新闻中心
First, give the answer:The pressing time for wireless adhesive packaging of books and periodicals is usually between 1.0-2.5 seconds. The thicker the paper, the higher the weight, and the lower the ambient temperature, the longer the pressing time needs to be.But ‘best’ has no standard value, only matching values. The experience of adjusting the machine in the spring of 2026 at a tutoring and printing factory in Jiangxi has made this matter very clear.
This factory owner works as a high school teaching assistant, running 70g of adhesive paper for the content and 250g of copperplate paper for the cover all year round. The equipment and rubber particles have not been replaced, but after the Spring Festival, the waste rate suddenly increased from 0.8% to 3.1%, and the problem is concentrated in “local empty glue on the spine and page flipping”. The first reaction of the workshop was that there was a problem with the rubber particles. Half a ton of goods were returned, and the problem persisted even after changing to a new batch.
After checking each item, the technicians found that the only change was the workshop environment temperature – before the Spring Festival, the warm air in the workshop was turned on at about 18 ℃, but after the holiday, the warm air was turned off to save electricity, and the actual measurement was only 9 ℃. Low temperature causes the adhesive to lose its fluidity before the compression is completed, resulting in insufficient penetration depth and the formation of an empty adhesive that appears to have adhesive on the surface but has not actually penetrated into the fibers.
| round | adjusted content | Waste rate |
|---|---|---|
| Initial | Press for 1.2 seconds/melt adhesive at 172 ℃ | 3.1% |
| Round One | The melt adhesive is raised to 182 ℃, and the pressure remains unchanged | 2.4% (slight burnt smell) |
| the second round | The melt adhesive returns to 175 ℃, and the compression is extended to 1.8 seconds | 1.1% |
| the third round | Pressing for 2.2 seconds+preheating with added book cores | 0.3% |
The key turning point is in the second round: although simply heating up can also improve fluidity, the cost is the accelerated thermal aging of the glue, the appearance of burnt taste and yellowing, which belongs to drinking poison to quench thirst. Extending the compression time is the right solution – it provides sufficient penetration window for the adhesive solution without increasing thermal damage.
Install an infrared preheating section behind the milling and before gluing to raise the temperature of the back of the book core to around 35 ℃, which is equivalent to reducing the temperature difference between the glue and the cold paper. After completing this step, the pressing time can be adjusted appropriately, and the production capacity loss can be compensated for. The final stability is achieved with a combination of 2.2 seconds of compression, 175 ℃ of melt adhesive, and 35 ℃ of book core preheating.
Guangzhou Sunlife Trading also conducts troubleshooting in this order when providing computer support to customers. The technical data sheet of Sunlife’s hot melt adhesive book series will provide recommended adhesive temperature and pressing time intervals, making it convenient for the workshop to directly compare, rather than relying on the technician’s hand feel for retesting.
Q: Is the longer the pressing time, the more firm it is?
Answer: No. Extending beyond the curing window of the adhesive will not yield any benefits and will only slow down production capacity. It may also reduce the strength due to excessive squeezing and thinning of the adhesive layer. Finding the point where ‘no further extension will improve’ is the optimal value.
Q: Is it necessary to heat up the workshop in winter?
Answer: It is not necessary to heat up the entire workshop, as the cost is high. It is more economical to add local insulation and preheating of the book core to stabilize the temperature in the adhesive area.
Q: Do I need to retry the parameters after changing the paper?
Answer: Yes. The weight, coating, and fiber orientation all affect penetration. It is recommended to solidify a set of parameters for each commonly used paper combination and record them.
“Intelligent Manufacturing Empowering Digital Transformation – Green Development Integration and Innovation Exhibition!” Exhibition Dates: April 11 – April 15 Venue: Guangdong Modern International Exhibition Center, Dongguan, China
Xiao Wu’s fast printing shop received a graduation commemorative book, 300 copies, and found that nearly 10% of the pages were scattered before submitting. The customer was pressing hard, so he dealt with it overnight. This is his summary of the scattered pages of first aid and root cause improvement stories. First aid: delivered on […]
In the production of pearl cotton packaging, the quality of EVA hot melt adhesive directly determines the adhesion strength, production efficiency, and long-term stability of the product. Choosing the wrong adhesive can easily lead to problems such as wire drawing blockage, debonding and edge opening, high temperature yellowing, and low temperature brittleness, which not only […]
