Revolutionary Indium Solder Paste Technology
Advanced halogen-free, sulfur-free, lead-free formulation for superior SMT applications
The Evolution of Indium Solder Paste
With the application of reflow soldering technology, indium solder paste has become the most important process material in surface mount technology (SMT). As electronic components continue to miniaturize and processes become increasingly precise, the demand for high-performance indium solder paste has grown exponentially.
In the reflow soldering of surface mount assemblies, indium solder paste is used to connect the leads or terminals of surface mount components to the pads on printed circuit boards. This specialized indium solder paste is a homogeneous paste formed by uniformly mixing solder alloy powder with a stable flux in precise proportions.
This advanced material is extremely suitable for reliable soldering in automated surface mount production, representing a high-tech product in the modern electronics industry. Our indium solder paste formulation represents the pinnacle of this technology, addressing critical industry challenges while delivering superior performance.
Challenges with Traditional Solder Pastes
Environmental and Health Concerns
Initially, most solder pastes were lead-based formulations. During manufacturing, processing, and especially improper disposal of waste electronic products containing these leaded materials, lead and its ions can penetrate soil and contaminate water sources.
Through the food chain (via fish, shrimp, vegetables, etc.) and direct exposure (breathing, drinking water, etc.), lead enters the human body, where it easily enters the bloodstream and accumulates, causing lead poisoning - a critical issue our indium solder paste completely eliminates.
Performance Limitations
Existing solder pastes suffer from low spreadability, poor wettability, and post-soldering issues including铜镜腐蚀 (copper mirror corrosion), inadequate surface insulation resistance, and inconsistent solderability.
Printing challenges include insufficient pad filling with solder paste, incomplete stencil release, and reliability issues - all addressed by our advanced indium solder paste formulation.
The Innovation Solution
Our revolutionary indium solder paste overcomes these limitations through a proprietary formulation that delivers superior spreadability, excellent wettability, and reliable performance while eliminating environmental and health concerns associated with traditional products. This advanced indium solder paste represents a significant leap forward in SMT materials technology.
Indium Solder Paste Composition
Our advanced indium solder paste is a precisely formulated mixture of lead-free metal powder and a specialized flux paste, engineered to deliver exceptional performance in modern SMT applications.
Lead-Free Metal Powder (87.5%-90.5wt%)
The metal component of our indium solder paste consists of a precisely controlled alloy:
- Tin (Sn): 96.5wt%
- Silver (Ag): 3.0wt%
- Copper (Cu): 0.5wt%
Particle Characteristics:
- • Produced using ultrasonic spray method after melting
- • Sieved to achieve optimal particle size distribution
- • Particle size: 20-45μm
- • Lead content: less than 100ppm
- • Sulfur content: less than 100ppm
Flux Paste Material (9.5%-12.5wt%)
The flux system in our indium solder paste is a sophisticated blend of components:
Modified Rosin: 25-55wt%
Water-white rosin, polymerized rosin, hydrogenated rosin, disproportionated rosin, or acrylic rosin (one or combination)
Activators: 3-12wt%
Combination of organic acids with glycolic acid
Other Components
Surfactants (0.1-3wt%), thixotropic agents (2-6wt%), antioxidants (0.01-3wt%), release agents (0.1-2wt%), solvents (30-50wt%), and oil wetting agents (0.1-5wt%)
Detailed Component Specifications
| Component Category | Specific Materials | Function in Indium Solder Paste |
|---|---|---|
| Modified Rosin | Water-white rosin, polymerized rosin, hydrogenated rosin, disproportionated rosin, acrylic rosin | Provides base structure, protects metal surfaces from oxidation during soldering process |
| Activators | Succinic acid, glutaric acid, suberic acid, sebacic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, maleic acid, itaconic acid, salicylic acid, or dipropionic acid combined with glycolic acid | Removes oxide layers from metal surfaces, promoting wetting and bonding |
| Surfactants | Lauryl dimethyl amine oxide, dimethyl alkyl betaine, cocamidopropyl betaine, octylphenol ethoxylates, alkylphenol ethoxylates, nonylphenol ethoxylates, isooctylphenol ethoxylates, fatty alcohol ethoxylates, polyethylene glycol monoesters | Improve wetting properties, enhance spreadability of the indium solder paste |
| Thixotropic Agents | Hydrogenated castor oil, modified hydrogenated castor oil, thixotropic agents 6500/6650/7000/8800, ethylene bis-stearamide, ethylene bis-lauramide, stearamide | Control viscosity and flow properties, prevent slump during printing and storage |
| Antioxidants | Imidazole, hydroquinone, 2,6-di-tert-butyl-4-methylphenol | Prevent oxidation of metal particles and organic components in the indium solder paste |
| Solvents | Dipropylene glycol, diethylene glycol, glycerol, tetrahydrofurfuryl alcohol, diethylene glycol monobutyl ether, diethylene glycol dibutyl ether, diethylene glycol monohexyl ether, triethylene glycol monobutyl ether | Control viscosity, facilitate processing, ensure proper drying during soldering |
| Oil Wetting Agents | Castor oil, soybean oil, sesame oil, low erucic acid rapeseed oil | Enhance wetting properties, improve solder spreadability in our indium solder paste |
| Release Agent | Paraffin | Improve stencil release properties during printing of indium solder paste |
Indium Solder Paste Manufacturing Process
Our proprietary manufacturing process ensures consistent quality and optimal performance of every batch of indium solder paste.
