Sustainability, an imperative: India’s label printers make efforts!

Sustainability is the ability to sustain, carry on or endure for longer periods of time. The definition of sustainability has undergone a sea change over the years. Gradually it conveyed the message referring to environmental protection, in real terms it means using natural resources such that their benefits are available to future generations. Moving on, it is the thought process evolved to give back to mother earth, whatever we draw from it. We need to replenish the depleting resources. There was a time when depending on forests for wood to be used in various applications was a way of life, whether it was for construction, furniture, firewood for cooking or heating, or then producing paper. It soon became evident that increasing deforestation was adversely impacting the environment. Reducing forest cover was impacting on animals’ natural habitat leading to human-animal conflict, soil erosion, fewer crops, flooding, disruption of water cycles, greenhouse gas emissions, changes in the climatic conditions. There arose an urgent and imperative need to curtail the depleting forest cover. In India, the government enacted various laws; the Forest Conservation Act of 1980, the Wildlife (Protection) Act of 1972, and the Compensatory Afforestation Fund Act of 2016, along with initiatives like the National Afforestation Program and the Green India Mission. The paper industry rose to the need and started setting up and managing plantations, growing more wood than they consumed. They are now taking more steps using alternate materials like wood chips and veneer waste from the wood industry, agricultural byproducts like sugarcane bagasse, wheat or paddy straw for pulp production and increasing use of recycled paper fibers instead of virgin pulp.

No Label Look

The first half of the 20^th century was witnessing the invention of the wonder material, “Plastics”, the evolution of which is a magical story. It largely replaced glass as packaging material by virtue of which packages became lighter, breakages reduced, aesthetics of packages improved and the “use and throw” or disposable packaging became evident everywhere. Toward the early second half of 20^th century, plastics raw materials had started being manufactured and used in India, the usage spread fast across the country. By the 1970s plastic films gave rise to another rapidly evolving growing industry, “flexible packaging”! Households found it convenient and affordable to buy refill packs. Self-adhesive labels, which were predominantly made of paper until the 1990s, began transitioning to filmic materials. With the transparent films being adopted as face materials, started catching the fancy of the FMCG brands as they also provided the “No-Label Look” which aesthetically appealed to the consumers. While a large part of glass bottles transformed into usage of plastic bottles, the labels evolved from paper to filmic. With the evolution and  growing use, polyethylene as a versatile material, stretchable labels were produced to adorn squeezable shampoo and sauce bottles.

Single use plastics, banned!

It was also until the early 1970s that the primary packaging was labelled glass bottles, the secondary packaging was folding cartons and tertiary packaging was wooden cases. Thereafter kraft paper based corrugated cartons started replacing the heavy wooden cases. The steel strapping used to secure wooden cases was done away with. Glued flaps and remoistenable paper tapes were used to secure the corrugated board cartons, reinforced with plastic strapping. When plastic films evolved in the 1970s, self-adhesive BOPP tapes started being manufactured in India. These BOPP tapes replaced the paper tapes, and their usage grew rapidly across the country. It was a century of plastics! Plastics became a gigantic industry impacting all segments of industry from packaging, to automotive, electronics, sanitary hardware, engineering, hand tools and almost all segments of industry and society. By the 1980s, plastic was recognized as a potential environmental hazard, due to its non-biodegradability. Over the years this problem has escalated with several tons of plastic scrap dumped in oceans, landfills and elsewhere. They break down into microscopic particles that affect the health of humans, marine environments, and wildlife. Governments around the world started to enact laws to reduce the usage of plastics in day-to-day applications. In 2002, Bangladesh was the first country to ban single-use plastic bags and promote the use of jute or cloth bags in an effort protect the environment that was getting polluted due to rampant dumping of plastic bags and packaging. In July 2022 Government of India under their Plastic Waste Management Amendment Rules, 2021, banned the manufacture, import, stocking, distribution, sale, and use of identified single-use plastic items.

