Everwide newsletter No.478

Experiment § Solutions for Preventing Cracking in High-Hardness Lens Coatings

In high-hardness lens coating applications, coatings are required not only to maintain excellent optical transparency, but also to provide abrasion resistance, adhesion, and long-term stability. When only a single coating layer is applied, the high hardness of the material can easily lead to cracking or delamination during environmental reliability testing. To address this issue, a primer layer is first applied, followed by a hard coating (Hard Coating, H/C). According to actual application requirements, various evaluations are conducted, including adhesion testing in which samples are boiled in water at 80°C for 2 hours, dried at room temperature, and then subjected to a cross-cut test to achieve a 5B rating. Based on the EN166 testing standard, UV environmental testing is performed for 96 hours, and the △Tv value of transmittance and haze before and after testing must remain within 5%–10%. In the steel wool abrasion test, no visible scratches are allowed after 10 reciprocating cycles using #0000 steel wool under a 1 kg load. The Bayer abrasion test requires a Bayer ratio greater than 2.5. In addition, after storage in a 40°C oven for 14 days, the viscosity must not increase compared to the normal operating condition at room temperature (20–25°C). Through two years of continuous testing and formulation optimization, the bite-mark issue previously observed on the backside PC material of TAC substrates, which caused an increase in haze, has been successfully improved (Figures 1 and 2). Currently, the product has met customer requirements in water-boiling resistance, long-term stability, and anti-yellowing performance (Figure 3). Further improvements are still being made to enhance the Bayer value performance (Figure 4). If you are interested in this product, please feel free to contact us.                                                                                                  — Author: Mr. Tsan-Hsien Hong

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Activity § Seeds of Growth, Learning Together

Recently, training coordinators and departmental seed members participated in the external training course, “TTQS Framework and Case Study Analysis,” to strengthen their capabilities in training planning and execution. During the course, participants from various industries shared their training management experiences and exchanged practical insights on workplace challenges and solutions. One colleague shared the following feedback: “I used to think that organizing training simply meant preparing the venue, printing handouts, and sorting documents after the class. After listening to the instructor’s explanation, I realized those are only administrative tasks. The most important parts of training are actually the course design, follow-up, and outcomes. When the right methods and framework are applied, the effectiveness can vary greatly even with the same amount of time and resources.”

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Knowledge § What Types of Acrylic Adhesives Are There? (1)

Adhesives containing acrylic ester functional groups can generally be classified as acrylic adhesives. They can be broadly divided into two categories based on whether a chemical reaction occurs during use. The first category includes adhesives that do not undergo chemical reactions, which mainly consist of three types. One type is solvent-based adhesives, where polyacrylate polymers are dissolved in organic solvents. Another type is water-based adhesives, produced by emulsion polymerization of polyacrylates in water. For both types, the adhesive is applied to the substrate surface, and bonding is achieved after the solvent or water evaporates and the adhesive film solidifies. A third type is solvent-free polyacrylate adhesives with unique viscoelastic properties. These adhesives can bond to substrates with only slight applied pressure and are known as pressure-sensitive adhesives (PSAs). In all three cases, the acrylic adhesives are already in polymer form during application, and no additional chemical reaction occurs during the bonding process.

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Living § A Brief Free-and-Easy Trip to Hong Kong

At the end of 2025, I traveled with my family to Hong Kong for a four-day, three-night trip. The overall cost of living was relatively high, with meals around NTD 2,000, and dining spaces often small, sometimes requiring shared tables. However, service efficiency was high, and many restaurant owners were friendly and welcoming. Notable impressions included the beeping pedestrian crossing signals, fast-paced traffic with frequent horn sounds, and the use of traditional bamboo scaffolding in construction. We visited Hong Kong Disneyland during the Christmas season, which was filled with festive decorations. The nighttime parade, drone show, fireworks, and artificial snowfall were especially memorable. The Victoria Harbour night view was impressive, and the Avenue of Stars, Star Ferry, and Hong Kong Observation Wheel offered great city views and experiences. Overall, it is highly recommended during the Christmas season. If I visit again, I would like to experience the tram, Victoria Peak, and more local food and attractions.                                                                 — Author: Ms. Hsin-Chieh Lin