新闻中心
The spine of a round spine hardcover book is curved, and when opened, the book core bends along the curved surface. The adhesive layer needs to have good flexibility and resilience. Hard rubber particles have high adhesive strength but are prone to cracking when bent, while soft rubber particles are flexible but have insufficient adhesive strength – selection requires finding a balance between strength and flexibility.
| Comparison item | Soft rubber particles (low softening point) | Hard rubber particles (high softening point) |
|---|---|---|
| softening point | 65-80°C | 85-100°C |
| Bending rebound | Excellent, 180 ° repeated bending without cracks | Medium, visible fine lines after bending 3-5 times |
| peel strength | 2.5-3.5 N/cm | 4.0-5.5 N/cm |
| Circular spine retention force | Okay, the arc won’t bounce back naturally | Generally, the spine of the book tends to rebound and flatten |
| Applicable scenarios | Round spine hardcover, picture book, art book | Fangji hardcover, reference book |
Round spine hardcover is recommended with soft rubber particles or medium soft type – with sufficient adhesion, worry free bending, and stable curved shape. Recommended for square spine hardcover or thick reference books are hard rubber particles – with priority given to strength and better load-bearing capacity. Both types of Sunlife hot melt adhesive have corresponding models, and Guangzhou Sunlife Trading can recommend them for free based on spine thickness and binding method.
Hot melt adhesive granulesHow to read the test report? Legitimate hot melt adhesive particles should come with a testing report when leaving the factory. Newcomers are often discouraged by a bunch of indicators, but in fact, by grasping a few key items, one can judge whether it is good or bad. Below is a comparison […]
General conclusion:Standard spot models can be shipped within 1-3 days, non-standard customized or color matching models within 7-15 days, and export orders with third-party testing reports within 15-25 days.But this is just an ideal state, what really determines when you can turn on is the following 8 factors. By checking them one by one, the […]
Conclusion first: Factories with large daily shipments and automated production lines have lower comprehensive costs and better anti disassembly properties for sealing boxes with hot melt adhesive particles; For businesses that focus on small batches and manual packaging, adhesive tape is more flexible. The watershed is roughly 500 boxes per day – beyond this amount, […]
In the field of book binding, EVA flat hot melt adhesive has become the preferred adhesive for high-frequency flipping paper products such as picture books, notebooks, and test papers due to its core advantages of perfect 180 ° flat spreading and flexible and folding resistant spine. As a high-tech enterprise deeply involved in the hot […]