Non-renewable energy sources like coal, oil, and natural gas are used to make plastics, contributing to CO2 emissions and climate change. To reduce the impact and aid sustainability, Indian government started to promote the renewable energy sources like solar power, replacing fuel run passenger vehicle with electric vehicles, encourage and drive in programs leading to afforestation, preservation of water resources like rivers and water bodies, etc. These endeavors have led to the adoption of the principal of  four Rs of sustainability which are Reduce, Reuse, Recycle, and Recover leading to minimizing waste and resource consumption, promoting environmental responsibility, and fostering a circular economy. 

Reduce: It is making efforts to minimize waste and using less materials to arrive at the final product. Examples of industry’s efforts include; In 2022 liquor major Pernod-Ricard decided to do away with the secondary packs, the monocartons. This resulted in reduction of  7310 tons of carbon emissions every year while saving 2.5 lakh trees and reducing the waste going to landfills by 18745 tons. Diageo, another leading beverage brand, followed suit.

Reuse: We remember that in old times we used to have soft drink and beer bottles that were reused, though that concept has not re-emerged to the complexities involved in collection and cleaning, but several companies promote containers that find use after consumption of contents, reusable shopping bags are being preferred, and clothes also find usage after repurposing.

Recycle: This is a very important part of sustainability. It involves sorting to separate used material going waste and reprocessing to create usable material. Materials such as paper, plastic, glass and metal can be reprocessed or recycled to produce usable products.

Recover: This involves generating new products or energy from waste.

For self-adhesive labels industry it is a complex exercise as the label laminate is a multilayered multiple product construction. The label laminate consists of face material, PS adhesive, silicone and release base liner material. 50% of the laminate goes as waste before its application on the end product. The trimming from the slitting of laminate jumbo rolls, the waste matrix after die-cutting with pressure sensitive adhesive on it and the total release liner is waste that is either incinerated or goes to landfills. The label industry recognizes this and realizes that it is time that they make efforts towards  sustainable manufacturing. The author has requested many label printers on their endeavors toward this cause. Some who in numbers are a minor part of the total industry have responded about their efforts. A much larger effort is needed for the sake of this noble cause of sustainability, environmental protection and saving the depleting of natural resources for future generations. The responses are listed below.

Kuldip Goel of ANY Graphics NOIDA is the past President of Label manufacturers association of India and his initiative on sustainability are an inspiration for others in the industry. While building their new factory they have followed IGBC(Indian Green Building Council) Guidelines to create a certified green factory. Their application for Platinum Green Lead Rating which signifies a commitment to achieving the highest level of sustainability and environmental responsibility in building design and construction, is under process. Kuldip adds, “We have unwavering dedication to Innovations, and Sustainability. We have invested in impeccable infrastructure, cutting-edge technology, and a team of skilled professionals to create an environmentally friendly green infrastructure. For using renewable energy, we installed solar panels to generate 700KVA power for our captive use. 50 KL STP (Sewerage treatment plant) and 5KL ETP (Effluent treatment plant) are in place. All lights in the building are LED - to save energy. Our generators are run with PNG (Piped Natural Gas) fuel. The factory rooftop and all sides are insulated to minimize heat transfer between outside and inside. In areas within factory that have higher levels of fumes while in production, TFA AIRCONDITIONING is installed, which means the system has sensor based “Treated Fresh Air” option. There is a centrally located courtyard that has forest inside and the oxygen generated therein is being used in production areas. More than 1000 oxygen emitting trees and plants have been planted. These are special plants and not fancy decorative ones. For facilitating movement of handicapped and physically disabled easy access is provided within the factory premises.”

Krish Chhatwal, Kwality offset New Delhi; We are investing in ecofriendly technologies such as digital printing and waterless printing, to reduce waste, energy consumption, emissions and optimizing our production processes to increase efficiency.

