesive in either wet-glue or pressure-sensitive labeling applications. The cellulose sinks in water to allow effective label waste collection.
The washed bottle with the label removed can then be reused in a returnable bottling stream.
Other cellulose label films, such as Clarifoil and Integuard, have also found applications in security label production. Offering good film stiffness for automatic handling, waste stripping and die-cutting, Clarifoil label films can include tamper-evident capabilities and product authentication features. The film accepts both solvent and water-based adhesives, is readily printed by most processes and accepts foil blocking.
Integuard cellulose label film is designed to fragment should removal of the label be attempted, yet it is engineered to permit label application with fully automated equipment. An optically brightened (OB) version of Clarifoil has been developed for pharmaceutical labeling.
Cellulose films, such as Clarifoil, are safe to incinerate, yielding carbon dioxide and water without toxic residuals when burnt and can be landfilled without risk of any toxic leachate. Under appropriate conditions cellulose film will also biodegrade and is compostable. In the UK for example, legislation categorizes Clarifoil together with paper and board for return and recovery purposes.
USE OF SURFACE-LAYERED CELLULOSE FILMS MADE FROM SUSTAINABLE WOOD PULP
Films such as NatureFlex are again produced from sustainable wood pulp harvested from managed plantations and are at the forefront of developments in biodegradable/compostable and sustainable packaging and labels – and have achieved Carbon/Zero status. These films are certified to both EU (EN13432) and US (ASTM D6400) composting norms and are suitable for both industrial and home composting.
The films are made up of a transparent cellulose base obtained from sustainable wood pulp but are then combined with special compostable surface layers that control moisture permeability. CarbonZero status has also been achieved on the full range of NatureFlex coated biodegradable and compostable films, so reducing their footprint – energy efficiency targets, reduction of solid wastes from facilities, CO2 offsets, examining renewable energy, FSC certification of base materials.
A new film in the range, NatureFlex NK, offers not only biodegradability and compostability, but also a moisture barrier approaching that of co-extruded OPP, and claims to have the best moisture barrier of any bio-polymer film currently available – achieved through manufacturer Innovia Films’ unique coating technology.
NatureFlex films are grease, oil and fat resistant, have a good gas/odor barrier and a low static.
IN-MOLD MATERIALS
The inherent qualities of in-mold labels – as the label material becomes a part of the container, requires no release liner for application, and uses no adhesive or post-mold flame treaters – make for rather a sustainable packaging. In-mold labels typically use a thin material and can be produced using a polymer-based ink so there's no contamination. The label and the container become one piece upon application, making it possible to recycle the entire product.
USE OF ADHESIVES WITH BIO-PLASTIC AND COMPOSTABLE FILMS
To complement the properties of the latest bio-plastic, cellulose and surface layered cellulose films, they are best used with recycling compatible or environmentally-benign pressure sensitive adhesives that will break down, if not completely, during the composting process and do not contain any organic solvents. They can then provide environmentally beneficial alternative films to the traditional polyethylene or polypropylene label films and will meet the appropriate international EN 13432 or ISO 14855 standards.
USE OF LIGHTER, THINNER AND STRONGER CONVENTIONAL PLASTIC FILMS
While one of the key trends in filmic label materials has been a move towards sustainable and new eco-friendly options such as bio-plastic films, there has also been a significant move with conventional oil-based films to lighter film gauges and higher label strength films that are becoming closer than ever to paper labels in cost and which provide more labels per roll, longer press running time, reduced material weight and less reel-end and handling wastage.
In particular, the reduction targets set by some leading supermarket and retail groups have led to a new breed of thin films, many of which can be up to 30 percent thinner than current industry standards.
These new thinner engineered and co-extruded films offer a substitute for standard PE and PP facestocks by combining the best properties of both substrates at the same time as using less material. Certainly, significant cost reductions can be achieved by converters moving to lighter weight plastic label films which, when applied, also help to generate less packaging weight.
Thinner film products now available include polyester (PET) face films which have come down to 50 microns; polyester release liners down to as low as 19 microns; clear polyethylene label face films down to 38 microns (also EC and FDA food contact compliant); OPP face films (again EC and FDA food contact compliant) down to 47 microns; and release liners to 38 microns.
The lower caliper of these thinner films, such as 2.5 mil versions of Avery Dennison FasClear and Primax Plus, or Avery Dennison Lean Film in Europe, has the benefit of reducing environmental impact all round — a growing priority for brand owners and retailers. Thinner film, more labels per reel, less stops on the printing press and the label dispensing line, lower weight and bulk for transportation and its associated energy costs, all add up to ‘leaner’ manufacturing, handling and end use. They can also offer full recyclability with polyolefin containers in line with environmental requirements.
