In the manufacture and repair of electronic equipment, the bonding of circuit boards is an important step that cannot be ignored.Choosing the right pcb glue not only ensures the stability and longevity of the circuit board,but also affects the overall performance of the equipment.The six types of adhesives commonly used on the best glue for circuit board, namely,electrical protective adhesives,red glue,yellow adhesives,thermal conductive silica gel, silicone adhesives,and hot melt adhesives,have a wide variety of technical requirements,and their applications vary widely,providing many process conveniences for the modern electronic manufacturing industry.The following is a summary of the characteristics and applications of related adhesives.
1.Electrical sealant
Electric anti best glue for circuit board is a kind of adhesive used for covering circuit boards,which is mostly in the liquid state and some have a relatively high viscosity in the semi liquid state. As the largest glue used on modern electronic circuit boards and with the largest user base,it can provide excellent protection for circuit boards in many harsh environments, such as moisture, mold, salt spray, etc., greatly improving their service life. It is relatively convenient to immerse,brush,or machine spray.And the faster curing speed will not affect production.
2.Red gum
Red glue is a polyolefin compound that can easily solidify when heated. When the temperature it is exposed to reaches the freezing point of 150 ℃, red glue begins to change from a paste to a solid. Using this property, you can fix the mounting components by dispensing or printing. The mounting red glue used for components can be heated and solidified through an oven or reflow soldering. Components on circuit boards, especially double-sided mounting circuit boards, are fixed using patch red adhesive during wave soldering to prevent small patch components on the back from falling into the furnace tin.
3.Xanthan gum
The yellow pcb glue is a kind of hydraulic adhesive, which has a pungent smell and is a soft, self-adhesive gel like material. It has excellent insulation, moisture-proof, shockproof and thermal conductivity, enabling electronic components to operate safely under harsh conditions. It is prone to solidification, and the curing speed is dependent on ambient temperature, humidity, and wind speed: the higher the temperature, the lower the humidity, and the greater the wind speed, the faster the curing speed, and vice versa. Placing coated components in the air can cause slow peeling. Note that the operation should be completed before surface peeling.
4.Thermal conductive silicone
Thermal conductive silicone, also known as thermal conductive paste or heat dissipating paste, is a high thermal conductive insulating silicone material that, unlike thermal conductive silicone grease, almost never solidifies and can maintain the paste state when used for a long time at temperatures ranging from - 50 ℃ to+250 ℃. It has excellent electrical insulation and thermal conductivity, as well as low oil separation (tends to zero), high and low temperature resistance, water resistance, ozone resistance, and weather aging resistance. Its characteristics are non-toxic, odorless, and non corrosive, meeting ROHS standards and relevant environmental requirements, and having stable chemical and physical properties.
5.Silicone adhesive
Silicone adhesive is a type of ointment that, once exposed to moisture in the air, solidifies into a tough, rubbery solid material. Silicone adhesive is commonly known as glass adhesive because it is often used for bonding and sealing glass. The adhesive should be stored in a sealed manner. The mixed rubber should be used up at one time to avoid waste.
6.Hot melt adhesive
The hot melt adhesive strip is a solid adhesive made of ethylene vinyl acetate polymer (EVA) as the main material,modified rosin resin or petroleum resin, and other components. It is a plastic, non-toxic,odorless,green,and environmentally friendly adhesive.Within a certain temperature range, the physical state of the hot melt adhesive changes with temperature, while the chemical properties remain unchanged. Completely free of water or solvents,it has the characteristics of rapid adhesion,high strength,aging resistance,non-toxic,good thermal stability, and adhesive film toughness.Heat the hot melt adhesive to the use temperature,use a spray gun or apply it to the adhesive.The adhesive and molding work must be completed within the opening time of the adhesive,and the adhesive must be clamped and cooled to normal temperature.The hot melt adhesive is solid at a suitable temperature,heated and melted into a liquid.
After being cooled at room temperature, it can be bonded within a few seconds, effectively fixing electronic components and wiring harnesses.Different adhesives have different applications. When using or searching for corresponding products, it is indeed necessary to consult relevant professionals to reduce errors and avoid affecting production and causing material losses on the best pcb glue for circuit board.