Anuj Bhargav, Kumar Labels Noida; We are now 100% on LED UV with more than 100 units installed under one roof, reducing our energy consumption substantially. We have invested in renewable energy resources; Solar Panel installation is underway. Adopting recyclability, rPET(Recycled PET) liner is commercialized and its usage is growing. rPET labels were commercialized past year and rPET labels on rPET liner have been recently launched. We are committed to remaining sustainable and keep adopting alternatives and available options. 

Rajesh Chadha Update Prints Gurgaon: We are continuously putting  emphasis on energy and waste reduction by investing in right equipment using efficient processes, taking up regular maintenance of machines for optimal performance, training staff toward sustainability. 

Priyank Vasa Unick Fix-a-form Ahmedabad:

We participate in the matrix recycling program run by Avery Dennison for matrix waste and release liner materials saving it from going to landfills, impacting environment. We are getting FSC certification leading to usage of sustainably manufactured paper. We are planning to install rooftop solar panels for captive generation of renewable energy. We offer our customers sustainable products to select from with the help of our label stock suppliers.

Manish Hansoti S.Kumar Multi Products Pvt.Ltd.: 

We reduced energy consumption by implementing energy-efficient lighting and HVAC systems. A 300 KVA solar plant covers 30% of our electricity needs. We implement water-saving measures, including recycling water and using a reverse borewell. We partnered with Avery Dennison to recycle label stock waste and run recycling programs for paper, plastic, and other materials. Most of our mercury UV systems have been converted to LED UV to save energy. For packaging, we use paper-based gum tape instead of BOPP. We regularly apply lean manufacturing principles to reduce waste and improve efficiency.

Manoj Kochar Holoflex Kolkata: We conducted an audit of our electrical efficiency and brought about changes. As a result of this we saved about 15% energy consumption. We have invested in new energy efficient and automated machines to produce finished labels with highly reduced wastages.

Mahendra Shah Renault Paper Palghar: Our Investments in fully servo auto register press have enabled us to produce with less wastage and improved efficiency. We invested in a semi rotary press for short runs, new job proofing , base coats  and overprint varnishes for complex short runs without much wastage of material and energy. Having color matching systems offline to save press time and electricity as well. We try to use more recycled material or green material. Investment in an ink kitchen is in the process of cutting down on ink wastages. We send our waste matrix and trim waste etc. to certified recyclers.

Himanshu Kapur, JK Fine Print Mumbai: We have tied up with an NGO for recycling trims, waste matrix and other production label waste. All other waste material goes to a cement plant for generation of energy via a catalytic converter. Wastewater is treated completely before discharge. We promote wash off labels. We are in the process of converting UV drying to LED to conserve electricity.

All UV lamps are ethically disposed with mercury separated. We are planning to promote rPet as a liner to replace glassine liners.

B K Manjunath Global Printing and Packaging Bengaluru: One of our key sustainability initiatives is the installation of solar panels on our rooftop to harness renewable energy meeting 40% of our energy consumption. We invested in advanced waste management systems, including a Sewage Treatment Plant (STP) and Effluent Treatment Plant (ETP) with a combined capacity of 10 KLD (Kilo Liters per Day). This facility ensures that all wastewater generated during operations is treated and disposed in an environmentally responsible manner. We have a rainwater harvesting system with a capacity of 1 lakh liters, supporting water conservation. We are FSC® (Forest Stewardship Council®) Certified, enabling us to supply cartons, labels, and leaflets made from responsibly sourced materials. 

Rajeev Nair Stallion Systems, Kochi: In our endeavor to be a sustainable producer, we have switched over to LED to reduce power consumption. Investment is made in new faster converting equipment with increased width to produce bigger volumes efficiently with reduced wastages. We have initiated the usage of thinner liners to reduce material usage. We now source our requirement of thermal transfer ribbons from manufacturers who are fully compliant to European Standards despite the products being priced higher. We are in the process of getting our EPR registration completed. 

