How to distinguish different types of hot melt adhesives by the shape of hot melt adhesives
1 block and granular hot melt adhesive
This kind of hot melt adhesive pellets has the largest output. Blocks are square, rounded, and granular are flat, diamond, and cylindrical. The colors are light yellow, white, red, black or translucent and colorless. When using, there must be a melting pot, after melting, scrape coating, roll coating, spray coating or extrusion coating.
2 stick hot melt adhesive
Usually it is a round rod-shaped rubber strip with a length of 150-300mm. The gluing tool is a hot melt gun rubber strip inserted into the barrel of the gun. After being heated, the trigger is pulled to push the rubber strip forward while extruding the melted glue. This kind of glue is yellow, white, red, or colorless and transparent, which is mainly used for bonding metal, electronic products, plastic parts and toys.
3Powdered hot melt adhesive
Most of them are used for fabrics and pads, and the glue "coating" must be realized through a dusting device. During bonding, the sizing lining material and other substrates are superimposed, and a tight bonding can be achieved by hot pressing. Such as fusible interlining for clothing, carpet backing, leather shoe padding. It is difficult to pulverize hot melt adhesives, and sticky blocks will appear due to frictional heating during mechanical pulverization, and chemical pulverization and cryogenic mechanical pulverization are required. The colors are mostly true colors.
4 film hot melt adhesive
The hot-melt adhesive is extruded into a film sheet into a roll product, which is cut into the required size when used, and is sandwiched between the substrates to achieve high bonding strength after hot pressing. The adhesive film can also be mixed with heat-curing ingredients, such as epoxy resin or cross-linking agent. The transparent adhesive film is used in the manufacture of automotive laminated safety glass and solar cell encapsulation. They include polyurethane film, polyvinyl butyral film, and EVA film. There is no need for transparent adhesive film to be used for bonding of plates on automobiles and airplanes.
