Filter Adhesive Standards
Filters primarily achieve functions such as filter layer shaping, frame connection, and housing sealing through the use of hot-melt adhesives. Hot-melt adhesives offer advantages such as low toxicity, minimal harm, solvent-free and low odor properties, as well as fast curing speed, making them widely used in filter products. Different adhesive application points and processes have distinct technical requirements for adhesives. Common points are as follows:
1. Frame Adhesive Function: Secure filter frame
Requirements:
Low odor
White or yellow color (matching filter paper)
Good thermal stability
Extended open time
Viscosity above 6000CPS/180℃, adhesive line remains smooth without dripping.
Common adhesive application methods: roller application, scraping, manual application. Considerations for frame adhesive selection: Different customers have varying process, cost, and performance standards, leading to the selection of adhesive types. Mainstream options include hot-melt adhesive pellets and hot-melt adhesive sticks.
2. Line Adhesive Function: Replace high-efficiency filter separators, providing separation and filter paper fixation.
Requirements:
Low odor
White or yellow color (matching filter paper)
Good thermal stability
No dripping at high temperatures, preventing uneven adhesive lines
Fast curing to meet rapid production needs
High hardness, especially for fiberglass paper
Good heat resistance, typically requiring no collapse of the filter core at 80°C
Common adhesive application method: spraying. Considerations for line adhesive selection: 1. Spraying method: single-sided or double-sided spraying on the filter paper, intermittent or continuous spraying. 2. The filter core's material, fold height, fold count, cold and heat resistance testing standards, all influence adhesive selection differences.
3. Other Adhesive Applications
Carbon Cloth Composite: Special filter material composed of non-woven fabric and activated carbon. Generally, pressure-sensitive hot-melt adhesive or polyolefin hot-melt adhesive is used, depending on customer processes.
Filter End Cap Sealing: Typically uses epoxy adhesive or organic silicone.
Fuel and Oil Filters: Mainly utilize high-temperature resistant polyamide hot-melt adhesive.