It is a good sign that our label converters have understood the imperative need for sustainability are taking measures to implement. Though these are initial endeavors and much more needs to be done . It is hoped that industry at large will recognize the need to leave behind a safer planet for the generations that follow. 

Written by Harveer Sahni, Chairman Weldon Celloplast Limited New Delhi April 2025

Environmentally conscious and sustainable in labels

Another day in life many years ago, we would love to light up a bonfire on a winter evening and sit around it warming ourselves and enjoying it. It was a common sight to see construction workers and other labourers huddled around a small fire they would light up by burning tree branches or dried leaves to warm themselves and ward off the cold. This incineration, which was a pleasurable exercise once, is looked at as non-acceptable now because it generates smoke and adds to the already high level of pollution in our cities. In the 1960s all our groceries were shopped wrapped in paper or carried in paper bags. In India we saw a lot of paper bags made even from old newspapers and old magazines adding an element of recyclability to the already used paper. 

In 1965 Swedish company Celloplast patented the single use poly bag to start an era of convenience in shopping with plastic bags. By late 1970s or early 1980s the polybag evolution had reached India and started to grow at a robust pace. It also became the preferred packaging material for a very diverse range of end products. Rapid developments were made to create multipolymer laminates to achieve better shelf life and barrier properties.   So much so that it became difficult to imagine a life without these plastic bags.

Mountain of garbage termed as landfil

Ironically by end of the last century the ill effects of plastic waste due to non-biodegradability became the most worrying factor for governments. The plastic bags littered around the globe remained plastic for years and would remain so for hundreds of years. Bangladesh became the first country in the world to implement a ban on thin plastic bags, after it was found they played a key role in clogging drainage systems during disastrous flooding. Other countries began to follow suit. Soon the awareness came about that plastic was not only clogging drains but also adding to soil quality erosion, affecting life of cattle who devoured these while grazing and endangered the sea with tons of plastic dumped in. The heightened awareness of all kinds of waste going to landfills; in fact, they are no more landfills but have become garbage mountains occupying expensive and already shrinking land space in cities and emitting poisonous gasses impacting environment and health of population. Climate control, banning single use plastics, finding alternative to multi-polymer plastic laminates due to these not being recycled, conserving resources, recycling, reusing, waste management, etc. became imperatives for all governments. Environmental protection and sustainability became the necessity and buzzword for a safe future of generations that follow us. Sustainability is explained as the avoidance of depletion of natural resources in order to maintain an ecological balance, in other words replenishing the mother earth with the natural resources that we use for our benefits.

Kimoha Solar plant

The author while returning from Labelexpo Europe in Brussels in the end of September 2019, stopped over to visit Dubai based label printing company Kimoha. While excelling in the world of labels Kimoha leadership had done a lot of work including investing for environmental protection, waste management and sustainability, setting example for others in the label industry to follow suit. Being fully aware that advancements and enhancement approaches are needed for the economic development of the present without compromising the capacity of future generations, Kimoha has taken steps to be sustainable and take care of the environment and its social well-being. They successfully completed the Green Building Initiative and are the first printing company within GCC to have the Gold LEED certification from the US GBC for its manufacturing facility. Under the new green clean energy initiative, they have commissioned own Solar Plant with Installed capacity of 1.0143 MWp, generating 30% of their power requirement. Kimoha Solar Plant is one of the largest Solar plant in the manufacturing segment within JAFZA. All the mechanical material handling systems are battery operated to cut off use of fuel and its associated pollution.

