The hot melt adhesive used by the hot melt glue machine is a substance that firmly bonds various materials together by interface action (chemical force, physical force), referred to as glue for short. Humans have a long history of using adhesives. Early humans were inspired by the phenomenon of bonding in nature and began to use natural adhesives, such as blood glue, bone glue, rosin, natural asphalt, starch, lime, etc. According to records and textual research, as far back as 5,300 years ago, humans used mixed water and clay to glue stones and other tools into life. During the Qin Dynasty, people used mortar made of glutinous rice syrup and lime as an adhesive for the foundation stone of the Great Wall. Both China and Japan used bone glue to bond armor, scabbards, and bows in ancient times. The hot-melt glue machine unearthed the golden face bronze figure head from the sacrificial pit of Sanxingdui, Guanghan, Sichuan in 1986. It traces the time when the Chinese people applied the adhesive back to the Xia and Shang periods 4000 years ago. The gold face mask is expanded from gold foil. It is glued on the bronze head with a maroon Chinese lacquer and lime.
Although adhesives have been used for a long time and have achieved some results, they have remained at the level of using natural rubber for a long time, and the performance limitations of natural adhesives (low bonding strength, poor durability, etc.) limit Application and development of bonding technology.
In the 1930s, due to the development of modern large-scale industry and synthetic polymer materials, synthetic adhesives appeared. Synthetic adhesives for hot melt glue machines have more varieties and stronger adhesion than natural adhesives. And better durability and other characteristics. With the emergence of synthetic adhesives, adhesives have been widely used, and the importance of adhesives in industry and daily life has become more and more significant. Today, synthetic adhesives account for more than 90% of the total output of adhesives in the world and play a pivotal role. It is also a special hot melt adhesive for hot melt glue machines.