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Why environmentally benign adhesives?



Published September 8, 2005
Related Searches: Label printer Pressure sensitive TLMI
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The first and simplest answer is, of course, that I write under the name "Letters from the Earth."  (Has anyone figured that out?)! Second, most of us are from the industry and are pretty familiar with adhesives.  At least we think we are.  So, what do benign adhesives have to do with our business? We know the general categories of adhesives and which adhesives work with which substrate. In fact, many of us probably have a favorite adhesive from a favorite supplier. It processes well, it sticks well, it doesn't smell (much), it doesn't ooze, it's cheap, and so on.

Then what's missing?

It seems to me that what's missing is that none of the above helps build or contribute to an "eco-economy." Yes, back to Lester Brown. All of you, including our trade press authors, miss one incredibly important point. None of these pressure sensitive adhesives is environmentally friendly. I've said several times that I'm not a tree hugger. But what drives me crazy is an apparent disregard for the environmental impact that a technology can have on our environment. I am looking for environmental balance. I am striving for an eco-environment. Pressure sensitive adhesives, as formulated today, do not contribute to an eco-environment. I want to make pressure sensitive adhesives and labeling competitive environmentally with other identification technologies. I want to encourage liner recycling and the use of benign adhesives. I want to celebrate the virtues of pressure sensitive labels by understanding and using, whenever possible, practical, and economically viable, environmentally benign adhesives (EBAs).

A little history: The typical PSA glue contaminates paper and film. We've created adhesive formulations that work as described earlier without any regard to their after-life. In other words, once we have married a typical PSA adhesive to paper and/or film we have eliminated any possibility for recycling. PSAs contaminate papers and films. For years the paper industry has recognized PSAs as a major problem in recycling. These glues cause "stickies" when found in secondary fiber. Indeed, today there is enormous controversy regarding the value of sorted office paper (SOP) a common waste paper grade. If a paper machine is shut down because of contamination from PSAs found in SOP it has little, if any, value at all.

"Stickies" clog and "foul process equipment used in the paper making process," wrote Richard Oldack in a recent issue of The Illuminator, TLMI's member publication. This kind of contamination costs the paper industry upwards of one billion dollars a year. Oldack, president of Dyna-Tech, said that traditional PSAs "create defects in high quality office papers." In his article, "Solving a 'Sticky' Issue", he described the past and present of PSAs and how they affect paper manufacturing. Very simply, most paper and tissue manufacturers cannot dispense traditional adhesives. They clog screens and eventually contaminate, causing rejects, downtime, and loss of product.

As time has gone on, the use of pressure sensitive label stocks increased and the issue of stickies increased. While cleaning and screening by the paper manufacturer has improved dramatically, it has not been able to keep pace with the development and increased volumes of PSA.

As we began the 1990s, the debate between paper manufacturers and label printers raged. It became virtually impossible for a waste supplier to guarantee that his stock would be PSA label free. Contamination in sorted office waste was normal.

But something dramatic occurred in the mid 1990s. The United States Postal Service, with a unique action, formed a board made up of both government and private industry sectors to develop adhesives for the pressure sensitive stamp that could be recycled. The technology had existed but never been defined by trials, specifications, and the like. This development board worked to:

  • define EBA for stamps and paper label products;
  • develop laboratory protocol;
  • conduct pulp mill trials with EBA stamp product;
  • develop specifications for acceptable levels of contaminants in SOP; and
  • identify qualified EBAs.
  •  

This made sense. After all, the PSA stamp is a highly visible label application. We'd moved from water activated glue to PSA. The US government was on a "green kick", and certainly it would be incongruous to create anything that was not green, hence, EBA. This is a significant development. First of all, the pressure sensitive postage stamp represents 50,000,000,000 MSI/year in volume. Second, envelopes with stamps became recyclable.

It would be very nice if we could just take the EBA technology from the stamp application and transfer it to all general label stock adhesives. But it's not so simple. There is enormous complexity around the use of EBAs. The laminate manufacturers have the Olympian task of creating EBAs that work under a variety of conditions with a variety of substrates. Some laminate manufacturers ask, "Is the exercise worth it?" Industries generate by-product, so why worry about it? Others say EBAs will cost more money and customers won't pay more. Finally, the legal implications are mind-boggling because EBAs were developed for the PSA stamp. Using EBAs in other applications is uncharted water.

To those I would only point out:

  • We need to promote and stimulate recycling and the use of "green" products in any way possible.
  • Neither the government nor private industry is going to pay more. Look at Wal-Mart and RFID. Suppliers must be RFID compliant at no additional cost to Wal-Mart. The same is true of EBAs: The buyer must demand EBAs at no additional cost.
  • One of my colleagues, Fred Gustafson of 3M, looked up the history of recycled fiber content in government purchased copy paper. It has taken 3 Executive Orders and 15 years, but today US government employees are supposed to buy copy paper with a minimum of 30 percent recycled fiber content. The point here is that EBAs need to go through a managed process of increased use and application. No one wants to force a technology where it doesn't belong. If we can grow the use of these adhesives bit by bit we will support the use and growth of PSA label technology.
  • I realize that this is a complicated subject. What I've tried to do is whet your appetite for the possible. I know we must continue to strive to make pressure sensitive label stock and labeling a more environmentally friendly technology. The use of EBAs is a step in the right direction.

    Calvin Frost is chairman of Channeled Resources Group (CRG), headquartered in Chicago, the parent company of Maratech International and GMC Coating. His e-mail address is cfrost@channeledresources.com.


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