In the electronics industry, ultra - fine dicyandiamide plays an extremely crucial role. In printed circuit board (PCB) manufacturing, it is used in solder masks to enhance insulation, improve adhesion and patterning accuracy. When applied to conformal coatings, it provides protection against moisture, dust, and foreign objects. In semiconductor packaging, as a curing agent for epoxy molding compounds (EMC) and underfill adhesives, it improves packaging strength, optimizes thermal performance, and enhances connection reliability. In the coating of electronic components, whether for capacitors or resistors, it can enhance insulation, stabilize performance, and improve heat dissipation. Thanks to these applications, ultra - fine dicyandiamide significantly improves the reliability, stability, and performance of electronic devices, driving the continuous progress of the electronics industry.

I. Printed Circuit Board (PCB) Manufacturing

(I) Solder Mask

1. Enhanced Insulation Performance: On a PCB, reliable insulation between different circuit layers is required to prevent short - circuits. Ultra - fine dicyandiamide, as a curing agent in solder mask inks, undergoes a cross - linking reaction with resins to form a highly dense three - dimensional network structure. This structure can effectively block the abnormal conduction of current between different circuits. Even in high - voltage and high - frequency working environments, it ensures that each circuit operates independently. For example, in the PCB of a server motherboard, where a large number of high - speed signal lines are densely distributed, the use of a solder mask containing ultra - fine dicyandiamide can guarantee the stability and accuracy of data transmission, avoiding data errors or system failures caused by current leakage between circuits.

2. Improved Adhesion and Chemical Resistance: During PCB manufacturing, multiple chemical processing steps are involved, such as etching and cleaning. Subsequently, it may also come into contact with chemical substances like soldering fluxes and cleaning agents. The solder mask cured with the participation of ultra - fine dicyandiamide has excellent adhesion to the PCB substrate and is not prone to peeling off during chemical processing. At the same time, its high chemical stability after curing enables it to resist the erosion of various chemical substances, ensuring that the solder mask maintains good performance throughout the entire life cycle of the PCB. Take the PCB in automotive electronics as an example. In harsh environments such as the engine compartment, it has to withstand high temperatures, high humidity, and various corrosive gases. The solder mask containing ultra - fine dicyandiamide can effectively protect the circuits and extend the service life of the PCB.

3. Precise Patterning: With the development of electronic products towards miniaturization and high - performance, the circuit design of PCBs has become increasingly sophisticated, and extremely high requirements are placed on the patterning accuracy of solder masks. The small particle size of ultra - fine dicyandiamide gives it good dispersibility in the ink system, enabling high - precision lithographic imaging. Through the lithography process, solder mask patterns with clear edges and precise dimensions can be formed on the PCB, ensuring that the insulation distance between circuits meets the design requirements and meeting the manufacturing needs of high - density interconnect (HDI) PCBs, such as those in lightweight and portable devices like smartphones and tablets.

(II) Conformal Coating

1. Protection Against Moisture and Salt Spray Erosion: In some electronic devices used in humid environments or coastal areas, such as ocean monitoring instruments and outdoor communication base stations, the PCB faces severe challenges from water vapor and salt spray. The conformal coating containing ultra - fine dicyandiamide can form a uniform and continuous protective film on the PCB surface. Its cured structure is tight, making it difficult for water molecules and salt to penetrate, thus effectively preventing the oxidation and corrosion of the metal circuits on the PCB. Experiments show that after the PCB treated with this conformal coating is exposed to a salt spray test chamber for thousands of hours, the circuits remain intact, greatly improving the reliability of electronic devices in harsh environments.

2. Dust and Foreign Object Protection: During the production, transportation, and use of electronic devices, they inevitably come into contact with dust, fibers, and other foreign objects. Once these foreign objects land on the PCB, they may cause circuit short - circuits or affect the heat dissipation of electronic components. The ultra - fine dicyandiamide in the conformal coating can make the coating surface smooth, reducing the adhesion of dust and other foreign objects. At the same time, the flexibility of the coating ensures that it remains intact when the PCB is subjected to vibration or impact, continuously providing protection for the PCB and ensuring the stable operation of electronic devices, such as in industrial control equipment and aerospace electronic systems, which have extremely high requirements for reliability.

II. Semiconductor Packaging

(I) Epoxy Molding Compound (EMC)

1. Increased Packaging Strength and Reliability: During the packaging of semiconductor chips, EMC is required to isolate the chip from the external environment and provide mechanical support. Ultra - fine dicyandiamide, as a key curing agent in EMC, can react rapidly with epoxy resins to form a high - strength cured product. This not only enhances the overall mechanical strength of the package but also effectively resists external force impacts during transportation, installation, and use, preventing problems such as cracking and delamination between the chip and the packaging material. For example, in the semiconductor chip packaging of an automotive engine control unit (ECU), which has to withstand the intense vibration and high - temperature environment generated by the engine operation, the EMC containing ultra - fine dicyandiamide can ensure that the chip operates stably in harsh conditions for a long time.

