What is the use of hot melt adhesive in car filters?

Nowadays, with the development of the automotive market, car filters are becoming increasingly diverse. There are various types of styles, such as drum, curved, and flat. Large vehicles such as general trucks commonly use drum filters, while small models such as family cars and SUVs use flat filters. At present, the automotive industry is paying more and more attention to lightweight, energy conservation, environmental protection, low odor, low emissions, low pollution, and noise reduction and shock absorption. Therefore, the adhesive required in this regard is more environmentally friendly and non-toxic. And hot melt adhesive is very suitable. It belongs to environmentally friendly chemical products with fast curing, low odor, and convenient and fast adhesion. This naturally became the development direction of adhesives used in the automotive filter industry.
The bonding of automotive filters mainly involves folding the filter element, fixing the mesh, bonding the end cover, bonding the filter joint, and fixing the frame. A few simple examples:

1. Filter origami adhesive
   The adhesion of filter origami requires hot melt adhesive to maintain stable viscosity at the set temperature value and uniform fluidity after full melting. Ensure that it does not produce bubbles. After applying the adhesive, the material needs to be placed in a drying oven to observe the changes in the adhesive paper without displacement or deformation;
2. Adhesive joint of filter joint
   This step refers to the bonding of the end connectors of the filter membrane and the joints on both sides of the filter membrane. Ordinary filters generally use EVA hot melt adhesive, PO hot melt adhesive, and PA hot melt adhesive. Air filters usually use EVA or PO hot melt adhesive, while oil filters now mostly use PA polyurethane hot melt adhesive for connection.
3. Air conditioning filter – border bonding
   Hot melt adhesive is also very suitable for bonding and sealing filter membranes and filter frames. The specifications of filters vary in each processing plant. Some filter manufacturers prefer to use a hot melt adhesive machine with a scraper to evenly scrape and apply hot melt adhesive inside the filter frame, and then manually stick the edge banding around the filter element. This type of operation is normal for processing plants with larger production volumes. Most of the adhesive used for sealing the edges of air conditioning filters is EVA hot melt adhesive, which requires good fluidity, high bonding strength, and excellent temperature resistance.