Everwide newsletter No.56

There are two kinds of PHILIPS lamps used in Everwide Chemical Laboratory: one is HOK series, the other is HPA series, HOK series you can call short-wave mercury lamps. However, the HPA series should not be called mercury lamps. The correct term is high-pressure complex gas discharge lamps. Because the metal halide added to the tube is different, the wavelength position is different.

HOK: 80/120, as pictured above.

Long-arc medium-pressure high-power mercury (mercury) radiators consisting of a double-ended quartz discharge tube filled with mercury.：254nm

A long arc medium pressure high energy mercury lamp consisting of a quartz tube with electrodes at both ends, filled with mercury. It emits UV-C 254nm wavelength, but the main peak is concentrated at 365nm. Due to the generation of ozone, it is necessary to pay attention to ventilation. Restart to give the light source a few minutes of cooling time, otherwise, the heat will be generated, and a fan cooling system must be added.

The lamp is added with a precise amount of mercury bromides (mercury bromide) to stabilize the instability of the high-voltage gas discharge process and prolong the service life.

HPA: 400S, as shown below.

Double-ended medium-pressure metal halide (metal halide) radiators with iron and cobalt additives: 300~400nm

It has a medium pressure UV lamp with electrodes on both sides containing metal halides (with iron and cobalt additives) and a small amount of mercury. Different metal halides are added to the tube, so the position of the wavelength is different. If Fe metal compound is added, there will be absorption at wavelengths of 365mm and 415mm. If the Ga metal compound is added, there is absorption at the wavelength of 415mm. No ozone is produced. Restart to give the light source a few minutes of cooling time, otherwise, the heat will be generated, and a fan cooling system must be added.

─Author: Ms. Miao-Ling, Lin R&D Engineer, Everwide Chemical

In response to the demand for thinner buttons, the button process technology has been changed from traditional PC injection to UV overmolding. All processes are formed on PET, PC, and TPU substrates, and the total thickness of the buttons is controlled within the ultra-thin range of 0.2~0.5mm.

In order to meet the needs of various types of UV mold transfer, Everwide Chemical has developed five types of UV mold transfer adhesives to meet the diverse needs of customer products.

1. The thickness of the turning mold is less than 0.05mm, the button design of low film thickness, hairline, or CD pattern, featuring high hardness and high wear resistance. Recommended formula: FP8108H76, FP899, FP8993, FP8994.

2. The thickness of the turning mold is 0.2mm~0.5mm, the thickness of the middle film, and the requirements of high pencil hardness and low shrinkage are at the same time. Recommended formula: FP8893, FP8894, FP9542, FP9543.

3. The thickness of the turning mold is 0.5mm~1.0mm, the film thickness is high, and the pressing needs to have a PU resilient pressure touch and low shrinkage. Recommended formula: FP919, FP9514, FP9518, FP9254, FP9621.

4. The keys need to be solvent-resistant (isopropyl alcohol, IPA, and alcohol) and wear-resistant. Recommended formula: FP6111, FP6116, FK028, FK0285.

For related product information, please visit the official website of Everwide Chemical: http://www.everwide.com.tw/manuals/dm/UV-adhesive-for-Forming.pdf

Q1: What is the effect of UV glue when the irradiation intensity increases?

Too strong illumination has a negative effect on the properties of UV glue for acrylic systems. For example, increasing the illumination by n times can increase the initial reaction rate by n times, generate n times more radicals, and increase the growth rate by n times, but at the same time, the speed of the termination reaction will be increased by n*n times. In other words, too strong illumination will reduce the molecular weight of the adhesive and increase the number of chain ends of the molecular chain, instead of obtaining the optimal strength. Q2: What is the effect of UV glue when the irradiation energy increases?

Generally speaking, the UV glue of the acrylic system prefers to irradiate too much energy and avoid insufficient irradiated energy. Regardless of theory or practice, this type of UV glue has no obvious negative effects even if the irradiation energy exceeds 10 times the original recommended value. It is speculated that the irradiation energy maybe hundreds of times higher than the original recommended value, and there will be obvious concerns about the photoaging reaction.

I remember when I was in elementary school, my father would sometimes bring a lunch box home after getting off work. It may contain bread, cakes, and drinks. At that time, I only thought that my father was working well and could eat such delicious food. Now Yongkuan holds a new product launch conference every month, and I can also eat lunch boxes every month, but only then did I understand that eating lunch boxes is very hard, because there is no time for a good meal, so the lunch boxes are replaced. If you eat too much, you will worry about getting sleepy at the meeting, so you have to go hungry. No wonder Dad didn't finish the lunch box, so I picked it up cheap. Colleagues of Everwide, please feel the boss's mood more when eating the lunch box, and take the meeting to heart. As for the unfinished meal box, take it home to the child, he will definitely feel great.

─Author: Dr. Ye-Xu Li, Everwide Chemical

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