Hot-melt adhesive film products are a type of hot-melt sticky product, which are made of hot-melt adhesives into films. Its basic characteristics are the same as those of hot melt adhesive.
When we understand the parameters of hot melt adhesive film products, we often talk about a concept of melting point, which roughly indicates the temperature at which the hot melt adhesive film of this type will melt.
However, for products such as hot melt adhesive films, the melting point temperature we see is usually not a temperature, but a range, such as 70℃~85℃. Because only crystalline substances have an exact melting point temperature, for amorphous substances, there is no exact melting point temperature, and the hot melt adhesive film is actually a mixture, so its melting is also a process; there is no exact temperature point.
So, to be precise, the melting point of the hot melt adhesive film cannot actually be called the melting point but should be called the melting range. Taking the above 70°C~85°C as an example, it means that the hot melt adhesive film starts to melt at 70°C and does not melt until 85°C. Therefore, from a process point of view, when we use this hot-melt adhesive film, the operating temperature needs to be at least 85°C or more to melt the hot-melt adhesive film. In fact, the actual temperature is often higher than 85°C. 20 ℃ or so, the effect will be better.
The melting range of hot-melt adhesive film is generally measured by a special melting point measuring microscope. We first take a small piece of hot-melt adhesive film with a blade and place it on the microscope slide, then place the slice under the microscope and slowly heat up and heat the slice. Then observe the melting situation of the hot-melt adhesive film through a microscope and thus record the melting range of the hot-melt adhesive film. Therefore, the melting range of the hot melt adhesive film is an observation value in many cases, not a very accurate value, but it also has a certain significance for guiding the process.
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