TENSAN TS‑501 is a Type 4 Solder Paste engineered specifically for mid‑temperature, lead‑free SMT processes. Formulated with a Sn‑Ag1‑Bi35 alloy, this solder paste type 4 product delivers exceptional print consistency, sharp deposit definition, and excellent release from fine apertures – all while lowering reflow temperatures to protect heat‑sensitive components. With its Type‑4 powder, ROL1 flux, and no‑clean residue, TS‑501 is the Type 4 solder paste that combines fine‑pitch capability with thermal protection and environmental compliance.
Type 4 Solder Paste – TENSAN TS-501 Mid-Temperature Solution
In modern SMT assembly, the choice of powder size directly impacts print resolution, transfer efficiency, and defect rates. Type 4 solder paste (with powder size 20–38 μm) has become the industry standard for fine‑pitch applications, offering the optimal balance between printability and soldering reliability. Whether you are printing 0.4 mm pitch QFPs, 0.25 mm ultra‑fine pads, or dense BGA arrays, selecting the right solder paste type 4 is critical for achieving high first‑pass yields.
TENSAN TS‑501 is a Type 4 Solder Paste engineered specifically for mid‑temperature, lead‑free SMT processes. Formulated with a Sn‑Ag1‑Bi35 alloy, this solder paste type 4 product delivers exceptional print consistency, sharp deposit definition, and excellent release from fine apertures – all while lowering reflow temperatures to protect heat‑sensitive components. With its Type‑4 powder, ROL1 flux, and no‑clean residue, TS‑501 is the Type 4 solder paste that combines fine‑pitch capability with thermal protection and environmental compliance.
What Is TENSAN TS‑501 Type 4 Solder Paste?
TS‑501 is a lead‑free, no‑clean Type 4 solder paste designed for SMT assembly processes that demand:
As a solder paste type 4 product, TS‑501 is trusted by manufacturers producing LED lighting, automotive electronics, consumer devices, and telecommunications equipment where fine‑pitch printing and low‑temperature processing are essential.
Key Specifications
Alloy Composition & Physical Properties
Chemical & Electrical Properties
Physical Properties
Test methods conform to IPC J‑STD‑004, IPC J‑STD‑005, JIS Z 3284, and Bellcore GR78‑CORE standards.
Why Choose TENSAN TS‑501 as Your Type 4 Solder Paste?
1. Optimised for Fine‑Pitch Printing
The Type‑4 powder size (20–38 μm) is specifically chosen to balance fine‑aperture filling with slump resistance. In a Type 4 solder paste, the particle size distribution ensures that at least 90% of particles are within this range, enabling reliable printing on apertures as small as 0.20 mm (8 mil) and pitches down to 0.25 mm (10 mil). This makes TS‑501 an ideal solder paste type 4 for high‑density boards with QFN, BGA, and 0.4 mm QFP components. The paste releases cleanly from the stencil walls, reducing smearing and ensuring consistent deposit volumes across the entire panel.
2. Lower Reflow Temperatures – Protects Heat‑Sensitive Components
Unlike standard SAC305 pastes, this Type 4 Solder Paste uses a Sn‑Ag1‑Bi35 alloy that lowers the peak reflow temperature to 210–230°C. This protects LEDs, plastic connectors, flexible substrates, and other thermal‑sensitive parts from degradation, while the fine powder ensures rapid melting and uniform wetting. The combination of Type‑4 powder and Bi35 alloy makes TS‑501 a unique solder paste type 4 product that addresses both printability and thermal constraints.
3. Excellent Print Stability – Long Stencil Life
The rheology of this solder paste type 4 is engineered to maintain consistent viscosity for over 8 hours on the stencil under normal shop‑floor conditions (22°C, 50% RH). This reduces cleaning frequency, minimises paste waste, and ensures that the first print and the thousandth print have identical deposit geometry – a critical factor for high‑volume production using Type 4 solder paste.
