What hot melt adhesive is used for binding homework books, receipts, and exam papers? How to choose the back glue/edge glue model for printing educational materials

#What hot melt adhesive is used for binding homework books, receipts, and exam papers? How to choose the back glue/edge glue model for printing educational materials

Textbooks, receipts, and exam papers, which may appear thin, small, and simple in appearance, are actually the most prone to problems when binding: the glue may not dry during urgent orders, loose pages during cutting, and the spine of the book may be torn apart when the teacher tears open the roll. They don’t use ordinary thick book glue, but rather a quick drying, easy to tear, and non brushed one. Below, using the actual model of Sunlife, explain the selection of glue for the workbook/ticket/exam paper in one go.

1、 First of all, the conclusion is that what cultural and educational thin paper needs is not “the strongest”, but “fast drying+easy tearing+no drawing”

Thick book glue emphasizes penetration and tension, while cultural and educational materials are the opposite:

• Homework book/workbookIt should be repeatedly flipped and spread out, and the adhesive layer should not be too hard;
• Bill/DocumentIt is often necessary to tear off the secondary joint, and the adhesive should be able to “stick but cleanly tear off”;
• Exam paper/answer sheetIt is a batch urgent order, which needs to be cut and bound immediately after printing. The glue must dry quickly and cannot stick to the knife.

So the logic of choosing glue is different from thick books: prioritize readingCuring speed, initial adhesion, tear resistance, and whether it is brushed or notInstead of blindly pursuing tension.

2、 How to match back glue and edge glue

Like books and magazines, cultural and educational binding is also divided into back glue (spine body) and edge glue (side lock cover). The actual models corresponding to Sunlife are as follows:

In practical operation, common combinations are as follows: use “29A backing glue+29B edge glue” for the workbook, and “39D backing glue” for the exam paper. Report “paper type+machine speed+whether it should be easy to tear” to Sunlife, and receive a model and process card that can be landed.

3、 Key points for selecting adhesive in three common scenarios

1. Homework book, exercise book (repeatedly flipped, to be spread out)

Choose a back adhesive that is soft and has a moderate opening time (292/29A concept), and use a 298/29B locking cover for the edge adhesive. Avoid using too hard high filling adhesive, otherwise the book opening may become brittle and the pages may fall off after flipping for a long time.

2. Bills and documents (must be able to tear off duplicate copies)

The core is “able to stick but can be cleanly torn off”. Choose special files such as 29A for backing glue and 29B for edge glue. Be careful not to apply too much glue, as too thick glue may not be able to tear off completely and overflow glue may dirty the surface of the paper.

3. Exam papers and answer sheets (batch urgent orders, fast cutting)

preferred 39D This type of quick drying and easy to tear test paper adhesive solidifies quickly, does not stick to the knife, and does not scatter after cutting. With a melt adhesive window of 160-180 ℃, it is not easy for the machine speed to scatter due to the glue not drying out.

4、 On site pit avoidance

• Don’t replace it with thick book glueThick books with high filling and hard back glue, slow penetration, may not stick firmly or cut loose pages when used on thin paper.
• Don’t just apply back glue without edge glueDuring the transportation and stacking of cultural and educational materials, the side edges are the easiest to open, and the edge glue 29B/298 cannot be omitted.
• The temperature needs to be stableAdhesive glue has poor wetting below 160 ℃ and is prone to carbonization and brittleness above 180 ℃; As mentioned in Sunlife training,90% of after-sales service actually stems from equipment temperature control failureCalibrating the actual temperature of the glue pot with a thermometer is more effective than changing the glue, as it shows 160 ℃ but actually only 100 ℃.

Frequently Asked Questions

Q: Can I use regular book glue for the exam paper?

A: It can stick, but ordinary glue dries slowly and is prone to sticking to knives. When cutting urgent orders, it is easy for the pages to scatter or the spine of the book to be torn apart; 39D quick drying and easy to tear test paper glue is more compatible.

Q: Can I use the same adhesive for homework and thick books?

A: Not recommended. Homework books should be soft and easy to spread, thick books should have strong tensile strength, and the performance orientation should be different; Sunlife has divided two models based on their usage: 292/29A (cultural and educational adhesive) and 296/295/396/397 (book and magazine adhesive).

Don’t just ask ‘which one is the cheapest’ for cultural and educational printing, first distinguish whether it needs to be fast drying, easy to tear, or strong to pull. The Sunlife real model comparison above lists the adhesive on the back and edges of the workbook/ticket/test paper at once – if you can’t take it, tell Sunlife the sample book and machine speed, and match the model and process card according to the purpose, which is much more stable than testing the adhesive based on feeling.

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