What should I do if the glue breaks when flipping pages in a book? Explain everything from the cause to the solution in one go

Direct answer: The reason for the broken glue when flipping pages in the adhesive book is that the glue layer has not penetrated into the back of the book and the glue layer is brittle. The solution needs to start from four aspects – milling and slotting should be in place, the temperature and amount of glue should be appropriate, the special glue particles for books and periodicals with good toughness should be selected, and the pressing and shaping should be sufficient. After adjusting item by item, page flipping and glue breakage can be basically eliminated.

Why do the pages turn and the glue breaks

Wireless adhesive binding relies on the infiltration of adhesive solution into the back milling groove of the book, holding onto every inner page. If the milling back is too shallow or no rough surface is milled out, the adhesive only floats on the surface and will detach as a whole when turned over; If the adhesive layer is too brittle (due to high temperature oxidation or poor toughness of the adhesive particles), repeated folding will cause it to crack along the back of the book. The most common complaints that Guangzhou Sunlife Trading handles regarding broken adhesive are inadequate milling and aging of the adhesive layer.

Four step solution

• Milling back slottingMilling the back to a depth of 1-1.5 millimeters and milling out the rough surface to create a bite surface for the adhesive solution; If the knife becomes dull, replace it in time;
• Temperature and Glue QuantityAccording to the recommended temperature setting for adhesive particles, the thickness of the adhesive layer should be 0.6-1 millimeters. If it is too thin, it cannot be held tightly, and if it is too thick, it is prone to brittleness;
• Select the right adhesive particlesSelect EVA adhesive particles with good toughness and folding resistance for books and periodicals, and provide specialized models for copperplate paper and thin paper;
• Fully press togetherThe clamping and shaping time is sufficient to allow the adhesive to fully penetrate before cooling to form a film.

Different types of paper should be treated differently

Frequently Asked Questions

Q: Can the already bound book be repaired if the glue breaks?
Small batches can be partially repaired with adhesive and back pressure, but the root cause still requires adjusting the milling back, temperature, and adhesive particle selection correctly in the production process, and the rework cost is much higher than doing it well in one go.

Q: Does it necessarily mean that the rubber particles with better toughness will continue to be glued?
Replacing the right adhesive particles is an important step, but if the milling and pressing are not in place, even the best adhesive will be useless. All four items need to be done together.

Summary: Page flipping and adhesive breakage are jointly determined by “process+adhesive particles”. With proper milling, appropriate temperature, selection of the right tough adhesive, and sufficient compression, all four steps can be taken to cure the problem. Sunlife hot melt adhesive provides specialized series for books and periodicals, as well as on-site diagnostic support.