Experiment § The truth about the yellow card
Recently made UV moisture double curing adhesive. Customer asks: Do you have a yellow card for coating? competitors do! When I got a sample of the competitor, it was made into a film with a thickness of 100um, and it was directly burned with flame. Why can a completely non-flame-retardant resin coated on the PCB board take UL certification? The answer is simple: because the board is flame retardant. The 100um glue is burned out quickly, and the board itself cannot be burnt, so it can pass UL's flame retardant certification (Figure 3, 4). Figure 5 is the LOI experiment (Limiting oxygen index). Mix the oxygen/nitrogen in different ratios, pass around the test piece, and then ignite with flame. The test piece can only continue to burn in an environment with a higher oxygen ratio, which means that it is more difficult to be ignited. Figures 6 and 7 show an environment with 16% and 20% oxygen. The former will go out and the latter will continue to burn. Competitors will be ignited above 18%, which shows that they are not flame retardant. These experiments remind us that when meeting certification requirements, we can see what we really need, not just a certificate.
─ Author: Mr. Hui-Xu, Li
Activity § Warm December
"Educational Youth 3" This activity invites participating colleagues to read "Five Training Stories." Teacher Yu shared "The tip of the iceberg" and "listening to the sound of the volcano" are two units (Figure 1). Colleagues took turns on stage to tell a summary of the story, focusing on learning the experience of systematic thinking and in-depth conversations. German customers visited to understand the development and manufacturing process, and also praised the plastic materials (Figure 2). The Chengda Formula Racing team issued a certificate of appreciation, thanking Everwide for our professional assistance in the production of the car shell, as well as sharing the perseverance of Japan's competition (Figure 3, Biweekly No. 309). Friends visiting in the cold winter adds a little warmth to us.
Knowledge § Single liquid condensation type RTV 1
Room temperature hardening silicone rubber can be divided into two types: condensation type and addition molding. Condensation type silicone rubber relies on moisture to carry out the hardening reaction, most of which is single-liquid type, commonly known as RTV1. The reaction of this kind of resin is divided into two stages: firstly, the hydrolysis reaction with the moisture in the atmosphere releases a chemical substance to obtain a silanol functional group, and then undergoes a condensation reaction to solidify. RTV1 can be classified according to the chemical substances released: acidic (release acetic acid), neutral (release methanol, ethanol, acetone, oximes), basic (release amines). Although there are many types, the three most common types are deoxime, dealcohol and deacidification. Different types of RTV1 have slightly different properties, and the effects of released chemicals on parts and the environment must also be considered.
Living § The beginning of the hundred mountains
When everyone is sleeping at 2am, my first visited to Hehuan Mountain at night, the journey of seeing the scenery was begun. I felt both anticipated and frightened. Was it a pirate ship or a treasure ship? The temperature at the foot of the mountain was about 11 degrees that night. I put on cold-proof clothes, headlights and the instant rescue headscarf from Kai. The first peak is the North Peak of Hehuan. The sky full of twinkling stars. I walked into the humble mountain, stepped on the ground with broken stones and wooden stairs, with a bright smile, step by step and start 0.1Kto the commemorative hundred mountains of life. The steep stone slope along the way, and arrow bamboo made me dare not relax for a moment, as long as I did not pay attention, the arrow bamboo will stab my buttom, as if reminding me that the cliff is on the right .It reached 1.7K at about 4am, and the sun that was about to wake up gradually brightened the mountain road. It turned out that visiting Hehuan Mountain at night was not terrible. The tranquility of the mountain made me devote to the embrace of nature. There was no starlit sky, no hustle and bustle of the city, no mixed air. My first mountain was dedicated to Hehuan North Peak. The beautiful sunrise is a precious treasure from this journey, and it is really worth the experience.
─ Author: Mr. Cheng-Xian, Yo
