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Everwide Newsletter No.130

Experiment § The future development of encapsulating LED?

At present, the materials used to encapsulate LEDs are based on two-component epoxy resin, the A agent is based on resin, and the B agent is based on MEHHPA. The full name of MEHHPA is Hexahydromethylphathalic anhydride and the number is CAS No.25550-51-0. Some industrial-grade raw materials contain different proportions of isomers, and some raw materials are mixed with HHPA (hexahydrophthalic anhydride, 85-42-7). On September 3, 2012, the European Chemical Agency (ECHA) listed MEHHPA and HHPA as the candidate list of Substances of Very High Concern (SVHC). This is really a century-level event in the LED packaging industry. Please see item 10 of the reference data:

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This is about raw material factories, packaging factories, LED application customers, etc. How should we treat this matter? Is there an alternative plan to substitute raw materials? We welcome everyone to join the discussion, maybe brainstorming will bring new gains! Discussion area:

─Author: Dr. Ming-Xu, Li


Activity § Education and training of the manufacturing department: Cafe talks

The book shows that people like to communicate and are willing to put forward their own opinions. In order to test this idea, we divided the training time of the manufacturing department into three weeks and let colleagues try Caf 'e-communication mode. Different from the general lecture-style teaching, we divided it into three processes of "focus on consensus", " Communication and Conversation " and "share harvest", and adopted the group mode to carry out the teaching. One week before the event, we first select the host of each group, rehearse the process once and explain the principles of the event. The first process is "Focus on Consensus": We broadcast videos of the working conditions of world-renowned companies for colleagues to watch so that everyone can compare their own current situation and generate "consensus". Then the host of the event used two topics about "Focus" as materials to be brought into the " Communication and Conversation " next week. The two topics are: What do you see in the film? What are we missing? "Communication and Conversation" is the center of the whole event, and everyone contributes their opinions from various angles. Under the guidance of the host of each group, we heard applause, laughter, and communication from the group from time to time. Finally, everyone recorded the results on the wall newspaper and waited for it to be published next week. The last process is "sharing the harvest". Everyone can present the results freely, and each group will share in their own way. Unexpectedly, everyone entered into a wonderful and lively debate again, and laughter and applause continued. The whole event was successfully concluded with the encouraging conclusion of the seniors. We would like to thank the hosts for their assistance and the wholehearted participation of all colleagues in the department. The communication mode made me feel that my colleagues are very thoughtful, as long as they have the opportunity, they are not hesitating to contribute and are willing to participate. This activity is just the beginning and we will use this theme to continue the activity and let our colleagues formulate improvement projects, which will surely continue to improve the quality of our work.

——Author: Mrs. Er-Kai, Ye


Knowledge § Can epoxy resin and light-curable resin react completely?

There is almost no such thing as a "complete reaction" in thermosetting resins, only the question of the conversion rate. Epoxy resin is a typical example. The collision reaction of two functional groups (resin and curing agent) needs to break through the activation energy of the reaction, especially after the resin is gelled, the functional groups can only collide together by diffusion movement. As the reaction rate increases, the concentration of functional groups will gradually decrease, the Tg of the relative resin will gradually increase, and the energy required for diffusion movement will also increase at the same time. In the end, the activation energy of further reactions may be higher than the activation energy of some structural cleavage, making it impossible for the epoxy resin to reach the state of complete reaction and the light-curable resin will not completely react. According to the number of acrylic functional groups, the reaction rate of the light-curable resin is about 80~90%, so there will be functional groups remaining. The reaction rate of the multifunctional monomer is lower than that of the monofunctional monomer, so the residual amount of the functional group is larger. From the point of view of the initiator, the reaction will only consume 20-30%, and the rest will remain in the cured product.


Living § Greet enthusiastically

Carnegie has a happiness equation: the more you smile, the more body language you have, the happier you will feel. The most practical application that many colleagues have suggested in class is that we should greet each other with more enthusiasm. Regarding greeting, my enlightenment teacher is the uncle. One day about 15 years ago, my uncle and I visited a customer at Shihlin Electric company in Hsinchu city. We walked in the vast factory area, there are many factories here and when the uncle saw people, he raised his right hand and waved to say hello: "How are old friends?" If we are far away from other people, my uncle will also say hello. This one is the staff who develops and designs the transformers, that one is the monitor who fills the resin on-site, and there is a purchaser. My uncle introduced them to me one by one. We visited several departments, and I suddenly felt that the uncle has an indescribable superpower, because almost every employee recognizes it. I don't think even the boss of Shihlin Electric company can do it. Just as the uncle greeted others in a loud voice, calling them "old friends", I noticed that several people's expressions were first taken aback, and then they nodded with smiles on their faces. I took an opportunity to ask my uncle: "Do you know the person who just greeted you?" Uncle said, "I don't know, it seems to be an operator in the winding area." I was surprised to hear it! I said, "You don't know people, why do you call them "old friends"?" My uncle replied playfully, "As long as we say hello, we know each other." At that time, I thought it was funny because my uncle defined a friend as very interesting. But now in retrospect, the uncle is really a great business wizard. But now in retrospect, the uncle is really a great business wizard. In any case, in the end, they will feel that seeing the uncle is like seeing a happy old friend. No wonder the uncle lives very comfortably in the huge Shilin Electric Company.

─Author: Dr. Ming-Xu, Li


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