Integrated Waste Management System

Kimoha sources material from FSC certified partners as a responsible management initiative in protecting forests, being in paper industry.  The entire facility light management system is based on Motion & Occupancy Sensors. Occupancy sensors increase lighting energy savings by 23 %, auto turning off or turning down for amount of time with no movement. Skylights are used as natural lights here at Kimoha warehouse, thus further adding to Energy Management initiatives. As a part of its water conservation initiative, waterless urinals are installed in the facility washrooms. One waterless urinal saves approximately 3,250 gallons of water a year. The Solar cleaning system is also of dry wash robotic system which aids this program. On its Carbon footprint initiative, Kimoha has installed a state of art Integrated Waste Management System for auto extracting and compacting its label design and trim waste. Most of the paper waste is bailed, to reduce size and skip loads and sent to recycling vendors for a circular economy. Right from inception Kimoha has always believed in human capital and thus refrained from using Solvent Inks.  Kimoha also has a Sedex Member Mark which is a testimony to their responsible and sustainable business practices.

Back home in India the author tried to touch base with label printers in India to understand if they too were investing to make their industry and products environmentally safe and sustainable. It was heartening to note that the process has begun but it is just the beginning. To have a large-scale impact down the line, it appears legislation will provide the necessary impetus required in this direction. Noida based Any Graphics lead by Kuldip Goel is building a new huge new certified green factory spread over 15500 square meters that will be ready to move into in 2020. Kuldip Goel says: ‘The green manufacturing unit will be our contribution towards being environment friendly and sustainable. The process began right from the time when we started building the plant. For instance, we cannot uproot any trees from the new land without having a plan to re-plant and nurture them and plant maximum number of local varieties.’ Complying to the Green factory requirements they are procuring maximum construction materials produced from within 500 kms of the construction site, using minimum 50 percent old material and furniture from previous factory, minimum usage of wood, covered car parking, usage of less water and big fume taps to save water, natural sunlight inside the factory, usage of light and insulating Autoclaved Aerated Concrete (AAC) panels in the building, amongst others. They also plan to install both sewage treatment plant (STP) as well as an effluent treatment plant (ETP) at the new facility. ‘With the STP, they will be able to re-use almost 50 percent of our water that would otherwise just go down the drains. With the consumption of almost 40,000 litres of water a day, this will be a huge saving. They are also installing state of the art 600-700 KW rooftop solar power units. This will reduce 5.5 to 7.5 MT of CO2 emissions annually, equivalent to planting about 35,000 trees. Goel further added, “We have even studied air direction at the new site to maximize the impact of air flow and sun for most efficient use of solar light and energy. There is a list of above 40 requirements listed by The Indian Green Building Council (IGBC) that we must adhere to for our factory to be qualified as a green building and we are passionately working on each one of them”.

The author with Anuj Bhargava

Another Noida based Label Company Anuj Bhargava lead Kumar Labels who also produce labelstock for their captive consumption has put in place many processes in their production plan to make their contribution to environment and sustainability. They have shifted to 100% LED lighting in their factory. They plan to replace UV lams with LED UV lamps on all their presses by 2021, the process has begun. They have developed and commercialized SRTF (Single Release with Two Face stocks) which saves 50% release liner. Spreading the concept globally. Other endeavors include elimination of corrugated boxes and using multi-use plastic trays for dispatches within 200km distance which saved over 15 Tons of kraft each year. Selling labels on bagasse, mineral paper and recycled kraft label stocks (though to begin with the quantity is small). Work has started to use thinner liners. 70% of factory is on evaporative cooling instead of air conditioning, saving energy. No plastic bottles or cups are used for water or food, even during group dinners. Segregation of waste is done so that most unsupported material gets recycled. Employees are encouraged to shift closer to factory to avoid commute and save fuel. To set an example, owners have also moved closer to factory. Used UV lamps are disposed off through a recycler who removes the mercury.

