For three consecutive months, our production line has been running lighting mainboards using our JiajinYuan LFP-JJY5RQ-0307T4 halogen-free, lead-free high-temperature Solder Paste. After being taken out of the refrigerator, it reaches the working viscosity after standing for 2 hours. During squeegee printing, the solder paste does not string or collapse, and after continuous printing of 200 pieces, there is still no obvious clogging in the stencil openings. This forms a sharp contrast with a certain Japanese brand we used previously, which required pre-warming for 4 hours in advance and repeated stirring midway to maintain consistency.

At the communication module rework station, when LFP-JJY5RNTT-305 solder paste is used with a nitrogen reflow oven, the solder climb height on QFN chip terminals is stably above 0.18mm, and the solder joint wetting angle observed under a microscope is generally less than 30°. In contrast, a certain domestic competitor tested in the same batch showed slight oil-powder separation after 3 hours of pre-warming, leading to local insufficient solder starting from the 150th piece, requiring line stoppage for re-stirring and replenishment of Flux diluent.

This batch of JiajinYuan temperature-stable solder paste all uses T3/T4 grade spherical alloy powder, among which the 0307 alloy has a melting point of 221–227℃ and the 305 alloy has a melting point of 217℃. Combined with ROL0 grade halogen control (measured 100–200ppm) and rosin-based carrier, it ensures sufficient melting within the 240–255℃ soldering window while avoiding excessive oxidation. Especially during secondary reflow of double-sided mixed assembly boards, the void rate of BGA solder joints on the back side is consistently controlled at 7.3–7.9%, far better than the industry average of 12%.

During verification of LFP-JJY5RR-0307 zero-halogen REACH solder paste at an automotive electronics factory in Dongguan, it was found that in heat sink soldering for LED headlight modules, the viscosity change of this model within 6 hours after pre-warming was only ±800cP, while a Taiwanese product in the control group fluctuated by ±2100cP over the same period, directly causing the SPI detection solder paste volume pass rate to drop from 92.6% to 85.3%. After switching to our JiajinYuan product, not only did the pass rate recover to 94.1%, but water consumption in the cleaning process was also reduced by 17%, because its residue is transparent and the ionic contamination value is below 0.3μg/cm² NaCl equivalent.

In the laser jet valve dispensing verification, under an environment of 25℃ room temperature and 55%RH humidity, LFP-JJY5RLJ-305 required no preheating of the solder paste tank after startup, and direct dispensing for 2000 times produced no solder balls or stringing. After the same can of material was used continuously for 36 hours, the solder joint bridging rate sampled under a microscope was 0.017%, while a certain European low-temperature solder paste under the same conditions saw the bridging rate rise to 0.042% after 24 hours of use. The root cause is uneven precipitation of rosin resin during its pre-warming process, resulting in viscosity gradient imbalance.