IPC Class III VoidingPerformance Solder Paste

TS107E is a widely used no‑clean, leaded solder paste that is specifically engineered to deliver the highest level of voiding performance in the industry. As an IPC Class III Voiding Performance Solder Paste, it meets the most stringent IPC 7095 Class III requirements for IPC Class III voiding, ensuring superior long‑term reliability in thermal cycling, high‑power, and mission‑critical applications. Beyond its exceptional voiding characteristics, TS107E also offers excellent ultra‑fine pitch printing, low head‑in‑pillow defects, and high in‑circuit probe test yield, making it the preferred choice for manufacturers who demand the highest quality and reliability standards.

Solder Paste Composition

TS107E IPC Class III Voiding Performance Solder Paste consists of Sn63/Pb37 alloy powder and solder flux. According to the technical datasheet, this product uses the Sn63/Pb37 eutectic alloy (63% tin, 37% lead) with a melting point of 183°C. The flux content is approximately 5% (by weight), utilising an ROL0‑grade activator system (the highest reliability level per IPC J‑STD‑004). This formulation is carefully optimised to minimise gas entrapment during reflow – a critical enabler for achieving IPC Class III voiding performance, as the flux chemistry promotes complete outgassing and coalescence, resulting in dense, void‑free solder joints.

Solder Paste Type – Customisable Powder Size Options

TS107E IPC Class III Voiding Performance Solder Paste is available in a wide range of powder sizes to suit different printing and dispensing needs, while maintaining its outstanding IPC Class III voiding performance across all variants. The product family offers the industry's broadest selection of Solder Paste Type options, including:

Regardless of the powder type chosen, TS107E consistently delivers industry‑leading IPC Class III voiding performance, ensuring that solder joints remain dense and reliable even in the most demanding thermal and mechanical environments.

Sn63/Pb37 Alloy Advantages

As a typical IPC Class III Voiding Performance Solder Paste, TS107E utilises the Sn63/Pb37 eutectic alloy, offering the following core benefits:

• Eutectic characteristics – melting point of 183°C, no plastic zone, rapid solidification during soldering, reducing cold solder risks and promoting dense joint formation;
• Mature technology – Sn63/Pb37 is the most widely applied alloy system, and its well‑characterised solidification behaviour contributes to IPC Class III voiding by enabling complete coalescence and minimal gas entrapment;
• Superior wettability – excellent performance across various PCB surface finishes, especially on CuOSP, promoting reliable joint formation and reducing voiding at the interface;
• Cost‑effectiveness – compared to lead‑free alloys, this product offers competitive material costs while delivering superior voiding performance.

This alloy system, combined with the optimised flux, ensures that TS107E produces dense, void‑free solder joints that consistently meet the IPC Class III voiding standard.

Flux and Electrical Reliability

The flux in TS107E employs an ROL0‑grade activator system (IPC J‑STD‑004 highest reliability level) and is halogen‑containing (confirmed by titration and silver halide tests). This flux system ensures that the IPC Class III Voiding Performance Solder Paste passes all of the following tests, while also providing the outgassing and coalescence characteristics essential for IPC Class III voiding:

These results confirm that the flux residue is electrically safe and reliable, while the flux chemistry itself is key to achieving IPC Class III voiding – the activator system ensures complete reduction of oxides and efficient outgassing during reflow, preventing voids from forming in the solder joint.

Printing Performance and Process Parameters

TS107E IPC Class III Voiding Performance Solder Paste demonstrates outstanding printing consistency and high process capability index (Cpk) on the printer, even at ultra‑fine pitch. The key printing parameters for this product are:

• Printing speed: 25–150mm/s (1–6 in/s), supporting high‑speed printing for fast cycle times and high throughput;
• Squeegee pressure: 0.18–0.27kg/cm (1.0–1.5lbs/inch); higher speeds require increased pressure;
• Squeegee angle: 60° (standard);
• Squeegee material: metal or polyurethane rubber (hardness 80–90 Shore);
• Stencil thickness: 100–150μm (4–6mil);
• Stencil separation speed: 3–10mm/s;
• Stencil material: recommended Alpha series electroformed/laser‑cut stencils.

This product exhibits minimal viscosity variation during continuous printing at 25°C/50%RH, significantly reducing cleaning frequency and improving production line efficiency. Consistent deposit geometry not only ensures reliable soldering but also contributes to IPC Class III voiding by providing uniform deposit volumes, which promote consistent outgassing and coalescence during reflow.

Handling and Process Guidelines

TS107E IPC Class III Voiding Performance Solder Paste must be stored refrigerated at 0–10°C (shelf life: 6 months). Prior to use, the paste should be allowed to warm to room temperature for approximately 4 hours (ensure temperature ≥19°C before opening), and then mixed:

• Manual mixing: can be stirred with a spatula until uniform;
• Centrifugal mixer (solder paste mixer): recommended speed below 300 RPM, with a pause after every 30–60 seconds of mixing;
• Important: Never mix solder paste recovered from the stencil with unused paste in the same container, as this will alter the rheological properties of the unused IPC Class III Voiding Performance Solder Paste.After printing, reflow should be completed as soon as possible. 

The reflow profile recommends a peak temperature of 210–220°C (above the 183°C melting point), and can be performed in air or nitrogen atmospheres. Following these guidelines helps preserve the product's IPC Class III voiding performance by ensuring optimal flux activity and coalescence.

Core Differentiating Advantages – Superior Voiding Performance and More

TS107E IPC Class III Voiding Performance Solder Paste offers three industry‑leading advantages:

• IPC Class III voiding performance – This product meets the highest IPC 7095 voiding classification – Class III. The IPC Class III voiding standard is the most demanding level, requiring exceptionally low void content in solder joints. TS107E consistently achieves this level, ensuring superior mechanical strength, thermal conductivity, and long‑term reliability in thermal cycling, power cycling, and high‑temperature storage applications. This is particularly critical for automotive, aerospace, and industrial electronics where failure is not an option.
• Low head‑in‑pillow defect rate – While the primary focus is on voiding performance, TS107E also provides outstanding resistance to head‑in‑pillow defects in BGA/CSP soldering, reducing open defects caused by PCB warpage and component coplanarity issues – ensuring that joints are not only void‑free but also electrically intact.
• Excellent probe testability – TS107E provides best‑in‑class in‑circuit probe test yield. After reflow, the solder joint surface has minimal, colourless, transparent flux residue, resulting in low probe contact resistance and significantly reducing ICT (in‑circuit test) misjudgements. 

This complements its IPC Class III voiding performance by ensuring that joints are both reliable and testable.

Application Scenarios and Supply Capacity

TS107E IPC Class III Voiding Performance Solder Paste has been deployed in volume production across the following sectors, where its IPC Class III voiding performance delivers tangible reliability improvements and compliance with the highest industry standards:

This IPC Class III Voiding Performance Solder Paste serves over 50 customers, with a monthly production capacity exceeding 3 tonnes and ample inventory, enabling delivery within 48 hours.