How to check for glue cracking in graphic and text fast printing binding? Key points for using hot melt adhesive and checking rush orders

The two things that are most feared in bid binding are flipping pages and opening glue, and cracking the spine of the book. The solution is to chooseGood flexibility, opening time 6-10; s、 Softening point 85; Up and down in ℃ofHot melt adhesive granulesCooperate with moderate back milling and sufficient clamping time. The bidding documents are mostly 80%; G double adhesive paper with colored separators, uneven paper thickness and large surface differences, relying on; Apply more glue&# 8221; It can’t be suppressed.

Why is it easy to flip pages and open glue when binding bidding documents

A bidding document is a dynamic that requires extensive and detailed reading, and page loss is rarely a single reason. The three common causes are:

• Insufficient penetration.The viscosity of the adhesive is too high or the operating temperature is too low. The adhesive only sticks to the surface of the book back and does not “bite” into the paper fibers. It will detach from the interface with a slight flip.
• The milling back is not in place.The milling back is too shallow, the paper fibers are not exposed enough, and the adhesive lacks a surface that can be interlocked.
• Insufficient clamping time.During rush work, the clamping time is compressed, and the glue enters the cutting process before it is fully formed, resulting in weak interface bonding.

Three steps of on-site diagnosis

• Look at the cross-section.Tearing open the spine of the book, if the adhesive peels off in a shell like manner, it indicates insufficient penetration – often due to high viscosity or low temperature.
• Look at the milling back.Check if the milling depth and cutting edge are sharp; When the fiber exposure is insufficient, priority should be given to adjusting the milling back.
• Look at the clamping.Check if the clamping time has been compressed below the process requirements.

Parameter reference (fine tuned by live parts)

The following table shows common reference values for tender documents, which need to be calculated based on paper, page count, and equipmentFirst, make a sample to confirm：

For scenarios such as quick printing of graphics and text, and binding of bidding documents with “multiple varieties, multiple papers, and tight delivery times”, it is recommended to keep a well adapted one on handSpecialized adhesive for graphic and text storesWhen encountering mixed paper, make a sample first and then measure it.

Four Reminders for Colleagues

• The bidding document is; Read extensively and read in detail; Flexibility is more important than simple high strength in living things.
• Mixed paper (copperplate spacer+double adhesive text) must be sampled first, do not use conventional live parts parameters to rigidly fit.
• The last thing to compress during rush work is the clamping time, which directly determines whether the glue will crack or not.
• Keeping a dedicated adhesive granule for books and periodicals is much more secure than borrowing materials from various sources at the last minute.

Frequently Asked Questions (FAQ)

Q: The number of pages in the bid is not many. Can we use staples and seals?
Answer: Some bidding documents explicitly require that the adhesive cannot be disassembled or replaced, and it is necessary to read the binding terms of the bidding documents before bidding.

Q: Is it better to mill deeper back?
Answer: No. Too deep will weaken the paper connection strength, usually 0.8-1.2; Mm is sufficient, fine tune according to the paper and page number.

Guangzhou Sunlife Trading provides small package sizes of Sunlife hot melt adhesive for graphic and text fast printing stores. It supports sampling before placing an order and can provide recommended process parameters for different types of products such as bidding documents, brochures, and manuals.