The self-adhesive labels industry as it continues to grow, has been facing a gigantic task for disposal of side trim, waste matrix and liner waste. Almost 50% of the label material after conversion is waste and earlier converters were either sending the same to landfill or incinerating it. Both the actions are adversely impacting the environment and require urgent attention. Multinational labelstock manufacturers Avery Dennison has taken some pioneering initiatives towards this problem. The Company under their “Avery Dennison’s Recycling Services India program” has been concerned about the accumulation of waste and is on a mission to also reduce the amount of packaging materials used beside recycling and managing the waste generated. They in association with leading brand owners started collecting the label liner generated as part of the labelling operations centrally before passing these on to the appointed recycler for this Liner Recycling Program. The collected liner waste is then reprocessed, and this recycled pulp is used to create new materials such as cardboard, paper, and tissue. On another front they are interacting with converters to co-process or reprocess their leftover label matrix instead of landfilling it at no cost, given that the paper and film materials are sorted at the converter end. The matrix that is made from either paper or film material is usually discarded. As per Avery’s initiative through co-processing, paper matrix can be re-used as fuel in industrial processes. Through reprocessing, filmic matrix is converted to polymer pellets used to manufacture products like boards and benches.

Himanshu Kapoor of Mumbai based J K Fine Prints lists the processes that they have implemented in this direction: The have started liner recycling program with Avery Dennison, all plastic ink bottles are sent to MPCB(Maharashtra Pollution Control Board) waste handling unit, used UV lamps go to hazardous waste collection unit, they pack finished rolls in paper and not in plastic, all waste is shredded and sent to cement kilns to use as an energy source to replace natural gas, cores/boxes/packing materials etc. are reused to reduce carbon footprint, waste water from water purification system is reused for cleaning purposes, all ACs/fans/lights are switched off when not in use, Auto stop taps installed resulted in reduced usage of water and collection of used liner from end users and sending to recycle in pipeline.

Sustainability is important for many reasons including environmental Quality in order to have healthy communities and a safer planet for generations that follow, we need clean air, natural resources, and a nontoxic environment. Government has now realized the huge negative impact of this and due to their efforts to spread awareness, words like sustainability, environmental protection, circular economy, recyclability, reusable, etc. have become frequently debated topics in industrial conferences and CSR initiatives of leading industrial houses. Even the common people now are impacted and concerned about this problem. Label industry has been implementing many such initiatives to reduce the impact of waste. For a lot many years we have seen press manufacturers making the label presses with short web pass to reduce setup waste, usage of thinner filmic liners have been implemented at many places to reduce the tonnage of liner going into manufacture of self-adhesive labelstock and more so because the filmic liner can be recycled to produce other plastic products. In recent times we also witness the development of linerless labels to entirely do away with the liner by use of a filmic liner that is peeled off in the manufacturing process and laminated on top of the same label. One solution cannot cater to all labelling needs, every process has its advantages and disadvantages, but the heartening fact is that now the industry is taking steps both to reduce wastage and eliminate it from going to landfills and incineration. The social responsibility of the labels industry is evident!

Written by Harveer Sahni Chairman Weldon Celloplast Limited, New Delhi December 2019

Waste matrix removal in label production

Waste matrix stripping or removal in production of self adhesive labels is a very important part of label conversion and is an imperative that leads to a web of labels which can be dispensed on automatic label dispensers in high speed packaging lines. Even though it sounds to be a simple process of stripping the ladder like extra waste after die cutting of labels, yet it remains to be one of the most complex and problematic area of label converting process. A problem with waste removal, like matrix breaking or labels lifting with the waste ladder may slow down the machine or in some cases make it extremely difficult to remove it online. Converters may have to resort to removing the waste manually offline making the process unproductive and costly. A host of parameters affect the process and it is difficult to address the issue in a singular way. With so many variables that impact the waste removal process, it is difficult to predict a simple solution. It could be due to the shape of label, size of label, release liner, face stock, adhesive, die cutting process, speed of conversion, die blades or the design of the waste removal section that may affect the correct and efficient removal at the optimum machine speed. Any of these may impact the final result and slow down the machine and the printing process. No one solution can apply to all problems. The traditional waste rewinding system is gradually becoming unpopular due the fact that tension is the key to efficient waste rewind. The rewound waste matrix ladder roll has empty spaces from where labels have been die-cut and as the roll becomes bigger there is lot of irregular tensions leading to breaks. As the market becomes extremely competitive with rising prices of labelstocks printers tend to reduce the gap between the labels to 2mm making the process even more difficult. This article will dwell on most of the variables mentioned here above.