2. Optimized Thermal Performance: Chips generate a large amount of heat during operation, and good thermal management is crucial for chip performance and lifespan. The EMC cured with the participation of ultra - fine dicyandiamide has a relatively low coefficient of thermal expansion, which can better match the coefficients of thermal expansion of the chip and the substrate. This helps to reduce chip damage caused by thermal stress during temperature changes. At the same time, the thermal conductivity of EMC can also be improved by adding specific fillers and optimizing the formula, thereby enhancing the heat dissipation efficiency of the chip and ensuring the temperature stability of the chip during high - performance operation, such as in high - performance computing chips and 5G communication chips, which have extremely high requirements for heat dissipation.

3. Improved Packaging Processability: During the molding process of semiconductor packaging, EMC needs to have good fluidity and filling ability to ensure that it can completely enclose the chip and fill tiny gaps. The small particle size of ultra - fine dicyandiamide allows it to be evenly distributed in the EMC system without affecting the fluidity of the system. At the same time, its curing reaction is highly controllable, and the curing conditions (such as temperature and time) can be adjusted to meet different packaging process requirements, improving packaging production efficiency and the yield rate, and meeting the needs of large - scale semiconductor production.

(II) Underfill Adhesive

1. Enhanced Chip - to - Substrate Connection Reliability: In flip - chip packaging technology, underfill adhesives are used to fill the gaps between the chip and the substrate to enhance the connection strength between the chip and the substrate. Ultra - fine dicyandiamide, as the curing agent of the underfill adhesive, can make the adhesive form a tough and flexible colloid after curing. This can effectively disperse the stress caused by the difference in the coefficients of thermal expansion between the chip and the substrate, preventing fatigue cracking of solder joints during the thermal cycling process and improving the reliability of the chip - to - substrate connection. For example, in the flash memory chip packaging of a solid - state drive (SSD), frequent read - write operations cause the chip to heat up. The ultra - fine dicyandiamide in the underfill adhesive can ensure that the connection between the chip and the substrate remains stable under long - term thermal cycling, guaranteeing the safety of data storage and transmission.

2. Improved Signal Transmission Integrity: With the continuous increase in the requirements for high - speed signal transmission in electronic devices, the electrical properties of underfill adhesives have also become crucial. The underfill adhesive containing ultra - fine dicyandiamide has the characteristics of a low dielectric constant and low dielectric loss after curing, which helps to reduce signal attenuation and distortion during transmission, ensuring that high - speed signals can be accurately and quickly transmitted between the chip and the substrate. In the chip packaging of high - speed communication devices such as switches and routers, this performance plays a key role in ensuring the high - speed and stable transmission of data.

III. Electronic Component Coatings

(I) Capacitors

1. Enhanced Insulation Performance and Stability: Capacitors are commonly used energy - storage components in electronic devices, and their insulation performance directly affects the reliability of the device. Coating the dielectric material surface of capacitors with a coating containing ultra - fine dicyandiamide can further improve their insulation performance. After ultra - fine dicyandiamide cures with the resin in the coating, the formed insulation layer can effectively block leakage current and reduce capacitor losses. At the same time, this coating can also enhance the chemical stability of the dielectric material, preventing its performance degradation due to environmental factors during long - term use, ensuring that capacitors can stably store and release charge under different working conditions. For example, in the capacitors of power supply filtering circuits, good insulation performance can ensure the stability of power output.

2. Increased Voltage Resistance: In some high - voltage application scenarios, such as power electronics equipment and pulse generators, capacitors need to withstand high voltages. The coating containing ultra - fine dicyandiamide can improve the voltage resistance of capacitors. By forming a uniform and dense insulation protective layer on the dielectric surface, it can effectively suppress corona discharge and partial discharge phenomena, preventing the capacitor from being broken down under high voltage and increasing the working voltage range and reliability of the capacitor.

(II) Resistors

1. Protecting the Resistor Body and Stabilizing the Resistance Value: The stability of the resistance value of resistors is crucial for the performance of electronic circuits. Ultra - fine dicyandiamide, when used in the coating material of resistors, can form a solid protective film on the surface of the resistor body. This film can prevent the resistor body from being affected by external environmental factors such as moisture, chemical gases, and mechanical wear, avoiding the oxidation and corrosion of the resistor body, and thus ensuring that the resistance value of the resistor remains stable during long - term use. For example, in precision measuring instruments, a slight change in the resistance value of a resistor can lead to a large error in the measurement result. The coating containing ultra - fine dicyandiamide can effectively ensure the accuracy and reliability of the resistor.

2. Improved Heat Dissipation Performance: Resistors generate heat during operation, and good heat dissipation performance helps to reduce the operating temperature of resistors, improving their stability and lifespan. The ultra - fine dicyandiamide in the coating can, through synergistic effects with other functional fillers, optimize the thermal conductivity of the coating. This enables the heat generated by the resistor to be more effectively dissipated into the surrounding environment, avoiding resistance value drift caused by excessive temperature and ensuring that the resistor can still operate normally under high - power working conditions. For example, in the resistors of power amplifiers, good heat dissipation performance is required to ensure the stability of the circuit.