Everwide newsletter No.469

Experiment § AT-710 Automatic Potentiometric Titrator

Red adhesive (chip red adhesive) is a material used in electronic assembly processes to secure components, ensuring they remain safe through subsequent high-temperature and vibration processes. In the Surface Mount Technology (SMT) process, small components such as resistors and capacitors often have a small dollop of red adhesive underneath (Figures 1 and 2). Its function is to form a central “adhesive bump” under the component before reflow, preventing the component from shifting or falling off due to vibration, airflow, or high temperature. The red color is intended to allow equipment and operators to clearly identify the adhesive location, improving process inspection efficiency. The true test of red adhesive performance occurs before heat curing. The adhesive bump must remain pointed and not collapse, and the dispensed volume must be precisely controlled. Too much overflow can affect component leads, while too little cannot secure the component effectively. Even during long waiting periods or production line stops, the bump height must remain stable to prevent inconsistent component heights that could affect soldering quality. This is especially critical for high-Ti components (tall leads, thin leads). Red adhesive is a mature and stable material. Everwide offers a variety of products, including JC711-6, JC711-27, JC812-2, and JD459-3 (for PLCC), which can be selected according to viscosity, curing conditions, and component type (Figure 3).                                                                                        — Author: Ms. Ming-Hsiu Lai

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Activity § R&D Colleagues Invited to Give a Talk at YunTech

R&D colleagues were invited to Yunlin University of Science and Technology to share with first-year students their experiences on career planning and preparation from the perspective of industry practitioners. Two key suggestions were offered. First, become proficient in your own field and learn by working backward from the final product. Understanding where and how a product will ultimately be used, and then revisiting the materials, formulations, and processes involved, provides clearer direction and makes learning easier to retain. Second, think early about which path you would like to pursue and begin preparing as soon as possible. Start with product categories that interest you, such as cosmetics, advanced materials, or 3C devices. Once a direction is identified, actively accumulate relevant knowledge. Over time, you will find that you have already progressed a long way. There is no standard answer when it comes to career choices. What matters is exploring early and accumulating continuously. Every decision and effort contributes to building the path ahead, and time will eventually reward your commitment and persistence. In fact, this applies not only to chemistry, but to life as well. Many efforts that show no immediate results often lead to unexpected outcomes in the end.

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Knowledge § Where is the swelling ratio used?

The swelling ratio is a measure of the volumetric change of a material after being immersed in a solvent and reaching equilibrium between the material and the solvent. It is commonly used in the rubber industry. Many rubber applications involve contact with solvents, and the volume change is much more important than the weight change; therefore, swelling ratio experiments are conducted. By immersing rubber in different solvents, a larger swelling ratio indicates that the solubility parameters of the rubber and the solvent are closer. This relationship can also be used to estimate the solubility parameter of the rubber. For rubber of the same material, a higher crosslink density results in a lower swelling ratio, which can likewise be used to estimate the crosslink density or the reaction rate. Swelling ratio experiments are suitable for rubber (or rubbery materials), but not suitable for glassy thermosetting resins. On the one hand, the time required for these materials to reach equilibrium with the solvent is very long, making it difficult to determine the equilibrium time. On the other hand, solvent absorption and the resulting volumetric expansion generate significant stress, causing the specimens to crack or break; thus, the experiment cannot achieve its original purpose.

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Living § Hobbies often spring from daily life

After the pandemic, I finally joined the long-awaited employee trip. The first stop was Mt. Sarakura, famous for its “hundred-billion-dollar night view” overlooking the coastal industrial landscape. Along the way, I noticed that elderly Japanese remain active in the workforce, prompting reflections on career opportunities for senior workers in Taiwan. We then visited Mojiko Port, where restored historic buildings evoked the Taishō and Shōwa eras. On the second day, we enjoyed the tranquil scenery of Lake Kinrin in Yufuin and the colorful hot springs of Beppu’s Umi Jigoku. The third day included feeding lions on the Jungle Bus at Kyushu Natural Zoological Park and taking in the 360-degree view from Daikanbō in Aso, a humbling experience. We also toured the tenshukaku of Kumamoto Castle, learning about its history, architecture, and post-earthquake restoration, with impressively preserved records. Finally, at Dazaifu Tenmangū, we learned the shrine etiquette of “two bows, two claps, and one bow,” concluding this journey through Kyushu’s nature, history, and culture.

— Author: Mr. Chia-Jung Tsai