Hot melt adhesive films have various performance requirements, and water resistance is one of them and one of the more frequently mentioned. Especially for the apparel industry, the water resistance of hot melt films is very important, as it is related to the durability of the garments made with hot melt films for non-turned seam bonding.
In layman's terms, water resistance is the ability of a material (usually fabric) to maintain a high bond strength after being soaked in water at a certain temperature and repeatedly rubbed after being bonded with a hot melt adhesive film.
The hot melt adhesive film with good resistance to water washing is TPU hot melt adhesive film and PO hot melt adhesive film. Because it is often used in clothing, there are usually certain requirements for the softness of the hot melt adhesive film, so TPU hot melt adhesive film is more commonly used. In addition, EVA hot melt adhesive film has a wide range of applications and has some resistance to washing, but not as good as TPU hot melt adhesive film.
There are different levels of wash resistance, such as room temperature wash, 60℃ wash, 90℃ wash, etc. The higher the temperature, the better the effect on the hot melt adhesive. The higher the temperature, the higher the requirement for the washing resistance of the hot melt adhesive film. In the case of TPU hot melt adhesive film, room temperature wash resistance is not a problem for most TPU hot melt adhesive films. However, not all TPU hot melt films can withstand 60°C washing.
Because there is a melting point problem for hot melt films, the initial melting point of many hot melt films may be lower than 60℃, and TPU hot melt films are no exception. Therefore, when the water temperature reaches 60℃, the adhesive film of the bonding material has produced a certain degree of melting, so of course, it cannot resist washing.
Therefore, the test requirement of 90℃ water washing resistance is even more demanding, and most of the TPU hot melt adhesive films may not meet this requirement. Only a very small number of TPU hot melt adhesive films and a few PO hot melt adhesive films can meet the 90℃ wash resistance condition, requiring a special high-temperature resistance formula.
So if you ask which is the best hot melt adhesive film for washing resistance, we often recommend TPU hot melt adhesive film, but if you don't have requirements for softness, you can also try PO hot melt adhesive film.
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