Analysis of the causes of bubbles after PUR hot melt adhesive bonding – Gonottech
PUR adhesive is a wet-reactive polyurethane hot melt adhesive, which is heated to melt liquid glue in a heated and sealed glue melting equipment, which can coat, dispense and spray the surface of the object that needs to be bonded. After gluing, the bonding should be completed within the opening time to ensure that the effect after bonding is the best, but in the bonding process, there will be bubbles, what is the reason? The following Gunuotai technicians will introduce it to you.
1. Whether the temperature of the glue tank is too high, if the temperature is too high and the heat resistance of the hot melt adhesive is not good, this phenomenon may occur;
2. The problem of hot melt adhesive itself, hot melt adhesive is not completely melted and mixed during the production process, and the air in the rubber will be released during the user’s heating process, or the hot melt adhesive is not vacuumed or pumped incompletely during the production process.
3. There are bubbles in the nozzle, you can think about whether the temperature of the hot melt adhesive machine is too high, and whether there is residual glue that has not been drained. You can try to drain the glue for a few minutes to see if the colloid is smooth and bubble-free.
4. There are no bubbles in the nozzle, there are bubbles after the reaction, one may be that there is tension after bonding, external force is pressurized, the strength is not enough, or it is not pressed well. Another possibility is that after pasting, it is not positioned and pressurized in time, so that it bounces off when it first sticks, leading to the edges, or bubbles at both ends.
The above is the analysis of why there are bubbles after PUR hot melt adhesive bonding introduced by Gunotech mobile phone TP and middle frame bonding manufacturers, hoping to provide you with reference.
Modified PU mobile phone TP and middle frame bonding hot melt adhesive (GNT-8868H) is a kind of high bonding strength cross-linked structural adhesive, which has good fluidity when heated and is convenient for coating. It has the characteristics of rapid melting by heating and rapid cooling (about 10 seconds) to achieve high-strength adhesion. It can meet the bonding requirements of structural components of mobile electronic products.
1. One-component, 100% cured matter, no solvent, no pollution, no toxicity. Water-resistant, oil-resistant, acid-resistant.
2. Fast curing, easy to wet, large adhesion and high strength. Stable performance, excellent toughness and filling after curing.
3. It is widely used and can bond a variety of materials, including some difficult-to-stick plastics.
4. Fast bonding speed, high production efficiency, very suitable for automatic assembly operations.
5. For narrow structural parts, reliable bonding can be achieved.
6. Rework does not damage the decorative parts and frame.
Shenzhen Gunotai Technology Co., Ltd. focuses on bonding technology related to mobile terminal electronic products. Perfect TP and middle frame separation technology (mobile phone repair and screen removal), low breakage rate (0.2%). Mobile phone TP and middle frame bonding automatic production line, quality and quantity. Service Hotline: Mr. Zhang Official Website Address: http://www.szgntgx.com/
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