What You Need to Know about Adhesive Systems for Mailings and Postal Packaging

The United States Postal Service has specific guidelines for folded mailers that must be followed by commercial senders. These standards, designed to prevent mailers from opening at the edges and jamming high-speed mail processing equipment, dictate that all folded mailers must be attached at three points. The traditional approach to doing this has been to use wafer seals that wrap around the edge of the material, a technique known as tabbing. However, tabbing with wafer seals is slow, costly and inconvenient, but fortunately, better options exist for sealing your mailers in accordance with the Postal Service’s regulations.

The Problems with Tabbing with Wafer Seals

While tabbing using wafer seals is the most popular method of sealing folded mailers, it’s certainly not the best option. Why not? Tabbing poses a number of serious issues, including:

  • It’s slow: When compared to other methods, tabbing with wafer seals is downright slow. Using wafer seals, you can process about 1,000 to 2,000 mailers per hour. That might sound like a lot, but consider that tabbing with fugitive hot melt (glue) allows you to process between 5,000 to 10,000 mailers per hour. That’s up to 10 times faster than using wafer seals!
  • It’s costly: The cost of using wafer seals can add up quickly. At one cent each, wafer seals are a much costlier choice than other sealing options. For example, using a hot melt gluing system costs just 1/5 of one cent for each mailer.
  • It’s not user-friendly: Consumers hate opening tabbed mailers. They’re a hassle to open, and often times, the mailer can get torn and damaged as the recipient struggles to get it open. Needless to say, this lack of user-friendliness doesn’t help mailers achieve their goals. Folded mailers that use a glue adhesive are typically much easier to open.

Choosing the Right Adhesive System for Your Folded Mailers

Clearly, the advantages of using a hot melt tab gluing system far outweigh those of using wafer seals. But how can you make sure you select the right hot melt adhesive system for your needs? With so many options available, it’s important that you choose a machine that comes from a manufacturer known for producing quality, efficient equipment at fair prices.

Glue Machinery Corporation has been providing world-class hot melt machinery for over 50 years, servicing some of the world’s biggest corporations. With a range of adhesive equipment ideal for fast processing of mailers, including the GIA1075, Hot Melt Tab Gluer Retrofit, and Buckle Folder Hot Melt Gluer Package, Glue Machinery Corporation has the right adhesive system to match your unique needs.


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