There are two main reasons that cause hot-melt glue to order books: "Look up at the bottom": First, the quality of hot-melt adhesives (this is the basis for the quality of bookbinding): The second is the quality of back-set processing for hot melt adhesives. Management (this is crucial). The above two factors are interrelated.
In the selection of hot melt adhesives, it is necessary to select and use hot melt adhesives with good quality and excellent cost performance. This is an effective way to ensure the quality of glue books, reduce the cost of plastics, and improve the overall economic efficiency. The "quality of the textbook" is the quality problem that arises from the performance and quality of the hot melt adhesive, which is caused by the low tensile strength and hardness of the hot melt adhesive and the low melting viscosity. The same adhesive layer thickness, different quality hot melt adhesives vary greatly.
From the process operation point of view, the existing hot melt adhesive bookbinding process book sheet is not pulled flat, once it is pulled flat (see the paper edge or adhesive layer), it will greatly reduce the page Adhesion, resulting in loose pages, page breaks. The purpose of the back milling slot is to increase the bond area of the hot melt adhesive to the page and increase its tensile (fold) strength. Therefore, the quality requirements of the milling slot must be met in the process operation. The groove depth of the back of the book (according to the situation of the paper) should be 1-1.5 mm, and the groove opening angle should be 60° (groove angle). The bookbinding machine (linear machine) is difficult to adjust due to the congenitally deficient (non-knife platen milling) and manufacturing accuracy errors. Therefore, the depth of the groove may only reach 1.2mm, which requires careful adjustment by the operator. Keeping the depth of the milling slot is the same, which is an important part of ensuring the quality of the bookbinding.
All in all, to ensure that the glue book does not loose or fall, so that the book sheet has enough tensile (fold) strength between the seams, we must use a good quality hot melt adhesive. Pay attention to the milling groove quality in the process operation, pay attention to the effect and change of the hot melt adhesive temperature on the melt viscosity so that the hot melt adhesive can reach the required paper soaking and bonding strength.
Taixing Chaobang Adhesive Co., Ltd.