Spear, for example, has successfully transitioned over 60 percent of its film customers to the 17 percent thinner material directly diverting five million pounds of pressure sensitive material from going to landfill, with potential to divert another 1.5m pounds once the rest of its client base has switched.
Looking to the future, a label film of only 15 microns thick (they are already used in many flexible packaging applications) could perform its job just as well as those of standard thicknesses, but it would need co-operation between the film producer, press and cutter, and the dispensing machine manufacturer, perhaps with support from a major end-user. Certainly, thinner lean films are already being trialed and can be expected to be introduced as standard products in the future.
Examples of the benefits of thin film liners have also been given by companies such as Evonik Goldschmidt, whose Tego RC Slicone UV release coating applied to 30 micron BOPP is said to reduce total material weight by up to 56 percent when compared to glassine options. The 30 micron UV-siliconized BOPP was also shown to be fully recyclable by regranulization.
THE SHRINK SLEEVE CHALLENGE
Association of Postconsumer Plastic Recyclers
Shrink sleeves present serious challenges to recyclers due to the fact that it is impossible to separate non-compatible shrink materials by weight from PET containers.
Members of the Association of Postconsumer Plastic Recyclers in the US have argued that removing shrink sleeves adds significant costs – 2-4 cents per pound of bottles reprocessed - to their operations, limiting the availability of recycled PET flake.
The range of challenges includes bottle sorting, label removal, use of floatable labels and the impact of ink bleeding on recycled plastic.
De-labeling machines are seen as a stopgap to address shrink sleeves until floatable labels or other solutions are widely adopted.
In Japan, however, a major industry education program has been undertaken to persuade consumers to remove shrink sleeve labels using a tear strip incorporated into the sleeve, allowing separation at source.
Multi-layer shrink constructions with a different molecular weight to PET hold out the possibility of allowing clean separation of shrink material and bottle substrates.
DEVELOPING A CONVERTER POLICY ON THE USE OF LABEL MATERIALS
There is little doubt that the use of environmentally-friendly, recycling compatible label substrates, liners and adhesives will continue to grow. Down-gauging and light-weighting of label paper and films will become more common, new sources of papers fibers are being encouraged, bio-plastics have been developing fast, biodegradable adhesives will be increasingly needed for composting applications, while recyclable and recycled materials will be increasingly demanded.
End-users are continually looking to be ‘greener’ and more environmentally friendly and expect their label converters to be researching, supporting and encouraging the latest developments in eco-materials. Environmental policy statements will become a key part of label sourcing and procurement documents worldwide, with accreditation such as ISO 14001, LIFE, EMAS and FSC perhaps becoming a minimum requirement.
Many of the leading label converters in Europe, North America and elsewhere are already operating to such standards and have prepared and issued their own environmental policy statements with regards to the label materials that they use. These statements usually cover both paper and filmic face and liner materials, as well as the use of adhesives.
If they have not already done so, most other label converters will eventually be expected to have their own environment policy statements and action plans relating to label material usage. To help those converters, this ‘How to’ book has drawn up a guideline policy statement on label materials that they can use or adapt to their own operations, depending on materials used, markets and applications. This is set out below.
Environmental policy on label materials
General
We give preference to suppliers who have formally approved quality, environmental quality and environmental management systems with qualifications such as ISO 9001 and ISO 14001.
Paper materials
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We encourage and promote with our customers the use of chain-of-custody certified face and liner papers that provide a guaranteed product has been tracked from its point of origin to the point of it being printed and dispatched. The papers are either produced from a recycled fiber content and/or virgin fiber obtained from sustainable forests (FSC, FSI or PEFC certified
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We encourage and promote with our customers the use of papers with stringent environmental specifications that include ECF, TCF or acid-free characteristics
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We continue to evaluate and review the use of tree-free papers made from agricultural waste and encourage their use where appropriate
Filmic materials
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We constantly review and promote the availability of thin film constructions that reduce waste, enable more labels per roll, reduce reel changes and encourage shipping efficiencies
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We specify recyclable plastics (PP and PET) where technical requirements allow and continually trial and encourage the use of bio-plastic, cellulose and surfaced layered cellulose films that offer biodegradability and compostability to meet the appropriate international EN 13432 or ISO 14855 standards
Adhesives
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We use environmentally friendly 100 percent solvent-free adhesives – whether water-based acrylic adhesives or hot-melt adhesives – for the majority of applications in preference to solvent-based adhesives
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We are evaluating the use of bio-friendly adhesives and look to encourage their use where technical requirements allow
