Perfect Binding: Traditional vs PUR Glue - Which Method is Right for Your Book?

Perfect binding is one of the most popular methods for creating professional-looking books, magazines, and catalogues. It’s what you picture when you think about your typical softcover/paperback novel or expect to see on magazine stands at the local supermarket. It’s only natural that most people that books with this type of binding are all made the same but in fact, the glue used in this binding can vary. 

The main contenders are typically the traditional hot-melt adhesive often referred to as EVA glue and the newer, recommended PUR (Polyurethane Reactive) glue. Many publishers and print shops find themselves weighing the pros and cons. Understanding the differences between these two glue options for perfect binding might help you give you a better idea of what is involved in creating books using this method. 

What is Perfect Binding?

Before we get too into the glue of things, let’s first clarify what perfect binding is. 

Perfect binding is a bookbinding technique where pages are glued together at the spine and then attached to a cover. It’s that simple! Unlike saddle-stitching or spiral binding, perfect binding creates a flat, square spine that's ideal for displaying titles and author names. This is why it’s the most common method for paperback books, magazines, catalogues, thicker booklets and corporate documents like annual reports.

Traditional Perfect Binding: The Time-Tested Method

Traditional perfect binding uses the aforementioned hot-melt adhesive, typically EVA (Ethylene Vinyl Acetate) based glue. The process involves heating the adhesive to around 175°C (350°F) (hence the common name of hot melt glue), applying it to the spine of the book block, and then attaching the cover while the glue is still hot and pliable.

Advantages of Traditional Binding

• Cost-effective: Hot-melt adhesives are generally less expensive than PUR alternatives.
• Fast production: Quick setup and faster cure times can result in a higher output of books, and therefore a shorter turnaround time.
• Widely available: Many print shops are equipped with perfect binding equipment that is compatible with hot melt glue.
• Proven reliability: Decades of successful use in the industry.
• Easy troubleshooting: Well-understood process with established best practices

Limitations

• Temperature sensitivity: Books may fail in extreme heat or cold conditions, which isn’t ideal when it can get quite hot in Australia. 
• Limited flexibility: Pages can crack when books are opened up or with heavy use, causing the glue to separate and lose integrity.
• Shorter lifespan: Adhesive may become brittle over time, making these books not as long lasting.
• Substrate restrictions: This type of glue works best with specific paper types and weights, making it harder to bind books with unique papers and materials.

PUR Glue: The Modern Alternative

How It Works

PUR (Polyurethane Reactive) glue is a “moisture-curing” adhesive that chemically bonds with the paper fibers. Unlike the traditional EVA glue, it’s applied at lower temperatures (around 120°C/250°F), and gets its moisture-curing label because it reacts with humidity in the air to form a flexible, durable bond that actually penetrates the paper rather than just adhering to the surface.

Advantages of PUR Binding

• Superior durability: Books bound with PUR can withstand repeated opening and closing without the spines cracking or falling apart. 
• Temperature resistance: The fact that it doesn’t need to be applied when it’s really hot, means it can survive more extreme temperature conditions
• Flexibility: Allows books to lay flat when opened without the spine cracking
• Versatile substrate compatibility: It works with coated papers, plastics, and other challenging materials that may not be as durable with a traditional adhesive. 
• Stronger bond: PUR glue penetrating the paper itself, means it’s three to four times stronger than hot-melt glue, providing you with much more durability in the long term.
• Professional finish: You’re less likely to see any glue squeeze out that might occur at the top or bottom of the spine, for a much cleaner appearance. 

Limitations

• Higher cost: PUR adhesive is slightly more expensive than traditional hot-melt glue, which is a typical limitation for a higher quality end-product.
• Slower production: It takes a bit longer for each book to cure, which can add to the production time for big print runs.

Key Similarities Between Both Methods

Despite their differences, traditional and PUR perfect binding share several important characteristics:

Production Process: Both methods follow the same basic workflow - gathering pages, milling the spine, applying adhesive, and attaching the cover.

Final Appearance: When properly executed, both methods produce professional-looking books with clean, square spines suitable for retail display.

Quality Standards: Both can achieve high-quality results when proper techniques and materials are used.

Which Method is Best?

If you had to choose one, it would be perfect binding with PUR glue. Yes, we’re biased as we perfect bind all our books with it, but on paper, it’s also objectively the best as its benefits, easily outway any limitations. 

Books bound with PUR glue are more durable and the most cost-effective book binding option, second to case-binding (hardcover) for ensuring that your book has longevity even when it is being used repeatedly. This method provides greater flexibility for paper stocks and at the end of the day, it’s able to produce books with the same, professional finish as a traditionally perfect bound book. Traditional perfect binding may be the best option for you if you have a very high-volume print run and limited time for production, but in almost any other case, we think PUR glue is the winner. 

Making the Right Choice for Your Project

The decision between traditional and PUR perfect binding ultimately depends on your specific needs, budget, and quality requirements. Consider factors such as the intended use of the book, distribution environment, target audience, and how long you’d expect a copy to last. Both traditional and PUR perfect binding are both actively used and have their place in modern book production, but it comes at no surprise to us of the increasing popularity of using PUR over traditional hot melt adhesive in recent years. 

Whether you choose the proven reliability of traditional binding or the advanced performance of PUR, proper execution and quality materials used by your selected printer are the foundations to producing great, professional-looking books. We hope this article has helped you learn a bit more about perfect binding and how it has evolved, to give you some confidence when approaching your next book printing project. 

Looking to produce your next book project and keen to choose perfect binding with PUR glue? Get in touch today and one of our printing experts will reach out for a personalised consultation based on your specific requirements.