Everwide newsletter No.456

Experiment § Solvent-free UV adhesive for optical materials

Materials such as TAC (Cellulose Acetate), PC (Polycarbonate), and PVA (Polyvinyl Alcohol) are widely used in multilayer optical lenses, including polarized lenses and high-end sunglasses (Figure 1). Due to their differing polarities, these materials present adhesion challenges that affect the stability and durability of interlayer bonding. To address this issue, we developed the GS821 series, a solvent-free UV-curable adhesive designed to meet the demanding requirements of optical lenses. The GS821 series features a special molecular structure that provides excellent interfacial wetting properties. Upon UV irradiation, it rapidly cures to form a dense and tough crosslinked layer between TAC, PC, and PVA, achieving strong adhesion and long-term weather resistance. This formulation contains no volatile organic solvents, complies with RoHS and environmental standards, and is suitable for cleanroom-level lens encapsulation and lamination processes. After curing, the GS821 adhesive layer exhibits high transparency and extremely low haze, with a light transmittance exceeding 90% and haze below 1%, ensuring that the optical quality of the lenses remains unaffected. We welcome interested parties to contact us for more information.

— Author: Ms. Fan, Shih-Yu

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Activity § Visit from Sun Yat-sen University

In Week 17 of the course “Case Studies on Polymer Materials in Industrial R&D Applications” offered by the Department of Materials and Optoelectronic Science at Sun Yat-sen University, an off-campus field trip was arranged to Everwide Chemical. During the visit, students applied the knowledge they had learned in class by observing real factory operations, including production processes, work environments, product development, training, and corporate culture. The activities included introductions to various instruments, such as TGA and DSC, as well as two short lectures that provided insights into the development of rocket ablation materials and applications of electrical potting adhesives. This field trip not only broadened students’ horizons but also helped them explore their interests. We look forward to future opportunities to meet again, share experiences, and grow together (Figures 1–4)!􀑁􀑂􀑃􀑄􃉕􃉖􃉗􃉘􃉙􃉚

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Knowledge § What is static fatigue?(1)

Under long-term loading conditions, internal defects and surface flaws within a material can develop into cracks. These cracks gradually grow over time and eventually cause the material to fracture. This phenomenon is known as static fatigue. The force required to cause fracture due to static fatigue is significantly lower than the force needed to cause immediate failure, such as the material’s tensile strength. The greater the applied stress during static fatigue, the shorter the time until fracture occurs. Similarly, higher temperatures accelerate the fracture process under static fatigue. Examples of static fatigue include construction materials bearing long-term loads and aircraft wings during flight. Static fatigue can occur continuously over the entire loading period or in stages, cumulatively contributing to the material’s fatigue damage.

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Living § Reflections on the R&D Meeting

On the last Wednesday of April and May, I had the opportunity to attend the “R&D meeting”, which offered a behind-the-scenes look at Everwide’s product development efforts. These meetings featured several speakers from the R&D department, who shared their firsthand project experiences in a lively and relatable way, using photos and simple data to illustrate their points. As a student, I found their storytelling style both engaging and easy to understand. The talks began by introducing the company’s core product lines and market strategies, giving us insight into how developers consider user habits, competitor offerings, and technical feasibility when designing new products. One story that stood out was about a failed prototype. The team initially developed what seemed to be a promising product that met all requirements on paper. However, after testing, they discovered it lacked long-term stability and couldn’t withstand real-world conditions. Rather than giving up, the team analyzed the test data, identified root causes, redesigned the formulation, and even changed materials. Eventually, they overcame the challenge and successfully brought the product to market. What resonated most was the message that R&D work is not just about technical skill—it’s about resilience, problem-solving, and cross-functional communication. The speakers emphasized the importance of listening to feedback, identifying actionable insights, and translating them into technical solutions with flexibility and teamwork. These meetings gave me a deeper appreciation for the real-world challenges of R&D and demonstrated to me the significant dedication and adaptability required in this role. As an intern, this experience broadened my perspective and sparked even greater curiosity and excitement about what lies ahead in my future career. ─Author: Mr. Cheng, Cheng-Yu