Release Liners: The most widely used base papers as release liners in self adhesive label materials are glassine, super calendared Kraft and clay coated Kraft. These are uniform caliper, densified and non porous papers that have adequate strength and accept a uniform coating of silicone giving excellent releasing properties to become a proper backing for self adhesive papers. In recent years due to possibility of recycling and reducing the tonnage of waste generated, filmic liners also are being used as backing in labels. Release liners play a major role in die cutting and in turn impact the waste removal process. The die blade has to cut through the laminate and stop at the face of the liner so has to achieve a perfect half cut or kiss cut. The uniform thickness or caliper of the liner is an imperative. If the liner has variations, it will create problems at die cutting and eventually at waste stripping. If the release gets thicker the die will pierce the liner making a through cut and exposing paper fibers to the adhesive.  This also may result in web breaks. If the liner gets thinner, the die will not cut resulting in labels lifting with the matrix. Release level of the liner is also very important. If the release level is tight the matrix will tend to break due to tension and if it is too easy, labels will tend to lift with the ladder. Uneven silicone coating or pinholes in coating may also create problems. If the labelstock prior to waste matrix removal goes through a nip roll that has excessive pressure between them, the edges may develop micronic nicks that may render the face paper susceptible to web breaks. The paper rolls may also develop these rough edges in transportation and mishandling. The web needs to be inspected thoroughly before taking up label conversion.

 Face Paper:  Paper and films are generally used as face materials. A fairly high strength paper will perform well if all other parameters are addressed. If the gap in labels is too small, 2mm or less, the matrix will tend to break repeatedly. Moisture content in paper should ideally be between 3.5% and 5.5%; sharp increase in moisture will affect the strength adversely. The tensile strength of paper at Relative Humidity (RH) up to 50% is maximum after which it moderately decreases with RH up to 65% and on further increase in RH, it drops sharply. The uncoated papers are hygroscopic, so they tend to absorb moisture faster than coated papers. Evidently weather and storage condition of paper does have an impact on waste removal. Even when using emulsion based adhesive if the adhesive is not dried properly, the face paper will tend to absorb the residual moisture from the adhesive and result in deterioration of paper and affect waste stripping. In case of filmic face stocks, weather may not impact but the condition of die and quality of die cutting does play a major role. If the die is damaged or blunt it may not cut properly resulting in label lifting or film tear.

Adhesive: Commonly available labelstocks are coated with either emulsion based or hot melt pressure sensitive adhesives (HMPSA). In both cases for a perfect waste removal it is necessary that the die cuts through the adhesive as well, as otherwise if the coated film of adhesive is not cut, labels will lift with the matrix. Emulsion adhesives have good die cut ability however hot melt adhesives for better die cutting properties have to be specially selected. In case of HMPSA if the waste is not lifted immediately after die cutting the adhesive may rejoin and lift the labels with the matrix.

Size and shape of a label: These are parameters that are customer driven based on their specific needs, so the converting company cannot request changes from customer.  Small labels have a very limited area of contact and reduced tack holding it to the release liner and with little force the label may fly off or lift off with the matrix. In such a case die makers suggest packing self adhesive foam in the die shapes so as to push the label back on the release liner. Other times printers have found limited success in addressing this problem by increasing speed of the web. Waste ladder removal of irregular and complex shaped labels with sharp corners like in a star shape, is even more complex to handle. This becomes even more difficult in substrates like BOPP where a small nick may lead to web break. Converters need to slow down the machine to a great extent to finish the labels online. Machine manufacturers have addressed this issue of handling complex shapes as explained later in this article.