4. No‑Clean, Low‑Residue – Saves Process Steps
The flux system leaves a clear, dry, non‑conductive residue that does not interfere with ICT or functional testing. This eliminates post‑reflow cleaning, reducing chemical costs and cycle time – a significant advantage when running fine‑pitch boards where cleaning under low‑standoff components can be problematic.
5. High Electrical Reliability – Even Under Humidity
With SIR values exceeding 1.7×10⁹ Ω (IPC) and 6.4×10¹² Ω (Bellcore), and passing 500‑hour electromigration tests, this Type 4 Solder Paste ensures that the residue remains electrically safe over the product’s lifetime. This is essential for automotive and telecommunications applications where long‑term reliability is non‑negotiable.
Recommended Application Parameters for This Type 4 Solder Paste
Stencil Design Guidelines
Stencil Technologies: Electroformed and laser‑cut stencils with electro‑polishing provide optimal printing characteristics. For solder paste type 4, a stencil thickness of 100–125 μm is recommended to achieve the ideal aspect ratio for fine apertures.
Printing Conditions
Reflow Profile (Recommended)
The lower peak temperature of this Type 4 Solder Paste protects heat‑sensitive components while the fine powder ensures rapid coalescence and strong joints. Adjust profiles based on your specific reflow oven and board design.
Storage and Handling Guidelines for This Solder Paste Type 4
Important: Do not mix leftover paste with fresh paste in the same container. Always warm up this solder paste type 4 in its sealed container to prevent moisture condensation, which can cause spattering and voiding during reflow.
Alloy Composition Overview (SnAgBi – Type 4 Solder Paste)
Typical Applications for This Type 4 Solder Paste
TS‑501 is ideal for applications that require fine‑pitch printing and lower reflow temperatures:
As a versatile Type 4 Solder Paste, TS‑501 delivers consistent printing on these demanding applications.
Quality Assurance
Every batch of TENSAN TS‑501 is accompanied by a Certificate of Analysis confirming:
Our rigorous quality control ensures that every shipment of this solder paste type 4 meets the same high standards of printability and reliability.
Frequently Asked Questions
Q: What is the powder size of TS‑501?
A: TS‑501 uses Type 4 solder paste powder, with a particle size range of 20–38 μm. This is a standard solder paste type 4 classification per IPC standards.
Q: What pitch sizes can this Type 4 solder paste support?
A: TS‑501 reliably prints down to 0.25 mm (10 mil) pitch, making it ideal for fine‑pitch QFP, QFN, and BGA components. The Type‑4 powder ensures good aperture filling for these small openings.
Q: Is TS‑501 compatible with my current stencil design?
A: Yes, if you are already using a solder paste type 4, TS‑501 is a direct replacement. We recommend an aspect ratio (width/thickness) of at least 1.5 for optimal transfer.
Q: Does this Type 4 solder paste require nitrogen reflow?
A: No, it performs well in air. Nitrogen can further improve wetting on difficult finishes but is not required.
Q: What is the shelf life of this solder paste type 4 product?
A: Six months from production date when stored at 5–10°C.
Q: Can I mix leftover TS‑501 with fresh paste?
A: No. Do not mix leftover paste with new paste. Always use fresh paste from the jar after proper mixing in your solder paste mixer.
Conclusion
For manufacturers who demand fine‑pitch capability and low‑temperature processing, TENSAN TS‑501 is the definitive Type 4 Solder Paste solution. This solder paste type 4 product offers exceptional printability, stable viscosity, no‑clean convenience, and proven electrical reliability – all with a lower reflow temperature that protects sensitive components.
By choosing TS‑501, you select a Type 4 Solder Paste that:
Contact Information
TENSAN VIETNAM CO., LTD
TS10 Road, Tien Son Industrial Park, Bac Ninh Province, Vietnam
Tel: +84‑222‑650‑8818
Email: mark@sztensan.com
