In recent years, the glue-binding process has been approved by various publishers and printing houses. The bookbinding book spine has a smooth and beautiful appearance. Since iron wire is not used, iron marks cannot be seen on the cover, and it is easy to open, and it is easily accessible to books and textbooks. The stitching of the layout is beautiful. The bookbinding process has greatly shortened the book cycle. It has enabled us to bid farewell to hand-crafted processes for decades and opened up a new era of binding. However, for some printing companies that have just begun to use the glue-binding process, they often fall out. The page phenomenon, in view of this situation, talked about some of our experiences.
First, the choice of plastic
Glue is used for hot-melt adhesives, and hot-melt adhesives are used for adhesives with high tensile strength, low temperature change, high melt viscosity, high hardness, high tensile strength, and high elongation at break. At present, we have selected hot melt adhesives produced by the Shandong Provincial Academy of Sciences.
Second, milling back slot requirements
The basic requirement of milling and backing is to make the innermost page of a folded page must be milled into a single page. A page that cannot be opened by milling cannot be glued to the page. The page-dropping phenomenon after the book is inevitable. The back-milling paper should be brushed as cleanly as possible, and the brush used to brush the paper should be replaced frequently. In order to save money, some factories often use bald brushes and do not replace them. Paper hairs are brought into plastic pots, causing stickiness and stickiness. In order to solve this problem, in addition to often changing the brush, we have designed a wheeled brush that is mounted on a shaft driven by a small motor and installed behind the original brush. The direction of rotation is opposite to that of the signature. This is a secondary sweep of paper, the use of better results.
Slotting is even more critical. First look at the new slotted knife. The tip of the knife is a very sharp “∧†shape. According to our experience, it is found that the tip of the slot created by this sharp knife is too narrow, so there is a tear resistance to the page. direct impact. In order to solve this problem, we use the grinding wheel or sandpaper to gently tap the tip of the new slotted knife to make the tip rounded, so that the bottom of the slot will be like a U-shaped bottom. Relatively increased the adhesive area of ​​the glue, thus increasing the tensile force of the glue on the page, after opening the page is not easy to fall off, page off.
The groove depth we have opened is maintained between 1.2-1.6mm, and the groove angle is best at 60° so that the glue can be filled into the groove in sufficient quantity. The distance between the groove and the groove is controlled between 3-5mm. It is important to note that the rotation speed of the machine affects the groove spacing.
Third, the use of plastic
The use of glue must consider the characteristics of the gluebinder itself. There are pre-melting pots that must be strictly in accordance with the pre-melting method. For example, the Shanghai Unisplendour disc packer has a pre-melting pot, and the glue must be added to the pre-flushing pot. After the temperature reaches the standard, pour it into a plastic pot. Do not add dry glue directly to the pot. Because the plastic pot itself is small, adding dry glue will directly cause the temperature of the glue to drop, making the plastic brittle and cracked and shelling off, thus causing page breaks. Germany's Warrenbeg perfecting machine does not have a pre-melting pot, which requires the operator to add dry glue, one time can not be added too much, so as not to affect the glue temperature, to do less and ground. The temperature of the general glue should be maintained at 170°C, and the glue pan and glue tank should be cleaned at least once a month to prevent the aged glue from being incorporated therein. For the temperature of the glue, do not rely on the automatic temperature measurement of the machine. It is better to use a manual thermometer.
One point to emphasize in particular is that the temperature of the pages must not be ignored. When writing, the written temperature will also affect the quality of the binding. Some factories put good pages on the outside, and they start to glue when they arrive at the workshop. Because of the temperature difference between the indoor and outdoor (especially in the winter), the temperature of the pages is low, which will directly affect the quality of the glue. Therefore, within a few hours before rubber binding, it is necessary to transport the pages of the book to the workshop first, to minimize the temperature difference, and to minimize the quality problems caused by the temperature of the pages. The adhesive thickness is generally controlled at about 1mm.
Of course, there are still many factors that affect the quality of glue-binding. Everyone's experience is also very rich. I hope that the printing colleagues can write it out and we will communicate together.
Binding quality experience
December 19 09:07:23, 2023
Flourescent Drawing Board Guangdong Jishengke Industrial Co.,Ltd , https://www.jskpad.com