Concentrol develops different solutions in adhesives. It is a division with a broad vision that produces products for very different sectors. It offers a wide range of adhesives of this type, from low viscosity ones for light supports, to high viscosity for more robust substrates.
Hot-melt netmelt adhesives are made of solid thermoplastic material at room temperature that by heat action melts to become a more or less fluid liquid, which can be applied on a wide variety of substrates to keep them together.
Application
Hot-melt adhesives are applied in several different ways. The application temperature of the adhesives depends on many factors, such as the heat sensitivity of the materials to be joined, the work cadence of the production line, the amount of adhesive, the environmental conditions of the packaging and the type of support. This may vary from 120 °C to 190 °C.
It is important to keep in mind that hot-melt adhesives must be applied with the exact amount required. Using too much adhesive can result in an unstable bond, while using an insufficient amount can make the bond very weak. Therefore, it is crucial to ensure the exact amount of adhesive to ensure a strong bond.
The equipment with which the adhesive is applied is fundamental. The melting equipment contains a heating element to melt the adhesive mixture into liquid state. Another relevant part of the equipment is the heated hose. This hose is responsible for conducting the heat from the heating element to the point of bonding. It is designed to withstand high temperatures, which guarantees a safe and reliable gluing.
The assembly can also be equipped with a variety of application devices, such as a gun, when applied manually, and an injector, a lip or a roller, when the process is automated. These devices are responsible for applying the liquid adhesive uniformly at the point of bonding.
The way in which the adhesive is applied depends on the application device and the customer needs. There are different types of application such as continuous cord, spiral or spray, lamination, application by points or by discontinuous cord.
To guarantee the correct application of the product, it is important that the equipment includes a controller to regulate the temperature, pressure and flow of adhesive, guaranteeing that the bond is carried out correctly.
Factors that affect the gluing
The choice of an adequate hot-melt adhesive for any gluing application is key to the success of a project. The factors that must be taken into account when working with hot-melt adhesives are the following:
- Ambient temperature is a relevant factor for operation. When the ambient temperature is too hot, the adhesives will not harden enough to create an adequate bond. On the contrary, if the temperature is too low, the adhesive will harden too fast and will not give time for the substrates to join before the adhesive hardens. In addition, the application temperature of a hot-melt adhesive must be high enough to allow the adhesive to extend uniformly.
- The type of support to be bonded is also a factor to consider. Some hot-melt adhesives are better for certain types of supports than for others. For example, some adhesives are more suitable for porous substrates, while others are better for smooth substrates. Selecting the correct adhesive for the substrate is important to ensure good adhesion.
- The working speed. Hot-melt adhesives harden quickly, so application time is limited. The speed at which the adhesive is applied must be quick enough to allow the adhesive to extend evenly before it hardens. If the speed is too slow, the adhesive will harden before it extends completely, which will result in bad gluing.
- Finally, the amount of adhesive applied is a key factor. An excess of adhesive can cause prolonged open time, which will harm production, in addition to a risk of substrate separation and unnecessary product consumption. On the other hand, if an insufficient amount of adhesive is applied, the gluing will not be effective due to the lack of contact surface.
The products of the NETMELT range are presented in different formats such as ground, diced or pillows, depending on the product. They can be stored between 5 and 35 ºC with a shelf life of up to 2 years, maintaining all their properties.
Concentrol shows its commitment to customer satisfaction researching and developing new products for its Netmelt line. This is achieved with the incorporation of advanced technologies and the use of quality raw materials to produce high performance products. The chemical company has a commitment to excellence and its customers, and seeks to offer them products of the highest quality to meet the needs of the industry.