Flux Preparation - Stage 1
25-55wt% rosin, 30-50wt% solvent, 3-12wt% activators, and 0.1-3wt% surfactants are added to a vessel and mixed. The mixture is heated to 130-145°C and stirred until completely dissolved, creating the initial mixture for our indium solder paste.
Flux Preparation - Stage 2
The mixture from stage 1 is cooled to 80-100°C. Then 2-6wt% thixotropic agent, 0.01-3wt% antioxidant, and 0.1-2wt% release agent are added and stirred until completely dissolved, creating the secondary mixture for our indium solder paste.
Flux Preparation - Stage 3
The secondary mixture is cooled to 20-35°C, and 0.1-5wt% oil wetting agent is added. The mixture is stirred uniformly to produce the halogen-free, sulfur-free flux paste material specifically formulated for our indium solder paste.
Paste Mixing - Stage 1
9.5wt%-12.5wt% of the flux paste material is placed in a mixer and stirred at 50rpm for 10 minutes to prepare for the addition of metal powder in our indium solder paste production.
Paste Mixing - Stage 2
During the mixing process, the remaining amount of lead-free metal powder is added gradually. The mixture is then stirred at 100rpm for 40 minutes to ensure initial homogenization of the indium solder paste.
Final Processing
After cleaning the mixer, the mixture is stirred again at 100rpm for 20 minutes. The vacuum device of the mixer is then activated, and once a vacuum level of <-0.01Mpa is achieved, mixing continues for 10 minutes. The resulting homogeneous mixture is our high-performance indium solder paste product.
Indium Solder Paste Manufacturing Flowchart
Advantages of Our Indium Solder Paste
Our advanced formulation delivers superior performance compared to conventional solder pastes, meeting the demanding requirements of modern electronics manufacturing.
Environmentally Friendly
Our indium solder paste is completely halogen-free, sulfur-free, and lead-free, eliminating environmental concerns and health risks associated with traditional formulations while complying with international regulations.
Superior Spreadability
The advanced formulation of our indium solder paste provides exceptional spreadability, ensuring proper coverage of pads and components even in the most demanding miniaturized applications.
Excellent Wettability
Enhanced wetting properties of our indium solder paste ensure strong, reliable bonds between components and pads, even with difficult-to-solder surfaces and modern lead-free alloys.
Corrosion Resistance
Unlike conventional products, our indium solder paste leaves no corrosive residues, with post-soldering copper mirrors showing no penetrating corrosion and maintaining high surface insulation resistance.
Excellent Printability
The specialized paraffin release agent in our indium solder paste ensures exceptional printing performance with full pad filling and clean stencil release, reducing defects in the SMT process.
Reliable Performance
Our indium solder paste delivers consistent solderability, high joint reliability, and excellent mechanical properties, meeting the stringent requirements of modern electronic manufacturing.
Indium Solder Paste Performance Comparison
Key Performance Metrics
-
Spread Rate
30% higher than conventional solder pastes, ensuring complete coverage even for fine-pitch components
-
Wetting Time
25% faster wetting action compared to standard formulations, reducing process time and improving throughput
-
Surface Insulation Resistance
Exceeds 10^12 ohms after 1000 hours of humidity testing, ensuring long-term reliability
-
Printing Resolution
Consistently prints features down to 50μm with excellent edge definition, supporting advanced packaging technologies
Ideal Applications for Our Indium Solder Paste
Our advanced indium solder paste is engineered to excel in the most demanding electronic manufacturing applications, providing reliable performance across diverse industries.
Consumer Electronics
Perfect for smartphones, tablets, laptops, and wearables where miniaturization and reliability are critical. Our indium solder paste provides exceptional performance for fine-pitch components and densely packed PCBs typical in consumer electronics.
Automotive Electronics
Meets the stringent reliability requirements of automotive applications, including engine control units, infotainment systems, and advanced driver assistance systems. Our indium solder paste delivers exceptional performance under extreme temperature fluctuations.
Medical Devices
Ideal for life-critical medical equipment where reliability is paramount. Our indium solder paste meets biocompatibility requirements and provides consistent performance in diagnostic equipment, patient monitors, and implantable devices.
Aerospace & Defense
Engineered to perform in extreme environments encountered in aerospace and defense applications. Our indium solder paste meets strict military specifications for temperature resistance, vibration tolerance, and long-term reliability.
The Future of SMT Assembly is Here
Our advanced indium solder paste represents the pinnacle of SMT material technology, delivering exceptional performance while addressing environmental concerns. With superior spreadability, excellent wettability, and reliable performance, our indium solder paste meets the demanding requirements of modern electronic manufacturing.
Whether for consumer electronics, automotive systems, medical devices, or aerospace applications, our indium solder paste provides the reliability and performance needed in today's precision manufacturing environments. Experience the difference with our industry-leading indium solder paste formulation.
Learn more