This article is a continuation from the last time.
“Glass wool” is used as a sound absorbing material all over the world, except for urethane. As the name suggests, glass wool is a product that processed glass material into a fibrous form. Therefore, it is resistant to heat, so it can be used as a variety of building materials. In the case of glass wool, the sound absorption effect will change depending on the specific gravity. The sound absorbing effect in the low range can be obtained by having the specific gravity as much as possible.
However, there is only one drawback. Because it is made of glass material, it becomes prickly and itchy when used in bare indoor. People sensitive to the skin may be afraid of sleeping at night. It is good to roll it in cloth when using it. Also, please cut off ventilation and mask as it scatters when cutting.
This is a material is called “Rock wool”, it is similar to glass wool. A wider range sound absorption effect than glass wool can be obtained. Focusing on the specific gravity, measures can be taken at lower frequencies. However, please note that as it scatters like glass wool, the skin may get itchy. In addition, the price is higher than glass wool. Although it may be mistaken often for asbestos, please be relieved as it is a different one.
Recently “Polyester wool” has been drawing attention. It is ecological as it makes fibrous crushed materials such as plastic bottles. Besides, there is no tingling sensation like the above material. It is used for clothes and futon cotton as it is familiar. You can use it even while it is exposed, and the price is reasonable, so it’s easy to use. However, compared to the above needs, it is thin as its use as a building material, so there is not much adjustment of specific gravity.