Die design: The die has a definite role to play in waste matrix removal. The subject is extensive and can take a full article to dwell on the nuances. The blade angle, blade height and coating on the die are factors that lead to ease or difficulty of label conversion.  Thickness of the face materials, type of adhesive and thickness of release liners are all imperative inputs that are needed before a die is put into production. A die that is designed for paper material is not recommended for filmic materials. Blade angle for paper is kept wider so that after penetration of around 80% into the paper the rest of the cut happens by crush or bursting of the material before stopping at the surface of the liner. In case of filmic face material a sharper acute angle is needed to pierce the film as in case of a wider angle the film will stretch and not be cut. An acute angle blade appears to cut better but wears off faster than the wider angle blade dies. Depending on the materials used the die angle varies between 45degrees and 110 degrees. The blade height needs to be adjusted to cut through the face, which maybe paper or film or a laminate, and adhesive without piercing the release liner. If any of the parameters is not right, the waste matrix removal will become a challenge. If the blade pierces the liner even slightly, it may expose the release paper fibers to the adhesive and get stuck to them causing waste ladder breakage. If the blade does not cut through the adhesive, labels will lift with the matrix. In case of coated materials like direct thermal and thermal transfer the coatings on the paper are abrasive in nature and tend to make the die wear off soon. In such case laser hardened dies are recommended. Adhesive sticking and building up on the dies also results in uneven cutting and also resulting in early die wear off. This is more evident where aggressive high tack hot melt adhesives are used. For this reason special non stick, coated dies are available so that the adhesive will not stick to them. The standard gap between the magnetic cylinder and the anvil is also very important as in case of die wear off the gap increases resulting in spaces where labels are not cut and would lift off with the matrix and to get a perfect cut the die pressure is increased. This results in faster wearing off of the bearers leading to a smaller gap and over cutting. Care has to be taken in die storage and handling. Before commencing any job proper inspection of die should be done regarding cleaner blades, blunt edges or nicks. The dies need to be stored in an environment avoiding excess humidity which may result in rusting.

Machine manufacturers have been consistently making efforts to address the issue of waste matrix removal to aid faster converting. Some of the steps taken include; 1.Lifting the waste matrix immediately after die-cutting. 2. Taking the die to a larger diameter stripping roller that would support the waste ladder on separation rather than a thin diameter roll that would provide a sharp angle to waste being stripped off. 3. By rethreading the paper in such a manner that the label web is peeled off the matrix instead of the matrix being pulled off. 4. De-laminating the web and re-laminating it before die cutting as this would reduce the tension required to peel off. These measures did help to some extent but complex shapes and a host of issues and factors that impact this process have had machine manufacturers continuously researching this area to keep implementing changes. One such solution that came around some years back was suction of the waste matrix into a suction and shredding system. This does take care of the tension and also manages waste by cutting it to small pieces and compacting it, but such systems have other problems. They are expensive, large in size so difficult to be fitted on presses due to lack of space, costly to operate as they use extra motors, compressor or vacuum and very noisy to run. Yet there is a brighter side to it, there is development going on to separate the waste and recycle it inline so as to reduce the impact on environment.

The larger established press manufacturers seem to have reached a viable solution. Some years ago they have introduced a big innovation in the industry by designing a simpler contact system rewinder for waste matrix. The idea was very simple; instead of pulling only the matrix up to the rewinder, we pull the entire web up near the rewinder. Here the matrix is peeled off against an idle roll and immediately pasted on the rewinder. Basically this reduces the travel of the matrix from 1 meter to hardly 5 cm and the journey is even supported by a roll. This system has now become the standard with many label press manufacturers

“Simple solutions are invented to simplify the label converting process however It does not hold true for all jobs, when a problem comes it can be challenging and creating a solution can be another game changer”!

Written by Harveer Sahni Chairman Weldon Celloplast Limited New Delhi January 2018

NOTE: This article is exclusively written for magazine Label and Narrow Web USA. Publications desirous of reproducing the article may write for permission to Steve Katz editor LNW : skatz@rodmanmedia.com