Due to their uniqueness, quick-setting hot melt adhesives have gained usage in many industries where a quick and strong bond is a requirement. The ease of use and the ability of such adhesive to set relatively fast – in seconds right up to minutes depending on the combinations of factors including type and temperature of adhesive and substrates – make hot melt adhesives a good choice among other types of adhesives.
Why Do hot melt adhesives Form Quickly With Heat?
In comparison to other adhesives, hot melt adhesives do not require chemical curing or drying, instead they set by cooling down. When they are heated, they become liquid, are readily able to spread and fill up gaps and will harden upon cooling. Cooling occurs rather quickly. As a result of which, manufacturers can cut down on their idle time when executing processes. In fact, the setting time of hot melt adhesive can vary from a few seconds to a few minutes. Nevertheless, for most industrial uses where speed is required, most formulations are designed to a few seconds.
Things That Affect Setting Time the Most
1. Type of Hot Melt Adhesive
Hot melt adhesives come in different types based on their use and setting time. For example low melting adhesives work on heat sensitive materials and dry quicker than standard hot melting adhesives. Hot melt adhesives of the thermoplastic type, which are extensively used in packaging, wood working and electronics, generally always dry quickly making them highly effective for fast-paced production processes.
2. Temperature of Work Area
The setting time of a hot melt adhesive is also affected by the usage temperature. For instance, high application temperature can enhance the liquid phase. However, the limitation of such application is that thermoplastics are most usable at high temperatures, therefore when applied at such high temperatures, they dry and set quickly to avoid massive wait time within assembling lines.
3. Material being treated
Different types of substrates can in addition, assist in settling at the correct time. For instance, metals that are good thermal conductors can bring about high rates of heat loss, thus increasing the rate of cooling and setting as well. However, insulating type substrates plasics and fabrics would mean that heat are retained and that can cause a larger gap for when the adhesive is open to use before setting.
Industrial Applications Requiring Fast Setting Times
Packaging, woodworking, automotive, and electronics are some of the industries which make extensive use of hot melt adhesives for their fast setting characteristics. For example, in the case of packaging, hot melts make it possible to carry out high speed automatic carton sealing without any lengthy waiting period for the seal to set. It is the same case in electronics, a field where accuracy and reliability are absolutely critical, where the usage of fast curing adhesives speeds up assembly and increases product stability.
Hot melt adhesive technology provides an efficient solution to industries where strong and reliable bonds are required in a short period of time. With some setting types taking as little as several seconds or couple of minutes at most, depending on usage, these adhesives improve the effectiveness and productivity of several types of manufacturing processes. Given the improvements in adhesive technologies, the industrial users will see an opportunity to achieve even quicker setting times, thereby making hot melts suitable for fast assembly lines and other demanding scenarios.
